TOYOTA CHALLENGE IN MAKING THE HYDROGEN CAR–HYDROGEN REACTION THAT CREATES ELECTRICITY TO POWER AND CHARGE BATTERIES RESULTS IN WATER EXHAUST- HOW TO STORE THE HYDROGEN FUEL–INFRASTRUCTURE OF HYDROGEN FUEL GAS STATION–HYDROGEN IS BASICALLY USED FOR ROCKET FUEL

 

1. They say the largest problem was the water that's emitted instead of exhaust gas.

If the water freezes in cold weather, it may block air intake, causing the car to stop. To sell the car globally, the engineers must ensure it runs stably under all weather conditions.

"The water gave us a lot of trouble. It was said those who get control over water will be the winner in the fuel-cell race."
Mikio Kizaki / Toyota Motor

2. Engineers took carbon fiber used in aircraft and developed it for use in automobiles. They went on to clear many other challenges, including reducing costs.

3. Hydrogen has been used worldwide as rocket fuel and for other purposes. In fact Japan produces a large quantity of it.

The Tokyo Metropolitan Government supports the move toward hydrogen. It is building hydrogen stations ahead of hosting the 2020 Olympics. Expectations are growing that fuel-cell cars will follow hybrids and electric vehicles in opening up the era of eco-friendly vehicles.

http://www3.nhk.or.jp/nhkworld/english/news/techtrends/20141127.html