A Guide to the Hybrid Integrated Starter-Generator in Mercedes-Benz Engines 

What is the Hybrid Integrated Starter-Generator (ISG)?  

The Hybrid Integrated Starter-Generator (ISG) is an innovative system that replaces a conventional starter motor and alternator with an electrified motor positioned between the engine and transmission. This system is critical in improving fuel efficiency, reducing emissions, and enhancing driving dynamics.  

Unlike conventional systems, ISG provides electric torque assistance, meaning the engine requires less fuel to perform optimally. This results in smoother acceleration, reduced engine strain, and improved responsiveness. It also enables smooth start/stop functionality, eliminating vibrations when the engine restarts.  

ISG technology is part of the Mercedes-Benz EQ Boost system, a mild-hybrid solution that supports performance while keeping emissions low. This integration ensures a quieter, more refined ride with enhanced energy efficiency. 

Key Benefits of the Hybrid Integrated Starter-Generator (ISG)  

Enhanced Fuel Efficiency- ISG technology assists the engine by providing instant electric torque, reducing fuel consumption during acceleration. This mild-hybrid system optimizes efficiency without sacrificing power.  

Seamless Start/Stop Function- Unlike traditional systems, the ISG allows for virtually undetectable engine restarts, ensuring a smoother and more comfortable driving experience.  

Energy Recuperation- The ISG recovers kinetic energy and stores it in a 48-volt battery during braking. This stored energy is later used to assist the engine, improving overall efficiency.  

Instant Power Boost- ISG provides an extra 20-25 horsepower during acceleration, enhancing responsiveness while maintaining fuel efficiency. This function improves performance without increasing emissions.  

Reduced CO₂ Emissions- By optimizing engine load and utilizing energy recuperation, the ISG significantly lowers carbon emissions, contributing to a greener driving experience.