A positive electrode active material having a crystal structure that is unlikely to be broken by repeated charging and discharging is provided. A positive electrode active material with high charge and discharge capacity is provided. A positive electrode active material including lithium, cobalt, nickel, magnesium, and oxygen, in which the a-axis lattice constant of an outermost surface layer of the positive electrode active material is larger than the a-axis lattice constant of an inner portion and in which the c-axis lattice constant of the outermost surface layer is larger than the c-axis lattice constant of the inner portion. A rate of change between the a-axis lattice constant of the outermost surface layer and the a-axis lattice constant of the inner portion is preferably larger than 0 and less than or equal to 0.12, and a rate of change between the c-axis lattice constant of the outermost surface layer and the c-axis lattice constant of the inner portion is preferably larger than 0 and less than or equal to 0.18.

A clad porous metal substrate for use in a metal-supported electrochemical cell, wherein a metal support layer of defined porosity is clad on top and bottom sides with a layer containing a metal and/or a metal oxide. A metal-supported electrochemical half-cell and a metal-supported electrochemical cell are also described.

Me-N—C catalysts, wherein Me can include a transition metal, Mn, Fe, Co, or a combination of metals with Me-INU moieties located at the exterior surface of the Me-N—C catalysts are produced by a chemical vapor deposition synthesis. The synthesis methods can utilize non-solid-contact pyrolysis wherein a metal salt can be vaporized. Gaseous metal from the vaporized metal salt can displace a metal M from the N—C zeolitic imidazolate framework. The non-solid-contact pyrolysis does not mix solid iron precursors (e.g., Me=Mn, Fe, or Co) with the solid N—C zeolitic imidazolate framework precursors during or before the synthesis, which improves the process compared to conventional methods.

The invention is a cathode arrangement comprising a cathode housing (20) defining a space (16) for cathode material and comprising a cathode housing wall being permeable to an electrolyte, and a collector member made of carbon, having a first end part extending into the space (16) for cathode material and a second end part extending outside the space (16) for cathode material, and cathode particles (10), having a cylindric shape with a diameter of 2-5 mm and being extruded from carbon, are arranged in the space (16) for cathode material. The invention is, furthermore, an energy cell comprising the cathode arrangement, an arrangement for processing hydrogen gas comprising the cathode arrangement and use the energy cell applying seawater or salt water as an electrolyte. Furthermore, the invention is a method for manufacturing the cathode arrangement.

Methods and systems are provided for transporting and hydrating a redox flow battery system with a portable field hydration system. In one example, the redox flow battery system may be hydrated with the portable field hydration system in a dry state, in the absence of liquids. In this way, a redox flow battery system may be assembled and transported from a battery manufacturing facility to an end-use location off-site while the redox flow battery system is in the dry state, thereby reducing shipping costs, design complexities, as well as logistical and environmental concerns.

A cathode configured for use within a fuel cell system is provided. The cathode includes a cathode substrate. The cathode further includes a coating disposed upon the cathode substrate and including a fluorocarbon polymer additive configured for sintering at a temperature of less than 200° C. The fluorocarbon polymer additive may be mixed with a catalyst ink coating or may be applied separately as a topcoat layer.

A cathode includes: a mixed conductive layer, wherein the mixed conductive layer includes a core-shell structured particle having a core portion including a solid electrolyte and a shell portion including an electronic conductor, wherein the cathode is configured to use oxygen as a cathode active material.

Provided is an electrochemical oxygen reduction catalyst comprising platinum-containing nanoparticles and at least one member selected from the group consisting of a specific polymer containing a melamine compound as a monomer and a specific melamine compound, the electrochemical oxygen reduction catalyst having not only high oxygen reduction activity (low overvoltage), but also high durability at 70 to 85° C., which are practical temperature conditions.

A metal-air battery includes: a cathode formed of a co-continuous body having a three dimensional network structure formed by an integrated plurality of nanostructures having branches; a foil- or plate-like anode formed of a metal; a separator that absorbs a liquid, which is to be an electrolytic solution; and a foil- or plate-like current collector formed of a metal. The metal-air battery is formed with a wound structure in which the current collector, the cathode, the separator, the anode, and the separator are superimposed and wound in this order.

Hybrid catalyst suitable for use in a proton exchange membrane fuel cell and method of preparing same. In one embodiment, the hybrid catalyst is iron-free and includes an Mn—N—C support and platinum-containing nanoparticles that are dispersed on the Mn—N—C support. The Mn—N—C support preferably comprises atomically dispersed and nitrogen coordinated MnN.sub.4 moieties and has a particle size of about 30 to 200 nm. The platinum-containing nanoparticles preferably have a particle size ranging from about 2 to 8 nm and are made of platinum or a platinum-cobalt intermetallic alloy, such as a cubic L1.sub.2 Pt.sub.3Co alloy or a tetragonal L1.sub.0 PtCo alloy. The hybrid catalyst may be made by combining a quantity of a hexachloroplatinic acid solution with a quantity of an Mn—N—C support, sonicating the mixture in an ice bath, freeze-drying the sonicated product, calcinating the freeze-dried product under a forming gas, and heating the calcinated product.