Aside from a couple aftermarket companies that offer conversion kits
to boost a production-model hybrid's battery capacity and allow it to
recharge those batteries from a conventional, 120-volt household
outlet when parked, there hasn't been much action when it comes to
plug-in hybrids. But these kits are expensive and void the factory
warranty. http://www.zone-car.com/?chevrolet-volt-concept.php
Chevrolet Volt Concept - Car News 
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