48-Volt Mild-Hybrid System Explained
By
Chris Teague
FCA US LLC
The automotive world may be moving toward electrification, but it will still be many years before full-on EVs become prevalent. In the meantime, automakers are developing better and more refined hybrid and plug-in hybrid vehicles. One type of hybrid that has become more common in recent years is the 48-volt mild-hybrid system. Its use has expanded the performance and efficiency of vehicles from many automakers, and has become a popular way to extract more power from a vehicle without negatively impacting fuel economy.
What is a 48-Volt Mild-Hybrid System?
Mild hybrids, also called 48-volt mild-hybrid systems, are the least electrified version of hybrid powertrains. Designs vary from model to model, but the basic concept and construction are the same. A small electric motor, which can be called an integrated starter generator (ISG), is connected to the engine and works in tandem with the internal combustion unit to provide extra power for acceleration. Automakers use 48-volt systems to boost performance, but they also come with an inherent fuel-efficiency benefit, in that they share the engine’s load in controlled scenarios, helping it save fuel. Some company, such as Volvo, employ mild-hybrid configurations with slightly different components. The Volvo ISG is 42 volts, for instance.