Advanced Onboard Fuel Processor for PEM Fuel Cell Vehicles 2006-01-0216

To reduce greenhouse gas emissions such as CO₂, automakers are actively pursuing alternative propulsion systems. Improvements to current engine technology are being investigated along with new power plant technologies. Fuel Cell Vehicles offer an exciting option by producing electric power through a reaction that combines hydrogen and oxygen to make water. However, hydrogen storage onboard vehicles and construction of an expensive hydrogen distribution and fueling infrastructure remain as challenges today. In addition, greenhouse gas emissions from the production of hydrogen must be considered since most hydrogen is currently produced from non-renewable sources. While these issues are being worked on, Renault has chosen to pursue a fuel cell vehicle with a fuel processor that converts gasoline and other liquid fuels to hydrogen onboard the vehicle.

As presented at the 2005 SAE World Congress¹, Renault and Nuvera Fuel Cells previously developed fuel processor technology that achieved automotive size (76 liter fuel processor with a vision for a 150 liter system) and power (1.3 g/s or 156 kWth of hydrogen production) and reduced the startup time from more than 75 minutes to about 6 minutes to have CO of <100 ppm.

This work is continuing and has already shown further improvements in startup time, controls, and system design. Renault and Nuvera are currently pursuing this fuel processor technology in a multi-year program with the goal of achieving the technical requirements for a commercial vehicle system. This paper presents an overview of the gasoline fuel cell power plant along with recent advances and test results of the fuel processor and the custom control system. Progress since the 2005 paper includes faster startup to 100 ppm CO (under 4 minutes from 25 C and 1.5 min from 40 C), higher power (1.4 g/s of hydrogen), and a working test system (not a mockup) that has the fuel processor and most controls components packaged in an automotive configuration (150 liters, 23 cm height).