How does the hybrid engine of the Audi A7 work?

I am interested in learning how the hybrid engine in the Audi A7 works. Can someone explain the mechanics and advantages of this system?

The Audi A7 features a hybrid engine with a 48-volt mild hybrid system. This system uses a lithium-ion battery and a belt alternator starter to assist the traditional internal combustion engine, resulting in improved fuel efficiency and reduced emissions.

Not only does the hybrid engine in the Audi A7 offer improved efficiency and reduced emissions, but it also provides a smoother driving experience with seamless transitions between electric and gas power.