The Economist has published an excellent article on the history of automotive battery technology. It notes that electric cars were common in the first decade of the 20th century until the invention of the electric starter in 1912 made internal combustion engines, which provided better range and power, the dominant technology.
In August 2005, the USPTO established a new cross-reference class for hybrid electric vehicles (Class 903). There are now some 1,579 patents and 1,127 published applications classified under Class 903. Cross-reference classes are intended to provide supplemental information and are never assigned as primary classifications.
A number of famous inventors tried their hand at perfecting electric automobiles. One of the earliest patents (No. 594,805) for an electric car was issued in 1897 to Hiram Maxim, inventor of the Maxim machine-gun. Thomas Edison also attempted to develop (with limited success) improved batteries for the automotive industry.