2016 Toyota Mirai |
The system provides better energy efficiency than internal combustion engines, superior environmental performance with no emissions of CO2 or pollutants when driving, and the same level of convenience and autonomy as gasoline engine vehicles, and a hydrogen refuelling time of about three minutes.
The system uses Toyota-developed components including the Toyota FC Stack, FC boost converter, and high-pressure hydrogen tanks.
2016 Toyota Mirai |
The new Toyota FC Stack achieves a maximum output of 114 kW (155 DIN hp). Electricity generation efficiency has been enhanced through the use of 3D fine mesh flow channels (a world first), which ensure uniform generation of electricity on cell surfaces, providing compact size and a high level of performance, and a world-leading power output density of 3.1 kW/L (2.2 times higher than that of the previous Toyota FCHV-adv limited-lease model).
The amount of water on fuel cell electrolyte membranes has a substantial influence on electricity generation efficiency. Control of the amount of water is carried out using an internal circulation system for circulating the water created when generating electricity, meaning the Toyota FC Stack is a world-leading system that, unlike systems used in all other previous Toyota fuel cell vehicles, does not require the use of a humidifier.
FC Boost Converter
A new compact, high-efficiency, high-capacity converter has been developed to boost power generated in the Toyota FC Stack to 650 volts. Increasing the voltage has made it possible to reduce the size of the electric motor and the number of Toyota FC Stack fuel cells, leading to a smaller, higher-performance Toyota Fuel Cell System, thereby reducing system costs.
High-pressure Hydrogen Tanks
Tanks with a three-layer structure made of carbon fiber-reinforced plastic and other materials are used to store hydrogen at a very high pressure of 70 MPa (70 megapascals, or approximately 700 bar). Compared to the high pressure hydrogen tanks used in the Toyota FCHV-adv model, tank storage has been increased by approximately 20 percent while both weight and size have been reduced to achieve a world-leading5 5.7 wt%.