Minimum Amps required for Self-Heating LiFePO4 battery?

[Charva]

Just purchased a Li Time Self Heating battery and then received the diagram below that states it requires a charging source above 20A. My panel is 150W (9.3A) connected to a 30 amp PWM controller. Does that mean that even if the panel is getting full sunlight the BMS won't have enough Amps to activate the self-heating pads in the battery? If so, can I use my controller to override the battery BMS? (Having a tough time getting a direct answer from LI-Time.)

 

[12vDC]

The answer is no.
As I understand how self-heating works, the BMS will disengage the charge circuit at 32° until 41°F and then allow charging.

Unless your battery is different, ignore the “20A charger” info with regards to selfheating.

 

[Charva]

I finally got a response from the manufacturer and unfortunately it will not start the heating with a charger under 20 A. Here is their response:
“If the solar charger's charging current is less than 20 amps,
the solar charger will not be able to heat the battery's internal heater to charge the battery,
so it will be difficult for the 12V 200Ah plus self-heating battery's internal temperature to reach 41 degrees Fahrenheit or higher to continue charging the battery.
We recommend that the solar panels have a power of 800 watts or more to make it easier to provide a 20A charging current.”
I wish this information had been available on their battery description as it is a critical piece of info! Hopefully I can exchange it…

 

[12vDC]

Oh wow. Thats why I came here is to learn.

I agree thats not an ideal performance from LiTime.

I believe Redodo Power Queen LiTime are the same. And if so, they are very good about customer service (exchange).
Maybe you could even get a refund?

 

[Charva]

Didn’t know power queen was same. The person Ive been speaking with is in China but it’s shipped from 1 of 3 places in US. I’ve heard good things about customer service so am optimistic about an exchange as the self heating clearly has nothing for me. Would rather pay same ( or less) for a bit more power.

 

[Rednecktek]

240w heaters!!??!! Holy cow!!!

 

[Charva]

Was informed by seller to refuse the shipment face to face with the driver and fed ex will return it and I will get a refund. Otherwise I may have to pay return postage.