Introduction to the characteristics of lithium-ion battery charging and parallel charging

Lithium-ion battery charging method 1. When charging the lithium-ion battery, the charger is best to choose the original special charger, otherwise it will affect or damage the polymer lithium-ion battery. 2. It is best to charge the lithium ion battery in slow charging mode, try to prevent fast charging, repeated charging and discharging will also affect the life of the lithium ion battery. 3. Prevent charging at excessively high temperatures. If the lithium battery is used in an environment higher than the specified operating temperature, that is, 35C or higher, the battery's power will continue to decrease, that is, the battery's power supply time will not be as long as usual. 4. Prevent charging at too low temperatures. If the lithium battery is used in a low temperature environment, that is, below 4C, the battery life will also be reduced. The original lithium battery of some mobile phones cannot even be charged in a low temperature environment. 5. Before the lithium ion battery leaves the factory, the manufacturer has carried out the activation process and pre-charged, so the lithium ion battery has a residual battery, and the lithium ion battery is charged according to the adjustment period. This adjustment period requires 3 to 5 full charges. Discharge. 6. Before charging, do not discharge the lithium-ion battery, because improper discharge will damage the battery. When charging, try to charge slowly and reduce fast charging methods; the time should not exceed 24 hours. The chemical substances inside the battery will be fully activated after three to five full charge and discharge cycles to achieve the best use effect. 7. Li-ion batteries must use special chargers, otherwise they may not reach saturation and affect their performance. After charging, it should be prevented from being left on the charger for more than 12 hours, and the battery should be separated from the mobile electronic product when it is not used for a long time. Parallel charging characteristics of lithium-ion batteries The purpose of parallel charging of lithium-ion batteries is to increase capacity. Therefore, parallel charging of lithium-ion batteries also has different design features compared with single-cell lithium-ion batteries. This is mainly reflected in the charging current design and parallel batteries. Consistency. The characteristics of parallel lithium-ion batteries are: the voltage remains the same, the battery capacity is added, the internal resistance is reduced, and the power supply time is extended. The core content of parallel charging is the size and purpose of parallel current. According to the parallel theory, the main circuit current is equal to the sum of the currents of the branches. Therefore, the n-cell parallel lithium-ion battery that has been combined into a battery pack must achieve the same charging efficiency as a single-cell battery, and the charging current should be n lithium-ion battery currents Sum, this design is reasonable under the formula of Ohm's law: Iu003dU/R. However, the internal resistance of the batteries in parallel will also change. According to the parallel internal resistance formula, the total internal resistance of two parallel lithium-ion batteries is equal to the ratio of the product of the internal resistance of the two batteries and the sum of the internal resistance. Decrease as the number of parallel batteries increases. Therefore, the efficiency of parallel charging of lithium-ion batteries can be realized on the basis that the current is less than the sum of the currents of n parallel lithium-ion batteries. The parallel connection of lithium-ion batteries should pay attention to the consistency of the battery, because the poorly consistent parallel lithium-ion batteries will fail to charge or overcharge during the charging process, which will damage the battery structure and affect the life of the entire battery. Therefore, when choosing batteries in parallel, it is necessary to prevent the mixing of lithium-ion batteries of different brands, different capacities, and different degrees of new and old. The internal requirements for battery consistency are: lithium-ion battery cell voltage difference ≤10mV, internal resistance difference ≤5m, and capacity difference ≤20mA. In fact, after lithium-ion batteries are connected in parallel, there will be a charging protection chip to protect the lithium-ion batteries. When making parallel lithium-ion batteries, lithium-ion battery manufacturers have fully considered the changing characteristics of lithium-ion batteries after parallel connection, which is also in accordance with the above Current design and battery cell selection are required. Therefore, users should follow the instructions of parallel lithium-ion batteries to charge step by step to prevent possible damage to the battery caused by incorrect charging. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete it.