Commercialization of Fuel Cell Bipolar Plate Manufacturing by Electromagnetic Forming

Abstract

The cost of manufacturing bipolar plates is a major component to the overall cost structure of a Proton Exchange Membrane (PEM) fuel cell stack. To achieve the commercialization of PEM fuel cells, a high volume and low cost manufacturing process for the bipolar plate must be developed. American Trim has identified high velocity electromagnetic forming as a suitable technology to manufacture metallic fuel cell bipolar plates, because of its low capital cost, flexible tooling and rapid prototyping capability. Through the support from the State of Ohio Third Frontier Fuel Cell Program, a group of collaborators consisting of American Trim, The Ohio State University and General Motors have developed a commercially viable prototype production process to manufacture metallic fuel cell bipolar plates in which electromagnetic coils and forming dies were integrated. To manufacture fuel cell bipolar plates, a metal sheet is accelerated by electromagnetic force to impact against, and take the shape of, the forming die surface. A novel approach which introduces a compliant layer eliminates the need for expendable driver plates in order to reduce the production cost. This process enables continuous manufacturing of fuel cell bipolar plates in short-time cycles at very low cost, which demonstrates strong potential for commercialization. This paper will introduce the electromagnetic forming process developed to manufacture metallic bipolar plates, and include a discussion of the preliminary results. The benefits of using this high velocity electromagnetic forming process over a traditional stamping press will also be discussed. To commercialize electromagnetic forming, coil life and die wear are being investigated. The results of some preliminary experiments involving coil durability and die wear will also be presented. * The authors would like to thank the State of Ohio Third Frontier Fuel Cell Program for its financial support.