Two weeks ago, Chevrolet unveiled its 2013 Spark minicar and confirmed that it would offer a Spark EV all-electric model--a story GreenCarReports broke the night before.

But within a few days, an intriguing question came up: Where does GM plan to build its first new all-electric car since the late lamented EV1?

The sole global assembly plant for gasoline and diesel models of the 2013 Chevrolet Spark is in Changwon, South Korea. But a spokesman for GM Korea told WardsAuto that the company had no prototype Spark EV on site, and that the final assembly site had not been decided.

We think there's a simple answer to the question: GM will import rolling Spark vehicles without powertrains (known as "gliders") from Korea to the U.S., and add battery packs, electric motors, and power electronics at an assembly site somewhere in the country.

This is the same process used by Azure Dynamics to electrify the Ford Transit Connect small commercial van, turning it into the Transit Connect Electric model now on sale in small numbers to fleet buyers.

Toyota, on the other hand, plans to build its 2012 RAV4 EV at its RAV4 plant in Woodstock, Ontario. Battery packs and other running gear will be supplied by Tesla Motors from its own California facilities.

2013 Chevrolet Spark EV cutaway

2013 Chevrolet Spark EV cutaway

But U.S. assembly makes sense for the Chevrolet Spark EV because its lithium-ion battery cells are being supplied by A123 Systems, which is now in pilot production at its new cell plant in Holland Livonia, Michigan.

GM said in September it would award A123 a cell supply contract for an electric vehicle, but it didn't say then which one it was for. We know now it is the Spark EV.

Not only are the lithium-ion cells one of the most costly components of a battery electric vehicle, but they are considered hazardous cargo--so shipping them internationally is both slow and cumbersome.

Moreover, General Motors tomorrow will announce more information about its plans to produce electric motors for future electrified products. It already designs electric motors in Wixom, Michigan, and builds them for certain vehicles--though not all--in a plant in White Marsh, Maryland.

2013 Chevrolet Spark minicar

2013 Chevrolet Spark minicar

Adding those pieces together, we expect A123 to manufacture the cells for the Spark EV's battery pack in Michigan, and GM to build them into battery packs and put those packs into Sparks somewhere in the U.S.

Final assembly site? We haven't a clue, at least not yet. But we'd expect it to be in Michigan or a nearby state.

And for volumes of only 2,000 a year--enough to meet California's Zero Emission Vehicle sales mandate--you hardly need a new plant. A single line in an existing facility might do.

We rather wonder if it might happen in the Detroit-Hamtramck plant that now builds the 2012 Chevrolet Volt range-extended electric car, which currently builds just a fraction of its total capacity.

2011 Chevrolet Volt Production Line

2011 Chevrolet Volt Production Line

Regardless of where in the U.S. the pieces come together, we suspect GM will be able to deem the car "U.S. built," unlike the standard Chevrolet Spark--which will remain an import.

That's because "U.S. built" has to do with the final assembly site, leading both the Tesla Roadster (with gliders built in England) and the upcoming 2012 Coda Sedan (with gliders built in China) to get the domestic seal of approval because their running gear--batteries, motors, and other components--are installed on U.S. soil.


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