Chagrin:
Cerin:
Are you using anything like a solar charger shield? Can those use an arbitrary external power source instead of a solar panel to recharge the battery?That shield is designed specifically for a single cell lithium battery. Can't change the output voltage.
To charge a lead acid battery a ready made solution would be called an "on board battery charger" (example). In real world use they are designed to stay permanently attached to a car/boat and then plugged in to a wall socket to maintain the battery.
For a non-ready-made solution I'd look at something like a UC3906. Lots of examples from Mr. Google on this.
Thanks, but I was referring to the input source, not the output. e.g. charging the single lithium from a wall supply instead of a solar panel. If it expects a certain voltage/amperage from the solar panel, what would be the problem in getting that instead from a wall adapter?