Provided is an electrochemical device including a negative electrode, a positive electrode, and a separator disposed between the negative electrode and the positive electrode. In the electrochemical device, the negative electrode is an electrode containing magnesium, and is in contact with a fullerene analogue-containing layer containing a fullerene analogue. The electrolytic solution of the electrochemical device includes a solvent and a magnesium salt contained in the solvent.

A cell for water electrolysis/fuel cell power generation which includes a flow path configured to supply or discharge water in a first direction substantially perpendicular to a stacking direction of the cell; an oxygen-containing gas flow path configured to discharge or supply an oxygen-containing gas in a second direction substantially perpendicular to the stacking direction of the cell; and a hydrogen-containing gas flow path configured to discharge or supply the hydrogen-containing gas in a third direction substantially perpendicular to the stacking direction of the cell. Each of the oxygen-side electrode layer and the hydrogen-side electrode layer is an electrode layer having water repellency.

A method of generating electrical power or hydrogen from thermal energy is disclosed. The method includes separating, by a selectively permeable membrane, a first saline solution from a second saline solution, receiving, by the first saline solution and/or the second saline solution, thermal energy from a heat source, and mixing the first saline solution and the second saline solution in a controlled manner, capturing at least some salinity-gradient energy as electrical power as the salinity difference between the first saline solution and the second saline solution decreases. The method further includes transferring, by a heat pump, thermal energy from the first saline solution to the second saline solution, causing the salinity difference between the first saline solution and the second saline solution to increase.

Self-charging electrochemical cells, including self-charging batteries that incorporate such self-charging electrochemical cells, the electrochemical cells including a cathode including a cathode active material, an electrolyte including a solvent and a salt dissolved in the solvent, the electrolyte being in contact with the cathode, where the cathode active material is transformed into a discharge product during or after a discharge of the self-charging electrochemical cell and a solubility of the cathode active material in the electrolyte is less than a solubility of the discharge product in the electrolyte.

Systems and methods for operating an electric energy storage device are described. The systems and methods may generate a state of charge estimate that is based on negative electrode plating. An overall state of charge may be determined from the state of charge estimate that is based on negative electrode plating and a state of charge estimate that is not based on negative electrode plating.

Method and apparatus for generating green electrical power. During a hydrogen gas storage mode, an electrolyzer generates a stream of hydrogen gas from water supplied by a water source and using power from an input power source. A hydrogen tank temporarily stores the stream of hydrogen. During a power generation mode, a fuel cell converts the stream of hydrogen gas from the tank into output electrical power by combining the hydrogen with oxygen. An inverter conditions and supplies the electrical power to a local load. A controller circuit uses a system parameter to adaptively switch between the storage mode and the power generation mode. In some cases, external power is supplied during the generation and storage of the hydrogen gas from an electrical grid or a local renewable source such as a set of solar panels. Respective grid-tied, solar-tied, grid-only, off-grid, and electric vehicle charging configurations are provided.

A flow battery includes a negative electrode, a positive electrode, a first liquid in contact with the negative electrode, a second liquid in contact with the positive electrode, and a lithium-ion-conductive film disposed between the first liquid and the second liquid. At least one of the first liquid or the second liquid contains a redox species and lithium ions. The lithium-ion-conductive film includes an inorganic member containing zeolite.

Ionic cyclic nitroxyl radical oligomers, methods of making the ionic cyclic nitroxyl radical oligomers, and electrochemical cells, such as aqueous organic redox flow batteries (AORFBs) that use the ionic nitroxyl radical oligomers as catholytes are provided. The oligomers are larger than individual cyclic nitroxyl radical molecules, but maintain a high density nitroxyl radical groups within the molecule. As a result, when the oligomers are used as catholytes in an AORFB, they are able to reduce catholyte permeation through the ion-conducting membrane, while providing a high volumetric capacity and cycling stability.

Aqueous anolytes for redox flow batteries are disclosed. The anolytes include a fluorenone-fluorenol derivative, an additive comprising an organic compound including one or more proton acceptor groups, an alkali metal hydroxide, and water. The additive functions as a homogeneous organocatalyst and may increase the current density of an aqueous redox flow battery including the anolyte.

A system for high-temperature reversible electrolysis of water, characterised in that it includes: a high-temperature reversible electrolyser, configured to operate in SOEC (solid oxide electrolyser cell) mode to produce hydrogen and store electricity, and/or in SOFC (solid oxide fuel cell) mode to withdraw hydrogen and produce electricity; a hydride tank, thermally coupled with the reversible electrolyser, the system being configured to allow the recovery of heat released by the hydride tank during hydrogen absorption in order to produce pressurised steam intended for entering the reversible electrolyser in SOEC mode, and to allow the recovery of heat released by the one or more outgoing streams from the reversible electrolyser in SOFC mode so as to allow the desorption of hydrogen from the hydride tank.