How to Care for Your E-Bike's Battery

By Jonathon Weber

Five or so years ago, as e-bikes were just starting to pick up steam, my partner and I invested in an e-bike for her to commute on in San Diego, California, where we lived at the time. She loved it! And best of all, it meant that our car didn’t move on most weekdays. 

But a few months later, she changed jobs. The commute became less bikeable, and the e-bike sat unused. Months later, even after several hours of charging, the battery wouldn’t deliver any power. It was dead and replacing it was going to cost hundreds of dollars. 

Little did we know, e-bike batteries need special attention in order to keep powering you to work and the grocery store—and we didn’t hold up our end of the bargain. 

E-bikes are rapidly gaining popularity and for good reason! Early studies have shown that e-bikes help folks replace car trips and reduce their transportation emissions, all while getting exercise and feeling connected to the world around them. And for folks who have trouble powering a conventional bicycle, e-bikes have been a way to re-start or continue their bicycle lifestyle. 

But the ease of riding an e-bike comes with some extra care required on the part of the owner. That’s because most e-bikes are powered by lithium-ion batteries. These can quickly lose capacity (and therefore range) or even die prematurely if not treated properly.  We reached out to a handful of manufacturers of e-bike batteries and e-bikes—including Bosch, Shimano, Rad Power Bikes, and Specialized—for their take on battery care and maintenance. It’s very likely that your bike’s battery requires similar care, but it’s a good idea to check with the bike shop that sold you the bike or contact the manufacturer directly for specific care guidelines.

Here are four key takeaways for general e-bike battery care:

- When you get home, wipe down your battery if it’s wet or dirty, and bring it inside. Store it in a dry place between 50 and 68 degrees, out of direct sunlight. (Example: A dry basement!)

- For long-term (2+ weeks) storage, keep your battery at 60-75% charge. Check it periodically to maintain this level. Never allow your battery to sit with 0% or low charge levels.

- Never charge a cold battery! Allow it to warm to 50 to 68 degrees before plugging in. 

- Leave your battery installed to protect the electrical connections during short-term outdoor parking at work or the grocery store. It’s always best to store your bike inside when possible, but covered outdoor parking is much better than uncovered outdoor parking. If you have to leave your e-bike outside uncovered for long periods of time, especially during the winter, consider making or purchasing a waterproof cover for the battery port so that the connections are protected while you bring the battery inside to keep it warm and protected.

Follow those tips, and any others specific to your bike’s battery, and you will have done your part in ensuring that your battery lives a long, healthy life, and helps get you where you’re going for many miles to come.

Did you know that many Vermont utilities are offering rebates on e-bikes? Learn more here.