Steel foil for power storage device container, power storage device container, power storage device, and manufacturing method of steel foil for power storage device container

Patent metadata

Field	Value
Publication number	US-10418601-B2
Application number	US-201515327227-A
Country	US
Kind code	B2
Filing date	Jul 22, 2015
Priority date	Jul 22, 2014
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

A steel foil for a power storage device container includes a rolled steel foil which has a thickness of 200 μm or less, a diffusion alloy layer which is formed on a surface layer of the rolled steel foil and contains Ni and Fe, and a chromium-based surface treatment layer which is formed on the diffusion alloy layer. The <111> polar density in a reverse pole figure of the diffusion alloy layer in a rolling direction is 2.0 to 6.0, and the aspect ratio of crystal in a surface of the diffusion alloy layer is 1.0 to 5.0.

First claim

What is claimed is:

1. A steel foil for a power storage device container comprising:
a rolled steel foil which has a thickness of 200 μm or less;
a diffusion alloy layer which is formed on a surface layer of the rolled steel foil and contains Ni and Fe; and
a chromium-based surface treatment layer which is formed on the diffusion alloy layer,
wherein <111> polar density in a reverse pole figure of the diffusion alloy layer in a rolling direction is 2.0 to 6.0, and
wherein an aspect ratio of a crystal in a surface of the diffusion alloy layer is 1.0 to 5.0.

2. The steel foil for a power storage device container according to claim 1 , wherein
I FeNi3 /I Ni which is a ratio between a intensity I Ni of a diffraction peak of Ni and a intensity I FeNi3 of a diffraction peak of FeNi 3 which are obtained by measuring X-ray diffraction on the diffusion alloy layer is equal to or higher than 5.0 or the diffraction peak of Ni is not detected.

3. The steel foil for a power storage device container according to claim 1 , further comprising:
a polyolefin-based resin layer which is formed on a surface of the chromium-based surface treatment layer.

4. A power storage device container which includes the steel foil for a power storage device container according to claim 3 .

5. A power storage device comprising:
the power storage device container according to claim 4 .

6. A manufacturing method of a steel foil for a power storage device container, the method comprising:
a nickel-plating process of performing a nickel plating on a steel sheet so as to form a Ni-plated layer on the steel sheet, and obtaining a Ni-plated steel sheet;
an annealing process of annealing the Ni-plated steel sheet so that Fe in the steel sheet and Ni in the Ni-plated layer are mutually diffused;
a cold-rolling process of performing a cold rolling on the Ni-plated steel sheet at cumulative rolling reduction of 70% or higher, and obtaining a steel foil;
a recrystallization annealing process of annealing the steel foil at 750° C. to 1100° C. for 4 to 120 seconds under an annealing condition in which Tc and Ta satisfy the following expression (1) in a case of 750≤Ta≤800 and satisfy the following expression (2) in a case of Ta>800, wherein an annealing time is defined as Tc in an unit second, and an annealing temperature is defined as Ta in an unit of ° C.; and
a chromium-based surface treatment process of performing a chromium-based surface treatment on the steel foil;
Tc≥ 13−0.1×( Ta− 750)  (1)

Tc≥ 8−(4/300)×( Ta− 800)  (2).

7. The manufacturing method of a steel foil for a power storage device container, according to claim 6 , wherein
in the recrystallization annealing process, the Tc and the Ta satisfy the following expression (3) in a case of 750≤Ta≤800, and satisfy the following expression (4) in a case of Ta>800,
Tc≥ 16−0.1×( Ta− 750)  (3)

Tc≥ 11−0.02×( Ta− 800)  (4).

8. The manufacturing method of a steel foil for a power storage device container, according to claim 6 , further comprising:
a polyolefin resin layer forming process of forming a polyolefin resin layer on a surface of the steel foil after the chromium-based surface treatment process by a thermal laminate method.

9. The steel foil for a power storage device container according to claim 2 , further comprising:
a polyolefin-based resin layer which is formed on a surface of the chromium-based surface treatment layer.

10. A power storage device container which includes the steel foil for a power storage device container according to claim 9 .

11. A power storage device comprising:
the power storage device container according to claim 10 .

12. The manufacturing method of a steel foil for a power storage device container, according to claim 7 , further comprising:
a polyolefin resin layer forming process of forming a polyolefin resin layer on a surface of the steel foil after the chromium-based surface treatment process by a thermal laminate method.

Assignees

• Nippon Steel Corp
• Nippon Steel Chemical & Mat Co Ltd

Inventors

• Ibaragi Masaharu
• Nose Koichi
• Ishizuka Kiyokazu
• Goto Yasuto
• Nagasaki Shuji
• Unno Hiroto

Classifications

• C23C10/28 Primary

  using solids, e.g. powders, pastes · CPC title

• H01G11/78

  Cases; Housings; Encapsulations; Mountings · CPC title

• C23C28/00

  Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D · CPC title

• B32B15/01 Primary

  all layers being exclusively metallic {(making layered metal workpieces by pressure cladding B23K20/22; making coatings with a metallic material characterised by its composition C23C30/00)} · CPC title

• C25D7/0614

  Strips or foils · CPC title