阅读说明：本技术 一种石墨烯复合软包装膜及锂离子电池 (Graphene composite flexible packaging film and lithium ion battery ) 是由 何大平 杨金龙 钱伟 于 2020-06-13 设计创作，主要内容包括：一种石墨烯复合软包装膜。所述石墨烯复合软包装膜包括依次叠设的第一聚合物层、第一胶粘层、石墨烯薄膜层、第二胶粘层以及第二聚合物层,所述石墨烯薄膜层的底部表面相对所述第一聚合物层设置并且通过第一胶粘层与所述第一聚合物层粘结；所述石墨烯薄膜层的顶部表面相对所述第二聚合物层设置并且通过第二胶粘层与所述第二聚合物层粘结。本发明提供的石墨烯薄膜能够电池体系中非常稳定存在且耐电解液腐蚀,具备优异的阻隔性能和耐腐蚀性能。此外能够很好的解决散热问题,提高电池的寿命和安全性能。本发明还提供了一种包含如上石墨烯复合软包装膜的锂离子电池。(A graphene composite flexible packaging film. The graphene composite flexible packaging film comprises a first polymer layer, a first adhesive layer, a graphene film layer, a second adhesive layer and a second polymer layer which are sequentially stacked, wherein the bottom surface of the graphene film layer is arranged opposite to the first polymer layer and is bonded with the first polymer layer through the first adhesive layer; the top surface of the graphene film layer is disposed opposite the second polymer layer and is bonded to the second polymer layer by a second adhesive layer. The graphene film provided by the invention can exist in a battery system very stably and resist electrolyte corrosion, and has excellent barrier property and corrosion resistance. In addition, the heat dissipation problem can be well solved, and the service life and the safety performance of the battery are improved. The invention also provides a lithium ion battery containing the graphene composite flexible packaging film.)

1. The utility model provides a compound flexible packaging film of graphite alkene which characterized in that: the graphene film comprises a first polymer layer, a first adhesive layer, a graphene film layer, a second adhesive layer and a second polymer layer which are sequentially stacked, wherein the bottom surface of the graphene film layer is arranged opposite to the first polymer layer and is bonded with the first polymer layer through the first adhesive layer; the top surface of the graphene film layer is disposed opposite the second polymer layer and is bonded to the second polymer layer by a second adhesive layer.

2. The graphene composite flexible packaging film of claim 1, wherein: the material of the first polymer layer is at least one of polyester fiber, polyamide fiber, polyimide, polyethylene, polypropylene, polyacrylonitrile and polyethylene/polypropylene composite material.

3. The graphene composite flexible packaging film of claim 2, wherein: the first polymer layer is a polyamide fiber.

4. The graphene composite flexible packaging film of claim 1, wherein: the material of the second polymer layer is at least one of polyester fiber, polyamide fiber, polyimide, polyacrylonitrile, polyethylene, polypropylene and polyethylene/polypropylene composite material.

5. The graphene composite flexible packaging film according to claim 4, wherein: the material of the second polymer layer is polypropylene.

6. The graphene composite flexible packaging film of claim 1, wherein: the first adhesive layer and the second adhesive layer are made of at least one of aliphatic polyether urethane adhesive, thermoplastic polyimide adhesive, polyvinyl acetal adhesive, polyurethane adhesive, epoxy resin adhesive or acidic polypropylene.

7. The graphene composite flexible packaging film according to claim 6, wherein: the first adhesive layer and the second adhesive layer are polyurethane adhesives.

8. The graphene composite flexible packaging film of claim 1, wherein: the thickness of the graphene film layer is between 4 and 100 mu m.

9. A lithium ion battery comprising the graphene composite flexible packaging film according to any one of claims 1 to 8.

Technical Field

The invention relates to a lithium ion battery flexible packaging film material, in particular to a graphene composite flexible packaging film for a lithium ion battery. The invention also provides a lithium ion battery containing the graphene composite flexible packaging film.

Background

The soft package battery, especially the soft package lithium ion battery, has the advantages of large energy density, good safety performance, flexible appearance and the like, is widely applied to the fields of 3C digital products, electric tools and the like, and occupies a very important position in battery products. Most soft package lithium ion batteries on the market at present adopt the plastic-aluminum membrane to encapsulate, and the plastic-aluminum membrane quality is light, the leakproofness is good, and the deflection is big, can prevent the battery explosion, therefore the demand to the plastic-aluminum membrane is very big on the market at present.

In general, the electrolyte in the battery is highly corrosive, and particularly a soft packaging film with high stability is required under the extreme voltage conditions of the battery. And the aluminum belongs to active metal, when the inner layer of the aluminum-plastic film is damaged, the aluminum foil of the middle layer contacts the electrolyte in the battery to form a primary battery, the primary battery is easily corroded by the electrolyte to influence the barrier property of the primary battery, and the aluminum and the active material easily form aluminum alloy at a low potential. Such as aluminum lithium alloys in soft-pack lithium ion batteries, which deplete the active lithium material in the battery, resulting in a diminished, or even a failed, battery capacity.

On the other hand, the battery product has the phenomenon of generating heat and scalding in the processes of quick charging, quick discharging and long-time use, and the existing soft package aluminum-plastic film has high heat resistance but cannot effectively dissipate heat, so that the battery has certain potential safety hazard in the use process.

Disclosure of Invention

In view of the above, it is necessary to provide a graphene composite flexible packaging film with good heat dissipation and corrosion resistance for an outer packaging film of a lithium ion battery to solve the above problems.

The graphene composite flexible packaging film comprises a first polymer layer, a first adhesive layer, a graphene film layer, a second adhesive layer and a second polymer layer which are sequentially stacked, wherein the bottom surface of the graphene film layer is arranged opposite to the first polymer layer and is bonded with the first polymer layer through the first adhesive layer; the top surface of the graphene film layer is disposed opposite the second polymer layer and is bonded to the second polymer layer by a second adhesive layer.

Preferably, the material of the first polymer layer is at least one of polyester fiber, polyamide fiber, polyimide, polyethylene, polypropylene, polyacrylonitrile and polyethylene/polypropylene composite material.

Preferably, the first polymer layer is polyamide fiber.

Preferably, the material of the second polymer layer is at least one of polyester fiber, polyamide fiber, polyimide, polyacrylonitrile, polyethylene, polypropylene and polyethylene/polypropylene composite material.

Preferably, the material of the second polymer layer is polypropylene.

Preferably, the material of the first adhesive layer and the second adhesive layer is at least one of aliphatic polyether urethane adhesive, thermoplastic polyimide adhesive, polyvinyl acetal adhesive, polyurethane adhesive, epoxy resin adhesive or acidic polypropylene.

Preferably, the first adhesive layer and the second adhesive layer are polyurethane adhesives.

Preferably, the thickness of the graphene thin film layer is between 4 and 100 μm.

A lithium ion battery comprises the graphene composite flexible packaging film.

The graphene composite flexible packaging film provided by the invention is a composite film obtained by adopting a compact graphene film as an intermediate layer, and the graphene film can exist in a battery system very stably and is resistant to electrolyte corrosion, and has excellent barrier property and corrosion resistance. In addition, the graphene composite flexible packaging film is light and thin in texture and can well replace an aluminum plastic film.

On the other hand, the graphene material has high heat radiation performance and high heat conduction performance; the graphene composite flexible packaging film for the outer packaging film of the lithium ion battery can effectively solve the problem of heat dissipation, and the service life and the safety performance of the battery are improved.

Drawings

Fig. 1 is a schematic structural diagram of a graphene composite flexible packaging film provided by the invention.

Detailed Description

In order to make the technical solutions of the present invention better understood by those skilled in the art, the following detailed description of the present invention is provided with reference to the accompanying drawings.

Please refer to fig. 1, wherein fig. 1 is a schematic structural diagram of a graphene composite flexible packaging film provided by the present invention.

The graphene composite flexible packaging film 100 provided by the invention comprises a first polymer layer 10, a first adhesive layer 20, a graphene film layer 30, a second adhesive layer 40 and a second polymer layer 50 which are sequentially stacked from the bottom. The first adhesive layer 20 is disposed between the first polymer 10 and the graphene film layer 30; the second adhesive layer 40 is disposed between the graphene film layer 30 and the second polymer layer 50.

The first polymer layer 10 is a bottom layer of the graphene composite flexible packaging film 100, and may be at least one of polyester fiber, polyamide fiber, polyimide, polyacrylonitrile, polyethylene, polypropylene, and polyethylene/polypropylene composite material, and preferably, the first polymer layer 10 is polypropylene. The first polymer layer 10 is located inside the lithium ion battery in normal use and has a thickness of between 4 and 100 μm.

The graphene film 30 is located in the middle of the graphene composite flexible packaging film 100. The top surface of the graphene film 30 is disposed toward the second polymer layer 20; the bottom surface of the graphene thin film 30 is disposed toward the first polymer layer 10. The graphene layer is a flexible graphene film with high compactness and good mechanical properties. The thickness of the graphene film is between 4 and 100 mu m.

The first adhesive layer 20 is disposed between the first polymer layer 10 and the graphene film layer 30, and bonds and fixes the bottom surfaces of the first polymer layer 10 and the graphene film layer 30. The first adhesive layer 10 may be at least one of an aliphatic polyether urethane adhesive, a thermoplastic polyimide adhesive, a polyvinyl acetal adhesive, a polyurethane adhesive, an epoxy resin adhesive, and an acidic polypropylene, and is preferably a polyurethane adhesive.

The second polymer layer 50 is a top layer of the graphene composite flexible packaging film 100, and may be at least one of polyester fiber, polyamide fiber, polyimide, polyethylene, polypropylene, polyacrylonitrile, and polyethylene/polypropylene composite material. Preferably, the material of the first polymer layer 10 is polyamide fibers. The second polymer layer 50 is located outside the lithium ion battery under normal use conditions, and the thickness of the second polymer layer 50 is between 4 and 100 μm. Preferably, the thickness of the second polymer layer 50 is between 10-30 μm.

The second adhesive layer 40 is disposed between the second polymer layer 50 and the graphene film layer 30, and bonds and fixes the top surfaces of the second polymer layer 50 and the graphene film layer 30.

The first polymer layer 10, the first adhesive layer 20, the graphene film layer 30, the second adhesive layer 40 and the second polymer layer 50 are bonded together by direct pressing or hot pressing, so as to prepare the graphene composite flexible packaging film 100. The graphene composite flexible packaging film 100 can be used for lithium ion batteries, and can also be used as a packaging material in other fields.

A packaging film of the lithium ion battery is the graphene composite flexible packaging film 100.