How to Calculate the Battery Capacity of your Electric Bike?

[Anton]

Electric bike battery capacity is most commonly calculated in Watt-hours (Wh). It's the same measure as your household electricity bill which is in Kilowatt-hours (kWh).

To calculate your electric bike battery capacity, you need to multiply the batteries Voltage (V) by it's Amp-hours (Ah).

For example lets take a 52 Volt electric bike battery with 20 Amp-Hours:

52 V x 20 Ah = 1040 Wh (Watt-hours)

This is referred to as the batteries nominal capacity and it is a simplification of the actual capacity. The actual battery capacity is slightly different and depends on a multitude of factors such as temperature, discharge rate, age, how high it is charged, but what it comes down to is actually measuring the batteries capacity by discharging the battery from fully charged to fully discharged in real life conditions.

 

[Unicorn]

I determine battery usage by using a Grin Satiator to charge. It shows exactly how many amp hours it took to recharge the battery to its previous level. Any decent ebike should show you the operating voltage at any time. Watt hours allow riders with different battery/motor voltages and amp-hour capacity to compare their ebikes. I currently use 58.8V 40Ah lithium (21700 cells) triangle packs with 2352 potential watt-hours per pack (2.35Kw) if charged 100%. The Satiator allows me to pick the charge voltage I want. I charge to 56.8V (2272Wh - 2.27Kw) or approximately 85% battery capacity (34Ah). I never deplete the pack past 20% capacity or 45.4V (8Ah), dramatically extending the number of possible recharge cycles. When I do charge to 100%, I top off the pack just before leaving, which helps not to stress the cells. The battery is the most expensive disposable part on the bike. I know people whose batteries cost more than their entire ebike. Doing everything you can to get the most out of them pays off in the long run.

https://photos.app.goo.gl/6LfYnenuC5LHh5Ry9

Stay safe.