A separator for a fuel cell includes a facing surface configured to face a power generating unit of the fuel cell. Groove passages and ribs that protrude toward the power generating unit are provided on the facing surface. At least one of the ribs includes at least one recess in a center of the rib in an arrangement direction of the groove passages. The recess includes a bottom surface, which faces the power generating unit, and two inner side surfaces, which rise from opposite ends in the arrangement direction of the bottom surface. The two inner side surfaces are inclined such that a given point on each inner side surface separates further away from the bottom surface in the arrangement direction as that point approaches the power generating unit in a direction in which the power generating unit and the separator face each other.

A separator for a fuel cell includes a facing surface configured to face a power generating unit of the fuel cell. Groove passages and ribs that protrude toward the power generating unit are provided on the facing surface. At least one of the ribs includes at least one recess in a center of the rib in an arrangement direction of the groove passages. The recess includes a bottom surface, which faces the power generating unit, and two inner side surfaces, which rise from opposite ends in the arrangement direction of the bottom surface. The two inner side surfaces are inclined such that a given point on each inner side surface separates further away from the bottom surface in the arrangement direction as that point approaches the power generating unit in a direction in which the power generating unit and the separator face each other.

The presently disclosed subject matter relates to devices, systems, and methods of producing an improved fluid flow assembly and liquid/gas diffusion layer in solid polymer electrolyte electrochemical cells. In one aspect, a fluid flow assembly for a polymer electrolyte water electrolyzer includes a flow field having an inlet, an outlet, and a plurality of discrete lands arranged within the flow field. A liquid/gas diffusion layer is positioned in communication with the flow field between the inlet and the outlet, the liquid/gas diffusion layer having a solid substrate through which a plurality of pores is formed. The disclosed bipolar plate flow field and liquid/gas diffusion layer could work together or separately with other types of porous transport layers or bipolar plates to enhance the water/gas transport. In these configurations, the lands can be arranged and configured such that the plurality of pores are substantially unobstructed by the lands.

The presently disclosed subject matter relates to devices, systems, and methods of producing an improved fluid flow assembly and liquid/gas diffusion layer in solid polymer electrolyte electrochemical cells. In one aspect, a fluid flow assembly for a polymer electrolyte water electrolyzer includes a flow field having an inlet, an outlet, and a plurality of discrete lands arranged within the flow field. A liquid/gas diffusion layer is positioned in communication with the flow field between the inlet and the outlet, the liquid/gas diffusion layer having a solid substrate through which a plurality of pores is formed. The disclosed bipolar plate flow field and liquid/gas diffusion layer could work together or separately with other types of porous transport layers or bipolar plates to enhance the water/gas transport. In these configurations, the lands can be arranged and configured such that the plurality of pores are substantially unobstructed by the lands.

A separator for a fuel cell includes protrusions spaced apart from each other. The protrusions are configured to contact a power generation portion. The separator includes a gas passage that extends between two adjacent ones of the protrusions. The gas passage includes ribs that protrude toward the power generation portion. The ribs include first ribs spaced apart from each other in an arrangement direction of the protrusions and a second rib located between adjacent ones of the first ribs in the arrangement direction. A downstream end of each of the first ribs includes a separated portion separated from the power generation portion. An upstream end of the second rib includes an inclined portion inclined so as to become closer to the power generation portion toward a downstream side. At least part of the inclined portion is located downstream of at least part of the separated portion.

A separator for a fuel cell includes protrusions spaced apart from each other. The protrusions are configured to contact a power generation portion. The separator includes a gas passage that extends between two adjacent ones of the protrusions. The gas passage includes ribs that protrude toward the power generation portion. The ribs include first ribs spaced apart from each other in an arrangement direction of the protrusions and a second rib located between adjacent ones of the first ribs in the arrangement direction. A downstream end of each of the first ribs includes a separated portion separated from the power generation portion. An upstream end of the second rib includes an inclined portion inclined so as to become closer to the power generation portion toward a downstream side. At least part of the inclined portion is located downstream of at least part of the separated portion.

A bipolar plate with an enhanced fluid flow field design is provided for a fuel cell. The bipolar plate includes an inlet, an outlet, and a flow field having a pattern defining a plurality of microchannels configured to provide fluid communication between the inlet and the outlet. The pattern is designed using an inverse permeability field, and is based on a reaction-diffusion algorithm to model channel spacing, thereby providing a variable pitch microchannel pattern to direct fluid from the inlet to the outlet. In various aspects, the reaction-diffusion algorithm utilize Gray-Scott reaction-diffusion equations, which may be used to obtain an anisotropic microchannel layout. The variable pitch microchannel pattern may include a channel spacing based on effective medium theory.

A bipolar plate with an enhanced fluid flow field design is provided for a fuel cell. The bipolar plate includes an inlet, an outlet, and a flow field having a pattern defining a plurality of microchannels configured to provide fluid communication between the inlet and the outlet. The pattern is designed using an inverse permeability field, and is based on a reaction-diffusion algorithm to model channel spacing, thereby providing a variable pitch microchannel pattern to direct fluid from the inlet to the outlet. In various aspects, the reaction-diffusion algorithm utilize Gray-Scott reaction-diffusion equations, which may be used to obtain an anisotropic microchannel layout. The variable pitch microchannel pattern may include a channel spacing based on effective medium theory.

A fuel cell module includes a stack including a plurality of fuel cells stacked together, at least one dummy cell in contact with the stack at an end portion of the stack in a stacking direction, a reactant gas supply path configured to supply a reactant gas that is either a fuel gas or an oxidant gas to the fuel cells and the dummy cell, and a reactant gas discharge path in communication with the fuel cells and the dummy cell. The fuel cells and the dummy cell each include a reactant gas flow path configured to cause the reactant gas from the reactant gas supply path to flow toward the reactant gas discharge path. Pressure loss of the reactant gas flow path of the dummy cell is smaller than pressure loss of the reactant gas flow path of the fuel cells.

A fuel cell module includes a stack including a plurality of fuel cells stacked together, at least one dummy cell in contact with the stack at an end portion of the stack in a stacking direction, a reactant gas supply path configured to supply a reactant gas that is either a fuel gas or an oxidant gas to the fuel cells and the dummy cell, and a reactant gas discharge path in communication with the fuel cells and the dummy cell. The fuel cells and the dummy cell each include a reactant gas flow path configured to cause the reactant gas from the reactant gas supply path to flow toward the reactant gas discharge path. Pressure loss of the reactant gas flow path of the dummy cell is smaller than pressure loss of the reactant gas flow path of the fuel cells.