Getting a 24v scooter motor to work

Discussion in 'The Projects Forum' started by Gdrumm, Aug 30, 2008.

  1. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
    I bought an old electric scooter, with no battery charger.
    At first, I charge it with another 24v charger from my weed eater, and it worked.
    Later, thinking I might burn up my weed eater charger, I disconnected the two 12v batteries from each other, and charged them up with a 10 amp car battery charger, then reconnected them.

    Now, the little electric motor will only "bump" when I use the speed pot.

    Any ideas as to what I've done wrong?

    I even drained it all, and recharged it on my weed eater charger, and it's doing the same thing.

    Any ideas appreciated.

  2. SgtWookie


    Jul 17, 2007
    Hi Gary,
    It's very likely that the batteries are no longer any good.

    It's not too likely that you did anything to cause their demise. Perhaps the 10A charger was a bit much, if it wasn't regulated.

    Lead-acid batteries have an annoying tendency to develop shorted cells when they reach the end of their life. This is usually caused by accumulation of debris in the bottom of the cells, caused by corrosion of the plates.

    The best defense against this is to keep the batteries charged to at least 12.7v.

    Another primary cause of battery failure is plate sulphation. This is a layer of gook deposited on the plates that begins when the battery voltage falls below 12.4v. The longer the battery stays undercharged, the more quickly the gook builds up. After a while, the battery will no longer accept a charge, nor will be able to discharge.

    You need a fresh pair of batteries.

    After you obtain the batteries, let's talk about building a proper charger for you. Or perhaps, you wish to build the charger ahead of time, which is also do-able.

    But whenever you wish to do this, we will need to know the model of the batteries, or their AH rating.
  3. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
    Thanks for that, I'll get back to you after the weeked.