The basic principle of the active equalization technology is to use the ultra-pole capacitor as a temporary energy storage medium, charge the battery with the highest voltage to the ultra-pole capacitor, and then release the energy from the ultra-pole capacitor to the battery with the lowest voltage. The cross-flow DC-DC technology ensures that the current is constant regardless of whether the battery is charged or discharged. This product can achieve min. 1mV precision while working. It takes only two energy transfer processes to complete the equalization of the battery voltage, and the equalization efficiency is not affected by the distance between the batteries, which greatly improves the equalization efficiency.