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A new Toyota fuel-cell hybrid can travel more than double the distance of an earlier prototype, increasing cruising range from 330km to 830km, the carmaker says.
The limited cruising range of previous fuel-cell systems hampered their widespread use but the improved Toyota FCHV-adv (fuel-cell hybrid vehicle-advanced) system boosts the chances of such a vehicle going into production.
The carmaker said fuel efficiency was improved by 25 per cent through improving the fuel-cell's performance, enhancing the regenerative brake system and reducing energy consumed by the auxiliary system.
Nickel-metal hydride batteries, similar to those in the Prius hybrid, are used in the prototype.
More changes included making the fuel-cell more durable. The improved cell feeding from Toyota's own high-pressure hydrogen tanks made the 830km distance possible, more than doubling the range of the previous prototype, the Toyota FCHV.
The Toyota FCHV-adv also deals with the low-temperature start problems typically associated with fuel-cell vehicles.
The building block of the Toyota FC Stack is the Membrane Electrode Assembly (MEA), where engineers focused on the basic problem of internally produced water interfering with electrical generation within the MEA at low temperatures.
Toyota first had to understand the behaviour and amount of water generated in the fuel-cell to allow its engineers to optimise the MEA design to improve low-temperature start-up.
As a result, the Toyota FCHV-adv can start and operate in cold regions at temperatures as low as -30C, meaning the vehicle can be used in a wider variety of conditions and climates.
Toyota said that while it was doing research and development, it was working with government, energy companies and other parties to bring about widespread fuel-cell vehicle use.
The FCHV-adv is based on an all-wheel-drive Toyota Highlander. All up, the vehicle weighs 1880kg. The hybrid fuel-cell develops 90kW and 260Nm of torque. Hydrogen tank capacity is 156 litres.
