Thanks to its hybrid knowledge, Toyota created the first fuel cell production car. It is a vehicle driven by an electric motor powered by the electricity generated by the chemical reaction between on-board hydrogen and airborne oxygen. Compared to the Prius, the new Toyota Fuel Cell Sedan has replaced its combustion engine by a fuel cell stack and its fuel tank by a hydrogen tank. Two high-pressure tanks actually, that store the hydrogen at a pressure up to 700 bar and that can be filled up in about 3 minutes. The only emission is water.
Built on the hybrid architecture, the Toyota Fuel Cell Sedan features a battery, a boost converter, an electric motor and a power control unit for the handling of the 4 different phases of working.
At very low load driving, meaning at very low speeds or in traffic jams, it is the battery only that provides the energy to drive the car.
At low load driving, meaning at low speeds like in city centres, the fuel cell stack provides enough energy for feeding the electric motor and simultaneously charging the battery.
At high load driving, when a lot of power is required, the fuel cell stack and the battery work together in order to boost the acceleration.
And then, as for a hybrid car, energy is recovered during braking and used for recharging the battery.
The fuel cell stack is composed by hundreds of cells. In each cell it works as follows:
1. Hydrogen is supplied to the anode side.
2. Hydrogen molecules activated by the anode catalyst release electrons.
3. The electrons released from hydrogen travel from the anode to the cathode, creating an electrical current.
4. Hydrogen molecules that released electrons become hydrogen ions and move through the membrane
5. Hydrogen ions bond with oxygen and electrons on the cathode catalyst to form water.
By generating its own electricity from hydrogen, the fuel cell car can help make a future hydrogen based society a reality, and contributes to energy diversification.
Have a look at our Fuel cell video on YouTube!