Fuel cell unit, fuel cell stack assembly and method of manufacturing a fuel cell stack assembly

Fuel cell (116) with anode, cathode, electrolyte and contact plate (118) comprises a fluid-guiding element (120) in sheet form with a fluid-tight connection to the contact plate and bounding the fluid space. The contact plate and fluid guide sheet form a two-part shell off the fuel cell that encloses the anode/cathode/ electrolyte unit. Independent claims are also included for: (a) a fuel block as above;and (b) production process for the fuel cell and block.