Powertrain Electrification Electric Motors

48V Belt Starter Generator (iBSG)

Last update: 12 Jul. 2024

What is a 48V belt starter generator?

The 48V iBSG* is a belt-driven reversible starter generator, which is fitted in the car engine in place of the alternator and turns the vehicle into a MHEV (Mild Hybrid Electric Vehicle).

It provides up to 6% fuel economy benefits on WLTP cycle compared with a conventional stop-start system. In addition to the alternator and stop-start function, the 48V Belt Starter Generator will ensure the regenerative braking to recover energy during decelaration and braking phase. This energy is stored in a 48V battery in order to be reused to assist the thermal engine and reduce its fuel consumption.

The power module development of the 48V Belt starter generator (iBSG) is done in-house for improved integration.

For higher reliability and better thermal dissipation, the mechatronic design has been optimized with a thermal decoupling between the electric machine and the electronic. The 48V iBSG is now re-used for light electric mobility.


*iBSG = integrated Belt Starter Generator

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What are the 48V belt starter generator benefits?

  • CO2 savings up to 6% on WLTP
  • Torque assist function
  • High re-cranking comfort
  • Complete range of performance with different cooling technologies (air or mixed air/water)
  • Highly standardized product and robust concept based on alternator technologies
  • Easy integration on thermal engine accessory drive

48V belt starter generator specifications

  • Synchronous Claw Pole electrical machine
  • Peak regenerative braking up to 15 kWp
  • Peak mechanical power up to 10 kWp
  • Continuous power @ 1.800 rpm: 1,8 kW
  • Continuous power @ 6.000 rpm: 6 kW
  • Max efficiency > 85%
  • Max torque > 65 Nm
  • More than 1 million Stop/Start operations
  • 6%*

    CO2 benefits on WLTP cycle (Up to*)

  • 40%

    worldwide market share

  • 1.5Mu*

    produced per year (More than*)

Vehicle type

  • Passenger car
  • Bus
  • Truck
  • Robot taxi
  • Motorcycle
  • Bike
  • Droid
  • Off road

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