Streetlight and Load Output Settings advice on LFP

[TherealKT]

I have a project where I will be replacing old gel batteries in a bunch of solar powered streetlights. The batteries are charged with a 180 Watt panel via a small, cheap, PWM controller. There is also an LED driver installed between the load output and LED lights. I am going to be installing 12V LFP batteries and replacing the old controllers with SmartSolar 75/15 MPPTS. I would like some advice on some of the settings please.

1. What would be the best on/off voltage settings in the Load Output settings for LFP batteries?

2. What would be the best on/off voltage settings in the Street Light settings? According to the manual 11.4V is the lowest detectable voltage. I am inclined to go with that.

Any other advice would be appreciated.

[MikeD (Mike)]

Best off voltage for LiFePO4 is ~3V/cell or maybe as low as 2.8. below that there is very little energy stored, and the higher cut off protects the battery better. However, if you don’t have access to individual cell voltages then assume that n-1 are at 3V and one is at 2.8V, so for 12V system min cut off should be no lower than 11.8V.