The battery enters the measuring machine along the assembly line, and the measuring machine simultaneously measures the voltage of a group of batteries. The measurement data is analyzed and compared through PLC. If the measurement result is within the qualified voltage range (factory standard range: 13.10-13.36V) and the pressure difference is ≤ 0.03V, the battery pack will enter the next process through the measuring machine; If at least one set of measurement results exceeds the factory standard range or the same set of data has a large pressure difference greater than 0.03V, the battery pack will be pushed out at the defective product station. This voltage measuring machine can be used for voltage measurement of 4 battery packs, 5 battery packs, and 6 battery packs. Equipment capacity: capable of measuring the voltage of at least 27 batteries per minute.