FUEL CELL STACK COMPRESSION SYSTEM

摘要

A fuel cell stack compression system in which a spring assembly and mechanical linkage assembly are used in conjunction with tie rods and tie bars to apply a compressive load to a fuel cell stack. The linkage assembly includes a lever and three pins to redirect the force or movement generated by the spring assembly into a movement or force for the tie rods. The tie rods, in turn, connect to the tie bars which span the top end plate of the fuel cell stack and transfer the load to the stack. The linkage also includes a slotted bearing which compensates for the circular arc formed by the lever and allows the spring assembly to be rigidly mounted under the bottom end plate. The spring assembly comprises multiple springs arranged in parallel and designed to provide a non-linearly decreasing load as the stack compresses due to cell consolidation. This load profile reduces overall stack shrinkage while providing high pressure at the beginning of life to insure proper cell-to-cell contact.