PEMFC Stack Sealing Using Silicone Elastomers 2003-01-0801
The economic viability of PEM Fuel Cells for transportation uses requires significant reduction in the cost of assembling and sealing the PEM stack. Additionally the stack sealing system or method must last the life of the stack, is often used to enhance the structural strength of the stack and provide performance-enhancing functionality.
This paper discusses PEM fuel cell stack sealing manufacturing and assembly methods. Methods examined include; die-cut gaskets, fabricated press in-place, insert molded designed profile, dispensed and other advanced sealing concepts.
Economic comparison utilizing a value in place analysis takes into consideration seal assembly and stack fabrication methods in addition to seal material and processing costs. This analysis yields a method for rational selection of the best sealing method to be employed for the stack design and production volumes being considered.
Data demonstrating of the success of silicone elastomers in PEM fuel cell stack sealing includes resistance to degradation, inertness to leaching, adhesion and other silicone processing advantages. Standard and accelerated testing of gasket materials is discussed as well as specifications for key life testing of the seal and sealing material with specific relevance to PEM fuel cells.