Path: ...!weretis.net!feeder8.news.weretis.net!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: "Carlos E.R." Newsgroups: sci.electronics.design Subject: Re: lithium explosion Date: Fri, 12 Apr 2024 13:16:40 +0200 Lines: 56 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: individual.net ZpnyWvkGVm7f05/9miijagT+v/rb5r2ch0FfuCam5jRsR1H48D X-Orig-Path: Telcontar.valinor!not-for-mail Cancel-Lock: sha1:2chjtKsElJCXBVjyji9u9iOM3yY= sha256:T1R4gxC5Ky2G1QQCwiPSiKNpiIz3f3Oey1doAHsY8hQ= User-Agent: Mozilla Thunderbird Content-Language: es-ES, en-CA In-Reply-To: Bytes: 3128 On 2024-04-12 07:19, Bill Sloman wrote: > On 9/04/2024 3:03 am, Jeroen Belleman wrote: >> On 4/8/24 18:35, John Larkin wrote: >>> https://www.bbc.com/news/uk-england-london-68744317 >>> >>> It doesn't look like that one was charging. >>> >>> Lithium battery fires are a big deal in New York too. >>> >>> San Fancisco is swarming with illegal, unlicensed electric scooters, >>> surfboards, wheelie things, bikes, and motorcycles. >> >> As the energy density of batteries goes up, failures will >> become more spectacular. It's not a good idea to store >> both oxidizer and fuel in close proximity in the same >> container. It's a recipe for an explosive. > > Lithium batteries don't explode spontaneously. > > The "explosion" is actually the last stage in a process that starts when > the batteries start self-discharging more rapidly than they should, > which warms them up a little. > > Any properly designed battery management system monitors this > self-heating, with temperature sensors at the core of the battery, and > on it's surface. > > If the battery gets hot enough, the higher temperature can lead to a > higher discharge rate, and at a battery temperature between 130C and > 160C which depends on the battery chemistry, the process can run away > leading to something that looks like an explosion. > > Any properly designed designed battery management system would warn the > user when this were incipient and would start discharging the battery if > it had a safe place to dissipate the stored energy. > > It follows that any lithium battery pack that explodes either didn't > have a properly designed battery management system, or was being looked > after by somebody who ignored the early warnings. > > All this is too complicated for John Larkin to keep in mind - we've > discussed it here often enough that he should know it by now. Or the battery wasn't attended. Battery fires have happened when nobody was near the battery; maybe charging. Here, several cities have prohibited personal electric things with wheels from entering the urban public transport system after a few fires. -- Cheers, Carlos.