Nice explanation and great video!! I have to agree with you on the LiPo safety thing. LiPo battery should never be abused even slightly outside its specs. I have tried this on a LiPo cell pack from a RC car and also from a 2011 MacBook Pro battery pack. In both the scenarios if you were to draw a higher current even for a short duration more than the recommended value you can see the packs start to puff up. 18650 cells as you mentioned are much more tolerant.
One thing worth trying on dead cells ( < 1v etc. ) that don't even start a charger, a conditioning charge. This is from battery data sheets. A small current, about 50 ma for a 18650 cell, can be applied to bring the voltage back up to 3 volts. If they don't get to 2 volts or so after 15 minutes I reject them. After that they will often take a full charge and check out fine. I do like to cycle them and record the storage capacity after, then set them aside, fully charged, and check them for self discharge after a few weeks. Those and any that get overly hot while charging and / or fail to get to a full charge at 500 ma in 8 hours go into the recycle box. A few will be low capacity (
The phone and laptop battery-cells don't discharge at the same rate. The design in itself is destructive for the lifespan. they wire the cells in such a way they can use different voltages for different components. lets take 3 batteries in series. A-B-C from batery A they will take 3.3v from batteries A+B they will take 5v From all three batteries, A+B+C they will take 12v Those are the 3 common voltages most computerized devices will use. Yes I know the actuall batteries aren't rated in those voltages, but it doesn't take much to correct them. When a battery for your device has more than 3 pins/connections,(so 4+) it's almost a guarantee internally they are wired like that. I say almost cuz some designs have the sensors built into the pack aswell. That problem disapears ie with powertools, they just need 1 constant power and change the current for different speeds. And the proof is in the puddin'. We're not seeing these huge amounts of powertool battery packs at recyclers.
Li-ion storage charge is probably around 50% not 100%, li-ions sadly don't like to be kept at 100% all the time either, PB is the one that MUST be kept at 100% and also goes kaput very fast if left with low voltage\charge...
I've had similar experiences with some 18650 cells from laptop batteries. Very low voltages on some (under 2v) and when I put them in the tester, it doesn't even recognize the cell. I have a few "dumb" chargers that will just throw a current on the cells. I put them in there for a bit to get the voltage above 3v, and then transfer them to the tester for a full test..... and many of them check out fine. +2ah and the correct voltage range.
My first new Dell laptop, I left the battery in it all the time, even when I ran it on the power brick... the battery stopped working before it was a year old. My latest new Dell laptop... I only put the battery in the laptop if I am using it or when it's getting charged, when it's full I remove it again. I'd have this laptop with the original battery for ~2.5 years and the battery still lasts 2+ hours.
Jehu, I've always enjoyed your videos, particularly the eSamba project. I am so glad you're doing this series. I was one of those trying to figure out how to harvest these cells and finish with a quality pack at the end. Thanks!
The most common mode of failure that I have found especially in power tool packs is when a battery is run low and then left to sit for an extended time. From that point the cells naturally lose more charge from sitting and fall below the minimum voltage the BMS wants to see, and it will no longer allow a charge. I see this a lot with packs that are discharged from power tools And then left on the shelf and the ambient temperature falls when winter comes which causes the voltage to drop rapidly and the same issue occurs. BMS sees too low pack voltage and deems it bad and won't charge it.
Honestly, liability ha a big part to play in why laptop batteries will stop working rather than corporate greed. Usually you will find one cell that drastically under performs which risk putting strain on the cells in parallel and risks overheating which older chemistries do not like at all. There are a lot of things that are approached from a risk management aspect that drives up cost and reduces longevity, there is a reason a DIY powerwall without UL certification (which includes compliance with IEEE harmonics requirements) and corporate liability insurance behind it if it fails costs a lot less.
when you make the really big Tesla wall battery packs that you did before with hundreds of those batteries did you design a system to identify which individual cell might be damaged or in need of replacement so that you can replace it if necessary?
if one cell fail, all other parallel cells fail too. except you make 1P Packs and connect them in parallel at the very end, but then you need a balancer for each pack.
i stopped harvesting laptop packs since i started looking for the most capacity density, which is important on eletric bikes/vehicles. i ordered bunch of NCR18650B panasonic cells from a chinese seller for like 2.90 EUR each (ordered 1..3 before to see if its genuine), about the same what you pay when buying a tesla module and taking it apart. but prices went off like a rocket after some people found it too.
Glad you did this Jehu. It’s also refreshing and a shared interest that you are paying attention to the feedback. Great explanation. Thanks for sharing.
As I work in PC and laptop repair. Many manufacturers build failure point into the system. Like fuses in weird places etc... And most people do just replace the system/motherboard and BATTERIES.
I'm turning away any "refurbished" laptop packs (sure, I'll still peek in them if I can) because they almost always have crap cells. I pulled apart 3 identical refurb HP packs and yielded 3 completely different brands and capacities of batteries. One set of cells is 100% unmarked! I pulled apart 5 other genuine packs and surprise surprise, all identical Sony cells. The refurb packs always failed in short order when we deployed them. It got so expensive to replace batteries that we just replaced the laptops. Yeah, the cost was that high.
too late to say that but, Garcia, i have an RC and by my experience of LiPo is it last maximum 1 year (using the recommended discharge rate and maximum 2 cycles per week) my RC is a E-revo VXL and the controller is rated at 50A motor, (assuming is as current draw of the RC) and the batt is a nanotech (TRA2820) 2S 2200 mAh 80C burst and 40C continuous, and 50A is way below the 88A discharge rate... and yet they fail relativelly quickly :( and... you also need to consider, 18650 live inside a metal case, while LiPo inside a... plastic baloon? oh, and i recently see about the 18650 have CID`s (current interruption device), what -interrupt the current- when the internal pressure get too high. the pressure opens a little conection inside the battery, an this is why some of them is like a open circuit.
Looking back as I've tried to make use out of older batteries, I've found that it gets complicated on the question of cycle lifetime of batteries and how much is conspiracy. There is no perfect battery; even brand new best quality consumes more power from a charge than it returns. Degrading after x cycles (might say 4000 for LiFePO4 and 400 for Lead-Acid) is of course not a matter of "suddenly it's useless", so I tend to do two things: Use more than the rated cycles even though it lost much of the cell's capacity (maybe use in another device needing lower power), and learning what companies do to force them to degrade faster. For example, if you NEVER charge your smartphone over 80% nor drain below 40% then you'll get wonderfully increased life. Limit 60% even better. Still wears out eventually of course. I forget to stop charging, and ruin them within just a few overnighters @100%. I immediately notice the drastic loss, suddenly fails to last all day, but why is it so hard to get hardware which protects cells? Bingo, they want more money. Why help you keep cells longer? Why help ppl save the good cells when only one cell is bad in a pack? They would make millions less even though it would only cost relatively nothing to solve. I have a msi "gaming" laptop with the feature so someone was aware of the need. Another trick is "hey why charge slower when you can heat them up with super-fast chargers and destroy them sooner?"
great videos that lipo was a B grade one that is why it puffed up , but they dangerous and great care must be taken when charging lipos all the lipos for my Quads half have puffed up ,and you get what you pay for .
Never had a big Li-ion failure, its just the usual, either lost capacity or voltage dropping quickly which is annoying, but with lipos all the ones I bought started to balloon even without use and already had a few that started smoking and if I wasnt watching and removing them from the charger right away and throwing them out of the door to the ourside they would probably end up in a big explosion and I was doing a 1C charge which was totally under their specifications...
A puffy LiPo doesn't mean much about its lifespan, it's a build quality issue sometimes. I have squishy LiPos that are >2 years old and fly fine in a 250 or 500 class quad at full capacity. That LiPo could be puffy for a number of reasons. Did you leave it on your desk charged above a storage charge (ie: fully charged) for an extended period of time? Did you leave it discharged (below storage charge) for a time? Did you pull too hard from the pack? ie: can your heli or quad pull more than the pack can provide, or very very close to? There's more, but you've got to look at more than just it being a B grade cell and it being a tiny bit puffy. Also, it's unfair to compare LiPo and Li-Ion. It's like comparing a gasoline to diesel. Li-Ion is the diesel; stable, safe, slow to output its energy but has power over time. LiPo is gasoline; volatile, a little less safe, and extremely fast to output its energy, giving you massive amounts of power in a short period of time.
I got like 50 Lenovo laptop batteries from my it friend. Is it imperative that I test each cell independently. Could I charge and discharge in them in their groups of 3?
Always disassemble the packs completely, to get each cell - it may be that a single cell has taken down the entire battery pack, including any cells that have been in parallel. So you could have 2x good cells and 1x bad cell in parallel, yes they will all show 0V but you can slowly recharge, and recover, the good ones.
I have just got some laptop batteries to recycle, I blamed you and your video's to the better half as she doesn't like all the mess and charging I'm doing LoL, I found some Prismatic Samsung cells They are marked Line 1 77155A611, Line 2 ICP103450s, and Line 3 SAMSUNG SDI, well I've actually over 60 so what advice give for these type of cells I'm sure you and others have come across them but I can't find much info on them, Love the video's and have gained so much knowledge from you and youre video's. Your Samba project got me interested in E Vehicles when I first saw it last year and due to the budget have started with an E-bike love the whole electric vehicle, Solar, battery walls etc and it's actually affected my lifestyle all thanks to a VW bus video.Thanks love and always await your video's
The cells Dran negative to positive inside the battery packs. The cells on the negative side of the battery were out faster than overheat when they get old. If you have a big flash light with 3 or more cells you only have to change the one cell on the end for the flash light to go on.
I thought lipo only puff when you discarge them to fast if you dont exceed their c rating ive had them last for years and the b grade have a high resistance only use them for low amp draw i think like a transmitter i could be wrong im kinda stupid
You are exactly right, someone also commented about that B grade with a 20C (20*5=100A) rated draw is definitely not rated for a helicopter, you will definitely get some puffing and potential flames as it is causing bad chemical reactions making hydrogen gas, plus the heat that it is at WILL send it into thermal runaway.
yes I just heard Asus laptops maybe others have this disabling chip that counts the cycles and cannot be repaired can I be replaced even though you put new batteries in it the chip will defeat you so how do we defeat the chip or replace the chip or reprogram the chip.... what is the difference in 15 r25r where do I purchase good value 18650 batteries
What about if the cells still work, but they get really hot while charging. I don't want them that hot in my new 18650 headlamp. Charging seemed to be the issue but the really bright mode would probably make them hot too. Would they charge cooler in a more advanced li ion charger made for these kinds of cells, or is heat inescapable in old batteries?
hey jehugarcia (Sorry that i do not know your name). my question is if all the laptop battery has the same battery? i mean the same chemistry? so that i can use them together. thanks.
About 80% of the 18650's for my projects have come from laptop pulls. At work they just dumped 8 HP lap top packs, each one has 8 Samsung 2,600 mah 18650's in it. Score :)
thanks over the last few months you have given me some good insight in to the laptop batteries and what I can do with them, I am already running my Vape mod on the Samsung 18650's I have 6 on rotation so I don't draw to much out of each pair. they work well I am currently looking at collecting some more to make a power wall for the summer house, I can then hook an Inverter to them and power my partners sewing machines, Also I will be installing some 12 v motorhome lighting all recharge from 1x 80 watt solar panel and possible if that is not enough a small wind turbine made by me out of a ceiling fan which cost me a total of £30 to make and that was the magnets from china lol. Keep going Jehugarcia enjoy your videos
I am using DELL latitude e6530 it uses cylindrical battery cells of 5000 mah i want to upgrade it to use 20,000mah lithium cell batteries (like the one used in powerbanks) Is it advisable for me to take this approach?
Just pulled my laptop battery apart because it was dying. Checked the voltage of all the cells and they are good (all of them). Like really good, seem pretty new good. So clearly its programmed to reduce battery life after a certain amount of time. Originally I was planning on replacing any failing cells, but now it seems like that wouldnt accomplish anything - am i right? If its controlled by the BMS then no matter what I do it will still behave the same because its reached a certain no. of cycles? Is there any way that you know of to reset the cycle count?
Your lipo was probably puffed because you left it sitting on your desk while charged/discharged. Put them at a 3.8v storage charge + take care of them and lipos will last years.
I'm using salvaged cells and have been testing each cell with an Opus BT - C3100 for capacity. I'm looking to build a 10p14s battary to live in the basket of an e-bike but am wondering how best to build this if I don't have a perfectly matched set of cells. How far off in capacity can each cell group be? I've got everything from 1800 to 2800 mah. Can I have one group of 10 be built from 2000 mah cells and another from 2100? I also picked up a BMS for this build.
If I understand your question (would help if you gave timestamp), in general you want to use cells expected to behave similarly in how fast they charge and discharge. If one cell drains faster in series, it causes imballance so the whole 4-pack doesn't work in a laptop, but maybe 3 are still good. Open up, test with DMM, and eliminate the cell with extra low voltage (usually the bad one). Over time in your new battery pack, you should probably test individual cell voltages again and see if they are getting off-balance. If you get a few which charge/discharge at similar speed, they are worth using together even if they are not as good as other cells. The balancing is important there.
I bought 2 cell usb charger 6000mah and i am planning to upgrade add 2 more batteries at 4000mah each. will this cause a trouble on mobile, batteries and charger module?
For old laptop battery like 7 years (2012 or 2011), will they aged quite badly? like those from thinkpad. Base on laptop softeware reader, they age quite fast
I have a question in using 4 cells in parallel without any protection in a flashlight, would that be safe ? The flashlight has a low voltage protection and the maximum current is below the battery rating .
Hello Is it possible to reconstruct a battery of a laptop with better quality 18650 Cells than that are used by the OEM Manufacturers. eg i have a MSI ge62 6qf with rubbed off LG cells so i cant tell what MAH they are but the battery is designed for 4700-4900mAh. Since i cant buy an OEM battery in my country and it is like impossible to import as a battery will cost 3 times of the said item to import it. So here comes my idea since i have a spot welder in my university and i can buy good quality Panasonic NCR18650B 3400 mAh, can i replace them in the laptop battery What will be the issues and problems related to the battery Construction except being extra careful in spot welding.
you can..but its a skill...firstly check the battery management system (bms) is working fine.you can then disassemble the battery case carefully and separate the bms,thermisters and the battery pack.then chk the battery voltage individually,make a new ncr battery(brand new) pack and assemble the battery to fit it back in the pc,this is all worth only if ur bms is not faulty
Is it possible to reuse a BMS from a laptop battery with a new battery configuration? Like taking 4 laptop batteries, taking their cells and create for example a powerwall with one of those BMS
can you recommend a lithium battery capacity tester that can connect multiple batteries at once, and also be able to save the information from the tester to a computer
We not only live in a capitalist society, but a mixed economy, a corporatist, cronyist, statist society. In purely a capitalist society, people make gain through mutually beneficial exchanges, accruing (capital) reserves necessary to engage in modern industrial productivity utilising (capital) equipment.. Corporations, people forget, are literal constructs of the state. These constructs, allow for the formation of centralised bodies that govern their conduct, which allows for lobbying groups to negotiate on their behalf. Under such circumstances, lobbyists are prone to make deals with the state to exchange liability immunity for manipulations on the market that benefit them personally. In this sense, we live in a limited liability society. People are alleviated from their personal responsibility, not through contracts / agreements with customer choice, but through the state pre-emptively deal making if they do X, Y, Z, then they are off the hook for resulting liabilities. This is how you end up with batteries (that arguably could rupture or catch fire) using their risk as a justification for rearranging (re)purchasing patterns in their favour, effectively siphoning off unjustified gains. There are two ways of making profit, one by benefiting others, and another by rearranging the market in your favour to siphon off gains that otherwise would have went to others. The latter is like changing the pattern on the chess board to win the game, and this is cronyism. Cronyism is only ever possible, when you can form a psuedo-monopoly on the legitimised use of force, something we call government. Although the socialists will say that these effects are a result of "planned obsolescence", they are promoting the very underpinnings of the causes of this phenomenon. Without rearranging the pattern on the chessboard, something only possible because of government powers, planned obsolescence is all but impossible when someone else is willing to make money over offering you a better deal.
+Brady Rose Wow. You really gave us a different look at why and how corporations and governments rearrange the game so that bad products (batteries that blow up, etc.) and stupid things can exist. Thanks.
SyberPrepper Despite a regulatory environment and its advertised intentions, the results should tell us a thing about the inviability of that approach. It's not a matter of rearranging government, or getting the right people or right ideas in. The dysfunction is innate to central planning altogether. We are better off assuming risk and acting accordingly.
A little bit conspiratorial there with the whole "blame capitalism" aspect. The reality is that if an entire parallel cell pack is not charging, the serial total nominal will be too low to operate the laptop. There is no conspiracy here. Even if only one or two cells in a 2 or 3 cell parallel pack have failed early, the pack will continue to operate but the laptop will report that the battery is no longer holding a charge for as long as it was originally designed and to consider getting a new one. And of course if the BMS dies, well, you are hooped and that is just that. The BMS is the single point of failure. I agree that there is likely a better way to make the battery packs so that they can be more readily serviced but this will inevitably add cost and the entire PC market (Which includes laptops and anything Mac) is so incredibly tight on margins and as you have said, mass produced cells have a low rate of premature failure so why bother. Design challenges to a serviceable battery pack would include but not be limited to the fact that a good consistent contact would need to be maintained in the pack and that the BMS would have to be replaceable as well. I should also note that in the instance of salvaging cells from power tool battery packs, those are designed to output a very large current supply and high voltage (compared to laptop packs) and if they have a cell that does not pass muster, it will have a very deleterious effect on the tool use experience. And yes, I have salvaged from both laptop and power tool packs. Most of the time it is the failure of a whole parallel section that takes out the battery or if it is just a capacity issue, then 2 cells, one each in separate parallel sections. I have only encountered one laptop pack that had a dead BMS. All the cells in it were fine. I also have a 7 year old laptop that holds full charge on the original battery pack. As the saying goes... Your Mileage May Vary.
It's not conspiratorial at all. It's a well known fact in the manufacturing industry - it's called planned obsolesce - products are flat out designed to fail after x number of cycles / amount of time. This affects the electronics, auto, and garment industries like a plague. A second related problem is that things are designed to fail and be replaced and not repairable... not just design either, but with straight up false legal statements/threats and such - for example, all "void if removed" warranty stickers, and "only authorized repair facilities" statements are actually illegal; and are just designed to scare a person into not having their item repaired, or having it done at a huge premium by the original manufacturer (ex. smartphones). I personally know professional mechanics that complain about how every modern car borders on being non-repairable and certain systems actually are not repairable at all, example: instead of just bumping out a dent or something, they have to replace an entire part / section. I am a professional engineer, and know many other professional engineers, and "designing to fail" is definitely a thing, across most industries (typically military is 180 degrees opposite from this, and often healthcare too; though they often have extended service / repair / maintenance contracts instead; this is also often true of large industry, as opposed to consumer-facing). I have a friend who is a manufacturing engineer and "designing to fail" or modifying an already competent design to fail after "x" time... that's a core part of his job. Regulations are a huge part of this too - companies lobby that something has to be done for some reason (safety, security, health, noise, etc), with the result specifically designed to make things non-repairable, non-upgradable, and/or creates lock-in - ex. the wifi router radio issue, car controller firmware, various DMCA bs, the firmware/M$ lockin EFI/BIOS on PCs, being illegal to fix or upgrade old car's emissions systems, etc. On the laptop battery issue - cost is often also a factor - they could put in a better BMS / extra leads to do better load balancing (only 9 cells, c'mon), but it would cost pennies more per unit - probably a large amount of $ when manufactured at volume, and would extend the life of the battery by several years - less $45-$135 batteries you need to buy. Other examples: Toyota just "upgraded" the batteries in the 2016 Prius so they will only typically last around 5 years, as opposed to previously being every ~10 years; and it costs ~$10k per pop. But it saved like 10 lbs off the weight of the car! Yay marketing spin! Apple has come out with irreversible iOS (iPhone OS at the time) updates that literally made older products unusable and customers' only recourse was to buy a newer model at full retail price (had it happen to me TWICE, though they've been a bit better recently).
Samsung are used by à Big Germany company BOSCH. They make very good bicycle motor and battery with Samsung 18650 30Q. i have the 30Q on my bike ans i use with very good performance on my drône in 3S 25Amp discharge
Great series! Really glad you're doing these as I'm trying to learn how to build an 18650 cell for an eBike project on a Schwinn Meridian Adult Trike. I've seen a bunch of them here, but they all seem a little different without a whole lot of info on the numbers, which I WANT. So THANK YOU for doing some! Any ideas on a strategy to build say a solid 48V 2 cell pack system? Still watching! Thanks! BTW You're a real smart dude, you speak plainly, give great knowledge, and I enjoy your vids and glad I found ya.....OK....YT group hug! LOL JK bro! Peace!
You know what I could really use some help explaining *and so I'm sure there must be others) is a little bit about BMS systems. That whole topics really complicates these lithium-Ion batteries. Am I understanding correctly that you are not using them, or are you? Is too much emphasis being put on them and maybe they are not as important as we are made to believe? This is the area where I begin to get lost some...
BMS can mean "battery management system" or "battery monitoring system". Think of the management system as circuitry that actively controls the charge and discharge of the cells in a battery pack. It makes sure that one cell or parallel group of cells aren't charged more or discharged less than the others. The monitoring system just provides you with information on the battery cells' status. You will then have to tinker with the pack to fix what you see wrong - eg rebalance cells or replace defective ones. Both typically have a small circuit across each group of parallel cells in the battery pack that connect to a control circuit that analyzes the signals and directs the action to take (in the case of management) or provides the feedback (monitoring) based on battery status. By definition, a management system must include monitoring.
Yes, I should have been more clear, but I thank you for explaining to me what the BMS is. This I understand, I'm thinking I should rephrase and get more specific with my questions: "How important is cell balancing, how critical is it to have similarly matched cells in a battery. Is cell balancing required for a 3.7V multi cell pack ran in parallel? And if not, can you run multiple 3.7V multi cell packs in series to possibly get away from cell balancing (I'm guessing likely not, but I still seek clarification)." This whole department I have big holes in my understanding, I';m assuming there must be others scratching their heads with some of these same questions? Appreciate any shared knowledge on the subject! Cheers.
+Atimatik Army from what I see most persons match the cells by capacity (ampere-hours) to group in parallel. I believe there would be a greater likelihood of causing an individual cell failure because of over charging or discharging if capacities aren't matched in parallel groups. It is also necessary that they have the same nominal voltage and chemistry. So don't mix a ni-mh battery with li-ion in the same parallel group. Charging sequences are specific to the chemistry and voltages of the cells. Naturally it's also easier to do BMS (management) if you keep the battery type in the pack consistent across the parallel groups.
+Atimatik Army balancing is also done to again avoid the issue of over charging and discharging member units of the pack. I think there is a video in the electric samba series that discusses balancing.
hi i don't mean to be rude however the information you are giving out can be done a lot more efficient ( faster) i love the knowledge and passion peace
YEP !!! Some lap top batteries have a Cycle Clock controlling the battery life. Dell is one of them. After so many cycles the battery is rendered DEAD. I've purchased some NEW lap top batteries that were suppose to be rated . Battery was loaded with 1800mAh 18650 batteries NOT 2600 that would be required to meet the advertised 5200mAh stated rating. As loaded with 1800mAh this battery would only produce no more then 3600mAh.
The problem is not capitalism. The problem is greed and greed infects every economic system, especially when governments have more control over resources.
Greed is incentivized under capitalism. Even if the intention from an individual actor is good, their behavior under capitalism is the same outcome as if they were greedy.
Nice explanation and great video!! I have to agree with you on the LiPo safety thing. LiPo battery should never be abused even slightly outside its specs. I have tried this on a LiPo cell pack from a RC car and also from a 2011 MacBook Pro battery pack. In both the scenarios if you were to draw a higher current even for a short duration more than the recommended value you can see the packs start to puff up. 18650 cells as you mentioned are much more tolerant.
One thing worth trying on dead cells ( < 1v etc. ) that don't even start a charger, a conditioning charge. This is from battery data sheets. A small current, about 50 ma for a 18650 cell, can be applied to bring the voltage back up to 3 volts. If they don't get to 2 volts or so after 15 minutes I reject them. After that they will often take a full charge and check out fine. I do like to cycle them and record the storage capacity after, then set them aside, fully charged, and check them for self discharge after a few weeks. Those and any that get overly hot while charging and / or fail to get to a full charge at 500 ma in 8 hours go into the recycle box. A few will be low capacity (
The phone and laptop battery-cells don't discharge at the same rate. The design in itself is destructive for the lifespan.
they wire the cells in such a way they can use different voltages for different components.
lets take 3 batteries in series. A-B-C
from batery A they will take 3.3v
from batteries A+B they will take 5v
From all three batteries, A+B+C they will take 12v
Those are the 3 common voltages most computerized devices will use.
Yes I know the actuall batteries aren't rated in those voltages, but it doesn't take much to correct them.
When a battery for your device has more than 3 pins/connections,(so 4+) it's almost a guarantee internally they are wired like that.
I say almost cuz some designs have the sensors built into the pack aswell.
That problem disapears ie with powertools, they just need 1 constant power and change the current for different speeds. And the proof is in the puddin'. We're not seeing these huge amounts of powertool battery packs at recyclers.
Li-ion storage charge is probably around 50% not 100%, li-ions sadly don't like to be kept at 100% all the time either, PB is the one that MUST be kept at 100% and also goes kaput very fast if left with low voltage\charge...
I've had similar experiences with some 18650 cells from laptop batteries. Very low voltages on some (under 2v) and when I put them in the tester, it doesn't even recognize the cell. I have a few "dumb" chargers that will just throw a current on the cells. I put them in there for a bit to get the voltage above 3v, and then transfer them to the tester for a full test..... and many of them check out fine. +2ah and the correct voltage range.
I know this is an old video but man I enjoy your channel. Found you while looking for ebike info.
My first new Dell laptop, I left the battery in it all the time, even when I ran it on the power brick... the battery stopped working before it was a year old.
My latest new Dell laptop... I only put the battery in the laptop if I am using it or when it's getting charged, when it's full I remove it again. I'd have this laptop with the original battery for ~2.5 years and the battery still lasts 2+ hours.
Jehu, I've always enjoyed your videos, particularly the eSamba project. I am so glad you're doing this series. I was one of those trying to figure out how to harvest these cells and finish with a quality pack at the end. Thanks!
The most common mode of failure that I have found especially in power tool packs is when a battery is run low and then left to sit for an extended time. From that point the cells naturally lose more charge from sitting and fall below the minimum voltage the BMS wants to see, and it will no longer allow a charge. I see this a lot with packs that are discharged from power tools And then left on the shelf and the ambient temperature falls when winter comes which causes the voltage to drop rapidly and the same issue occurs. BMS sees too low pack voltage and deems it bad and won't charge it.
Honestly, liability ha a big part to play in why laptop batteries will stop working rather than corporate greed. Usually you will find one cell that drastically under performs which risk putting strain on the cells in parallel and risks overheating which older chemistries do not like at all. There are a lot of things that are approached from a risk management aspect that drives up cost and reduces longevity, there is a reason a DIY powerwall without UL certification (which includes compliance with IEEE harmonics requirements) and corporate liability insurance behind it if it fails costs a lot less.
when you make the really big Tesla wall battery packs that you did before with hundreds of those batteries did you design a system to identify which individual cell might be damaged or in need of replacement so that you can replace it if necessary?
if one cell fail, all other parallel cells fail too.
except you make 1P Packs and connect them in parallel at the very end, but then you need a balancer for each pack.
A smart bms with Bluetooth will show you exactly which battery is bad
i stopped harvesting laptop packs since i started looking for the most capacity density, which is important on eletric bikes/vehicles.
i ordered bunch of NCR18650B panasonic cells from a chinese seller for like 2.90 EUR each (ordered 1..3 before to see if its genuine), about the same what you pay when buying a tesla module and taking it apart. but prices went off like a rocket after some people found it too.
I try to tell em those old packs resistance high no capacity. Crap
Enjoy your videos I am a huge DYI just wondering what are the safest and longest lasting battery cells to make a batter for a solar generator.
LiFePO4 chemistry cells are ideal for longevity and safety.
Glad you did this Jehu.
It’s also refreshing and a shared interest that you are paying attention to the feedback.
Great explanation.
Thanks for sharing.
OK, just watched your Tesla 18650 Powerwall vid. Got a much better idea now. TY!
Very good work. Will make a battery for my ham radio gear soon. Thank you.
As I work in PC and laptop repair. Many manufacturers build failure point into the system. Like fuses in weird places etc... And most people do just replace the system/motherboard and BATTERIES.
outstanding work -
you might want to use a thick marker to do any drawing or writing - it shows up a lot better on the video.
Video responses work well..
Thanks for this! I've spent a few hours rewatching videos to answer a question I had knowing you covered it at some point.
Hos does the BMS disable a pack, does It contain a switch of some sort?
+mikeberg Yes, main contactor
I'm turning away any "refurbished" laptop packs (sure, I'll still peek in them if I can) because they almost always have crap cells. I pulled apart 3 identical refurb HP packs and yielded 3 completely different brands and capacities of batteries. One set of cells is 100% unmarked! I pulled apart 5 other genuine packs and surprise surprise, all identical Sony cells.
The refurb packs always failed in short order when we deployed them. It got so expensive to replace batteries that we just replaced the laptops. Yeah, the cost was that high.
"programmed to stop working" ~ Programmed Obsolescence
Spot on, the cycle limit is just as bad as printers that count your pages printed and say "no you are past the limit, go buy a new cartridge"
too late to say that but, Garcia, i have an RC and by my experience of LiPo is it last maximum 1 year (using the recommended discharge rate and maximum 2 cycles per week)
my RC is a E-revo VXL and the controller is rated at 50A motor, (assuming is as current draw of the RC)
and the batt is a nanotech (TRA2820) 2S 2200 mAh 80C burst and 40C continuous, and 50A is way below the 88A discharge rate... and yet they fail relativelly quickly :(
and... you also need to consider, 18650 live inside a metal case, while LiPo inside a... plastic baloon? oh, and i recently see about the 18650 have CID`s (current interruption device), what -interrupt the current- when the internal pressure get too high. the pressure opens a little conection inside the battery, an this is why some of them is like a open circuit.
Looking back as I've tried to make use out of older batteries, I've found that it gets complicated on the question of cycle lifetime of batteries and how much is conspiracy. There is no perfect battery; even brand new best quality consumes more power from a charge than it returns. Degrading after x cycles (might say 4000 for LiFePO4 and 400 for Lead-Acid) is of course not a matter of "suddenly it's useless", so I tend to do two things: Use more than the rated cycles even though it lost much of the cell's capacity (maybe use in another device needing lower power), and learning what companies do to force them to degrade faster.
For example, if you NEVER charge your smartphone over 80% nor drain below 40% then you'll get wonderfully increased life. Limit 60% even better. Still wears out eventually of course. I forget to stop charging, and ruin them within just a few overnighters @100%. I immediately notice the drastic loss, suddenly fails to last all day, but why is it so hard to get hardware which protects cells? Bingo, they want more money. Why help you keep cells longer? Why help ppl save the good cells when only one cell is bad in a pack? They would make millions less even though it would only cost relatively nothing to solve. I have a msi "gaming" laptop with the feature so someone was aware of the need. Another trick is "hey why charge slower when you can heat them up with super-fast chargers and destroy them sooner?"
From which year can be a good laptop battery in order to get good cells?
great videos that lipo was a B grade one that is why it puffed up , but they dangerous and great care must be taken when charging lipos all the lipos for my Quads half have puffed up ,and you get what you pay for .
Thanks so much for making these videos; they're all super educational and you make it easy to learn
Hello jehu. I really appreciate your work. What do you know about over unity and free energy. Gracias.
Never had a big Li-ion failure, its just the usual, either lost capacity or voltage dropping quickly which is annoying, but with lipos all the ones I bought started to balloon even without use and already had a few that started smoking and if I wasnt watching and removing them from the charger right away and throwing them out of the door to the ourside they would probably end up in a big explosion and I was doing a 1C charge which was totally under their specifications...
A puffy LiPo doesn't mean much about its lifespan, it's a build quality issue sometimes. I have squishy LiPos that are >2 years old and fly fine in a 250 or 500 class quad at full capacity. That LiPo could be puffy for a number of reasons. Did you leave it on your desk charged above a storage charge (ie: fully charged) for an extended period of time? Did you leave it discharged (below storage charge) for a time? Did you pull too hard from the pack? ie: can your heli or quad pull more than the pack can provide, or very very close to? There's more, but you've got to look at more than just it being a B grade cell and it being a tiny bit puffy.
Also, it's unfair to compare LiPo and Li-Ion. It's like comparing a gasoline to diesel. Li-Ion is the diesel; stable, safe, slow to output its energy but has power over time. LiPo is gasoline; volatile, a little less safe, and extremely fast to output its energy, giving you massive amounts of power in a short period of time.
Thanks for your 'based on real experience' ,down to earth info
I got like 50 Lenovo laptop batteries from my it friend. Is it imperative that I test each cell independently. Could I charge and discharge in them in their groups of 3?
Always disassemble the packs completely, to get each cell - it may be that a single cell has taken down the entire battery pack, including any cells that have been in parallel.
So you could have 2x good cells and 1x bad cell in parallel, yes they will all show 0V but you can slowly recharge, and recover, the good ones.
Great video, Jehu. Looking forward to the rest of them.
That's the best explanation I've ever heard, awesome info!
I have just got some laptop batteries to recycle, I blamed you and your video's to the better half as she doesn't like all the mess and charging I'm doing LoL, I found some Prismatic Samsung cells They are marked Line 1 77155A611, Line 2 ICP103450s, and Line 3 SAMSUNG SDI, well I've actually over 60 so what advice give for these type of cells I'm sure you and others have come across them but I can't find much info on them, Love the video's and have gained so much knowledge from you and youre video's. Your Samba project got me interested in E Vehicles when I first saw it last year and due to the budget have started with an E-bike love the whole electric vehicle, Solar, battery walls etc and it's actually affected my lifestyle all thanks to a VW bus video.Thanks love and always await your video's
Can you do some experiments with super caps as your energy source
The cells Dran negative to positive inside the battery packs. The cells on the negative side of the battery were out faster than overheat when they get old. If you have a big flash light with 3 or more cells you only have to change the one cell on the end for the flash light to go on.
I thought lipo only puff when you discarge them to fast if you dont exceed their c rating ive had them last for years and the b grade have a high resistance only use them for low amp draw i think like a transmitter i could be wrong im kinda stupid
You are exactly right, someone also commented about that B grade with a 20C (20*5=100A) rated draw is definitely not rated for a helicopter, you will definitely get some puffing and potential flames as it is causing bad chemical reactions making hydrogen gas, plus the heat that it is at WILL send it into thermal runaway.
+SuperBrainAK How do you know 100A is not enough to power my small quad? How can you make such a statement without knowing what I'm powering?
+jehugarcia pretty sure any quad draws more than 100 if it can lift a 5Ah pack, what does it draw then? Which ESC and how many?
Really good tips... I may use both videos to reply some comments in my channel =]
yes I just heard Asus laptops maybe others have this disabling chip that counts the cycles and cannot be repaired can I be replaced even though you put new batteries in it the chip will defeat you so how do we defeat the chip or replace the chip or reprogram the chip.... what is the difference in 15 r25r where do I purchase good value 18650 batteries
I wonder if there is a way to reset the counters on these laptop battery boards...
What about if the cells still work, but they get really hot while charging. I don't want them that hot in my new 18650 headlamp. Charging seemed to be the issue but the really bright mode would probably make them hot too. Would they charge cooler in a more advanced li ion charger made for these kinds of cells, or is heat inescapable in old batteries?
hey jehugarcia (Sorry that i do not know your name). my question is if all the laptop battery has the same battery? i mean the same chemistry? so that i can use them together.
thanks.
About 80% of the 18650's for my projects have come from laptop pulls. At work they just dumped 8 HP lap top packs, each one has 8 Samsung 2,600 mah 18650's in it. Score :)
Not cheap ones tho. so yeah, big score.
Unintended ASMR when he tap on the bateries with the pen
OMG.... thank u Jehugarcia for uploading this video... it has solved most of my questions... god bless u !
thanks over the last few months you have given me some good insight in to the laptop batteries and what I can do with them,
I am already running my Vape mod on the Samsung 18650's I have 6 on rotation so I don't draw to much out of each pair. they work well
I am currently looking at collecting some more to make a power wall for the summer house, I can then hook an Inverter to them and power my partners sewing machines, Also I will be installing some 12 v motorhome lighting all recharge from 1x 80 watt solar panel and possible if that is not enough a small wind turbine made by me out of a ceiling fan which cost me a total of £30 to make and that was the magnets from china lol.
Keep going Jehugarcia
enjoy your videos
Hey, tnx for the video. Could you talk more about planned obsolescence? Is there more seemingly broken stuff that could be easily reused/repaired?
I have A 5000 2s lipo and it gets warm while charging is that bad? it still has good internal resistance and capacity.
What is a music on your channel ? It is great ;)
Thanks for the information!
I am using DELL latitude e6530 it uses cylindrical battery cells of 5000 mah i want to upgrade it to use 20,000mah lithium cell batteries (like the one used in powerbanks) Is it advisable for me to take this approach?
I like to source old model laptop batteries. These are never been used 9 and 12 cell packs, for under a dollar a cell, at quantity.
Hey hello, nice video! What is the background tune?
What is the device to test this batteries?
Just pulled my laptop battery apart because it was dying. Checked the voltage of all the cells and they are good (all of them). Like really good, seem pretty new good. So clearly its programmed to reduce battery life after a certain amount of time. Originally I was planning on replacing any failing cells, but now it seems like that wouldnt accomplish anything - am i right? If its controlled by the BMS then no matter what I do it will still behave the same because its reached a certain no. of cycles? Is there any way that you know of to reset the cycle count?
maybe you can try disconnecting it from the battery pack which itself is the power source to the bms system
Your lipo was probably puffed because you left it sitting on your desk while charged/discharged.
Put them at a 3.8v storage charge + take care of them and lipos will last years.
I'm using salvaged cells and have been testing each cell with an Opus BT - C3100 for capacity. I'm looking to build a 10p14s battary to live in the basket of an e-bike but am wondering how best to build this if I don't have a perfectly matched set of cells. How far off in capacity can each cell group be? I've got everything from 1800 to 2800 mah. Can I have one group of 10 be built from 2000 mah cells and another from 2100? I also picked up a BMS for this build.
how to know which powerful sell
Educational,super helpful. Thanks friend.
I'm really interested in your batteries I would like to buy some the 18650
You think there is 4 module and all module voltage are same but but how we understand that one module soc is low??
If I understand your question (would help if you gave timestamp), in general you want to use cells expected to behave similarly in how fast they charge and discharge. If one cell drains faster in series, it causes imballance so the whole 4-pack doesn't work in a laptop, but maybe 3 are still good. Open up, test with DMM, and eliminate the cell with extra low voltage (usually the bad one). Over time in your new battery pack, you should probably test individual cell voltages again and see if they are getting off-balance. If you get a few which charge/discharge at similar speed, they are worth using together even if they are not as good as other cells. The balancing is important there.
Thanks
I bought 2 cell usb charger 6000mah and i am planning to upgrade add 2 more batteries at 4000mah each. will this cause a trouble on mobile, batteries and charger module?
What will be consider a good battery cell? Should 2200mah be the lowest to consider if I wanted to build my own battery pack for my bike.
What is considered a good pice for "dead Laptop Battery"? Where is a good place to look beside ebay?
Pay full price for generic ebay 10$ 20$pack 2$ acell capacity. Perfect 2200 tests 2200
These arent ultrafire the companies cant take the liabilities. Big difference good products AGyee
I wont pay5$apiece
I would like to get in contact with you if possible as I want to build a power wall...
whats the sound track?
For old laptop battery like 7 years (2012 or 2011), will they aged quite badly? like those from thinkpad. Base on laptop softeware reader, they age quite fast
what if I connect the cells without using the bms, i mean directly connect them
+TECHIE MOTORIST yes
jehugarcia thank you buddy, would it not blow the laptop? and how to connect the cells with the terminals? please reply
Great explanation. Thanks
I have a question in using 4 cells in parallel without any protection in a flashlight, would that be safe ? The flashlight has a low voltage protection and the maximum current is below the battery rating .
What about swollen battery of laptop? Could there be any useful cells? Would it be safe at all to open?
Hello
Is it possible to reconstruct a battery of a laptop with better quality 18650 Cells than that are used by the OEM Manufacturers. eg i have a MSI ge62 6qf with rubbed off LG cells so i cant tell what MAH they are but the battery is designed for 4700-4900mAh. Since i cant buy an OEM battery in my country and it is like impossible to import as a battery will cost 3 times of the said item to import it. So here comes my idea since i have a spot welder in my university and i can buy good quality Panasonic NCR18650B 3400 mAh, can i replace them in the laptop battery
What will be the issues and problems related to the battery Construction except being extra careful in spot welding.
you can..but its a skill...firstly check the battery management system (bms) is working fine.you can then disassemble the battery case carefully and separate the bms,thermisters and the battery pack.then chk the battery voltage individually,make a new ncr battery(brand new) pack and assemble the battery to fit it back in the pc,this is all worth only if ur bms is not faulty
Is it possible to reuse a BMS from a laptop battery with a new battery configuration? Like taking 4 laptop batteries, taking their cells and create for example a powerwall with one of those BMS
Only of you are an electronics wizard
So is there anyway to modify bms? And can we add more cell like 9 or more safely?
can you recommend a lithium battery capacity tester that can connect multiple batteries at once, and also be able to save the information from the tester to a computer
those LiPO batteries are very expensive $50 $60 to beat pieces of junk what can we do to correct this.....
how i can recharge battery fast?
awesome explanation thanks very much ..
Hlo sir, I am very confuse about battery cell , which cell better 2 or 3?
Is sanyo 18650 good? (Made in japan)
+Ali0The0King yes
hell yeah
We not only live in a capitalist society, but a mixed economy, a corporatist, cronyist, statist society. In purely a capitalist society, people make gain through mutually beneficial exchanges, accruing (capital) reserves necessary to engage in modern industrial productivity utilising (capital) equipment..
Corporations, people forget, are literal constructs of the state. These constructs, allow for the formation of centralised bodies that govern their conduct, which allows for lobbying groups to negotiate on their behalf. Under such circumstances, lobbyists are prone to make deals with the state to exchange liability immunity for manipulations on the market that benefit them personally.
In this sense, we live in a limited liability society. People are alleviated from their personal responsibility, not through contracts / agreements with customer choice, but through the state pre-emptively deal making if they do X, Y, Z, then they are off the hook for resulting liabilities. This is how you end up with batteries (that arguably could rupture or catch fire) using their risk as a justification for rearranging (re)purchasing patterns in their favour, effectively siphoning off unjustified gains.
There are two ways of making profit, one by benefiting others, and another by rearranging the market in your favour to siphon off gains that otherwise would have went to others. The latter is like changing the pattern on the chess board to win the game, and this is cronyism. Cronyism is only ever possible, when you can form a psuedo-monopoly on the legitimised use of force, something we call government.
Although the socialists will say that these effects are a result of "planned obsolescence", they are promoting the very underpinnings of the causes of this phenomenon. Without rearranging the pattern on the chessboard, something only possible because of government powers, planned obsolescence is all but impossible when someone else is willing to make money over offering you a better deal.
+Brady Rose Wow. You really gave us a different look at why and how corporations and governments rearrange the game so that bad products (batteries that blow up, etc.) and stupid things can exist. Thanks.
SyberPrepper Despite a regulatory environment and its advertised intentions, the results should tell us a thing about the inviability of that approach. It's not a matter of rearranging government, or getting the right people or right ideas in. The dysfunction is innate to central planning altogether. We are better off assuming risk and acting accordingly.
I bet ur on r/laststagecapitalism
Love your videos. Thanks for this one.
A little bit conspiratorial there with the whole "blame capitalism" aspect.
The reality is that if an entire parallel cell pack is not charging, the serial total nominal will be too low to operate the laptop. There is no conspiracy here. Even if only one or two cells in a 2 or 3 cell parallel pack have failed early, the pack will continue to operate but the laptop will report that the battery is no longer holding a charge for as long as it was originally designed and to consider getting a new one.
And of course if the BMS dies, well, you are hooped and that is just that. The BMS is the single point of failure.
I agree that there is likely a better way to make the battery packs so that they can be more readily serviced but this will inevitably add cost and the entire PC market (Which includes laptops and anything Mac) is so incredibly tight on margins and as you have said, mass produced cells have a low rate of premature failure so why bother. Design challenges to a serviceable battery pack would include but not be limited to the fact that a good consistent contact would need to be maintained in the pack and that the BMS would have to be replaceable as well.
I should also note that in the instance of salvaging cells from power tool battery packs, those are designed to output a very large current supply and high voltage (compared to laptop packs) and if they have a cell that does not pass muster, it will have a very deleterious effect on the tool use experience.
And yes, I have salvaged from both laptop and power tool packs. Most of the time it is the failure of a whole parallel section that takes out the battery or if it is just a capacity issue, then 2 cells, one each in separate parallel sections. I have only encountered one laptop pack that had a dead BMS. All the cells in it were fine. I also have a 7 year old laptop that holds full charge on the original battery pack. As the saying goes... Your Mileage May Vary.
It's not conspiratorial at all. It's a well known fact in the manufacturing industry - it's called planned obsolesce - products are flat out designed to fail after x number of cycles / amount of time. This affects the electronics, auto, and garment industries like a plague. A second related problem is that things are designed to fail and be replaced and not repairable... not just design either, but with straight up false legal statements/threats and such - for example, all "void if removed" warranty stickers, and "only authorized repair facilities" statements are actually illegal; and are just designed to scare a person into not having their item repaired, or having it done at a huge premium by the original manufacturer (ex. smartphones).
I personally know professional mechanics that complain about how every modern car borders on being non-repairable and certain systems actually are not repairable at all, example: instead of just bumping out a dent or something, they have to replace an entire part / section. I am a professional engineer, and know many other professional engineers, and "designing to fail" is definitely a thing, across most industries (typically military is 180 degrees opposite from this, and often healthcare too; though they often have extended service / repair / maintenance contracts instead; this is also often true of large industry, as opposed to consumer-facing). I have a friend who is a manufacturing engineer and "designing to fail" or modifying an already competent design to fail after "x" time... that's a core part of his job. Regulations are a huge part of this too - companies lobby that something has to be done for some reason (safety, security, health, noise, etc), with the result specifically designed to make things non-repairable, non-upgradable, and/or creates lock-in - ex. the wifi router radio issue, car controller firmware, various DMCA bs, the firmware/M$ lockin EFI/BIOS on PCs, being illegal to fix or upgrade old car's emissions systems, etc.
On the laptop battery issue - cost is often also a factor - they could put in a better BMS / extra leads to do better load balancing (only 9 cells, c'mon), but it would cost pennies more per unit - probably a large amount of $ when manufactured at volume, and would extend the life of the battery by several years - less $45-$135 batteries you need to buy. Other examples: Toyota just "upgraded" the batteries in the 2016 Prius so they will only typically last around 5 years, as opposed to previously being every ~10 years; and it costs ~$10k per pop. But it saved like 10 lbs off the weight of the car! Yay marketing spin! Apple has come out with irreversible iOS (iPhone OS at the time) updates that literally made older products unusable and customers' only recourse was to buy a newer model at full retail price (had it happen to me TWICE, though they've been a bit better recently).
can I charge 3 batteries in parallel but make it as one battery
Samsung are used by à Big Germany company BOSCH. They make very good bicycle motor and battery with Samsung 18650 30Q.
i have the 30Q on my bike ans i use with very good performance on my drône in 3S 25Amp discharge
But 18650's are Li-Ion right? The once in the teslas are liion..
how make lithium ion batterybank for laptop make it 12 hour working
Great info, as always!
Chalkboard?
this clarified things.
Great series! Really glad you're doing these as I'm trying to learn how to build an 18650 cell for an eBike project on a Schwinn Meridian Adult Trike. I've seen a bunch of them here, but they all seem a little different without a whole lot of info on the numbers, which I WANT. So THANK YOU for doing some! Any ideas on a strategy to build say a solid 48V 2 cell pack system? Still watching! Thanks! BTW You're a real smart dude, you speak plainly, give great knowledge, and I enjoy your vids and glad I found ya.....OK....YT group hug! LOL JK bro! Peace!
Awesome video
You know what I could really use some help explaining *and so I'm sure there must be others) is a little bit about BMS systems. That whole topics really complicates these lithium-Ion batteries. Am I understanding correctly that you are not using them, or are you? Is too much emphasis being put on them and maybe they are not as important as we are made to believe? This is the area where I begin to get lost some...
BMS can mean "battery management system" or "battery monitoring system". Think of the management system as circuitry that actively controls the charge and discharge of the cells in a battery pack. It makes sure that one cell or parallel group of cells aren't charged more or discharged less than the others. The monitoring system just provides you with information on the battery cells' status. You will then have to tinker with the pack to fix what you see wrong - eg rebalance cells or replace defective ones. Both typically have a small circuit across each group of parallel cells in the battery pack that connect to a control circuit that analyzes the signals and directs the action to take (in the case of management) or provides the feedback (monitoring) based on battery status. By definition, a management system must include monitoring.
Yes, I should have been more clear, but I thank you for explaining to me what the BMS is. This I understand, I'm thinking I should rephrase and get more specific with my questions:
"How important is cell balancing, how critical is it to have similarly matched cells in a battery. Is cell balancing required for a 3.7V multi cell pack ran in parallel? And if not, can you run multiple 3.7V multi cell packs in series to possibly get away from cell balancing (I'm guessing likely not, but I still seek clarification)."
This whole department I have big holes in my understanding, I';m assuming there must be others scratching their heads with some of these same questions? Appreciate any shared knowledge on the subject! Cheers.
+Atimatik Army from what I see most persons match the cells by capacity (ampere-hours) to group in parallel. I believe there would be a greater likelihood of causing an individual cell failure because of over charging or discharging if capacities aren't matched in parallel groups. It is also necessary that they have the same nominal voltage and chemistry. So don't mix a ni-mh battery with li-ion in the same parallel group. Charging sequences are specific to the chemistry and voltages of the cells. Naturally it's also easier to do BMS (management) if you keep the battery type in the pack consistent across the parallel groups.
+Atimatik Army balancing is also done to again avoid the issue of over charging and discharging member units of the pack. I think there is a video in the electric samba series that discusses balancing.
Tarquin Joseph Yeah, I'll have to look for it... Kinda like the eSamba master was saying, even he has trouble finding!!
hi i don't mean to be rude however the information you are giving out can be done a lot more efficient ( faster) i love the knowledge and passion
peace
Jehu - what's up with the tremors? Are you shaking your foot when talking in front of the camera??? :-D
+Tony Lorentzen restless legs
Hehe - that's what I thought ;-)
YEP !!!
Some lap top batteries have a Cycle Clock controlling the battery life. Dell is one of them. After so many cycles the battery is rendered DEAD. I've purchased some NEW lap top batteries that were suppose to be rated . Battery was loaded with 1800mAh 18650 batteries NOT 2600 that would be required to meet the advertised 5200mAh stated rating. As loaded with 1800mAh this battery would only produce no more then 3600mAh.
3:02 *COUGH* apple iphones *COUGH*
DotCD 😂😂😂😂
DotCD 8:12 COF COF ANDROIDS COF COF
COUGH Huawei phones COUGH
The problem is not capitalism. The problem is greed and greed infects every economic system, especially when governments have more control over resources.
Greed is incentivized under capitalism. Even if the intention from an individual actor is good, their behavior under capitalism is the same outcome as if they were greedy.
Why does everyone go crazy over 18650 batteries for, it almost borders on obsession.
It’s like candy