Hacker News Reader

In my layman's understanding of batteries doesn't the resistance of a battery increase with its level of charge? If so wouldn't these large batteries have so much resistance that at a reasonable level of charge most or a large portion of the energy would be lost as heat? Does it somehow charge individual cells as opposed to the whole thing or am I way off base?

View on HN

That's not at all how battery charging works.

Whatever the voltage output of the solar panel is, you can always step that up or down.

The batteries go up in voltage slightly when they are charging, but not much relatively.

For a typical LiIon cell, it may be at "0%" at 3.4V (you don't want to drain it all the way). And "100%" full is around 4.2V.

As long as you can supply at least 4.2V, it will charge up to that point.

Reply on news.ycombinator.com