Solar and lithium batteries
I've got some spare solar panels and I'm wondering about charging lithium batteries. For the most part, these batteries came with boxes and cig lighter plugs to charge from the 12v system. Of course that gets up around 13.8v or so during travel, so I assume they can handle that. There doesn't seem to be a way to figure what the top end is though, but I assume they have circuitry to prevent say the use of 14+v. But not sure.
So...how to charge these with a panel? I've got one that does 18v, for instance, and another at 22v, measured in full sun with no load. I first thought of attaching a step down I had that can take up to 30v and output 3, 5, 12, etc. But can I assume that the battery charger for the lithiums I'd connect would be one way, in essence? Or should I use a spare Sunguard 4.5 amp controller and then the 12v charger for the lithium battery?
I realize there are special controllers for these batteries, but are they for bare battery packs? I would think so, since all the batteries I have are meant to be charged with wall warts, USB or car DC power.
But before I blow myself up thought I'd get it sorted....
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2001 Ford E250 Sportsmobile with Salem-Kroger 4x4 conversion
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