Cold weather options for LifePO4 batteries

Itinerant1 wrote:

phemens wrote:
The guy that built my batteries is noodling around with these Link
They're heating pads for pipe elbows, they draw 7.5 watts each, he says I'd need 2x battery, which means 12 total or 90 watts total (6 batteries). He's hooking them up to a 1207 temperature controller. That's what I'm going to try and the controller for the blown air, maybe the pads are a better long term solution. I guess another option would be to stick the larger tank heating pad to a sheet of aluminum to span the footprint of all the batteries.
We'll see!

I entertained this Facon warming padunder the batteries. I would of stuck it to an aluminum sheet cut to fit the wooden structure containing the batteries to spread the heat as best as possible. Wired into the 12v fuse panel but having a toggle switch to give power when needed. The only issue I was worried about is it being sandwiched between the 1/2" rubber pad and the aluminum sheet, then having the batteries sitting on top. I don't know if it would matter?

At 5.6a while running is so little of a draw, which is equal to the humidifier that is always running in the trailer.

I wouldn't stick any of the heating pads directly on batteries incase it quit working so not to have a sticky mess on them.

That's what I was looking at initially, sticking it to an aluminum sheet underneath the batteries but on top of styrofoam insulation. Given the relatively light weight of the LifePO4 batteries I would think the weight on the heating pads would be ok.
I would wire it into a temperature controller then an on/off switch. That will be the permanent solution I think. 5.6 amps is more than fine as long as it can maintain the temperature at about 5C.
I may be building a new set of 280AH battery banks next spring, and one possibility would be to insert the heating elements in between the cells before they are put together.