Charging LiFePO4 In Cold conditions

All,

I am beginning to see reports on fakebook of batteries not charging, and even showing BMS temperature errors.
This is not just GivEnergy, its a limitation of the technology.

I have found this article about the technology (Vendor neutral), seems to be quite easy to understand.

https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/

https://dcbattery.tech/charging_your_lithium_battery_below_zero/

0C is the danger number, you risk irreparable damage charging below this, the BMS should disconnect if you try.

TheDragon (GivEnergy)
This has been known for a long time! I would say, a bit silly that installers have pushed for installs outside the house exposed to the elements, the fault should lie with GivEnergy.

So should I insulate my outside battery to try to keep the temp up. Its at about 4'c at the moment, but went down to 1'C last night according to the inverter settings icon on the dashboard and I want to charge from ECO 7 overnight.

Karen Maybe do a web chat with Givenergy during office hours and ask? It seems like a sensible thing to do and if it is, it would be good if they suggested everyone might like to do that. Evidently, in the warmer months, it's probably best to remove the insulation, but at this time of the year, why not? Please post here if you do get a response from them so others can consider.

Aren’t most EV batteries lithium ion? In which case they have been operating way below freezing for years?

anglefire

LiFePo4 (the same as in GE batteries) are relatively new to BEVs.
Also, most modern BEVs have thermal management systems to heat and cool the battery packs. Apples and Oranges.

Tim Hi Tim,

I did ring/email and ask if it was OK for my battery to charge below 0'c. Adam said not to worry cos it would stop charging automatically if the temp got too low. The guy on the phone said the same thing but was kind of vague when I asked about insulating it. He asked someone else and they said to protect it from snow, which wasn't exactly what I meant! Anyway - I think I've sussed it! I reduced the charge rate down to about 1000W and set it to charge over the whole ECO 7 period so that over the coldest bits of the night it would effectively be heating itself. Then I got some of that loft insulation which comes in a plastic/ aluminium cover, stapled 3 lengths together and pushed it round the battery. Then I laid a couple of thin sheets of the insulating material that takeaway firms use to keep your meals warm over the top and watched the battery temp like a hawk. The hottest the battery got (according to the inverter icon battery data was 12'C - it seems to be holding the heat OK as it's now 10'C even though the outside temp is -2'C here. Obviously as soon as we are over this cold spell I'll just take it off and put it back in the loft until next time its needed as it only takes about a minute to put it on/off.

Hi
Traditionally batteries stored of charge is based on temperature. Charging and discharging will in itself create heat.
I have my GE 9.5kWhr in my garage and can this week see temperatures via the BMS of 10 degrees C. What I don't know is whether the capacity of my battery is affected. However, as of yesterday I have wrapped my battery in a red (not that it matters) hot water tank insulation- the red type. Oddly I'm not convinced it's made that much difference to BMS indicated temperatures over the past 24hrs. But maybe it was colder in my garage last night. After charge overnight it was at 22 C, with a minimum of 14 C before charge. Without going mad, I'm not sure what else I would do-perhaps I don't need to do anything and that is why GE are fitting these outside. However, I live in Kent. If I were in the Highlands, a different issue I'd expect.

Roberto What I don't know is whether the capacity of my battery is affected.

yes, capacity will be reduced. There's a post here about temperature & capacity: https://community.givenergy.cloud/d/1336-overnight-charging-battery-in-very-cold-weather

Assumed it would. I'll keep it wrapped in its HW cylinder red coat for now. Only wish I could have the inverter beneath the battery to use that heat to warm it!