Views: 8012 Author: RJ Publish Time: 2019-11-13 Origin: RJ
Capacity can be divided into rated capacity and actual capacity. The rated capacity of battery refers to the minimum amount of electricity required or guaranteed to be discharged under certain discharge conditions during the design and manufacture of battery; the actual capacity of battery refers to the actual amount of electricity discharged under certain discharge conditions, which is mainly affected by discharge rate and temperature. Rated capacity means the nominal capacity of the battery. Under the condition of 25 ± 5 ℃, the rated capacity of the battery is calculated by the product of the current value and the discharge time data. In the same group of lithium batteries, the rated capacity difference of single battery should be controlled within a certain range.
2. Consistent internal resistance
It is generally divided into AC internal resistance and DC internal resistance. The daily measurement is AC internal resistance. The internal resistance is mainly composed of electrode material, electrolyte, diaphragm resistance and contact resistance of parts, which is related to the size, structure and assembly of the battery. Under normal circumstances, the battery with small internal resistance has strong discharge capacity of large current and weak discharge capacity of the battery with large internal resistance. The large internal resistance of the resistance will produce a lot of Joule heat, which will increase the internal temperature of the battery, reduce the working voltage of the battery discharge, shorten the discharge time, and have a serious impact on the performance and life of the battery. The unit of internal resistance is Ω. At 25 ± 5 ℃, the AC impedance of the battery is measured by the AC internal resistance tester, and the test frequency of the AC internal resistance tester is 1kHz. In the same battery group, the internal resistance of lithium battery is controlled within a certain range.
3. Constant current ratio is consistent
Constant current ratio refers to the ratio of constant current charge to constant current and constant voltage charge. The higher the constant current ratio, the better the performance of the battery. During capacity sharing, the battery is discharged to the specified voltage at a constant current rate of 3H at 25 ± 5 ℃, and then charged to the specified voltage at a constant current rate of 3H, and charged at this constant voltage until charging stops. The ratio of constant current charge to total charge can be calculated. In the same group of lithium batteries, the single battery shall be of the same constant current ratio grade.
4. Consistent discharge platform
The discharge platform is a feature of the battery discharge curve, that is, the time when the battery is fully charged and discharged to the specified voltage at the rate of 3H. The higher the discharge platform, the better the battery performance. When the capacity is divided, the battery is charged at a constant current rate of 3 hours to a constant voltage charging voltage at 25 ± 5 ℃, and the battery is charged at a constant voltage until the charging stops. Discharge at a rate of 3 h until the discharge is terminated. Record the time when the voltage drops to the specified voltage. In the same group of lithium batteries, the single battery needs the same level of discharge platform.
5. Consistent voltage
Battery voltage refers to the potential difference between the positive and negative poles of the battery, which is divided into open circuit voltage and working voltage. Open circuit voltage refers to the potential difference between the two poles of the battery when the battery is not charged or discharged. If the positive and negative materials of the battery are the same, the open circuit voltage of the battery is the same no matter how big the battery is and how the geometry changes. Working voltage refers to the potential difference between the two poles of the battery during charging and discharging. The charging voltage is higher than the open circuit voltage, and the discharging voltage is lower than the open circuit voltage. Under the same conditions, the higher the discharge voltage, the better the performance of the battery. The voltage is affected by the battery charge, temperature and other conditions, and the unit of voltage is "V". In the same battery group, the voltage of single battery is controlled within a certain range of differential pressure.
6. Battery batch
Consistent batch refers to basically consistent electrical performance of the same type of lithium battery produced with the same batch of materials, process, equipment and time. The same batch of batteries shall be selected for the same group of batteries. If the number of batches is not enough, the adjacent batches of batteries in the same process shall be selected.
As a leading producer of lithium battery industry, RJ has made a breakthrough in the consistency of lithium battery, and its products have received great response in the market and great welcome.