Alkaline Battery for Electric Cars
Edison believed cars would be powered by electricity, and in 1899 he began to develop an alkaline storage battery that would power them. He was on to something: In 1900, about 28 percent of the more than 4,000 cars produced in America did run on electricity [source: PBS]. His goal was to create a battery that would run for 100 miles (161 kilometers) without recharging. Edison gave up the project after about 10 years because the ready abundance of gasoline made the electric car a moot point.
But Edison's work wasn't in vain -- storage batteries became his most profitable invention and were used in miners' headlamps, railroad signals and marine buoys. His friend Henry Ford also used Edison's batteries in his Model Ts.