I wanted to find out how to extend lifetime of Powerwall 2 in Backup-only mode. The current Tesla app does not provide a way to set maximum SOC lower than 100%. I realize that 100% is probably a lower % of real capacity.
I have read in numerous places that lithium-ion batteries stored at high SOC result in increased chemical reactions and faster reduction in capacity. Temperature is another major factor, but the batteries are installed in basement and are not exposed to extreme temperatures.
Even though Tesla does not provide a setting to limit SOC for backup-only mode, I was able to tweak Time-based control mode to achieve that goal, and right now, the Powerwalls are running at 75% SOC.
I am fine with a lower SOC for a rare outage event. StormWatch will handle cases where the risk is known to increase. And in case an outage occurs, solar system will charge them to full capacity when weather permits.
If keeping SOC at 75% and the batteries lifetime extends several years, then it would be worth the trouble. Anyone knows of research that shows how battery life is affected at various SOC storage?
I have read in numerous places that lithium-ion batteries stored at high SOC result in increased chemical reactions and faster reduction in capacity. Temperature is another major factor, but the batteries are installed in basement and are not exposed to extreme temperatures.
Even though Tesla does not provide a setting to limit SOC for backup-only mode, I was able to tweak Time-based control mode to achieve that goal, and right now, the Powerwalls are running at 75% SOC.
I am fine with a lower SOC for a rare outage event. StormWatch will handle cases where the risk is known to increase. And in case an outage occurs, solar system will charge them to full capacity when weather permits.
If keeping SOC at 75% and the batteries lifetime extends several years, then it would be worth the trouble. Anyone knows of research that shows how battery life is affected at various SOC storage?