1. Nowadays, many people prefer to buy electric bikes with lithium batteries. There are many types of lithium batteries. What is the difference?
Nowadays, the more widely used lithium batteries on the market are mainly divided into three categories: ternary lithium ion batteries, lithium manganate batteries, and lithium iron phosphate batteries. Among them, ternary lithium batteries and lithium iron phosphate batteries are more widely used. From a safety point of view, the safety of lithium iron phosphate batteries and lithium manganese oxide batteries is higher than that of ternary lithium batteries.
Ternary lithium ion batteries generally use lithium nickel cobalt manganese or nickel cobalt aluminate lithium ion batteries as cathode materials. Different from other lithium-ion batteries, the capacity of ternary lithium-ion batteries is higher than other lithium-ion batteries, and the cycle performance of ternary lithium-ion batteries is better than that of ordinary lithium cobalt oxide lithium-ion batteries. The nominal voltage of the ternary lithium-ion battery is 3.7V, and the working voltage is 2.75V~4.2V. But the thermal stability of ternary lithium is poor, so the safety is not as good as lithium iron phosphate and lithium manganate.
Lithium manganate battery refers to a battery that uses lithium manganate material for the positive electrode. The nominal voltage of lithium manganate battery is 2.5~4.2V. Lithium manganate battery is widely used because of its low cost and good safety. Lithium manganate batteries have the advantages of low cost, strong stability, and strong low-temperature performance, but they also have the disadvantages of low energy density, poor high-temperature performance, and faster attenuation.
Lithium iron phosphate battery refers to a lithium ion battery that uses lithium iron phosphate as the positive electrode material. The lithium iron phosphate power battery has a cycle life of more than 2000 times, and it can be used for 2000 times with standard charging (5 hours rate). The theoretical service life will reach 7 to 8 years, and it is currently the preferred battery cell type with both safety and cost performance.
2、The life of lithium batteries is related to the followings.
The charging temperature of the lithium battery is 0℃～45℃, and the discharge temperature of the lithium battery is -20℃~60℃.
Lithium batteries have no memory effect and can be charged as they are used, but it should be noted that lithium batteries cannot be over-discharged. Over-discharge will cause a very large capacity loss.
The safe working voltage range of the ternary lithium battery is 2.75~4.2V, and the safe working voltage of the lithium iron phosphate battery is 2.5~3.65V. If the lithium ion in the battery is lower or higher than this voltage range, it will become very unstable and even cause an accident. In order to ensure that the battery is in a safe range, a dedicated charger is required, and lead-acid chargers cannot be used for charging.
When the lithium battery is left unused for a long time, it needs to be charged and discharged every six months to restore its original performance.
Before using the lithium battery, check whether it meets the requirements of the load. Using it under conditions that cannot meet the load requirements or high current (over 1C) will damage the battery or shorten its service life.
Avoid frequent use of lithium batteries in high or low temperature environments. It is best to be at room temperature, as the temperature has a great influence on the characteristics of the lithium battery.
3、How can lithium battery electric bikes be used safely?
The low-priced lithium batteries on the market are basically assembled by disassembling cells and unqualified cells, which poses a great safety risk. Some unscrupulous merchants even do not install protective plates for lithium battery packs in order to seek huge profits. This is one of the main reason leading to safety problems in lithium batteries.
4. How to use the lithium battery correctly when buying a lithium battery car?
Use a lithium battery special charger that matches the battery pack.
Do not use lithium battery packs on illegally modified high-power electric bikes.
Do not expose the lithium battery to high temperature (≥65℃) for a long time.
As the battery pack temperature is high just after riding the electric bike, please allow it to cool naturally for about half an hour before charging it.
The use of lithium batteries at 20% to 90% SOC can greatly extend the life of the lithium battery pack.
It is normal for lithium batteries to have a certain reduction in the driving mileage of electric bikes when the temperature is lower than 15°C in winter. When the temperature returns to around 25°C, the driving mileage of the electric bike returns to normal.