Abstract:
A porous body includes a framework having a three-dimensional network structure, the framework having a body including crystal grains including nickel and cobalt as constituent elements, the cobalt having a proportion in mass of 0.2 or more and 0.8 or less with respect to a total mass of the nickel and the cobalt, the crystal grains having a shorter grain diameter of 2 μm or more, as determined in a first observed image obtained by observing the body of the framework in cross section at a magnification of 200 times.
Abstract:
Provided is a method for producing a negative electrode for an electric storage device, the method comprising the steps of preparing a negative electrode composition comprising a negative electrode active material that reversibly carries a sodium ion, metal sodium, and a liquid dispersion medium for dispersing them; allowing a negative electrode current collector to hold the negative electrode composition; evaporating at least part of the liquid dispersion medium from the negative electrode composition held by the negative electrode current collector, thereby giving a negative electrode precursor comprising the negative electrode active material, the metal sodium, and the negative electrode current collector; and bringing the negative electrode precursor into contact with an electrolyte having sodium ion conductivity, thereby doping the negative electrode active material with sodium eluted from the metal sodium.
Abstract:
Provided is an electrode for a sodium molten-salt battery in which degradation of the electrode can be suppressed even when charging and discharging are repeated, and which has excellent cycle characteristics. The electrode for a sodium molten-salt battery includes a current collector and an electrode mixture adhering to a surface of the current collector, in which the electrode mixture includes an electrode active material and a binder containing a polymer, and the polymer does not contain a fluorine atom. The polymer can include, for example, at least one selected from the group consisting of polyamide resins and polyimide resins or at least one selected from the group consisting of acrylic resins, rubber-like polymers, and cellulose derivatives.
Abstract:
A positive electrode active material for sodium molten salt batteries includes a sodium-containing metal oxide that can electrochemically intercalate and deintercalate sodium ions, wherein a ratio by mass of sodium carbonate is 500 ppm or less. A ratio by mass of sodium carbonate in the positive electrode active material is more preferably 100 ppm or less.
Abstract:
Provided is a sodium molten-salt battery having good charge-discharge cycle characteristics. The sodium molten-salt battery includes a positive electrode that contains a positive electrode active material, a negative electrode that contains a negative electrode active material, and a molten-salt electrolyte that contains a sodium salt and an ionic liquid that dissolves the sodium salt. The negative electrode active material contains non-graphitizable carbon. The ionic liquid is a salt of a bis(sulfonyl)imide anion and a first onium cation that does not cause a Faradaic reaction with the non-graphitizable carbon. The molten-salt electrolyte contains a second onium cation in an amount of 1,000 ppm by mass or less. The second onium cation is represented by a general formula (1): R1R2R3R4N+ where R1 to R4 are each independently a hydrogen atom or a methyl group.
Abstract:
A sodium molten salt battery includes a positive electrode containing a positive electrode active material, a negative electrode containing a negative electrode active material, a separator provided between the positive electrode and the negative electrode, and a molten salt electrolyte having sodium ion conductivity, in which the negative electrode active material contains hard carbon and is pre-doped with sodium ions, and in which when the state of charge is 0%, the potential of the negative electrode is 0.7 V or less with respect to metallic sodium.
Abstract:
A lithium ion secondary battery including a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte, the positive electrode including a positive electrode current collector and a positive electrode active material held on the positive electrode current collector, the positive electrode active material including a lithium-containing transition metal oxide, the negative electrode including a negative electrode current collector and a negative electrode active material held on the negative electrode current collector, the negative electrode active material including at least one selected from the group consisting of lithium metal, lithium alloys, carbon materials, lithium-containing titanium compounds, silicon oxides, silicon alloys, zinc, zinc alloys, tin oxides and tin alloys, the nonaqueous electrolyte including a first salt formed between an organic cation and a first anion and a second salt formed between a lithium ion and a second anion.
Abstract:
The present invention relates to a sodium secondary battery comprising a positive electrode which includes a positive electrode current collector and a positive electrode material, the positive electrode material being carried on the positive electrode current collector, wherein the positive electrode material comprises a positive electrode active material reversibly containing sodium cation; a negative electrode which includes a negative electrode current collector and a negative electrode material, the negative electrode material being carried on the negative electrode current collector, wherein the negative electrode material comprises a negative electrode active material reversibly containing sodium cation; an electrolyte interposed at least between the positive electrode and the negative electrode; and a separator for retaining the electrolyte and separating the positive electrode and the negative electrode from each other; wherein the negative electrode active material is amorphous carbon, and the electrolyte is a molten salt electrolyte which is a mixture of a salt composed of sodium cation and an anion and a salt composed of an organic cation and an anion.
Abstract:
The metal porous body having a framework of a three-dimensional network structure is disclosed. The framework is formed of a metal film, the framework has an interior that is hollow, and the metal film contains titanium metal or titanium alloy as a main component.
Abstract:
A coolant includes a refrigerant, a porous plate-shaped heat insulator, and an enclosure in which the refrigerant and the heat insulator are enclosed in a sealed state, and the heat insulator has a thermal conductivity per unit area of 300 W/(K·m2) or less and a thickness equal to or greater than 0.5 mm and equal to or less than 10.0 mm.