Electric Cars

Fuel Cells Take Us Back…To The Future

May 24, 2022

Bringing NASA Technology to Your Car

Hydrogen fuel cells may sound like a new thing – the first mass-production fuel cell car for America, the Toyota Mirai, will be delivered in late 2022 – but they’re actually technology that pre-dates the automobile.

In 1838, a Welsh physicist combined hydrogen and oxygen in the presence of an electrolyte to produce an electric current – though the amount of current generated wasn’t enough to power a vehicle. But, by the 1960s, fuel cell technology was being used in America’s Gemini and Apollo spacecraft, where it provided crews with electricity and water, which were generated by stored hydrogen and oxygen.

Hydrogen is the most abundant element on earth by quantity, though not by weight. The lightest element in the universe can be produced from a number of domestic resources. The goal of the U.S. Hydrogen Council, of which Toyota is a founding member, is promoting the widespread use of decarbonized hydrogen for transportation by 2030.

Why hydrogen? It can be produced from bio-resources or renewable electricity via electrolysis, so production can be clean and environmentally friendly. Plus, refueling a hydrogen-powered vehicle can be accomplished in a similar amount of time to refueling a gas vehicle – one of the current stumbling blocks of battery-powered electric car.

An Electric Vehicle, Without a Plug?

Let’s make this clear up front: a hydrogen fuel-cell vehicle is an electric vehicle, it’s just an electric vehicle without a plug. There’s no big battery to recharge – you simply fill a tank with hydrogen, which takes about five minutes.

Fuel cells had been studied for the automotive sector in the past – but the technology only recently became practical and cost-effective. Toyota began its fuel cell development around the same time as its original Prius nearly 25 years ago, and the Mirai incorporates a lot of technology from the company’s hybrid program.

With an FCEV (fuel cell electric vehicle) like the Mirai, the fuel is non-toxic, compressed hydrogen gas rather than liquid gasoline. The gas is held under pressure, and then fed to a fuel cell system, which combines the stored hydrogen with oxygen from the air. A chemical reaction produces electric current – and water, which drops out of a vent pipe underneath the car.

Fuel cells are a scalable technology – they can be made small enough to power a phone, or large enough to power a building, or anything in between. Toyota, whose Mirai is the only mass-produced fuel cell vehicle available in America, also uses fuel cells to power a fleet of class-8 semi trucks that are rated for an 80,000-pound load, and that are used to move freight in and around the port of Long Beach in California.

Toyota’s New Mirai

The $49,500 Mirai – Japanese for “future” – will be arriving in dealership showrooms in December 2022. It is built on the company’s high-strength GA-L platform, shared with some Lexus luxury cars, with sophisticated multilink suspension, superb handling agility and an exceptionally smooth, quiet ride.

Toyota developed the solid-polymer electrolyte fuel cells used in the first- and second-generation Mirai models in-house. To help foster FCEV proliferation, the company has released over 5,000 of its patents, royalty-free.

Mirai has an electric “supercharger” for its fuel cell – aan electric air compressor pressurizes the intake air, and a water-cooled intercooler reduces the temperature of the compressed air before it enters the fuel cell stack. A water-cooled oil cooler integrated with the air compressor helps maximize efficiency.

The air intake system is designed to mitigate noise, which is virtually unnoticeable to occupants. By necessity, the intake air for the fuel cell must be purified. And so, an electrostatic air cleaner element captures ultra-fine particles, and a charcoal filter removes chemical substances.

Electricity generated by the Mirai’s fuel cell and the regenerative braking system is stored in a lithium-ion battery. Pressing the accelerator pedal yields immediate flow of electric power from the fuel cell and/or battery to the rear-mounted AC synchronous electric motor, which drives the rear wheels. The advantage of a fuel cell drivetrain compared to a battery-electric drivetrain is that the battery can be much smaller, which means the vehicle can overall be much lighter and more efficient.

What About Hydrogen Infrastructure?

As it did with the first-generation Mirai, Toyota will include up to $15,000 of complimentary hydrogen with a purchase or lease. The problem for the earliest adopters of fuel cell driving may be finding where to fill up. As of early 2022, fewer than 50 publicly-accessible hydrogen filling stations exist in America. However, the state of California has almost 40 of those – so if you live in California, and close to a hydrogen station, a Mirai or similar fuel cell vehicle may give you the best of electric driving with the convenience of quick refueling.