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Old 01-19-2009, 01:26 AM   #14 (permalink)
MPaulHolmes
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Location: Maricopa, AZ (sort of. Actually outside of town)
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That's what I do too! I have 6 12v 6amp chargers ($20 each). It keeps them balanced, but it's pretty slow. When each one is done, it's charger shuts itself off on it's own time.

I'm going to read up on transformers and voltage doublers and who knows what!? I think it's a great idea to start with a really high voltage so the charger could work for anything from an AC system to a DC system. You could have a little knob on the side that would select what voltage you want to charge at. You could have another knob that would select if it's Lead Acid, NiMH, or Lithium Ion. Each algorithm is well defined. It's just a matter of controlling voltage and current based on some sort of feedback from the batteries. Wouldn't that be cool!? It might be good for there to be 2 knobs for voltage, so there could be 10, 20, ..., 320 (or whatever), and the other 0.0 through 9.9. Lithium Ion are weird. Each cell is 3.7v. The Lithium Ion batteries have almost the same charging algorithm as Lead Acid, as far as I know. NiMH is totally different. None of them are very hard with a micro-controller though, and a little high school math! I love how you can use math in the real world! It actually makes real stuff work. It's weird!
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