I have a few small solar sytems for off grid projects. My batteries have low temp protection, but if its too cold for too long, the batteries refuse to charge lets them run down. I'd rather not waste power heating the batteries through the night or if its overcast and can't charge anyway.
So here's my thought:
Connect a thermostat controlled heating element to a low voltage cutoff, set to shut off at any voltage below charging voltage. 14v or so.
The heating element is the only thing on this low voltage cutoff.
So, when the sun comes out and the charge controller tries to charge, power kicks on to the thermostat. If the temp is below the set temperature, the heating element comes on. Within an hour or so the battery warms and starts accepting charge for the rest of the day.
Has anyone done this? How did it work?
So here's my thought:
Connect a thermostat controlled heating element to a low voltage cutoff, set to shut off at any voltage below charging voltage. 14v or so.
The heating element is the only thing on this low voltage cutoff.
So, when the sun comes out and the charge controller tries to charge, power kicks on to the thermostat. If the temp is below the set temperature, the heating element comes on. Within an hour or so the battery warms and starts accepting charge for the rest of the day.
Has anyone done this? How did it work?
