Its battery, the size of a tatami mat and weighing about 400 pounds, is under the floor, which helps give the car a lower center of gravity.

它的电池，大小如榻榻米，重400磅，位于汽车的底部，使车子的重心较低。

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The design and manufacture for the gravity-casting molds of lead-acid starter battery grids, also the processing technique of casting are explained.

论述了起动用铅酸蓄电池重力铸造板栅模具的设计、制造和铸造工艺技术。

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In other green tech and design news, Hitachi unveiled an impressive new wireless controlled robot to help with the Fukushima Daiichi cleanup and London-based designers Martin Riddiford and Jim Reeves developed the GravityLight, an amazing low-energy, battery-free light that works by harnessing the power of weight and gravity.

ENGADGET: Inhabitat's Week in Green: madder root batteries, sun-powered plane and the world's first fiber-optic solar cell