pianotuna wrote:
If you really want to know, what happens when a lithium-ion battery gets charged below freezing is that metallic lithium is deposited on the negative (carbon) electrode. Not in a nice way either, it grows in sharp, needle-like structures, that eventually puncture the membrane and short out the battery (leading to a spectacular Rapid Unscheduled Disassembly Event as NASA calls it, involving smoke, extreme heat, and quite possibly flames as well). Lucky for us, this is something the BMS prevents from happening."
So if you have solar--turn it off during storage. I don't like that.
This is the summary from the article:
"To sum up, for long and happy LFP battery life, in order of importance, you should be mindful of the following:
Keep the battery temperature under 45 C (113 f) (under 30C if possible (86 f)) – This is by far the most important!
Keep charge and discharge currents under 0.5C (0.2C preferred)
Keep battery temperature above 0 C (32 f) when discharging if possible – This, and everything below, is nowhere near as important as the first two
Do not cycle below 10% – 15% SOC unless you really need to
Do not float the battery at 100% SOC if possible
Do not charge to 100% SOC if you do not need it"
The above are from https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/
another good page on care and feeding:
https://dakotalithium.com/2021/09/22/how-to-charge-dakota-lithium-and-lifepo4-batteries/
not a good page at all, In LFP the largest cause of dendrite formation is from charging, or rather overcharging.
"Lithium dendrites are metallic microstructures that form on the negative electrode during the charging process. Lithium dendrites are formed when extra lithium ions accumulate on the anode surface and cannot be absorbed into the anode in time."
sorry I like to quote scientific studies instead of sales lititure....
when you look up somthing don't just pick the first thing you see that looks like you thought it would, look at a bunch and sort out the **** from the truth man.
with LFP (eve cells) you will get aproximatly 3500 cycles in you go from 100% to 0% every cycle, after that you will still have 80% of the capacity of the battery that will function just like a 20% smaller battery. if you stay between say 10% and 90% for your limits that will proabably increast to 5000 and if ou retrict it even more and shallow discharge, up to 8000. but this isn't like your SiO2 or a normal battery where after the cycle life is over they go in the garbace. the cycle life of a LFP is that you will get that many cycles before the battery is reduced to 80% of its original capacity. kinda like the lumin drop off of LED lights.
you have countless people here who use LFP batteries telling you your a little off on your stuff but you refuse to believe the people who actualy use them over what a sales person in a store who is trying to sell you something says.. then you campain against LFP like your getting paid from a sio2 manufacture to convince people there better. there not better in so many ways. the only way they are is for charging when at -30 if you don't fell like making it so the batteries are warm which is easy.
