What are the general characteristics of parallel charging of lithium battery packs?

Can lithium batteries be charged in parallel? When the capacity of a single lithium battery cannot meet our needs, what will we do? Regarding this problem, some people choose to do it themselves in parallel to increase the capacity, while some people choose to buy a larger capacity lithium Replace it with a battery pack. It is feasible to connect multiple single lithium batteries in parallel by a self-acting hand. It is physically feasible to connect lithium batteries with the same voltage, equivalent capacity and small difference in internal resistance. However, before connecting, all lithium batteries must be charged or discharged to reach the same voltage and then connected. For safety and the service life of the lithium battery, it is best to add an independent protection board to each lithium battery. Coupled with a protection board, it can protect a certain battery or multiple lithium batteries from overcharging and over-discharging, and can prevent chain reactions from occurring. Precautions for parallel connection of lithium batteries If lithium batteries are to be connected in parallel, the consistency of the batteries is an issue worthy of attention. Because the parallel lithium battery pack with poor consistency is likely to fail to charge or be overcharged during the charging process. In this way, the structure of the lithium battery will be greatly damaged, which will affect the service life of the entire group of lithium batteries. Therefore, most of the lithium batteries connected in parallel in the lithium battery pack are processed in the same batch with the same capacity. If you want to connect lithium batteries in parallel by yourself, you must pay attention to maintaining battery consistency. It is best to meet the following requirements: lithium battery cell voltage difference ≤10mV, internal resistance difference ≤5m, and capacity difference ≤20mA. Charging characteristics of parallel lithium battery packs The overall voltage does not change, the capacity of the lithium battery packs will add up, the internal resistance will be reduced, and the delayed power supply time will be prolonged. The core content of parallel charging is the current size after paralleling and its use effect. According to the parallel theory, the current of the main circuit is equal to the sum of the currents of the branches. Therefore, the n-cell parallel lithium batteries that have been combined into a battery pack must achieve the same charging efficiency as a single-cell battery, and the charging current should be the sum of n lithium battery currents , Under the formula of Ohm’s law: Iu003dU/R, this design is reasonable. 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 batteries is equal to the ratio of the product of the internal resistance of the two batteries and the sum of the internal resistance. The parallel resistance will follow the parallel connection. The number of batteries increases and decreases. Therefore, the efficiency of parallel charging of lithium batteries can be achieved on the basis that the current is less than the sum of the currents of n parallel lithium batteries. If you are buying a lithium battery pack in parallel, there is not much to pay attention to when charging, as long as you charge it according to the normal charging method. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: What is the important method of repairing lithium iron phosphate battery pack