It may be hard to imagine, but the Chevrolet Volt range-extended electric car is about to enter its third model year.

The new 2013 Chevrolet Volt will offer a slightly higher all-electric range, up from 35 to 38 miles. Its base price of $39,995 will not change.

Next year's Volt will also receive a higher EPA efficiency rating, from 94 to 98 MPGe, or Miles Per Gallon Equivalent--a measure of how far the vehicle can travel on electricity with the energy content of 1 gallon of gasoline.

The 2013 Volt will be fitted with a battery pack that holds slightly more energy--up from 16 to 16.5 kilowatt-hours--and the car can draw on 10.8 kWh of that total, rather than the 10.3 kWh available in 2011 and 2012 models.

The changes come courtesy of a slightly altered chemistry in the lithium-ion cells provided by LG Chem.

The revised cells have a slightly different composition of materials in their manganese-spinel chemistry, though neither company provided specific details of the changes. GM compared the changes to adjusting the proportions of sugar and vanilla for better flavor while baking a cake.

With more energy capable of being drawn from the battery, recharging time for a fully depleted 2013 Volt pack will rise slightly.

2012 Chevrolet Volt

2012 Chevrolet Volt

Chevrolet says it will take 4 hours and 15 minutes using a 240-Volt Level 2 charging system, or 10.5 hours using 110-Volt household current.

The revised cell chemistry, Chevy says, has been tested through the equivalent of 150,000 vehicle miles. Results showed that the battery degrades more slowly and can operate at temperatures as low as -30 degrees Celsius (-22 degrees Fahrenheit).

Other changes to the 2013 Chevrolet Volt include a "Hold Drive" button that allows owners to conserve battery-pack energy for use at a particular time or when it will make the car most efficient. This is essentially the "charge-sustaining button" in the Opel/Vauxhall Ampera sold in Europe.

Chevy will also fit the low-emission package standard on later 2012 Volts sold in California to those 2013 Volts sold in New York state as well, making them eligible for High-Occupancy Vehicle (HOV) lane access with only a single occupant.

Visually, the liftgate and roof are now body-colored rather than black. A new interior color--Pebble Beige--is available in both cloth upholstery and leather seats with suede inserts.

And a removable rear-seat center armrest is included in the Premium trim package.

Other changes to the audio system, the Comfort package, and a pair of available Safety packages for the 2013 Volt had been known since mid-April.

But the revisions to the battery pack had not been disclosed before today.

As a range-extended electric car, the Volt travels 25 to 45 miles on grid energy used to recharge its battery pack by plugging in the car. GM notes that roughly three-quarters of all U.S. vehicles travel less than 40 miles a day.

After the battery pack is depleted, the Volt's 1.4-liter gasoline range extender switches on--not to power the wheels but to turn a generator that provides electricity to the 111-kW (149-hp) electric motor that actually turns the drive wheels.

The 2013 Chevrolet Volt will have a total range on grid power plus gasoline of 380 miles.

Production of the 2013 Chevy Volt will start early next month at the Detroit-Hamtramck assembly plant, and 2013 Volts will arrive at Chevrolet dealers starting in August.

Thus far, GM says, owners of existing 2011 and 2012 Chevrolet Volt models have traveled more than 65 million miles in their cars--roughly two-thirds of those miles on electricity drawn from the power grid.


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