Without going into details, suffice it to say that a hotter battery means shorter cycle and calendar life.

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Nanophosphate EXT is based on A123's proprietary lithium iron phosphate battery technology, which offers high power, long cycle life, increased usable energy and excellent safety as compared to other available battery technologies.

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Unlike lead acid or other advanced battery technologies, Nanophosphate EXT is designed to maintain long cycle life at extreme high temperatures and deliver high power at extreme low temperatures.

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