Direct current system storage battery pack external charger independent charging method and system

The invention discloses an independent charging method and system for an external charger of a direct current system storage battery pack. The method comprises the following steps: respectively configuring two storage battery packs for two sections of direct current bus power supply systems; direct-current screen cabinets are respectively arranged on the two sections of direct-current bus power supply systems; laying a power supply cable between the direct-current screen cabinets and an external charger power supply alternating-current side power supply input cable; carrying out a capacity check test on the direct-current storage battery pack, and after the test is finished, realizing charging of the storage battery pack by an external charger through knife switch switching; and after charging is completed, the storage battery group is recovered to return to the direct-current bus through knife switch switching. According to the method for charging through the external charger, the problem that the voltage fl