I have an application that requires 2 12V 7.5 AHr lead acid batteries to be charged from 2 nominally 12V but actually nearer 18V with no load
1.5A solar panels, in the end i hope to get away with 1A solar panels but first I need to accomodate 1.5A panels. I don't just want to put a diode in series for risk of overcharging the batteries.If I could find a suitable charge controller at a reasonable price I could buy them in, but I cannot find one.
so looking at building something, I have PIC in circuit anyway for other reasons, I am considering PWM'ing the solar output to keep it at 27.6V but this area is new to me, indeed I am not sure this is the best approach, any ideas on whether this is a suitable approach or if not what is?
Pete D