阅读说明：本技术 极耳胶片、极耳及电池 (Tab film, tab and battery ) 是由 陈忠斌 于 2021-07-23 设计创作，主要内容包括：本发明提供了极耳胶片、极耳及电池,该极耳胶片用于铝塑膜和极耳之间的密封,极耳胶片用于贴敷于极耳的金属带的两面,包括依次层叠复合设置的第一胶体层、第二胶体层和第三胶体层,第一胶体层用于与铝塑膜接触,第三胶体层用于与极耳的金属带接触,第二胶体层的熔点大于第一胶体层和第三胶体层的熔点,第一胶体层包括以下重量组分：90-100份聚丙烯树脂,0.1-0.5份偶联剂；第三胶体层包括以下重量组分：90-100份聚丙烯树脂,2-10份马来酸酐。该发明的极耳胶片与极耳和铝塑膜热封时,形态变化微小,不易出现各层分离的现象,极耳胶片与极耳的金属带和铝塑膜粘接强度高,减小了锂电池使用过程中出现的电池边孔泄露的情况。(The invention provides a tab film, a tab and a battery, wherein the tab film is used for sealing between an aluminum plastic film and the tab, the tab film is used for being pasted on two sides of a metal strip of the tab and comprises a first colloid layer, a second colloid layer and a third colloid layer which are sequentially laminated and compounded, the first colloid layer is used for being contacted with the aluminum plastic film, the third colloid layer is used for being contacted with the metal strip of the tab, the melting point of the second colloid layer is greater than the melting points of the first colloid layer and the third colloid layer, and the first colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 0.1-0.5 part of coupling agent; the third colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 2-10 parts of maleic anhydride. When the tab film, the tab and the aluminum plastic film are subjected to heat sealing, the form change is small, the phenomenon that all layers are separated is not easy to occur, the bonding strength of the tab film, the metal belt of the tab and the aluminum plastic film is high, and the condition that a battery side hole leaks in the use process of a lithium battery is reduced.)

1. The utility model provides a utmost point ear film for sealed between plastic-aluminum membrane and the utmost point ear, utmost point ear film is used for pasting the two sides in the strap of utmost point ear, its characterized in that:

the glue comprises a first glue body layer, a second glue body layer and a third glue body layer which are sequentially laminated and compositely arranged;

the first colloid layer is used for contacting with an aluminum plastic film, the third colloid layer is used for contacting with a metal belt of a tab, the melting point of the second colloid layer is greater than that of the first colloid layer and that of the third colloid layer, and the main materials of the first colloid layer, the second colloid layer and the third colloid layer are all polypropylene resin; the first colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 0.1-0.5 part of coupling agent; the third colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 2-10 parts of maleic anhydride.

2. The tab film according to claim 1, wherein: the first colloid layer and the third colloid layer have the same thickness.

3. The tab film according to claim 2, wherein: the total thickness of the first colloid layer, the second colloid layer and the third colloid layer is 90-110 μm.

4. The tab film according to claim 3, wherein: the thickness of the second colloid layer accounts for 54-66% of the total thickness of the tab film.

5. The tab film according to claim 1, wherein: the melting points of the first colloid layer and the third colloid layer are both 140-160 ℃, and the melting point of the second colloid layer is 160-180 ℃.

6. The tab film according to claim 1, wherein: the tensile strength of the tab film is more than or equal to 40MPa, and the elongation of the tab film is more than or equal to 300%.

7. The tab film according to claim 1, wherein: the first colloid layer is a bright surface layer, and the third colloid layer is a matte surface layer.

8. The tab film according to any one of claims 1 to 6, wherein: the first colloid layer further comprises the following components in parts by weight: 0.03-0.1 part of antioxidant and 0.02-0.08 part of cross-linking agent; the third colloid layer also comprises the following components in parts by weight: 0.1-2 parts of antioxidant and 0.1-1 part of nucleating agent; the second colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin, 0.1-1 part of coupling agent and 0.1-0.5 part of nucleating agent.

9. A pole lug is characterized in that: the tab comprises a metal belt, tab films are attached to two surfaces of the metal belt, and the tab films are the tab films according to any one of claims 1 to 8.

10. A battery, characterized by: the battery comprises an aluminum plastic film and the tab of claim 9, the metal strip of the tab has a first end located outside the aluminum plastic film and a second end located inside the aluminum plastic film, and the first end of the metal strip is fixedly connected with the aluminum plastic film through the tab film.

Technical Field

The invention belongs to the technical field of tab adhesive films, and particularly relates to a tab adhesive film, a tab and a battery.

Background

The lithium battery as a novel secondary battery has the advantages of high energy density and power density, high working voltage, light weight, small volume, long cycle life, good safety, environmental protection and the like, and has wide application prospect in the aspects of portable electric appliances, electric tools, large-scale energy storage, electric traffic power supplies and the like.

A conventional lithium battery generally includes an electrical core composed of a pole piece and a diaphragm, and an aluminum-plastic film encapsulating the electrical core, wherein a tab is welded on the pole piece, and the tab is used as a metal conductor to lead out the positive and negative electrodes of the battery, so as to prevent a short circuit (including a short circuit between a metal strip and an exposed metal at the edge cutting position of the aluminum-plastic film and a metal in the sealing area) between the metal strip of the tab and the aluminum-plastic film when the electrical core is encapsulated, a tab film is usually arranged between the tab and the aluminum-plastic film to perform an insulating function.

When the existing tab film is thermally sealed with an aluminum plastic film, the tab film is greatly deformed, and the condition of leakage of a battery side hole is easy to occur along with the use of a lithium battery.

Disclosure of Invention

The embodiment of the invention aims to provide a tab film, a tab and a battery, and aims to solve the technical problems that the tab film is large in deformation when being thermally sealed with an aluminum plastic film and a battery side hole is easy to leak along with the use of a lithium battery in the prior art.

In order to achieve the purpose, the invention adopts the technical scheme that: the invention provides a tab film, which is used for sealing an aluminum plastic film and a tab, is used for being pasted on two sides of a metal belt of the tab and comprises a first colloid layer, a second colloid layer and a third colloid layer which are sequentially laminated and compositely arranged;

the first colloid layer is used for contacting with an aluminum plastic film, the third colloid layer is used for contacting with a metal belt of a tab, the melting point of the second colloid layer is greater than that of the first colloid layer and that of the third colloid layer, and the main materials of the first colloid layer, the second colloid layer and the third colloid layer are all polypropylene resin; the first colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 0.1-0.5 part of coupling agent; the third colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 2-10 parts of maleic anhydride.

In an embodiment, the first colloid layer and the third colloid layer have the same thickness.

In one embodiment, the total thickness of the first, second and third glue layers is 90-110 μm.

In one embodiment, the thickness of the second colloid layer accounts for 54% -66% of the total thickness of the tab film.

In an embodiment, the melting points of the first gel layer and the third gel layer are both 140-.

In one embodiment, the tensile strength of the tab film is more than or equal to 40MPa, and the elongation of the tab film is more than or equal to 300%.

In an embodiment, the first colloid layer is a bright surface layer, and the third colloid layer is a matte surface layer.

In one embodiment, the first colloid layer further comprises the following components by weight: 0.03-0.1 part of antioxidant and 0.02-0.08 part of cross-linking agent; the third colloid layer also comprises the following components in parts by weight: 0.1-2 parts of antioxidant and 0.1-1 part of nucleating agent; the second colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin, 0.1-1 part of coupling agent and 0.1-0.5 part of nucleating agent.

The invention provides a tab, which comprises a metal belt, wherein tab films are attached to two surfaces of the metal belt, and the tab films are the tab films.

The third aspect of the invention provides a battery, which comprises an aluminum-plastic film and the tab as described above, wherein the metal strip of the tab has a first end located outside the aluminum-plastic film and a second end located inside the aluminum-plastic film, and the first end of the metal strip is fixedly connected with the aluminum-plastic film through the tab film

The invention provides a tab film which comprises a first colloid layer, a second colloid layer and a third colloid layer which are sequentially laminated and compounded, wherein the first colloid layer is used for contacting an aluminum plastic film, the third colloid layer is used for contacting a metal belt of a tab, the melting point of the second colloid layer is greater than the melting points of the first colloid layer and the third colloid layer, when the tab film is thermally sealed with the tab and the aluminum plastic film, the second colloid layer plays a supporting role, the form change of the tab film is small, the separation phenomenon of each layer is not easy to occur, the main materials of the first colloid layer, the second colloid layer and the third colloid layer are all polypropylene resin, and the first colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 0.1-0.5 part of coupling agent, wherein the coupling agent can improve the bonding strength of the polypropylene resin and the aluminum plastic film, and the third colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 2-10 parts of maleic anhydride, wherein the maleic anhydride can improve the bonding property and compatibility of polar materials and non-polar materials, so that the bonding strength of the tab film, the aluminum plastic film and the tab metal belt is high, and the condition of battery side hole leakage in the use process of the lithium battery is reduced.

The tab provided by the invention comprises a metal belt and tab films respectively attached to two sides of the metal belt, wherein the tab films are the tab films, when the tab films are thermally sealed with the tab and an aluminum plastic film, the second colloid layer plays a supporting role, the tab films have small form change, the phenomenon of separation of each layer is not easy to occur, the bonding strength of the tab films with the metal belt and the aluminum plastic film of the tab is high, and the condition of battery side hole leakage in the use process of a lithium battery is reduced.

The battery provided by the invention comprises the aluminum-plastic film and the tab, wherein the metal belt of the tab is provided with a first end positioned outside the aluminum-plastic film and a second end positioned inside the aluminum-plastic film, and the first end of the metal belt is fixedly connected with the aluminum-plastic film through the tab film, so that the leakage of a battery side hole in the use process of the battery is reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a tab film according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a tab film, an aluminum plastic film and a tab provided by an embodiment of the invention;

fig. 3 is a stress-deformation curve diagram of a tab film tensile test provided by an embodiment of the invention;

fig. 4 is a graph showing a test curve of the bonding strength of the tab film according to the embodiment of the present invention (wherein, the dotted line represents the existing tab film, and the solid line represents the tab film according to the embodiment of the present invention).

Wherein, in the figures, the respective reference numerals:

1-tab film;

2-an aluminum plastic film;

3, pole ear;

11-a first colloidal layer;

12-a second colloidal layer;

13-third colloidal layer.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions 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 some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "comprises" and "comprising," and any variations thereof, as used herein, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In addition, in the present application, unless otherwise expressly specified or limited, the terms "connected," "secured," "mounted," and the like are to be construed broadly, such as to encompass both mechanical and electrical connections; the terms may be directly connected or indirectly connected through an intermediate medium, and may be used for communicating between two elements or for interacting between two elements, unless otherwise specifically defined, and the specific meaning of the terms in the present application may be understood by those skilled in the art according to specific situations.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must be in a particular orientation, constructed and operated in a particular orientation, and are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

The tab film, the tab and the battery according to the present invention will be described in detail with reference to specific embodiments.

Fig. 1 is a schematic structural diagram of a tab film provided by an embodiment of the present invention, and fig. 2 is a schematic structural diagram of a tab film, an aluminum-plastic film and a tab provided by an embodiment of the present invention, referring to fig. 1 and fig. 2, a first aspect of an embodiment of the present invention provides a tab film 1 for sealing between an aluminum-plastic film 2 and a tab 3, where the tab film 1 is used for being attached to two sides of a metal strip of the tab 3, and the tab film 1 includes a first colloid layer 11, a second colloid layer 12 and a third colloid layer 13, which are sequentially stacked and compositely disposed;

the first colloid layer 11 is used for contacting with the aluminum plastic film 2, the third colloid layer 13 is used for contacting with a metal belt of a tab, the melting point of the second colloid layer 12 is greater than the melting points of the first colloid layer 11 and the third colloid layer 13, and the main materials of the first colloid layer 11, the second colloid layer 12 and the third colloid layer 13 are all polypropylene resin; the first colloid layer 11 comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 0.1-0.5 part of coupling agent; the third colloid layer 13 comprises the following components by weight: 90-100 parts of polypropylene resin and 2-10 parts of maleic anhydride.

The tab film 1 is an insulated part on the tab 3, and is used for preventing a short circuit between the metal belt and the aluminum plastic film 2 during battery packaging, and preventing liquid leakage by being heated and sealed and bonded with the aluminum plastic film 2 during packaging.

The melting point of the second colloid layer 12 of the present embodiment is greater than the melting points of the first colloid layer 11 and the third colloid layer 13, and the second colloid layer 12 plays a supporting role when the tab film 1 is hermetically connected with the metal strips of the aluminum plastic film 2 and the tab 3. In this embodiment, the thickness of the first colloid layer 11 may be 20um ± 10%, the thickness of the second colloid layer 12 is 60um ± 10%, and the thickness of the third colloid layer 13 is 20um ± 10%, and this embodiment does not particularly limit the specific thicknesses of the first colloid layer 11, the second colloid layer 12, and the third colloid layer 13.

When the tab film of the embodiment is packaged in a battery, the first colloid layer 11 is used for contacting the aluminum plastic film 2, the third colloid layer 13 is used for contacting the metal strip of the tab 3, and the main materials of the first colloid layer 11, the second colloid layer 12 and the third colloid layer 13 are all polypropylene resin, so that the tab film is nontoxic, odorless, low in density, and superior to polyethylene in strength, rigidity, hardness and heat resistance. The first colloid layer 11 of this embodiment includes 0.1-0.5 weight parts of coupling agent, which can improve the adhesion strength, water resistance, weather resistance, etc. of the polypropylene resin material and the aluminum plastic film. The third colloid layer 13 of the embodiment includes 2-10 parts by weight of maleic anhydride, which can improve the adhesion and compatibility of polar materials and non-polar materials, so that the bonding strength of the tab film 1, the aluminum plastic film 2 and the tab metal strip is high, and the leakage of the battery side hole in the use process of the lithium battery is reduced. The pole lug film bonding strength of the embodiment of the application is more stable than that of the existing pole lug film.

The tab film provided by the embodiment of the invention comprises a first colloid layer, a second colloid layer and a third colloid layer which are sequentially laminated and compositely arranged, wherein the first colloid layer is used for contacting with an aluminum plastic film, the third colloid layer is used for contacting with a metal belt of a tab, the melting point of the second colloid layer is greater than the melting points of the first colloid layer and the third colloid layer, when the tab film is thermally sealed with the tab and the aluminum plastic film, the second colloid layer plays a supporting role, the form change of the tab film is tiny, the phenomenon of separation of each layer is not easy to occur, the main materials of the first colloid layer, the second colloid layer and the third colloid layer are all polypropylene resin, the first colloid layer comprises 0.1-0.5 part by weight of coupling agent, wherein the coupling agent can improve the bonding strength of the polypropylene resin and the aluminum plastic film, the third colloid layer comprises 2-10 parts by weight of maleic anhydride, and the bonding property and compatibility of polar materials and non-polar materials can be improved by the maleic anhydride, therefore, the bonding strength of the tab film, the aluminum plastic film and the tab metal belt is high, and the leakage of the battery side hole in the use process of the lithium battery is reduced.

In a specific embodiment, the thicknesses of the first colloid layer 11 and the third colloid layer 13 are the same. The first colloid layer 11 of the tab film 1 of this embodiment and the thickness of the third colloid layer 13 are both 20um, the thickness of the third colloid layer 13 is 60um, and the total thickness of this tab film 1 is 100 um.

In a specific embodiment, the total thickness of the first colloid layer 11, the second colloid layer 12 and the third colloid layer 13 is 90-110 μm. Preferably, the thickness of the second colloid layer 12 accounts for 54% -66% of the total thickness of the tab film 1.

Further, the melting points of the first colloid layer 11 and the third colloid layer 13 are both 140-. The melting point of the first colloid layer 11 and the third colloid layer 13 of this embodiment is lower than that of the second colloid layer 12, and the second colloid layer 12 has a small form change when the tab 3 and the aluminum plastic film 2 are heat sealed, so that the supporting effect is achieved, and the phenomenon of separation between each layer of the tab film 1 is avoided.

Preferably, the tensile strength of the tab film 1 is not less than 40MPa, and the elongation of the tab film 1 is not less than 300%. In an embodiment, fig. 3 is a stress-deformation curve diagram of a tab film tensile test according to an embodiment of the present invention, please refer to fig. 3, where the tab film has a tensile strength of 62.8MPa and an elongation at break of 878.048%. Fig. 4 is a graph showing a bonding strength test curve of a tab film according to an embodiment of the present invention, please refer to fig. 4, wherein a dotted line is the bonding strength of the conventional tab film, and the bonding strength of the tab film according to the embodiment of the present invention is shown in the graph, it can be seen that the bonding strength of two tab films is relatively stable within 30 days, and the bonding strength of the tab film according to the embodiment of the present invention is significantly superior to the bonding strength of the conventional tab film in stability between 30 days and 70 days.

Further, in this embodiment, the first colloid layer 11 is a bright surface layer, and the third colloid layer 13 is a matte surface layer.

Preferably, in the above embodiment, the first colloid layer 11 further includes the following components by weight: 0.03-0.1 part of antioxidant and 0.02-0.08 part of cross-linking agent, wherein the antioxidant is antioxidant BHT (butylated hydroxytoluene), and can delay or inhibit the polymer oxidation process, thereby preventing the tab film from aging and prolonging the service life of the tab film. The crosslinking agent of this embodiment is a crosslinking agent dcp (crosslinking agent dcp), which is helpful for improving the insulation and heat resistance of the first colloid layer 11; the third colloid layer 13 further comprises the following components by weight: 0.1-2 parts of antioxidant and 0.1-1 part of nucleating agent, wherein the nucleating agent can accelerate the crystallization rate, increase the crystallization density and promote the grain size to be micronized, and the physical and mechanical properties of shortening the molding period, improving the transparency, surface gloss, tensile strength, rigidity, heat deformation temperature, impact resistance, creep resistance and the like of the product are achieved. The antioxidant in the embodiment can be antioxidant BHT, and can delay or inhibit the polymer oxidation process, so as to prevent the polymer from aging and prolong the service life of the tab film; the second colloid layer 12 comprises the following components by weight: 90-100 parts of polypropylene resin, 0.1-1 part of coupling agent, 0.1-0.5 part of nucleating agent, wherein the nucleating agent of the second colloid layer 12 can accelerate crystallization rate, increase crystallization density and promote grain size refinement, thereby achieving the physical and mechanical properties of shortening molding cycle, improving product transparency, surface gloss, tensile strength, rigidity, thermal deformation temperature, impact resistance, creep resistance and the like, and the coupling agent can improve the bonding strength, water resistance, weather resistance and the like of polypropylene resin materials and aluminum plastic films. In the manufacturing process of the tab film, the first colloid layer 11, the second colloid layer 12 and the third colloid layer 13 respectively enter three extruders and then pass through a distributor to form a three-layer co-extrusion structure, wherein the thickness of the three layers is controlled by a metering pump, so that a three-layer glue cavity co-extrusion structure is formed and distribution of the three layers is met.

In the above examples, the antioxidant may be a peroxide decomposition type antioxidant, a radical scavenging type antioxidant, or a metal deactivation type antioxidant. The coupling agent of the above embodiments may be a coupling agent such as silanes, titanates, aluminates, organochromosomes, borides, phosphates, zirconates, stannates, etc., and the nucleating agent of the above embodiments may be an inorganic nucleating agent, an organic nucleating agent, or a polymeric nucleating agent.

When the tab film provided by the embodiment of the invention is thermally sealed with the tab and the aluminum plastic film, the second colloid layer plays a supporting role, the tab film has small form change, and the separation of each layer is not easy to occur, the main materials of the first colloid layer, the second colloid layer and the third colloid layer are all polypropylene resins, and the first colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 0.1-0.5 part of coupling agent, wherein the coupling agent can improve the bonding strength of the polypropylene resin and the aluminum plastic film, and the third colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 2-10 parts of maleic anhydride, wherein the maleic anhydride can improve the bonding property and compatibility of polar materials and non-polar materials, so that the bonding strength of the tab film, the aluminum plastic film and the tab metal belt is high, and the condition of battery side hole leakage in the use process of the lithium battery is reduced.

The second aspect of the embodiment of the present invention provides a tab 3, where the tab 3 includes a metal belt, tab films 1 are attached to both sides of the metal belt, and the tab films 1 are the tab films according to the above embodiment.

For example: the tab film comprises a first colloid layer 11, a second colloid layer 12 and a third colloid layer 13 which are sequentially laminated and compositely arranged;

the first colloid layer 11 is used for contacting with the aluminum plastic film 2, the third colloid layer 13 is used for contacting with a metal belt of a tab, the melting point of the second colloid layer 12 is greater than the melting points of the first colloid layer 11 and the third colloid layer 13, and the main materials of the first colloid layer 11, the second colloid layer 12 and the third colloid layer 13 are all polypropylene resin; the first colloid layer 11 comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 0.1-0.5 part of coupling agent; the third colloid layer 13 comprises the following components by weight: 90-100 parts of polypropylene resin and 2-10 parts of maleic anhydride.

The tab 3 provided by the embodiment of the invention comprises a metal belt and tab films 1 respectively attached to two sides of the metal belt, wherein the tab films 1 are the tab films, when the tab films 1, the tab 3 and the aluminum plastic film 2 are thermally sealed, the second colloid layer plays a supporting role, the tab films have tiny form change, the phenomenon of separation of each layer is not easy to occur, the bonding strength of the tab films, the metal belt of the tab and the aluminum plastic film 2 is high, and the condition of battery side hole leakage in the use process of a lithium battery is reduced.

A third aspect of the embodiments of the present invention provides a battery, which includes an aluminum plastic film and the tab as described above, where the metal strip of the tab has a first end located outside the aluminum plastic film and a second end located inside the aluminum plastic film, and the first end of the metal strip is fixedly connected to the aluminum plastic film through the tab film.

The tab film comprises a first colloid layer, a second colloid layer and a third colloid layer which are sequentially laminated and compounded;

the first colloid layer is used for contacting with an aluminum plastic film, the third colloid layer is used for contacting with a metal belt of a tab, the melting point of the second colloid layer is greater than that of the first colloid layer and that of the third colloid layer, and the main materials of the first colloid layer, the second colloid layer and the third colloid layer are all polypropylene resin; the first colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 0.1-0.5 part of coupling agent; the third colloid layer comprises the following components in parts by weight: 90-100 parts of polypropylene resin and 2-10 parts of maleic anhydride.

The battery provided by the invention comprises the aluminum-plastic film and the tab, wherein the metal belt of the tab is provided with a first end positioned outside the aluminum-plastic film and a second end positioned inside the aluminum-plastic film, and the first end of the metal belt is fixedly connected with the aluminum-plastic film through the tab film, so that the leakage of a battery side hole in the use process of the battery is reduced.

The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.