Abstract: In a recovery control method for a secondary battery that includes a positive electrode containing a positive electrode active material, a solid electrolyte, and a negative electrode containing a negative electrode active material containing at least a lithium metal or a lithium alloy, and is fastened from an outside, the recovery control method includes: measuring cell resistance of the secondary battery; calculating a recovery limit resistance value indicating an upper limit value of resistance that ensures recovering the secondary battery from a depth of charge/discharge of the secondary battery, a cell temperature of the secondary battery, and a pressure applied to the secondary battery; and inhibiting charging/discharging the secondary battery and executing recovery control that recovers the secondary battery when a resistance value of the cell resistance is equal to or less than the recovery limit resistance value.

Abstract: In a recovery control method for a secondary battery that includes a positive electrode containing a positive electrode active material, a solid electrolyte, and a negative electrode containing a negative electrode active material containing at least a lithium metal or a lithium alloy, and is fastened from an outside, the recovery control method includes: measuring cell resistance of the secondary battery; calculating a recovery limit resistance value indicating an upper limit value of resistance that ensures recovering the secondary battery from a depth of charge/discharge of the secondary battery, a cell temperature of the secondary battery, and a pressure applied to the secondary battery; and inhibiting charging/discharging the secondary battery and executing recovery control that recovers the secondary battery when a resistance value of the cell resistance is equal to or less than the recovery limit resistance value.

Abstract: A method for manufacturing a metal gas diffusion layer made of a metal porous body, the method includes forming a conductive layer of carbon film layer on the metal porous body, and forming a water-repellent layer on the metal porous body formed with the conductive layer. The forming a water-repellent layer includes coating a solution containing a fluorine resin which constitutes the water-repellent layer and a volatile component which does not constitute the water-repellent layer on the metal porous body, and heat-treating the metal porous body coated with the solution at or above a temperature at which a component which contains the volatile component and which does not constitute the water-repellent layer contained in the solution and less than a temperature at which an electrical resistance of the conductive layer is increased and electron conductivity is deteriorated to thereby form the water-repellent layer composed of the fluorine resin.

Abstract: A method for manufacturing a metal gas diffusion layer made of a metal porous body, the method includes forming a conductive layer of carbon film layer on the metal porous body, and forming a water-repellent layer on the metal porous body formed with the conductive layer. The forming a water-repellent layer includes coating a solution containing a fluorine resin which constitutes the water-repellent layer and a volatile component which does not constitute the water-repellent layer on the metal porous body, and heat-treating the metal porous body coated with the solution at or above a temperature at which a component which contains the volatile component and which does not constitute the water-repellent layer contained in the solution and less than a temperature at which an electrical resistance of the conductive layer is increased and electron conductivity is deteriorated to thereby form the water-repellent layer composed of the fluorine resin.

Abstract: A membrane electrode assembly for a fuel cell of the present invention includes an electrolyte membrane (100); and a pair of electrode catalyst layers (110) provided on both surfaces of the electrolyte membrane. Furthermore, in the present invention, a plurality of hydrophilic groups exist along a substantially continuous concentration gradient from a surface of one of the electrode catalyst layers opposite to a surface thereof in contact with the electrolyte membrane to a surface of the other electrode catalyst layer opposite to a surface thereof in contact with the electrolyte membrane in a thickness direction of the electrolyte membrane (100) and the electrode catalyst layers (110). This makes it possible to provide a membrane electrode assembly with water management performed not only in the surfaces but also in the entire assembly in the thickness direction.

Abstract: A membrane electrode assembly for a fuel cell of the present invention includes an electrolyte membrane (100); and a pair of electrode catalyst layers (110) provided on both surfaces of the electrolyte membrane. Furthermore, in the present invention, a plurality of hydrophilic groups exist along a substantially continuous concentration gradient from a surface of one of the electrode catalyst layers opposite to a surface thereof in contact with the electrolyte membrane to a surface of the other electrode catalyst layer opposite to a surface thereof in contact with the electrolyte membrane in a thickness direction of the electrolyte membrane (100) and the electrode catalyst layers (110). This makes it possible to provide a membrane electrode assembly with water management performed not only in the surfaces but also in the entire assembly in the thickness direction.