Battery Charging Time Calculator

Battery wheel animation

Calculate how long your battery takes to charge based on capacity, voltage, charger amps, and efficiency. Works for eBikes, scooters, and all lithium batteries.

Enter battery capacity in Ah or Wh.
Required only for Ah input. Default 48 V.
Typical chargers: 2A–10A.
Optional. Default is 90%.

This Charging Time Calculator helps you determine exactly how long your eBike or lithium battery will take to reach a full charge. By entering capacity, voltage, charger amps, and efficiency, you get an accurate estimate of the total charging duration.

How the Charging Time Calculator Works

The formula used is:

Charging Time = Battery Capacity ÷ Charger Output × Efficiency Factor

If your battery is entered in Ah, the tool automatically converts it to Wh using voltage for a precise result.

Typical Charging Times

  • 48V 10Ah battery with 2A charger → ~5–6 hours
  • 48V 15Ah battery with 3A charger → ~5 hours
  • 52V 20Ah battery with 5A charger → ~4–4.5 hours

Factors That Affect Charging Time

  • Charger amperage (higher amps = faster charging)
  • Battery capacity (larger packs take longer)
  • Charger efficiency (low efficiency = slower charging)
  • Temperature (charging slows in cold weather)

Charging Safety Tips

  • Avoid charging immediately after riding.
  • Never charge near flammable objects.
  • Use only the recommended charger for your battery.
  • Stop charging at 80–90% for maximum battery longevity.

Frequently Asked Questions

Q: Does a higher amp charger reduce charging time?
A: Yes. Higher current (A) means faster charging, but using too high amperage can shorten battery lifespan.
Q: Does charging efficiency matter?
A: Yes. All chargers lose some energy as heat. Typical efficiency is 85–95%.
Q: Can I charge my battery overnight?
A: While possible, it's safer to avoid overnight charging unless your charger has built-in protection.
Q: Why does charging slow down at the end?
A: Lithium batteries use CC/CV charging; the final 10–20% is slower to protect cell health.