Another good point I forgot to mention is heat scavenging and Tesla octovalve. Heat loss in motor(s), battery, inverter and other electronics inside the car can be captured and used for heating up battery or cabin. This also applies to 800 V cars if they have implemented it. This means that the slightly increased heat loss in 400 V systems can be used for something useful rather than just dumped outside. But this also means that the heat loss generated in 400 V - 800 V conversion in Taycan/Ioniq/EV6 can also be used for heating up other components in the car. It boils down to how well car manufacturers can utilize the heat. My claim is that Tesla with their octovalve is the best when it comes to exactly that. A well-designed 400 V car can be more efficient than a badly designed 800 V car.
I'm glad that GM implemented this heat scavenging in their Ultium platform. Are you going to review a Cadillac Lyriq? Maybe one made in China? Thanks for your work !
In Electrical Engineering, 400V and 800V are both low voltages, the insulation, power electronics etc are not goona ba that much different. The difference between 400A and 800A (respective current need for 300+kw charging) is gonna be much more significant in terms of electrical system design. Heat loss is squared, but you don't need four times more insulation for double the voltage.
@@dragospahontu they should just have cheaper 400v 3 phase 11/22kw chargers.. if your car needs quick charging while you are at the cinema you've driven way too far to watch a movie :)
bjorn, as an old, retired, automotive engineer i agree with your point of view 100%. one principal of engineering that i didn't hear you mention was the law of diminishing returns. so any voltage can be used to power an ev. from 3.7 up to 10,000 volts. if you plot the efficiency versus system manufacturing cost, my guess, and i must stress this my guess, is that there would be a local minimum around 400-500 volts, where the manufacturing costs for an 800 volt system is higher than that of a 400 volt system.
Hey Bjørn, Very interesting thoughts - thanks for the video! Perhaps some counter arguments in favour of 800V, if I may; 1) Cost. We see evidence that 800V architecture is actually already cheaper than 400V platforms... e.g. on Tesla's prior earnings call Elon and Drew said switching to 800V for Model3 and ModelY would save about ~$100 per vehicle. However, at the moment their volumes do not make sense to switch considering all the sunk cost in 400V components and supply chain. Basically it would cost too much to change over at this time... but if they were starting a new platform, its obvious 800V would be the choice. That said, its pretty clear Cybertruck and Semi will be 800V, so I think we'll see R&D costs of 800V tech trickle down and be applied. For example, if Tesla ever get to 2M vehicle production PA, $100 x 2M vehicles = $200M savings per year which is not insignificant Another good indication of lower cost is the BYD eMotion3.0 platform going 800V for mass market vehicles. Even their new compact BYD Dolphin which has max charge rate of 60kW is based on this 800V platform rather than their 400V platform. Pretty solid evidence this decision is based solely on cost (most important factor in China), and not charging speed (60kW is obviously easy to do on 400V)... and this cost saving includes the 400V-800V translation / backwards compatibility. 2) Technology. You highlighted in the video Hyundai/Kia's method of using the traction inverter electronics to do the 400V-800V translation. This revolutionary technology means the cost of backwards compatibility is basically $0 (everything you need is already included in the powertrain) A few in the industry started calling this the Onboard DC charger (OBDC), and in my opinion, it is revolutionary. I see pretty much every 800V platform moving in this direction (e.g. Hyundai, Kia, BYD , XPENG, Volvo, etc and probably even Porsche/Audi on their refresh PPE). So not only is the OBDC cheaper (its free), it allows much fast charging over voltage doubling method like Taycan... for example, you note in your testing that Taycan only gets like ~38kW on a 50kW charger, whereas IONIQ5 with OBDC gets a constant 50kW... e.g. 30% faster charging. This is because the IONIQ5 can request max voltage and therefore max power, and does the charging onboard. The same applies to 400V EVs without this OBDC... e.g. a Model 3 capable of 250kW charging also charges
Korean 800v kicks ass for the lord on slow(50-100kW) chargers here in Poland, where other cars are limited by amperage, Koreans gets full charger speed...
You are correct, we are still mostly limited by the individual cell C rate, and its heat rejection efficacy. Doesn't make a lot sense to go to higher voltages until that is improved. You gain a % or two through lower amperage in charging and powertrain circuitry, but not a ton as you said. There's no real downside though other than making sure components are rated as such, so if they want to be on 800v platform, might as well. However, huge battery packs well over 100kWh will benefit from higher system voltage due to the sheer number of cells.
All cars could have an “eco-charge” option. Even Tesla you are degrading battery with much supercharging. If you know your going to stay a place for 45 minutes, why fry the battery when it’s not necessary.
Tesla wants you to charge fast and make room for newcomers. If so many people went for a 1h dinner all stalls would be taken for too long when using eco mode.
@@bjornnyland Bjorn, maybe you know. Is the build-in charger more effective at 12kw or at 5kw? In the beginning i was charging my model 3 at 5kw at home but then realized that a computer power supply with a gold rating only achieves this at 80% load, then the load is much lower, the computer PSU becomes far less efficient. I then assumed this is also true for the build-in charger? (especially in the winter as a bit more heat in the battery might make the charging more efficient as well? Many thanks for your thoughts!
Ah fast charging at a slow rate? You don't need 800V tech for that. Also people waiting will not be happy for eco mode charging. Just use a 50KW charger, that is gentle to your battery. In a Tesla S/X: 125A : 74 cells is just 1.7A per cell which is below 1C.
Well, my real world experience in Germany and Austria after 25.000 km in an Audi e-tron GT ist that in ideal cases (IONITY oder FASTNET) I average 177kw charging between 5-85% so my fast charge takes 15-20 min. I drove the BMW i4 M50 for 1.500 km that sucks completely. The 10-80% took the BMW 45-60 min. and after a short peak at 170kw it drops quickly to 50-60kw and stays there all the way till 80% averaging way below 100kw! The Mercedes EQE 43 I drove for approx. 1.200 km is better than the BMW but still worse than the Audi as it kept the 160-170kw peak longer and averages slightly above 100kw. Nevertheless it also took the car 30-35 min to charge from 10-80%. On long trips if you charge 1-3 times that makes a huge difference!
For cars with battery packs under 100 kwh, it doesn't make sense to switch to 800v. If the system is initially designed there, fine, but for Tesla, makes no sense to switch their cars over. For vehicles with much larger packs >100kwh, 800v will be helpful as you need a lot more watts to charge in the same timeframe. For large trucks, semi's, etc. 800v or more makes sense. For small cars like the Model Y and 3, it makes no sense to switch.
But 400v is smaller, lighter and requires less power management than 800v. So it makes even for semis and trucks sense to use 400-450v. Adding to that you cant get the full power on a 400v charger with a 800v car. And there are more 400v cars because they are cheaper to make and because of that the mass of cars.
@@gforcefabi Like Bjørn explains in the video, what is in a 400/800 pack does not change given they are same capacity, only how stuff is internally connected. If going by 4V/cell, you'd need 200 in series to make a 800V pack of say 60kWh. 100 cells in series would make a 400V pack, but then you'd only have 30kWh of capacity, so you'd need to add another 100 in parallel to make capacity equal. At the end of the day, either 60kWh pack would still have the same 200 cells, and therefore weigh the same, and need the same degree of battery management.
The main advantage at 800 V is that you can get the same power as 400 V using cables with smaller diameter. The diameter of cable is determined by current, therefore you can use less material in the system. The charging stations could deliver much power without using liquid cooling in cables.
Not just the cables. 800V allow for thinner coiling wires in the stator of the Taycan’s motor that save weight. Then you can go and put more luxury and safety features in the car.
@@JamesWindland it's probably negligible... in the battery pack you probably have to use the same amount and in the rest of the veichle i don't think it would be that costly... remember... you have to have stronger ICs on 800V... 800V would be great in heavy veichles like cybertruck, hummer ev and f150 and by the time it will be in 99% of chargers it should be in every car but that time is not today, like bjørn said
My guess would be that the Korean cars do it by running the inverter and rectifier (normally for regen) at the same time. The inverter side takes in the 400VDC, turns it into AC (possibly both share the task of upping the voltage, so it sends out say 550VAC), but instead of driving the motor, sends it straight to the rectifier/regen side to be converted into 700VDC. If this is the case, it would be less efficient than the Taycan's DC-DC conversion, but less physically wasteful as it is using hardware that is already in the car anyways, rather than adding an extra part.
Using a "pure" inverter you cannot step up the voltage - you'd need to add a transformer for that (well, I guess technically there are other ways, but AFAIK a small transformer is the most efficient way).
Watching the beautiful Norwegian scenery go by while listening to Bjørn's thoughtful commentary was a real treat. I do agree with Bjørn's conclusions and happily drive my 400 V Teslas while looking forward to an 800-900 V future, thanks to forward thinking engineers at Porsche, Lucid, and Hyundai.
As a car manufacturer expecting to adopt 800 volts in the future, I can just start with 800 anyways to gather experience. Porsche is not a company which sticks with old stuff because it is cheaper. It tries to provide customers with the best tech available.
Not really. According to information received by Tesla enthusiast Sawyer Merritt, the automaker plans to increase V3 Supercharging speeds to 324kW in the third quarter of this year. With a 400V system.
My EV6 holds flat 170kw up to 80%, and peaks at 241kw. I thought this was mostly because it has 800v so it has less overheating and can push harder. But now I am confused. If the batteries are all 3.7v, which makes sense, then why are the egmp cars like EV6 and Ioniq 5 so much faster at charging than all the non-tesla and even faster at a higher SOC than the Tesla cars? I don't know. I looked up it up and the Electrify America chargers in the US charge at up to 350A at 1000v, so maybe that is why my experience is good with the 800v cars in the USA.
Very simple, the answer lies in 2 aspects: thermal management, and low internal resistance. The eGMP cells have a low resistance and are the first pouch cells to be directly in contact by the bottom to the gap filler and cooling plate.
If they don't have a superior heating/cooling and battery chemistry systems and the manufacturers are pushing higher charging speed, expect less battery life, than manufacturers that are charging at lower rates. People are focused too much on charging speed, manufacturers aim to please, but it's generally at the cost of the battery life. As end users we will only find out 3-7 years down the line. I charge at the lowest possible rate I can live with. (I have no choice when using high speed chargers - but avoid them as much as I can)
Good points. Since most 400 volt stations really peak around 480-500v, I too am in favor of 450-500v battery pack for personal vehicles and save 800v for larger vehicles like trucks and buses.
@@MacGuyver85 That depends on the design of the pack and the charging infrastructure. The porsche solution is expensive, heavy and inefficient. But it's also pretty damn old by now. Kia/Hyundai does it better and future cars won't need a transformer at all.
@@mho0 The porsche solution IS expensive. But it's really old by now. The goal is to get rid of active components like converters. In general, component cost is the major factor to be considered. Everything you can solve with more simple components will be done the cheaper way even if software development costs skyrocket, simply because development cost is a one time investment, while manufacturing costs scale with volume.
I disagree. The current CCS spec (Edition 4 ,NOT Version 2, IEC 62196-1:2022) goes up to 800A and 1500V. But with so many amps you need cooling. With 800V charging up to 200kW without cooling could be possible. HPCs that don't support >500V are very rare. Generally chargers are more amperage limited thant voltage limited. For that reason alone 800V makes sense.
Completely agree, the cost difference between a 120kW charger with a 200A cable vs a higher current (water cooled jacket etc.) cable is significant. Hence so many 120kW chargers fail to deliver above 80kW on 400V cars. 800V cars don't suffer from this problem at all.
The units (in north America) we call 340 kW dcfast are rated at 1000 volts to supply 340 amps. So a 740 volt (voltage depending on state of charge) battery could take up to 250 kW. There are 500 amp units out there too. Not cheap to build and provsion I'm sure. Back in the fall of 2019 in Canada the Kia Rep said they were building 800 volt architecture in their future designs. They did.. Beats the crap out of a 40 kW to up to max 74 kW Niro EV charge rate.
According to information received by Tesla enthusiast Sawyer Merritt, the automaker (Tesla) plans to increase V3 Supercharging speeds to 324kW in the third quarter of this year. On a 400V system.
Great video Bjorn. I think it's like the age-old question - "Which came first, the Chicken or the Egg?" - Same with 800V. Either the cars move there 1st and the infrastructure catches up or we wait for infrastructure and the the cars catch-up. Here is the US, we have issues with the (non-Tesla) charging network - a lot of 50kW chargers, not enough chargers, out-of-order chargers, etc. so the wait for the infrastructure may be longer than in Europe. Thanks for sharing your insight.
I pointed out in this video that the 800 V chargers are backwards compatible with 400 V cars. This means that we can start rolling out 800 V chargers and still make 400 V cars until the battery packs are large enough to where 800 V makes more sense.
@@bjornnyland Agreed... just saying the opposite is also true - as is being done. Make 800V vehicles that can charge off the 400V infrastructure until the Infrastructure catches up. Not arguing, just stating both concepts have some merit.
But adding 800 V chargers doesn't give any disadvantage to 400 V cars charging on them. But making 800 V cars that needs to charge on 400 V chargers is a disadvantage.
One more advantage with 800V is the charger limitation to 500A (not with SuC of course, but all the others). Taycan would be unable to charge with >200kW on a 500A-limited charger.
Reminds me of the discussion of household voltage. 220VDC became European standard after WWII since the overall system had been destroyed and needed to be rebuilt. The US stuck with 110/120VDC, even though the physics suggested higher voltage would be better. A similar argument would have had Europe adopt 60 hz, but it was too late to shift from 50hz. Standardization sometimes does not end on the best tech.
@@GameOver556 Almost all houses in the US have 240 V already (it's a nominal 240 & 120 here not 220 & 110 like most people say) but it just isn't used for most common outlets. 240 V is only used for high power devices like electric ovens, electric central AC/heat, clothes dryer, and hot water heater. I don't think common household appliance usage will ever switch to 240 V. Yes, nearly all devices today can accept 240 V with universal switching power supplies but there is no compelling reason to change.
@@GameOver556 Sorry for the late reply. 15 amp 120 V installs in the US use 14 AWG wire, which is 2.5 mm2. 20 amp 120 V installs use 12 AWG (4 mm2) or 10 AWG (6 mm2).
On a side point (at 16:30) all DC - DC converters consist of an inverter followed by a transformer rectifier. If it is regulated then the regulation can be done at the inverter or by a buck regulator following the rectifier.
DC-DC converters does NOT need to have an whole inverter and transformer. Buck (also boost) regulator is a type of a DC-DC converter. You do propose chaining 2 DC-DC converters first one - isolated non regulated, second one non isolated regulated buck converter. That is atrocious, why even use isolated converter (with a transformer) and why 2 stages (roughfly 2x power dissipation)???
I think EVs need to be future ready because they have the potential to last a looong time. If I buy a car in 2024, I would prefer 800V. I have designed RC cars for inter college competitions and I know how easy many things are if you have a higher voltage system.
@@bjornnyland agree with everything but your comment about 400V chargers, why scrap all the existing 400V infrastructure when you acknowledge that Hyundai/Kia E-GMP platform has cost effectively resolved DC-DC conversion (unlikely Porsche)? Apparently Cybertruck will be 900V, it will have #OBDC to leverage existing Superchargers. With onboard DC charger V4 Superchargers can be simplified.
Great conclusions. Min 22. make cars more efficient (less weight, better aerodynamic, less battery, etc), not a bigger battery. (Follow the glider principles, not the Hummer way).
Your arguments are all correct. But you need also to see it from the perspective of the charger companies. Why should they build 800V chargers if there are no 800V cars? If you want to ultimately switch to 800V someone needs to provide demand for it and the trucks are not really providing much demand for manufacturers to switch to 800V. It's the old chicken-egg-problem. Someone needs to start to base everything on 800V systems, otherwise they will not ultimately switch to 800V architecture.
You are presuming that 800V chargers are better, when they are not. By your presumption, then 1600V would be even better. The hope is that future battery chemistry will be smaller packs, with higher energy density, not bigger battery packs, that require higher voltage.
You are right. With current battery tech, 800V is not that useful for cars. The only benefit now is with the lower current, you can get away with thinner high current cables used in the car. For trucks, bus and ferries however, you probably want 800V or even 1,000V because their huge battery pack can handle the extra energy and there is a limit on how thick a cable can practically be in term of the volume occupied in the vehicle, of cost (thick cables are very expensive) and the fact that the fast charger cable needs to be thin enough so it can be plugged and unplugged using human hands even at -35°C. Ideally future fast chargers should have a DC to DC converter providing the voltage needed by a charging vehicle instead of a fixed voltage. From what I heard, the Tesla Semi will questionably use two 400V battery packs instead of a 800V one. To charge you will have to use two plugs from two different chargers on top of each other.
But the installations cost enough that its probably best to future proof them a bit before the cars arrive that can use them. Then the old chargers must be upgraded in the future. But as one of your American viewers I appreciate your explaining this since our schools don't teach anything that is actually useful in the real world.
Without watching the entire video I think you need to take a look at how the power delivery is. With higher voltage you get more W.h through one cable of a specific diameter. It's not about loss, its about saving copper, weight, lowering cost and needing less infrastructure.
@@bjornnyland And yet you kept talking about resistance and heat. I did watch 90% and while you touched the subject I believe the reason is cost. It's all about the money, always is. And since this is the Internet and the vocal delivery benefits are lost, I want you to know that I am not trolling and all is cool as a cucumber.
I think it makes sense to develop new platforms with 800v architecture. If it is as you say, that 800v will make sense in five years, the E-GMP platform is probably more future proof than MEB even if there is no to little advantage for the cars produced today
It’s not all about charging. 800V makes sense for performance. If you pull Less amps from the battery to achieve the same power, it will take longer to overheat. This is why Taycan can launch consistently for longer.
Then what about the Tesla Plaid with 400v? It's just about engineering. Porsche, Audi, Lucid etc just found a easier way out with 800v, might be because of lack of engineering. Now 4680 cells will roll out with 400v and it will be able to charge with +370kW. Of course 800v is better for performance and charging but not for the time/tech we got in today's cars, tesla shows it isn't necessary with a 800v yet.
Incorrect. Model 3 Performance can also launch consistently for longer. Porsche (intentionally?) compared Taycan against older Model S tech. But compared against more modern Model 3 tech, then the Porsche had no real advantage. ruclips.net/video/YVaebcsHNFU/видео.html
Say you have a 100kW charge/discharge on a battery pack. One is 370V 200 cells, 2p100s. Other is 200 cells 1p200s at 740V. For battery pack 1 this means 270amps at 100kw, for battery pack 2 this is 135amps. Now for the cells, in both battery packs, the internal resistances are the same. (At 0,001ohm per cell, total of 200 cells is 0,2 ohms for the 1p200s, and 2x 0,1 in paralell is 0,05 ohms for the 2p100s. at 100kW this means 270x270x0,05= 3.6Kilowatts of loss for the 340V pack. (P=I2xR) and for 135x135x0,2= 3.6kilowatts of continious loss for the 740V pack. (Obviously cell internal resistance for this example is exaturated) so far we have no additional gains. The cells in series, the resistance you can just add up, in parallel you cannot. (In my example, just 2 parallel of the same value is the same, so in reality it becomes more complex), but losses increase a lot with current, magnified by additional heat in the cells and copper. More cells in series, means more voltage, which translates to less current per cell, which is less losses per cell. You can reverse this by saying that both battery pack needs to deliver 135amps for each series, so the 1p200s 740v pack delivers 135amps, with 200 cells, and the 2p100s delivers 135 amps per parallel string with 100 series each. 740V is 0,67 amps per cell, 340V is 1,35amps per cell. Just comparing Tycan and Model3 is kind of a short cornering, because of different battery capacity, the Tycan has 30%-ish more capacity. So for the same voltage, it has more in paralell. So the total internal resistance of the pack is always higher as your capacity increases.
Agreed 100%. 800 volt will become more important with larger packs >150 kWh that can charge at >300 kW. In those situations, it will be important to keep the amps down in the charging equipment. But for the cars we have today, 800 volts has no practical advantage.
Agree efficiency ionic classic 28 was my best, model 3 SR+ and now have a tesla model s 75- today i did nearly 1000km in UK and was achieving 240wh/mile- lowest was 180wh/mile pretty good for a 5 year old Tesla. they are still more efficient than lots of newer ev's. The new ionic 5 has gone backwards with efficiency- thats why love mini electric and new model 3 LFP.
Great thoughts on that topic. Sure a 3ph inverter can be used as a DC DC converter, but what out, looking at peak power of the rear drive unit does not mean that it is a power that can be maintained for a consistent charging session. Like this podcast format !
If we boil it all down, the only thing 800V does is fiddle with the balance between conductor thickness and (very small) resistive losses. It isn't like an electronic ignition thing, or a turbo thing, or a DOHC thing, or even a VVT thing. It's a conductor thickness thing, and we can all very safely not lose any sleep over it.-)
The advantage is the thickness of the cables. As batteries get bigger and charging speeds increases the cables at the chargers and in the car are going to be as thick as your arm instead of half that thickness.
The other thing to bare in mind is minimum possible cell count. If we are talking 3.7v cells then an 800v system would always need at least 216 cells. If the internal resistance and cooling are good enough then you could get away with 100 cells in a 400v system. Drastically reducing manufacturing costs.
Your numbers for cell count arent usable. Most 400V cars use 96 cells in series or 112 cells (400-450V) or sometimes 84 cells (300-350V actual). 800V cars - probably 192 cells.
Honestly the breaks the model 3 long range needs now (@1000km challenge) would not be long enough for a family trip (especially if you also have dogs with you). The current travel speeds of the benchmark cars (i4, Model3, Model Y etc.) are already good enough. They should focus on bringing that efficiency into other segments now (Vans, economy cars etc.).
Higher voltage allows smaller cables - a bit of weight reduction, or freedom to have longer cable runs (talking to you, Taycan). That 400-to-800V convertor is nuts, 50kW standard / 150kW optional.
You may not be following since they're not in Europe at the moment, but GM's Ultium system switches between 400/800 volts using switches within the battery pack so no conversion is needed. Very little additional weight and best of both worlds today
Sure the losses in the cables are not THAT big. But with 800V, cabeling can be thinner, lighter and cheaper. There are less losses in the inverter which means less cooling needed. All of these effects are small but that's the case for most of the efficeny improvements we see in other areas. The components for a 800V system might still be a bit more expensive compared to a 400V system (but I don't know for sure). But apart from that, I see no reason NOT to go for 800V.
Don't forget that 800 V cables requires better insulation due to higher voltage. Take a look at Ionity charging cables vs Tesla v3 supercharger cables.
@@bjornnyland I think the Ionity cables are bulky as they have the double issue of dealing with both 800V insulation and high current specifications (for 400V). The 800V insulation makes it harder for cable to cool and hence you have to have fancy water cooling jackets etc. 120kW 800V chargers get away with a much simpler air cooled design, but are limited to ~90kW for 400V systems.
When a single speed 400V Tesla Plaid does circles around a 2 speed 800V Porsche Taycan you can see which car has the sensible technology fitted. You also have to consider the charging infrastructure: It is relatively easy and cheap to make 400VDC compared to 800VDC. That a max charge peak is a hyped nonsense figure is clear also , what counts is how many kilometers you can charge in what time in the SOC window of 10%-80%. And finally: While you fast charge you go away and do something like having a meal or do some shopping. That takes 30-50 minutes, which means when the charging is 20mins only you have to interrupt your activity and move the car which is very annoying.
The main point of using 800V is fast charging. By cutting the charging current in half, it allows twice as much power to be pumped though the already unwieldy charging cable and connector.. When fast charging at high powers, even though those cables dissipate only a small fraction of the total charging power, it's still enough that they must have liquid cooling channels in the cable itself. The way to get 350 kW charging without overheating the cable and connector pins is 800V. What I would argue, though, is what car needs 350 kW? I can't imagine needing more that 150 kW. I took a fairly pleasant 1700 mile road trip in my 2022 Nissan LEAF whose Chademo charging was generally 50 kW or less, depending on state-of-charge and battery temperature. For daily level 2 charging, 800V doesn't make much difference. Fast charging is hard on the battery pack, 350 kW is going to be harder than 150 kW. So most EV charging should be L1 or L2. From my perspective, this insane race attempting to make EVs something they are not is counterproductive. Extremely high charge rates should be reserved for commercial vehicles with battery packs which are larger capacity than those used in cars.
To get some perspective on cable size, take a look at the service entrance cable on your house. Many houses today have 200A service at 240V, which is good for 48 kW intermittently, 38.4 kW continuous. At 400V, 350 kW charging rate would require a cable and connectors rated at least 875A, more than 4X the current of normal whole-house residential electric service. I believe they are trying to keep the cable and connectors below 500A rating. A 500A cable and connector is a beast!
It depends where you are. In North America, it max more sense because nearly every >100 kW charger is already 800 V. Also, 800 V makes far more sense for larger batteries, like the new Ultium 200 kWh packs. The Taycan's battery is limited to about 350 A, so for it, it is limited. However, if you were to cut the voltage in half, the battery wouldn't charge as quickly as it could otherwise because the chargers couldn't provide 700 A. Right now, I do think GM is the only one doing it properly, where they are including a switch in their 800 V pack, so it can either charge at 350 V or 700 V. In either configuration, it can accept 500 A, so when a 200 kWh Ultium EV is using a 350 kW charger, it should be able to charge at a true 350 kW (~700 V @ ~500 A). The problem in the United States right now is that it appears that Electrify America is limiting most of their 350 kW chargers to 350 A, which is fine for Porsche and VW, but not many of the newer EVs that are pulling >350 A at either 400 V or 800 V.
Outside the Tesla world, I think 800 V has become an option because CharIn chose to limit CCS 2.0 to 500 A in order to support cheaper/longer/lighter charging cables, and they chose to increase max. voltage to 1000 V for additional power. This is a fair enough thought, but in reality, Supercharger V3 has lighter (if shorter) cables and seems the overall more cost effective system. SomI agree with Bjørn that today 800 V based cars really don‘t have much benefits other than in conjunction with the HPC infrastructure that is limited to 500 A.
Agree, 2019 model 3 is achieving 250kw till 25%. And the new 2022 model 3 performance Bjorn testes last week pulled 250kw till 40%> You don't need 800 volts for that at all. Maybe, internal cabling can be lighter due to lower current. Saving some weight. Has nothing to do with charging speed at all. That's just a marketing spin.
@@Astke As Bjorn said, the battery packs use the same cells. They are just organized different, a 400volt pack has more cells wired parallel than a 800 volt pack. The charging curve is determined to what the car manufacturer is willing to allow. Some (like Porsche) allow for a very high speed knowing it will hurt the battery and give the owner the possibility to set a max rate at 200kw/h. The max charging rate a manufacturer is willing to allow is based on cooling capacity and battery chemistry, these are the deciding factors (and how much warranty a manufacturer dares to give). It has nothing to do with 400 or 800 volt delivery.
@@Astke true... Still, the Model 3 remains the quickest on a 1000km challenge... And every Supercharger has 3 to 6 times slots per charging station. So the question is : is it really beneficial for a Porsche / Kia user as they do not travel faster, they have MUCH less charging slots available because of the cos tof hardware and when they do go on 400C station, they cap at 150kW with quite some charging loss?
@@Astke I am coming from a S 75D with much less range and more range is definitely a huge plus. Especially when you are limited at 300km+ highway range (when you have 400 or more, there is diminishing return). Since when do you have the feeling you can charge on Tesla SC with another car? You are not speaking of the 16 remote stations open to others, do you? Make a North Sud travel of France and tell me how many SC you can use today... It remains very much a huge asset for Tesla owners. Maybe one day all stations will be open but we are very far from it. Again, this is a great car (the Polestar) but for the limited interior space and the 15-20 to 30% higher consumption, you cannot just say that it does not matter. It is definitely a big minus.
@@Astke you mean the eTron GT by 10°C...that took 20mn more? You do not think that the Model 3 will not match it by 10°C less? I remind you that the eTron is not more spacious (it is less actually), it costs... DOUBLE and has a much bigger battery with 800V architecture. All that for what exactly?
@@Astke the e-Tron GT is an amazing car. No doubt. Did I ever say otherwise. EQS is great as well. Both beyond my reach, like many. Oh, and I do not get where you have seen slippery. The 3 Performance pretty much match the Taycan comparable model on circuit (if you do not put ceramic break on the Taycan). You seem to be the fanboy here. That is a different package for sure. I am coming from an Audi so the e-Tron almost feels at home for me... Those legacy interior are just... too much (too many buttons, trims, things here and there,..) while being too little (slow infotainment, complicated UI,...) but yeah, Taycan / e-Tron GT are awesome cars, no doubt.
800v it's mainly good for charging over 300kW, so it's good just for trucks and bigger vehicles. For cars doesn't make much difference (other than a much higher buying price). Today it's just marketing. Also the efficiency gain it's very small so that most of the 800v cars overall are actually less efficient than 400v
It's not just super high charging speeds though. 800V is very useful for reducing the size and complexity of cables needed for the charger. A 120kW charger would need an expensive water jacketed cable to charge a 400V car at full speed whereas with 800V a much simpler 200A cable can be used. Quite a few 120kW chargers I've visited with a 100kW+ charging Polestar get stuck at 90kW due to limited current capacity of cable.
@@benjamindesson5326 if the station is rated at 120kw the cable should handle the full 120kw without any problem I don't think the problem was the cable, it could be that the station has a current limit and your battery has low voltage
@@StefanoFinocchiaro It is the cable, 800V vehicles charge fine on it and the spec sheets of the charger show a 200A cable option and a 300/400A cable option. The spec sheet shows that charger can produce more current if the higher current cable is fitted.
Love technical deep dive videos like this. I guess you can’t even ‘thin out the cables’ on 800V systems because so many established chargers are 400V and you’d be limited to really slow charging speeds. Thanks Bjorn!
An 800 volt motor will have more turns of thinner wire, so though it will run on half the current, it is likely to have twice the resistance, and net, have about the same resistive loss as a 400 volt motor of the same power. Really, the only gain from an 800 volt system is that you can get more charging power given the 500 amp limit of the charging cable and connectors.
I think a 400/800 V parallel/serial switch would make sense. Rather than a stepup DC/DC converter. I appreciate that you need to equalize voltage of the two packs before switching to parallel, but I would believe switching to 400V-mode should give less loss than using step-up-converter. I should be fairly easy to have a Higv-voltag to 12 V convertee that works fine from both 400 and 800 V range.
@@bjornnyland I think another reason to use DC-DC step up, is that charging station can possibly run at 400 V at 125 A, to get 50 kW, and step it up to whatever the battery is at the moment, even if it is as low as 700 V at 71 A. While dual pack would be 350 V and only charge at 43.8 kW, the step up can possibly charge closer to 50 kW at low SOC too.
Pretty much every manufacturer is working on 800V systems right now. That isn't done over night though. The reason you don't see 400V Teslas, BMWs, Mercedes is the fact that they aren't done yet. Not that they don't want to.
I expect Tesla to move to 800V soon with their next generation of vehicles. The cybertruck is the first Tesla vehicle that supports 800V charging. I expect Tesla to follow suit on the rest of their line up only when car refreshes occur. It makes little sense for Tesla to not move to 800V architecture when they can reduce the weight of the HV charging cables in the system and reduce the heat losses in 800V architecture. The challenge of course is still supply chain availability which is growing as more and more legacy auto makers are making EVs with 800V architecture. Keep in mind that what Bjorn is saying its not making much of a difference now because when you charge at Tesla superchargers the 800V capable cars have to derate to 400V charging to be compatible to charge with Tesla superchargers to be compatible with the majority of Tesla fleet and many existing EVs so of course its not charging any faster than the 400V cars. However the Tesla v4 supercharger will be 800V charging capable so I can see the signs of Tesla moving towards 800V charging architecture and will support both 400V and 800V vehicles just like how Tesla is going to move from 12V to 48V LV architecture.
@@erichchan3 yes, I guess you are right. But so many Superchargers are 400V only.., are V4s 800V capable? If not done properly, some 800V cars with the conversion charge quite poorly on 400V chargers (Taycan, for example)… so will they then upgrade thousands of 400V superchargers? Not sure it will happen that soon but I may be wrong… maybe that’s why new model Y maybe delayed a bit as trying to do more than done with model 3?
@@ericvet8b Yes Tesla V4 superchargers are capable of supporting up to 1000V. You do know the Cybertruck is 800V capable right so I see Tesla moving in that direction. Of course the majority of cars are still 400V capable because there wasn't enough supply chain to warrant it. Tesla itself is not enough to warrant the suppliers to build just 800V products. But clearly there are now multiple car manufacturers moving to 800V architecture so I expect Tesla to follow suit going forward.
@@ericvet8b I am not sure if you heard what Bjorn said at 16:50 to 17:40 but he said the fault of the Taycan lies within the converters that Porsche decided to go with. He did say that the Ioniq 5 and other cars have no problem hitting the same power as like a 400V vehicle. Also since Bjorn lives in EU he doesn't know that Electrify America charging stations supports 800V no issue. Also Tesla V4 superchargers are capable of supporting up to 615 kw (up to 1000V and up to 615A). I don't expect Tesla to push its v4 superchargers to that upper limit but its good to know the hardware is capable of supporting it. Currently the v4 superchargers deployed all have v3 power cabinets so the full v4 supercharger buildout has not been realized yet. Again Tesla has produced a 800V vehicle in the Cybertruck so I can see Tesla moving towards that direction to 800V just like they are going to move all their vehicles to 48V LV architecture for its cost and weight benefits. I think charging stations will support both 400V and 800V charging for the foreseeable future. I think the EVSE will key off of the communication pins of the charging cable to determine if they are charging via 400V or 800V.
If battery with 100kWh can 250kW it don't make different if 400V or 800V battery. Battery can 2,5C for example that mean 250Ah@400V with 625A charge current or 125Ah@800V with 312,5A. Tesla SC can about 670A and this make theoretical 270kW@400V possible. If the battery can 4-5C or has 200kWh capacity and can still 2,5-3C then we need more as 250-270kW and with 400V it isn't possible. Today is 800V pure marketing and don't make sence.
I'd love to get your comments on the new Taycan charging curve as it holds 300+kW through 60% and above 200kW through 75%. Porsche even did away with the Eco charging mode because according to the engineers it wasn't needed. Why are the fastest/best charging vehicles (Lucid/Porsche/Kia/Hyundai) all 800+V when the science/physics says that shouldn't matter?
EVs are in the same patterns for old computers, there was IBM and PC's. At the moment Tesla like a PC and the old car manufacturers are like old IBM. When we were upgrading PC's there was CPU socket and Northbridge Architecture in the mainboards. So the future of EV's can likely be Battery-BMS-Distribution architecture, so there can be TESLA comptiable parts such as batteries. Tesla can provide a extensible architecture like PCiExpress in the computers, so you may change parts according to compatible parts.
Björn - the 800 V chargers will only become more commonplace if there are cars utilizing them. So, we do need to have 800 V cars around and they need to become more popular. I agree with your points on the video, but you could have also discussed why this needs to happen. The hyundai/kia motor inverter based system seems to be a very good design, hope more manufacturers go that way. The worst case scenario is we are stuck with 400-450V based systems for 20 years. Second point - battery heat tolerance. Arent new batteries coming with much larger surface area in battery cell terminal? This should make it easier to use high currents for individual cells? You did not discuss this. Although granted, such batteries are probably 7-10 years in the future for commercial applications. Is LFP going to change anything?
Many state of the art axial flux motors perform better at higher voltages (600-800V instead of 400). Their higher performance/weight ratio and efficiency is an additional incentive to use an 800V architecture. Beside you can use a smaller inverter.
will tesla cyber truck be 800v? does this mean tesla will need to convert chargers or manufacture new chargers? will they combine chargers, also the tesla truck (lorry)will be 800v or 1000v
They've said they'll build new chargers. They're called "megacharger" and the first ones were installed in January. Details not yet released. (that I've seen)
is 800v potentially a little damaging short term - several chargers seem to use kw headline figures based on 800v. And if most cars are 400v they won't get near that kw rate and can be disappointed?
EV6 and Ioniq 5 can charge at 50 kW already at low state of charge on 125 A restricted cables on 50 kW 400 V fast chargers. Also practical advantage: there are 150 kW HPC chargers that have 250 A cables, which means you can charge 150 kW with an 800 V car but only 100 kW with a 400 V car. I don't really know any 400 V chargers with more than 50 kW here in Germany except superchargers. I'm sure there are some but they are super rare. And 50 kW chargers are getting more and more replaced. I think in 2 years already we'll be at 98% 800 V chargers.
It is heat that kills the battery, so it seems cyndrical cells seem to handle high heat such as Tesla uses, verses pouch type that the Tycan has, I would say both would suffer from cell degradation using high DC charging rates.
It is not the heat loss but the charging rate is higher with 800 volt pack verses 400 volt, have yet to see a 400 volt pack do a 10 to 80 % charge in under 20 minutes
I kind of agree, but does it mean that the 800V cars have a platform that need less change (only remove the 400V features) in the future builds? And are these platforms better prepared for the future because the brands now already get experience with the 800V system, which is not bad since Hyundai have a lot of other lessons to learn (How to deliver a car within 12 month, how to predict that your EV will be very populair and how to scale up and ship). Don't hear me wrong, I love the way Tesla is can change a car within 12 months and that even in resource shortage you can get their main car in a couple of months.
800 volt EV makes for the user sense only when charged with 800 volt, as to achive a certain kW only half the amp is needed. For the car maker, its half the cables on the 800volt side to charge and feed the motors. 800 volt has been used in marketing as magic. There is more magic in reducing mecanical friction, as a few 400 volts have achieved No disadvantage in the korean 800 volt. Neither to the user or the battery celles.
Problem with 400v cars is now everyone and their cousin need 500a chargers and in America there are only 1 working electrify America ea charger per 50 miles and even then a lot are current derated due to temperature sensors failing. Look at plugshare in California, only 40 percent of the meager 350 kw stations even work. This is not a problem for tesla because they figured out how to install 8 v3 chargers at the pace EA installs one and deliver huge current to their cars. If chargers for ccs were like that I would agree with Bjorn but the current state of chargers means that a 150 kw station (the norm here) delivers 173 kw to an ev6 (nearly to 80 percent) and that same charger does 130 kw to low voltage cars due to current limits.
the E-GMP 800v system has no compromise - you get the best of both worlds, if you have an 800v charger then it can go as fast as the battery allows, if you have a 400v then it can take 250kW, which is a very respectable figure, and all this is done without additional hardware as it uses the motor's inverter to boost. You need an inverter regardless. Quit quoting the Taycan's 800v system it's trash, quote the E-GMP one.
you dont even step up. Because between the 3 Phases you have the correct output after the Transformation. And Higher Voltage in the Battery Pack means also double the internal Resitance when you not double the Power Capcity. I can‘t really belive what Bjørn told that 800V have less charging loss.
@@groepi1972 in serial you already have 2x the power (voltage 2x higher - userfull power 2x higher ). 1/2 the current brings power back to previous value. Cable losses are reduced (maybe down to 1/4 if wires are as thick or down to 1/2 if wires are 1/2 as thick)
@@volodumurkalunyak4651 yes and double of internal Restistance for the battery pack. That means more heat on charging and discharging. The only benfit of higher voltage is that you don‘t need thicker Cabels. And don‘t forget the Grid have only 400V So you need DCDC Converter for 800 V. And its also a Problem for some 800 V Cars to charge at 400V. Let us see in a few years. We becomme more current for charging faster at 400V thats will be the future. On Gernan Autobahn you need high speed charging. But there will be a Tempolimit sooner or later …..
Nice analysis, unfortunately missing key insights like you need a lot less copper in order to create 800v systems. We are in a phase where the scale of electric cars is exponentially increasing. Like you said, 2% is not a lot of losses, but 2% of all charging everywhere is soooo much... You need to think of the big picture!
What about the 2 % charging loss when charging at 400 V? Did you totally forget about that? And we don't know if it's even 2 % or even higher when charging at 150 kW 400 V.
@@bjornnyland interesting take with the what about-ism. As an owner of an ioniq 5 I will probably never experience the losses, as ionity network is more than enough for any of the long distance travels. But since the 2% efficency loss is purely speculation in that case. I suspect this will be the experience for nearly all ioniq 5 owners. I cant speak for others, but it's a definite calculatable difference to all the teslas losing the 2% always.
I think that a shared architecture and standardization of battery packs are missing in EVs at the moment. From single to 3 battery packs with a decent cooling systems (400V 150kw) two paralelized sockets may be a solution without frying the chemistry. Lets say a battery package of 50kW is a standardized and 400V 150kW BMS module with one socket is a standard. And there can be cars with 50kWh(single pack)/100kWh(w2pack)/150kWh(w 3packs) as an option. At the moment there is a tons of an option for EV batteries and different architectures which is not sustainable.
Why are you celebrating Teslas 250 kw charging at the charger in the recent model 3 Performance video and at the same time you say that Porsche roasts its batteries with 270 kw charging? The Tycan has a bigger batted pack, so if the Tycan roasts its batteries, Tesla will roast its batteries twice as fast? Hope you can follow me. Other than that very interesting! Thank you!
Tesla only allows 250 kW below 10 % for most cars. Many Model 3/Y can't even hit 250 kW and around 200-220 kW is max. Taycan keeps the 265 kW until 30 %, 250 kW until 50 % and 154 kW until 73 %. But the eco charging option is way slower. Watch this video: ruclips.net/video/4J-XEFSps4k/видео.html
Are you talking about there is little difference in charging time between 400v and 800v chargers at an 800v (or above) station. The Rigian CEO disagrees with you. And so does Inside evs. In their article, Nextmove's tests showed that the Taycan isn't able to charge at the advertised 270 kW rate, however, it's not far off. The publication recorded a peak around 250 kW. Nonetheless, the Taycan proved to charge a bit quicker than Porsche's numbers suggest. After spending some time collecting charging data from the Taycan, nextmove compared it to Model 3 charging speed tests. In the end, the Taycan added more range per hour than the Model 3 even when the Tesla was charging at a V3 Supercharger. I suspect the shape of the curve is the most important element- but I believe if a Taycan is charging on an 800 charger it will beat the Tesla- or was your point that there are not many 800v chargers.
My understanding is electric motors are more efficient at higher voltages. As far as EVs; the manufacturers can choose whatever architecture they want for each car designed. I'm sure many factors play a role and in certain EV applications, higher may not always be better:)
@@matthewwiemken7293 Looked a bit more into this and it appears at least the Porsche Taycan does have 800V motors. They could still internally be 400V but didn’t find anything that detailed. I know the Hyndai/Kia cars have 400V motors with 800V packs.
I think that you are just trying to justify your previous comment about no point of having an 800 V architecture, rather than considering the pro and cons and coming up with a balanced view. I disagree with a lot of what you are saying. With an 800V system you halve the heat losses in the cabling and motor and any other component running at 800V, or you can reduce the weight the components by reducing the amount of copper by half. This means less weight and cost. I have had a Taycan in the UK for 2 years and have never encountered a single 400V charger, so have never had my charging limited to 50kW (i don't have the addition 150kW charging unit fitted), so for me your slow charging comments on a 400V charger are irrelevant.
The Korean 800 V cars can do V2G. So if the power price is high during peek hours in the afternoon the the V2G controller can take energy from the car. Then there is at least 2 benefits: Lower energy bill and less stress on the grid. The grid operator should give you extra cheap transfer bill. So you Bjørn need one V2G car in your new house to demonstrate. Then you are in the same game as Robert Llewellyn. Now You Know!
@@andrei_dk Hmm. But not all EV is made to give away energy via V2Load. Do you agree? If we have inaf V2G storeage then it can help the grid. Im no expert in V2G controller but the device controll the flow from PV, batterypack, EV battery or the grid. So it is not in the EV.
EV with CHAdeMO plug can do V2Load and than use V2G system. Testing in bigger area in the Nederland. So that may be some Nissan, some Korean EV and the triplets.
Another good point I forgot to mention is heat scavenging and Tesla octovalve. Heat loss in motor(s), battery, inverter and other electronics inside the car can be captured and used for heating up battery or cabin. This also applies to 800 V cars if they have implemented it. This means that the slightly increased heat loss in 400 V systems can be used for something useful rather than just dumped outside. But this also means that the heat loss generated in 400 V - 800 V conversion in Taycan/Ioniq/EV6 can also be used for heating up other components in the car. It boils down to how well car manufacturers can utilize the heat.
My claim is that Tesla with their octovalve is the best when it comes to exactly that. A well-designed 400 V car can be more efficient than a badly designed 800 V car.
But what if Tesla designed that 800V?
Same like heatpump. We dont need heatpump in tesla. After first heatpump: its the best 🤣
Heat lost is resistive heat so isn't that less efficient than using that same power that would be lost as heat to power a heat pump?
I'm glad that GM implemented this heat scavenging in their Ultium platform. Are you going to review a Cadillac Lyriq? Maybe one made in China? Thanks for your work !
@@rogerstarkey5390 Yeah, I guess my real question is. Is there any possibility that the Cadillac Lyriq will find its way to Norway. :)
In Electrical Engineering, 400V and 800V are both low voltages, the insulation, power electronics etc are not goona ba that much different. The difference between 400A and 800A (respective current need for 300+kw charging) is gonna be much more significant in terms of electrical system design. Heat loss is squared, but you don't need four times more insulation for double the voltage.
50kw chargers should be put at supermarkets, shops, galleries, cinemas etc places where you'd leave your car for around 1h
50 kW chargers should be designed to work with 800 V.
Which movie are you gonna watch at the cinema for an hour?
dude the grid in most cities can't take that many chargers at the moment.
@@dragospahontu they should just have cheaper 400v 3 phase 11/22kw chargers.. if your car needs quick charging while you are at the cinema you've driven way too far to watch a movie :)
@@dragospahontu look at a map and check out Amsterdam or Zwolle. There are HUNDREDS
bjorn, as an old, retired, automotive engineer i agree with your point of view 100%. one principal of engineering that i didn't hear you mention was the law of diminishing returns. so any voltage can be used to power an ev. from 3.7 up to 10,000 volts. if you plot the efficiency versus system manufacturing cost, my guess, and i must stress this my guess, is that there would be a local minimum around 400-500 volts, where the manufacturing costs for an 800 volt system is higher than that of a 400 volt system.
Hey Bjørn,
Very interesting thoughts - thanks for the video!
Perhaps some counter arguments in favour of 800V, if I may;
1) Cost.
We see evidence that 800V architecture is actually already cheaper than 400V platforms... e.g. on Tesla's prior earnings call Elon and Drew said switching
to 800V for Model3 and ModelY would save about ~$100 per vehicle. However, at the moment their volumes do not make sense to switch considering all the sunk cost in 400V components and supply chain. Basically it would cost too much to change over at this time... but if they were starting a new platform, its obvious 800V would be the choice.
That said, its pretty clear Cybertruck and Semi will be 800V, so I think we'll see R&D costs of 800V tech trickle down and be applied.
For example, if Tesla ever get to 2M vehicle production PA, $100 x 2M vehicles = $200M savings per year which is not insignificant
Another good indication of lower cost is the BYD eMotion3.0 platform going 800V for mass market vehicles. Even their new compact BYD Dolphin which has max charge rate of 60kW is based on this 800V platform rather than their 400V platform.
Pretty solid evidence this decision is based solely on cost (most important factor in China), and not charging speed (60kW is obviously easy to do on 400V)... and this cost saving includes the 400V-800V translation / backwards compatibility.
2) Technology.
You highlighted in the video Hyundai/Kia's method of using the traction inverter electronics to do the 400V-800V translation. This revolutionary technology means the cost of backwards compatibility is basically $0 (everything you need is already included in the powertrain)
A few in the industry started calling this the Onboard DC charger (OBDC), and in my opinion, it is revolutionary. I see pretty much every 800V platform moving in this direction (e.g. Hyundai, Kia, BYD , XPENG, Volvo, etc and probably even Porsche/Audi on their refresh PPE).
So not only is the OBDC cheaper (its free), it allows much fast charging over voltage doubling method like Taycan...
for example, you note in your testing that Taycan only gets like ~38kW on a 50kW charger, whereas IONIQ5 with OBDC gets a constant 50kW... e.g. 30% faster charging.
This is because the IONIQ5 can request max voltage and therefore max power, and does the charging onboard.
The same applies to 400V EVs without this OBDC... e.g. a Model 3 capable of 250kW charging also charges
Stefan, I'm using the information from your reply in a interview tomorrow, wish me the best of success 😁👌
@@daviddavid-up1jc good luck! Please post link here afterwards :)
Korean 800v kicks ass for the lord on slow(50-100kW) chargers here in Poland, where other cars are limited by amperage, Koreans gets full charger speed...
You are correct, we are still mostly limited by the individual cell C rate, and its heat rejection efficacy. Doesn't make a lot sense to go to higher voltages until that is improved. You gain a % or two through lower amperage in charging and powertrain circuitry, but not a ton as you said. There's no real downside though other than making sure components are rated as such, so if they want to be on 800v platform, might as well.
However, huge battery packs well over 100kWh will benefit from higher system voltage due to the sheer number of cells.
All cars could have an “eco-charge” option. Even Tesla you are degrading battery with much supercharging.
If you know your going to stay a place for 45 minutes, why fry the battery when it’s not necessary.
Agreed.
Tesla wants you to charge fast and make room for newcomers. If so many people went for a 1h dinner all stalls would be taken for too long when using eco mode.
@@bjornnyland Bjorn, maybe you know. Is the build-in charger more effective at 12kw or at 5kw? In the beginning i was charging my model 3 at 5kw at home but then realized that a computer power supply with a gold rating only achieves this at 80% load, then the load is much lower, the computer PSU becomes far less efficient. I then assumed this is also true for the build-in charger? (especially in the winter as a bit more heat in the battery might make the charging more efficient as well?
Many thanks for your thoughts!
@@davids.6671 Thanks !
Ah fast charging at a slow rate? You don't need 800V tech for that. Also people waiting will not be happy for eco mode charging. Just use a 50KW charger, that is gentle to your battery. In a Tesla S/X: 125A : 74 cells is just 1.7A per cell which is below 1C.
Well, my real world experience in Germany and Austria after 25.000 km in an Audi e-tron GT ist that in ideal cases (IONITY oder FASTNET) I average 177kw charging between 5-85% so my fast charge takes 15-20 min. I drove the BMW i4 M50 for 1.500 km that sucks completely. The 10-80% took the BMW 45-60 min. and after a short peak at 170kw it drops quickly to 50-60kw and stays there all the way till 80% averaging way below 100kw! The Mercedes EQE 43 I drove for approx. 1.200 km is better than the BMW but still worse than the Audi as it kept the 160-170kw peak longer and averages slightly above 100kw. Nevertheless it also took the car 30-35 min to charge from 10-80%. On long trips if you charge 1-3 times that makes a huge difference!
For cars with battery packs under 100 kwh, it doesn't make sense to switch to 800v. If the system is initially designed there, fine, but for Tesla, makes no sense to switch their cars over. For vehicles with much larger packs >100kwh, 800v will be helpful as you need a lot more watts to charge in the same timeframe. For large trucks, semi's, etc. 800v or more makes sense. For small cars like the Model Y and 3, it makes no sense to switch.
It makes sense, the car can either have thinner cables and be lighter/cheaper to manufacture, have less power losses or a combination of both.
But 400v is smaller, lighter and requires less power management than 800v. So it makes even for semis and trucks sense to use 400-450v. Adding to that you cant get the full power on a 400v charger with a 800v car. And there are more 400v cars because they are cheaper to make and because of that the mass of cars.
@@gforcefabi Explain how 400v is smaller, lighter and requires less power management?
@@gforcefabi Like Bjørn explains in the video, what is in a 400/800 pack does not change given they are same capacity, only how stuff is internally connected.
If going by 4V/cell, you'd need 200 in series to make a 800V pack of say 60kWh. 100 cells in series would make a 400V pack, but then you'd only have 30kWh of capacity, so you'd need to add another 100 in parallel to make capacity equal.
At the end of the day, either 60kWh pack would still have the same 200 cells, and therefore weigh the same, and need the same degree of battery management.
@@gforcefabi you are totally wrong.
Try to understand what Bjørn is saying. U=RI
The main advantage at 800 V is that you can get the same power as 400 V using cables with smaller diameter. The diameter of cable is determined by current, therefore you can use less material in the system. The charging stations could deliver much power without using liquid cooling in cables.
I suggest that you watch the video first. I discuss this.
Not just the cables. 800V allow for thinner coiling wires in the stator of the Taycan’s motor that save weight. Then you can go and put more luxury and safety features in the car.
@@AndrewNC22 yes but if you have to be backwards compatible with 400V are you really saving weight?
@@girogiacomo but you are saving the cost of the copper wire.
@@JamesWindland it's probably negligible... in the battery pack you probably have to use the same amount and in the rest of the veichle i don't think it would be that costly... remember... you have to have stronger ICs on 800V... 800V would be great in heavy veichles like cybertruck, hummer ev and f150 and by the time it will be in 99% of chargers it should be in every car but that time is not today, like bjørn said
My guess would be that the Korean cars do it by running the inverter and rectifier (normally for regen) at the same time. The inverter side takes in the 400VDC, turns it into AC (possibly both share the task of upping the voltage, so it sends out say 550VAC), but instead of driving the motor, sends it straight to the rectifier/regen side to be converted into 700VDC.
If this is the case, it would be less efficient than the Taycan's DC-DC conversion, but less physically wasteful as it is using hardware that is already in the car anyways, rather than adding an extra part.
Using a "pure" inverter you cannot step up the voltage - you'd need to add a transformer for that (well, I guess technically there are other ways, but AFAIK a small transformer is the most efficient way).
Watching the beautiful Norwegian scenery go by while listening to Bjørn's thoughtful commentary was a real treat. I do agree with Bjørn's conclusions and happily drive my 400 V Teslas while looking forward to an 800-900 V future, thanks to forward thinking engineers at Porsche, Lucid, and Hyundai.
As a car manufacturer expecting to adopt 800 volts in the future, I can just start with 800 anyways to gather experience. Porsche is not a company which sticks with old stuff because it is cheaper. It tries to provide customers with the best tech available.
exactly
It provides customers with marketing over function. Porsche clients like to brag on a party, this enables them.
The 2 speed gearbox is just nonsense as is the Turbo name in an EV. Efficiency is KING and the cheaper Plaid drives circles around a Taycan anyway.
Not really.
According to information received by Tesla enthusiast Sawyer Merritt, the automaker plans to increase V3 Supercharging speeds to 324kW in the third quarter of this year. With a 400V system.
My EV6 holds flat 170kw up to 80%, and peaks at 241kw. I thought this was mostly because it has 800v so it has less overheating and can push harder. But now I am confused. If the batteries are all 3.7v, which makes sense, then why are the egmp cars like EV6 and Ioniq 5 so much faster at charging than all the non-tesla and even faster at a higher SOC than the Tesla cars? I don't know.
I looked up it up and the Electrify America chargers in the US charge at up to 350A at 1000v, so maybe that is why my experience is good with the 800v cars in the USA.
Probably they are 350A at 400V also, which makes for an advantage for 800V cars.
Very simple, the answer lies in 2 aspects: thermal management, and low internal resistance. The eGMP cells have a low resistance and are the first pouch cells to be directly in contact by the bottom to the gap filler and cooling plate.
Another aspect is battery chemistry. Then, in the end, the manufacturer sets the max speed, however they feel like.
Hyundai is sacrificing their batteries, look at the degradation of the regular ioniq bjorn tested.
If they don't have a superior heating/cooling and battery chemistry systems and the manufacturers are pushing higher charging speed, expect less battery life, than manufacturers that are charging at lower rates.
People are focused too much on charging speed, manufacturers aim to please, but it's generally at the cost of the battery life. As end users we will only find out 3-7 years down the line.
I charge at the lowest possible rate I can live with. (I have no choice when using high speed chargers - but avoid them as much as I can)
The thing about 800v systems is that it is solving a problem we don't really have ... until (and if) we get really big battery packs.
Good points. Since most 400 volt stations really peak around 480-500v, I too am in favor of 450-500v battery pack for personal vehicles and save 800v for larger vehicles like trucks and buses.
Almost all chargers over 50kW support up to 1000V. There is no drawback in 800V battery packs.
@@holl0r Sure there is: cost. The electronics are more expensive in an 800V pack.
@@MacGuyver85 That depends on the design of the pack and the charging infrastructure. The porsche solution is expensive, heavy and inefficient. But it's also pretty damn old by now. Kia/Hyundai does it better and future cars won't need a transformer at all.
@@MacGuyver85 I am pretty confident that component cost is really small part of the total cost -> could be close to meaningless increase.
@@mho0 The porsche solution IS expensive. But it's really old by now. The goal is to get rid of active components like converters. In general, component cost is the major factor to be considered. Everything you can solve with more simple components will be done the cheaper way even if software development costs skyrocket, simply because development cost is a one time investment, while manufacturing costs scale with volume.
I disagree. The current CCS spec (Edition 4 ,NOT Version 2, IEC 62196-1:2022) goes up to 800A and 1500V. But with so many amps you need cooling. With 800V charging up to 200kW without cooling could be possible.
HPCs that don't support >500V are very rare. Generally chargers are more amperage limited thant voltage limited. For that reason alone 800V makes sense.
21:35
Completely agree, the cost difference between a 120kW charger with a 200A cable vs a higher current (water cooled jacket etc.) cable is significant. Hence so many 120kW chargers fail to deliver above 80kW on 400V cars. 800V cars don't suffer from this problem at all.
The units (in north America) we call 340 kW dcfast are rated at 1000 volts to supply 340 amps. So a 740 volt (voltage depending on state of charge) battery could take up to 250 kW. There are 500 amp units out there too. Not cheap to build and provsion I'm sure. Back in the fall of 2019 in Canada the Kia Rep said they were building 800 volt architecture in their future designs. They did.. Beats the crap out of a 40 kW to up to max 74 kW Niro EV charge rate.
@@benjamindesson5326 a 200 amp charger can only do 80 kW at 400 volts. 😂
According to information received by Tesla enthusiast Sawyer Merritt, the automaker (Tesla) plans to increase V3 Supercharging speeds to 324kW in the third quarter of this year.
On a 400V system.
Great video Bjorn. I think it's like the age-old question - "Which came first, the Chicken or the Egg?" - Same with 800V. Either the cars move there 1st and the infrastructure catches up or we wait for infrastructure and the the cars catch-up. Here is the US, we have issues with the (non-Tesla) charging network - a lot of 50kW chargers, not enough chargers, out-of-order chargers, etc. so the wait for the infrastructure may be longer than in Europe.
Thanks for sharing your insight.
I pointed out in this video that the 800 V chargers are backwards compatible with 400 V cars. This means that we can start rolling out 800 V chargers and still make 400 V cars until the battery packs are large enough to where 800 V makes more sense.
@@bjornnyland Agreed... just saying the opposite is also true - as is being done. Make 800V vehicles that can charge off the 400V infrastructure until the Infrastructure catches up. Not arguing, just stating both concepts have some merit.
But adding 800 V chargers doesn't give any disadvantage to 400 V cars charging on them. But making 800 V cars that needs to charge on 400 V chargers is a disadvantage.
One more advantage with 800V is the charger limitation to 500A (not with SuC of course, but all the others). Taycan would be unable to charge with >200kW on a 500A-limited charger.
I already discussed this in the video.
Looking forward to see how these early adopter of 800v battery degrade over time
Reminds me of the discussion of household voltage. 220VDC became European standard after WWII since the overall system had been destroyed and needed to be rebuilt. The US stuck with 110/120VDC, even though the physics suggested higher voltage would be better. A similar argument would have had Europe adopt 60 hz, but it was too late to shift from 50hz. Standardization sometimes does not end on the best tech.
The higher the frequency means also loss in the wires from the transformer to the house.
@@GameOver556 Almost all houses in the US have 240 V already (it's a nominal 240 & 120 here not 220 & 110 like most people say) but it just isn't used for most common outlets. 240 V is only used for high power devices like electric ovens, electric central AC/heat, clothes dryer, and hot water heater.
I don't think common household appliance usage will ever switch to 240 V. Yes, nearly all devices today can accept 240 V with universal switching power supplies but there is no compelling reason to change.
@@GameOver556 Sorry for the late reply.
15 amp 120 V installs in the US use 14 AWG wire, which is 2.5 mm2. 20 amp 120 V installs use 12 AWG (4 mm2) or 10 AWG (6 mm2).
On a side point (at 16:30) all DC - DC converters consist of an inverter followed by a transformer rectifier. If it is regulated then the regulation can be done at the inverter or by a buck regulator following the rectifier.
DC-DC converters does NOT need to have an whole inverter and transformer. Buck (also boost) regulator is a type of a DC-DC converter.
You do propose chaining 2 DC-DC converters first one - isolated non regulated, second one non isolated regulated buck converter.
That is atrocious, why even use isolated converter (with a transformer) and why 2 stages (roughfly 2x power dissipation)???
@@volodumurkalunyak4651 I agree. There is no need for isolation and a boost regulator will suffice.
I think EVs need to be future ready because they have the potential to last a looong time. If I buy a car in 2024, I would prefer 800V. I have designed RC cars for inter college competitions and I know how easy many things are if you have a higher voltage system.
I already pointed out this in the video. 400 V cars can charge at 800 V chargers. So today's 400 V cars are already future proof.
21:35
@@bjornnyland agree with everything but your comment about 400V chargers, why scrap all the existing 400V infrastructure when you acknowledge that Hyundai/Kia E-GMP platform has cost effectively resolved DC-DC conversion (unlikely Porsche)? Apparently Cybertruck will be 900V, it will have #OBDC to leverage existing Superchargers. With onboard DC charger V4 Superchargers can be simplified.
Great conclusions. Min 22. make cars more efficient (less weight, better aerodynamic, less battery, etc), not a bigger battery. (Follow the glider principles, not the Hummer way).
For real.
That's where it's really at. If you cut the consumption by 50% you've magically doubled the charge rate of every outlet on earth.
Your arguments are all correct. But you need also to see it from the perspective of the charger companies. Why should they build 800V chargers if there are no 800V cars? If you want to ultimately switch to 800V someone needs to provide demand for it and the trucks are not really providing much demand for manufacturers to switch to 800V. It's the old chicken-egg-problem. Someone needs to start to base everything on 800V systems, otherwise they will not ultimately switch to 800V architecture.
You are presuming that 800V chargers are better, when they are not. By your presumption, then 1600V would be even better. The hope is that future battery chemistry will be smaller packs, with higher energy density, not bigger battery packs, that require higher voltage.
As I already mentioned, many HPCs like Alpitronic (Hypercharger), Tritium and ABB are already 800 V only.
an 800V system definitely makes sense, if only for the cabling material reduction 🤷♂️
You are right. With current battery tech, 800V is not that useful for cars. The only benefit now is with the lower current, you can get away with thinner high current cables used in the car. For trucks, bus and ferries however, you probably want 800V or even 1,000V because their huge battery pack can handle the extra energy and there is a limit on how thick a cable can practically be in term of the volume occupied in the vehicle, of cost (thick cables are very expensive) and the fact that the fast charger cable needs to be thin enough so it can be plugged and unplugged using human hands even at -35°C. Ideally future fast chargers should have a DC to DC converter providing the voltage needed by a charging vehicle instead of a fixed voltage. From what I heard, the Tesla Semi will questionably use two 400V battery packs instead of a 800V one. To charge you will have to use two plugs from two different chargers on top of each other.
But the installations cost enough that its probably best to future proof them a bit before the cars arrive that can use them. Then the old chargers must be upgraded in the future. But as one of your American viewers I appreciate your explaining this since our schools don't teach anything that is actually useful in the real world.
Bjørn, you should start a podcast. Just upload the exact same audio on Spotify etc.
The clouds in the video looks soo unreal
Polarizing filter ftw.
thank you so much, this info is eye opening!
I was wondering why BYD is considering to implement the 800v system in the future
Without watching the entire video I think you need to take a look at how the power delivery is. With higher voltage you get more W.h through one cable of a specific diameter. It's not about loss, its about saving copper, weight, lowering cost and needing less infrastructure.
I suggest that you watch the video first. I discuss this.
Elon musk said that equipment per car cost 50-100$ less if 800v. Thats much, much less than money that would be spend on upgrading superchargers.
@@bjornnyland And yet you kept talking about resistance and heat. I did watch 90% and while you touched the subject I believe the reason is cost. It's all about the money, always is. And since this is the Internet and the vocal delivery benefits are lost, I want you to know that I am not trolling and all is cool as a cucumber.
I think it makes sense to develop new platforms with 800v architecture. If it is as you say, that 800v will make sense in five years, the E-GMP platform is probably more future proof than MEB even if there is no to little advantage for the cars produced today
I don't think it requires a whole new platform to switch from 400 to 800V. Just replace some components (inverter and cabeling mainly)
Thanks for the explanation.
Does 800v mean that cable sizes within the car can be smaller and hense cheaper cabling? less copper used inthe cable harnesses
It’s not all about charging. 800V makes sense for performance. If you pull Less amps from the battery to achieve the same power, it will take longer to overheat. This is why Taycan can launch consistently for longer.
Wrong, the cell voltage is around 3,8V.
Then what about the Tesla Plaid with 400v? It's just about engineering. Porsche, Audi, Lucid etc just found a easier way out with 800v, might be because of lack of engineering. Now 4680 cells will roll out with 400v and it will be able to charge with +370kW. Of course 800v is better for performance and charging but not for the time/tech we got in today's cars, tesla shows it isn't necessary with a 800v yet.
@@sworksm552 It's not all about the cells. Motor and inverter are also important and they benefit from higher voltages.
Incorrect. Model 3 Performance can also launch consistently for longer. Porsche (intentionally?) compared Taycan against older Model S tech. But compared against more modern Model 3 tech, then the Porsche had no real advantage.
ruclips.net/video/YVaebcsHNFU/видео.html
Isn’t motor running on 800V or thereabout?
Say you have a 100kW charge/discharge on a battery pack. One is 370V 200 cells, 2p100s. Other is 200 cells 1p200s at 740V. For battery pack 1 this means 270amps at 100kw, for battery pack 2 this is 135amps.
Now for the cells, in both battery packs, the internal resistances are the same. (At 0,001ohm per cell, total of 200 cells is 0,2 ohms for the 1p200s, and 2x 0,1 in paralell is 0,05 ohms for the 2p100s. at 100kW this means 270x270x0,05= 3.6Kilowatts of loss for the 340V pack. (P=I2xR) and for 135x135x0,2= 3.6kilowatts of continious loss for the 740V pack. (Obviously cell internal resistance for this example is exaturated) so far we have no additional gains.
The cells in series, the resistance you can just add up, in parallel you cannot. (In my example, just 2 parallel of the same value is the same, so in reality it becomes more complex), but losses increase a lot with current, magnified by additional heat in the cells and copper. More cells in series, means more voltage, which translates to less current per cell, which is less losses per cell.
You can reverse this by saying that both battery pack needs to deliver 135amps for each series, so the 1p200s 740v pack delivers 135amps, with 200 cells, and the 2p100s delivers 135 amps per parallel string with 100 series each. 740V is 0,67 amps per cell, 340V is 1,35amps per cell.
Just comparing Tycan and Model3 is kind of a short cornering, because of different battery capacity, the Tycan has 30%-ish more capacity. So for the same voltage, it has more in paralell. So the total internal resistance of the pack is always higher as your capacity increases.
Agreed 100%. 800 volt will become more important with larger packs >150 kWh that can charge at >300 kW. In those situations, it will be important to keep the amps down in the charging equipment. But for the cars we have today, 800 volts has no practical advantage.
Finally some validation for what I've been thinking!
You are correct.. No actual need in normal cars yet but its good some cars has 800 volt, that will make sure chargers are 800 volt and futute proof.
I'm a chartered Electrical Engineer, what Bjorn says is 100% correct in all details. 800v saves heat loses in some parts of the charging equipment
Agree efficiency ionic classic 28 was my best, model 3 SR+ and now have a tesla model s 75- today i did nearly 1000km in UK and was achieving 240wh/mile- lowest was 180wh/mile pretty good for a 5 year old Tesla. they are still more efficient than lots of newer ev's. The new ionic 5 has gone backwards with efficiency- thats why love mini electric and new model 3 LFP.
Compare apples to apples... Bad comparison
Great thoughts on that topic. Sure a 3ph inverter can be used as a DC DC converter, but what out, looking at peak power of the rear drive unit does not mean that it is a power that can be maintained for a consistent charging session. Like this podcast format !
You just nailed it. 800V doesn't benefit you today but in the future it is a no brainer. IMO
If we boil it all down, the only thing 800V does is fiddle with the balance between conductor thickness and (very small) resistive losses. It isn't like an electronic ignition thing, or a turbo thing, or a DOHC thing, or even a VVT thing. It's a conductor thickness thing, and we can all very safely not lose any sleep over it.-)
The advantage is the thickness of the cables. As batteries get bigger and charging speeds increases the cables at the chargers and in the car are going to be as thick as your arm instead of half that thickness.
And as of today, the batteries are simply not big enough.
But Tesla V3 cables are much easier to use as Ionity cables
@@sworksm552 yes the ionity are 350kw so thicker
@@sworksm552 The Tesla cables are very short. If they were 800V they could be much longer without losing anything.
Nice video. Bjørn havent you hear nothing about getting to realy do a big test of the HONGQI E-HS9 get ?
The other thing to bare in mind is minimum possible cell count. If we are talking 3.7v cells then an 800v system would always need at least 216 cells. If the internal resistance and cooling are good enough then you could get away with 100 cells in a 400v system. Drastically reducing manufacturing costs.
Your numbers for cell count arent usable. Most 400V cars use 96 cells in series or 112 cells (400-450V) or sometimes 84 cells (300-350V actual). 800V cars - probably 192 cells.
Honestly the breaks the model 3 long range needs now (@1000km challenge) would not be long enough for a family trip (especially if you also have dogs with you). The current travel speeds of the benchmark cars (i4, Model3, Model Y etc.) are already good enough.
They should focus on bringing that efficiency into other segments now (Vans, economy cars etc.).
Higher voltage allows smaller cables - a bit of weight reduction, or freedom to have longer cable runs (talking to you, Taycan). That 400-to-800V convertor is nuts, 50kW standard / 150kW optional.
You may not be following since they're not in Europe at the moment, but GM's Ultium system switches between 400/800 volts using switches within the battery pack so no conversion is needed. Very little additional weight and best of both worlds today
Sure the losses in the cables are not THAT big. But with 800V, cabeling can be thinner, lighter and cheaper. There are less losses in the inverter which means less cooling needed. All of these effects are small but that's the case for most of the efficeny improvements we see in other areas. The components for a 800V system might still be a bit more expensive compared to a 400V system (but I don't know for sure). But apart from that, I see no reason NOT to go for 800V.
Don't forget that 800 V cables requires better insulation due to higher voltage. Take a look at Ionity charging cables vs Tesla v3 supercharger cables.
@@bjornnyland That's true but plastic is cheaper and lighter than copper and we are talking about millimeters only.
@@bjornnyland I think the Ionity cables are bulky as they have the double issue of dealing with both 800V insulation and high current specifications (for 400V).
The 800V insulation makes it harder for cable to cool and hence you have to have fancy water cooling jackets etc.
120kW 800V chargers get away with a much simpler air cooled design, but are limited to ~90kW for 400V systems.
Semiconductors have much more losses at higher voltages ⚡️
When a single speed 400V Tesla Plaid does circles around a 2 speed 800V Porsche Taycan you can see which car has the sensible technology fitted. You also have to consider the charging infrastructure: It is relatively easy and cheap to make 400VDC compared to 800VDC. That a max charge peak is a hyped nonsense figure is clear also , what counts is how many kilometers you can charge in what time in the SOC window of 10%-80%. And finally: While you fast charge you go away and do something like having a meal or do some shopping. That takes 30-50 minutes, which means when the charging is 20mins only you have to interrupt your activity and move the car which is very annoying.
The main point of using 800V is fast charging. By cutting the charging current in half, it allows twice as much power to be pumped though the already unwieldy charging cable and connector.. When fast charging at high powers, even though those cables dissipate only a small fraction of the total charging power, it's still enough that they must have liquid cooling channels in the cable itself. The way to get 350 kW charging without overheating the cable and connector pins is 800V. What I would argue, though, is what car needs 350 kW? I can't imagine needing more that 150 kW. I took a fairly pleasant 1700 mile road trip in my 2022 Nissan LEAF whose Chademo charging was generally 50 kW or less, depending on state-of-charge and battery temperature.
For daily level 2 charging, 800V doesn't make much difference. Fast charging is hard on the battery pack, 350 kW is going to be harder than 150 kW. So most EV charging should be L1 or L2. From my perspective, this insane race attempting to make EVs something they are not is counterproductive. Extremely high charge rates should be reserved for commercial vehicles with battery packs which are larger capacity than those used in cars.
To get some perspective on cable size, take a look at the service entrance cable on your house. Many houses today have 200A service at 240V, which is good for 48 kW intermittently, 38.4 kW continuous. At 400V, 350 kW charging rate would require a cable and connectors rated at least 875A, more than 4X the current of normal whole-house residential electric service. I believe they are trying to keep the cable and connectors below 500A rating. A 500A cable and connector is a beast!
It depends where you are. In North America, it max more sense because nearly every >100 kW charger is already 800 V. Also, 800 V makes far more sense for larger batteries, like the new Ultium 200 kWh packs. The Taycan's battery is limited to about 350 A, so for it, it is limited. However, if you were to cut the voltage in half, the battery wouldn't charge as quickly as it could otherwise because the chargers couldn't provide 700 A.
Right now, I do think GM is the only one doing it properly, where they are including a switch in their 800 V pack, so it can either charge at 350 V or 700 V. In either configuration, it can accept 500 A, so when a 200 kWh Ultium EV is using a 350 kW charger, it should be able to charge at a true 350 kW (~700 V @ ~500 A). The problem in the United States right now is that it appears that Electrify America is limiting most of their 350 kW chargers to 350 A, which is fine for Porsche and VW, but not many of the newer EVs that are pulling >350 A at either 400 V or 800 V.
Outside the Tesla world, I think 800 V has become an option because CharIn chose to limit CCS 2.0 to 500 A in order to support cheaper/longer/lighter charging cables, and they chose to increase max. voltage to 1000 V for additional power. This is a fair enough thought, but in reality, Supercharger V3 has lighter (if shorter) cables and seems the overall more cost effective system. SomI agree with Bjørn that today 800 V based cars really don‘t have much benefits other than in conjunction with the HPC infrastructure that is limited to 500 A.
Agree, 2019 model 3 is achieving 250kw till 25%. And the new 2022 model 3 performance Bjorn testes last week pulled 250kw till 40%> You don't need 800 volts for that at all.
Maybe, internal cabling can be lighter due to lower current. Saving some weight.
Has nothing to do with charging speed at all. That's just a marketing spin.
@@Astke As Bjorn said, the battery packs use the same cells. They are just organized different, a 400volt pack has more cells wired parallel than a 800 volt pack. The charging curve is determined to what the car manufacturer is willing to allow. Some (like Porsche) allow for a very high speed knowing it will hurt the battery and give the owner the possibility to set a max rate at 200kw/h.
The max charging rate a manufacturer is willing to allow is based on cooling capacity and battery chemistry, these are the deciding factors (and how much warranty a manufacturer dares to give). It has nothing to do with 400 or 800 volt delivery.
@@Astke true... Still, the Model 3 remains the quickest on a 1000km challenge... And every Supercharger has 3 to 6 times slots per charging station. So the question is : is it really beneficial for a Porsche / Kia user as they do not travel faster, they have MUCH less charging slots available because of the cos tof hardware and when they do go on 400C station, they cap at 150kW with quite some charging loss?
@@Astke I am coming from a S 75D with much less range and more range is definitely a huge plus. Especially when you are limited at 300km+ highway range (when you have 400 or more, there is diminishing return).
Since when do you have the feeling you can charge on Tesla SC with another car? You are not speaking of the 16 remote stations open to others, do you? Make a North Sud travel of France and tell me how many SC you can use today...
It remains very much a huge asset for Tesla owners. Maybe one day all stations will be open but we are very far from it.
Again, this is a great car (the Polestar) but for the limited interior space and the 15-20 to 30% higher consumption, you cannot just say that it does not matter. It is definitely a big minus.
@@Astke you mean the eTron GT by 10°C...that took 20mn more? You do not think that the Model 3 will not match it by 10°C less? I remind you that the eTron is not more spacious (it is less actually), it costs... DOUBLE and has a much bigger battery with 800V architecture. All that for what exactly?
@@Astke the e-Tron GT is an amazing car. No doubt. Did I ever say otherwise.
EQS is great as well. Both beyond my reach, like many.
Oh, and I do not get where you have seen slippery. The 3 Performance pretty much match the Taycan comparable model on circuit (if you do not put ceramic break on the Taycan). You seem to be the fanboy here.
That is a different package for sure. I am coming from an Audi so the e-Tron almost feels at home for me... Those legacy interior are just... too much (too many buttons, trims, things here and there,..) while being too little (slow infotainment, complicated UI,...) but yeah, Taycan / e-Tron GT are awesome cars, no doubt.
You just can't beat content like this! ♥
When are you going to retest I5 / EV6 1000Km on warm dry weather. To give to give fair test.
800v it's mainly good for charging over 300kW, so it's good just for trucks and bigger vehicles. For cars doesn't make much difference (other than a much higher buying price). Today it's just marketing. Also the efficiency gain it's very small so that most of the 800v cars overall are actually less efficient than 400v
It's not just super high charging speeds though.
800V is very useful for reducing the size and complexity of cables needed for the charger. A 120kW charger would need an expensive water jacketed cable to charge a 400V car at full speed whereas with 800V a much simpler 200A cable can be used.
Quite a few 120kW chargers I've visited with a 100kW+ charging Polestar get stuck at 90kW due to limited current capacity of cable.
@@benjamindesson5326 if the station is rated at 120kw the cable should handle the full 120kw without any problem I don't think the problem was the cable, it could be that the station has a current limit and your battery has low voltage
@@StefanoFinocchiaro It is the cable, 800V vehicles charge fine on it and the spec sheets of the charger show a 200A cable option and a 300/400A cable option. The spec sheet shows that charger can produce more current if the higher current cable is fitted.
800 V can also save some copper in the cars and charge cabels. should also change the 12 V system to 48 V
High 400V cars (peak 450V) are a great sweet spot.
Love technical deep dive videos like this. I guess you can’t even ‘thin out the cables’ on 800V systems because so many established chargers are 400V and you’d be limited to really slow charging speeds. Thanks Bjorn!
An 800 volt motor will have more turns of thinner wire, so though it will run on half the current, it is likely to have twice the resistance, and net, have about the same resistive loss as a 400 volt motor of the same power.
Really, the only gain from an 800 volt system is that you can get more charging power given the 500 amp limit of the charging cable and connectors.
I think a 400/800 V parallel/serial switch would make sense. Rather than a stepup DC/DC converter.
I appreciate that you need to equalize voltage of the two packs before switching to parallel, but I would believe switching to 400V-mode should give less loss than using step-up-converter.
I should be fairly easy to have a Higv-voltag to 12 V convertee that works fine from both 400 and 800 V range.
Splitting the pack introduces more unbalanced parts. Bad idea if you ask me. And you then need extra physical wiring for it. Added weight. Compromise.
@@bjornnyland I think another reason to use DC-DC step up, is that charging station can possibly run at 400 V at 125 A, to get 50 kW, and step it up to whatever the battery is at the moment, even if it is as low as 700 V at 71 A. While dual pack would be 350 V and only charge at 43.8 kW, the step up can possibly charge closer to 50 kW at low SOC too.
I completely agree with you!! Especially about work on efficiency…, and reduce complexity…
Will we see Tesla moving to 800V soon? I don’t think so…
Pretty much every manufacturer is working on 800V systems right now. That isn't done over night though. The reason you don't see 400V Teslas, BMWs, Mercedes is the fact that they aren't done yet. Not that they don't want to.
I expect Tesla to move to 800V soon with their next generation of vehicles. The cybertruck is the first Tesla vehicle that supports 800V charging. I expect Tesla to follow suit on the rest of their line up only when car refreshes occur. It makes little sense for Tesla to not move to 800V architecture when they can reduce the weight of the HV charging cables in the system and reduce the heat losses in 800V architecture. The challenge of course is still supply chain availability which is growing as more and more legacy auto makers are making EVs with 800V architecture.
Keep in mind that what Bjorn is saying its not making much of a difference now because when you charge at Tesla superchargers the 800V capable cars have to derate to 400V charging to be compatible to charge with Tesla superchargers to be compatible with the majority of Tesla fleet and many existing EVs so of course its not charging any faster than the 400V cars. However the Tesla v4 supercharger will be 800V charging capable so I can see the signs of Tesla moving towards 800V charging architecture and will support both 400V and 800V vehicles just like how Tesla is going to move from 12V to 48V LV architecture.
@@erichchan3 yes, I guess you are right. But so many Superchargers are 400V only.., are V4s 800V capable? If not done properly, some 800V cars with the conversion charge quite poorly on 400V chargers (Taycan, for example)… so will they then upgrade thousands of 400V superchargers? Not sure it will happen that soon but I may be wrong… maybe that’s why new model Y maybe delayed a bit as trying to do more than done with model 3?
@@ericvet8b Yes Tesla V4 superchargers are capable of supporting up to 1000V. You do know the Cybertruck is 800V capable right so I see Tesla moving in that direction. Of course the majority of cars are still 400V capable because there wasn't enough supply chain to warrant it. Tesla itself is not enough to warrant the suppliers to build just 800V products. But clearly there are now multiple car manufacturers moving to 800V architecture so I expect Tesla to follow suit going forward.
@@ericvet8b I am not sure if you heard what Bjorn said at 16:50 to 17:40 but he said the fault of the Taycan lies within the converters that Porsche decided to go with. He did say that the Ioniq 5 and other cars have no problem hitting the same power as like a 400V vehicle. Also since Bjorn lives in EU he doesn't know that Electrify America charging stations supports 800V no issue.
Also Tesla V4 superchargers are capable of supporting up to 615 kw (up to 1000V and up to 615A). I don't expect Tesla to push its v4 superchargers to that upper limit but its good to know the hardware is capable of supporting it. Currently the v4 superchargers deployed all have v3 power cabinets so the full v4 supercharger buildout has not been realized yet. Again Tesla has produced a 800V vehicle in the Cybertruck so I can see Tesla moving towards that direction to 800V just like they are going to move all their vehicles to 48V LV architecture for its cost and weight benefits.
I think charging stations will support both 400V and 800V charging for the foreseeable future. I think the EVSE will key off of the communication pins of the charging cable to determine if they are charging via 400V or 800V.
If battery with 100kWh can 250kW it don't make different if 400V or 800V battery. Battery can 2,5C for example that mean 250Ah@400V with 625A charge current or 125Ah@800V with 312,5A.
Tesla SC can about 670A and this make theoretical 270kW@400V possible. If the battery can 4-5C or has 200kWh capacity and can still 2,5-3C then we need more as 250-270kW and with 400V it isn't possible. Today is 800V pure marketing and don't make sence.
A Great explanation Bjorn explained very well. Bottom line is to make EVs more efficient for a better experience.
I'd love to get your comments on the new Taycan charging curve as it holds 300+kW through 60% and above 200kW through 75%.
Porsche even did away with the Eco charging mode because according to the engineers it wasn't needed.
Why are the fastest/best charging vehicles (Lucid/Porsche/Kia/Hyundai) all 800+V when the science/physics says that shouldn't matter?
EVs are in the same patterns for old computers, there was IBM and PC's. At the moment Tesla like a PC and the old car manufacturers are like old IBM. When we were upgrading PC's there was CPU socket and Northbridge Architecture in the mainboards.
So the future of EV's can likely be Battery-BMS-Distribution architecture, so there can be TESLA comptiable parts such as batteries.
Tesla can provide a extensible architecture like PCiExpress in the computers, so you may change parts according to compatible parts.
Björn - the 800 V chargers will only become more commonplace if there are cars utilizing them. So, we do need to have 800 V cars around and they need to become more popular. I agree with your points on the video, but you could have also discussed why this needs to happen. The hyundai/kia motor inverter based system seems to be a very good design, hope more manufacturers go that way. The worst case scenario is we are stuck with 400-450V based systems for 20 years.
Second point - battery heat tolerance. Arent new batteries coming with much larger surface area in battery cell terminal? This should make it easier to use high currents for individual cells? You did not discuss this. Although granted, such batteries are probably 7-10 years in the future for commercial applications.
Is LFP going to change anything?
Many state of the art axial flux motors perform better at higher voltages (600-800V instead of 400). Their higher performance/weight ratio and efficiency is an additional incentive to use an 800V architecture. Beside you can use a smaller inverter.
But even today, the most efficient cars are Tesla (400 V), classic Ioniq (400 V) and i4 (400 V)...
will tesla cyber truck be 800v? does this mean tesla will need to convert chargers or manufacture new chargers? will they combine chargers, also the tesla truck (lorry)will be 800v or 1000v
They've said they'll build new chargers. They're called "megacharger" and the first ones were installed in January. Details not yet released. (that I've seen)
is 800v potentially a little damaging short term - several chargers seem to use kw headline figures based on 800v. And if most cars are 400v they won't get near that kw rate and can be disappointed?
EV6 and Ioniq 5 can charge at 50 kW already at low state of charge on 125 A restricted cables on 50 kW 400 V fast chargers.
Also practical advantage: there are 150 kW HPC chargers that have 250 A cables, which means you can charge 150 kW with an 800 V car but only 100 kW with a 400 V car.
I don't really know any 400 V chargers with more than 50 kW here in Germany except superchargers. I'm sure there are some but they are super rare. And 50 kW chargers are getting more and more replaced. I think in 2 years already we'll be at 98% 800 V chargers.
It is heat that kills the battery, so it seems cyndrical cells seem to handle high heat such as Tesla uses, verses pouch type that the Tycan has, I would say both would suffer from cell degradation using high DC charging rates.
Planned obsolescence perhaps. No point in spending loads of money for an ev that can't keep itself cool, at least in my opinion.
Pouch cells get rid of heat better than cylindrical. Tesla merely throws extra money at the cooling problem.
It is not the heat loss but the charging rate is higher with 800 volt pack verses 400 volt, have yet to see a 400 volt pack do a 10 to 80 % charge in under 20 minutes
I kind of agree, but does it mean that the 800V cars have a platform that need less change (only remove the 400V features) in the future builds?
And are these platforms better prepared for the future because the brands now already get experience with the 800V system, which is not bad since Hyundai have a lot of other lessons to learn (How to deliver a car within 12 month, how to predict that your EV will be very populair and how to scale up and ship).
Don't hear me wrong, I love the way Tesla is can change a car within 12 months and that even in resource shortage you can get their main car in a couple of months.
800 volt EV makes for the user sense only when charged with 800 volt, as to achive a certain kW only half the amp is needed. For the car maker, its half the cables on the 800volt side to charge and feed the motors. 800 volt has been used in marketing as magic. There is more magic in reducing mecanical friction, as a few 400 volts have achieved
No disadvantage in the korean 800 volt. Neither to the user or the battery celles.
Thank you for making this video. I've searched for your videos before trying to figure out what are the benefits of 800 volt.
Problem with 400v cars is now everyone and their cousin need 500a chargers and in America there are only 1 working electrify America ea charger per 50 miles and even then a lot are current derated due to temperature sensors failing. Look at plugshare in California, only 40 percent of the meager 350 kw stations even work. This is not a problem for tesla because they figured out how to install 8 v3 chargers at the pace EA installs one and deliver huge current to their cars. If chargers for ccs were like that I would agree with Bjorn but the current state of chargers means that a 150 kw station (the norm here) delivers 173 kw to an ev6 (nearly to 80 percent) and that same charger does 130 kw to low voltage cars due to current limits.
incredible! and I only count 10 digits.❤
Fossil fuels are also sun power!
the E-GMP 800v system has no compromise - you get the best of both worlds, if you have an 800v charger then it can go as fast as the battery allows, if you have a 400v then it can take 250kW, which is a very respectable figure, and all this is done without additional hardware as it uses the motor's inverter to boost. You need an inverter regardless.
Quit quoting the Taycan's 800v system it's trash, quote the E-GMP one.
The E-GMP supposedly has quite poor efficiency when converting 400 V to 800 V. I haven't tested this yet.
The sky in this video looks like those fake realestate or fake influencer photos - nice
It makes perfect sense. It will be applyed in the future, but now has no practical leverage.
Valid points..
Maybe they save money from copper, weight and from having to redo the electronics when we all arrive to 800v
Most important point,
stepping up from 230volt to 400volt is easier and cheaper than 230 to 800 this adds a lot of costs to the chargers.
you dont even step up. Because between the 3 Phases you have the correct output after the Transformation. And Higher Voltage in the Battery Pack means also double the internal Resitance when you not double the Power Capcity. I can‘t really belive what Bjørn told that 800V have less charging loss.
@@groepi1972 you have the same loss in a battery (x4 internal resistance, 1/2 the current) and less loss in the cabling - slightly less loss in total.
@@volodumurkalunyak4651 in serial you have the same current. When you have half the current you have also half the power. P=U * I.
@@groepi1972 in serial you already have 2x the power (voltage 2x higher - userfull power 2x higher ). 1/2 the current brings power back to previous value. Cable losses are reduced (maybe down to 1/4 if wires are as thick or down to 1/2 if wires are 1/2 as thick)
@@volodumurkalunyak4651 yes and double of internal Restistance for the battery pack. That means more heat on charging and discharging. The only benfit of higher voltage is that you don‘t need thicker Cabels.
And don‘t forget the Grid have only 400V So you need DCDC Converter for 800 V.
And its also a Problem for some 800 V Cars to charge at 400V. Let us see in a few years. We becomme more current for charging faster at 400V thats will be the future.
On Gernan Autobahn you need high speed charging. But there will be a Tempolimit sooner or later …..
Nice analysis, unfortunately missing key insights like you need a lot less copper in order to create 800v systems.
We are in a phase where the scale of electric cars is exponentially increasing. Like you said, 2% is not a lot of losses, but 2% of all charging everywhere is soooo much... You need to think of the big picture!
What about the 2 % charging loss when charging at 400 V? Did you totally forget about that? And we don't know if it's even 2 % or even higher when charging at 150 kW 400 V.
@@bjornnyland interesting take with the what about-ism.
As an owner of an ioniq 5 I will probably never experience the losses, as ionity network is more than enough for any of the long distance travels.
But since the 2% efficency loss is purely speculation in that case. I suspect this will be the experience for nearly all ioniq 5 owners.
I cant speak for others, but it's a definite calculatable difference to all the teslas losing the 2% always.
I think that a shared architecture and standardization of battery packs are missing in EVs at the moment.
From single to 3 battery packs with a decent cooling systems (400V 150kw) two paralelized sockets may be a solution without frying the chemistry.
Lets say a battery package of 50kW is a standardized and 400V 150kW BMS module with one socket is a standard.
And there can be cars with 50kWh(single pack)/100kWh(w2pack)/150kWh(w 3packs) as an option.
At the moment there is a tons of an option for EV batteries and different architectures which is not sustainable.
u should look at the video by lucid on charging at 800v
Please do summer 1000 km challenge with any E-GMP, ionic 5 ev6 gv60 and check the results, 800 volt is not a gimic
Why are you celebrating Teslas 250 kw charging at the charger in the recent model 3 Performance video and at the same time you say that Porsche roasts its batteries with 270 kw charging?
The Tycan has a bigger batted pack, so if the Tycan roasts its batteries, Tesla will roast its batteries twice as fast? Hope you can follow me.
Other than that very interesting! Thank you!
Tesla only allows 250 kW below 10 % for most cars. Many Model 3/Y can't even hit 250 kW and around 200-220 kW is max. Taycan keeps the 265 kW until 30 %, 250 kW until 50 % and 154 kW until 73 %. But the eco charging option is way slower. Watch this video:
ruclips.net/video/4J-XEFSps4k/видео.html
@@bjornnyland Okay, makes sense. Thank you for the explanation. I watch all your videos 💁🏼♂️
Are you talking about there is little difference in charging time between 400v and 800v chargers at an 800v (or above) station. The Rigian CEO disagrees with you. And so does Inside evs. In their article, Nextmove's tests showed that the Taycan isn't able to charge at the advertised 270 kW rate, however, it's not far off. The publication recorded a peak around 250 kW. Nonetheless, the Taycan proved to charge a bit quicker than Porsche's numbers suggest.
After spending some time collecting charging data from the Taycan, nextmove compared it to Model 3 charging speed tests. In the end, the Taycan added more range per hour than the Model 3 even when the Tesla was charging at a V3 Supercharger. I suspect the shape of the curve is the most important element- but I believe if a Taycan is charging on an 800 charger it will beat the Tesla- or was your point that there are not many 800v chargers.
My understanding is electric motors are more efficient at higher voltages. As far as EVs; the manufacturers can choose whatever architecture they want for each car designed. I'm sure many factors play a role and in certain EV applications, higher may not always be better:)
Sure, but as far as I’m aware all 800V pack cars have 400V motors at the moment.
@@MacGuyver85 Really? I had no idea
@@MacGuyver85 Why?
@@matthewwiemken7293 Looked a bit more into this and it appears at least the Porsche Taycan does have 800V motors. They could still internally be 400V but didn’t find anything that detailed. I know the Hyndai/Kia cars have 400V motors with 800V packs.
@@hypothebai4634 Several reasons; component availability, cost, commonality with previous cars etc.
I think that you are just trying to justify your previous comment about no point of having an 800 V architecture, rather than considering the pro and cons and coming up with a balanced view. I disagree with a lot of what you are saying. With an 800V system you halve the heat losses in the cabling and motor and any other component running at 800V, or you can reduce the weight the components by reducing the amount of copper by half. This means less weight and cost. I have had a Taycan in the UK for 2 years and have never encountered a single 400V charger, so have never had my charging limited to 50kW (i don't have the addition 150kW charging unit fitted), so for me your slow charging comments on a 400V charger are irrelevant.
When are you coming back to Ac service Schia Drop-in? 😄
The Korean 800 V cars can do V2G. So if the power price is high during peek hours in the afternoon the the V2G controller can take energy from the car. Then there is at least 2 benefits: Lower energy bill and less stress on the grid. The grid operator should give you extra cheap transfer bill. So you Bjørn need one V2G car in your new house to demonstrate. Then you are in the same game as Robert Llewellyn. Now You Know!
We don't need V2G and it's actually V2Load what Ioniq 5/EV6 do, they don't have grid capabilities, that is something done via charger as well
@@andrei_dk Hmm. But not all EV is made to give away energy via V2Load. Do you agree? If we have inaf V2G storeage then it can help the grid. Im no expert in V2G controller but the device controll the flow from PV, batterypack, EV battery or the grid. So it is not in the EV.
@@GameOver556 Witch 400 V EV have V2Load so it can use V2G systems?
EV with CHAdeMO plug can do V2Load and than use V2G system. Testing in bigger area in the Nederland. So that may be some Nissan, some Korean EV and the triplets.
But you have 800 volt for faster charging. This is not unnecessary.