After the power battery is grouped, it will gradually produce inconsistencies and develop due to force majeure factors such as initial production process and environmental factors. In order to meet the identification requirements of power battery consistency, a fast identification method of power battery consistency is proposed in this paper. Based on the statistical distribution of the outlier detection method, this method calculates and analyzes the cell voltage data of the entire group of batteries to identify the consistency state of the battery pack, extreme cells and their abnormal causes and extreme degrees. The method involves a simple calculation process and a small amount of calculation, which is suitable for daily quick detection. The feasibility and effectiveness of the proposed identification method are verified by examples.