Hello, I have a 1 foot square solar panel that is flexible. It is supposed to be capable of 100 ma. output and the open circuit voltage in bright sun
is about 16 Volts. (I am limited to this panel size for this application.) It is connected to a small charge controller circuit (Amazon) that charges a
12 Amp hour SLA battery.The battery is only used for engine starting so it usually is not drained much. I have connected the charger output to the battery through a Schottky diode (low voltage drop) as I don't know if the charge controller would tend to drain the battery overnight without it. Yesterday in late afternoon sun I measured the panel output at 13.1 Volts, the charger output at 12.88 Volts and the battery voltage at 12.65 Volts (indicating the diode drop is 0.23 Volts). The system had been sitting in bright sun all day and I was hopeful the battery would be closer to 13 Volts.
Because the panel output is only 100 mA. would it be better to connect the solar panel directly to the battery? Should I keep the diode between them? My goal would be to keep the battery around 13 Volts.
is about 16 Volts. (I am limited to this panel size for this application.) It is connected to a small charge controller circuit (Amazon) that charges a
12 Amp hour SLA battery.The battery is only used for engine starting so it usually is not drained much. I have connected the charger output to the battery through a Schottky diode (low voltage drop) as I don't know if the charge controller would tend to drain the battery overnight without it. Yesterday in late afternoon sun I measured the panel output at 13.1 Volts, the charger output at 12.88 Volts and the battery voltage at 12.65 Volts (indicating the diode drop is 0.23 Volts). The system had been sitting in bright sun all day and I was hopeful the battery would be closer to 13 Volts.
Because the panel output is only 100 mA. would it be better to connect the solar panel directly to the battery? Should I keep the diode between them? My goal would be to keep the battery around 13 Volts.