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I only wish you don't get your flat/home burned up due to faulty battery because of your misconception and that others will ignore it. Again, never, under any

I only wish you don't get your flat/home burned up due to faulty battery because of your misconception and that others will ignore it. Again, never, under any circumstances, try to charge a swollen laptop battery. https://www.howtogeek.com/244846/what-to-do-when-your-phone-or-laptop-has-a-swollen-battery/ https://www.howtogeek.com/244846/what-to-do-when-your-phone-...

jacquesm 6y ago
Thank you, I'm perfectly ok and actually know what I'm doing. Your fears are misplaced. Batteries are - as long as the design is proper and the charge requirements are met - reasonably safe. Given that we have many 100's of billions of them in operation and that there are not that many reports of spontaneous combustion is good proof of that. Dead batteries are murdered, they don't die of their own accord. What kills batteries and may cause them to misbehave: - overheating - overcharging - repeatedly deep discharging - short circuiting - puncturing - deformation of the container - poor enclosure design - shock loads (usually in combination with poorly designed mounts such as wrap around straps on heavy batteries) Other than that you should be perfectly fine. Your concern is appreciated but the misconception is on your end, keep in mind that I do tech DD for a living and I'm quite familiar with the literature regarding battery safety, medical devices and other on the body devices using LiPo and other high density batteries are commonplace now and everybody is trying to work hard to avoid being the next Wakemate. https://www.coolbuster.net/2010/12/wakemate-fire.html https://www.coolbuster.net/2010/12/wakemate-fire.html The examples listed in your linked article are all way past the design limits and obviously there is no point in even attempting to continue to use a battery like that and in fact poses significant risk. But that does not contradict anything I said: high density batteries tend to expand a bit over their design life. If you don't want to accept that that is fine with me, but maybe then you should stop using such batteries altogether. From: https://www.rchelicopterfun.com/puffed-lipo.html https://www.rchelicopterfun.com/puffed-lipo.html "As we just found out, LiPo cells can & will swell. It's actually somewhat normal as they age since electrolyte decomposition is occurring all the time. The speed at which it occurs, and if excess O2 or CO2 is released, is based on many factors including how hard you run (discharge) the packs, how fast you charge them, how you store them, their age, the quality of the packs, and of course how much they heat up during use." Which is a pretty correct summary of the reality of operating such high energy density batteries. Typical battery chemistry involves a step that may produce some gas and this is perfectly normal. Because gas occupies more volume than the solid the gas came out of the battery geometry will change and because the charge/discharge cycle isn't perfect over time you may have a build up of some gas. This is why the battery 'sleeve' is a bit elastic and very strong. In fact, that's the whole reason they puff up in the first place, if the sleeve were porous or had an overpressure vent then the swelling would not happen. Too much swelling is a sign a battery is end-of-life and should be replaced. As a good rule of thumb: if the battery is outside of its designed space or geometric limit then the swelling is excessive, in other words, if it touches stuff that it would not normally touch when it was still new then it should be discarded. If you want to be nice to your batteries: keep the charge/discharge cycle between 95 and 50% or so, ensure they are well ventilated, if there is any sign of overheating stop charging, never ever puncture a high density battery and if you ever drop the gear the battery is in inspect the battery before charging it again. Do not short-circuit or overload a battery, they have super low internal resistance and will be more than happy to outgass so fast if you do that the enclosure may blow up, worst case you will induce thermal runaway with all of the consequences that go with it.
lmilcin 6y ago
@jacquesm: I can't reply to your post, so do it here: Even assuming you do know what you are doing, it is still very irresponsible to tell this to people who will have no way to make use of the knowledge safely. When somebody has their expensive laptop swollen they have incentive to delude themselves it is ok. It is not and it is dangerous. There is no way to tell the reason the battery is swollen and so the thing they should do is to not charge the battery and get it replaced.
- jacquesm 6y ago
  You're fearmongering all over this thread. Stop digging, you are at hobbyist level with your knowledge on a forum with professionals. if you can't tell the difference between 'batteries will swell some during their operating life' vs 'excessive swelling is a sign things are about to go pear shaped' then you shouldn't be working on your own laptop period. Any laptop older than 12 months will have a slightly swollen battery (even if that swelling is accommodated by the case immediately around the battery so you won't see it). HN stands for 'hacker news', if batteries scare you then don't use them. The same goes for powertools, explosives, household cleaning products, chisels, hammers and so on. Danger is a relative thing. Knowing the head fire marshall of a very large (2 million inhabitants) European city: if you are afraid of fire then you should disconnect all your wall-warts. Those are the cause of a very large number of fires and the best way to deal with them is to switch them all off when you leave your home. Batteries are a very distant second to that and stories of them catching fire are rare enough that they make the news. See also: Samsung and Boeing. https://en.wikipedia.org/wiki/Samsung_Galaxy_Note_7#Battery_faults https://en.wikipedia.org/wiki/Samsung_Galaxy_Note_7#Battery_... https://en.wikipedia.org/wiki/Boeing_787_Dreamliner_battery_problems https://en.wikipedia.org/wiki/Boeing_787_Dreamliner_battery_... Note that a perfectly good battery can go into thermal runaway in a couple of seconds if mistreated, the amount of energy these pack is very impressive and if that energy is released quickly then the results can be catastrophic, even resulting in the hull-loss of airliners if the combination of circumstances is particularly bad: https://safetyfirst.airbus.com/lithium-batteries-safe-to-fly/ https://safetyfirst.airbus.com/lithium-batteries-safe-to-fly...
  - lmilcin 6y ago

jacquesm 6y ago

Thank you, I'm perfectly ok and actually know what I'm doing. Your fears are misplaced. Batteries are - as long as the design is proper and the charge requirements are met - reasonably safe. Given that we have many 100's of billions of them in operation and that there are not that many reports of spontaneous combustion is good proof of that. Dead batteries are murdered, they don't die of their own accord. What kills batteries and may cause them to misbehave: - overheating - overcharging - repeatedly deep discharging - short circuiting - puncturing - deformation of the container - poor enclosure design - shock loads (usually in combination with poorly designed mounts such as wrap around straps on heavy batteries) Other than that you should be perfectly fine. Your concern is appreciated but the misconception is on your end, keep in mind that I do tech DD for a living and I'm quite familiar with the literature regarding battery safety, medical devices and other on the body devices using LiPo and other high density batteries are commonplace now and everybody is trying to work hard to avoid being the next Wakemate. https://www.coolbuster.net/2010/12/wakemate-fire.html https://www.coolbuster.net/2010/12/wakemate-fire.html The examples listed in your linked article are all way past the design limits and obviously there is no point in even attempting to continue to use a battery like that and in fact poses significant risk. But that does not contradict anything I said: high density batteries tend to expand a bit over their design life. If you don't want to accept that that is fine with me, but maybe then you should stop using such batteries altogether. From: https://www.rchelicopterfun.com/puffed-lipo.html https://www.rchelicopterfun.com/puffed-lipo.html "As we just found out, LiPo cells can & will swell. It's actually somewhat normal as they age since electrolyte decomposition is occurring all the time. The speed at which it occurs, and if excess O2 or CO2 is released, is based on many factors including how hard you run (discharge) the packs, how fast you charge them, how you store them, their age, the quality of the packs, and of course how much they heat up during use." Which is a pretty correct summary of the reality of operating such high energy density batteries. Typical battery chemistry involves a step that may produce some gas and this is perfectly normal. Because gas occupies more volume than the solid the gas came out of the battery geometry will change and because the charge/discharge cycle isn't perfect over time you may have a build up of some gas. This is why the battery 'sleeve' is a bit elastic and very strong. In fact, that's the whole reason they puff up in the first place, if the sleeve were porous or had an overpressure vent then the swelling would not happen. Too much swelling is a sign a battery is end-of-life and should be replaced. As a good rule of thumb: if the battery is outside of its designed space or geometric limit then the swelling is excessive, in other words, if it touches stuff that it would not normally touch when it was still new then it should be discarded. If you want to be nice to your batteries: keep the charge/discharge cycle between 95 and 50% or so, ensure they are well ventilated, if there is any sign of overheating stop charging, never ever puncture a high density battery and if you ever drop the gear the battery is in inspect the battery before charging it again. Do not short-circuit or overload a battery, they have super low internal resistance and will be more than happy to outgass so fast if you do that the enclosure may blow up, worst case you will induce thermal runaway with all of the consequences that go with it.

lmilcin 6y ago

@jacquesm: I can't reply to your post, so do it here: Even assuming you do know what you are doing, it is still very irresponsible to tell this to people who will have no way to make use of the knowledge safely. When somebody has their expensive laptop swollen they have incentive to delude themselves it is ok. It is not and it is dangerous. There is no way to tell the reason the battery is swollen and so the thing they should do is to not charge the battery and get it replaced.

jacquesm 6y ago
You're fearmongering all over this thread. Stop digging, you are at hobbyist level with your knowledge on a forum with professionals. if you can't tell the difference between 'batteries will swell some during their operating life' vs 'excessive swelling is a sign things are about to go pear shaped' then you shouldn't be working on your own laptop period. Any laptop older than 12 months will have a slightly swollen battery (even if that swelling is accommodated by the case immediately around the battery so you won't see it). HN stands for 'hacker news', if batteries scare you then don't use them. The same goes for powertools, explosives, household cleaning products, chisels, hammers and so on. Danger is a relative thing. Knowing the head fire marshall of a very large (2 million inhabitants) European city: if you are afraid of fire then you should disconnect all your wall-warts. Those are the cause of a very large number of fires and the best way to deal with them is to switch them all off when you leave your home. Batteries are a very distant second to that and stories of them catching fire are rare enough that they make the news. See also: Samsung and Boeing. https://en.wikipedia.org/wiki/Samsung_Galaxy_Note_7#Battery_faults https://en.wikipedia.org/wiki/Samsung_Galaxy_Note_7#Battery_... https://en.wikipedia.org/wiki/Boeing_787_Dreamliner_battery_problems https://en.wikipedia.org/wiki/Boeing_787_Dreamliner_battery_... Note that a perfectly good battery can go into thermal runaway in a couple of seconds if mistreated, the amount of energy these pack is very impressive and if that energy is released quickly then the results can be catastrophic, even resulting in the hull-loss of airliners if the combination of circumstances is particularly bad: https://safetyfirst.airbus.com/lithium-batteries-safe-to-fly/ https://safetyfirst.airbus.com/lithium-batteries-safe-to-fly...
- lmilcin 6y ago