Aluminum alloy sheet for battery lid for forming integrated explosion prevention valve, and method for producing same

Abstract

Provided are: an aluminum alloy sheet for a battery lid that has excellent deformation resistance, moldability, and heat dissipation properties and that makes it possible to form an integrated explosion prevention valve having little variation in operating pressure and excellent cyclic fatigue resistance properties; and a method for producing the aluminum alloy sheet for a battery lid. The aluminum alloy sheet for a battery lid for forming an integrated explosion prevention valve is characterized by having a component composition that includes 0.85-1.50 mass% of Fe, 0.30-0.70 mass% of Mn, 0.002-0.15 mass% of Ti, less than 0.05 mass% of B, and a remainder of Al and impurities, in which the Fe / Mn ratio is controlled so as to be 1.8-3.5, and in which Si, Cu, Mg, and V present as impurities are controlled such that Si is less 0.40 mass%, Cu is less than 0.03 mass%, Mg is less than 0.05 mass%, and V is less than 0.03 mass%. The aluminum alloy sheet for a battery lid for forming an integrated explosion prevention valve is also characterized in that the 0.2% proof stress is 40 MPa or more, the elongation value is 40% or more, the conductivity is 53.0% IACS or more, a recrystallized structure is present, and the elongation value after cold rolling is performed at a rolling reduction ratio of 80% is 6.5% or more. In addition, the average crystal grain size of the recrystallized grains of the recrystallized structure is preferably 15-25 [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.

Images