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  1. #1
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    How much is too much? Is my Magicshine charger overvolting my battery?

    Sorry for the newbie question but I searched and couldn't find a answer. I've read several things concerning how you shouldn't let the batteries discharge to low, anywhere from 3.7v down to 3.0v, but i haven't read anything on how high you can let them go before is creates damage or becomes dangerous.

    My charger for the mj-880 is putting out 8.57v as measured from the plug with my fluke meter. Is the 1.57v over the spec'd 8.4v maximum going to hurt anything?

  2. #2
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    Found a answer in case anyone else has the same question.

    "Although higher voltages deliver increased energy densities, cell oxidation severely limited the service life in the early graphite cells that were charged above the 4.10V/cell threshold. This effect has been solved with chemical additives. Most commercial Li-ion cells can now be charged to 4.20V. The tolerance on all Li-ion batteries is a tight +/-0.05V/cell."

    from this article -

    Chapter 4: Proper Charge Methods

  3. #3
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    the only thing that hurts will be

    a) trying to charge a freezing cold pack (as in: come in from a winter ride) let pack warm up first or even charge next day

    b) allowing volts to drop below 2.7 volts per cell (5.4 volts for 2s)

    your charger is fine, it will not work at all before it over-volts a pack. the charger uses a generic charging pcb that 99.99% the world uses. it will just crap out someday but not overvolt a pack

  4. #4
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    Quote Originally Posted by 127.0.0.1 View Post
    your charger is fine, it will not work at all before it over-volts a pack. the charger uses a generic charging pcb that 99.99% the world uses. it will just crap out someday but not overvolt a pack
    In fact, I myself have seen several cheap wall chargers (from budget bike light sets) with incorrectly set voltage limit, heavily overcharging the battery...

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