The NiMH battery pack used for the Prius
The NiMH battery pack used for the Prius
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Toyota Motor Corp developed a system for reusing nickel-metal hydride (NiMH) rechargeable batteries used for hybrid electric vehicles (HEVs) as stationary batteries for residences, etc and started a field test of the system.

The company made this announcement Feb 17, 2012. With the new system, it might become possible to supply stationary rechargeable batteries, which are recently drawing attention, at low cost.

The capacities of rechargeable batteries decrease after they are used for HEVs. Therefore, to ensure a battery capacity required for a stationary battery, it is necessary to use many automotive batteries, increasing volume and mass. However, residential batteries can be larger and heavier than automotive batteries, and, thus, used automotive batteries can be sold as stationary batteries, Toyota said.

So far, Toyota has been disassembling NiMH batteries that can no longer be used for HEVs, applying reduction treatment, etc to them and reusing them as batteries for HEVs. The company plans to use such batteries as stationary batteries first and, then, recycle them as batteries for HEVs.

Nissan Motor Co Ltd and Mitsubishi Motors Corp have already started field tests of reusing automotive batteries as stationary batteries. But they are recycling lithium-ion (Li-ion) rechargeable batteries used for electric vehicles.