Reconditioning rechargable batteries

Discussion in 'General Electronics Chat' started by m4yh3m, Dec 5, 2008.

  1. m4yh3m

    Thread Starter AAC Fanatic!

    Apr 28, 2004
    I remember seeing one of my electronics teachers zapping a battery towards the end of class to recondition it so it will hold charges again. Any info on how to properly do this? It's for a moto razr cell phone
  2. jpanhalt


    Jan 18, 2008
    I charge up a capacitor to, say 12 V, for sparking a single 1.2 V NiCd cell. I have never done it with any other cell type (e.g., NiMH or any lithium), nor do I think it would work with them. The capacitor size is not critical; anything over 1 uF should be enough.

  3. Audioguru


    Dec 20, 2007
    I have zapped old Ni-Cad cells that became shorted inside.
    The cells were AA size. I used a 3300uF capacitor charged to 9V.

    Your phone is probably about 4 years old and its lithium battery is worn out and needs to be replaced. If you zap a lithium battery then it just catches on fire.
  4. m4yh3m

    Thread Starter AAC Fanatic!

    Apr 28, 2004
    And that -- is why i love you guys, and continue to tell people i know/run across who like electronics about the website. That is very good info to know. Appreciate it!
  5. Jassper

    Active Member

    Sep 24, 2008
    Worse case it will explode. :eek:
    Lithiums don't recondition well - if at all.

    But in case you are interested, to recondition or "equalize" other battery types like NiCad, Gell, Lead Acid, or AGMs. You want to charge them at about a 1 to 1.5 volts higher than their rated charge voltage. However, you need to regulate the charge current to a very low level.
    This applies to large capacity batteries, for smaller ones like AA's and such, Zapping them with a capacitor as described above works well. I remember building a NiCad AA and AAA battery Zapper/Charger from an electronics magazine about 16 years ago, it worked about 50% of the time.

    The Theory behind this is to "shake" or burn off the Sulfating that has built up on the plates inside the battery. Depending on the severity, this may or may not work, but always worth a try.

    If you are using a bank of batteries it is best to recondition them one at a time rather than the entire bank, if possible. Banks that are sealed inside a case are hard to do individually obviously. Another thing to remember about banks is if you have one battery in the bank that is bad, it is best to replace the entire bank rather than just that one battery. Think of it as parking a new Porsche in the middle of a Used car lot, guess which one gets the most attention. ;)