Toyota Motor Corp. unveiled an upgraded fuel-cell vehicle that successfully completed a test run Friday, proving its ability to run a longer distance than its existing model, a move to take a lead in the future power-train technology race.

The latest model has accomplished a total distance of 770 kilometres with a single fill-up, more than double the mileage achieved by Toyota's existing model, the company said in a statement.

Toyota has been in a race with global automakers, including General Motors Corp., to develop non-gas-emission vehicles. A major challenge in developing fuel-cell vehicles is their limited driving distance .

Toyota, which became one of the first car makers to obtain government approval in Japan to market fuel-cell vehicles in 2002, said the advanced vehicle is 25 per cent more fuel-efficient than the existing model. It reduces use of electricity for electronic equipment installed in the vehicle, the company said.

In a public road test Friday, two advanced fuel-cell vehicles ran about 560 kilometres from Osaka to Tokyo without refuelling, while keeping their air conditioning on, Toyota said. About 30 per cent of the fuel was unused when they arrived in Tokyo.

Fuel-cell cars are widely viewed as the most promising pollution-free vehicles for the future because they are powered by electricity generated through the chemical reaction between hydrogen and oxygen and emit only water as a byproduct.

Toyota said the company plans to continue its research and development to further improve driving distance, usability at low temperature, durability and cost reduction.