Electric Bike Batteries Frequently Asked Questions (FAQ)

Electric Bike Batteries FAQ

In this FAQ (Frequently Asked Questions) we answer all the questions ever asked about electric bike batteries. If you have a question about ebike batteries, it should be answered below. But if you don't see an answer, send us notes or add a comment at the end, and we will get an answer for you.

Are electric bike batteries interchangeable?

There are many different kinds of ebike batteries, or more specifically ebike battery cases. Inside the case or housing you will find standard lithium-ion batteries from various well-known brands, including Samsung, LG, and Bosch. Your ebike will be designed to operate at a certain voltage, such as 36V, 48V or 52V, so you need a battery pack and battery management system that matches these voltage.

If the batteries are at the same voltage and have similar mounts and points of electrical connection, then they are probably interchangeable. However, some manufacturers create unique battery cases that only fit their bikes, so while the battery cells in the those cases could be swapped out, the cases themselves are not interchangeable with other bike brands.

Ebike battery explained?

An electric bike battery is really not much different than lithium-ion battery that is in your cell phone. It has the capacity to be charged and hold electric potential in a cell, and discharge this energy to power the motor on your ebike. These batteries have a limited number of charge cycles that can occur before they loose the ability to retain a charge, which is typically 800-1,000 for most modern ebike battery packs.

In the battery pack itself there will be a series of individual battery cells, which are all interconnected and wired to a battery management system (BMS). The BMS makes sure that all the cells have their capacity depleted on a consistent basis, and also maintains the proper voltages with in the system. These battery packs are connected to the ebike controller, which is essentially the brains of your ebike. So when you twist the throttle or turn on the pedal assist system, that sends a signal to the controller, which tells the battery to discharge energy into the motor to power the bike.

Where do I get my electric bike battery replaced?

When your battery no longer holds a charge after several years, you will need to get it replaced (or repacked with new cells). You can go to the bike manufacturer to order a new battery, since most brands carry replacement parts for their models. However, there are also several ebike battery companies in the US that can repack your battery with fresh new cells. These include the Ebike Marketplace and Hi-C Battery.

How are electric bikes charged?

When you get your new ebike, you will see that it comes with a standard battery charger. This electric transformer has one cable that plugs into your ebike battery, and another which plugs into a standard wall outlet. Depending on the capacity of your battery, a full charge may take up to 8 hours to complete. The battery can be charged on or off the bike, and does not present a fire hazard risk. Never the less, we recommend that after you have achieved a full charge, that you unplug the charger.

When to charge an electric bike?

It is a good practice to charge your battery after every ride. It is not necessary to full discharge the battery, nor is it required that the battery be fully charged or topped off. It is important that if you are not going to ride your bike for a period of time, that you give the battery a little workout to keep if from going into hibernation mode. So every two weeks, if you have not ridden your electric bike, we recommend that you turn on the electrical system, and activate the battery by using the throttle for 1-3 minutes. This will keep the battery fresh for the next ride.

Which brand of battery is best for an electric bike?

Many people prefer to get ebike batteries that contain name-brand cells from companies such as LG, Bosch or Samsung. These companies are also known to produce generic versions of their own brand batteries, which may be found on ebike imported from China. In our experience, the batteries that are being produced for ebikes these days are highly reliable and long-lasting. It is hard to distinguish the operational or performance difference between batteries without doing electric bench tests.

What is the strongest ebike battery?

Batteries on ebikes are set to operate a specific voltage, which matches the controller and motor on the bike. These range from 24V on the low end to 52V on the high end, with 48V being the most common voltage. The batteries also have an amp-hour (Ah) rating which determines their capacity, not unlike a gas tank on a car.

Which is the best ebike battery brand?

We do not think there is a substantial difference between battery brands, and it would be difficult to say which is best. Many customers like to know that their ebike batteries contain Samsung cells, as this is a recognized international brand.

Why are the different types of ebike batteries?

Almost all ebike batteries use lithium-ion cells, although their specific chemistry may vary from model to model. When we think of the different types of ebike batteries, most people are considering the two primary specifications, which are operating voltage and amp-hour. There are also differences in the configurations of ebike batteries. For example, on folding ebikes, you often find batteries that are designed to fit inside the frame of the bike, which keeps them hidden from view and protected from the elements. It is also common to find removal ebike batteries on folding ebikes placed behind the seat post. This allows for easy removal for remote charging.

On older ebike designs, you often see the battery pack mounted on top of the downtube. But this type of design is being replaced with batteries that are semi-or fully-integrated into the downtube of the bike frame. By integrating the battery into the frame, you improve the aerodynamic performance of the bike, and often improve its aesthetics.

Some ebike batteries also have a USB port so that you can charge your cell phone off the battery.

Which ebike battery lasts longest?

The capacity of an ebike battery is measured by its amp-hour rating. Most ebikes on the market today have a battery rated at 10.4Ah, 11.6Ah, 14Ah, 21Ah or 25Ah with the higher rating equating to a longer ride per charge. Of course, how long the battery will last per charge also depends on how much you use the motor, road and weather conditions, and other factors. Fat tire electric bikes are usually heavier, and use more motor power, so they can deplete a battery more quickly than other ebikes.

Are all e-bike batteries the same?

No, all ebike batteries are not the same. Ebike batteries vary by their operating voltage and amp-hour (capacity) rating, as well as the configuration of the battery pack and where it fits onto the bike.

How much do electric bike batteries cost?

Electric bike batteries are typically the most expensive component on an ebike. For a typically 48V/11Ah battery, you can expect to pay about $500 for a new or replacement battery. These prices vary by manufacturer, so you should definitely shop around. If you are getting your existing battery packed with new cells, it should cost less than buying a brand new battery. A long range 48V/21Ah battery could cost $700 or more.

Are electric bike batteries removable?

Almost all ebike batteries are removable. This allows you to charge the battery off the bike. It also allows you to remove the battery (and lighten the weight of the bike), if you are going on a ride where you don’t need motor power, or if you want to lift the bike onto your car or truck and want to lighten the load by about 7-10 pounds.

It is also important to protect your ebike battery against extreme weather conditions. So you should definitely remove the battery if you are going to store your bike in a hot truck; and if you live in a cold environment, it is recommended that you remove your battery from a freezing garage or storage area. These protective measures will lengthen the life of your battery.

Can electric bike batteries be repaired?

Electric bike batteries can be repaired. There are several companies in the US that provide testing and repair services for ebike batteries, including Ebike Marketplace and Hi-C Battery. You will typically ship the battery to these companies, and they will test the battery to see what needs to be fixed. They will also be able to replace defective or depleted cells, and check the connections of the battery management system.

Can electric bikes be charged at home?

Yes, ebike batteries are designed to be charged from a standard 110V outlet using the charger provided. Many of these systems also have over-voltage protection, to prevent the battery from over-charging, and fuses to protect sensitive electronics. To be safe, however, we recommend unplugging the battery and charger when you have completed the charge cycle.

Can I replace my electric bike battery key?

Ebike batteries are designed to lock onto your bike during operation. You can contact your ebike brand manufacturer about getting replacement keys for your ebike battery. Otherwise, you could contact a local locksmith if you need to get a new key cut.

How far will an electric bike go?

The range of an ebike depends on a number of factors, including the weight of the rider, the amount of motor usage, riding conditions, and even proper tire inflation. Ebike manufacturers are notorious for over-estimating the range of their products, so we recommend using our Ebike Range Calculator. You should also be able to see your expected range and how much battery capacity is left using your display readout.

How much does it cost to charge the battery?

Charging an ebike battery uses only a few cents worth of electricity. It is the most efficient form of electric transportation, and can save you thousands of dollars a year in expenses.

Can an electric bike battery be charged by pedaling?

Ebikes do not have regenerative braking or other means of charging while riding.

Can electric bikes work without a battery?

Ebikes are like regular bikes and can work without a battery. Most come with gears that can be shifted to help maintain a comfortable tension while pedaling. There is not drag from the motor if you ride with the electronics turned off.

About the Author

Steve M. Appleton, Founder
Really Good Ebikes

With a background in environmental planning, Steve took his passion for sustainable development and started Really Good Ebikes, an online ebike store where he helps people find the best ebikes for their needs, and partners with ebike business entrepreneurs. He is the author of The Beginner's Guide to Ebikes, published on Kindle in 2020. Steve is passionate about animals, and spends part of each day volunteering at the local animal shelter.