Hyundai’s Fuel-Cell Dreams Remain Xcient

May 25, 2023

Sebastian Blanco

Hyundai’s fuel-cell truck fleet is growing. The company is about to bring a fleet of hydrogen-powered 6x4 Xcient Fuel Cell Class 8 tractors to the U.S. It displayed one of the large cabs at this year’s ACT Expo in Anaheim, California, alongside even larger ambitions for hydrogen mobility. Hyundai sees this as the key moment when its focus shifts from developing the truck to developing the hydrogen infrastructure and fuel supply.

The H₂ tractor at ACT was the latest step in a multi-year plan to expand the number of Xcients used worldwide, following the establishment of Hyundai’s HTwo brand to promote its 20-plus years of hydrogen research. Heavy-duty trucks – and the partnerships to make them operational – are an increasing part of that project.

In 2021, Hyundai announced it would deliver 30 Xcient semis to the Port of Oakland through the NorCAL Zero project. Before the trucks could get to work, though, Hyundai had to find partners. First Element Fuel set up a refueling infrastructure, for example, and Glovis America is the actual fleet operator. There was plenty of government help, too, according to Mark Freymueller, head of commercial vehicle business innovation at Hyundai Motor Co.

“The whole NorCAL project, with all the support from the government — from [the California Air Resources Board] to Alameda County – that gets us roughly to diesel parity for the operation cost,” he said.

Hyundai can now focus on deploying the trucks after decades of developing fuel-cell technology. According to Martin Zeilinger, head of Hyundai Motor’s commercial vehicle development, a walkthrough of the ACT Expo show floor was an easy way to see how far fuel-cell systems have come in recent years. Hyundai’s second-generation, mass-production fuel-cell vehicle (FCV), the Nexo, was launched in 2018. The Nexo’s fuel-cell system is much better integrated than the first-generation system found in the Tucson FCV launched in 2013. It’s powerful enough that a doubled-up version powers the Xcient.

Compared to the fourth- or fifth-generation production batteries found in EVs, per Zeilinger’s reckoning, or the century-long effort to improve the internal-combustion engine, hydrogen fuel cells are relative infants despite decades of lab work. Fuel-cell technology is now getting out into the real world where lessons are learned and supply chains get built.

“What I’m saying is that it’s a relatively young industry,” he said. “With the volume going up, there will be more integration, there will be more technology, there will be significant cost decreases.”

U.S.-bound Xcients

Hyundai now has some real-world data to better refine how it deploys H₂ trucks in the future. Hyundai currently has between 100 and 150 Xcient trucks that have collectively driven more than 4 million miles in operations with various partners in five countries: Germany, Switzerland, Israel, South Korea and New Zealand. Up next, the U.S.

Hyundai always planned to deliver the trucks in 2023 and said in Anaheim that the first North America-specific Xcients were on track for June. The general cab-over design remains the same between the U.S.-bound Xcients and those used elsewhere. Parts of the powertrain are similar, too, such as the two fuel-cell stacks that work together in one system to power Hyundai’s commercial-vehicle lineup. In the U.S. Xcients, these stacks each produce 90 kW, for a total output of 180 kW. Overseas Xcients use two 95-kW stacks and have 190 kW of total power.

A 72-kWh battery might seem large when there’s an onboard fuel-cell system that can generate electricity as needed. But fuel cells are most efficient when operated in a constant manner, Zeilinger said. If the vehicle were to regulate the stack’s operation by speed, it would create regular transient periods of higher or lower demand. Instead, the battery fills in the gaps both when extra energy is needed to accelerate and when energy from regenerative braking needs somewhere to go.

A DC-AC inverter sends the power through a six-speed transmission (only five gears are used) to a motor that produces a maximum output of 350 kW and 1,650 lb-ft (2,240 Nm). There’s also an electric turbocharger to bring more air into the stack and a humidifier to prevent membranes from drying out.

The fuel-cell stacks, battery, inverter, motor and transmission are the same between the global and U.S. Xcient models. The difference lies in the amount of fuel on board, which is greater for the U.S. trucks given their expected longer distances. Overseas, the Xcients get five tanks at 350-bar (5,076-psi) pressure that collectively hold 32 kilograms of hydrogen. That’s enough for a range of more than 250 miles (400 km) and can be refueled in 15 minutes.

In the U.S., the Xcient gets 10 hydrogen tanks pressurized at 700 bar (10,152 psi), or 68 kg of hydrogen, which Hyundai expects will be good for 450 miles (725 km). Refueling should take 30 minutes. The U.S. Xcient also has two drive axles, compared to one in other countries.

Hyundai’s next target for Xcient trucks in the U.S. is a fleet that will roam the Southeast. While Hyundai would work with partners on the refueling and other efforts, the overall project is more in-house than NorCAL Zero.

Expanding hydrogen fleets

Once all 30 Xcients are in place, NorCAL Zero will have the largest Class 8 hydrogen truck fleet deployment in the U.S. But not for long. Last fall, Hyundai broke ground on what it calls its “Metaplant America,” a new car plant that will be able to build up to 300,000 battery-electric passenger cars a year. At the ACT Expo, Hyundai announced it is readying a fleet of about 50 Xcients to take advantage of a new hydrogen commercial-vehicle value chain as they run between Hyundai and Kia automotive and supplier plants in Georgia and Alabama as well as nearby ports.

“The plant is following [global corporate renewable energy initiative] RE100, and we want to make the inbound and outbound logistics zero-emission, as well,” Freymueller said. “And that’s where the commercial-vehicle part came into play.”

Hyundai could even produce its own hydrogen for the Southeast project, as it will do at its plant near Cheongju, Korea, starting in 2024. There, a fuel-cell-powered garbage truck will collect food waste, which will be turned into biogas and then hydrogen that will be used to refuel the garbage truck and be made available to residents of Cheongju. Or Hyundai could work with partners in Georgia.

“Now the part comes where we need to convince customers, where we need to find partners on the hydrogen supply side and build up these relationships to get vehicles on the road,” Freymueller said. “[Unveiling the vehicle at ACT] was a big day because the truck is not the bottleneck anymore. We have a truck here, and you can buy it.”

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