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  1. #1
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    Rewiring MS battery will charger still work?

    Just like the title says, I am building a single XML (lFlex driver) for a friend that has a couple of Magicshine battery packs. I am thinking that I can open the pack up and rewire it to 1S4P (ie: 3.7v, ~8800ma, assuming they are 2200 mAh each) and put them to good use. I assume the packs can be rewired like any pack, but am wondering if anyone knows if the charger will still work with this new configuration. I have searched around and have been unable to find the info, and I do not have the MS batteries and charger in my hands. I would imagine there are a few people out there who might consider using their MS packs this way. Appreciate any insight someone might have.

  2. #2
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    The charger won't work since it's 8.4V charger for 2S2P battery pack.

  3. #3
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    Thanks Toaster. I appreciate the reply. I did assume that the charger might cover too narrow a window to do the job, but without one in front of me I needed to ask someone else. I would assume if I re-wired the pack to the 3.7v 8800 mAh (1S4P) I could use the below charger. Is this correct? I have only worked with NiMH batteries in all my past light systems and am just now moving to Li-ion batteries so I am still learning the details. Thanks again.

    http://www.batteryspace.com/smartcha...-ullisted.aspx

  4. #4
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    You'll also need a different protection PCB in addition to a different charger. The protection PCB built into that pack is specific to an 8.4v 2s pack. You'll need a 4.2v 1s protection PCB. Given the really poor quality of the cells in a magicshine pack, I'm not sure you wouldn't be better off starting from scratch.

  5. #5
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    Ahhh. Learned a little more yet. Didn't realize the pcb's were specific to the voltage of the packs. It does sound like more trouble than benefit to convert the MS packs. Moving on....

    Thanks again for the knowledge!!!!

  6. #6
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    Since you'll be using flex driver, you don't need the PCB. You've got the driver with that function, and a charger, that charges batteries to 4.2V, so you've got nothing to fear and no need to spend extra $.

  7. #7
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    If you do rewire the pack and not install a new protection board, I would be very careful charging it.
    I wouldn't leave it unattended, and make sure you unplug it once it is done.
    It is my understanding that without the protection board, it can trickle charge to unsafe voltages if left on the charger.
    You'll need to get a new charger like the one you linked to.....and while you are at it, you may as well order a new PCB with it.
    Look, whatever happens, don't fight the mountain.

  8. #8
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    Quote Originally Posted by Toaster79
    Since you'll be using flex driver, you don't need the PCB. You've got the driver with that function, and a charger, that charges batteries to 4.2V, so you've got nothing to fear and no need to spend extra $.
    It just depends on the level of risk you think is acceptable. Protection PCBs aren't meant to be the normal cutoff for high or low voltage. They are suppose to be a fail safe if something else goes wrong. If you rely on the LED driver for low voltage cutoff and the voltage regulation of the charger for the upper voltage protection, then it will work right as long as you don't have a failure in either of those circuits. But we've all had electronics fail. It's really not so rare. Adding a protection PCB means you have to have 2 concurrent failures before something bad happens. That makes the odds of a safety issue extremely rare to the point that I'm not going to worry about charging the batteries in my house. I'm not really interested in hanging around baby sitting my batteries while they charge. I think that's worth the expense and effort of having a protection PCB.

    The protection PCB also protects the pack from shorts in the wiring and connectors between the battery and the light head. Again, something that's really not all that rare.

  9. #9
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    Thanks again for the information. Not 100% sure yet, but my buddy has two of the MS battery packs and I am leaning back toward trying them. It seems a waste to just let them set. May go ahead and re-wire with the appropriate pcb and new charger (will be able t use the charger for any other 3.7 volt packs for XML) and see how it works out. At the very least, I become a little "smarter" for the process. After all, this is why we DIY, right?

    Thanks again for the knowledge. Its good to have people's support on this forum!!

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