A porous body for a fuel cell is interposed between a membrane-electrode assembly (MEA) and a bipolar plate to form a gas channel through which a reactant gas flows in a predetermined direction, the porous body including: a main body disposed to contact the bipolar plate; and a plurality of ribs each including a land portion disposed to contact the MEA and a connecting portion connecting the land portion to the main body, in which an area of the land portion is gradually narrowed from an upstream part to a downstream part of the gas channel.

A porous body for a fuel cell is interposed between a membrane-electrode assembly (MEA) and a bipolar plate to form a gas channel through which a reactant gas flows in a predetermined direction, the porous body including: a main body disposed to contact the bipolar plate; and a plurality of ribs each including a land portion disposed to contact the MEA and a connecting portion connecting the land portion to the main body, in which an area of the land portion is gradually narrowed from an upstream part to a downstream part of the gas channel.

A microwatt fuel cell stack that demonstrates a wide range temperature tolerance, low reactant cross-over and leakage, low internal leakage current, and/or effective water transport is disclosed. Both H.sub.2 and O.sub.2 may be supplied directly to the fuel cell stack (i.e., dead-ended). One-piece gas diffusion electrodes (GDEs) may serve as both the active electrode and manifold port. Water removal may be accomplished by permeation through the membrane to “fins” exposed by notches in the bipolar plates and gaskets.

Described herein are redox active materials based on functionalization of 2,5-di(pyridine-4-yl)thiazolo-[5,4-d]thiazole (Py.sub.2TTz). Also described herein are aqueous organic redox flow batteries that include a first redox active material and a second redox active material comprising a viologen compound or a salt thereof.

Described herein are redox active materials based on functionalization of 2,5-di(pyridine-4-yl)thiazolo-[5,4-d]thiazole (Py.sub.2TTz). Also described herein are aqueous organic redox flow batteries that include a first redox active material and a second redox active material comprising a viologen compound or a salt thereof.

A lightweight electrochemical fuel cell suitable for modular stacking to achieve high output power is described. The electrochemical fuel cell is constructed of a stack of flexible polymer layers sealed at the periphery to create fuel and reactant channels. To scale up the output power, the electrochemical fuel cell is stacked on an external mechanical frame, wrapped-over on to itself in a self-supported 3-dimensional form, or wrapped over around a central mandrel to increase the active area of the fuel cell The electrochemical fuel cell has built in current collecting means and sealed electrodes to eliminate the need for bipolar plates, thereby enabling applications requiring high output power while maintaining a low weight. The thermal management is external to the fuel cell core structure to facilitate modular expansion of the stack to achieve high output power.

A unit cell for a fuel cell includes a membrane electrode body, a pair of gas diffusion layers disposed on both sides of the membrane electrode body, and a pair of separators disposed outside the gas diffusion layers, and including a gas path formed on a surface facing each of the gas diffusion layers and configured to allow reaction gas to flow therethrough, and a coolant path formed on a surface opposite to the surface facing each of the gas diffusion layers and configured to allow coolant to flow therethrough, wherein an inverse forming portion is formed on at least one of both sides of an outermost region in a transverse direction of each of the separators to be bent towards the surface opposite to the surface facing each of the gas diffusion layers.

A lightweight electrochemical fuel cell suitable for modular stacking to achieve high output power is described. The electrochemical fuel cell is constructed of a stack of flexible polymer layers sealed at the periphery to create fuel and reactant channels. To scale up the output power, the electrochemical fuel cell is stacked on an external mechanical frame, wrapped-over on to itself in a self-supported 3-dimensional form, or wrapped over around a central mandrel to increase the active area of the fuel cell The electrochemical fuel cell has built in current collecting means and sealed electrodes to eliminate the need for bipolar plates, thereby enabling applications requiring high output power while maintaining a low weight. The thermal management is external to the fuel cell core structure to facilitate modular expansion of the stack to achieve high output power.

A fuel cell module that suppress deterioration of an electrolyte membrane is provided. The fuel cell module includes a membrane-electrode assembly (MEA) including a polymer electrolyte membrane, an anode catalyst layer disposed on a surface of the membrane, a cathode catalyst layer disposed on the other surface of the membrane, and a pair of gas diffusion layers laminated on the anode catalyst layer and the cathode catalyst layer respectively, a pair of separators sandwiching the MEA; and a sealing member sealing the MEA and each of the pair of separators together. One gas diffusion layer and the sealing member overlaps in a thickness direction within a region including a center-side edge of the sealing member, and the one gas diffusion layer is notched through in the thickness direction at a part of a portion corresponding to the region.

A fuel cell stack includes a power generation cell having a first gas diffusion layer and a dummy cell disposed at an end of the power generation cell and having a second gas diffusion layer with higher thermal conductivity than the first gas diffusion layer. An end plate is fastened at an end of the dummy cell and a heater is interposed between the dummy cell and the end plate.