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    Lipo battery mAh vs Wh

    Hi,
    I am a bit confused about the the mAh and Wh specifications for a 3.7v lipo.

    For example I have a routejade battery YE402025C 3.7V 160mAh, 0.592Wh.

    Now I have a varta batter VKB: 56416 201 026 which is 3.7v 150mAh, 0.6Wh.

    So is there no relation between mAh and Wh for a battery ?

    Till now I thought if we know mAh we can calculate Wh since the average voltage is 3.7v but now I am a bit confused how can these two things (mAh and Wh) is not relative ?


    My assumption till now was that ( 3.7 * mAh (in A ) * 3600 ) Joules is the total capacity of battery in terms of energy. Is this not correct ? Coz the Wh is not matching properly with this value.
    All waveforms, no matter what you scribble or observe in the universe, are actually just the sum of simple sinusoids of different frequencies....

    •   Alt19th May 2017, 15:04

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  2. #2
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    Re: Lipo battery mAh vs Wh

    It is just rounding of the results of V * A * 3600 - or at least that can be part of the reason for the difference.
    Additionally, the Watt hours is the volts * amps under the area of the discharge curve, which is not maintaining a constant 3.7VDC as the battery discharges - and the voltage will change depending on the rate of discharge.

    To get a completely accurate result, one would have to apply a constant current load and integrate the voltage curve to obtain the result. But, this level of accuracy is seldom necessary, and the simple
    V*I*3600 is often sufficient.

    Additional note - one cannot FULLY discharge a LiPo battery without incurring some amount of permanent damage/diminished capacity. Discharge below 1V / cell will almost surely reduce capacity, and generally it is avoided to discharge below approximately 1.7V to 2V per cell to maintain longer life.

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