Methods and systems directed to recovery of lithium (e.g., lithium salts) from liquid streams are provided. In some embodiments, methods relate to obtaining lithium (e.g., as a solid lithium salt) by removing at least a portion of liquid from a feed stream to form a concentrated stream with respect to solubilized lithium cations. Liquid removal may include transporting at least a portion of the feed stream to an osmotic unit and/or a humidifier. Some methods include removing impurities (e.g., non-lithium cations) from the concentrated stream (e.g., via precipitation and/or crystallization). In some embodiments, solutions containing solubilized lithium cations and anions are electrochemically-treated such that first solubilized anions are replaced with second, different anions. In some embodiments, solid lithium salt containing at least a portion of the lithium cations and the second anions is obtained (e.g., via precipitation and/or crystallization following concentration of the electrochemically-treated solution in a humidifier).

A method and system provide a fitting system for a flexible fuel cell of an aircraft. The fitting system may include a flexible fuel cell and a fitting. The fitting may have a peripheral flange with a series of slots spaced about the flange. A series of fabric strips may be threaded into the slots of the fitting and one or more adhesives may couple the fabric strips to the fuel cell. The fabric strips may extend out around the periphery of the fitting to provide a uniform contact surface area with the fuel cell. The fabric strips may be separated by fuel cell material. The fabric strips may be made from one or more materials for enclosing or holding fuel. The fitting may further include threaded holes wherein the threaded holes may receive fasteners to couple the fitting to the fuel equipment of an aircraft.

A sheet attaching apparatus includes a gripping mechanism that grips one end portion, in a longitudinal direction, of a first sheet that has been drawn out from a first supply roll; a moving mechanism that allows the first sheet to be attached to a second sheet by moving the gripping mechanism to cause the first sheet to approach and contact the second sheet that passes through an attaching portion provided in a feeding path; and a releasing mechanism that releases a grip of the gripping mechanism on the first sheet, after the first sheet has contacted the second sheet.

A fuel cell system including: a first fuel cell performing power generation using a fuel gas; a separation membrane separating at least one of carbon dioxide or water vapor from an anode off gas discharged from the first fuel cell; a second fuel cell disposed in the downstream of the separation membrane and performing power generation using the anode off gas, the anode off gas having at least one of carbon dioxide or water vapor separated therefrom; and a distribution channel disposed on a permeation side of the separation membrane and distributing any of the following: a raw material gas serving as the fuel gas to be reformed and used for the power generation of the first fuel cell, a cathode gas including oxygen to be used for the power generation of the first fuel cell, an anode off gas discharged from the second fuel cell, a cathode off gas discharged from the first fuel cell and to be supplied to the second fuel cell, or a cathode off gas discharged from the second fuel cell, in which at least one of permeability coefficient ratio α1 of the separation membrane or permeability coefficient ratio α2 of the separation membrane is 30 or higher.

A fuel cell system including: a first fuel cell performing power generation using a fuel gas; a separation membrane separating at least one of carbon dioxide or water vapor from an anode off gas discharged from the first fuel cell; a second fuel cell disposed in the downstream of the separation membrane and performing power generation using the anode off gas, the anode off gas having at least one of carbon dioxide or water vapor separated therefrom; and a distribution channel disposed on a permeation side of the separation membrane and distributing any of the following: a raw material gas serving as the fuel gas to be reformed and used for the power generation of the first fuel cell, a cathode gas including oxygen to be used for the power generation of the first fuel cell, an anode off gas discharged from the second fuel cell, a cathode off gas discharged from the first fuel cell and to be supplied to the second fuel cell, or a cathode off gas discharged from the second fuel cell, in which at least one of permeability coefficient ratio α1 of the separation membrane or permeability coefficient ratio α2 of the separation membrane is 30 or higher.

Methods for forming a metal oxide electrolyte improve ionic conductivity. Some of those methods involve applying a first metal compound to a substrate, converting that metal compound to a metal oxide, applying a different metal compound to the metal oxide, and converting the different metal compound to form a second metal oxide. That substrate may be in nanobar form that conforms to an orientation imparted by a magnetic field or an electric field applied before or during the converting. Electrolytes so formed can be used in solid oxide fuel cells, electrolyzers, and sensors, among other applications.

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 lightweight, high power density, fault-tolerant fuel cell system, method, and apparatus for full-scale clean fuel electric-powered aircraft having a fuel cell module including a plurality of fuel cells working together to process gaseous oxygen from air compressed by turbochargers, superchargers, blowers or local oxygen supply and gaseous hydrogen from liquid hydrogen transformed by heat exchangers, with an electrical circuit configured to collect electrons from the plurality of hydrogen fuel cells to supply voltage and current to motor controllers commanded by autopilot control units configured to select and control an amount and distribution of electrical voltage and torque or current for each of the plurality of motor and propeller assemblies, wherein electrons returning from the electrical circuit combine with oxygen in the compressed air to form oxygen ions, then the protons combine with oxygen ions to form H.sub.2O molecules and heat.

A sealing structure of a humidifier includes a main structure, a left end cover, and a right end cover. The left end cover and the right end cover are arranged on left and right end faces of the main structure, respectively. A dry air inlet tube is connected to a top end face of the left end cover, and a dry air outlet tube is connected to a top end face of the right end cover. A wet air outlet tube and a wet air inlet tube are connected to left and right sides of a top end face of the main structure, respectively. Membrane tubes are arranged on an inner side of the main structure. Potting resin layers are arranged on both ends of the membrane tubes. High-temperature resistant sealant layers are arranged at connecting portions between each end cover and the main structure.

A proton exchange membrane fuel cell includes an anode catalyst layer, a cathode catalyst layer, a proton exchange membrane separating the anode catalyst layer from the cathode catalyst layer, an oxygen inlet configured to supply oxygen to the cathode catalyst layer, and a hydrogen inlet separate from the oxygen inlet and configured to supply hydrogen to the anode catalyst layer. The fuel cell is operable to convert the hydrogen from the hydrogen inlet to hydrogen ions at the anode catalyst layer and to produce an H2O byproduct at the cathode catalyst layer where the oxygen reacts with the hydrogen ions. The fuel cell includes a water outlet for the H2O byproduct that is separate from the oxygen inlet.