Curtis A Richardson

US Patent:

20030235723, Dec 25, 2003

Filed:

Mar 13, 2003

Appl. No.:

10/388129

Inventors:

Haskell Simpkins - Grand Blanc MI, US
Karl Haltiner - Fairport NY, US
Curtis Richardson - Voorheesville NY, US

International Classification:

H01M008/02

US Classification:

429/013000, 429/012000, 429/030000, 267/064110

Abstract:

A passive gas spring disposed within a fuel cell assembly adjacent a fuel cell stack for maintaining the stack under compression at elevated temperatures. The spring includes at least one membrane formed of a metal alloy stable at the operating temperatures required of the fuel cell assembly. The membrane closes a chamber for retaining an amount of gas. As temperature of the assembly changes, differential thermal expansion of fuel cell components and supporting structural elements can cause height mismatches between the stack and the supporting structure, otherwise resulting in a loss of compression in the assembly. Because the temperature of the gas also increases, however, the spring force of the gas spring increases, thereby maintaining compressive load on the various assembly seals. A mechanical spring may also be provided.