Hydrogen Fueled ICE, Successfully Overcoming Challenges through High Pressure Direct Injection Technologies: 40 Years of Japanese Hydrogen ICE Research and Development 2018-01-1145

After some 40 years of practical research and testing in Japan, the technology for a high pressure direct injection hydrogen internal combustion engine (ICE) with near-zero emissions free from CO2 was successfully developed by the author. Four fundamental challenges to make a hydrogen car a competitive alternative to both electric and traditional fossil fuel vehicles were successfully met. (1) Hydrogen’s lack of lubrication destroys the sealing surface of the injector nozzle. (2) Injectors must be of very small size to be installed onto the engine head where the four valves are located on each cylinder. (3) Multi-injection requires high dynamic response. (4) Liquid hydrogen tank’s internal pump would fail when bringing liquid hydrogen (LH2) to the required high pressure levels due to frictional heat. Technology solutions by this author to these challenges result in a hydrogen internal combustion engine vehicle, delivering high specific power, and brake thermal efficiency of 40% or higher, using direct injection of hydrogen fuel. The hydrogen ICE solution using high pressure LH2 pumps, hydraulically-operated common-rail-type small gaseous hydrogen (GH2) injectors with no leakage of hydrogen gas, and a cryogenic LH2 fuel tank are detailed. Engine test performance and emission data running a 4-cylinder with a total stroke volume of 4.7-liter, 4-stroke and hybrid spark-ignition engine with diesel common-rail type injectors are presented. The advantages of an ICE over fuel cell and electric vehicle are explained. A five year plan for a development-to-production schedule of a vehicle with the high pressure direct injection hydrogen ICE is presented.