Sondors Battery Charging Details

You may not care about this stuff, unless you have an electric bike. If so, read on…

For those curious, and without a Kill-A-Watt meter, the standard Sondors THIN battery (and Original which I also have), on the standard 2 Amp charger, starts out charging at about 1.45 Amps, 88W, when there’s only about 34V left. When it has charged for 2:50, it’s dropped to .33 Amps, 21 W, and 220 Watt.hours have been put into the battery.
10 minutes later it’s .28 Amps, and 18 W, with no detectable increase in the 220Wh delivered. This is what I’d expect, knowing a little about how lithium-ion EV batteries charge. Some vehicles suggest charging to 80%, and not to 100% to extend the life of the battery (if overheating is avoided). It’s not really possible to do this with a Sondors charger, without a Kill-A-Watt meter to tell you when it’s almost full.

For those less familiar with electrical figures, that means that the battery could run for about 220 Watts (plus what it had remaining before charging), for a full hour. Those with the LCD which can display Watts currently being used, will notice that Pedal ASsist 1 gives about 80W of thrust. I’ve heard that a fit cyclist can generate 150W of power by pedaling a bicycle.


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