Battery Management System Control Unit Basic Function - GF47.70-P-9895A

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Model All (CAR)

with code 63B (On-board xEV charging socket Combo2/Type2)

Model All (CAR)

with code 64B (On-board xEV charging socket Chademo/Type1)

Model All (CAR)

with code 65B (On-board xEV charging socket China Standard GB/T)

Model All (CAR)

with code 66B (On-board xEV charging socket Combo1/Type1)

Fig 1: Battery Management System Control Unit Components Location - Model All (CAR) With Code 63B, 64B, 65B, 66B

Courtesy of MERCEDES-BENZ USA

A hybrid vehicle is shown

Location

The battery management system control unit (2) is integrated in the HV battery module (1).

In electric vehicles (depending on the model), two battery management system control units (2) and one battery management system gateway control unit can be installed.

Task

The battery management system control unit (2) is connected to the network architecture of the vehicle.

The battery management system control unit (2) determines and constantly monitors the following data:

Interlock circuit
High-voltage battery voltage
High-voltage battery current flow
Temperature of high-voltage battery
State of contactor
High-voltage on-board electrical system insulation monitoring status

For this purpose, the battery management system control unit (2) processes the following information among other things:

Circuit status
Interlock circuit
Crash signal
12 V on-board electrical system battery voltage/current
Outside temperature
Vehicle speed
Engine running, engine speed, engine load (hybrid vehicles) status
Deep discharge protection status
High-voltage charging voltage/charge current
Status of charger
Charging cable connector status

The battery management system control unit (2) processes these input variables and transmits the following information among other things:

High-voltage battery voltage/current
High-voltage battery cell voltage
High-voltage battery charge level
Temperature of high-voltage battery
Max. charge/discharge current
Internal resistance during charging/discharging of high-voltage battery
Status of the contactor
Detection of a thermal event
Fault messages