Fuel Cell operating on Conventional Fuels as AUxiliary Power Unit for Electrical Vehicles

Purpose and goal

The aim of the project was to develop a demonstrator model of an auxiliary power unit to be used in electric vehicles based on HT-PEM fuel cells. In order to reach the specified weight and volume targets a large part of the project was focused on development of metallic bipolar plates (BPP) to replace conventional graphite based plates. Chalmers´ task was to develop new test methods, investigate degradation processes and give advice with regards to material choice and coating development. Impact Coatings (IC) were responsible for developing protective/conductive coatings.

Expected results and effects

Several new test methods for degradation of metallic BPPs were developed at Chalmers; from simplified tests to long term tests in a HT-PEM fuel cell which led to new insights about degradation mechanisms. This knowledge will be valuable when deciding on operation parameters material choices for HT-PEM fuel cells. Furthermore, IC developed a Ceramic Max Phase coating which reduced corrosion and increased electric conductance and they were also able to reduce the production cost per plate by more than 50 %. A manuscript for publication in Fuel Cells has been submitted.

Planned approach and implementation

Since no standardized test method existed when the project was commenced much effort was focused on the development of tests which simulate a fuel cell environment in which material degradation could be studied. The relevance of this test was referenced against material tests in a fuel cell, with good agreement. Additionally, a new corrosion cell was designed which enabled mechanistic studies of corrosion. Detailed electron microscopy was used for analyzing materials and coatings. IC optimized both their coating composition and process towards HT-PEM application.