CN218660868U

CN218660868U - Lithium battery aluminum plastic film with multilayer structure

Info

Publication number: CN218660868U
Application number: CN202223085727.3U
Authority: CN
Inventors: 付有虎; 董青山
Original assignee: Kunshan Zhixin Tiancheng Electronic Material Co ltd
Current assignee: Kunshan Zhixin Tiancheng Electronic Material Co ltd
Priority date: 2022-11-16
Filing date: 2022-11-16
Publication date: 2023-03-21
Anticipated expiration: 2032-11-16

Abstract

The utility model relates to a multilayer structure's lithium cell plastic-aluminum membrane includes strengthening layer, outer protective layer, aluminium foil layer and heat-seal layer in proper order from outer to interior, has set gradually thermal contraction rete and aluminized aluminium rete from outer to interior between outer protective layer and the aluminium foil layer, and aluminized aluminium rete and PP drench the rete from outer to interior having set gradually between aluminium foil layer and the heat-seal layer, adjacent strengthening layer, outer protective layer, thermal contraction rete, aluminized aluminium rete, aluminium foil layer, aluminized aluminium rete, PP drenches and bonds together through the adhesive between rete and the heat-seal layer. The utility model has the advantages that the inner layer and the outer layer of the aluminum foil layer are both provided with the aluminum plating film layer, so that the barrier property and the sealing property can be obviously improved; the risk of cracks on the aluminum foil layer can be reduced through the heat shrinkable film layer.

Description

Lithium battery aluminum plastic film with multilayer structure

Technical Field

The utility model relates to a relevant technical field of plastic-aluminum membrane especially relates to a multilayer structure's lithium cell plastic-aluminum membrane.

Background

In recent years, with the development of miniaturization, thinning, large capacity and high power charging and discharging of lithium batteries, aluminum plastic films which are light, thin, flexible and high in mechanical strength become one of the important points of research and development in related fields. And cladding the bare cell by adopting an aluminum-plastic composite film, and performing hot-press packaging on the two layers of aluminum-plastic composite films on the top surface and the side surface.

Through the massive search, the publication number of the prior art is CN208400892U, and the prior art discloses a coating film structure for a lithium battery, which comprises a nylon film, a polypropylene carbon fiber composite film, an aluminum foil, a polypropylene cast film, a polytetrafluoroethylene activated film, an activated layer, a first thermocementing layer, a first dry cementing layer, a second dry cementing layer and a second thermocementing layer, wherein the nylon film is the outermost layer of the coating film and is a reinforced layer, the polypropylene carbon fiber composite film is a reinforced layer, the aluminum foil is a soft metal aluminum layer, the polypropylene cast film is a bonding layer, the polytetrafluoroethylene activated film is the innermost layer of the coating film and is directly contacted with electrolyte, the coating film structure has good electrical insulation, high temperature resistance and corrosion resistance, the activated layer is arranged on one surface of the polytetrafluoroethylene activated film, which is close to the polypropylene cast film, the activated layer is subjected to activation treatment, the second thermocementing layer is coated between the nylon film and the polypropylene carbon fiber composite film for bonding, and the first thermocementing layer is coated between the polytetrafluoroethylene activated film and the polypropylene cast film for bonding.

In summary, if the aluminum foil layer of the conventional aluminum plastic film for lithium battery is too thin, the barrier property and the sealing property are poor when the thickness is generally less than 20 um.

In view of the above-mentioned defects, the present designer is actively making research and innovation to create a multi-layer aluminum plastic film for lithium battery, so that the film has more industrial utility value.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model aims at providing a multilayer structure's lithium cell plastic-aluminum membrane.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the lithium battery aluminum plastic film with the multilayer structure sequentially comprises a strengthening layer, an outer protective layer, an aluminum foil layer and a heat sealing layer from outside to inside, wherein a heat shrinkable film layer and an aluminum plated film layer are sequentially arranged between the outer protective layer and the aluminum foil layer from outside to inside, the aluminum plated film layer and a PP (polypropylene) coated film layer are sequentially arranged between the aluminum foil layer and the heat sealing layer from outside to inside, the adjacent strengthening layer, the outer protective layer, the heat shrinkable film layer, the aluminum plated film layer, the aluminum foil layer, the aluminum plated film layer, the PP coated film layer and the heat sealing layer are bonded together through an adhesive, the heat shrinkable film layer sequentially comprises a polyethylene micro layer, an ethylene-vinyl acetate copolymer micro layer, a polyvinylidene chloride micro layer, an ethylene-vinyl acetate copolymer micro layer and a polyethylene micro layer from outside to inside, and the aluminum plated film layer sequentially comprises a base material layer, an aluminum plated layer and a corona layer from outside to inside.

As a further improvement of the utility model, the strengthening layer comprises a nylon film layer and a polypropylene carbon fiber composite film layer from outside to inside in sequence.

As a further improvement, the thickness of the nylon film layer is 10-20 um, and the thickness of the polypropylene carbon fiber composite film layer is 30-40 um.

As a further improvement of the utility model, the outer protective layer comprises a PET curtain coating film outer protective layer and a PA curtain coating film outer protective layer from outside to inside in proper order.

As a further improvement of the utility model, the thickness of the PET casting film outer protective layer is 15-30um, and the thickness of the PA casting film outer protective layer is 10-30 um.

As a further improvement of the utility model, the thickness of the aluminum foil layer is 10-40um, the thickness of the PP coating layer is 10-30 um, and the heat sealing layer is a CPP casting film heat sealing layer and the thickness is 20-40 um.

As a further improvement of the utility model, the thickness of the thermal contraction film layer is 20-60 um, and the thickness of the polyethylene microlayer, the ethylene-vinyl acetate copolymer microlayer and the polyvinylidene chloride microlayer are the same.

As a further improvement, the thickness of the aluminizing film layer is 10-20 um, and the substrate layer is a BOPP evaporation coating substrate layer or a BOPET evaporation coating substrate layer.

Borrow by above-mentioned scheme, the utility model discloses at least, have following advantage:

the utility model has the advantages that the inner layer and the outer layer of the aluminum foil layer are both provided with the aluminum plating film layer, so that the barrier property and the sealing property can be obviously improved; the risk of cracks on the aluminum foil layer can be reduced through the heat shrinkable film layer.

The above description is only an outline of the technical solution of the present invention, and in order to make the technical means of the present invention more clearly understood and to be implemented in accordance with the content of the specification, the following detailed description will be given of preferred embodiments of the present invention in conjunction with the accompanying drawings.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a lithium battery aluminum plastic film with a multilayer structure according to the present invention;

FIG. 2 is a schematic diagram of the structure of the enhancement layer of FIG. 1;

FIG. 3 is a schematic structural diagram of the outer protective layer of FIG. 1;

FIG. 4 is a schematic view of the construction of the heat shrinkable film layer of FIG. 1;

fig. 5 is a schematic structural view of the aluminum plating film layer in fig. 1.

In the drawings, the meanings of the reference numerals are as follows.

1 reinforcing layer 2 outer protective layer

3 heat shrinkable film layer 4 aluminized film layer

5 aluminium foil layer 6PP drenches rete

7 Heat-sealing layer 11 Nylon film layer

Outer protective layer of 12 polypropylene carbon fiber composite film layer 21PET casting film

22PA cast film outer protective layer 31 polyethylene microlayer

32 ethylene-vinyl acetate copolymer microlayers 33 polyvinylidene chloride microlayers

41 substrate layer 42 aluminized layer

43 Corona layer

Detailed Description

The following detailed description of the embodiments of the present invention is made with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

In order to make the technical solution of the present invention better understood, the technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiment of the present invention, all other embodiments obtained by the person skilled in the art without creative work belong to the protection scope of the present invention.

Examples

As shown in figures 1 to 5 of the drawings,

the lithium battery aluminum plastic film with the multilayer structure sequentially comprises a strengthening layer 1, an outer protective layer 2, an aluminum foil layer 5 and a heat sealing layer 7 from outside to inside, a heat shrinkage film layer 3 and an aluminum plating film layer 4 are sequentially arranged between the outer protective layer 2 and the aluminum foil layer 5 from outside to inside, an aluminum plating film layer 4 and a PP (polypropylene) coating layer 6 are sequentially arranged between the aluminum foil layer 5 and the heat sealing layer 7 from outside to inside, and the adjacent strengthening layer 1, the outer protective layer 2, the heat shrinkage film layer 3, the aluminum plating film layer 4, the aluminum foil layer 5, the aluminum plating film layer 4, the PP coating film layer 6 and the heat sealing layer 7 are bonded together through an adhesive. The adhesive may be a polyurethane adhesive, an epoxy adhesive, or the like.

The strengthening layer 1 comprises a nylon film layer 11 and a polypropylene carbon fiber composite film layer 12 from outside to inside in sequence. The thickness of the nylon film layer 11 is 10-20 um, and the thickness of the polypropylene carbon fiber composite film layer 12 is 30-40 um.

The outer protective layer 2 includes a PET casting film outer protective layer 21 and a PA casting film outer protective layer 22 in this order from the outside to the inside. The thickness of the PET casting film outer protective layer 21 is 15-30um, and the thickness of the PA casting film outer protective layer 22 is 10-30 um.

The heat shrinkable film layer 3 comprises a polyethylene micro-layer 31, an ethylene-vinyl acetate copolymer micro-layer 32, a polyvinylidene chloride micro-layer 33, an ethylene-vinyl acetate copolymer micro-layer 32 and a polyethylene micro-layer 31 in sequence from outside to inside. The thickness of the heat shrinkable film layer 3 is 20-60 um, and the thickness of the polyethylene microlayer 31, the thickness of the ethylene-vinyl acetate copolymer microlayer 32 and the thickness of the polyvinylidene chloride microlayer 33 are the same. The heat shrinkable film layer 3 adopts a multi-layer structure, and forms a structure similar to a co-extruded film together, when the lithium battery is heated, the heat shrinkable film layer 3 of the multi-layer structure thermally shrinks and generates a shrinking force, and the stress from the aluminum plastic film can be counteracted to a certain degree, so that bubbling of the aluminum plastic film is inhibited.

The aluminum plating film layer 4 includes a base material layer 41, an aluminum plating layer 42, and a corona layer 43 in this order from the outside to the inside. The thickness of aluminized film layer 4 is 10 ~ 20um, and substrate layer 41 is BOPP evaporation coating by vaporization substrate layer or BOPET evaporation coating by vaporization substrate layer. The surface of the base material layer 41 for vapor deposition of metal is formed into a corona layer 43 by corona, and the aluminum plating layer 42 is vapor deposited on the corona layer 43. The barrier structure is formed by the aluminum-plated film layer 4 and the aluminum foil layer 5, so that the barrier property and the sealing property of the aluminum plastic film with the single aluminum foil layer 5 structure can be improved to a certain degree. The substrate layer 41 located on the outer layer may be a BOPP evaporation substrate layer, and the substrate layer 41 located on the inner layer may be a BOPET evaporation substrate layer.

The thickness of the aluminum foil layer 5 is 10-40um, the thickness of the PP film coating layer 6 is 10-30 um, and the heat sealing layer 7 is a CPP cast film heat sealing layer and the thickness is 20-40 um.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly referring to the number of technical features being grined. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted", "connected" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected: either mechanically or electrically: the terms may be directly connected or indirectly connected through an intermediate member, or may be a communication between two elements.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. The lithium battery aluminum plastic film with the multilayer structure comprises a strengthening layer (1), an outer protection layer (2), an aluminum foil layer (5) and a heat sealing layer (7) in sequence from outside to inside, and is characterized in that a heat shrinkage film layer (3) and an aluminum plating film layer (4) are sequentially arranged between the outer protection layer (2) and the aluminum foil layer (5) from outside to inside, the aluminum plating film layer (4) and a PP (polypropylene) lamination layer (6) are sequentially arranged between the aluminum foil layer (5) and the heat sealing layer (7) from outside to inside, the strengthening layer (1), the outer protection layer (2), the heat shrinkage film layer (3), the aluminum plating film layer (4), the aluminum foil layer (5), the aluminum plating film layer (4), the PP lamination layer (6) and the heat sealing layer (7) are bonded together through an adhesive, the heat shrinkage film layer (3) sequentially comprises a polyethylene micro layer (31), an ethylene-vinyl acetate copolymer micro layer (32), a polyvinylidene chloride micro layer (33), an ethylene-vinyl acetate copolymer micro layer (32) and a polyethylene micro layer (31), a corona micro layer (41) and a corona coating layer (41) from outside to inside.

2. The lithium battery aluminum plastic film with the multilayer structure as claimed in claim 1, wherein the strengthening layer (1) comprises a nylon film layer (11) and a polypropylene carbon fiber composite film layer (12) in sequence from outside to inside.

3. The lithium battery aluminum plastic film with the multilayer structure as claimed in claim 2, wherein the thickness of the nylon film layer (11) is 10-20 um, and the thickness of the polypropylene carbon fiber composite film layer (12) is 30-40 um.

4. The lithium battery aluminum plastic film of a multilayer structure as claimed in claim 1, wherein the outer protective layer (2) comprises a PET cast film outer protective layer (21) and a PA cast film outer protective layer (22) in sequence from outside to inside.

5. The lithium battery aluminum plastic film with a multilayer structure as claimed in claim 4, wherein the thickness of the PET casting film outer protection layer (21) is 15-30 um, and the thickness of the PA casting film outer protection layer (22) is 10-30 um.

6. The lithium battery aluminum plastic film with the multilayer structure as claimed in claim 1, wherein the thickness of the aluminum foil layer (5) is 10-40 um, the thickness of the PP laminating layer (6) is 10-30 um, and the heat sealing layer (7) is a CPP casting film heat sealing layer with a thickness of 20-40 um.

7. The lithium battery aluminum plastic film with a multilayer structure as claimed in claim 1, wherein the thickness of the heat shrinkable film layer (3) is 20-60 um, and the polyethylene microlayers (31), the ethylene-vinyl acetate copolymer microlayers (32) and the polyvinylidene chloride microlayers (33) have the same thickness.

8. The lithium battery aluminum plastic film with the multilayer structure as claimed in claim 1, wherein the thickness of the aluminum-plated film layer (4) is 10-20 um, and the substrate layer (41) is a BOPP evaporation substrate layer or a BOPET evaporation substrate layer.