Weichai Unveils Heavy-Duty Commercial In-Cylinder Direct Injection Hydrogen Engines

The real-world demonstration operation of hydrogen internal combustion engines, led by CATARC Automotive Inspection Center (Tianjin) Co., Ltd., was officially launched in Tianjin. At the event, Weichai debuted its 13L and 8L hydrogen internal combustion engines, with the 8L model standing out as the first-ever heavy-duty commercial in-cylinder direct injection hydrogen engine showcased in China. This milestone marks another significant step for Weichai in clean energy utilization and environmentally friendly power technologies.

Hydrogen, as an efficient and zero-carbon alternative energy source, holds immense potential for reducing greenhouse gas emissions. Hydrogen internal combustion engines (ICEs) meet emission reduction requirements while maintaining costs comparable to traditional ICEs, offering a less complex and more controllable cost solution. They are an effective pathway for achieving energy conservation and emissions reduction in the transportation sector.

Weichai’s 13L hydrogen ICE is a port-injection engine that achieved its first ignition in September 2021. In June 2022, Sinotruk and Weichai jointly launched China’s first commercial hydrogen-powered heavy-duty truck equipped with this engine, delivering 290 kW of power and 2000 N·m of maximum torque. By optimizing injection parameters, valve timing, and ignition timing, the engine effectively resolves backfire issues. It features high-efficiency turbocharging and lean-burn combustion technology to ensure stable and efficient operation and integrates Weichai’s proprietary ECU system for smart and customizable control.

The 8L hydrogen internal combustion engine showcased by Weichai is making its domestic debut.

It features an in-cylinder low-pressure direct hydrogen injection system combined with low-energy spark ignition and precise management of cylinder temperature and flow fields, effectively minimizing the risk of pre-ignition.

With advanced in-cylinder direct injection control technology, it ensures flexible and precise hydrogen fuel delivery, meeting the demands of various engine operating conditions.

High-efficiency, low-inertia turbocharging and ultra-lean combustion technologies enable clean and stable in-cylinder combustion. Together with a simple SCR system, it meets China VI emission standards.

The engine also incorporates a closed forced-circulation ventilation system paired with multiple intelligent sensors, forming a dedicated safety management system for hydrogen ICEs. This system ensures reliable monitoring of hydrogen concentrations in combustion, exhaust, and the crankcase.

Powered by these innovative technologies, the Weichai 8L hydrogen ICE achieves a power output of 257 kW and a maximum torque of 1400 N·m. It is already installed on the Shaanxi Heavy Duty Truck M6000 cargo truck.

At the Hannover Motor Show in September, Weichai introduced its next-generation 15L in-cylinder direct injection hydrogen ICE, paired with Sinotruk's new-generation Yellow River heavy-duty truck. This engine delivers 560 horsepower and 2600 N·m of torque, supports multiple fuels such as methanol and natural gas, and achieves over 90% component compatibility across fuel types.

These hydrogen ICE products highlight Weichai’s leading-edge capabilities in high-efficiency energy conversion, low-emission technologies, broad application prospects, and proprietary innovation. They represent a major breakthrough for China’s domestic power solutions in the field of new energy technologies and contribute "Chinese ingenuity" to the achievement of global sustainable development goals.