DETROIT — The Toyota Motor Corporation announced that it would build its first plug-in hybrid by 2010, according to the New York Times.

The move puts Toyota in direct competition with General Motors, which has announced plans to sell its own plug-in hybrid vehicle, the Chevrolet Volt, sometime around 2010. Katsuaki Watanabe, the president of Toyota, announced the company’s plans at the Detroit auto show as part of a series of environmental steps.

Toyota, best known for its Prius hybrid car, would develop a fleet of plug-in hybrids that run on lithium-ion batteries, instead of the nickel-metal hydride batteries that power the Prius and other Toyota models, according to Watanabe.

Plug-in hybrids differ from the current hybrid vehicles in that they can be recharged externally, from an ordinary power outlet. In a conventional hybrid the battery is recharged from power generated by its wheels.

Watanabe said the lithium-ion fleet would be made available first to Toyota’s commercial customers around the world, like government agencies and corporations, including some in the United States. He did not say when they would be available to consumers, according to the New York Times.

The Volt also is set to run on lithium-ion batteries, which are more expensive than the batteries currently used by Toyota, but which can potentially power the vehicle for a longer time.

Additionally, Toyota said it planned to develop a new hybrid-electric car specifically for its Lexus division as well as another new hybrid for the Toyota brand. It said it would unveil both at the 2009 Detroit show.

Some environmental groups have pushed for plug-in hybrids, called PHEVs, or plug-in hybrid electric vehicles, as a way to save on gasoline, thus curbing emissions. But some experts say plug-ins may not be the ultimate answer to cutting pollution, if the electricity used to charge them comes from coal-fired power plants, according to the New York Times.