Mustang65, Thanks for the update. That is exactly to results I experienced. It appeared, in my experiment, the solar cell only had a MINOR influence on the life of the battery and what I actually experienced was just the typical life of the 1.2v battery in a scenario similar to yours. Not sure, but I think I didn’t have enough current from the solar to fully charge the battery each day. If you come up with a solution, please advise and I will do the same. Frank Sent from my iPhone using Tapatalk