Introduction: Customized Lithium Battery Packs for E-Bike
About: Being a science student i love to indulge in projects related to engineering as i love to learn things practically. About DIY KING 00 »
We recently converted our bicycle into an e-bike using brushless outrunner motor from hoverboard, and that thing have crazy amount of power. But that crazy power drains the hobby grade lithium pollymer batteries like crazy fast. As we have been previously using two 5.2 Ah 11.1v battery packs that offered a total capacity of nearly 110 watts hour. With this capacity we can barely go beyond 4km of range with heavy foot over throttle.
Now we can get more fortunate as during this whole situation we came across an old lithium ion battery pack during our visit to scrap yard and we suspected the battery to be still alive.
Now this instructable is your guide to design and built a customized lithium ion battery pack for your electric bike totally out of scratch and scrap.
Hang in there as we are going to built 600 watts hour battery pack thats going to give us a 20-25 km range on our electric bike and all that within 20 USD. So time to get hands dirty.
Supplies
As always you dont require a particular set of tools for this project but having following can get the job done as discribed:
- Soldering iron
- Sucker gun
- Soldering wire
- Knife cutter
- Multimeter
- A DC watt meter
- A nichrome heating filament to act as a load
- A 3d printer
The material required for this project are:
- source of lithium ion cells, to name a few it could be an old electric bike or a laptop.
- Printing filament
- Epoxy
- XT-60 connectors
- A BMS (Battery Managment System)
If i miss anything here put it down in the Комментарии и мнения владельцев below.
Step 1: Sourcing Used Lithium Ion Cells
Without any doubts, lithium ion batteries offers great specifications and the benifits such as the weight/volume saving, crazy discharge rate are a few to name here. But all that come at a hefty price specially if you are aiming to get a battery pack for you electric vehicle as you are aiming for above 100 wattshour (Wh) obviously and there the price starts to add up alot.
So, one way is built your own lithium ion battery pack using cells from old battery packs from sources such as a damaged electric bike or a laptop(although they dont offer high discharge cells) while totally customizing the battery pack to fit perfectly within your vehicle.
For this project we found an old battery pack from a rejected lot of electric scooters from an old scrap yard. Now lithium battery packs from used sources can be a good deal with a considerable amount of capacity still left in them if you are going to consider the following things:
- In case of soft pouch lithium ion battery as this one, the physical condition matters alot. The battery must be in good shape with no major dents and definately no puntuchered. Besides, if the battery pack is swelled it means that the cells are puffed up due to over charge or over discharge. So be carefull not to pick up a pack thats balloned but you can go for the one that offers multiple cells and a few of which are swelled as you might end up getting the rest of them working perfectly fine.
- Generally lithium ion cells are in good working condition if they are holding a potential above 3v as the onces below that level are usually puffed up and are supposed to be inside the bin(Should be recycled properly) and definately not over the workbench.
- Check the overall voltage of the battery pack if the individual cell voltage can’t be measured. Divide the total voltage to the number of cells that battery has in series connection. If there is anything above 3v, you probably won’t regret getting that one.
- Gererally lithium ion batteries are equipped with a BMS(Battery Managment System) that maintains the individual cell voltages and offers a bunch of safety features. When not used for long it might drian the battery pack slowly and when the battery drops below a certain level, the BMS cuttoff the supply and thus you might end up getting 0v over the output, to troubleshoot connect the battery to the charge source for a couple of minutes and check if it hold a potential above the mimimum limit.
So with all those precautions we get ourself the battery pack, it was scratched but not dented. The battery pack was a 10 cells 36v 21Ah that sums upto 756 wh stated battery capacity. We weren’t able to measure the individual cell voltages but the good thing is that the overall unit is standing at 38v which means that idelay each cell has to be at 3.8v thats a real good sign for a healthy battery. The battery pack seems to be puffed from one side but will see that later on.
Step 2: Tearing the Battery Pack
To start with we have to get our hands on healthy cells and for that we started tearing the battery pack. Now as I mentioned earlier these are soft pouch pack unlike 18650 cells that offers hard casing, so becarefull with the knife cutter as it can easily punther the cells and a fully charge cell can easily explode with that.
Once we teared off the battery cover we found the packs to be arranged in two rows. Each row has five packs with each pack having four individual lithium ion cells connected in parallel while the pouches are connected in series. The front is equipped with a BMS.
Step 3: Monetring the Individual Cell Voltages
The next thing is to measure the individual cell voltages. To our surprise nine of them were standing at 4.20v, thats kind of an ideal condition as it the maximum voltage limit for a lithium ion cell. But as we remember the whole pack was holding a potential at around 38v which means that one of the corner cells is at 0v and thats the case. As discussed in the previous step the whole pack puffed up due to over discharge and i guess thats the reason why they throwed the battery pack.
Everything is good but there is something wrong, probably the BMS as it would have drained that pack but with one cell standing at 0v the BMS should have cutoff the battery pack but thats not the case as we measured 38v at the output, but will figure out that later.
Step 4: Capacity Testing
The individual cells voltages can be a sign for a good lithium ion battery but its just a good initial guess for healthy battery pack and there is no gurantee that its holding a good capacity.
So to test the actual battery capacity we have removed the puffed cell, jump connected the rest of them so that we have total nine packs connected in series and with a nichrome heating filament connected across a DC watts meter we are ready to test the battery capacity.
The heating filament offered nearly 500 watts of dummy electrical load. It took just over na hour to drain the battery pack during which we continiously monitored the battery pack voltages and the seems to remain balanced throughout the drain. We did a manual cutoff at 27v as 3v is a safe limit for each cell to cutoff for lithium ion batteries.
The battery pack delivered arround 540 Wh (watt hour) thats arround 80% of the original stated battery capacity. So we are good to design the battery elcosure.
Step 5: Designing the Battery Enclosure and Holder
One of the main challange for converting the bicycle is to pack it with punch of power to make it fun to ride. The Brushless outrunner motor that fulfilled our power needs now require a good deal of battery capacity and we have very small space to get a sufficient amount of battery capacity.
Now customizing the whole battery pack helped us to design two battery packs. We later replaced the puffed pack with a working one from another battery, so we had 40 individual lithium ion cells to work with. Thus we decided to built two seperate battery packs, each one of which is a 10 cell pack with each pack having two cells in parallel and thus forming a 36v 300 Wh battery pack.
The design of the enclosure was simple, ten compartments to separate the packs with a bit of head room for BMS and holders for a pair of XT-60 male and female connectors for discharging and charging the battery pack.
Both the battery packs are designed to fit below the bicycle seat and for that we have designed the battery packs holder. The holder is designed to slide over the seat holder and tightened with three allen key screws with nuts on the other side. Once the battery packs are slide in place the top holder helps to keep the battery packs in place.
Step 6: Dissassembling the Battery Pack
Later we dissassembled the battery pack and we started by desottering the connection over the PCBs, yup Printed Circuit Boards and here I would love to take a moment and thank Stariver Group for making this project possible. With over 20 years of experience for manufacturing and assembly of customized printed circuit boards they are providing some of the finest services out there at an out standing price right at your door step. So take a moment and head up to their website to order your customized PCB for your upcoming project.
Now once we removed the PCBs, we than carefully took cells apart using some alchol dipped cloth and a ruller. Be carefull during this step as you can easily puntcure the cells if you are not carefull.
Step 7: Assembling the Cells
The individual cell voltage is measured and then we mentioned the polarity of each pack before throwing them inside the enclosure. In total there are ten packs each one of which has two cells connected in parallel while all the ten packs are connected in series. For that we have to place the packs alternatingly inside the enclosure.
Once all the packs are in place we sottered the tabs carefully as there are a whole lot of exposed terminals ready to bite anything that shorts them, so again be carefull.
Next we placed the male and female XT-60 connectors within their holders and sottered the positive terminal directly while the negative terminal will be connected through the BMS.
Step 8: The Battery Managment System
Have you guys noticed how many times I have discussed the voltage of individual cells, yup alot and its because of the face that lithium ion cells are very sensitive with the voltage. The maximum charge potential is 4.2v, the minimum cutoff voltage limit is 3v while the nominal voltage is 3.6v.
Now with this much cells arround we need an intermediate unit that manages the individual cell voltages that occur due to various charge and discharge cycles with sligh variation within the resistance of each cell. For that we are going to use a BMS (Battery Managment System) and for our battery pack we needed a 10 cells BMS as they are ratted for the number of lithium ion cells that are connected in series and also the maximum discharge current that you are planing to drain. As the original battery pack was a 10 cell too so we have used the same BMS.
First we connected the individual cells to the BMS and then we have connected the charge negative, discharge negative and battery negative terminals. Next we mounted the BMS to the top cover using a couple of screws.
Step 9: Retesting the Battery Pack
Before we glue the enclosure we ran a complete charge cycle followed by a discharge using the same nichrome heater and wattmeter setup as previously. During the whole test we took a close eye over the battery voltage and individual cell voltages. The battery provided the same capacity except that the BMS failed to cutoff the battery power as it went below the minimum cutoff voltage. Luckily we were monitoring the unit so we did a manual cutoff and later replaced the BMS to the one from the hoverboard battery pack and that worked absolutely fine.
Step 10: Gluing the Enclosure and Finishing Touches
Once the BMS was replaced we glued the top cover using epoxy to make the enclosure water proof. Next we printed and glued the face plate mentioning the specifications of the battery pack.
Step 11: End Results
The outcome of the project is just way too good. Those little buddy boxes have 600 watt hour of power to offer and thats just insane as this whole thing is built out of an old battery from scrap. We have tested the battery packs with our electric bike thats still under finishing work but the results were promising. We are upgrading the bike to achieve 60 to 70km/h of top speed and with that conversion the bicycle pulls arround 30 Wh with the maxmimum pull over the throttle which means that now with these two battery packs we can easily get upto 20 to 20km of range on a single charge depending upon the throttle we pull off during the ride. Isnt thats too good for an electric bicycle conversion.
The whole project was a good learing curve and cost us 20 USD including eveyrything and in the end we have an awesome pair of battery packs the fits right under the bums 😛
Our electric bike conversion with this battery pack, a crazy motor hack and with a 3000 watts BLDC Motor controller will be coming this weekend on our YouTube channel so do vist, subscribe and break that bell icon to get notified the moment we publish the built video.
Will be there with another awesome project video.
Electric bike batteries: everything you need to know
If you’re reading Cycling Weekly, you probably know something about bikes – which means you also know plenty about electric bikes. But one big difference is the battery used to power the best electric bikes.
If the battery is not charged, you can still pedal and roll on an electric bike, but you will lose its real utility and ultimately its fun, and you will be left with a heavy machine to carry on with.
What are eBike batteries made of?
Electric bikes in the UK tend to come with either Lithium Ion (Li-Ion) or Lithium Polymer (LiPo) batteries. In China, on the other hand, lead acid batteries are still the most common ones used. In 2014 – according to the China Bicycle Association / IdTechEx – 35 million eBikes were sold on the Chinese market, and just 2.8 million of them had lithium battery.
Because of problems with quality and weight, lead acid batteries are not common in the rest of the world. In Europe, for example, acid lead batteries represent less then one per cent of the total; while 96.5 per cent is taken by Li-Ion and two per cent by LiPo (source: Greenfinder market report).
Specifically, battery packs are made up from many cells: the lead acid ones are similar to those we use on our cars, while the lithium ones use the same technology as mobile phones. Apart from the chemical component inside their cells, the main feature that differentiates lead acid and lithium batteries is their size: the lead ones are heavy and have a short life (200 to 300 charge cycles), while the lithium ones are smaller and can last longer (from 500 to 1,000 charge cycles).
The LiPo batteries are a further development of the Li-Ion ones – they are relatively cheap and small in size, but their service charge is unclear and they are quite fragile.
How long will my battery last?
That’s a tough one to answer. It depends on the power of the battery (typically 24, 36 or 48V), the power of the bike (limited in the UK to 250W), the bike’s battery management system, and the way you ride. Some bikes allow you to choose different levels of assist to prioritise speed or battery life, which makes predictions of battery life even more difficult.
Typically you can expect somewhere between 25 and 70 miles of travel on a single charge of an ebike. If you’re riding hard on full power expect less; manage your battery life well and you could get more.
Many retailers suggest charging the battery at least once a month if the bike is not ridden much, and say that the more the bike is ridden, the stronger the battery will be. All batteries, though, will deteriorate in time and they will need to be replaced and disposed. When that time comes, it’s best to ask your local retailer how to dispose of the battery, but bear in mind that local authorities should provide recycling and disposal facilities.
Watch: What’s it like to ride an ebike?
Where are the batteries placed on an ebike?
The battery’s placement on the bike depends on different factors, especially the shape of the bike’s frame. Most electric city bikes (more than a half) will have the battery mounted on the carrier rack, while mountain bikes usually have them on the down tube.
How much do electric bike batteries cost?
The batteries are the heaviest and the most expensive part of an electric bike. A lithium battery (36V and 10Ah) could cost around £200, but the do vary.
Technology is advancing fast, so check with your ebike retailer first to ensure that battery isn’t outdated or difficult to replace.
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Nick Busca is a freelance cycling and triathlon journalist. He is also a certified triathlon coach and personal trainer.
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How Long Does a Battery Last on An Electric Bike?
Batteries on new electric bikes can last anywhere from two to five years. The lifespan of an e-bike’s battery is determined by three main factors:
- the type and brand of battery being used
- how many times the battery has been charged during its lifetime
- the battery’s age
A single e-bike battery can be charged thousands of times before a rider needs to replace it, with each charge taking riders ~100 to 120 km on a standard electric bike.
Here’s a quick look at the different types of electric bike batteries, as well as some suggestions for extending your battery’s life.
You’re not the only one who isn’t sure how long electric bike batteries last.
Why charge cycles are important for e-bikes
The battery life of an electric bike’s battery depends on the number of times its been charged (with each charge known as a “charge cycle”). When the battery is drained from 100% to 0%, that counts as one charge cycle.
Going through these cycles slowly deteriorates the battery, and shortens how long it lasts before needing to be charged again.
Should you charge your electric bike battery often?
You should generally charge your electric bike’s battery when whenever it reaches the 30-60% charge range.
Some people mistakenly think that not using your battery much can make it last longer. In reality, not using your battery does more harm than good.
The battery of your electric bike and other battery-powered devices tend to discharge even when they’re not being used. This phenomenon is commonly referred to as self-discharging. Excessive self-discharging can also render irreparable damage to your e-bike’s battery, so you want to make sure you actively use it.
It’s important to charge your electric bike battery carefully to extend its life.
Types of electric bike batteries
The lifespan and performance of an electric bike battery also depend on the type of battery being used. There are three broad classes of batteries used for electric bicycles:
Lithium-ion batteries
Lithium-ion batteries are the most widely used battery for electric bikes. They can survive upwards of 1000 charge cycles in a lifespan. over, the new Lithium Phosphate battery has proven to be more durable and safer to use than other types of batteries.
Nickel batteries
Nickel batteries have similar power to lithium-ion batteries but tend to self-discharge at a faster rate. They can withstand about 500 charge cycles before dipping in performance.
Lead batteries
Lead batteries are the oldest type of battery used for e-bikes. If you buy a new e-bike, its battery will almost certainly not be a lead one. Lead batteries have a charge-cycle threshold of just 300 charges and are heavier than their lithium-ion counterpart.
Also note that your electric bike’s battery life is tied to the quality of its materials and the company that manufactured it. Many times, even a lead battery from a good and reputed manufacturer lasts longer than a substandard lithium battery.
Which battery should I choose for my electric bike?
The empire supports lithium-ion batteries, but which type should you pick?
Regardless of the battery type you choose for your electric bike, make sure it has a two-year manufacturer warranty. Sometimes batteries have been caught discharging much quicker than expected, so it’s best to be safe in the event your battery is defective.
Lithium-ion batteries are the standard for most e-bikes today, but they can end up costing more than nickel and lead batteries. They also must be well maintained — being more sensitive to high and low temperatures than other types of batteries.
When should I replace my electric bike’s battery?
If you’ve had your battery for two years or longer and start noticing a decrease in performance, your battery’s life is slowly coming to its end. A lack of power and even fluctuation in voltages are both signs pointing toward the need to change your e-bike’s battery.
Another sign that your battery is on its last legs is that it needs to be recharged more frequently. If you find yourself recharging your battery more often than in the past, it’s begun to decay and should be replaced.
How to extend your electric bike’s battery life
Your battery’s durability, like any other electrical device, is directly tied to the amount of care you give it. External factors like temperature and humidity can impact your battery’s life, for instance, so you need to make sure you don’t leave your e-bike outside for long periods of time (especially if you live somewhere like Phoenix, Arizona).
Here are a few tips for improving your electric bike’s battery life:
- Use the charger that came with your battery, because it’s optimized specifically for charging it.
- If your battery seems like its overheating, don’t start charging it. Instead, allow it to cool down first.
- Don’t run your battery down to 0% charge. Instead, recharge it when it’s been used about halfway.
- If you plan on going a long period of time without using your e-bike, make sure to take the battery out. Also turn the battery on once in a while to avoid excessive self-discharge.
- Avoid overcharging your e-bike’s battery by unplugging it at 100%. If you charge your battery overnight, make sure you unplug it first thing when you wake up.
- Store the battery in a cool and dry place. This can be done by parking your e-bike somewhere shaded or out of direct sunlight.
- When cleaning your electric bike’s battery, use a dry towel — nothing wet. Water can lead to further corrosion of the battery, so don’t unintentionally shorten its life while maintaining it.
Ebike Battery Explained – Guide Charging Tips
Are you wondering why your ebike didn’t last the city ride? Well, your battery could be the cause.
As small as it may be, an e-bike’s battery is its lifeline.
Having the right cell for your two-wheeled electric bike goes a long way in saving you money and time.
In this ebike battery guide, we discuss everything you need to know about the best ebike battery for your electric bikes including types of cells, cost and some charging tips.
Classes of Electric Bike Batteries
There are four main types of e-bike batteries. These include:
Nickel cadmium batteries (NiCd)
Nickel metal hydride batteries (NiMh)
NiCd batteries are the least popular options to consider for your e-bike. That’s because they are expensive and is a technology of the past. Both nickel and cadmium are nasty pollutants, thus being hard to recycle.
NiMH batteries are more efficient than NiCd batteries; however, they are still expensive. The success of lithium batteries is increasing the rarity of these batteries. The advantage of NiMh batteries is that they are easy to recycle and last longer.
SLA batteries are the cheapest and easiest to dispose of or replace. However, they need proper handling as they can following a deep discharge. The SLA batteries don’t last longer than the competition, thus making them unreliable. Their unreliability can pose serious problems to your transportation needs.
Lithium batteries are the best because they are affordable, light, and provide more power. Almost 90% of e-bikes use lithium batteries because most manufacturers have dealt with all the past security problems of catching fire and self-destruction. Some variants of lithium batteries include:
Lithium Manganese batteries (LiMg204)
Lithium Cobalt batteries (LCO)
Lithium-ion batteries (Li-pol)
How long will my electric bike battery last?
These batteries can last between three to five years. However, it will depend on whether you have protected the batteries from temperature fluctuations and kept them in a dry place.
Again, the number of times you charge your e-bike cell from 0 to 100 percent has an impact on its lifespan. Regular full charging reduces the half-life of your battery.
The battery longevity can also depend on the energy management system on the bike and your riding habits. Some e-bikes have energy management systems that you can turn on depending on your preferred riding mode. You can use the EMS system by activating the pedal-assist mode, thus easily regulating the levels of charge used.
What is the ideal capacity of an e-bike battery?
The capacity of a battery is the charge or power that it can maintain. The capacity provides you with added range on your e-bike. Selecting a battery that has a good capacity means that you won’t spend time recharging it frequently.
Your e-bike battery capacity is indicated in either amps hours or watt-hours. You will come across batteries that range from 250W to 750W. These batteries deliver power differently, thus ensuring that your e-bike lasts longer.
Before purchasing the battery, check on the different capacities and power delivery options. For example, you can find a 500WH battery that can deliver 500W of power in an hour. Such a battery also has the potential of delivering 250W in two hours and 1,000Win 30 minutes.
Electric Bike Battery Power Capability
Power capability refers to the amount of energy the battery can deliver for use within a specific period. For instance, your e-bike battery may have a capacity of 1,000 watts of power. However, it may deliver only 5W to the motor at any given time.
The power produced by the motor is known as torque, and this will vary from e-bike to e-bike.
You should choose a battery that can deliver up to 1,000W to ensure that you always have all the power you need. A normal pedaling speed of 9mph requires 30W. If you want to get to 20mph, you require 220W. Having a battery that’s capable of 1,000W means that you have more power at your fingertips.
How much does an e-bike battery cost on average?
On average, you can spend between 500 to 900 on a good e-bike battery. The price will vary depending on the battery type, wattage, and brand. To ensure that you get value for your money, consider assessing the cost per WH of each battery.
If you want a cheap battery, you should also expect to obtain cheap quality. Be careful when purchasing these batteries because, in most cases, you get what you pay for. That is, you can purchase a battery that might wind up being a potential fire hazard.
E-bike Battery Prices
Some of the best batteries are from Yamaha, Shimano, and Bosch. These companies provide you with reliable batteries that range from 400WH to 650WH. Comparing the of each battery option allows you to know which one has the best value for the money.
Besides, you can assess your budget to know the battery that can work best. From these companies, you will find the cheapest offering of 565 from Shimano. It’s a 418WH battery that’s capable of 38mph. That’s enough speed if you are planning on using the bike around the city.
Despite your budget limits, you can find a battery for your bike.
E-bike Battery Care. Lithium-ion cell
To ensure that you get the most out of the battery, you should begin your care from the charger. Get the right charger that can either deliver 36v or 48v, depending on the battery system. You should also consider plugging in the battery and let it charge till full for the first time.
After the battery fully charges, you should test it out. Conducting a test ensures that there isn’t any voltage sag.
How to Test E-bike Battery
The first way of testing an e-bike battery is through a multimeter. It provides you with precise measurements since you connect it directly to the battery. You should, however, be careful to avoid short-circuiting the battery and damaging the charging ports.
Before you commence the test, you should fully charge the battery and remove it from the bike frame. On your multimeter, you should choose the “test load battery” option. After which, you can proceed to assess the voltage and then the current of the battery.
E-bike Battery Output Voltages Options
The voltage of your e-bike battery is the equivalent of horsepower from a car’s engine. Most electric bike batteries will range from 24V, 36V, 48V, and 72V. The higher the voltage, the greater the power of your bike cell.
The most common voltage option is 38V; however, there are other e-bikes with either 24V or 48V. Most e-bike manufacturers will spec their e-bikes depending on the power to cost ratio. If you want a 72V bike, it might have to be custom and expensive.
How to Charge an Electric Bike Battery. Charing Tips
Charging your battery ensures that it can lead a long, healthy life. You should plug in the charger for a new battery or bike and leave it for at least 12 hours. The initial charge ensures that there is power flowing through all the battery cells and helps condition the battery.
If you use your e-bike regularly, you should charge the battery regularly. Never allow the bike or the battery to discharge completely. The best option is therefore to recharge the battery whenever it is nearly half-full.
Following safe battery charging principles ensures your bike delivers when you need it most.
How do I Select the Best Battery for My E-bike?
Picking the best battery requires you to consider the available types. The best solution is the lithium battery since it’s a compact package that packs more capacity than its competition. It’s also an affordable and durable solution for your e-bike.
Besides picking the type, you have to know the budget you have to spend on the battery. Some batteries range from 500 to 900. Consider assessing your budget to know which lithium battery will be worth your money.
The voltage options of the battery are also crucial. If you want a battery that can transport you around a city or town, a 36V option will be enough. However, you can opt for a 24V if you don’t care much about the power, a 48V for a bit more power, or a custom 72V for the best performance.
Are e-bike batteries interchangeable?
Yes, some e-bike manufacturers offer interchangeable battery options for their bike lineup. However, this option isn’t available for all the other e-bike brands. All you can do is replace a battery with an option that can work with your e-bike.
E-bike Battery Sizes
Most e-bike batteries vary from 250WH to 1,125WH. Your choice depends on several factors like how far you would like to travel on a single charge, whether you want power settings, if the e-bike is a long-term investment, and the technology available.
E-bike Battery Connector Types
A good battery connector can impact your e-bike experience. Picking the right connector can be arduous, especially if you don’t know what you are dealing with. Since there are lots of options in the market, let’s look at a few:
While most connectors have separate male and female plugs, the Anderson Powerpole connector stands out with its genderless design. Having one pin and a single housing unit, the connector gives you the versatility of using it either as the load or in the source. Also, if you want to establish a multi pin connector series, Anderson Powerpole is a great consideration as it allows stacking. Thanks to its dovetail joints.
Deans plugs are among the smallest connectors an e-bike owner can purchase. Just like their size, they are quite cheap. So if you are on a tight budget but looking for a connector that can handle large currents, consider Deans plug. Noteworthy, they have poor moisture resistance and are quite difficult to solder. A pigtail reduces the work of soldering.
XLR connectors are as old as the electric bikes. Their metallic cases serve well in preventing disengagement even with an accidental knock or drop. But this may also work against the connector as the metal housing increases the risk of shorting incase of a loose wire.
They have unmatched moisture resistance and come with a varied number of pins. Connectors with more pins are larger in size.
Manufactured by Amass, XT60 is a heavy-duty ebike battery connector that can handle huge currents of more than 100 amps without melting. Its compact size and low asking price makes it many ebikers’ favorite. Unlike other connectors that require crimping, XT60 must be soldered. It also doesn’t support arcing connections. These two are its primary limitations.
Similar to XT60, this connector is designed by Amass. As an upgrade to the smaller XT60 model, it has 4.5-milimeter bullet pins that impart the ability to handle higher currents. Fitted with an in-built precharge resistor, your battery is protected against sparking that commonly occurs following a capacitive-load battery plug-in.
Available in different pin sizes of between 2.5-8mm, these connectors have varying current handling capacities. You can combine the different genders of this connector in a polarized housing to a single easy-to-use connector. Its moisture resistance almost equals that of the premium XT90 connector.
Which 18650 battery is best for an e-bike?
There are a lot of different 18650 batteries on the market, and it can be tough to know which one is best for your e-bike. In general, you’ll pay attention to a battery’s capacity (mAh rating), discharge rate (C rating), and compatibility with the e-bike’s controller.
In this article, we delve into the 18650 battery in more detail, battery specs, and how to identify the best 18650 battery for your e-bike.
What is a 18650 Battery?
A 18650 battery is a lithium-ion battery that can be recharged. The 18650 designation comes from the physical dimensions of the battery, which are 18 mm in diameter and 65 mm in length. The 0 represents the cylindrical shape of the battery.
18650 is one of the most common types of lithium-ion batteries. They are used in a wide variety of devices, including laptops, vapes, flashlights, and light electric vehicles.
Light electric vehicles such as e-bikes prefer 21700 and 18650 batteries.
How to Choose the Best 18650 Battery for Your E-bike
When choosing battery packs for your electric bike, you’ll want to consider the main factors:
Capacity
The capacity of a battery is measured in milliampere-hours (mAh). The higher the mAh rating, the more energy the battery can store. A higher capacity lithium-ion rechargeable battery will give you a longer range on your bike. A higher capacity also means that the battery will take longer to charge.
Continuous Discharge Rating
The discharge rate of a 18650 battery for an e-bike is measured in terms of continuous current (C). A higher C rating means that the battery can provide more current for a longer period without being damaged.
Higher Continuous discharge ratings are important if you’ll be using your bike for high-performance applications, such as racing or off-road riding.
Compatibility
It’s important to make sure that the 18650 lithium-ion batteries you choose are compatible with your bike’s controller.
Other factors that can guarantee you a good pack of li-ion for your e-bike include:
18650 e-bike cell manufacturers
Some 18650 battery brands are better than others in terms of quality and performance including continuous discharge rating.
There are many brands of 18650 batteries from reputable manufacturers, such as:
Panasonic 18650 lithium-ion batteries are among the most popular on the market. They are known for their high quality, good prices, and performance.
LG Chem 18650 is also very popular. They are known for their high energy density and long life.
Samsung SDI
Samsung 18650 is common in laptops and other devices. They are known for their high quality and reliability.
Sony 18650 is also common in laptops and other devices.
CATL is known for manufacturing high-quality 18650 lithium-ion. They are among the best batteries on the market with good prices.
BYD is a Chinese battery manufacturer. They are known for their good quality and competitive prices.
Toshiba 18650 li-ion are also common in laptops and other devices. They are known for their high expectancy and more power.
A123 Systems
A123 Systems is known for its high-quality 18650 li-ion. They are used in a wide variety of applications, including electric vehicles, digital cameras, and vaping devices amongst other devices.
18650 battery chemistry
The chemical composition of 18650 batteries is very important in choosing a rechargeable battery. The chemical composition includes:
Each of these chemistries has its advantages and disadvantages.
Lithium iron phosphate (FePO4) is the most stable of the four chemistries. It has a very low rate of self-discharge and is not susceptible to thermal runaway. However, LiFePO4 has a lower energy density than the other chemistries.
Lithium nickel cobalt aluminum oxide (NCA) lithium battery comes with a high power density and good stability. It is one of the most popular battery types on the market. It is quite affordable with a low continuous discharge rating.
Lithium nickel cobalt magnesium oxide (NCM) batteries are the most popular type of lithium battery on the market. They are affordable, have a long cycle of life, and are very stable. NCM is available in a variety of voltages, ranging from 3.6 volts to 4.2 volts.
The 18650 e-bike battery voltage
18650 batteries come in a variety of voltages. Your choice of 18650 e-bike battery voltage will ultimately depend on the voltage of your bike.
The e-bike battery voltage you choose will also affect the amount of power your bike has. A higher voltage battery will give your bike more power, while a lower voltage battery will give your bike less power.
Features of the 18650 battery packs for e-bike
Some 18650 batteries come with built-in protection circuits Multi-function Protective Circuit Board (PCM). PCM is used to protect the cells from overcharging, over-discharging, overcurrent, and short circuits.
Overcharging protection: When the cell charging voltage reaches a certain voltage, the charger will stop supplying current to prevent overcharging.
Over-discharge protection: When the cell voltage drops below a certain voltage, the device will stop using the cell to prevent damage from over-discharging.
Overcurrent protection: If the current exceeds a certain A, the PCM will shut down the circuit to prevent damage from overcurrent.
Short circuit protection: If a short circuit is detected, the PCM will shut down the circuit to prevent damage from a short circuit.
Cell balancing: The PCM will equalize the voltage of all the cells in the pack to prevent one cell from being over-charged or over-discharged.
Temperature protection: The PCM will shut down the circuit if the temperature gets too high to prevent damage from overheating.
Your budget
The price of an ebike battery can vary depending on the brand, capacity, discharge rate, and other features. Choose the battery that fits your budget and needs rather than just an expensive battery.
The durability of the 18650 battery for the e-bike
The 18650 should be of high quality and durable. This will save you money in the long run as you will not have to replace it often.
The battery should also be able to withstand extreme temperatures and maintain the bike’s power. This is important as the battery will be exposed to different weather conditions.
The Tritek 18650 e-bike battery pack can withstand temperatures as low as.20 degrees Celsius and as high as 60 degrees Celsius. This makes it a great choice for those who live in areas with extreme temperatures.