Today, electric bicycles are increasingly moving toward high-end intelligence. The development and manufacturing technology of electric bicycles is constantly improving, and the production process is becoming more and more mature. But there is a drawback, but it has always restricted the development of electric vehicles, that is the core of electric bicycles – “lithium battery”!
High-tech is constantly developing and innovating. In the field of lithium battery research and development, lithium batteries have quickly occupied half of the battery types by virtue of various advantages, and have become the main force in the power market and energy storage products. The development of lithium batteries is inevitable, and the popularity of lithium batteries in the energy storage market has been very widespread. Take the battery to compare, lithium battery is superior in terms of weight, or lithium battery from the volume. Many people are worried about the life of lithium batteries, because the life of lead-acid batteries (referred to as batteries) is about 3 years, so consumers are still concerned about the life of lithium batteries.
A “lithium battery” is a type of battery using a lithium metal or a lithium alloy as a negative electrode material and using a nonaqueous electrolyte solution. Due to the very active chemical properties of lithium metal, the processing, storage and use of lithium metal are very demanding on the environment. Therefore, lithium batteries have not been used for a long time. With the development of science and technology, lithium batteries have become the mainstream now. In theory, the “lithium battery” has a cycle life of about 600 times. Please see below for details!
Can lithium battery life for electric bicycles last for 5 years?
The correct statement: lithium battery life can not be used for 5 years and the number of completion of the charging cycle, and the number of charging is not directly related. A simple understanding, for example, a lithium battery used only half of the electricity on the first day, and then fully charged. If it is still the next day, it will be charged in half, and it will be charged twice in total. This can only be counted as one charging cycle, not two. Therefore, it is usually possible to complete a cycle after several charges. Each time a charge cycle is completed, the amount of power is reduced a little. However, the reduction is very small. After a high-quality battery has been charged for many cycles, it will still retain 80% of the original power. Many lithium-powered products are still used after three or four years, which is why. Of course, the life of the lithium battery will eventually need to be replaced.
It is said that the theoretical life of lithium battery is generally about 600 charge cycles. Assuming that the power supplied by a full discharge is Q, if the power consumption is reduced after each charging cycle, the lithium battery can provide or supplement a total of about 600 Q of power during its lifetime. From this we know that if you charge 1/2 each time, you can charge about 1000 times; if you charge it with 1/3 each time, you can charge about 1500 times. By analogy, if you charge randomly, the number of times is variable. In short, no matter how charged, the total amount of power added to about 600Q is constant. Therefore, we can also understand that the life of the lithium battery is related to the total charge of the battery, regardless of the number of times of charging. The effect of deep deep charge and shallow charge on lithium battery life is not much different.
In fact, shallow shallow charge is more beneficial for lithium battery. Only when the power module of the product is calibrated for lithium battery, it is necessary to deep charge. Therefore, products that use lithium-ion power supply do not have to be constrained by the process. Everything is convenient and can be charged at any time without worrying about affecting life.
The loss of lithium battery capacity can be expressed during the charging, discharging and self-discharging of lithium batteries:
1. When the lithium battery is added once in a complete cycle, the charging time will be reduced a little. The charging platform of the lithium battery is in the range of 3.7V~4.2V, and the charging capacity accounts for more than 90% of the total charging capacity at this stage. As the number of cycles increases, the voltage rises faster, and the capacity of the lithium battery decreases after the battery is fully charged.
2. The discharge platform of lithium battery is 4.1V~2.75V (the minimum discharge voltage of single-cell lithium battery is 2.75V). The discharge capacity accounts for more than 90% of the total capacity at this stage. With the increase of the number of cycles, the discharge of lithium battery As the platform is lowered, the discharge capacity is also reduced.
3. The ratio of the self-discharge of the lithium battery to the total power of the lithium battery increases as the number of cycles increases, but the lithium battery discharge platform is accelerated.
The reduction in the lifespan of lithium-ion batteries is characterized by capacity decline. The life of lithium batteries is limited. This is the same as the development of anything. Capacity decline is a manifestation of quantitative change to qualitative change. It can be seen from this performance that the method of extending the life of the lithium battery is undoubtedly considered from the viewpoint of scientific charge and discharge and reduction of self-discharge, and the loss during use directly affects the life of the battery.
If you want to maximize the life of your lithium battery, then consumers must understand the three taboos of “lithium battery”!
First, temperature: lithium batteries are afraid of high temperatures.
Second, high current: For example, 18650 battery is 3C discharge, your electric car is 8000W, the battery used is lower than your electric vehicle discharge current, which will cause the lithium battery temperature to be too high, the current is too large and the life is shortened. There will also be cases where the drum kit is scrapped. If your electric car is very powerful and very fast, it is recommended to choose 18650 batteries with 10C current. It is obviously very important to choose the right battery core!
Third, full power storage: Take ternary lithium, the full power is 4.35V, the current protection board on the market is 4.2V to cut off the charge, so many people buy electric vehicles lithium battery said no nominal The capacity is large, in fact, this is the reason. Generally, the lithium battery of the electric vehicle is stored for a long time, and the TV with half of the 50 is the best. For example, if you buy a new mobile phone, many of them are powered by 50%. If the full storage time is long, the lithium battery capacity will be reduced. Except for lithium iron phosphate and lithium titanate, these two types can be stored at full power. It is also necessary to pay attention to the selection of a better quality protection board. The biggest taboo for lithium batteries is overshoot and over discharge. Scrap, overshoot must be sterilized.