The Unexpected Usefulness Of 500 mA Chargers

[Phlogiston]

Slower chargers are also nice if you’re using a solar panel for power.

There are times when you might not have perfect conditions - weak sunlight shining through hazy clouds, for example. If the panel can only sustain 750mA, the 500mA charger will work, but a 1A charger will try to draw too much power and the panel voltage will crash. Many chargers will simply refuse to work under those circumstances; they won’t even fall back to a lower current.

This is a case where you’re better off with a simple charger using something like the venerable TP4056 chip instead of the latest LCD multi-current, multi-chemistry, microcontroller-based charger. As long as the solar panel voltage is at least a little higher than the cell voltage, you’ll at least get some charge, even if not much.

@EDCba

Note: 500 mA is the input, not the actual charge current. The actual current going into the battery will be higher as the voltage is reduced from 5 V to 3-4 V. A lot of people talk about the current in as if it’s the actual charging current.

Only if the charger has a buck converter. Chargers with linear regulators just dump the extra power as heat and the cell actually does get the same current as you see going into the charger.