1905
An American engineer named H. Piper filed a patent for a petrol-electric hybrid vehicle. His idea was to use an electric motor to assist an internal-combustion engine, enabling it to achieve 25 mph.
1966
U.S. Congress introduced first bills recommending use of electric vehicles as a means of reducing air pollution.
1974
As part of the Federal Clean Car Incentive Program, engineers Victor Wouk and Charlie Rosen created a prototype hybrid gas-electric vehicle using a Buick Skylark body. The U.S. Environmental Protection Agency tested the vehicle, certified that it met the strict guidelines for an EPA clean-air auto program — and rejected it out of hand.
1976
U.S. Congress enacted Public Law 94-413, the Electric and Hybrid Vehicle Research, Development, and Demonstration Act of 1976. Among the law’s objectives were to work with industry to improve batteries, motors, controllers, and other hybrid-electric components.
http://www.hybridcars.com/history/history-of-hybrid-vehicles.html1991
The United States Advanced Battery Consortium (USABC), a Department of Energy program, launched a major program to produce a “super” battery to get viable electric vehicles on the road as soon as possible. The USABC would go on to invest more than $90 million in the nickel hydride (NiMH) battery. The NiMH battery can accept three times as many charge cycles as lead-acid, and can work better in cold weather.