The battery is one of the most important components of an e-bike, and it's also the most expensive. The battery is the decisive factor in determining how long the bike can be used without recharging, how long it will work, how much weight, etc. In general, when you choose an electric bicycle, the battery is the component you must pay the most attention to.

 

What are the types of electric bicycle batteries? How are they different?

Choosing a good battery directly determines its efficiency and how far you can go on a single charge. Even at the same size and weight, different batteries will work very differently depending on the type and construction. All batteries have their own characteristics, including capacity, voltage, size, weight, charging time, and total battery life. 

 

 

Voltage 

Most e-bike kits have a specific voltage range. A typical 36V e-bike requires a battery that can deliver 30V to 42V. A 36V 42V battery pack is 100% charged and holds as much energy as possible; When the voltage is 30V, the power supply should be turned off and stopped to avoid permanent damage. More about BMS(Battery Monitoring System). The common number "36V" is the average operating voltage, sometimes called the nominal voltage. Voltage is measured in volts (V) and is used to describe the speed at which electrons move. Higher voltage = Faster speed!

 

Capacity

It's the amount of energy a battery can store. This is the main feature of any battery. The unit of measurement is ampere-hour (Ah). This value is a measure of the constant amperage (c-rate) that the battery can sustain for 1 hour. Double the current for half an hour. Or cut the amperes off for two hours, etc.

The battery has a certain number of charge and discharge cycles, after which the capacity begins to decline proportionally. If the battery is discharged by 10% and then recharged, it is considered to have used one cycle.

The actual life of the battery is determined by the number of cycles, which depends on the working conditions of the battery. The longer the battery is discharged, the fewer cycles can be expected.

 

Lead (gel) batteries

It's the oldest variant, used less and less every year. There are many reasons for this, the main one being low capacity. Gel batteries are heavy, and batteries make the bike's structure very heavy. In addition, it charges slowly: it takes 8-10 hours to fully charge. The battery life is also very short, only 150-200 cycles.

 

Li-ion battery (Li-ion) 

The most popular and ideal battery type for electric bicycles today. Lithium batteries are the best combination of total weight and capacity. Lithium-ion batteries have the highest specific capacity of any existing type, which is their main advantage. Lithium-ion batteries have no "memory" effect.

Disadvantages of this type include sensitivity to temperature conditions and inability to charge quickly. Lithium-ion batteries are also sensitive to overheating and require controlled discharge patterns. With the passage of time, people's abilities will gradually age and lose. The number of cycles is about 400 times, which is 2.5 times that of lead-acid batteries.

Lithium-ion batteries for electric bicycles must be specifically designed due to the presence of a battery management system (BMS) within the pack. This piece of circuitry must be set appropriately to control the amount of current draw required by the motor and to limit excessive discharge capacity.The BMS is also important for balancing cell charge between the individual cells within the battery to maintain battery life over time.

 

Li-Po 

This kind of battery is mainly popular among mobile phone manufacturers, because it can not drive electric bikes, nor can it withstand the shock and vibration during riding.
It is designed for electric vehicles, which cannot possibly produce such vibrations. It is often used in model aircraft because weight is important.
This is the most dangerous battery in terms of ignition! Under adverse conditions (short circuit, BMS failure, accident), there is a high risk of fire.

 

LiFePo4 

This is a relatively new but already popular type of battery. The advantages of this battery include frost resistance (it can operate at temperatures as low as -30 degrees Celsius without loss of capacity) and the ability to charge quickly. This battery has the highest number of full cycles, about 1,000. It is less susceptible to aging than a typical lithium-ion battery. It also has no memory effect. The disadvantages of LiFePo4 batteries are low specific capacity and high cost.

 

Frequently Asked Questions

• How can I avoid destroying the battery?

First, pay attention to the battery on/off system. Famous manufacturers use "sleep mode" in their batteries. You activate the battery mainly by pressing a button or turning on the e-bike on the control display. Once you turn off the e-bike, the battery will "sleep" on its own after a few hours, so the power to the BMS system will also be turned off. If you are riding, you will need to press the button again to activate the battery.

• How do I store the battery in winter?

It's easy to store batteries in the winter. Basically, it is enough to charge the battery to 50% and store it in a cool place. It is best to store the battery outside the e-bike to prevent unnecessary activation.

• The batteries heat up during charging, is something wrong?

No, it's okay, all types of batteries heat up when they're charged. The same goes for chargers.

• What is the 'memory effect'?

The memory effect occurs when a battery is charged before it is fully discharged. The battery "remembers" the last remaining capacity before the next charge. Therefore, charging the battery before it is fully discharged will shorten the battery's service time. The batteries used in most of our products (Li-ion batteries, Li-ion batteries) have no or very slight memory effects.

• What does self-discharge mean?

If the battery is not used after a full charge, it will gradually lose energy. Lithium-ion batteries and lithium-ion batteries have very low self-discharge values, which fluctuate by up to 5% per month at room temperature. It is useful to check the battery once a month, and if its capacity has dropped below 50%, charge it to around 70%. The idea that deep discharge can extend battery life is completely nonsense!

ChamRider-Battery recommends a few tips for extending the life of your e-bike battery.

Tip 1 – Try not to discharge the battery below 20%.

Deep discharges make the battery difficult to use and reduce its future capacity. Lithium batteries begin to oxidize, which has a negative impact on both capacity and battery life. In case of shutdown (such as winter), it is recommended that the battery be fully charged at least every 90 days.

Tip 2 – Do not charge the battery immediately after riding.

The battery should be cooled before being charged. If we start charging a heated battery, it won't cool down at all, and the battery will degrade much faster.

Tip 3 – Do not fully charge the battery if it is not necessary.

When the battery is charged more than 80% of its capacity (about 40V), the internal resistance of the battery increases and the battery heats up more, which greatly accelerates the degradation process of the battery.

Tip 4 – Avoid extreme temperatures.

High temperatures and frost affect performance and shorten battery life. Do not store batteries outdoors at temperatures below 0ºC. Similarly, we recommend against storing the battery at temperatures above 30 degrees Celsius. Also, avoid parking in direct sunlight for long periods of time.