In an embodiment, a fuel cell includes: a flexible substrate including a first fuel-tolerant material; a fitting on the flexible substrate, the fitting including first openings extending through an outer portion of the fitting; a primer coating on the outer portion of the fitting, the primer coating including a second fuel-tolerant material; first yarns strung through the first openings of the fitting, the first yarns stitched into the flexible substrate; and an encapsulant encapsulating the first yarns, the primer coating, and the outer portion of the fitting, the encapsulant disposed on the flexible substrate, the encapsulant including a third fuel-tolerant material, the third fuel-tolerant material chemically bonded to the second fuel-tolerant material and the first fuel-tolerant material.

A benthic microbial fuel cell comprising: a nonconductive frame having an upper end and a lower end; a plurality of anodes, wherein each anode is a conductive plate having a top section and a bottom edge; a plurality of conductive, threaded rods disposed perpendicularly to the anode plates and configured to secure the top sections of the anodes to the lower end of the frame and to hold the plates in a substantially parallel orientation with respect to each other such that none of the plates are in direct contact with each other; and a plurality of cathodes, wherein each cathode is made of carbon cloth connected to the upper end of the frame.

An aircraft, such as a rotorcraft, may have (an) area(s) designated to house (a) fuel cell(s) and (an) aircraft structure(s) that may translate, during a drop impact of the aircraft, into the area(s) designated to house the fuel cell(s). (A) shaped fuel cell(s) may be provided and deployed therein, in accordance with the present systems and methods. Each respective shaped fuel cell may define (a) respective through-void(s) defined through the respective shaped fuel cell, and/or (an) respective edge cavit(y)(ies) defined along an edge of the shaped fuel cell, wherein the respective through-void(s) and/or the respective edge cavit(y)(ies) correspond to the respective aircraft structure(s) that may translate, during the drop impact of the aircraft, into the area(s) of the aircraft designated to house the respective fuel cell(s) to receive and accommodate the respective structure(s) during the drop impact.

A fuel cell system includes a plurality of fuel cell units each configured to generate lower-voltage DC power. The fuel cell system includes a plurality of DC-DC converters each electrically connected to each of the fuel cell units and configured to convert the lower-voltage DC power to higher-voltage DC power. The fuel cell system includes a primary load power conversion unit electrically connected to the plurality of DC-DC converters and configured to output a primary load. The fuel cell system includes an auxiliary load power conversion unit electrically connected to the plurality of DC-DC converters and configured to output an auxiliary load.

A three-dimensional electrode array for use in electrochemical cells, fuel cells, capacitors, supercapacitors, flow batteries, metal-air batteries and semi-solid batteries.

An energy recovery converter for exhaust gases or waste heat is provided. The converter includes a membrane electrode assembly (MEA), an exhaust gas having a first molecular oxygen content, and an external electrical load. The MEA includes a first electrode, a second electrode and an oxygen ion conductive membrane sandwiched between the first and second electrodes. Each of the first and second electrodes includes at least one oxidation catalyst configured to promote an electrochemical reaction. The second electrode of the MEA is exposed to the exhaust gas and the first electrode of the MEA is exposed to a gas having a second molecular oxygen content. The second molecular oxygen content is higher than the first molecular oxygen content. The external electrical load is connected between the first and second electrodes of the MEA.

In an embodiment, a fuel cell includes: a flexible substrate including a first fuel-tolerant material; a fitting on the flexible substrate, the fitting including first openings extending through an outer portion of the fitting; a primer coating on the outer portion of the fitting, the primer coating including a second fuel-tolerant material; first yarns strung through the first openings of the fitting, the first yarns stitched into the flexible substrate; and an encapsulant encapsulating the first yarns, the primer coating, and the outer portion of the fitting, the encapsulant disposed on the flexible substrate, the encapsulant including a third fuel-tolerant material, the third fuel-tolerant material chemically bonded to the second fuel-tolerant material and the first fuel-tolerant material.

A fuel cell module includes a plurality of power generation cells. The plurality of power generation cells are stacked together in a circle, and a tightening load is applied to the plurality of power generation cells in a circumferential direction. Each of the plurality of power generation cells includes a V-shaped electrically conductive base plate. A first reactant gas flow field is provided between power generation cells that are adjacent to each other. A ridge protruding outward is provided in the base plate to provide the first reactant gas flow field by the ridge, and insulating material is provided on the ridge.

In an embodiment, a fuel cell includes: a flexible substrate including a first fuel-tolerant material; a fitting on the flexible substrate, the fitting including first openings extending through an outer portion of the fitting; a primer coating on the outer portion of the fitting, the primer coating including a second fuel-tolerant material; first yarns strung through the first openings of the fitting, the first yarns stitched into the flexible substrate; and an encapsulant encapsulating the first yarns, the primer coating, and the outer portion of the fitting, the encapsulant disposed on the flexible substrate, the encapsulant including a third fuel-tolerant material, the third fuel-tolerant material chemically bonded to the second fuel-tolerant material and the first fuel-tolerant material.

A process for manufacturing a flow guide for an electrochemical reactor, including providing a substrate; on a first face of the substrate, printing a layer of electrically conductive ink by applying a shear stress to this layer, the viscosity of the printed ink being comprised between 70 and 500 Pa.Math.s for a shear rate of 0.1 s.sup.−1, and the viscosity of the printed ink being comprised between 2.5 and 7 Pa.Math.s for a shear rate of 100 s.sup.1, the layer of ink being printed to form a pattern including ribs delineating flow channels.