Why Do Ebike Batteries Die? (Does It Need Replacing?)

  • By: Kevinsmak
  • Date: January 12, 2023
  • Time to read: 6 min.
Affiliate Disclaimer

As an affiliate, we earn from qualifying purchases. We get commissions for purchases made through links in this post.

Improvements in e-bike technology have been dramatic in recent years. Batteries are better, motors are stronger, and the design as a whole has advanced.

One aspect of e-bikes that hasn’t altered much, though, is the battery’s longevity. Any regular user of an electric bicycle is aware of the inevitable demise of their battery. What could be the root problem, and does it require replacement?

Because of a lack of care, the batteries in electric bikes eventually die. An ebike battery can die from several causes, including poor charging, a lack of use, or improper storage. Battery death can also occur if you routinely deplete the battery to zero and then charge it.

Why Do Ebike Batteries Die?

Here are a few of the most common causes of an ebike battery’s early demise:

Battery Capacity Degradation

Lithium-ion batteries have several performance benefits compared to nickel-based batteries that were once used. However, reducing the battery’s total lifespan is an issue affecting all batteries.

Your battery gradually loses a tiny portion of its total capacity after each full charge cycle. Although this minor amount of capacity loss is negligible, it mounts up after hundreds or thousands of full charge cycles.

Most electric bike batteries are rated for the number of charge cycles needed to lower their capacity to 80%. In other words, your battery will contain 20% less energy than the first time you used an eBike battery after you have fully discharged and recharged it a specific number of times.

Although the number of cycles needed to deteriorate a battery varies completely, it usually takes 800 to 1,000 full charge cycles. We also want to note that it’s a full charge cycle, something you’ll rarely do with your battery.

It can take 1,500–2,000 charge cycles if you recharge it from 50% to 100% before your battery is down to 80% capacity.

Improper Charging

The charging method also affects the battery’s durability. Always charge your bike’s battery with the charger it came with, as it was designed for your battery’s exact voltage and current needs.

Take care not to overcharge or undercharge your battery. Overcharging can cause cellular damage, which can shorten one’s life span.

Undercharging is another potential cause of cell damage and battery instability.

Batteries should be charged when they have dropped to around 20% of their capacity. Therefore, its useful life is extended.

Storing your battery in a hot car or a cold basement will shorten its life.

Improper Storage

The cells in your battery might also be damaged if you keep it at an extremely high or low temperature. It is recommended that batteries be stored inside during extremely cold winters.

Direct sunlight has been shown to hasten the degradation of battery cells. Thus keeping your battery in such an environment is not recommended. Your battery will last longer if kept in a cold, dark place.

Regularly Fully Discharging the Battery

Repeatedly letting a battery die down to zero before charging it is a bad idea. It can limit the battery’s life and perhaps destroy the cells if you do this.

It is recommended that you do not completely discharge your battery. If you must drain it totally, recharge it as soon as possible.

Damaged or Broken BMS

There are many functions carried out by the battery management system (BMS) in every eBike battery. The BMS aids in the secure and balanced charging or discharging of your eBike’s battery when it is connected to a charger or motor.

If your battery ever gets damaged, the BMS will prevent it from shorting out and damaging your charger or motor, reducing the risk of a fire or explosion.

Your battery’s BMS has likely failed if it abruptly stops working after only a few charging cycles for no apparent reason. Following correct charging practices, maintaining your battery in ideal conditions, and limiting the amount of physical stress and strain it endures will protect the BMS from failure.

However, on rare occasions the BMS may suddenly stop functioning normally. Now is the time to contact the e-bike or battery maker and find out if a replacement battery is covered by the warranty.

How to Tell When an Ebike Better Needs Replacing

The most obvious sign that you need a new ebike battery is when the one you have stops holding a charge. If your bike only goes half as far as it used to on a single charge or takes twice as long to recharge, those could also be signs that the battery is losing capacity.

Other signs that you may need a new battery include:

Battery Swell or Leak

When batteries bloat or leak, it’s time to replace them. A dead battery is an indication that your device needs a new battery.

Your ebike will not function properly if the battery is damaged or fails.

Strange Noises

Strange noises coming from the battery while it’s charging or in use can be caused by a number of things, including a damaged cell or loose connection. If you hear any strange noises coming from your battery, it’s best to take it to a certified ebike technician to have it checked out.

Ebike Won’t Turn On

Many things, including a dead battery, could be to blame if your electric bike won’t power on. If your electric bike is acting up, you should have it serviced by a trained professional.

Tips To Prolong the Life of Your Bike Battery

Unfortunately, batteries wear down over time no matter how well you treat them. However, you may extend the life of your battery and maximize its performance by taking certain measures.

Here are a few pointers:

  1. Consider Investing in a Better ChargerOne of the greatest methods to keep your battery running for as long as possible is to use a charger of higher quality.
  2. Beware of Extreme Conditions: Both extremely high and low temperatures can harm your battery.
  3. Keeping your battery in the correct charging condition will increase its lifespan.

If you want to keep your batteries in good shape, it’s a good idea to check the connections between it and the bike on a regular basis.

Ebike Battery FAQs

Final Thoughts

Damage to the ebike battery, incorrect storage, or capacity loss is all potential causes of an ebike’s battery demise. In the event that you suspect your ebike’s battery needs to be replaced, it is recommended that you seek the assistance of a trained ebike technician.

When going on long trips for days, you can always take a generator with you to charge the ebike.


Please be careful and use at your own risk
None of the authors, contributors, administrators, or anyone else connected with RCRideOnCars.com, in any way whatsoever, can be responsible for your use of the information contained in or linked from these web pages.