The battery is the most expensive component of an electric bike and the one that most determines how you can use it day to day. Understanding three figures (volts, amp-hours and watt-hours) lets you compare models and extend its life by several years.
V, Ah and Wh: the figure that matters
A battery's real capacity is measured in watt-hours (Wh) = volts × amp-hours. A 48 V, 15 Ah battery has 720 Wh. The more Wh, the more kilometres. If a manufacturer only states the Ah, multiply by the voltage to compare.
Real-world range by capacity
| Battery | Estimated real-world range | Example in our range |
|---|---|---|
| 360 Wh | ≈ 26–36 km | ENGWE Zip |
| 468 Wh | ≈ 33–47 km | DUOTTS C29Lite |
| 624–648 Wh | ≈ 45–64 km | ENGWE EP-2 Boost |
| 720 Wh | ≈ 51–72 km | ENGWE O20 Boost, DUOTTS C29 |
| 864–960 Wh | ≈ 65–91 km | DUOTTS F26Lite, DUOTTS F26 |
| 1,800 Wh | ≈ 129–180 km | DUOTTS C29-K 1,800 Wh |
Prices are indicative at the time of publication (September 2026); the current price is shown on each product page. "Estimated real-world range" is NovoDix's own calculation: we divide the battery capacity by a consumption of 10–14 Wh/km, typical for mixed use with medium assistance, an adult weighing 75–85 kg and terrain with some hills. The figure claimed by the manufacturer is measured under ideal conditions.
How much it costs to charge
| Battery | Cost of a full charge | Cost per 100 km |
|---|---|---|
| 360 Wh | ≈ €0.06–0.08 | ≈ €0.17–0.31 |
| 720 Wh | ≈ €0.12–0.16 | ≈ €0.17–0.31 |
| 960 Wh | ≈ €0.16–0.21 | ≈ €0.17–0.31 |
NovoDix's own calculations, using electricity prices of €0.15–0.20/kWh and 10% charger losses. Bike prices are indicative as of September 2026.
How long a battery lasts
The lithium batteries in electric bikes typically withstand 500 to 1,000 full cycles before dropping to 70–80% of their capacity. With a charge every 2–3 days, that's 4–7 years of use. It doesn't lose range all at once: it loses it gradually.
7 care tips that extend its life
- Don't leave it for weeks at 0% or 100%: store it at 40–60%.
- Don't charge it below freezing or straight after heavy use; wait for it to cool down.
- Avoid direct sunlight and a car boot in summer.
- Use the original charger or one with the same voltage.
- In winter, store it indoors.
- Partial charges don't harm it: there's no need to run it flat.
- Clean the contacts and don't pressure-wash it.
When to replace it
If the range has dropped to less than 60–70% of the original, or the battery gets hot or swells, it's time to replace it. NovoDix has replacement batteries and chargers for ENGWE and DUOTTS. A second battery can also double your range on long rides.
Frequently asked questions
How many years does an electric bike battery last?
Between 4 and 7 years of regular use, or 500 to 1,000 full cycles, depending on care and climate.
How much does it cost to charge an electric bike?
Between €0.06 and €0.21 per full charge depending on capacity; about €0.20–0.30 per 100 km.
Can you leave an electric bike charging overnight?
Chargers cut off at 100%, but to prolong battery life it is better to unplug it when it finishes and not leave it at 100% for weeks.
More guides
- Best Folding Electric Bikes 2026
- Cheap Electric Bikes
- ENGWE vs DUOTTS
- Electric Bike for Commuting: What to Choose and What You Save
- E-Bike Battery: Lifespan, Charging Cost and Care
- Mid-Drive or Hub Motor: Which Is Better on an E-Bike?
- Electric Bikes for Seniors: Step-Through Frames, Safety, Models
- Electric Bikes for Tall Riders or Riders Over 100 kg