Sony Corporation

Kuniyasu Oya

Kenta Yamamoto

Osamu Takahashi

Kazuo Honda

Kazuhiro Hashimoto

Naoko Yamakawa

Yoshinari Ichinose

Shinichi Ando

A size AA alkaline battery includes an anode principally composed of zinc functioning as an active material, a cathode principally composed of manganese dioxide or nickel oxyhydroxide functioning as an active material, a separator composed of a nonwoven fabric, an electrolyte composed of an aqueous solution of potassium hydroxide, and zinc oxide.

Size AA alkaline battery

The present invention provides a nickel-zinc battery of an inside-out structure, that is, a battery comprising a positive electrode containing beta-type nickel oxyhydroxide and a negative electrode containing zinc and having a similar structure to an alkali manganese battery, in which the beta-type nickel oxyhydroxide consists of substantially spherical particles, mean particle size of which is within a range from 19 &#x3bc;m to a maximum of 40 &#x3bc;m, the bulk density of which is within a range from 1.6 g/cmto a maximum of 2.2 g/cm, tap density of which is within a range from 2.2 g/cmto a maximum of 2.7 g/cm, specific surface area which based on BET method is within a range from 3 m/g to a maximum of 50 m/g, and the positive electrode of the nickel zinc battery contains graphite powder, where the weight ratio of graphite powder against a total weight of the positive electrode is defined within a range from 4% to a maximum of 8%.

Positive electrode material and nickel-zinc battery

The present invention provides a nickel-zinc battery of an inside-out structure, that is, a battery comprising a positive electrode containing beta-type nickel oxyhydroxide and a negative electrode containing zinc and having a similar structure to an alkali manganese battery, in which the beta-type nickel oxyhydroxide consists of substantially spherical particles, mean particle size of which is within a range from 19 &mgr;m to a maximum of 40 &mgr;m, the bulk density of which is within a range from 1.6 g/cm to a maximum of 2.2 g/cm , tap density of which is within a range from 2.2 g/cm to a maximum of 2.7 g/cm , specific surface area which based on BET method is within a range from 3 m /g to a maximum of 50 m /g, and the positive electrode of the nickel zinc battery contains graphite powder, where the weight ratio of graphite powder against a total weight of the positive electrode is defined within a range from 4% to a maximum of 8%.

A battery in which an electrolytic solution may be prevented from leakage. Within a battery case in the form of a bottomed tube, a positive electrode, a negative electrode and an electrolyte are arranged. An opening in the battery case is sealed by a battery lid having a degassing hole, which degassing hole is covered by a sheathing member.

Battery with a sheathing member to prevent leakage of electrolytic solution

A battery including a sealing member 10 for sealing an opening 7 of a battery housing 1, a current collecting pin 5 press-fitted in a through hole 11 formed through the sealing member 10, and a reinforcing member 20 for reinforcing the sealing member 10. The reinforcing member 20 is constituted of a thick-walled portion 21 for covering an outer circumferential surface of a cylindrical portion 12 of the sealing member 10 forming the through hole 11 and a disk portion 22 extending radially outwardly from the thick-walled portion 21. A space 8 is defined between the sealing member 10 and the reinforcing member 20, and a thin-walled portion 13 for preventing an increase in internal pressure in the battery housing 1 is formed in the sealing member 10 at a position opposed to the space 8. The sealing member 10 is reinforced by the thick-walled portion 21 to thereby prevent generation of cracks in the sealing member 10 and electrolyte leakage accompanied thereby. Further, when the internal pressure increases, the thin walled portion 13 is reliably broken to suppress the increase in the internal pressure.

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Fukushima, Japan

Kuniyasu Oya