I have made my 24v scooter run from 7 lifepo cells (10ahr)
I have put a 5v 5w solar panel on each cell.
I like this better than charging a string and worrying about balancing.
I never run it down too far and leave it in the sun 2 or 3 days. Between rides. Luckily it never seems to overcharge the cells as they are all around 3.3 v when ever i measure them.
Complex question, but what is the optimum voltage to charge cells at in theory. Would i be better with a 4v 5w panel?
Im wondering if a cell charges proportionally to the voltage? In theory does a 5v 1amp charger put power in better than a 4v 1.25a charger?