Wheego has moved the battery pack forward, putting more weight on the front wheels.

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Alta's technology can reduce that battery weight by 70 percent, saving approximately 25 pounds of pack weight.

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The weight of the battery pack of some of the early Tesla Roadsters came to 1, 000 pounds.

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The system allows a 1.6kWh lithium-ion battery pack, mounted behind the seats for weight distribution reasons, to be charged through a rear axle electro-hydraulic brake energy regeneration system.

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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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