We finally got around to installing battery heaters in the truck battery boxes today. The heaters are a rubber pad that consumes .58 Amps at 120 Volts and produces 70 Watts of power. We tested them first and found they have an internal thermistor that opens the circuit at around 115 degrees and closes it back when the temperature falls to below 100. The pads are very flat and we were able to install eleven of them under our 16 Trojan T-145 batteries. We monitored a pad under a 12 volt battery we have for 6 hours and found that during that time, the electrolyte rose to about 100 degrees. We should have better results when they are in the insulated boxes and all the batteries are grouped together. The process took most of the day and also allowed the new EV 13 team the opportunity to learn how to wire a parallel circuit, crimp wires and check the specific gravity of the cell electrolyte. The install was completed and the heaters work great. It takes quite a while to heat the cells, but it will be a welcome addition when cold weather hits. Kudos to the new team that showed up to perform the work on a teacher workday!
On a side note, we have not had to water the cells for over 6 months because of the Water Miser Vent Caps from Flow Systems. The caps have done an exceptional job and we only had to top off the cell levels slightly, using only a half gallon for 16 cells.