Method for preparing lithium battery aluminum-plastic composite film through coextrusion

Abstract

The invention discloses a method for preparing a lithium battery aluminum-plastic composite film through coextrusion. The lithium battery aluminum-plastic composite film sequentially comprises an explosion-proof protective layer, a protective layer attaching layer, a first grafting composite layer combined with an aluminum foil, an aluminum foil layer, a second grafting composite layer combined with an aluminum foil, a heat sealing layer attaching layer and a heat sealing layer from outside to inside, wherein the protective layer attaching layer and the first grafting composite layer adopt lamination coextrusion and the second grafting composite layer and the heat sealing layer attaching layer adopt lamination coextrusion. The method disclosed by the invention has the advantages that the integral tensile strength and the compressive strength of the composite film are greatly increased; the attaching fastness of the composite film is almost 30% higher than that of like products adopting dry lamination and is up to more than 10N; and therefore, the stamping forming of the composite film is more benefitted and even the domestic aluminum foil can replace the aluminum foil imported from Japan to be applied to stamping.

Description

technical field [0001] The invention relates to the technical field of composite membranes, in particular to a method for co-extruding and compounding aluminum-plastic composite membranes for lithium batteries. Background technique [0002] At present, lithium-ion batteries have fast charging and discharging functions, and are prone to high temperatures during use. The electrolyte at high temperatures is extremely corrosive, and can oxidize and delaminate the composite layer of the packaging film of lithium-ion batteries. The packaging film disclosed in the prior art is bonded with aluminum foil by dry compounding with coating of cured glue. The packaging film produced by this method has low tensile strength, low tensile strength, poor corrosion resistance and insulation, and will Such layers will peel off and delaminate, which will affect the safety and life of lithium-ion batteries. [0003] The currently disclosed technology, the dry composite production process adopted ...

AI Technical Summary

Problems solved by technology

The packaging film disclosed in the prior art is bonded with aluminum foil by dry compounding with coating of cured glue. The packaging film produced by this method has low tensile strength, low tensile strength, poor corrosion resistance and insulation, and will The layers will be peeled off and delaminated, which will affect the safety and life of lithium-ion batteries

[0003] In the currently disclosed technology, the dry composite production process adopted by the battery flexible packaging film, due to the use of solvent-based curing adhesives such as phenolic resin, epoxy resin, and polyurethane adhesive, the organic solvents toluene, ethyl acetate, etc. pollute the ecological environment.

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