Plug-in hybrids are currently the holy grail among alternatives. Similar to regular hybrids, plug-in hybrids also recharge from a regular outlet, theoretically to run the vehicle longer on its electric battery before switching to the gasoline engine.
The challenge to make plug-in hybrids is not just the battery. Besides that well-documented issue, the other major problem continues to be educating the public on how hybrids work. Apparently many continue to believe the electric motor moves the car until the battery powers down. The hybrid then switches to the gasoline engine, which then recharges the battery. Hybrid systems actually continue to recharge the battery which is why they're inefficient in storing quickly the massive charge needed for plug-in hybrids.
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