I have become a big fan of electric bikes since my purchase of the Ness Icon in 2018 but one thing that concerned me about an electric bike was how to properly care for the battery throughout the long winter. Hopefully this article will help answer some questions.
Living in Illinois where temperatures can remain below freezing for weeks and where most people have their bikes in storage for months leaves a lot of people wondering whether they should bring their electric bike’s battery inside and/or charge it periodically through the winter.
Most e-bike batteries are lithium-ion and such batteries are fair weather critters, like me. They like it not below freezing and really don’t dig high temperatures in the 90s+.
It’s best to store the battery at or near room temperature but they can be stored in cool dry areas. You just want to check on the battery once in a while. It isn’t necessary to charge it every few weeks. They can go a couple months or more between recharging in ideal storage conditions.
You don’t want to go into your cold garage and plug in the charger thinking you’re doing your bike a favor. For one thing, if it’s extremely cold the battery may not even charge or it will charge very slowly. The battery could actually be damaged this way.
Try to charge the battery when temperatures are above 50 degrees F. It’s also important to state that charging the battery when it’s hot is even worse. A hot battery can become damaged. It’s better for it to be cold than hot.
E-bike batteries are best stored with a remaining charge somewhere between 40-80%, even during ideal temperatures.
If you have a battery indicator on the battery itself, it’s a good idea to check it periodically and if it’s getting too low charge it on a warmer day or bring it inside and bring it up to room temperature before charging.
Don’t leave the battery on the charger thinking that keeping it at full charge will always leave it ready for you to go on a ride or extend the battery life. Lithium-ion batteries do not need to be topped off before you head off and it isn’t necessary to charge up to 100% after every ride. Actually, this will decrease the life of the battery and e-bike batteries aren’t cheap to replace.
If you think you might forget to unplug your charger, which is easy to do, using a wall plug timer is a great idea.
There are also fire resistant bags (see on Amazon) that batteries can be stored in because lithium ion batteries do have a slight fire risk. Remember those hover boards and Samsung Note smartphones catching on fire?
It’s best to store the battery someplace where it will be less of a fire risk, such as in the middle of a garage with nothing flammable around it. Obviously you wouldn’t want to store it under your bed!
Also, whether in warm or colder climates, make sure to have a working smoke alarm and an appropriate fire extinguisher wherever you’re storing your bike’s battery. The risk of fire is small but it’s better to error on the side of caution.
If temperatures really drop, like below zero, it’s best to bring the battery inside and store it in a warmer location.
You can ride your electric bike in cold temperatures but most riders find that range takes a hit. Your bike’s battery will perform the best and the longest when temperatures are closer to room temperature – the upper 60s to mid-70s F.
I hope this answered some of your questions and I hope my bike’s battery has weathered the long winter well because in a few weeks it will be riding weather again and I’m ready to get on the trails!