Batteries serve as the soul of electric bikes. They are very critical components in an e-bike as they play a significant role in the overall performance. But why is it so?
It is because the power source of an e-bike is the battery. It converts electrical energy into mechanical energy. Hence assisting the rider in moving the bike forward.
If we talk about the performance of the ebike, it majorly depends on the battery capacity. A high-quality battery with high voltage can deliver a more responsive and powerful riding experience.
Therefore, having the right size ebike battery with good quality is crucial for an ebike.
If you are planning to replace a battery on your ebike or convert your pedaled bike to electric, this comprehensive blog on ebike battery buying guide will help you choose the best battery for your electric bike.
The purpose of the blog is to explain every detail and smallest of the questions that you might be having while buying an electric bike battery. So stick around till the end to know how to choose ebike battery and what things to look out for before choosing an electric bike battery.
Let’s move ahead with the hope that you won’t need to jump on other resources. Because this is designed to help you in the best ways possible.
Understanding Electric Bike Batteries
We all know what a battery is! Basically, It is a combination of multiple cells which are connected in a parallel way or series way.
Before moving towards the electric bike battery buying guide, you must be aware of the basic terms of batteries, how they are important, how many types of ebike batteries are there, the terminologies, and everything.
So let’s go ahead and try to understand them:
Basic terms in ebike batteries explained
Let’s clear out all the terms that you will potentially encounter further.
Voltage (V): It refers to the electrical potential difference of the force that helps the bike in moving ahead. In simple words, it is the force that makes the bike go fast or slow. Well, it is the strength of the battery. It determines how fast the ebike can go.
Capacity (Ah): It is the Ah in the battery. Ah stands for ampere-hour. But what does that mean? It means the amount of energy the battery can hold. More capacity means the battery can hold more charge and will take longer to discharge.
Watt-hours: It is the multiplication of battery volts to the battery’s Ah (capacity) which indicates how much wattage (electric power) a battery can supply in an hour, that’s why is it called watt-hours. See the formula below,
Watt hours = Voltage (V) x Ampere hour (Ah)
Range: The distance covered by the bike on a single charge. For eg. a 36v 10Ah battery on a 250w ebike provides around 25-40 miles. Well, it depends on many factors (discussed below).
Cycle life: There is a certain period until which the battery puts on its best self. Because after that it starts to lose its capacity. This means it requires more frequent charging than before. The number of times a battery can be charged and discharged before it starts losing its capacity is the cycle life.
Charging time: The amount of time it takes for a battery to be 100% itself is the charging time. Faster charging means less time wasted! (Note: You should always charge your ebike battery to 80% only to maintain and prolong the battery life).
Removability: Sometimes the batteries are removed for charging purposes. Removability refers to the taking off of the batteries for this kind of activity.
These were the terms that you could encounter. Now let us move to the types of batteries which are available in the market for electric bikes.
Types of Batteries in Electric Bikes
There are majorly three types of batteries used in e-bikes. They are listed below, Let’s see them in depth:
1. Lithium-ion (Li-ion) batteries
These are the most popular batteries in the market because they offer a higher energy density than other types of batteries which means that they can store higher energy in them.
With this high energy, they are also very light in weight and small in packaging. As well as their life cycle is long and they offer high power output and efficiency.
Lithium-ion batteries are costly but Yes! They have a low self-discharge rate and are considered the best choice in batteries. Ebikes with lithium-ion batteries are the best. Keep reading to learn more about the advantages and disadvantages of lithium-ion batteries.
2. Lithium polymer (LiPo) batteries
They are similar to lithium-ion batteries in terms of benefits. But in addition to that they are more flexible. This means they are packaged in very flexible pouches rather than rigid cylindrical cells.
They are mostly known for their compact size and flexibility to fit different bikes. They are usually used in smaller and more compact bike models.
3. Nickel-metal hydride (NiMH) batteries
These batteries were usually used in the past. Through the upcoming use of lithium-ion batteries and lithium polymer, these batteries lost their use compared to before.
They offer a decent energy density and are cheaper compared to the batteries mentioned above. They are generally very heavy and overweight. This affects the overall weight of the bike as well.
Besides these, their power output is also low compared to lithium batteries and has a shorter life cycle. All of these factors in turn affect the performance and efficiency of the bike.
Let’s Understand Battery Capacity (WH) & Range
Battery capacity is usually measured in watt-hours. It is an essential factor in determining the range of an electric bike. But what are watt-hour and range?
Well, a watt-hour is the power needed by the battery in an hour to function perfectly. Watt-hour and ampere-hour are interrelated. By multiplying the volts and the ampere-hour we get the watt-hour.
Watt-hours = Volts x AH
If the voltage differs, two batteries with the same Ah, watt-hour will also differ. And similarly, if the Ah differs, again watt-hour will differ.
Then, What is the range? It is the distance an ebike can travel on a single charge. Here is the formula to calculate the range of an ebike.
Estimated Range = Battery’s WH / WH consumed per mile
You already know what a battery’s WH is! Let’s understand Wh consumer per mile. When an ebike runs, it consumes battery power which is measured in Watt-hours (Wh).
Each electric bike has different motor wattages which means they will consume different WH to cover 1 mile. Generally, an ebike consumes around 10-15 wh per mile when ridden at a normal speed. And consumes around 20-30 wh when ridden at fast speed.
So we calculate both scenarios as we have to calculate the estimated range of the ebike battery.
Let’s assume: we have a 500-watt ebike battery paired with a 500w electric bike. It consumes 10Wh per mile at normal speed & 20Wh per mile at fast speed.
Estimated distance at normal speed = 500 Wh / 10 wh per mile = 50 miles
Estimated distance at fast speed = 500 Wh / 20 wh per mile = 25 miles
Hence the estimated range is 25-50 miles.
After having understood the basic concepts of battery capacity and range, let us look at some of the factors that affect the range.
- Battery capacity: The very first is the battery capacity i.e., Watt-hours. The higher the capacity of the bike, the longer the range is. This is possible because higher-capacity batteries can store larger energy in them.
- Riding conditions: The riding conditions such as terrain or wind resistance or hilly areas affect the range a lot. You will be able to cover a longer range in smooth terrain. Whereas in hilly terrains, the range covered will be quite less as your bike will consume more battery power.
- Speed: This is obvious isn’t it? Ebike speed and range have an inverse relation. Higher-speed ebikes consume more battery power and hence give less range & vice-versa. So, if you want to cover longer distances, ride at normal speed and use the pedal assist feature instead of throttle mode in your ebike.
- Weight: Weight too contributes a lot when it comes to range. How you may ask. When there is more weight on the bike, the energy consumption of the battery increases hence it results in shorter ranges. So you can avoid wearing unnecessary or heavy accessories to cover more range.
- Rider’s input: Even in an electric bike, the rider has a lot to contribute. From pedaling to posture, range depends a lot on the rider too. If you mostly use throttle, your range will reduce. It’s better to use the pedal assist feature for better range & speed.
By considering all these factors the range of an e-bike can be enhanced. Also based on the battery’s watt-hour and capacity, riders will be able to estimate the range of their electric bike. And this part is very important when you don’t know how to choose battery for electric bike.
Battery Voltage and Power Considerations
The voltage of an e-bike battery directly influences the power output. Voltage is very crucial when it comes to a bike’s performance. Hence understanding how it happens is essential to match the battery voltage to the bike’s specification.
Higher voltage means a greater electrical potential difference. This results in increased power and performance. Now, there are some ways in which voltage affects the performance of the bike. Here are some of them:
1. Motor performance
The motor of an e-bike is designed in such a way that they operate at a specific voltage range. When the battery voltage matches the motor’s voltage specifications it ensures optimal performance and efficiency.
When the bike has higher voltage batteries it delivers more power to the motor which results in faster acceleration but is not good for the motor’s health.
2. Torque and speed
Voltage directly affects the torque of the motor. Hence, a high-voltage battery offers more torque. But how does torque affect the performance of the bike?
Ebikes with higher torque accelerate faster making it easier for the bike to achieve high speed. This enables smoother and more effortless rides, especially in rough and hilly terrain.
3. Battery compatibility
As I mentioned earlier, ebikes are made in such a way that they work with specific voltage ranges. Hence, matching the battery voltage to the specifications of an e-bike ensures the compatibility and safe operation of electric bikes.
From fitting the battery in the racks of the bike to the correct voltage combinations, compatibility goes a long way. When avoided they can lead to a lot of damage. They can reduce the performance and there is a potential that the inner components can be damaged as well.
Therefore, It is very important to match the battery voltage according to the specifications provided by the manufacturer. When purchasing a replacement or during upgrades we must ensure the voltage matches the previous one.
4. Battery life
When we use a battery that has a correct voltage it helps optimize the lifespan and durability of both the battery and the e-bike’s electrical system. Using batteries that have a higher or lower voltage range than recommended, often leads to the destruction of the inner components of the bikes.
Higher voltage means heavier battery and these heavy batteries enhance the weight of the bikes. And we already know how heavy batteries negatively impact the riding experience. Similarly, a lower voltage battery would not support the bike either and would result in damage as well.
Overall, battery voltage plays a very crucial role when it comes to compatibility and performance (speed). One must match it with the ebike motor’s voltage. When it is not matched, the bike faces a lot of problems like compatibility issues, motor performance, etc.
How to Choose Ebike Battery?
Selecting the right battery for your electric bike is very crucial to ensure optimal performance. Here are some points that you should keep in mind while buying or replacing an electric bike battery.
1. Assess your needs & usage (Commuting, off-road, or leisure riding)
One of the most important factors is how long you are going to travel every day on your ebike. Evaluate it from the very beginning. Know how & why you are going to ride the bike and then move forward to select the right battery for your electric bike.
Will you be using it for off-road adventures or daily use? This would determine the usage and help you identify the type of battery based on the capacity requirements.
For example, if you are going to use it for adventures, then the distance covered, and the terrain will differ and it would require a higher capacity (WH) battery to fulfill the requirements and give you a smooth riding experience.
And on the other hand, the capacity would be much less when used for daily commutes. So decide your purpose in the first step.
2. Distance (Range) and terrain considerations
The range is the distance covered by the bike on a single charge. This range would differ on a lot of factors like the capacity of the battery, motor efficiency, terrain, overall weight on the bike, etc.
Determine the minimum range you would need to comfortably complete a typical ride on a single charge. The battery capacity is directly related to the weight of the battery (a higher Ah battery has more weight) and hence you will need to find a balance between the range and the added weight of the battery.
Also, you must consider the terrain that you would be mostly traveling on.
For instance, if the bike is for off-road adventures then the terrain would be rough and hilly and it would require you greater effort to travel and ride the bike. This puts an extra force on the battery hence it would require more capacity.
Whereas, if it is for daily use, you would be encountering smooth roads and hence the capacity would be less.
So we can say that your minimum range (distance) is one of the most important factors in the electric bike battery selection guide.
3. Battery voltage and controller compatibility
Once you are done with the above steps, check whether your battery voltage is compatible with the controller. The voltage of the e-bike must align with the bike’s motor and controller.
Most e-bikes operate on 36V, 48V, and 52V systems. Using an incompatible voltage can lead to damage to the controller and the motor. This would lead to poor performance.
4. The battery must have a BMS (Very Important)
BMS stands for the battery management system. It is a critical component of the battery because it ensures protection. It protects the battery from getting overcharged, over-discharging, and overheating.
Hence, It becomes important for us to choose a reliable battery management system to safeguard the investment that we are making in choosing the battery for the ebike.
5. Battery voltage compatibility with the Motor
When we calculate the watt-hour for our ebike battery, we already measure the voltage that would go with the bike. And measure it in such a way that the battery turns to be in alignment with the power of the bike.
It means the voltage rating on the battery must align with the voltage rating on the motor. This ensures the compatibility between the battery and the bike. Compatibility in turn ensures that the bike achieves the best performance and longevity.
6. Physical dimensions (size, weight & shape)
As mentioned previously, the physical dimensions also affect the ebike battery in a lot of ways. The bigger the size of the bike, the greater the weight will be. This in turn would require more energy and hence greater capacity batteries would go with these kinds of ebikes.
On the other hand the smaller the bike, the lesser the weight will be and hence a lesser-capacity bike would do just fine! The ebike shape also plays a crucial role when choosing an ebike battery.
Let’s know how?
When the shape is suited for aerodynamics, the speed of the bike increases with the wind flow and the battery suffers less. Poor shape and weight distribution affect the riding experience as well as the stability of the bike and the rider.
7. Budget (price) considerations
Set a budget after looking at your needs before going to buy the battery. Battery prices usually vary because of capacity, brand, and the technology used. One important point, as important as your budget is here, it is equally important for you to consider the long-term cost as well.
For example, higher-capacity batteries may be costlier but they provide better value in the longer run. It is always best to consult the manufacturer or professionals while going on to select a battery for your electric bike.
Apart from these, Read the reviews of what other people have said about the battery that you are going to purchase. Also, check the specifications of the bike they have bought the battery for.
By carefully assessing the needs and the above-mentioned factors and your budget, you will be very well-equipped in selecting the right battery for your electric bike. Keep reading to learn more about how to choose battery for ebike.
Key Factors to Consider When Buying an Ebike Battery
There is so much when it comes to buying a battery for your electric bike. What are the points to consider before buying them? Do not worry, we have got you covered!
Here are 7 key factors you can consider before making a purchase of an electric bike battery:
1. Battery life and longevity
We have already discussed battery life in the terms and terminologies section. the lifespan of a battery should also be considered when buying it. The battery life is highly affected by the charge cycles (refers to the number of times the battery can be charged throughout its life).
The average lifespan of a lithium-ion battery, which is mostly used these days, is 500-1000 charge cycles (read the source). Also, the battery management system should be taken into consideration too. This will ensure the overall safety of the bike and hence extends the battery’s lifespan.
2. Battery weight
The weight of the battery has a significant impact on the bike. A battery with greater weight disturbs the overall weight of the bike which affects the control and stability of the bike.
This may prove fatal to the rider and is prone to mini accidents too. That’s why It is very crucial to consider the weight distribution and how it will impact the riding experience.
Usually, the higher capacity batteries are the heaviest. Try to find a balance and you will be good to go.
3. Battery mounting options
The ebike batteries can be mounted on the frame or integrated into the frame itself. Frame-mounted batteries are mostly removable with keys. This makes it easier to charge inside the home and replace them.
Whereas, Integrated batteries are fixed into the frame. It gives them a sleeker and more streamlined appearance. Also, note that this is entirely a personal choice and the choice does not have a very large impact on both the battery and the bike.
4. Charging time and compatibility
Consider the ebike battery charging time and compatibility with the charger. Make sure your battery doesn’t take long hours (8-10 hours) to charge. Also, check the compatibility with the fast chargers. Less charging time means time SAVED and it is very efficient this way.
Removable batteries can be charged separately while integrated batteries may require the entire bike to be connected with a charger. The battery you choose must be compatible with your ebike, it should fit the rack it is supposed to be in.
5. Warranty and customer support
A reliable warranty and customer support are the keys before buying literally any appliance. This gives a sense of security to the buyer and also builds trust between the manufacturer and the customer.
This applies to buying the battery for your bike too. A good warranty provides coverage for manufacturing defects and premature battery failure. In addition to this, responsive customer support is very valuable in case you encounter any issues with your ebike battery or want your questions answered related to the battery.
6. Battery Certification
Look for batteries that have undergone the certification processes. Go for the UL2849 certification if you are in the USA. This certification ensures the battery is meeting specific safety and performance standards.
7. Battery Performance
The battery performance can vary largely depending on weight, terrain, and riding styles. Greater or better performance can be largely seen in smoother terrains and with lesser weight on ebike.
On hilly terrains and with more weight, the battery performance will drop down as it would require more energy. These specific requirements are hence required to be specified before even going to purchase a battery.
You should also try to avoid wearing heavy or unnecessary accessories while riding the bike. This reduces the bike weight which puts less effect on the battery hence making the ride smoother.
By considering these factors and conducting your research you will be able to select a battery that is perfect for your e-bike. If not, you can always consult an expert or the manufacturer.
5 Tips for Maintaining and Extending Electric Bike Battery Life
There are a few ways we can follow to maintain the battery of our e-bike. Following these, we can also extend the battery life. Here are 5 ways you can start taking care of your battery right from today:
1. Proper charging practices
This is one of the most important yet very underrated. People do not pay attention to this and this results in a lot of loss. Hence, it makes sense to follow proper charging practices.
First and the foremost thing that you need to stop doing right now is overcharging. The reason is overcharging leads to overheating which reduces the lifespan of the battery. So, keep track of the charging, and as soon as you see it is fully charged. Remove it.
The second thing is not to let your battery run completely out of charge. When you see it is on 20 or 30% put it on charge. When you keep your battery empty for a longer time, it leads to irreversible capacity loss.
2. Avoid extreme temperatures
Avoid them as much as you can. Extreme temperatures tend to speed up the chemical reactions in the battery. This results in capacity loss and decreased cycle life i.e.dead ebike battery.
If the conditions are unavoidable you can either try not to ride your bike or go with it anyways. But when you are using it anyways you will have to replace your battery after some time.
3. Optimal discharge and usage
As said earlier, deep battery discharges put stress on the batteries. Always keep your battery charged in the range of 20 to 50%, it ensures good health of the battery.
Also, you must avoid putting a lot of weight on your bike. Because it makes the bike heavy which in turn requires more energy affecting the bike negatively. In addition to this, you can maintain a moderate speed i.e., neither too high nor too low abruptly.
4. Regular maintenance
Take time to inspect and clean your battery and e-bike. Check for signs of physical damage or any loose connections, or anything unusual. When cleaning the e-bike make sure you are not affecting any of the electrical components with water.
Try to wipe the components off with a semi-wet cloth. While checking if you find anything unusual directly contact the manufacturer or qualified professionals for assistance.
5. Storage and off-season care
When the off seasons come, which typically means that your bike would not be much used. These seasons could be freezing winter and scorching summer or even too much rainfall.
During this period, you are advised not to use your ebike because of the damage concerns. Now when putting the bikes away for a longer time, you need to be extra careful.
Charge it for at least 50% capacity to prevent self-discharge while also avoiding overcharging. Keep it in a cool area away from direct sunlight. You can also opt to detach the battery completely from the bike to ensure that it stays well enough.
Conclusion on the Ebike Battery Buying Guide
This electric bike battery buying guide was intended to solve all the problems that you might face when choosing a battery for your electric bike. Keeping all the general queries in mind we have tried to solve all of them and covered each important topic.
From the right size to the factors you need to keep in mind everything is there in detail. Make sure you are choosing a battery that is compatible with your e-bike or else nothing would make sense.
If you are facing any problem consult the manufacturer or an expert in this field because the right size battery is very important for your bike.
In case you have any other questions on how to choose ebike battery, you may drop them down for us to answer.
Frequently Asked Questions (FAQs)
Q1. What is a good battery capacity for eBike?
Battery capacity means Amp-hours (Ah) which shows how much current it can store and it depends upon the ebike wattage. For a 250w ebike, a 10Ah battery capacity is enough as it can easily cover around 20-40 miles on a single charge. Increase the Ah if you have a higher-wattage electric bike.
Q2. Will a higher voltage battery make my eBike faster?
Yes, a higher voltage battery can make your ebike faster as I have already mentioned above that voltage determines the performance & speed of the ebike. So, You can pair your ebike with a higher voltage battery for more speed only if your ebike motor & controller are compatible. But higher voltage batteries are expensive & have charging costs.
Q3. Is a higher Ah battery better?
A higher Ah battery can improve your riding distance (range) on a single charge. However, it can increase your bike’s weight because higher Ah batteries are heavy as well as need more space. Also, they are expensive too. So it all depends upon your usage, if you are a long-distance rider, a higher Ah battery is better for you.
Q4. Can I buy an electric bike battery from an E-commerce store?
You can buy an ebike battery from anywhere as long as they sell the original & certified lithium batteries. Because the battery is a hazardous component of an ebike, it may catch fire due to internal damage or any other reason if they are not certified. So make sure you purchase it directly from the brand and stay away from DISCOUNTS!
Q5. How much does it cost to replace an ebike battery?
The battery is one of the most expensive parts of an electric bike. After every 3-5 years, it needs to be replaced with a new battery, its average price is somewhere between $500-$1000 depending upon many factors such as brand, quality, battery capacity (Ah), etc.