Taking Care of LiPo in Freezing Cold Temps

[bumpyrider]

Winter is here, and it's time to wrap your batteries up warm!

Alledgedly, if you try and charge them in the cold, especially at high rates, or to the highest voltage, under 50F / 10C you can cause damage. You can completely mess up your battery by charging in 31F / -1C temperatures, dont plug in a powerful fast charger under 10C! any confirmations, explanations, and details of this controversy?

What advice do you have for caring for LIPO / LIPO4 batteries in cold and freezing temperatures? do you have good insulation? is it safe for them to go out in subzero temps?

 

[bumpyrider]

it's a shame no one gave me any advice on this because the cold killed my brand new litium battery, at least it was new and ran for 20ah, and then after unwittingly overcharging it due to capacity reduction by cold weather, it has reduced it's output by 20 percent to 16ah, maybe lower i dont know. it cost me about 500 dollars so it's abit of a calamity for me.

the odd thing is that i spent at least 1 hour searching for precautions with cold and lithium polymer, including this post and lots of google searches and forums, and no place warned me that charging in cold can cause serious degredation!!!

 

[liveforphysics]

Its a fairly unknown matter.

I know the HVC point should be lowered by perhaps 0.2V/cell between charging at 0c and charging at 25c, and I know its best to charge when the cells are hot (lowest Ri), but I don't think any of us really understand the long term effects of cold charging.

Are you sure the loss of capacity isn't a balance problem?

Were you balancing actively?

Do you have a way to moniter cell voltage as you discharge?

 

[bumpyrider]

Its a fairly unknown matter.
Are you sure the loss of capacity isn't a balance problem?

Were you balancing actively?

Do you have a way to moniter cell voltage as you discharge?

The loss in AH is accompanied by a voltage reading that dips to about 42, then 38 volts, outputting just 10 amps at the end.

the battery would get there after about 21 ah according the the cycle analyst, and now i think it's somewhere between 15 and 17.

i can only monitor overall voltage, i think all the cells are reduced.

The reduction happened in about 2 weeks, trouble is that the charger tops the cells up at a constant 60 volts, some kind of dodgy chinese bms i dunno, it should be 2 volts lower say 57 58, i must have left it at 60 volts half a dozen degrees above freezing and the next time i did 70km it fell short at 50... i dont know if the battery has just reduced capacity and will still have 1000 cycles, or if it is on it s last legs, and that soon it will be at 13 ah...