PowerPak Pro 2.5x2 balancing

  • Hi Richard,

    Last weekend i had a crash with my aircraft. I had a PowerPak pro 2.5x2 installed

    Externally the battery looks perfect, case is perfect no cracks etc

    I took the Powerpak pro apart and measured the cell voltages. They were .2 volt different from each other

    On charging, one cell reached 4.3volts the other reached 4.10 volts at the end of the charge

    I also tried installing new identical Samsung cells. But this made no difference

    Can you tell me how close your balancer works? What difference in cell voltage is acceptable?

    . I'm afraid going to 4.3 volts for the one cell is too high, from my experience

    Maybe i damaged something internally. There were no loose components inside the case

    Your thoughts please

    Happy New Year

    Thanks for your support


  • Hello,

    the charger can´t charge up the cells different. This comes over time.

    The balancer gets active when on cells exceeds 4.20V

    So if you already replaced the cells and see again 4.10 to 4.30 I have no explanation to that, only that your measurement was not correct?

  • Thanks Richard,

    Yes i agree my meters are very slightly different, they have served me well. Please see pictures attached relating to cell differences. At this point the charger was still charging, the light hadn't turned green on the Powerpak. Picture one cell one, picture two cell 2

  • Hi Richard,

    Maybe i did not make myself clear enough

    I used two different meters to test the battery, to minimise inaccurate readings. They are old meters i know. But they should be good enough to demonstrate the difference between the cells

    The two meters were hooked together (probes shorted so as a common single probe). The photos were taken a matter of seconds apart

    Photo one meter leads joined together

    Fluke meter

    BBC meter

    Measuring cell one

    Photo two meter leads joined together

    Fluke meter

    BBC meter

    Measuring cell two

    Hope this makes sense


  • Thanks Richard,

    So can i assume that full voltage per cell should not exceed 4,10V?

    Having one cell charge to 4.3V is getting very high in my opinion

    I'll retire this battery pack due to safety reasons