Electrochemical apparatus with reactant micro-channels

An electrochemical apparatus comprising:

• at least one fuel cell;
• wherein the cell has a solid electrolyte disposed between an oxygen electrode and a fuel electrode, and at least one separator contacting the surface of one of the electrodes opposite the electrolyte;
• wherein the cell defines at least one air manifold and at least one fuel manifold located substantially centrally within the cell;
• wherein at least one electrode defines a micro-channel pattern in communication with one respective air or fuel manifold, wherein at least two of said fuel cells are mounted to each other forming a fuel cell stack;
• wherein at least one of said cells defines a variable cross-section micro-channel within at least one cell layer;
• and, wherein the cell micro-channel net cross-sectional area increases in the direction of reactant flow through the stack.

An electrochemical apparatus comprising:

• at least one fuel cell;
• wherein the cell has a solid electrolyte disposed between an oxygen electrode and a fuel electrode, and at least one separator contacting the surface of one of the electrodes opposite the electrolyte;
• wherein the cell defines at least one air manifold and at least one fuel manifold located substantially centrally within the cell;
• wherein at least one electrode defines a constant cross-section micro-channel pattern in communication with one respective air or fuel manifold;
• wherein the constant cross-section micro-channel pattern is defined by a plurality of columns extending axially from the electrode, and wherein said columns have a diameter of up to about 1 mm.

In a process for the fabrication of a solid oxide fuel cell comprising at least one cell having a cell rim, wherein said cell has a solid electrolyte layer disposed between an oxygen electrode layer and a fuel electrode layer, and at least one separator layer contacting the surface of one of the electrodes opposite said electrolyte;

• wherein each of the layers define at least one air hole and at least one fuel hole and wherein the respective holes within each layer are registerable with one another and define generally central internal air and fuel manifolds;
• the improvement including:
• providing reactant micro-channels in at least one layer, said micro-channels having a width of not more than about 0.5 mm;
• wherein said micro-channels are provided by depositing a selected pattern into the surface of at least one layer;
• wherein electrode material is deposited on at least one layer selected from the group consisting of at least one electrode, the electrolyte and the separator, including forming rows of columns of electrode material defining the micro-channel arranged in a plurality of radially expanding rows;
• and wherein each of said columns have a width, said width increasing in outward radially expanding rows.

In a process for the fabrication of a solid oxide fuel cell comprising at least one cell having a cell rim, wherein said cell has a solid electrolyte layer disposed between an oxygen electrode layer and a fuel electrode layer, and at least one separator layer contacting the surface of one of the electrodes opposite said electrolyte;

• wherein each of the layers define at least one air hole and at least one fuel hole and wherein the respective holes within each layer are registerable with one another and define generally central internal air and fuel manifolds;
• the improvement including:
• providing reactant micro-channels in at least one layer, said micro-channels having a width of not more than about 0.5 mm;
• wherein said micro-channels are provided by depositing a selected pattern into the surface of at least one layer;
• wherein electrode material is deposited on at least one layer selected from the group consisting of at least one electrode, the electrolyte and the separator, including forming rows of columns of electrode material defining the micro-channel arranged in a plurality of radially expanding rows including arranging a plurality of circular columns extending longitudinally outwardly from the respective air or fuel manifold on at least one layer.