Rapid Charger Electrical Efficiency

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  • Updated 5 years ago
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  • (Edited)
I am monitoring the amount of electricity used by my 4.0ah and 2.0ah battery.  I have used the regular charger exclusively for several months.

Now, I've used the quick charger, and recorded 270 watts into the 4.0ah battery.  Which is much more than the battery capacity of 4.0ah @ 52 volts.

I know that some of the electricity is used to run the fan, and of course there is a bit of loss of efficiency with the charger itself.

But I'm wondering if anybody ever measured the amount of electricity going into the battery compared to the amount used from the outlet.  I would think this would be something good to know as people monitor their batteries.
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Posted 5 years ago

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Official Response
Your missing Root mean square(rms). This is the difference between AC(Alternating Current thanks Tesla) and DC(Direct Current, stupid Edison). Your measuring AC so to convert what the battery holds in AC watts you must multiply 270 by .707( or divide by 1.414). If you measured 270 watts, multiply that by .707 or divide by 1.414. This is the watt difference between a DC battery and AC charging. So 270*.707 =Equivilent to charging your battery with 191 watts so your battery had a little left in it. In electrical calculations, watts are watts, but a 4 ah battery at 56 vdc has 224 watts, it would require 224 watts * 1.414 317 watts measured in AC to charge with an AC supply.