Lithium Batteries in cold weather

You'll get better responses at BBC. Bunch of Northern types posting there.

It will work but you'll probably have somewhat less battery capacity. Probably not an issue though if the battery is being used for a trolling motor or lights, fish finders, etc. and you always have plenty of battery capacity in warmer weather. If you have an electric outboard motor that could be an issue of having reduced battery capacity. If you have some concern, if you could warm the battery before using it, i.e., take another battery and connect a small heating blanket and wrap that around the battery to get it warmed up that might help.

I have lithium batteries that I use in my boat. I had a similar concern, and I talked to a very knowledgeable Tech Support guy at Powerhouse Batteries. He said he lives in Michigan and keeps his boat outside year round. It's covered to keep the snow out of the boat, but he said he uses his boat in cold weather. He said never removes his lithium batteries.

Lithium batteries are more temperature tolerant than flooded lead-acid batteries. Many can charge just fine in near-freezing temps, almost every li-ion battery pack and charger worth a crap will have a temperature sensor to know the proper charging strategy for the ambient temperature. If it's too cold then the charger will simply not charge the battery until it's warm enough. If it's going to get well below freezing then pull the battery and keep it inside, if it's near freezing then just make sure the battery is topped off or on a float charger. They also make automatic battery warming blankets.

LINK

I just use them trolling motor and electronics. Ordering the heaters, thanks for the link. Thanks everyone else, think I’ll just pull them when we have really cold stretches.