Aluminum alloy sheet material for lithium-ion battery and method for producing the same

Patent metadata

Field	Value
Publication number	US-9748527-B2
Application number	US-201314387453-A
Country	US
Kind code	B2
Filing date	Mar 11, 2013
Priority date	Mar 23, 2012
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

An aluminum alloy sheet material for a lithium-ion battery can significantly reduce the number of welding defects (e.g., bead non-uniformity and underfill) that occur during laser welding. The aluminum alloy sheet material includes 0.8 to 1.5 mass % of Mn, 0.6 mass % or less of Si, 0.7 mass % or less of Fe, 0.2 mass % or less of Cu, and 0.2 mass % or less of Zn, with the balance being Al and unavoidable impurities, Al—Mn—Si-based intermetallic compounds having a maximum length of less than 1.0 μm being distributed in a matrix of the aluminum alloy sheet material in a number equal to or larger than 0.25 per μm 2 , and the area ratio of the intermetallic compounds being 3.0% or more when a field of view having an area of 5000 μm 2 is subjected to image analysis.

First claim

The invention claimed is:

1. An aluminum alloy sheet material for a lithium-ion battery comprising 0.8 to 1.5 mass % of Mn, 0.6 mass % or less of Si, 0.7 mass % or less of Fe, 0.2 mass % or less of Cu, and 0.2 mass % or less of Zn, with the balance being Al and unavoidable impurities, Al—Mn—Si-based intermetallic compounds having a maximum length of less than 1.0 μm being distributed in a matrix of the aluminum alloy sheet material in a number equal to or larger than 0.25 per μm 2 , and an area ratio of the intermetallic compounds being 3.0% or more when a field of view having an area of 5000 μm 2 is subjected to image analysis.

2. The aluminum alloy sheet material according to claim 1 , the aluminum alloy sheet material having an electrical conductivity at 25° C. of 45 to 55 IACS %.

3. The aluminum alloy sheet material according to claim 1 , the aluminum alloy sheet material having an average surface crystal grain size (circle equivalent diameter) of 50 μm or less.

4. A method for producing an aluminum alloy sheet material for a lithium-ion battery comprising homogenizing an ingot of an aluminum alloy having the composition according to claim 1 at 400 to 550° C. for 3 to 48 hours, hot-rolling the homogenized ingot at a hot-rolling start temperature of 400 to 550° C., cold-rolling the hot-rolled ingot at a reduction ratio of 70% or more to have a specific thickness, and subjecting the cold-rolled ingot to final annealing in a continuous annealing furnace at a temperature increase rate of 100 to 500° C./s and an annealing temperature of 480 to 550° C.

Assignees

• Uacj Corp

Inventors

• Takiguchi Koichiro

Classifications

• C22F1/00 Primary

  Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working (apparatus for mechanical working of metal B21, B23, B24) · CPC title

• H01M50/119

  Metals · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• Y02E60/122

  Cross-Sectional Technologies · mapped topic