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  1. #1
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    8.4v power cell not charging?!?!

    I just bought a really good looking used slash 4x4 with the 7 cell 8.4. The guy said he hasn't ran it in a really long time. Any way to get some life back into the pack? I have ran two discharge/charge cycles on it and it seems to be getting more mah but i am not sure if its helping....or if its even safe to keep doing this?

  2. #2
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    Quote Originally Posted by wesman_86 View Post
    I have ran two discharge/charge cycles on it and it seems to be getting more mah but i am not sure if its helping....or if its even safe to keep doing this?
    Sometimes it takes a few cycles on the charger and a few runs in the car to fully revive a dormant NiMh. Just keep at it. You're not going to hurt the pack. I suggest doing a voltage check after charging to see where it's at and compare it to the previous charges. Max for a 7 cell NiMh should be in the area 9.8V for the whole pack.
    Last edited by zippogeek; 02-22-2013 at 08:49 AM.
    Make it idiot-proof and along comes a better idiot

  3. #3
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    Google form charging for NiMh... that procedure could bring it back to life.

    I have had a 7 cell NiMh as high as 11.2v.
    Whatever it is I just said... I could be wrong.

  4. #4
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    Quote Originally Posted by Jimmie Neutron View Post
    I have had a 7 cell NiMh as high as 11.2v.
    How is that possible...are you sure you don't mean 8-cell? I based my suggestion on the traditional 1.4V per cell value (AFTER charging).
    Make it idiot-proof and along comes a better idiot

  5. #5
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    Charge it at 1-2 amps slow charging an cycling is the key for refreshing a battery . JMO
    1 Rusty VXL

  6. #6
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    Quote Originally Posted by zippogeek View Post
    How is that possible...are you sure you don't mean 8-cell? I based my suggestion on the traditional 1.4V per cell value (AFTER charging).
    Nope... 7 cell.
    Charging at very high rates is an old racers trick to get the most power out of a NiMh. Doing so shortens life span but pumps extra voltage into the cells... 1.6v in most cases.

    Anywhere between 1.4-1.5 is normal voltage for a full NiMh.
    Whatever it is I just said... I could be wrong.

  7. #7
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    Quote Originally Posted by Jimmie Neutron View Post
    Nope... 7 cell.
    Charging at very high rates is an old racers trick to get the most power out of a NiMh. Doing so shortens life span but pumps extra voltage into the cells... 1.6v in most cases.

    Anywhere between 1.4-1.5 is normal voltage for a full NiMh.
    Interesting!
    Make it idiot-proof and along comes a better idiot

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