NOVELTY - The fuel cell stack component (100) is designed to be soldered to another component. It (100) is surface-profiled in a region where a solder track (106) makes contact with further solder. Channel-like depressions in the solder track regions accommodate solder. In the solder track region (106) the component has a network of interconnected, channel-shaped depressions. The component (100) includes an elevation projecting above at least one adjacent depression.    USE - To make and join component of fuel cell stacks into sub assemblies.    ADVANTAGE - The new method forms a soldered connection between stack components, which is reliable and short-circuit free. On becoming molten, the solder follows the surface-profiling with good accuracy, preventing undesired runs which could otherwise form a short circuit. Adhesive force between the soldered regions is improved by profiling which locally increases the specific surface area. Sufficient solder is provided to form a good seal in critical regions. Leakage causing catastrophic failure is prevented.    DETAILED DESCRIPTION - At least one elevation is of locally-confined construction. An upper side of at least one elevation in the solder track region is at the same level as the upper side of a solder track edge region on the other component. At least one elevation in the solder track region (106) is diamond-shaped, circular, oval or polygonal. An outer contour of the solder track region (106) is formed by the edge of at least one depression, at least sectionally. The outer contour of the solder track region (106) runs essentially in a straight line. It runs parallel to the outer contours of the elevations arranged on the solder track regions (106). Surface-profiling is impressed into or etched into the solder track region (106) of the component. A fuel cell stack sub-assembly which is also claimed, comprises a first component (100) as described and at least one second component soldered to it by means of a solder track (108). To solder a first component (100) of a fuel stack to a second component, the following stages are used. A solder track region (106) is provided on the first component. This is surface-profiled with at least one depression. The depression is filled with solder and the two components are soldered together using this solder. AN INDEPENDENT CLAIM IS INCLUDED FOR the method of soldering the components together.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic plan view of a component of a fuel cell stack, which has been provided with solder tracks.    fuel cell stack component (100)    solder track (106)    solder track (108)    outer edge (114)    annular closed outer solder track region (106')