Audi 48 Volt Micro Hybrid System Explained

Audi 48 Volt Micro Hybrid

Today’s cars use more electricity than their predecessors – lots more. And it’s not just propulsion motors putting a strain on cars’ electrical systems. It’s also “convenience systems for dynamic chassis control,” according to Audi.

The solution, says Audi, is to change from traditional 12 volt systems to a 48 volt format. That will allow such things as electric turbochargers that spool up to speed instantly, giving better acceleration and greater efficiency. Audi claims such a device can increase fuel economy by nearly 10%, meaning that a car that gets 40 mpg today could see that number rise to 43.5 mpg. That’s a significant gain, considering that manufacturers today are working overtime to find ways to boost fuel economy by a few tenths.

The key to the system is a 48 volt lithium-ion battery mounted in the rear of a car and fed by a beefed up alternator. Audi already has two running prototypes, an A6 sedan and an RS5 coupe, both of which feature an electric turbocharger along with their 48 volt systems. Audi has also signed a contract with LG Chem of Korea to supply the 48 volt micro hybrid batteries and larger batteries for its PHEV cars and future electric cars in a deal worth hundreds of millions of dollars.

Audi is focusing on 48 volt systems because that is the maximum voltage permitted before additional safety systems have to be added to cars to protect occupants from electrical hazards. Those systems add weight and cost to the finished cars, two things manufacturers are anxious to avoid.

If Audi’s vision for the future is accurate, we may soon see the end of the 12 volt battery in our cars and trucks. That wouldn’t be a bad thing, it seems.

Steve Hanley

Closely following the transition from internal combustion to electricity. Whether it's cars, trucks, ships, or airplanes, sustainability is the key. Please follow me on Google + and Twitter.