profdant139 wrote:
. . . if I insulate the battery box, and we are camping in 25 degree weather (not that cold), I assume that the internal heater will cycle on and off, keeping the battery at 35 degrees, right?
If that is true, then the 1.8 amp draw from the heater will be fairly minimal, since it is not continual
Correct. True. The BB heating element appears to be very efficient. Not sure insulation is necessary camping at 25f. The ah savings would be minimal. At 0f, the heating element only uses 13.2ah in 24 hours. At 25f, I'd guess-estimate 5-6ah. To give you idea how insignificant that is, your RV, with *everything* turned off, would probably still use 24-36ah (of parasitic current) in 24 hours.
profdant139 wrote:
, if you have the time, could you tell us more about the DIY heater you made? You mentioned that it has a "Switchable control (thermostat or BMS)." Please forgive my ignorance -- what is a BMS?
Do you have a post or a youtube video describing your setup?
No worries. 18 months ago I didn't know what a BMS was either. To answer your question, the BMS (Battery Management System) continually monitors voltage/current/temp of the cells. If it monitors anything that goes below or above preset values, the BMS will immediately turn off charge or discharge current as appropriate---protecting the cells from any potential damage.
As for the "DIY heater", this was not something we installed on an existing OEM lifepo4 battery. It was something we attached to the individual lifepo4 cells as part of a 200ah lifepo4 battery pack we assembled from scratch. If you think you may be interested in building your lifepo4 cell pack, I'd be happy to provide further details.
