We checked the 150 MPG Toyota Prius at the Clean Vehicle Technology Expo in Ontario California. There were a lot of pure electric cars and hybrid cars there, some in early concept stages, other (pre)production. But Hymotion's new lithium-ion battery pack for the Toyota Prius really got our attention. While it may not lower gas prices, it does promise to make trips to the gas station a lot less frequent.

The 175-pound battery pack, which is sold as aftermarket kit, converts the car into a plug-in hybrid and allows it to run on electric power for the first forty miles of a trip. It installs in the spare tire well of the trunk, leaving the entire trunk space for cargo, so you can still drive your spare tire in there, and have plenty room left. In average Prius, the gasoline engine still does the majority of the work and the batteries merely take over at low speeds.

Aftermarket kit from Hymotion however changes much. Owners charge up their vehicles with a regular 110 or 220 volt extension cord and afterwards the car will drive dozens of miles solely on electrical power. As you can expect, total gas mileage goes through the roof and company executives claim drivers can easily exceed 150 miles-per-gallon in the city and 100 MPG on the highways.