SEIKO INSTRUMENTS INC.

Alkaline batteries including a positive electrode, a negative electrode, a separator, and an electrolytic solution which are accommodated in a container are provided. The electrolytic solution is a potassium hydroxide aqueous solution having a concentration of 40% to 50%. The negative electrode consists of a gel-like negative electrode mixture containing a negative electrode active material and an alkaline aqueous solution. The alkaline aqueous solution contains potassium hydroxide and sodium hydroxide in a molar ratio range of 89:11 to 96:4. The positive electrode consists of a positive electrode mixture including a positive electrode active material containing silver oxide and manganese dioxide, and a blending ratio of manganese dioxide in the positive electrode mixture is 25% to 50% by mass.

A terminal-equipped button cell of the present invention includes: a cathode can and an anode can having flat cylindrical shapes; a gasket configured to insulate and seal the cathode can and the anode can; and a cathode terminal and an anode terminal fixed to a bottom surface of the cathode can and a bottom surface of the anode can, wherein the bottom surface of the cathode can is curved convexly and outwardly in a thickness direction by 100 μm or less while being integrated with the anode can, and the cathode terminal has a flat cathode connecting part, and the cathode terminal is disposed along a radial direction of the bottom surface of the cathode can, and the cathode connecting part is fixed to the bottom surface by being inclined so as to form a tangent line to the bottom surface at a position other than a center of the bottom surface when viewed in a sectional view following the radial direction and perpendicular to the bottom surface.

An electrochemical cell includes an all-solid-state electrode body in which a positive electrode layer and a negative electrode layer are laminated together through a solid electrolyte and an exterior body having a cavity in which the electrode body is stored. The exterior body has a first case and a second case which sandwich the electrode body and a sealing member that defines the cavity together with the first case and the second case by joining the first case and the second. The thermal expansion coefficients of the electrode body, the first case, the second case, and the sealing member are all 10×10 −6 /° C. or lower.

A battery includes: an electrode body; and an external body which is formed by overlapping a first sheet and a second sheet, and in which the electrode body is accommodated. The external body includes an accommodation portion which is formed in the first sheet, and which accommodates the electrode body therein, and a circumferential edge portion in which the first sheet and the second sheet overlap each other around the accommodation portion. The inside of the accommodation portion is sealed in a state where the first sheet and the second sheet are welded to each other in the circumferential edge portion.