The equations differ but generally degradation formula is: Time x Temperature x SoC(Delta from 50% with an exponent towards the low/high end).
Basically that means you want to do long term storage around 40-60% and if it's hot out, even more important. You definitely don't want a long time of a pack sitting too high or too low, especially when it's hot. LFP is more tolerant, but not immune as some people claim. The worst thing for a pack is letting it sit at 100% in hot weather for a long time. If you must charge to 100%, try to use it as soon as you can, especially in warmer weather. Sadly there are a lot of devices that always charge to 100% everytime you charge, and cannot me changed. This is why most laptops and phones start to show marked degradation after only 2 years, because they sit at 100% for many hours, and are often hot too. If you charge a ternary cell to only 4.0v instead of 4.2v you massively extend it's life. On LFP it's 3.4v vs 3.6v, and it's less of a gain, but still significant! You lose very little capacity at the top end, so it's well worth doing if you can. The same thing occurs at very low cell voltages. You get dendrite growth, so try to avoid the very deep cycles, and if you do, charge ASAP back to the "middle". If you have a pack used for backup, such as a UPS, then definitely important to build more base capacity and only charge to ~80% max if you want it to last you a really long time. On Fri, Mar 13, 2026 at 11:42 AM redscooter via EV <[email protected]> wrote: > if a battery sits at a very low SOC is the same "damage" done weather > it sits for 5 minutes or 5 days? > > talking lion or lfp . should I go charge it soon as possible? like if > I'm runing the weed eater, stop n charge right when it runs low. > _______________________________________________ > Address messages to [email protected] > No other addresses in TO and CC fields > HELP: http://www.evdl.org/help/ > OT: If you use an Android device, please read https://keepandroidopen.org/ > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20260313/362d0d8c/attachment.htm> _______________________________________________ Address messages to [email protected] No other addresses in TO and CC fields HELP: http://www.evdl.org/help/ OT: If you use an Android device, please read https://keepandroidopen.org/
