Bipolar electrode for nickel-hydrogen storage battery and nickel-hydrogen storage battery

Patent metadata

Field	Value
Publication number	US-10693175-B2
Application number	US-201716462762-A
Country	US
Kind code	B2
Filing date	Nov 28, 2017
Priority date	Nov 30, 2016
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

A bipolar electrode includes a metal foil, a first active material layer provided on a front surface of the metal foil, and a second active material layer having a larger area than the first active material layer and provided on a rear surface of the metal foil. The second active material layer includes a low density region disposed in a peripheral portion in plan view as viewed from a thickness direction of the metal foil, and a high density region disposed more inside than the low density region and having a smaller porosity than the low density region.

First claim

The invention claimed is:

1. A bipolar electrode for a nickel-hydrogen storage battery, the bipolar electrode comprising:
a metal foil;
a first active material layer provided on a front surface of the metal foil; and
a second active material layer provided on a rear surface of the metal foil and having a larger area than the first active material layer,
wherein the second active material layer includes
a low density region disposed in a peripheral portion in plan view as viewed from a thickness direction of the metal foil, and
a high density region disposed inward of the low density region and having a smaller porosity than the low density region.

2. The bipolar electrode for a nickel-hydrogen storage battery according to claim 1 , wherein
the high density region is disposed at a position overlapping with at least a part of the first active material layer in plan view as viewed from the thickness direction of the metal foil.

3. The bipolar electrode for a nickel-hydrogen storage battery according to claim 1 , wherein
the high density region has a porosity of from 28 to 40%.

4. The bipolar electrode for a nickel-hydrogen storage battery according to claim 1 , wherein
the low density region has a porosity of from 56 to 63%.

5. The bipolar electrode for a nickel-hydrogen storage battery according to claim 1 , wherein
a thickness of the low density region is larger than a thickness of the high density region.

6. The bipolar electrode for a nickel-hydrogen storage battery according to claim 5 , wherein
an intermediate region having a larger thickness as being closer to the low density region is interposed between the low density region and the high density region.

7. The bipolar electrode for a nickel-hydrogen storage battery according to claim 1 , wherein
the first active material layer is a positive electrode active material layer and the second active material layer is a negative electrode active material layer.

8. A nickel-hydrogen storage battery comprising:
an electrode assembly in which a plurality of electrodes are stacked with separators interposed therebetween,
wherein the electrode assembly includes
terminal electrodes disposed at both ends in a stacking direction, and
the bipolar electrode for a nickel-hydrogen storage battery according to claim 1 disposed between the terminal electrodes.

Assignees

• Toyota Jidoshokki Kk

Inventors

• Sugimoto Yuki
• MINAGATA Atsushi

Classifications

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M50/46

  Separators, membranes or diaphragms characterised by their combination with electrodes · CPC title

• H01M10/30

  Nickel accumulators (H01M10/34 takes precedence) · CPC title

• H01M4/32

  Nickel oxide or hydroxide electrodes · CPC title

• H01M4/26

  Processes of manufacture · CPC title