Simple version: your need/circumstances are identical to mine.
Heater pads are a waste of time/troublesome on their own.
Minus 30, cheap diesel heater lights up. Warm the space, battery will charge when it decides it's warm enough.
I spent LAST winter proving out the battery heater concept.
It failed, in MY case.
Diesel heater running, the space you n the battery are in warms up.
Maybe get to the charging temp or not??
I have a mini woodstove for cold, cheap diesel heater for chilly days.
Skip the heating pads, get the 200 buck diesel heater.
Best dollar value on my whole cargo trailer build.
