The car's flat, floorpan-mounted battery pack (85 kWh) accounts for about 30% of the significant total vehicle weight, 4, 642 pounds.

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With space-frames, car makers can clip extruded tubes or sections made of steel or aluminium on to a basic floorpan.

ECONOMIST: Cars

But beyond that, he is planning to build all Nissans and Renaults on the same ten or so platforms, sharing the basic floorpan that is the core of a car body and using a common range of engines, gearboxes and other parts.

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