# US 2019/0355990 A1 · Alkaline secondary battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0355990 A1 - Document ID: US20190355990A1 - Status: Published application - Kind: A1 - Application number: 16/482,859 - Filed: 2018-03-12 - Published: 2019-11-21 - Earliest claimed: 2017-03-22 - Assignees: Maxell Holdings, Ltd. - Applicants: Maxell Holdings, Ltd. - Inventors: Yusuke INOUE; Mitsutoshi WATANABE - Web page: https://patentgrep.com/patent/US20190355990A1 ## CPC - H01M 4/34: Silver oxide or hydroxide electrodes - H01M 4/54: of silver - H01M 10/32: Silver accumulators (H01M10/34 takes precedence) - H01M 10/448: {End of discharge regulating measures} - H01M 2004/028: {Positive electrodes} - Y02E 60/10: Energy storage using batteries - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract An alkaline secondary battery disclosed in the present application includes a positive electrode containing a positive electrode active material, a negative electrode, and a separator. The positive electrode active material contains a mixture of a silver oxide and a silver-bismuth complex oxide. A discharge curve is obtained when the battery that is fully charged is discharged with a constant current until a battery voltage drops to 1.0 V. The battery voltage at a point on the discharge curve where x (%) of a total discharge capacity has been discharged from the battery since start of discharge is represented by Vx (V). The discharge curve satisfies V10−V70≤0.08, has a step in the range of 70≤x≤90, and shows that a size of the step represented by V70−V90 is 0.04 or more and 0.15 or less. ## Claims ### Claim 1 An alkaline secondary battery comprising: a positive electrode containing a positive electrode active material; a negative electrode; and a separator, wherein the positive electrode active material contains a mixture of a silver oxide and a silver-bismuth complex oxide, and wherein a discharge curve is obtained when the battery that is fully charged is discharged with a constant current until a battery voltage drops to 1.0 V, the battery voltage at a point on the discharge curve where x (%) of a total discharge capacity has been discharged from the battery since start of discharge is represented by Vx (V), and the discharge curve satisfies V10−V70≤0.08, has a step in a range of 70≤x≤90, and shows that a size of the step represented by V70−V90 is 0.04 or more and 0.15 or less. ### Claim 2 (depends on 1) The alkaline secondary battery according to claim 1, wherein the total discharge capacity is a discharge capacity of the battery obtained under the following charge and discharge conditions: for charging, the battery is subjected to a constant-current and constant-voltage charge, which is a combination of a constant current charge where the battery that has been discharged to 1.0 V is charged with a current value C (mA) at which it takes 4±0.25 hours for the battery voltage to reach 1.85 V from start of charge, and a constant voltage charge where the battery is charged with a voltage of 1.85 V, and the charge of the battery is terminated when the current value is reduced to C/10 (mA); for discharging, the battery is subjected to a constant current discharge where the battery is discharged with a current of C/2 (mA), and the discharge of the battery is terminated when the battery voltage is reduced to 1.0 V. ### Claim 3 (depends on 1) The alkaline secondary battery according to claim 1, wherein there is an inflection point in the range of 70