Adjacent individual cells of a fuel cell are connected in series by intermediate connecting parts. Each connecting part is formed by a branch made from an electrically conducting material and extending the first current collector of a cell perpendicularly and connected to the second current collector of the adjacent cell. Each first current collector is moreover formed by an electrically insulating porous matrix incorporating said electrically conducting material, and the first current collectors of two adjacent cells are separated by an area of electrically insulating porous material, said electrically insulating porous material being identical to that forming the porous matrix of said first current collectors. Series connection between the individual cells of such a fuel cell is thereby easy and quick to implement.