A battery management system, comprising: an energy storage battery , a power conversion system, PCS, a central monitoring unit , and a direct current converter , wherein the battery management system further comprises a monitoring module and a sampling module , an input terminal of the direct current converter is connected to the PCS , an output terminal of the direct current converter is connected to the energy storage battery , and the direct current converter , the sampling module , and the monitoring module are integrated on a same printed circuit board, PCB; the sampling module is configured to: perform sampling on an operating parameter of the direct current converter to obtain target sampling information, and send the target sampling information to the monitoring module ; and the monitoring module is configured to: receive the target sampling information sent by the sampling module , and send the target sampling information to the central monitoring unit , so that the central monitoring unit determines, based on the target sampling information, target charge power for charging the energy storage battery by the PCS ; and receive a first control instruction sent by the central monitoring unit , and control, according to the first control instruction, the direct current converter to adjust charge power for charging the energy storage battery by the PCS to the target charge power; characterized in that the battery management system further comprises a power obtaining module , wherein the power obtaining module is configured to: generate an induced current based on an actual current in the direct current converter , generate a power supply current by using the induced current, and supply power to the monitoring module ; wherein the power obtaining module comprises a power obtaining transformer, configured to generate an induced current based on an actual current on the direct current converter . the sampling module is configured to: perform sampling on an operating parameter of the direct current converter to obtain target sampling information, and send the target sampling information to the monitoring module ; and the monitoring module is configured to: receive the target sampling information sent by the sampling module , and send the target sampling information to the central monitoring unit , so that the central monitoring unit determines, based on the target sampling information, target charge power for charging the energy storage battery by the PCS ; and receive a first control instruction sent by the central monitoring unit , and control, according to the first control instruction, the direct current converter to adjust charge power for charging the energy storage battery by the PCS to the target charge power; characterized in that the battery management system further comprises a power obtaining module , wherein the power obtaining module is configured to: generate an induced current based on an actual current in the direct current converter , generate a power supply current by using the induced current, and supply power to the monitoring module ; wherein the power obtaining module comprises a power obtaining transformer, configured to generate an induced current based on an actual current on the direct current converter . <EOS>