I'm planning to install a solar power system in my detached garage over the next year, including about three solar panels and two 100AH batteries. The purpose is to provide lighting, run trickle chargers, security cameras, and occasionally power tools. However, I'm concerned about how well lithium batteries perform in extremely cold temperatures—we sometimes experience overnight lows below 0°F, and single digits can last for weeks. Will lithium batteries work well in these conditions, or should I consider using lead acid batteries instead? Thanks in advance!
3 Answers
Some BMS systems can help keep lithium batteries warm by maintaining a slight discharge during the cold months. If you're not pressed for space or weight, lead acid or AGM batteries are very reliable. You may also want to think about a heating system to keep the batteries in their ideal temperature range, although that might increase your battery bank size.
I just finished this for my shed at a seasonal home—went with SLA batteries. The BMS drain and additional costs for lithium felt unnecessary.
Got a recommendation for a thermostatic heater for battery storage? A 12 VDC would be ideal!
Many lithium batteries feature internal low-temperature cutoffs in their BMS that prevent charging below 32°F and discharging below 0°F, especially with LiFePO4 types. You could place them in an insulated enclosure, like a toolbox, and add a small heater inside if it gets too cold. This setup would give the batteries some natural warmth during operation. Also, consider getting LiFePO4 batteries that already have internal heaters to simplify things.
For cold climates, I generally prefer sealed lead acid (SLA) or AGM batteries since they handle low temps better than lithium. Lithium batteries can struggle when it gets to freezing (32°F).
If there’s a chance of freezing, look for lithium batteries with built-in heaters.
True, but many lithium batteries come with options for heating pads, or you can store them in insulated boxes to help keep them warm.
I totally get that reasoning! I’ve noticed every tutorial seems to rave about lithium for storage. But with the risk of freezing, I don’t want to take chances.