Common battery types for ebikes
Batteries for e-bikes can be broadly divided into two types, lithium and LiFePO4. The latter is also lithium but has a lower cell voltage and a very long life. Batteries for e-bikes can be broadly divided into two types, lithium and LiFePO4. The latter is also lithium but has a lower cell voltage and a very long life. The voltage of lithium cells varies considerably during discharge and the nominal voltage is therefore stated with 3.6V or 3.7V.
Chemistries
Commonly, e-bikes use lithium ion batteries which are available in different chemistries: LiCoO2, LiNiO2, Li-NiCoMn, LiFePO4 etc. LiFePO4 batteries have some advantages: longer cycle life and fast charge capability. The disadvantage is the lower energy density [Wh/kg], but note that the energy density of other lithium ion batteries degrade drastically after some years of usage.
A123 ANR26650
Note that I built this battery in 2014 so higher capacity batteries are available in the meantime. I prefer LiFePO4 battery cells ANR26650 from manufacturer A123. This battery offer high charge rates of 15 minutes, which allow fast charging on the go. There are more LiFePO4 manufacturers, but they differ in quality. Not just the LiFePO4 technology is the key to success, but its patented method in nanotechnology. LiFePO4, like any other multi cell lithium battery needs a BMS, which protects cells from over discharge and over charge. Also a balancer is required which usually combined with the protection circuit.
A123 LiFePO4 battery cell ANR26650
Here are some figures of the A123 LiFePO4 battery cell ANR26650:
- Battery cells old: 3.3V, 2.3Ah, 7.6Wh, 70g, specific energy: 108Wh/kg
- Battery cells new: 3.3V, 2.5Ah, 8.3Wh, 76g, specific energy: 108Wh/kg
- Recommended fast charge current 10A to 3.6V CCCV, 15 min
- Cycle life at 10C discharge 1000 cycles
- Self-discharge 2% / month
E-bike Battery Storage [EBC Insights]
LiFePO4 A123 battery 12s2p 4.6Ah 180Wh 43.2Vmax
Chinese LiFePO4 battery 36V / 10Ah
Note that I built this battery in 2014 so higher capacity batteries are available in the meantime.
LiFePO4 battery discharge graph
Panasonic CGR18650CG Li-NiCoMn battery 36V / 9Ah
Li-NiCoMn battery discharge graph
LiNiCoAl Lithium Nickel Cobalt Aluminum
This information is out of date, who can make an update? The highest specific energy of 265Wh/kg can be obtained with the new lithium ion battery chemistry LiNiCoAl from Panasonic and Samsung
Fast charge Lipo batteries
Standard Lipo batteries have a low maximum charge current of about 0.2C, but Lipo batteries for model aircraft allow higher charge and discharge currents. Some Lipo batteries have a maximum charge rate of 10C. ZIPPY Compact 5000mAh 10S 25C Lipo Pack Specific energy: 5A 37V / 1.161kg = 160Wh/kgMax. charge rate 5C.Note that Lipo batteries are not intrinsically safe, there is a risk of explosion or fire.
Lipo battery, charge rate 5C, specific energy 160Wh/kg
Terminology For Batteries
Voltage
Differential electric potential between two sites is what we mean by voltage. Each electron has its own unique energy level as it leaves the box.
When describing how quickly electrons travel, voltage is employed as a measure of speed.
The voltage of an e-bike battery usually ranges from 36 to 48 volts.
Capacity
The term “battery capacity” refers to the amount of charge that can be held in the battery. It is the greatest quantity of energy that can be retrieved from a battery given a particular set of circumstances, either in watt-hours (Wh) or in the more complex metric of kilowatt-hours or ampere-hours (Ah) (Ahr).
The total quantity of electrons we can get from a battery is the true measure of its capacity. When it comes to the range and torque of your electric bike, your battery’s Ah value is important.
The standard eBike battery capacity is between 8 and 15 Ah.
Energy
Watt-hours (Wh) are the units of measurement for the total amount of battery energy.
Unlike voltage, which describes how much energy each electron produces, Watt-hours describes the total amount of energy we get from all the electrons. Batteries are measured in Watt-hours, which is a quantity that represents the total amount of useable energy that can be extracted from the battery as a whole.
Simply multiplying the voltage [V] of the battery by the capacity [Ah] of the battery gives us the battery’s watt-hours of energy.
A total of 360 watt-hours of energy could be obtained from a 36-volt, 10-amp-hour battery. In order to get double the energy out of this battery (720 Wh), you may double either its capacity (36V 20Ah) or its voltage (72V 10Ah), or you may choose a middle ground between the two.
It’s time for a few concluding thoughts on eBike batteries. When this is reported in kilo-Watt-hours [kWh], which is simply the standard Wh output divided by 1,000 (720 Wh = 0.72 kWh), you will often see this written as a decimal number.
Certain individuals refer to a battery’s watt-hours as its “capacity”. This isn’t accurate in the strictest sense… A better term would be “energy storage capacity.” Amp-hours, as explained above, are often referred to as “capacity.”
Battery Cell
Batteries are composed of cells, which are the smallest units and are made up of four main components: cathode, anode, electrolyte, and separator. The performance of electric cars is heavily dependent on the battery cell’s properties.
Battery Packs
In order to provide the power needed by your eBike system, a pack of batteries is constructed from multiple smaller batteries that have been carefully packed.
Like your AA and AAA cells, there are two types of cells: cylindrical (such as the AA and AAA batteries) and prismatic (similar to the one in your phone). Among eBike battery packs, the most popular cell type is the 18650.
BMS – Battery monitoring system
Batteries made of lithium are lightweight and long-lasting, but you must use them within their limitations. If you want your battery pack to last a long time, you need a BMS (Battery Monitoring System). It acts as a buffer between the battery and the power lines, keeping tabs on all the cells’ voltages and, in most cases, the current flowing through them. The BMS should act if any restrictions are exceeded by securely shutting the power down. Ideally, the BMS will do nothing but shut you down if you ride until you utilize all the battery’s energy and avoid harm to the cells.
E-bike Battery Buying Guide: What To Look For?
Price
In terms of batteries, we’ve found that cost and quality go hand in hand. Ultimately, you’ll have to spend more money if you’re going to compromise on quality.
Product Details From The Manufacturer
Paying a premium for Panasonic, LG, and Samsung’s high-quality cells is a worthwhile investment in the battery market. To be safe, don’t buy an e-bike from a seller who doesn’t have or offer information on the cell maker.
Cell Chemistry
The best batteries for electric bicycles are lithium-ion (Li-ion). However, lead-acid batteries, which are three times heavier than their Li-ion counterparts, are substantially less expensive.
Li-ion offers a variety of cell chemistries to choose from. For electric motorcycles, the three most common batteries are NMC, LCO, and LI-FePO4 (Lithium Iron Phosphate) (LFP).
Size, weight and shape
When picking a pack, consider these three factors. If it doesn’t fit and is too heavy, you won’t be able to enjoy it on your bike. If you’re looking for a pack that has everything you need, you’ll probably be disappointed.
In order to avoid having to carry or place your battery on a bike rack or a flight of steps, many eBikers make the mistake of wanting a huge battery. This is OK until you need to attach it to your bike.
As we’ve discovered, finding the smallest and lightest battery pack that does the job is the key to a perfect configuration. Having a pack with twice as much energy as you require may seem like a Smart idea, but this may prove detrimental on even the longest of trips.
Battery Position
The battery pack of an eBike might be difficult to install. As a result of the many options, some packs were placed in between the wheels, which provides the greatest possible distribution of weight and rider comfort, while others were placed on a rear rack or saddlebags, which is handy but may have a detrimental impact on handling. Shape and weight are key factors here!
The finest eBike batteries, in our opinion, will be produced using Panasonic, LG, or Samsung cells using LFP or NMC chemistry.
Types of eBike Batteries
Here are some options to consider:
LEAD (GEL) BATTERIES
It takes approximately eight to ten hours for a dead battery to fully charge, which has decreased over time as people have become more aware of the dangers of lead batteries.
Additionally, lead batteries have lower capacity and manufacturing costs because of the quality of the compounds used.
LITHIUM-ION BATTERY (LI-ION)
Lithium-ion batteries, which are now the most common on the market, will be found in newer or more recent electric motorcycles.
As a result, lithium-ion batteries have the lightest and most energy-dense batteries on the market, and as a result, they have the greatest possible range and lifespan.
LIFEPO4
It is possible to use lithium iron phosphate (LiFePO4) in a broad variety of applications and in any climate because of its wide temperature operating range. There are several advantages to using this type of battery: extended life, charge efficiency, and no maintenance, as well as the fact that it can be charged rapidly.
Despite the fact that they are fairly new to the market, they are excellent long-term investments because of their lengthy lifespan.
Range of eBike Batteries
A battery pack’s range is determined by the quantity of energy it contains and is expressed in Watt-Hours (Wh)
The battery capacity in Amp-hours is multiplied by the battery voltage in Volts to arrive at the watt-hours.
Let’s say that, on average, it takes 30Wh of energy to go one mile.
12 miles per charge is what you can expect with a 10Ah, 36V battery.
For example, 10Ah x 36V = 360Wh, which equals 12 miles of driving.
To get a more accurate idea, subtract 15% from the manufacturer’s recommended range and use this inflated value as your true range.
Is It Possible to Overcharge an E-Bike Battery?
Now that we know a bit more about electric bike batteries, let’s answer the question: can you overcharge an electric bike battery?
The short answer is yes, it is possible to overcharge an electric bike battery. However, it is not often something that will happen if you accidentally leave your battery plugged in for too long.
Instead, overcharging most often occurs when there is a problem with the battery charger.
How Do You Overcharge an E-bike Battery?
Rechargeable batteries are designed to cycle off and on as they charge and discharge, which helps to protect the battery from overcharging.
When a battery overcharges, it receives too much voltage for too long, which can damage the battery.
There are several ways an electric bike battery can overcharge. These include:
- Using a charger not designed for the battery
- Using a charger with the wrong voltage
- Leaving the battery plugged in for too long (less common due to the battery’s built-in protective measures)
- Charging the battery in extreme temperatures
Can Overcharging Damage an E-bike Battery?
Regular overcharging of batteries can cause several problems.
Reduced Battery Capacity
Overcharging can reduce the capacity of your battery, meaning it will no longer be able to hold as much charge.
Why does this happen? When a battery overcharges, chemical reactions may occur inside it, breaking down some of the materials and reducing its capacity.
Increased Battery Temperature
Overcharging can also cause the battery to heat up. When a battery is overcharged, it produces more heat than it can dissipate, which causes the temperature to rise rapidly.
Although rare, fires have resulted from overheated e-bike batteries. As you can imagine, the damage can spread to more than just your battery. It may also damage the bike itself.
Sulfation
Sulfation is a process that occurs when lead-acid batteries overcharge, resulting in a build-up of lead sulfate on the plates inside the battery. In turn, the battery capacity reduces.
Decreased Battery Life
How is battery lifespan defined? Battery lifespan is the number of charge/discharge cycles a battery has. Overcharging a battery can shorten its lifespan by reducing the number of cycles it can go through.
A complete charge cycle occurs when a battery is charged from empty to full and discharges back to empty. When a battery overcharges, it goes through partial charge cycles, which can shorten its lifespan.
Caring for an Electric Bike Battery
It is imperative that you take care of your electric bike battery if you want it to last. There are a few simple things you can do to extend the life of your battery and keep it in good condition.
Storage
How you store your battery has an impact on its lifespan. You should always keep your battery in a cool, dry place.
Avoid storing it in direct sunlight or near any heat source. Heat can cause chemical reactions inside of your battery and damage it.
You should also avoid storing your battery in a completely discharged state. Make a habit of it, and the battery capacity will reduce.
If you need to store your battery for a long time, it is best to keep it at around 50% charge.
It is good to recharge the battery every few months to keep it in good condition.
Charging
It is essential to use the correct charger for your battery. Using a charger not designed for your battery can damage it. Make sure you always use the charger that came with your bike or one specifically designed for your battery.
It is also important to avoid overcharging your battery. As we have seen, this can damage the battery and reduce its lifespan.
Always follow the instructions that came with your charger and stop charging when the indicator light turns green.
When charging the battery, ensure it is done in a cool, dry place away from flammable materials. You should also avoid charging the battery in extreme temperatures as this can result in permanent damages.
Ebike battery storage voltage
It’s no secret that here at Liv we’re huge fans of electric bikes. Just the mere mention of our women’s E-bike range breaks us out in a big smile.
But. we’ll also put on our serious face and discuss electric bike battery safety with you. Because we know that E-bikes, with their high-tech batteries, can sometimes feel complex.
That’s why we’ve broken it down in this article. So read on to discover :
- What’s inside an electric bike battery (the techy stuff)
- How we ensure the highest battery safety standards on our Liv E-bikes
- The 13 must-know best practices for ultimate E-bike battery safety
The techy stuff: What’s inside an E-bike battery?
E-bike battery packs consist of individual battery cells containing lithium-ions. These battery cells store the energy to power the motor.
E-bike batteries are made with either cylindrical, prismatic, or pouch-shaped cells. The shape of these cells is really important. High-quality E-bike battery suppliers like Panasonic, Shimano, and Bosch use cylindrical cells because they handle higher temperatures without deforming.
Aside from the individual battery cells, a critical component inside an E-bike battery is the battery management system (BMS).
The BMS is hugely important as it regulates the individual performance of each battery cell. Regulation is important because even when they’re installed at the same time all the individual batteries don’t drain, deteriorate or perform at the same rate. Some cells last longer than others, some cells will drain slower than others and some will glitch out and cause more problems than others.
Left to their own devices, with so many cells acting independently, you’d encounter performance and safety issues with your E-bike.
So the BMS helps to provide your E-bike battery with long-term consistent performance.
We like to think of the BMS as the competent ride leader overseeing a group of different riding abilities and working to keep everyone together on the trails.
How we ensure the highest battery safety standards in our Liv E-bikes
At Liv, we take your safety VERY seriously. That’s why our E-bike batteries have been co-developed in partnership with the biggest and best battery manufacturer available – Panasonic.
Although other brands may purchase Panasonic batteries Liv has gone the extra mile. or two.
Firstly, we work closely with Panasonic to co-develop our batteries. The output is an e-bike battery that’s completely proprietary to us and designed to the highest safety standards.
Secondly, not only does Panasonic manufacture the cells and the battery management system on our E-bikes but they also assemble and test them for us.
So by investing in a Liv E-bike you can feel totally confident you’re getting a safe, reliable, and high-performing battery that’s developed, assembled, and tested by industry leaders. You won’t find our e-bike battery on any other e-bike on the market.
Liv’s EnergyPak E-bike battery is also distinct from other brands because it has individual separators (rooms) inside. This helps prevent heat from spreading from one cell to another.
Our BMS – aka the capable ride leader – monitors the battery pack and individual cells to make sure each cell is regulated for maximum efficiency and to prevent overheating.
While your Liv E-bike is charging, Liv’s Smart Charger continuously communicates with the battery to ensure individual cells are charged at the optimum rate. Also, in extremely hot or cold weather conditions the Smart Charger will adjust the charging voltage for optimal battery efficiency.
simple do’s and don’ts for ultimate E-bike battery safety
E-bike battery safety: The Do’s
- Do purchase your E-bike from a reputable e-bike brand.
- Do always use the battery and charger that originally came with your E-bike.
- Do go to an authorized dealer if your battery is damaged so they can check it before your next ride.
- Do remove your battery when transporting your e-bike to protect it from damage.
- Do store the battery at room temperature in a moisture-free environment to avoid unnecessary damage to the cells.
- Do keep the battery away from children and pets.
- Do stop the charging procedure immediately if you feel concerned.
E-bike battery safety: The Don’ts
- Don’t modify your E-bike or let your ‘helpful’ friend tinker with it either. For maintenance, always go to an authorized dealer for your E-bike brand.
- Don’t charge your E-bike around flammable materials.
- Don’t store your E-bike battery in a damp place.
- Don’t subject the battery or charger to high-impact eg. by dropping them
- Don’t cover the battery or charger or place objects on top of it.
- Don’t leave your battery at full charge if you’re storing it for a month or more. It is also best to remove the battery from the bike and store it at 60% of its capacity. You can make use of Liv’s Smart Charger which has a useful 60% charge function to ensure safe storage.
Measures in Case of an Emergency
Observing the tips in previous sections decreases the chance of an emergency for any e-bike owner, but unfortunately, incidents happen. So, familiarize yourself with the measures to keep yourself, your dear ones, or anybody around safe.
Generally, you can think of 3 steps when a fire starts on your Li-ion battery:
Depending on the size and type of battery, there are various ways to put off a Li-ion battery fire. You need to be quick to react and prevent fire from spreading.
Since fires caused by Lithium-ion batteries are Class B fires. you should opt for a standard ABC or dry chemical fire extinguisher. Class B classification is to distinguish the flammable liquids. Because Lithium-ion batteries contain liquid electrolytes, they fall into this category.
When burning, the poisonous liquid acts as a conductive pathway for fire and helps it spread faster.
You can use the extinguisher to spray the fire until it is put out. The stages are as follows:
- Pull out the safety pin to use the extinguisher.
- Target the nozzle at the base of the fire.
- Squeeze the handle firmly
- To ensure that you put out the fire wholly and correctly, sweep the nozzle back and forth across its base.
If you suspect something is wrong (e.g., the Battery case getting warm, liquid leaking, or the battery making noises), you should put it outside in a safe, open space and wait for the battery to go back to normal. Please note, do not try to handle the battery that has caught fire or leaking fluids as it can be hazardous to you.
If the battery catches fire, wait for all the cells to burn while trying to extinguish it.
Li-ion battery fires are thermal runaway events type. Subsequently, e-bike battery fires can pose several hazards, like poisonous smoke, flames, and metal projectiles. After taking the necessary measures explained above, you should call the nearest fire station in your area if you cannot contain the fire.
Judge the severity of the situation and do not approach the burning battery. Wait until firefighters arrive if you are not comfortable dealing with the fire.
What Safety Features Do ENVO Lithium Battery for Ebikes Contain?
To ensure our products live up to your highest quality and safety expectations, ENVO has sought and awarded the first UL 2849 ebike certificate in Canada.
Recent progress in BMS (Battery Management Systems) has led to better control of the battery pack in e-bikes from several perspectives, like the battery working and its charging and discharging. The final goal of ENVO is to optimize the performance and longevity of its batteries.
Though we ensure to provide e-bike batteries that exceed industry standards Following are some of the safety features of ENVO Batteries.
ENVO Batteries cut off charging if the charging voltage or current gets higher than the definite range; this ensures that charging is discontinued in case of any fault.
Cell balancing improves the available capacity of the battery; additionally, unbalanced cells can be damaged and cause failure in the long run.
This is why ENVO Batteries come with cell balancing and cell balancing cutoff. This way, the battery is shut down if one of the cells is permanently damaged and cannot be balanced.
During the operation of the product, the voltage and current value are measured; if the voltage gets too low or the current value gets too high, the BMS cuts off the battery for safety reasons.
E-Bike Battery Fires: 5 Safety Tips To Avoid Them
Short-circuit in Li-ion batteries are always dangerous. It may damage your battery and decrease its lifecycle at best. And at worst, a short circuit can lead to severe risks like a lithium battery fire or burst, causing injury, property damage, or even death.
ENVO Batteries include short circuit protection designed to monitor the battery’s voltage to prevent hazardous situations arising from short circuits in the batteries.
Envo Li-Ion batteries include a temperature cutoff protection mechanism that shuts down the battery when the temperature value exceeds the safe limit.
Conclusion
Li-ion batteries are widely used in e-bikes today. Though these batteries are not inherently dangerous, some ebike users’ inappropriate treatment has led to many fire incidents. This article discussed the safety measures you should take when charging your lithium-ion battery.
We also discussed the proper use and storage methods you can observe when dealing with such batteries.
Finally, we discussed the safety measures undertaken by ENVO to ensure a high-quality battery is used in our e-bikes. Such measures included short-circuit protection, cell balancing, discharge protection, and temperature cutoff protection.