I was wondering if it was possible to add a led indicator that lights up when charging starts and turns off when it is done. Also does anyone know if stops charging when the batteries reach maximum capacity?
I'm sure you mean when the battery is fully charged, right? Because the capacity is a property of the battery (changing with lifetime), but not of the charge status. And yes, if connected properly the MAX713 stops charging (or goes into trickle charge mode) when the battery is full.