Battery management system

The invention discloses a battery management system which comprises a lithium battery pack, a sampling module, a control module and a power conversion module, the control module is in communication connection with an upper computer, vehicle-mounted equipment is connected with the control module through a CAN bus, and the voltage, current and surface temperature of the lithium battery pack are directly measured and collected by the sampling module; data collected by the sampling module are sent to the control module, the control module is connected with the power conversion module, the control module sends a control signal to the power conversion module, the internal state of a battery pack is estimated through a battery model, and then control over the battery pack is completed. The battery management system BMS detects each single battery through the control module to obtain battery state parameters, and the control module communicates the state parameters to the control module for state analysis, control an