Battery Disconnect Unit

Application description

The Battery Disconnect Unit, or BDU, is a sub-unit inside/outside the battery pack in high-voltage electrical or hybrid systems.
It can be installed in the battery housing either in the “chocolate bar” in the cell pack or on top of the battery housing (so-called “penthouse” location).
This sub-unit is responsible for monitoring, activating, and deactivating the high-voltage battery system.
It (dis-)connects the battery to the vehicle’s high-voltage powertrain and charging systems. It also performs overcurrent / short circuits detection enabling related safety interruptions.


Key Facts

  • Space-saving
  • Easy installation and integration
  • Good heat dissipation
  • Good electrical insulation



  • Localized HV interfaces or Plug-type HV-connectors
  • Small volume design:
    • Weight: 5 kg
    • Volume: 6 liters
  • Different contactor and switch-off components:
    • Main contactors / Contactors for DC charging
    • Pre-charge circuit
    • HV fuse
    • Pyro Fuse or Pyro Switch
  • Customization of various battery designs
  • Voltage, current and temperature measurements
Download the product sheet

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