Few Questions About The Construction of A Balance Charger

Discussion in 'The Projects Forum' started by Amit Ika, Jul 4, 2016.

  1. Amit Ika

    Thread Starter New Member

    Jul 4, 2016
    Hey guys,

    As the title implies, I am trying to build a balance charger based on this project:
    The project which I linked above is of a charger that charges one double A battery using an Arduino microcontroller. I am looking to build a charger much the same except instead of one double A, I want to charge three cells in series (you may ask why I would want to do this instead of just buying a charger and the reason is long winded. Suffice to say that I am going to build it.) I know this will involve balancing each cell as is diagrammed in: http://cdn.instructables.com/FA8/JBBJ/GSFTZI3H/FA8JBBJGSFTZI3H.LARGE.jpg ( mine will just be three cells in series unlike this diagram)
    In my project, there will be a lead between each cell in series. My question is what to do with those leads? I know that after one of the cells has reached its max voltage, you want to keep it from exceeding its voltage while continuing to charge the rest of the cells and you accomplish this by doing something to the leads around the cell which has reach maximum voltage. What do you do with those leads? I tried to do some research but didn't come up with much information on this topic. My current theory is that you run a mosfet between the leads of the battery that has reached maximum voltage and control it via pwm to maintain its voltage. Is this correct or am I pulling this from fairyland? Any help is greatly appreciated!
  2. DGElder


    Apr 3, 2016
    A zener diode rated at max allowed cell voltage?