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These Batteries Can Be Recharged By Hand — Parallax Forums

These Batteries Can Be Recharged By Hand

Comments

  • wjsteelewjsteele Posts: 697
    edited 2011-04-16 04:04
    I think it would be cool to have a solar cell on each one as well! Maybe the outer skin is one of those flexible printed cells. That way, they always top them selves off, as well!
  • whickerwhicker Posts: 749
    edited 2011-04-17 22:34
    hmm,

    AA cell
    2200 milliamp-hours
    2.2 amp hours

    want watt-hours

    multiply cell voltage 1.5 * 2.2
    3.3 watt-hours

    1 watt-hour = 0.8598 calories (nutritional)
    3.3 watt-hours = 2.83 calories (nutritional)

    not infeasible.

    assuming 20% eaten to muscle conversion efficiency
    assuming 70% generator efficiency
    assuming 50% charging efficiency

    2.83 * 1/0.2 * 1/0.7 * 1/0.5 = 40 eaten food calories
  • ercoerco Posts: 20,260
    edited 2011-04-18 11:13
    Interesting, but I think a hand-crank charger for standard NiMH rechargeables would make more sense. BUT I can't find one! Here's an opportunity staring us in the face. This homemade unit is all I found so far: http://www.zetatalk.com/energy/tengy05n.htm and I suspect that's not the most efficient way to do it!
  • Beau SchwabeBeau Schwabe Posts: 6,568
    edited 2011-04-18 11:53
    erco,

    Well, now I know what to do with a few cordless drill's that >ate< batteries!!! Time to give it back Mr Drill!! .... personally I prefer a corded drill, hate delaying a project due to dead batteries.

    Thanks erco!

    Maybe I'll hook the power supply of two drills back to back, that way I could get one of the kids to turn the crank on one drill, while I did the actual drilling on the other drill. ( joking )
  • ctwardellctwardell Posts: 1,716
    edited 2011-04-18 12:14
    Maybe I'll hook the power supply of two drills back to back, that way I could get one of the kids to turn the crank on one drill, while I did the actual drilling on the other drill. ( joking )

    Maybe you could use three drills, connect all the power supplies and connect two of the drills chucks together, the third one will be used to actually drill. Give one of 'em a spin to get started and you will have a perpetual drill.

    C.W.
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