Ebike battery duration

The way you use your battery can considerably increase its duration and even its performance.

Last update: 25/07/2023

Correctly using your battery to extend its life

Manufacturers often specify ebikes battery duration as ranging from 500 to 1000 recharge cycles for a capacity of at least 70 %. This matches what most electric car battery manufacturers guarantee, about 180,000 km or five years before the battery loses more than 30 % of its capacity. Nevertheless, here are some tips to extend our battery life.

I explain in detail in another post how to charge your battery to increase its duration (for instance, avoid charging it beyond 85%. They have no memory effect whatsoever, so no need to completely discharge them before charging. On the contrary, it seems that discharging battery cells to less than 20% causes a certain stress, deminishing their long term duration.

Try to avoid overheating and overcooling in general. A battery ideal working temperature is around 20 °C. Here’s what can bring the temperature well above this level; nevertheless, a battery cover can effectively attenuate thermal shocks:

• Parking your ebike in the sun. Since your battery is normally black, after a few minutes of exposure to the sun, it can easily exceed 40 °C, even more if it was already warm after a ride. I would prefer a white battery, like some Bosch ones, even if it would require more frequent cleaning, because of exhaust pipes smoke.
• Submitting your battery to a prolonged effort, for instance biking on a long, steep climb. I remember having a bike with two batteries. On long climbs, every 10 minutes I switched from one battery to the other. When I switched back, the battery display showed a higher level of charge, since I had allowed it to cool down a bit.
• Biking in the sun can also considerably heat your battery. And frequent usage with temperatures below zero can wear it off faster.
• If you have ridden in cold weather, wait until your battery is warm, having been stored in a warm place, before you start charging it.
• Don’t use low assistance modes when riding in cold weather. The higher the assistance level, the better the battery will warm up to reach ideal working temperature.
• Regular pedalling rhythm, without pace changes helps the motor save energy.
• Shift to a lower gear, since the optimal pedalling frequence, allowing the motor to save energy, is 80 revolutions per minute.
• Ride on optimal tire pressure, clean and lubricate your chain.
• In the winter, keep your battery warm with the battery cover, if you don’t want to buy one, you can make one yourself. Cut the sleeve of a worn off winter jacket, then glue some straps to it, in order to handily set it on and off your battery.
• Upon starting, use a lower level of assistance, in order to let your battery warm up gradually and without abrupt demand of energy that can stress it. After a couple of hundred meters you can switch to a higher level of assistance.

Ebike Trek Domane ascent test

Moderate energy consumption

1,000 cycles of recharge, amounting at 25,000 to 30,000 km, is the average estimation for the duration of a li-ion battery. Personally, I rode 6,400 km with a 300 Wh battery, purchased in March 2014. I just had it checked by an ebike mechanic. The Bosch measuring device stated that my battery has still got 78 % capacity. Nevertheless, I was appalled to know that a friend of mine has still got 80 % of capacity on his battery after five years and 28,000 km. The difference, is that I always ride with maximum assistance, climbing every day at least 300 m, whereas my friend rides on flat territory, with minimum or nearly minimum assistance.

Properly store your battery

A garage or even a cellar, if not too moist, would be okay, since extremely low or high temperatures can damage your battery. Normally, a stored battery loses between 5 % and 10 % of its capacity every 12 months. Storing a battery completely discharged or completely charged can also decrease its capacity, more seriously if it’s completely discharged.

The advice I gave in this article can be applied also to other kinds of lithium-ion batteries.

Take good care of your battery, and it’ll do the same with your biking.

Find more ebike tips here.

Updated on 03/16/2023