Toyota’s new fuel cell truck is a ton lighter than its predecessor, goes 50 percent farther and was built in less than half the time — encouraging signs of progress and commitment as Toyota prepares to launch the second-generation prototype.
Trucks.com got a first look at the new Class 8 truck during a visit to the U.S. technical center of global engineering specialist Ricardo on the outskirts of Detroit.
The Toyota-powered Kenworth truck was publicly unveiled Monday at the Center for Automotive Research management briefing seminar in Traverse City, Mich.
As with its first fuel cell truck prototype, Toyota built the new truck by starting with a commercially available tractor. The automaker hired Ricardo to do the powertrain integration and parts fabrication necessary to convert it from diesel to hydrogen fuel cell power.
The Beta semi-tractor
The new truck, which Toyota calls the Beta model, has 300 miles of range, substantially increasing its utility.
That range comes from increased fuel capacity, up 50 percent to 60 kilograms of hydrogen gas from the first prototype.
Ricardo finished Beta in just six weeks, using a new Kenworth, the T680 low-roof 40-inch sleeper cab model.
The new tractor provided more room for fitting the fuel cell system components, including the substantially enlarged fuel storage system with six 10 kilogram tanks instead of four.
Ricardo’s team fabricated a custom cabinet that holds the fuel tanks and a 12-kilowatt-hour battery pack. The tanks carry the hydrogen, compressed to 10,000 pounds per square inch, that the fuel cell system converts to electricity to drive the truck’s twin electric motors.
The cab is painted a deep, dark red, differentiating it from the original fuel cell tractor’s all-blue color scheme.
Despite its larger size and increased fuel load, the Beta is almost a ton lighter than its predecessor.
Toyota is keeping the finished product’s total weight confidential for now. But the diesel T680 40-inch sleeper model weighs just under 14,000 pounds. It’s heavier with a fuel cell system, Chris Rovik, Toyota’s executive program manager for advanced fuel cell development, told Trucks.com.
“The aim, and we think it is attainable, is to reach weight parity with the diesel” if Toyota commits to additional prototypes and further refinements, he said.
“We also would work on solutions for things like electric brakes, cabin cooling and power steering” that wouldn’t sap valuable electrical power and reduce the truck’s range, Rovik said.
Most of the weight savings come from the compact design and lightweight materials used for the new fuel tank and battery racks and the cabinet that hides them. Engineers also re-designed the high-voltage wiring harness, eliminating more than 100 pounds of copper wire.
Ricardo’s engineers looked at several tractors for the Beta project, but they chose the T680 “because it provided the best ergonomics and functionality,” Colin Kimber, Ricardo’s chief engineer on the project, told Trucks.com.
The extended chassis is roomy enough to easily house the various fuel cell system components and still provide a more spacious cabin.
The new cab “is more production-like,” with improved visibility and a more ergonomic instrument layout, Kimber said. The instrument panel is fairly stock, with the exception of a few gauges, such as hydrogen pressure and range, unique to a fuel cell powertrain.
Nod to ‘the Future’
A notable touch is the gear selector for the single-speed transmission. It’s straight from the Mirai fuel cell sedan that Toyota introduced in 2015. Mirai translates as “the future.”
The Beta truck also has an improved data capture and analytics system.
The first truck used a laptop wired into the system’s brain — the power control unit — to collect data, which then had to be manually uploaded to computers at Toyota’s various research centers. The second-generation truck’s brain can wirelessly send data to the centers.
Beta’s twin fuel cell stacks also are from the Mirai parts bin. But Toyota ditched the first truck’s Mirai radiators in favor of a larger, more efficient standard diesel truck radiator.
There’s no engine to cool, but fuel cell stacks generate a lot of heat. The radiator helps cool them.
Toyota’s system places the fuel cell stacks under the floor of the truck’s cab. The power electronics, cooling system and air compressor for the fuel cell stacks occupy the former engine bay.
It uses the same motors, batteries and fuel cell stacks as the first truck, but the Beta truck’s lighter weight and improved cooling system increase overall performance by about 10 percent, said Andrew Lund, Toyota’s chief engineer for the project.
Including energy stored in the truck’s lithium batteries, the system can produce at least 500 kilowatts of power in short bursts. That’s enough electricity to power almost 130 average American homes.
Twin electric motors in the truck churn out more than 670 horsepower and 1,327 pound-feet of torque — roughly equivalent to the output of the Cummins X15 Efficiency Series diesel engine. As with other electric vehicles, all of that torque is instantly available, giving Toyota’s fuel cell truck impressive acceleration.
Like any other electric-drive vehicle on the road, and unlike diesels, fuel cell vehicles run in near silence and don’t produce harmful tailpipe emissions. When their hydrogen fuel is produced using renewable energy — solar, wind or hydro — the carbon footprint is nearly zero.
With the second-generation truck, Toyota and Ricardo further refined what may someday be a modular fuel cell system kit that is easy to ship and to install, Rovik told Trucks.com.
Whether those kits will hit the market is a decision that hasn’t been made. At the engineering level, though, things continue moving ahead as if more fuel cell trucks are on tap.
The engineering teams already have figured out an additional 500 pounds of weight savings that can be applied in future refinements of the system, Rovik said.