I have 2 -fairly new100Ah Wattcycle batteries. They are in a marginally heated compartment; right now the battery temp is -3*C.
I just did a drawdown test, and the batteries dropped to 12.3 V as soon as I turned off the charger, and then my battery shutoff kicked in at 12V. All this time the draw was 9-10 amps.
This freaks me out a bit as I really need my batteries in cold weather.
Did I toast my batteries by charging at low temps?
Is there a low temp charge protection in the BMS?
Anything else I should be doing for cold weather performance?
Is it possible that the cold weather charge protection is kicking in and the batteries simply aren't charged? In which case my 12V automatic disconnect would be awesome. But how do I get those batteries to charge????? Hmmmmm.....
I use mine in ice conditions in the Lower Niagara River (as trolling motor and electronics batteries) after converting from flooded / AGM batteries). It's the temperature.
I made a mistake not getting self heated LifePo4's. Summer performance is absolutely great (4x longer than deep cycle), but winter performance is awful. Wish I knew before buying these.
I finally had to install a heater, which allows them to charge and discharge correctly - untill that "freeze up" occurs again in a couple hours. When that happens, it happens fast and with no notice. That sucks because every just stops without warning.
I used a corded "gutter/de-icing heater" connected to my shore power.
