Abstract:The new energy industry is rapidly emerging with the support of national policies and industrial trends. Large lithium battery modules are more and more widely used, which are generally made of multiple small single cells in series. Due to process differences, these cells are directly unbalanced after a long time of work. If they are replaced directly, the cost is very high. In most cases, the unbalanced lithium battery modules can be balanced and repaired. At present, the balancing strategy used by most balancing devices has a long balancing time. The lithium battery equalization strategy based on dynamic internal resistance tracking studied in this paper introduces the detection of line resistance and internal resistance on the basis of the traditional constant current charge-discharge equalization strategy. Based on the dynamic changes of the line resistance and internal resistance and the real-time characteristics of the charge and discharge of the cell, the output voltage of the equalization module is compensated, so that the voltage of the equalization module always follows the change of the cell voltage, and the cell is basically in the state of constant current charge and discharge. By comparing the real battery, it can be concluded that the dynamic following equalization strategy can improve the equalization efficiency under the premise of ensuring safety.