Lithium Battery heater
I seek information on what others use to heat batteries when it is cold. I am leaning towards 12 volt heating pads of some kind. I am not sure how warm my battery compartment stays when the heat is on...
Forum Discussion
IMO, it's just a matter of time before all 12v, consumer-grade, lifepo4 batteries come standard with internal heating pads. It's far from rocket science, plus the costs for manufacturers to add a few silicone heating pads and a BMS with a heating pad terminal are minimal. Consumers wanted low-temperature cut-off, they got it. Internally heated batteries are next.
On a sidenote, some may not know that cold weather operation of lifepo4 batteries negatively affects discharge performance in addition to charge performance. Dropping the temperature of a lifepo4 battery from 77f to 32f can reduce the battery's total ah output by approx. 10%. This means a battery that produces 100ah at 77f may only produce 90ah at 32f. Not only is the ah output reduced, the maximum continuous discharge current the battery can safely produce is also reduced. In other words, powering a microwave while your lifepo4 battery sits in sub-freezing temps may not be doing your lifepo4 battery any big favors.
During the winter we keep our lifepo4 internally heated to a constant 55-60f (cell temps), 24/7. We do this to: 1) maximize ah output (any increase here helps power the heating pads), and 2) lower the risk of reducing cycle life with any high current discharges. Plus, it goes without saying . . . we also retain full charge capability, 24/7, too. For us, a win-win-win.
On a sidenote, some may not know that cold weather operation of lifepo4 batteries negatively affects discharge performance in addition to charge performance. Dropping the temperature of a lifepo4 battery from 77f to 32f can reduce the battery's total ah output by approx. 10%. This means a battery that produces 100ah at 77f may only produce 90ah at 32f. Not only is the ah output reduced, the maximum continuous discharge current the battery can safely produce is also reduced. In other words, powering a microwave while your lifepo4 battery sits in sub-freezing temps may not be doing your lifepo4 battery any big favors.
During the winter we keep our lifepo4 internally heated to a constant 55-60f (cell temps), 24/7. We do this to: 1) maximize ah output (any increase here helps power the heating pads), and 2) lower the risk of reducing cycle life with any high current discharges. Plus, it goes without saying . . . we also retain full charge capability, 24/7, too. For us, a win-win-win.
