Chevrolet will unveil its second-generation Volt extended-range electric car at the 2015 Detroit Auto Show in January, but it appears the automaker just couldn’t help itself from dropping a few details early. Prototypes spotted in the wild show only evolutionary changes for the exterior, but underneath the sheet metal the changes will be much more dramatic.

The new Volt, which arrives as a 2016 model and is based around General Motors Company’s [NYSE:GM] new D2XX compact car platform, will feature a second-generation Voltec extended-range electric powertrain. According to Chevy, the changes made to the powertrain are based on driving behaviour data collected from owners of the current Volt.

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For example, it was determined that 80 percent of miles driven by Volt owners were without gasoline (Chevy originally estimated this figure to be about 75 percent). In response, Chevy has made the second-gen Voltec system more efficient, resulting in greater electric-only range as well as less fuel consumption when the range-extender is in use.

2016 Chevrolet Volt spy shots

2016 Chevrolet Volt spy shots

For the 2016 Volt, the lithium-ion battery has 20 percent extra capacity on a volume basis, as well as fewer cells. This has allowed designers to reduce the battery’s mass by 30 pounds while also changing the packaging to help lower the center of gravity. The battery still forms a T shape instead of the flat-pack design favored by Tesla Motors [NSDQ:TSLA].

The car’s dual electric motors were also made more efficient and refined. The new drive unit is said to be between 5 and 12 precent more efficient than the unit it replaces, and it’s about 100 lbs lighter too. This is because it can use either a single motor or both, depending on power demand.

Furthermore, the Traction Power Inverter Module, which manages power flow between the battery and the electric drive motors, has been directly built into the drive unit to reduce mass, size and build complexity while further improving efficiency. And if that wasn’t enough, the 2016 Volt is also said to have a 20 percent improvement in acceleration compared to the outgoing model thanks to the new drive unit.

2016 Chevrolet Volt powertrain

2016 Chevrolet Volt powertrain

The final key change is the adoption of a 1.5-liter four-cylinder engine instead of the outgoing model’s 1.4-liter unit. The engine, which features direct fuel injection, a 12.5:1 compression ratio, cooled exhaust gas recirculation and a variable displacement oil pump, is said to be both more efficient and more powerful than the unit it replaces.

Final estimates for range and efficiency will be announced at the 2016 Chevy Volt’s debut in Detroit. For an in-depth look at the new Volt’s hardware, head over to our sister site Green Car Reports.

Note, while the original Volt was sold in Europe as the Opel Ampera, the second-generation model won’t make it over. That doesn’t mean Opel is giving up on electric cars, as the automaker’s CEO Karl-Thomas Neumann has confirmed that a new Opel electric will be launched in the near future.


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