The on-board network of a vehicle includes the systems power generation, energy storage, consumers and all associated cables and wires in between.
The car battery is an essential component of the electrical system. The 738031 "Battery monitoring" educational panel contains the "diagnostic interface for data bus" with the battery's energy management functionality. This consists of software and the battery data module (BDM), directly on the vehicle battery's negative pole and connected to the diagnostic interface over a LIN bus line.
The BDM determines the battery's state with sensors recording the battery's current, voltage and temperature. This continually calculates the battery's state of charge and state of wear using, among others, battery characteristics stored in the control unit.
The standby current keeps the battery voltage from declining below a minimum value needed to start the vehicle. For example, operation of the auxiliary heating is disabled, and a display on the instrument cluster informs the driver.
The dynamic management distributes the energy generated while driving to the individual loads. This is especially important if the energy does is not sufficient for the demand because of the number of loads (seat heater, lights, rear window).