Aluminum alloy plate for battery lid for forming integral explosion-proof valve and method for producing same

Abstract

The invention provide an aluminum alloy plate for a battery lid that is excellent in heat dissipation property, formability and work-softening property, and allows for forming of an integral explosion-proof valve having less variations in working pressures and being excellent in characteristics of resistance to repeated fatigue, and a method for producing the aluminum alloy plate for a battery lid. The aluminum alloy plate for battery lid for forming an integral explosion-proof valve has a component composition containing Fe:1.05-1.50 mass%, Mn:0.15-0.70 mass%, Ti:0.002-0.10 mass% and B: lessthan 0.03 mass%, and the balance Al with impurities; with Fe / Mn ratio controlled to 1.8-7.0; Si controlled to less than 0.40 mass%; Cu controlled to less than 0.03 mass%, Mg controlled to less than 0.05 mass% and V controlled to less than 0.03 mass% as impurities, has a conductivity of 53.0% IACS or more and a value of elongation of 40% or more, has a re-crystallized structure, has a value of (TS95-TS70) of less than -1 MPa when TS70 denotes a tensile strength of the aluminum alloy plate for battery lid for forming an integral explosion-proof valve after being cold-rolled at a reduction of 70%and TS95 denotes the tensile strength after being cold-rolled at a reduction of 95%, and has a value of elongation after being cold-rolled at a reduction of 90% of 5.0% or more. Furthermore, an average crystal particle size of re-crystallized particles of the re-crystallized structure is preferably 15-30 [mu]m.

Description

technical field [0001] The present invention relates to an aluminum alloy plate for a battery cover for forming an integrated explosion-proof valve used in square, cylindrical and other lithium-ion batteries and having a small working pressure deviation. Background technique [0002] In recent years, countries have imposed stricter regulations on automobile exhaust, and the production of electric vehicles, which are environmentally friendly vehicles, is rapidly expanding. Currently, the mainstream of secondary batteries used in electric vehicles is lithium-ion batteries. Lithium-ion battery casings come in various types such as square, cylindrical, and sheet-shaped. In the case of square and cylindrical shapes, aluminum alloy plates that can achieve weight reduction are drawn and processed. Or a shell obtained by thinning and deep drawing processing (also called DI processing). [0003] Thus, as a material for a battery case, development of an aluminum alloy plate having e...

AI Technical Summary

Problems solved by technology

The explosion-proof valve must work reliably, and the valve will automatically break when the internal pressure of the container exceeds the specified pressure, etc.

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