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Battery Charging Time Calculator

Calculate how long your e-bike, scooter or motorcycle battery takes to charge from any level, with any charger.

Only know amp-hours? Wh = V × Ah.

Printed on the charger as "Output", for example 42 V ⎓ 2 A.

Charging time

–

Ready at about – if you plug in now.

–fast phase (to 80%)
–slow top-up phase (80 to 100%)
–charging power
–charge rate

Tip: stopping at 80% saves time and is gentler on the battery for everyday use.

How the battery charging time calculator works

How long does it take to charge my battery? With a standard 2 A charger, a 500 Wh (36 V) battery takes about 6 to 7 hours from empty. A 4 A fast charger cuts that to roughly 3 to 4 hours. Charging from 20% to 80% is much quicker than a full 0 to 100% charge.

  1. Charger power (W) = charger output current (A) × battery nominal voltage (V).
  2. Time to 80% ≈ energy needed ÷ charger power ÷ efficiency. Lithium-ion chargers run at constant current up to about 80%.
  3. The last 20% is slower (the constant-voltage phase), so we add a taper: about 1.5× the constant-current rate for that final part.

Results are estimates to help you plan and compare. Always follow your manufacturer's specifications, especially for charging, tire pressure and load limits. Found a problem with this tool? Let us know.

Charge time questions, answered

How long does an e-bike battery take to charge?

With a standard 2 A charger, a 500 Wh (36 V) battery takes about 6 to 7 hours from empty. A 4 A fast charger cuts that to roughly 3 to 4 hours. Charging from 20% to 80% is much quicker than a full 0 to 100% charge.

Does fast charging damage the battery?

Moderate fast charging, around 0.5C or less, has little effect on a quality battery. Frequent very fast charging, high heat and routinely charging to 100% speed up wear. For daily use, charging to 80 to 90% is the best way to extend battery life.

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