Device and method for determining the operating parameters of indiviudal cells or short stacks of fuel cells

1. A fuel cell stack which comprises:

a plurality of medium or high-temperature fuel cells aligned in a row and defining opposite ends,

first and second clamping elements respectively positioned near opposite ends of said row of fuel cells,

first and second thermally insulating end elements respectively positioned between said first and second clamping elements and respective opposite ends of the row of fuel cells, said first and second thermally insulating end elements being essentially pressure resistant elements being capable of applying clamping force to the row of the fuel cells via said first and second thermally insulating end elements, and

exterior insulation elements separate from the first and second thermally insulating end elements positioned around sides of said row of fuel cells, said exterior insulation elements embracing outer lateral sides of said first and second thermally insulating end elements but not contacting said first and second clamping elements.

2. The fuel cell stack according to claim 1 , wherein further fuel cell components, such as high-temperature heat exchangers, reformers and/or burners, are contained in a space formed by the exterior insulation and the first and second thermally insulating end elements.

3. The fuel cell stack according to claim 1 , wherein at least one of the first and second thermally insulating end elements includes openings for the passage of inlet and outlet pipes for the process gases involved in the operation of the fuel cells.

4. The fuel cell stack according to claim 1 , including tensioning screws for holding the first and second clamping elements under tension against each other with at least one clamping element being spring-loaded by spring elements located on a side of said at least one clamping element opposite the row of fuel cells.

5. The fuel cell stack according to claim 4 , wherein the first and second clamping elements and the tensioning screws form a mechanical frame which functions as a housing and includes electrical connectors.

6. The fuel cell stack according to claim 1 , wherein the first and second thermally insulating end elements are made of porous ceramic material.

7. The fuel cell stack according to claim 1 , wherein the first and second thermally insulating end elements consist of a metallic grid or supporting structure.

8. The fuel cell stack according to claim 1 , wherein the cells comprise solid oxide fuel cells or molten carbonate fuel cells.

9. The fuel cell stack according to claim 6 , wherein the porous ceramic material consists of bound pyrogenic silicic acid.