LFP Batteries: Are They the Safer Choice for Electric Vehicles?
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- Опубликовано: 10 авг 2023
- In this video, I delve into the safety aspects of LFP (Lithium Iron Phosphate) batteries based on data-driven analysis. Contrary to the manufacturers' claims, our findings suggest that LFP may not be as safe as believed. While it requires a bit more effort to trigger thermal runaway, the outcome is concerning as it emits significantly higher levels of flammable gases. Furthermore, LFP demonstrates increased reactivity once failure occurs.
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Looking at tons of videos of guys drilling and nailing 20+ holes in a lfp on youtube and just tiny bit of smoke..
Looking at guy scratching a NMC and get instants humongus explosion AND turbo jet flamethrower effect..
Listening to guy in this video concluding lfp is juuuuust a tiny marginal tiny bit slightly theoretical safer..
F..amazing conclusion!
for real 😂
How about you reference credit to my video you copied in the description?
Feel free to reach out via email.
😂
I have personally back in 2016 driven 6 inch nails right through many old fully charged lifepo4 pouch batteries when disposing of some old surveying equipment (probably about 120 packs - zippy 4s2p 4.2a cells) and they smoked a lot/hot and swelled as you would expect, but no flames at all. Was considered about the best way to deem them safe for disposal at the time, give them a dead short and keep them shorted forever. If you done that with a lithium-Ion/polymer pack or an 18650/21700 cells you would have had an instant fireball on your hands. The down side of course is LifePo4 weighs a lot more than Ion per kwh.
The issues for firefighters is the smoke that is given off is far more flammable compared to other chemistries. If the gasses are confined to a room or container, it can cause a very energetic event.
@@StacheDTraining i'd love to see actual video examples. so far i've only found vids showing some noxious smoke and it fizzles out and they dispose of the battery.
The probem with simply applying a short is that the BMS protect the cell(s) by disconnecting them. The cells stay charged for a very long time, preserving their ability to cause damage.
@@stirlingschmidt6325 so they basically have to be maliciously vandalized for the full effect? which energy/fuel that's in popular usage today is immune to that sort of handling?
@@stirlingschmidt6325, if you read carefully, he is "giving them a short" by driving a nail through them, bypassing any BMS.
"The gas production of the NCM battery is between 1.814-2.752 L/Ah after normalization, while the gas production of the LFP battery is significantly lower at 0.569 L/Ah." - So while true that there is more % H2, it is still less(or same) gas volume since its 50% of 0.6 vs 28% out of 1.8.
There was also study (by some Fire Department) that LFP heats up by 1.5 Kelvin per kWh.min-1 vs 450K ... so all combined, LFP heat up slower and need higher temperatures to start blasting. There should be many more situations, where LFP smokes bud does not start burning at all in car crash vs NMC.
But once it starts, released heat/energy was same.
Well i would probobly compare that to Wh to get a totally apples for apples comparison. But, yes, you are still right
In overcharge or puncture situations the iron phosphate-oxide bond is stronger than the cobalt-oxide bond such that THERMAL RUNAWAY where the battery continues to increase in temp and where the fire can even become an increased risk, is FAR less likely to happen. I think this is a KEY point you didn't even touch.
And yeah, as I finish this video up, you did not do Lithium Iron Phosphate any justice. You didn't really cover any real technical reasons at all. You're better off looking elsewhere for information.
ruclips.net/video/D8xNjz73p80/видео.html
This isn't a technical review of the chemistry, this is a channel to train firefighters. I do address that LFP is a bit safer (ruclips.net/video/YvQ9NEw76G8/видео.html). There is a misconception that LFP will not go into thermal runaway, that simply is not true. That's what this video addresses. Firefighters respond to unlikely incidents daily. Firefighters need to understand the hazards involved with these types of failures, specifically the amount of flammable gasses that are released.
@@StacheDTraining Look man, I think I get that you're marketing this for fire fighters (based on other material you have uploaded), but a LOT of people who are into solar and other diy are going to come across your video, and you should probably take better care to explain your intended audience and what you're drawing attention to *in* the video.
The simple truth is that Lithium Iron Phosphate is **dramatically** safer than many other lithium battery chemistries, evidence of such I presented in the above linked video on a channel run by a guy who has dedicated quite a bit of his time show casing, reviewing solar and the related bits and pieces *and* runs his own forums, and is a far more established channel than you *and* actually tests the stuff very personally.
Now, if you want to say that in a house that's ALREADY in a roaring fire, that these batteries contain risk to your firefighters who might be watching, then say that. But the video evidence that I linked you to literally has a guy running a drill through a lithium iron phosphate battery with no dramatic explosive reaction, which is WAY better than what I could say about other lithium chemistries.
So to say it's a *little* safer is a dramatic understatement and you'll either need to redo your video (maybe even include the clip of Will Prowse's drill test) or just deal with the backlash in the comments.
@@StacheDTraining well firefighters are not very representative of what is actually out there. by definition a firefighter only shows up when there is an event like fire or smoke. so your data is skewed as far as the likelyhood of a problem with lfp battery vs li ion . more data is needed which is likely impossible to compile . how many lfp systems are out there vs how many fail . same with li ion how many installed vs how many fail.
I have used Lithium Titanate cells in various uses including an EV conversion. The safest Lithium chemistry (longest life, best temp range, most power, most expensive)
I used them in a mobility scooter for peace of mind of the user.
Sodium Ion will be interesting.
Unfortunately, it is cost prohibitive for an OEM to adopt. I do look forward to newer/safer chemistries to go into production.
There is s huge difference if you shorten a lifepo4 vs lithium-Ion/polymer batteris( without a BMS protection). Not saying they are totally safe, but in my books there is a significant difference.
We are comparing different battery technology but to put it into context we should compare these batteries against petrol and diesel fuels, for example we have the burn rate one is twice the rate of the other but if it were compared to petrol we would have a rate we could visualise.
Very interesting. What about off-grid solar backup batteries? I am new to this and just bought a Bluetti solar power storage and an extra add-on battery. In the instructions the company says you can use dry chemical fire extinguishers in case of a fire. but that doesn't seem to be very effective.
Generally your home backup/solar setups will be safer when installed properly. The charge/discharge rates are typically more manageable and they are in a safe location void of vibration/crash concerns. However, if there is an incident/failure involving fire, there is not a fire extinguisher that will be able to extinguish the battery cells.
I would personally go for one with LTO cells if i could afford it. I don´t know the off gasing number of them, but they are less likely to burn than LFP, that in turn is less likely than NCA. They also have the benefit of handling about 3 times more cycles. They have considerably lower internal resistance so they tend to not be as warm when charged and diss-charged. Lowering the risk for thermal runaway. They typically also have a safer runaway profile.
Can a bluetti or ecoflow lifepo4 take hot summer heat travels for campers? You know hot car and rv camping gets!!
I have an Ecoflow. Make sure you respect it, keep it clean, and out of the stage weather. Be sure to keep it out of your path of egress
@@StacheDTraining what is stage weather and egress exactly? Thanks! 👍
I was looking for explanation why sometimes there is fire and sometimes there aren't during fail of lifepo4 and now I know, THANK YOU VERY MUCH
I saw a nail penetration test done on a fully charged sodium cell.......it flat out exploded violently like a fire cracker.
It seems the real issue is the amount of H2 released. So in a smaller area that may not be force ventilated, a hazardous mixture can form.
Appreciate you! Dendrites are the trigger, nearly impossible to detect; well shorting out the anode and cathode and creating a thermal runway detects them. To hedge, I gave up 100% SOC in my LFP Eve 280ah in my RV, its a fools errand. RVs are death traps without LFP. I prefer living and not being burned alive over the need to push cells to their advertised capacity. My BMS is programmed at 80% thereby eliminating compressing cells, top level balance and perhaps fire. 100% or even 90% SOC is not worth the risk. Does 80% max SOC slow dendrite formation, I dont know. More monitoring: I am building an MQ8 based sensor for my battery compartment that will disconnect charging on hydrogen gas detection and sound... Fun fact: the explosions at Fukushima could have been avoiding if the Japanese had installed hygrogen absorbing material in their reactors, like we do here in America. Agree the NEC is woefully behind, my EE guru Mike Holt, draws a blank on all this stuff. Perhaps code should require hydrogren gas monitoring and sufficient hydrogen absorption material to allow adequate time to evacuate, vs, storing the cells in the open inside a living space and pushing 100% soc as some badge of honor (will powers)
How from Lithium Iron and Phosphate reaction you get Hydrogen ???? Can someone explain ?
the lithium in LiPO4 is actually LiH (lithium hydroxide) when combined with water or air moisture is gases off H2 among other things.
thank you for explaining the differences in the flammability quotient of different types of lithium batteries. I have severe reservations about purchasing electric vehicle because of what could happen if the vehicle was in a collision. I think we're only at the tip of the iceberg as far as liability and destructionin these types of vehicles.
Can these lfp battery fires be smothered by completely covering in sand?
Unfortunately, you can't smother a lithium-ion battery fire.
Batteries contain both the fuel and oxidizer. Once they get hot enough to ignite, the only ways to put them out is to either quench them (remove the ignition heat) or let them burn. If you successfully quench them, there is still a chance they have enough leftover energy to heat up and re-ignite later. A damaged battery pack isn't safe until it has either been discharged below the amount of energy capable of re-igniting it or destroyed.
We're likely going to end up with the standard EV battery fire procedure being to let vehicles sit in a water container for a week or two to let battery cells corrode and discharge submerged in water before salvaging whatever may be left.
@@StacheDTraining I guess you have not seen the video I think it was out of the Denver area where they wrapped up a car to seal it up and take away. I think you need more training than what you have in order to be discussing the subject.
@@xy4653 ruclips.net/video/3XHB68BqLF4/видео.html
WE NEED BETTER BATTERY TECH
What about LTO batteries. Those are the ones that I think have the best specifications.
Low energy density and high cost. Very unlikely to see it in automotive.
@@StacheDTraining I believe the hybrid McLaren has an LTO pack.
What about energy density? Is LFP equal to lithium? Or, are EV owners trading off range for a modicum of increased safety?
LFP has less range but increased saftey, longevity, and better price.
@@ledzeppelin1212 You're right on the longevity and safety but not on price. Lithium batteries for the same power are smaller and cost less to produce. Around 20-25% cheaper.
Don't forget that good old lead-acid batteries emit hydrogen and oxygen gas, a nearly hypergolic mixture, in ordinary use.
whenever a lot of energy is placed in a very compact space, using highly reactive chemicals.........physical deterioration from wear and tear of cycling, combined with minute manufacturing defects leads to ticking time bomb whatever the chemistry. The emission of flammable gasses during a battery failure sets up the scenario in any kind of confined,indoor or calm area for an eruption of flame that sets a building or structure on fire.
I think you did a good job pointing out the tradeoff with LFP chemistry vs NMC or LCA. However, I don't know if "less fires and more explosions" is a real safety bonus and longer ignition times increases toxic exposure to vapors that can include HF and HCN per testing the UK (see Prof. Christensen's stuff) and other white papers because people might be more likely to get close to it not perceiving the danger(s). I am also wondering about the LEL/UEL of LFP vapors vs the other chemistries. The main fire/explosion problem for the current chemistries will always be the thermodynamic instability and the use of carbonate solvents which are an ignitable liquid. There is so much we don't know about these! Good stuff and keep spreading the word!
The number of people who do not understand 'safer' does NOT mean 'safe' is TOO DAMN HIGH!!!! Even if a LiFePO4 is 'safer' than a Li-(cobalt or....whatever other chemistry), IF it ignites, its still a metal fire. A lithium metal fire. Its the lithium metal fire that is dangerous. And, honestly, the metric by which one determines if a battery is safer than another is important. Put a wrench across the terminals of any high capacity battery and you're going to have an interesting day....
Want safer batteries? Then tell manufactures you are okay with your next device not being a super thin iPhone knock off, and you're fine with a little bit of a thicker body depth, that you dont mind charging it during the day since there actually are so many opportunities to do so around us all the time (in fact standardizing on the USB C plug means everyone's cord will fit every charger and device). Less energy in the same volume is inherently safer. Period. But as long as yall want all the power in none of the space, then the plain and simple truth is too much energy in too small of a volume gets real energetic real quick. The more energy and/or the smaller the volume its in, the less stable it is, the more likely itll go off big time style-y. These are immutable facts of the universe, this is how physics works. Youd think with the STEM and pro-nerd/"yeah science" movement more people would realize that.....Guess they were just going with the zeitgeist to fit in instead of actually learning something.....
this is about storage batteries not cellphone laptop batteries. different chemistry and totally different application. lifepo batteries should last up to 20 yrs . no cell phone battery can last even 5 yrs.
@@ronblack7870 well i have cell phone and other lithiums that are far older than 5 years, so.....
I also have an s5 that crews through batteries, so ......
And what does longevity have to do with the more capacity you cram into a smaller volume the greater potential energy available to be released within a possibly worryingly short period of time?
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They will explode when exposed to electromagnetic pulses originating from nearby seismic events.
some people think these batteries dont have fire issues but that's just not true and can lead to a false sense of security.
lithium is Hazard Class: 4.3 metal and can self ignite in air.
Lithium Iron ignites on contact with oxygen, Lithium Iron Phosphate doesn't.
No cobalt in the LFP batteries, saves money and does not cause a humanitarian crisis.
Like yes, but also "Only around 2% of the world's cobalt is from direct cobalt mining. Most cobalt is a byproduct of mining for nickel and copper too"
@@MrVolodus just like silver. Where cobalt is a by product.
@@MrVolodus True. Even of the direct mining, it is estimated that 15% of the global cobalt supply is from artisanal mining, and that about 15% of that artisanal mining may be ethically encumbered, which means that only around 2% of the supply is ethically encumbered to start with.
Of course, that is an extremely difficult case to make, because your opponent will likely tell you that your moral compass is off if you are okay with even 2%. What I usually do is point out that, all things being equal, that means about 2% of the battery in the device my interlocutor is using to yell at me has the same problem, thereby causing his argument to prove too much, that battery makers actively try to avoid these sources, which should make it much less than 2% in batteries, and finally, that cobalt is used for other things as well (albeit in smaller amounts), such as taking sulphur out of fuel.
But such arguments aside, it is very interesting how such a small problem, and one that is arguably easy to rectify (just refuse to buy that cobalt) can make such a strong emotive argument.
@@plonkster or use a cheaper LFP battery that does not burn and can be charged to 100% everyday.
@@fredfrond6148 I think that is what the video was about (though it has now been many days since I watched it), that LFP does burn if you give it enough heat. It takes more heat before it gets there, but once it does, you have a lithium metal fire just like the other cases. That means the battery is significantly safer, but it very much still does burn if you get it hot enough to melt those separators between the plates. It also off-gasses Hydrogen, so there is a risk of explosion if the gas is not vented.
Don't get me wrong, I love LFP, I have such batteries INSIDE my house for backup purposes. But we should not be blind to the remaining risks.
That is not correct, Lithium-ion batteries typically contain both lithium-ion as well as metallic lithium.
That LFP batteries are no different from other batteries is also not quite true. Firstly they have a very typically charging curve, and have 3.2V nominal voltage. But more importantly is that they are almost inert when discharged that is not true for say NCA cells.
Given that LTO cells are even safer, and really is what should be used as stationary batteries. (still i´m not suggesting LTO are safe, just that they are safer)
No. Once hot they decompose and burn.
Great Video - LFP batteries might be "safer" but they're still not safe enough for electric vehicle use.
Oh? Well keep on driving with NMC then lol
Definately I will have a better chance with LFP. It doesn't matter if the explotion at the end is bigger. That it is unlike that happend. The important it is not burning in low temperatures.
I've got LFP in my Tesla. I feel significantly safer than I would with an NMC battery.