Ngk Insulators, Inc.

Takeshi Yagi

Kenshin Kitoh

Junki Matsuya

Yuichi Gonda

An electrode-separator assembly is provided that can drastically facilitate assembly of a LDH separator-equipped nickel-zinc battery without the work, structure, or components for the complete separation of a positive-electrode chamber from a negative-electrode chamber. The electrode-separator assembly includes a positive-electrode plate, a negative-electrode plate, a layered double hydroxide (LDH) separator for separation of the positive-electrode plate from the negative-electrode plate, and a resin frame having an opening to which the LDH separator and the positive-electrode plate are fitted or joined. The positive-electrode plate has a smaller face than the negative-electrode plate. The negative-electrode plate has a clearance area that does not overlap with the positive-electrode plate over a predetermined width from the outer peripheral edge of the negative-electrode plate. The peripheral end faces of the LDH separator, and a segment of the separator adjacent to the positive-electrode plate and corresponding to the clearance area, are covered with the resin frame.

Electrode/separator layered body and nickel zinc battery equipped therewith

There is provided a secondary zinc battery including: a unit cell including; a positive-electrode plate including a positive-electrode active material layer and a positive-electrode collector; a negative-electrode plate including a negative-electrode active material layer containing zinc and a negative-electrode collector; a layered double hydroxide (LDH) separator covering or wrapping around the entire negative-electrode active material layer; and an electrolytic solution. The positive-electrode collector has a positive-electrode collector tab extending from one edge of the positive-electrode active material layer, and the negative-electrode collector has a negative-electrode collector tab extending from the opposite edge of the negative-electrode active material layer and beyond a vertical edge of the LDH separator. The unit cell can thereby collects electricity from the positive-electrode collector tab and the negative-electrode collector tab. The LDH separator has at least two continuous closed edges, provided that an edge, adjacent to the negative-electrode collector tab, of the LDH separator is open.

Zinc secondary battery

There is provided a secondary zinc battery including: (a) at least one unit cell including; a positive electrode; a negative-electrode structure including a negative-electrode active material layer containing at least one selected from the group consisting of elemental zinc, zinc oxide, zinc alloys, and zinc compounds; a LDH separator including a porous substrate composed of a polymeric material and layered double hydroxide (LDH); and an electrolytic solution; and (b) a pressuring unit compacting the unit cell to bring the negative-electrode structure in close contact with the LDH separator. Pores of the porous substrate are filled with the LDH such that the LDH separator is hydroxide-ion-conductive and gas-impermeable. The LDH separator separates the positive electrode from the negative-electrode active material layer.

Provided is a positive electrode structure for a secondary battery. This positive electrode structure includes: a positive electrode current collector composed of a tabular nickel foam and having a tabular coated portion and an uncoated portion extending from an outer peripheral portion of the coated portion; and a positive electrode active material containing nickel hydroxide and/or nickel oxyhydroxide incorporated into the coated portion of the positive electrode current collector. The positive electrode active material is not present in the uncoated portion of the positive electrode current collector, and the nickel foam constituting the uncoated portion is compressed so as to have a thickness of 0.10 times or more and less than 0.8 times a thickness of the nickel foam constituting the coated portion.

Positive electrode structure for secondary battery

Provided is a positive electrode structure including: a positive electrode current collector composed of a tabular nickel foam and having a tabular coated portion and an uncoated portion extending from an outer peripheral portion of the coated portion; a positive electrode active material containing nickel hydroxide and/or nickel oxyhydroxide incorporated into the coated portion of the positive electrode current collector; and a nonwoven fabric made of a polymer material and covering the coated portion of the positive electrode current collector from both sides. The positive electrode active material is not present in the uncoated portion of the positive electrode current collector. The nonwoven fabric covers an entirety of the coated portion and extends from the outer peripheral portion of the coated portion to form a surplus region, and the surplus region is sealed so as to close all around the outer peripheral portion of the coated portion.

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Nagoya, Japan

Takeshi Yagi