Last month, sales of the Chevrolet Volt stayed strong while the Nissan Leaf languished.

This month, it's more of the same.

In July, Chevrolet sold 1,849 Volts, bringing its total for the first seven months of the year to 10,666--and its total U.S. sales since launch to 18,663 (including 7,671 in 2011 and 326 in December 2010).

By contrast, Nissan sold 395 Leaf battery-electric vehicles, giving it a 2012 total thus far of 3,543 (down 26 percent on last year's 4,806 as of July 2011), and overall U.S. sales since launch of 13,236  (9,674 in 2011 and 18 in December 2010).

Nissan has lately resorted to lower-cost lease offers to boost sales of the lagging Leaf. Its vice-president of sales, Al Castignetti, attributes the battery-electric car's low sales this year to a variety of causes, including a change to dealer distribution and increased competition from other plug-in offerings.

In July, Toyota delivered 688 units of the third high-volume plug-in car on the U.S. market, the 2012 Toyota Prius Plug-In Hybrid.

That's just barely fewer than last month's 695, and it brings the number of plug-in Prius hybrids delivered since February to 5,021.

That Toyota total is roughly 40 percent higher than the Leaf total, but comes nowhere near the Volt's more than 10,000 sales--leaving the Volt the clear winner in the plug-in arena this year, after it was outsold by the Leaf last year.

2012 Ford Focus Electric, New York City, April 2012

2012 Ford Focus Electric, New York City, April 2012

While industry watchers were keenly interested to see if Ford could improve on last month's sales of 89 Ford Focus Electrics, the actual total was a mere 38. July was the second month in which Ford's first battery-electric car was delivered in volume.

The final vehicle that contributes to plug-in sales is the Mitsubishi i minicar, of which 33 were delivered, a number identical to the sales the month before, in June.

Coda Automotive, Fisker Automotive, and Tesla Motors refuse to report monthly deliveries of their low-volume electric vehicles.

Overall, the market in the U.S. remains on track to log deliveries that are roughly double those of the 17,000-plus plug-in vehicles sold in 2011.


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