changing 12 volts gel cell battery using solar panel

Thread Starter


Joined Jan 20, 2009
when changing 12 volts gel cell battery using solar cell is it better to have higher voltage or higher current to full the charge the battery.


Joined Nov 18, 2012
Gel cell batteries are sensitive to charging voltages. High voltage will damage the battery. Refer to the manufacturers specs for the proper voltage. As for current, low current slow charge will always be the best no matter what kind of battery.


Joined Aug 27, 2009
It's heat that's the main cause for battery degradation and gel cells are sensitive due to their physical construction. For systems designed with good thermal management (passive as with large traction batteries or active as with many Electric vehicles liquid cooled BMS systems) the rate of recharge has little impact on battery life as simply charging at any rate itself degrades the battery with elevated temperature of the chemistry increasing capacity loss.
The four BEVs driven in Phoenix, Arizona were faced with a hot climate, and two were fast charged twice as often as recommended by their manufacturer. Despite these conditions, the vehicles were operated without failure for 50 thousand miles. A greater loss in battery capacity was observed for the fast charged vehicles, though the difference compared to the level two charged vehicles was small in comparison to the overall capacity loss. The vehicle operation was, as intended, verified to be very similar between test groups, and the largest difference in conditions noted was battery temperature during charging. Hotter ambient temperatures appear to have accelerated capacity loss for all of the vehicles in the study, though the exact relationship remains to be seen.