DETROIT — Although Toyota is the world leader in producing fuel-efficient hybrid cars, and it has plans to introduce a plug-in hybrid and a battery-powered city car (versions of both were on the stand at the auto show here), the company has been outspoken about the limitations of some green-vehicle technologies. It’s been particularly vocal about the drawbacks of plug-in hybrids.

At the auto show this week, Toyota held a news conference with Koei Saga, managing officer of the Toyota Motor Corporation with responsibility for advanced technology and battery development. Mr. Saga announced that Toyota had set up a research division with 50 engineers to develop advanced lithium-ion batteries for its plug-in hybrids.

But Mr. Saga harbors considerable doubt about the current prospects for long-distance battery-only cars. He said (through a translator) that limited range means that E.V.’s work best as “very small commuter-type vehicles” for use in major metropolitan areas (he used Europe and Japan as examples). Asked if longer-range E.V.’s were possible with current technology, he said that could happen only “if we forget about battery life and if we forget about the cost incurred for replacement of those batteries.”

Cost remains an issue, Mr. Saga said. In 10 years, he said, Toyota would like to reduce the cost of lithium-ion batteries by more than 50 percent. But he pointed out that the price of batteries for cellphones and computers has fallen much faster.

Battery cars capable of extended highway travel are relatively far in the future, Mr. Saga said. He envisioned such electric cars working best if they could obtain electricity not from batteries, but from an interaction with the highway itself. Just such a system has been tested by the Advanced Institute of Science and Technology of Korea, which uses induction strips and inverters embedded in the road to recharge batteries when cars drive over them.

Asked if the world’s vehicles would ever be exclusively electric, Mr. Saga said, “In my personal view, I think we will never abandon the internal-combustion engine.” He did envision a possible future for fuel-cell vehicles and internal-combustion cars that burn hydrogen, however.