CHARGING METHOD, CHARGING DEVICE AND CHARGING SYSTEM FOR POWER BATTERY

A charging method and a charging device (100) for a power battery, which can improve the charging efficiency. The charging method is applied to a charging device. The charging device comprises N energy storage units (110, 120) connected in parallel. Each energy storage unit comprises an energy storage battery (111, 121) and a first DC/DC converter (112, 122) connected to same. Each charge cycle of the charging device comprises a stage in which a power battery (210) is charged, and a stage in which the power battery discharges the N energy storage units. The charging method comprises: obtaining a first parameter in each energy storage unit in a discharging stage; determining, according to the first parameter, a first current output by the first DC/DC converter in each energy storage unit, the first current being inversely proportional to the first parameter in the energy storage unit; and sending the first current to the first DC/DC converter, so that the energy storage battery receives, according to the first current, the electric quantity released by the power battery by means of the first DC/DC converter.