DrewE wrote:
How much wattage you'd need would depend a lot on how well you insulate around the batteries. With sufficient insulation, it would not take much power--possibly even none, if the DC electric usage were sufficient--to keep them warm.
Perhaps enclosing the batteries in a cheap cooler would be a decent start. AGM batteries would be an advantage for doing this as they have much less required in the way of ventilation etc.
Thanks Drew, Certainly something to consider and easy to accomplish. I had actually thought about the heat generation during use, but.....got fixated on the “heat pads. Probably should have done the insulation first, then.....