Is Volvo's 48V Mild Hybrid BSG or ISG?

[Luke]

Volvo's 48V mild hybrid is ISG. Benefits of the 48V mild hybrid system: 1. Fuel savings: When the engine is running at low speeds, the 48V mild hybrid system can maintain the operation of the air conditioning. Additionally, the 48V mild hybrid system with a power system can assist the vehicle during startup, using electric power during the most fuel-intensive phase to significantly save fuel. 2. Long battery life: The battery life of the 48V mild hybrid system generally exceeds 5 years. The 48V mild hybrid system uses a 48V battery, which is more advanced in terms of cost and technology compared to a 12V system. The 48V mild hybrid system mainly consists of a motor, battery, and voltage converter. However, the 48V battery is also relatively expensive, so when choosing a vehicle with a 48V mild hybrid system, attention should be paid to battery maintenance.

[KeeganLee]

I've driven quite a few Volvos equipped with 48V mild hybrid systems using BSG technology. This belt-driven starter-generator is mounted on the engine pulley, primarily assisting with engine start-stop and low-speed operation. Unlike Mercedes-Benz C-Class models that use ISG systems, Volvo opted for BSG mainly due to its lower cost and minimal modifications required. That smooth and quiet startup you experience is the BSG at work, eliminating the vibrations from traditional starters. It does help save some fuel in city traffic jams, but pure electric driving like plug-in hybrids isn't possible. If it fails, just replacing the belt assembly is sufficient - much simpler than dismantling the transmission to repair an ISG system.

[ReeseRose]

As a long-time Volvo owner, my XC60 mild hybrid uses the BSG type. Every time it auto-stops at a red light and restarts, I barely feel anything—that's the belt-driven BSG at work. Unlike Audi A8's ISG, which is sandwiched directly between the engine and transmission, the BSG is mounted on the peripheral pulley. The advantage is its simple structure and affordable maintenance, but the motor's small power limits it to assisting the engine with minor tasks. The BSG's limitations become obvious in winter when the heater increases fuel consumption. Volvo's system offers limited performance enhancement, with its greatest value being the seamless start-stop experience.

[RebeccaRose]

The 48V mild hybrid system is divided into BSG and ISG types, and Volvo has chosen BSG across its entire lineup. Simply put, it involves adding an electric motor to the engine's pulley, which costs 30% less than ISG. ISG, which needs to be integrated into the engine's flywheel position, offers stronger power but requires a complete redesign of the powertrain. Volvo opted for quick installation and compatibility, making it suitable for both new and old models. It's truly quiet when starting, but the motor's maximum output of 15 kW is only enough to assist with initial acceleration. Once, while driving uphill on a mountain road, I realized the BSG motor alone couldn't handle the load. If you're aiming for high performance, you might be disappointed, but it's sufficient for daily commuting.