Stack Configuration and Sealing

Reactant gases need to be supplied in parallel to all cells in the same stack via common manifolds. Some stack designs rely on external manifolds, whereas others use internal manifolds. 

In internal manifolding, the preferred method of sealing is to use the electrolyte matrix itself as a sealant. The electrolyte matrix forms a wet seal in the manifold areas around the gas ducts. In internally manifolded stacks, the entire periphery of the cell may be sealed in this way. It is possible to seal the manifolds with separate gaskets and to extend the matrix only over the active cell area, but this method is rarely used. 

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