Patent attributes
A metal-resin composite having high gas sealing properties is provided. An aluminum alloy structure having a shape surrounding the copper 63 is firstly formed, and the attached aluminum alloy is made closely contact with the copper electrode 63 and further made engaged into the copper electrode 63 by pressing or forging. It is then machined into a predetermined shape so as to prepare the copper alloy 63 attached with an aluminum alloy part 61a. Subsequently, the surface treatment of the NMT or NMT 2 is given to three members of an aluminum electrode 62, the copper electrode 63 attached with the aluminum alloy part 61a and an aluminum alloy lid 61. These three members are inserted into an injection mold, and a thermoplastic resin composition 64 of PPS resin is injected. The lithium-ion battery lid 60 having a structure as shown in FIG. 11 is thus obtained.