An electrochemical device can include a cathode layer including an ionic conductor material and an electronic conductor material. The cathode layer can include a ratio of (Vi/Ve) of a volume of the ionic conductor material (Vi) to a volume of the electronic conductor material (Ve) of at least 1.3. In an embodiment, the cathode layer can include a median surface diffusion length (Ls) greater than 0.33 microns. In an embodiment, the cathode layer can include a cathode functional layer.

A battery includes: an electrode group including an air electrode and a negative electrode that are stacked with a separator interposed therebetween; and a container housing the electrode group together with an alkaline electrolyte liquid. The air electrode includes a catalyst for an air electrode. This catalyst for an air electrode is a catalyst for an air electrode including an oxide containing at least bismuth (Bi), ruthenium (Ru), sodium (Na), and oxygen, and Na/(Ru+Bi+Na) representing an atomic ratio of the sodium to a sum of the bismuth, the ruthenium, and the sodium is 0.126 or more and 0.145 or less.

An air electrode catalyst for an air secondary battery includes a pyrochlore-type composite oxide having two or more crystal structures having a different amount of oxygen. A battery, according to some embodiments, includes an electrode group including an air electrode and a negative electrode stacked with a separator therebetween, and a container accommodating the electrode group along with an alkali electrolyte solution, wherein the air electrode includes the air electrode catalyst. The air electrode catalyst may have a pyrochlore-type composite oxide having a crystal structure represented by Bi.sub.2Ru.sub.2O.sub.6.92 and a crystal structure represented by Bi.sub.2Ru.sub.2O.sub.7.33.

A cathode configured to use oxygen as a cathode active material includes: a porous electrically conductive framework substrate; and a coating layer disposed on a surface of the porous electrically conductive framework substrate, wherein the coating layer includes at least one of a lithium-containing metal oxide or a composite including a lithium-containing metal oxide, and wherein a porosity of the porous electrically conductive framework substrate is about 70 percent to about 99 percent, based on a total volume of the cathode, and an areal resistance of the porous electrically conductive framework substrate is about 0.01 milliohms per square centimeter to about 100 milliohms per square centimeter.

A high-performance positive electrode catalyst for a metal-air battery is disclosed, which is composed of transition metal nitride-transition metal oxide heterogeneous particles and a mesoporous carbon matrix. The nano heterogeneous particles, which are 10-50% based on the total mass of the catalyst, are dispersed in the mesoporous carbon matrix; and the oxide is 10-100% based on the heterogeneous particles. A preparation method of the catalyst includes: treating mesoporous carbon with a strong acid solution to obtain surface-functionalized mesoporous carbon; immersing the surface-functionalized mesoporous carbon in an aqueous solution of a transition metal salt, and stirring and washing; adding ammonia water and stirring to enable a confined complexation reaction; washing again, and vacuum drying; and calcining the product in an inert atmosphere or a vacuum condition.

Disclosed herein is a cathode structure, a membrane-electrode assembly including the same, and a fuel cell including the same.

Core-shell nanoparticles having a solid core comprising a first metal and a shell comprising a second metal disposed at least a portion of the exterior surface of the core. The core-shell nanoparticles comprise a non-precious transition metal and the second metal comprises a precious metal or semi-precious metal. The core-shell nanoparticles can be used to catalyze oxygen reduction reactions. Also provided are compositions comprising the core-shell nanoparticles, methods of making same, and devices of same.

The present invention provides a supported metal catalyst with excellent effectiveness factor of active metal particles which are also free from deactivation by contacting with ionomer.

According to the present invention, provided is a supported metal catalyst, comprising a support that is a collective body of conductive particles; and dispersed active metal particles supported on the conductive particles, wherein the conductive particles include a plurality of pores, an average entrance pore diameter of the pores is 1 to 20 nm, a standard deviation of the average entrance pore diameter is equal to or less than 50% of the average entrance pore diameter, a number fraction of the active metal particles supported in a surface layer region of the conductive particles divided by the total number of the active metal particles is equal to or more than 50%, and the surface layer region is a region on a surface of the conductive particles or a region in the pores within a depth of 15 nm from the surface.

An object of the present invention is to provide a membrane for a redox flow battery which is prevented from being curled and exhibits high power efficiency, a membrane electrode assembly for a redox flow battery, a cell for a redox flow battery, and a redox flow battery. The object can be attained by a membrane for a redox flow battery, comprising a first ion-exchange resin layer, an anion-exchange resin layer containing an anion-exchange compound, and a second ion-exchange resin layer in the presented order, wherein a value obtained by dividing a thickness of the first ion-exchange resin layer by a thickness of the second ion-exchange resin layer is 0.7 or more and 1.3 or less, and a thickness of the anion-exchange resin layer is 0.02 μm or larger and 3 μm or smaller.

A zinc based rechargeable redox static energy storage device includes a cathode including a carbon material—binder composition and an anode including carbon material—Zinc material—binder composition both infused with an eutectic electrolyte comprising one or more inorganic transition metal salt(s) of zinc, one or more Metal hydroxide(s) and eutectic solvent comprising derivative(s) of methanesulfonic acid, ammonium salt(s) and hydrogen bond donor(s); a separator separating the cathode and anode so that the ion exchange carries in between the cathode and anode through ionic permeability; and current collector connected with the cathode and anode respectively.