WO2024050688A1

WO2024050688A1 - Composite polymer film, manufacturing method therefor, metallized composite polymer film, and use

Info

Publication number: WO2024050688A1
Application number: PCT/CN2022/117277
Authority: WO
Inventors: 朱中亚; 王帅; 夏建中; 李学法; 张国平
Original assignee: 扬州纳力新材料科技有限公司
Priority date: 2022-09-06
Filing date: 2022-09-06
Publication date: 2024-03-14

Abstract

The present application relates to a composite polymer film, a manufacturing method therefor, a metallized composite polymer film, and the use. The composite polymer film of the present application comprises a core layer, a surface layer I and a surface layer II, the core layer being located between the surface layer I and the surface layer II. In percentage by mass, the manufacturing raw materials of the core layer comprise: 98%-99.8% of a polyester material, 0.1%-1% of an inorganic nano-material and 0.1%-1% of an antioxidant, and the manufacturing raw materials of each of the surface layer I and the surface layer II independently comprise: 88%-98.8% of a polyester material, 1%-10% of a nano-oxide and 0.2%-2% of an additive.

Description

Composite polymer film, method of manufacturing same, metallized composite polymer film and applications

Technical field

The present application relates to the field of battery technology, and in particular to a composite polymer film, its manufacturing method, metallized composite polymer film and applications.

Background technique

Metalized polymer films are widely used in electronics, packaging, printing and other fields due to their excellent conductivity, barrier, flexibility and light weight properties. Metalized polymer film products include composite current collectors, thin film electrodes, packaging aluminized films, printed films, etc. The manufacturing process of composite current collectors is usually as follows: using physical vapor deposition method to deposit a layer of metal material on a polymer film to create a surface metallized film with a certain conductivity, which is a composite current collector. Compared with traditional current collectors, composite current collectors based on polymers have lower costs, lighter weight, and better internal insulation. Therefore, applying the composite current collectors to batteries can reduce the cost of batteries and improve battery performance. Battery energy density and safety. However, polyester films with traditional technology have problems such as weak surface adhesion, low mechanical strength, and poor heat resistance. When compounding polyester films with metal materials, the bonding strength between the two decreases due to poor affinity. lower.

Contents of the invention

According to various embodiments of the present application, a composite polymer film, a manufacturing method thereof, a metallized composite polymer film and applications are provided.

The technical solutions adopted in this application are as follows:

The present application provides a composite polymer film. The composite polymer film includes a core layer, a surface layer one and a surface layer two, and the core layer is located between the surface layer one and the surface layer two;

In terms of mass percentage, the raw materials for manufacturing the core layer include: 98% to 99.8% polyester materials, 0.1% to 1% inorganic nanomaterials and 0.1% to 1% antioxidants. The surface layer one and the surface layer two are The manufacturing raw materials each independently include: 88% to 98.8% polyester material, 1% to 10% nano oxide and 0.2% to 2% additives.

In some embodiments, the nano-oxide includes one of aluminum oxide, silicon dioxide, titanium dioxide, zinc oxide, copper oxide, magnesium oxide, ferric oxide, ferric tetroxide, zirconium dioxide and tin dioxide. Kind or variety.

In some embodiments, the inorganic nanomaterial includes one or more of nanooxide, graphene, graphene oxide, carbon nanotubes and carbon nanofibers.

In some embodiments, the polyester material includes polyethylene terephthalate (PET), polyethylene 2,6-naphthalate (PEN), polybutylene terephthalate (PBT), poly1,4-cyclohexanedimethanol terephthalate (PCT), polyethylene terephthalate-1,4-cyclohexanedimethanol (PETG), poly2, 6-Trimethylene naphthalate (PTN), polytrimethylene terephthalate (PTT), polybutylene 2,6-naphthalate (PBN), polybutylene 2,5-furandicarboxylate, One or more of polybutylene adipate terephthalate (PBAT), polyarylate (PAR) and their derivatives.

In some embodiments, the additives include antioxidants and slip agents;

Optionally, the antioxidant includes one or more of phosphonate and bisphenol A phosphite;

Optionally, the slip agent includes one or more of calcium carbonate, talc, kaolin, diatomaceous earth, siloxane, clay, mica, aluminum silicate, potassium phosphate, barium sulfate, and acrylate.

In some embodiments, the composite polymer film has a thickness of 1 to 50 μm;

Optionally, the thickness of the core layer, the first surface layer and the second surface layer account for 70% to 90%, 5% to 15%, and 5% to 15% of the thickness of the composite polymer film, respectively. And the thickness of the first surface layer and the second surface layer are equal.

This application also provides a manufacturing method for the above-mentioned composite polymer film, including the following steps:

S1. Manufacture polyester slices A, polyester slices B and polyester slices C respectively, wherein, in terms of mass percentage, the polyester slices A and polyester slices C are each independently made of 88% to 98.8% polyester material. , 1% to 10% nano oxide and 0.2% to 2% additives. The polyester slice B is made of 98% to 99.8% polyester material, 0.1% to 1% inorganic nanomaterials and 0.1% to 1% Made from antioxidants;

S2. The polyester slice A, the polyester slice B and the polyester slice C are melted and extruded to obtain a molten polyester material having a core layer, a surface layer one and a surface layer two. The core layer is located at Between the surface layer one and the surface layer two;

S3. Perform molding treatment and heat treatment on the molten polyester material in sequence.

In some embodiments, the heat treatment process of step S3 includes the following steps:

The first stage: the heat treatment temperature is 130~160℃, and the heat treatment time is 0.5~2min;

Second stage: The heat treatment temperature is 160~220℃, and the heat treatment time is 0.5~5min;

The third stage: the heat treatment temperature is 130~160℃, and the heat treatment time is 0.5~2min.

The present application also provides a metallized composite polymer film, which includes a composite polymer film and a metal conductive layer. The composite polymer film is the above composite polymer film or a composite polymer film produced by the above manufacturing method. A metal conductive layer is disposed on at least one surface of the composite polymer film;

Optionally, the material of the metal conductive layer includes one or more of copper, copper alloy, aluminum, aluminum alloy, nickel, nickel alloy, titanium and silver.

In some embodiments, the thickness of the metal conductive layer ranges from 20 to 2000 nm.

The present application also provides a composite current collector, including the above-mentioned metallized composite polymer film.

In some embodiments, the composite current collector further includes a protective layer located on the metal conductive layer of the metallized composite polymer film.

In some embodiments, the protective layer includes nickel, chromium, nickel-based alloys, copper-based alloys, copper oxide, aluminum oxide, nickel oxide, chromium oxide, cobalt oxide, graphite, carbon black, acetylene black, Ketjen black, One or more of carbon nanoquantum dots, carbon nanotubes, carbon nanofibers and graphene.

In some embodiments, the thickness of the protective layer is 100-150 nm.

Furthermore, this application also provides an electrode pole piece, including the above composite current collector.

Furthermore, this application also provides a battery including the above-mentioned electrode pole piece.

Furthermore, this application also provides an electronic device, including the above-mentioned battery.

The details of one or more embodiments of the application are set forth in the description below. Other features, objects and advantages of the application will become apparent from the description and claims.

Detailed ways

The technical solution of the present application will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing specific embodiments only and is not intended to limit the application. As used herein, the term "one or more" includes any and all combinations of one or more of the associated listed items.

In this application, when it comes to numerical intervals, unless otherwise specified, the above numerical interval is considered to be continuous and includes the minimum value and maximum value of the range, as well as every value between such minimum value and maximum value. Further, when a range refers to an integer, every integer between the minimum value and the maximum value of the range is included. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein are to be understood to include any and all subranges subsumed therein.

One embodiment of the present application provides a composite polymer film. The composite polymer film includes a core layer, a surface layer one and a surface layer two, and the core layer is located between the surface layer one and the surface layer two;

In terms of mass percentage, the manufacturing raw materials of the core layer include: 98% to 99.8% polyester materials, 0.1% to 1% inorganic nanomaterials and 0.1% to 1% antioxidants. The manufacturing raw materials of surface layer one and surface layer two independently include : 88% ~ 98.8% polyester material, 1% ~ 10% nano oxide and 0.2% ~ 2% additives.

Due to the weak surface polarity of the polyester film (35mN/m), its bonding force with metal materials is poor; the tensile strength of the polyester film is generally less than 250MPa, and in the PVD (physical vapor deposition) system environment due to winding The pressure of the system, the bombardment of metal atoms, and the increase in the surface temperature of the polyester film make the polyester film prone to fracture; in addition, the heat resistance of the polyester film is poor and it is easy to shrink when exposed to heat. The bombardment and deposition of high-temperature metal atoms will Under such conditions, shrinkage is prone to occur, causing product defects and poor heat resistance of the composite current collector. Moreover, when the composite current collector is used in batteries, the coating and composite molding processes involved affect the tensile strength of the polyester film. It also puts forward relatively high requirements.

In view of this, this application provides a composite polymer film that utilizes the intermolecular force between inorganic nanomaterials and polyester materials to improve the mechanical properties and heat resistance of the core layer, and the nano-oxidation in the surface layer one and surface layer two The material segregates to the surface of surface layer one and surface layer two during the film formation and cooling process, which can improve the surface polarity and heat resistance of both. Therefore, the composite polymer film of the present application has the advantages of good surface adhesion, high mechanical strength, good processability and good heat resistance. The composite polymer film is used as the base film to manufacture a metallized composite polymer film, and the bonding strength between the composite polymer film and the surface metal conductive layer is also greatly improved. The content of inorganic nanomaterials in the core layer of the composite polymer film of the present application, and the content of nanooxides in the surface layer one and surface layer two cannot be too low or too high. If the content of inorganic nanomaterials and nanooxides is too low, the composite The performance improvement of the polymer membrane is not obvious, and if its content is too high, it is easy to cause membrane defects.

In some embodiments, the nano-oxide includes one of aluminum oxide, silicon dioxide, titanium dioxide, zinc oxide, copper oxide, magnesium oxide, ferric oxide, ferric tetroxide, zirconium dioxide and tin dioxide, or Various.

In some embodiments, the shape of the nanooxide includes one or more of spherical, linear, and tubular shapes.

In some embodiments, the diameter of the spherical nanooxide is 5-80nm, the diameter of the linear nanooxide is 3-30nm and the length is 0.1-1 μm, and the diameter of the tubular nanooxide is 5-50nm and the length is 0.1-1μm. 1μm.

In some embodiments, the sheet diameter of graphene is 0.2-2 μm, the thickness is 0.8-0.9 nm, and the single-layer rate is 60-80%; the sheet diameter of graphene oxide is 0.2-2 μm, and the thickness is 0.8-1.2 nm; Carbon nanotubes are single-walled carbon nanotubes with a diameter of 4 to 5 nm and a length of 0.2 nm to 2 μm; carbon nanofibers have a diameter of 20 to 80 nm and a length of 0.2 to 2 μm.

It should be explained that this application needs to control the size of the nano-oxides in the surface layer one and surface layer two. If the size of the nano-oxides in the surface layer one and surface layer two is too small, it will not be conducive to improving the performance of the composite polymer film. If its size If it is too large, on the one hand, it is difficult to segregate to the surface of surface layer one and surface layer two, which limits the improvement of the bonding force between the composite polymer film and the metal conductive layer. On the other hand, it is easy to cause film defects.

It can be understood that the nano-oxide includes any one of aluminum oxide, silicon dioxide, titanium dioxide, zinc oxide, copper oxide, magnesium oxide, ferric oxide, ferric tetroxide, zirconium dioxide and tin dioxide, or It includes mixtures of aluminum oxide, silicon dioxide, titanium dioxide, zinc oxide, copper oxide, magnesium oxide, ferric oxide, ferric tetroxide, zirconium dioxide and tin dioxide in any proportion.

In some embodiments, the inorganic nanomaterials include one or more of nanooxides, graphene, graphene oxide, carbon nanotubes, and carbon nanofibers.

It can be understood that the inorganic nanomaterials include any one of nanooxides, graphene, graphene oxide, carbon nanotubes and carbon nanofibers, or include nanooxides, graphene, graphene oxide, carbon nanotubes and carbon. A mixture of nanofibers in any proportion.

In some embodiments, polyester materials include polyethylene terephthalate (PET), polyethylene 2,6-naphthalate (PEN), polybutylene terephthalate (PBT) ), poly1,4-cyclohexanedimethanol terephthalate (PCT), polyethylene terephthalate-1,4-cyclohexanedimethanol (PETG), poly2,6- Trimethylene naphthalate (PTN), polytrimethylene terephthalate (PTT), polybutylene 2,6-naphthalate (PBN), polybutylene 2,5-furandicarboxylate, polyhexane One or more of butylene terephthalate (PBAT), polyarylate (PAR) and their derivatives.

It can be understood that polyester materials include polyethylene terephthalate (PET), polyethylene 2,6-naphthalate (PEN), polybutylene terephthalate (PBT), Poly 1,4-cyclohexanedimethanol terephthalate (PCT), polyethylene terephthalate-1,4-cyclohexanedimethanol (PETG), poly 2,6-naphthalene dicarboxylate Propylene glycol formate (PTN), polytrimethylene terephthalate (PTT), polybutylene 2,6-naphthalate (PBN), polybutylene 2,5-furandicarboxylate, polyadipic acid Any one of butylene terephthalate (PBAT), polyarylate (PAR) and their derivatives, or polyester materials including polyethylene terephthalate (PET), poly2, 6-Ethylene naphthalate (PEN), polybutylene terephthalate (PBT), poly1,4-cyclohexanedimethanol terephthalate (PCT), polyterephthalate Ethylene glycol ester-1,4-cyclohexanedimethanol (PETG), polytrimethylene 2,6-naphthalate (PTN), polytrimethylene terephthalate (PTT), poly2,6-naphthalene In polybutylene dicarboxylate (PBN), polybutylene 2,5-furandicarboxylate, polybutylene adipate terephthalate (PBAT), polyarylate (PAR) and their derivatives A mixture of many kinds in any proportion.

In some embodiments, additives include antioxidants and slip agents;

It is understood that the antioxidant includes a phosphonate or bisphenol A phosphite, or the antioxidant includes a mixture of a phosphonate and bisphenol A phosphite in any proportion.

It can be understood that the slip agent includes any one of calcium carbonate, talc, kaolin, diatomaceous earth, siloxane, clay, mica, aluminum silicate, potassium phosphate, barium sulfate, acrylate, or calcium carbonate. , talc, kaolin, diatomaceous earth, siloxane, clay, mica, aluminum silicate, potassium phosphate, barium sulfate and acrylate mixture in any proportion.

In some embodiments, the composite polymer film has a thickness of 1 to 50 μm;

Optionally, the thicknesses of the core layer, surface layer one and surface layer two account for 5% to 15%, 70% to 90%, 70% to 90% of the thickness of the composite polymer film in order, and the thickness of surface layer one and surface layer two is equal.

In some embodiments, the thickness of the composite polymer film ranges from 2 to 20 μm.

It can be understood that the thickness of the composite polymer film can be any value between 1 to 50 μm or 2 to 20 μm, such as: 1 μm, 2 μm, 4 μm, 8 μm, 12 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm , 55μm, etc.; the percentage of the thickness of the core layer, surface layer one and surface layer two to the thickness of the composite polymer film can be any value between 70% to 90%, 5% to 15%, 5% to 15%, respectively. Composite polymerization The proportion of the thickness of the core layer, surface layer one and surface layer two in the film thickness can be, for example, 90%, 5%, 5%; or 84%, 8%, 8%; or 80%, 10%, 10% ; Or 76%, 12%, 12%; Or 70%, 15%, 15%.

S1. Manufacture polyester slices A, polyester slices B and polyester slices C respectively. In terms of mass percentage, polyester slices A and polyester slices C are independently composed of 88% to 98.8% polyester material, 1 %~10% nano oxides and 0.2%~2% additives. Polyester chip B is made from 98%~99.8% polyester materials, 0.1%~1% inorganic nanomaterials and 0.1%~1% antioxidants. ;

S2. Melt extrusion of polyester slice A, polyester slice B and polyester slice C to obtain a molten polyester material having a core layer, surface layer one and surface layer two, with the core layer located between surface layer one and surface layer two;

It should be explained that polyester slice A forms the first surface layer, polyester slice B forms the core layer, and polyester slice C forms the second surface layer.

During the manufacturing process of the composite polymer film of the present application, nano-oxides segregate to the surface of the composite polymer film to form an organic-inorganic hybrid layer with a dominant nano-oxide content, taking advantage of the good adhesion between nano-oxides and metal materials. , thereby improving the adhesion between the composite polymer film and the metal conductive layer.

In some embodiments, the forming process of step S3 includes the following steps:

(1) Casting sheet: cast the molten polyester material in step S2 onto the casting roller, and undergo the casting roller and water cooling treatment to obtain the cast sheet;

(2) Longitudinal stretching: Preheat the above-mentioned cast sheet at 70 to 100°C and then perform longitudinal stretching to obtain a film sheet, which is then heat-set at 165 to 180°C and cooled at 30 to 50°C. Processing, wherein the longitudinal stretching ratio is (3~5):1, and the longitudinal stretching temperature is 80~120°C;

(3) Transverse stretching: The above film is preheated at 80 to 120°C and then transversely stretched, then heat set at 150 to 250°C, and cooled at 80 to 150°C, where, The transverse stretching ratio is (3~5):1, and the transverse stretching temperature is 90~140°C.

The present application also provides a metallized composite polymer film, including a composite polymer film and a metal conductive layer. The composite polymer film is the above composite polymer film or a composite polymer film produced by the above manufacturing method. The metal conductive layer disposed on at least one surface of the composite polymer film;

It can be understood that the metal conductive layer can be made of one of copper, copper alloy, aluminum, aluminum alloy, nickel, nickel alloy, titanium and silver, or can also be made of copper, copper alloy, aluminum, aluminum alloy, nickel, nickel Available in a variety of alloys, titanium and silver.

In some embodiments, the thickness of the metal conductive layer ranges from 30 to 1000 nm.

It can be understood that the thickness of the metal conductive layer can be any value between 20 to 2000nm or 30 to 1000nm. For example, the thickness of the metal conductive layer can be 20nm, 25nm, 30nm, 50nm, 150nm, 250nm, 350nm, 450nm, 550nm, 650nm, 750nm, 850nm, 950nm, 1000nm, 1050nm, 1150nm, 1250nm, 1350nm, 1450nm, 1550nm, 1650nm, 1750nm, 1850nm, 1950nm, 2000nm.

In some embodiments, the manufacturing method of the metal conductive layer includes one or more of physical vapor deposition, electroplating and chemical plating;

Optionally, the above physical vapor deposition method includes one or more of a resistance heating vacuum evaporation method, an electron beam heating vacuum evaporation method, a laser heating vacuum evaporation method, and a magnetron sputtering method.

In some embodiments, the composite polymer film in the metallized composite polymer film has a thickness of 1 to 20 μm.

It can be understood that the thickness of the composite polymer film in the metalized composite polymer film can be any value between 1 and 20 μm. For example, the thickness of the composite polymer film in the metalized composite polymer film can be 1 μm, 3 μm, 5μm, 7μm, 9μm, 11μm, 13μm, 15μm, 17μm, 19μm, 20μm.

In some embodiments, the protective layer includes nickel, chromium, nickel-based alloy, copper-based alloy, copper oxide, aluminum oxide, nickel oxide, chromium oxide, cobalt oxide, graphite, carbon black, acetylene black, Ketjen black, carbon nanoparticles One or more of quantum dots, carbon nanotubes, carbon nanofibers and graphene.

In some embodiments, the thickness of the protective layer ranges from 10 to 150 nm.

In some embodiments, the thickness of the protective layer ranges from 20 to 100 nm.

It can be understood that the thickness of the protective layer can be any value between 10 to 150nm or 20 to 100nm. For example, the thickness of the protective layer can be 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 45nm, 55nm, 65nm, 75nm, 85nm, 95nm, 100nm, 105nm, 115nm, 125nm, 135nm, 145nm, 150nm.

In some embodiments, the manufacturing method of the protective layer includes one or more of a physical vapor deposition method, an in-situ forming method, and a coating method.

In some embodiments, the above physical vapor deposition method includes one or more of a vacuum evaporation method and a magnetron sputtering method.

In some embodiments, the above-mentioned in-situ forming method includes a method of forming a metal oxide passivation layer in-situ on the surface of the metal conductive layer.

In some embodiments, the above-mentioned coating method includes one or more of a die coating method, a blade coating method, and an extrusion coating method.

In some embodiments, the protective layer is composed of two layers. The materials of the two protective layers may be the same or different, and the thickness of the two protective layers may be equal or unequal.

It can be understood that the electrode sheet of the present application can be mixed with positive electrode active material/negative electrode active material, conductive agent, binder and solvent to form a slurry, and the slurry can be prepared using methods well known to those skilled in the art for preparing electrode sheets. Coated on the composite current collector of the present application, the electrode pieces can be divided into positive electrode pieces and negative electrode pieces according to different active materials. The preparation method of electrode pole pieces is well known to those skilled in the art and is not particularly limited in this application.

It can be understood that the battery of the present application can be a lithium ion secondary battery, a lithium ion polymer secondary battery, a lithium metal secondary battery or a lithium polymer secondary battery, etc. There is no particular limitation on the battery in the present application.

It can be understood that the electronic device in this application is not particularly limited, and may be, for example, an electric vehicle, a smart home appliance, a digital camera, a mobile phone, a computer, etc. The battery in this application may be used as a power source or energy storage unit in an electronic device.

The present application will be further described in detail below in conjunction with specific examples and comparative examples.

Example 1

The polyester material of the core layer, surface layer one and surface layer two is made of polyethylene terephthalate (PET) resin with an intrinsic viscosity of 0.731dL/g and a molecular weight distribution of 2.2.

The inorganic nanomaterial of the core layer is spherical nano-alumina (average diameter: 40nm), and the additive of the core layer is antioxidant 1222.

The nano-oxides of surface layer one and surface two are both spherical nano-silica (average diameter: 30nm), the antioxidant is antioxidant 1222, and the slip agent is calcium carbonate.

The manufacturing method of composite polymer membrane includes the following steps:

S1. Manufacturing polyester chips A, polyester chips B and polyester chips C

In terms of mass percentage, polyester chips A and polyester chips C are made by heating, melting, mixing, extruding and The polyester slice B is obtained by sequentially heating, melting, mixing, extruding and forming the 99.4% PET resin, 0.1% nano-alumina and 0.5% antioxidant 1222. The polyester slice A is , polyester slice B and polyester slice C are transported to the crystallizer and processed at 140°C for 40 minutes, and then the crystallized polyester slice A, polyester slice B and polyester slice C are transported to the drying tower. Dry at 150℃ for 160min;

S2. Manufacturing molten polyester material

The polyester chips A, polyester chips B and polyester chips C obtained in step S1 are added to different twin-screw extruders, melted at 280°C, and the melt is extruded through the die with the help of a metering pump to obtain a product with The molten polyester material of the core layer, surface layer one and surface layer two, the core layer is located between the surface layer one and the surface layer two, wherein the extrusion volume ratio of the core layer, surface layer one and surface layer two is 80%, 10% and 10% in order (mass ratio), polyester slice A forms the surface layer one, polyester slice B forms the core layer, and polyester slice C forms the surface layer two;

S3. Manufacturing composite polymer membrane

S3.1, forming processing

(2) Longitudinal stretching: Preheat the above-mentioned cast sheet at 90°C and then perform longitudinal stretching treatment to obtain a film sheet, which is heat-set at 170°C and then cooled at 40°C, wherein the longitudinal stretching The stretch ratio is 4:1, and the longitudinal stretching temperature is 110°C;

(3) Transverse stretching: The above film is preheated at 90°C and then stretched transversely, heat set at 170°C, and then cooled at 110°C, where the transverse stretching ratio is 4 : 1. Transverse stretching temperature is 120℃;

S3.2, heat treatment

The membrane obtained in S3.1 is heat treated to produce a composite polymer film. The thickness of the composite polymer film is 6 μm. The above heat treatment process includes the following stages:

The first stage: the heat treatment temperature is 140℃ and the heat treatment time is 0.5min;

Second stage: The heat treatment temperature is 160°C and the heat treatment time is 0.5 minutes;

The third stage: the heat treatment temperature is 140°C and the heat treatment time is 0.5 minutes.

Composite current collectors are fabricated as follows:

(1) Manufacturing metal conductive layer

The manufactured composite polymer film is placed in a vacuum evaporation chamber, so that the high-purity aluminum wire (purity greater than 99.99%) in the metal evaporation chamber is melted and evaporated at 1300-2000°C, and the evaporated metal atoms pass through the vacuum coating chamber The cooling system is deposited on both surfaces of the composite polymer film to form an aluminum metal conductive layer with a thickness of 1 μm;

(2) Create protective layer

1g of carbon nanotubes was evenly dispersed into 999g of nitrogen methylpyrrolidone (NMP) by ultrasonic dispersion to prepare a coating liquid with a solid content of 0.1wt%, and then the coating liquid was evenly coated through a die coating process. Coated onto the surface of the metal conductive layer, the coating amount is controlled at 90 μm, and finally dried at 100°C.

Example 2

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, the polyester chip A and polyester chip C layers are independently composed of 96% PET resin, 3% nanometer silica, and 0.5% antioxidant. 1222 and 0.5% calcium carbonate.

Example 3

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, the polyester chip A and polyester chip C layers are independently composed of 94% PET resin, 5% nanometer silica, and 0.5% antioxidant. 1222 and 0.5% calcium carbonate.

Example 4

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, the polyester chip A and polyester chip C layers are independently composed of 92% PET resin, 7% nanometer silica, and 0.5% antioxidant. 1222 and 0.5% calcium carbonate.

Example 5

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, the polyester chip A and polyester chip C layers are independently composed of 90% PET resin, 9% nanometer silica, and 0.5% antioxidant. 1222 and 0.5% calcium carbonate.

Example 6

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, the polyester chip A and polyester chip C layers are independently composed of 89% PET resin, 10% nanometer silica, and 0.5% antioxidant. 1222 and 0.5% calcium carbonate.

Example 7

It is basically the same as Example 4, except that the nanooxides in the first and second surface layers are all made of tubular nanosilica (diameter: 25 nm, length: 0.4 μm).

Example 8

It is basically the same as Example 4, except that the nano-oxides in the first and second surface layers are both linear nano-silica (diameter: 10 nm, length: 0.5 μm).

Example 9

It is basically the same as Example 8, except that the nano-oxides in the first and second surface layers are linear nano-alumina (diameter: 10 nm, length: 0.5 μm).

Example 10

It is basically the same as Example 8, except that the nano-oxides in the first and second surface layers are both linear nano-titanium dioxide (diameter: 10 nm, length: 0.5 μm).

Example 11

Basically the same as Example 8, the difference is that in step S1, the polyester chip layer B is made of 99.2% PET resin, 0.3% nano-alumina and 0.5% antioxidant 1222 in terms of mass percentage.

Example 12

Basically the same as Example 8, the difference is that in step S1, the polyester chip layer B is made of 99.0% PET resin, 0.5% nano-alumina and 0.5% antioxidant 1222 in terms of mass percentage.

Example 13

Basically the same as Example 8, the difference is that in step S1, the polyester chip layer B is made of 98.8% PET resin, 0.7% nano-alumina and 0.5% antioxidant 1222 in terms of mass percentage.

Example 14

Basically the same as Example 8, except that in step S1, the polyester chip layer B is made of 98.6% PET resin, 0.9% nano-alumina and 0.5% antioxidant 1222 in terms of mass percentage.

Example 15

Basically the same as Example 8, the difference is that in step S1, the polyester chip layer B is made of 98.5% PET resin, 1.0% nano-alumina and 0.5% antioxidant 1222 in terms of mass percentage.

Example 16

It is basically the same as Example 12, except that the inorganic nanomaterial of the core layer is tubular nanoalumina (diameter: 25 nm, length: 0.4 μm).

Example 17

It is basically the same as Example 12, except that the inorganic nanomaterial of the core layer is linear nano-alumina (diameter: 10 nm, length: 0.5 μm).

Example 18

It is basically the same as Example 17, except that the inorganic nanomaterial of the core layer is a single-walled carbon nanotube (diameter: 5 nm, length: 0.2 μm).

Example 19

It is basically the same as Example 17, except that the inorganic nanomaterial of the core layer is graphene (sheet diameter is 0.2 μm, thickness is 0.8 nm, single layer rate is 80%).

Example 20

It is basically the same as Example 19, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment time is 1 min.

Example 21

It is basically the same as Example 19, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment time is 2 minutes.

Example 22

It is basically the same as Example 19, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment time is 3 minutes.

Example 23

It is basically the same as Example 19, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment time is 5 minutes.

Example 24

It is basically the same as Example 21, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment temperature is 180°C.

Example 25

It is basically the same as Example 21, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment temperature is 200°C.

Example 26

It is basically the same as Example 21, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment temperature is 220°C.

Example 27

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, polyester chips A and polyester chips C are independently composed of 98.8% PET resin, 1% nanometer silica, and 0.1% antioxidant 1222 and 0.1% calcium carbonate.

Example 28

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, polyester chips A and polyester chips C are independently composed of 88% PET resin, 10% nanometer silica, and 1% antioxidant 1222 and 1% calcium carbonate.

Example 29

Basically the same as Example 8, the difference is that in step S1, polyester chips B are made from 99.8% PET resin, 0.1% nano-alumina and 0.1% antioxidant 1222 in terms of mass percentage.

Example 30

Basically the same as Example 8, the difference is that in step S1, polyester chips B are made from 98% PET resin, 1% nano-alumina and 1% antioxidant 1222 in terms of mass percentage.

Comparative example 1

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, the polyester chip A and polyester chip C layers are independently made of 99% PET resin, 0.5% antioxidant 1222 and 0.5% calcium carbonate. Obtained, polyester chip B is made from 99.5% PET resin and 0.5% antioxidant 1222.

Comparative example 2

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, the polyester chip A and polyester chip C layers are independently composed of 98.5% PET resin, 0.5% nanometer silica, and 0.5% antioxidant. 1222 and 0.5% calcium carbonate.

Comparative example 3

Basically the same as Example 1, the difference is that in step S1, in terms of mass percentage, the polyester chip A and polyester chip C layers are independently composed of 87% PET resin, 12% nanometer silica, and 0.5% antioxidant. 1222 and 0.5% calcium carbonate.

Comparative example 4

Basically the same as Example 8, the difference is that in step S1, polyester chips B are made from 99.45% PET resin, 0.05% nano-alumina and 0.5% antioxidant 1222 in terms of mass percentage.

Comparative example 5

Basically the same as Example 8, the difference is that in step S1, polyester chips B are made of 98% PET resin, 1.5% nano-alumina and 0.5% antioxidant 1222 in terms of mass percentage.

Comparative example 6

It is basically the same as Example 19, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment time is 0.1 min.

Comparative example 7

It is basically the same as Example 19, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment time is 6 minutes.

Comparative example 8

It is basically the same as Example 21, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment temperature is 155°C.

Comparative example 9

It is basically the same as Example 21, except that in step S3.2, in the second stage of the heat treatment process, the heat treatment temperature is 225°C.

Test Example 1 Performance test of composite polymer membrane and composite current collector

According to the national standards GB/T 1040.3-2006 and GB/T 10003-2008, the tensile strength, elongation at break and thermal shrinkage of the manufactured composite polymer film and composite current collector were tested;

Test the adhesion between the composite polymer film and the metal conductive layer: bond a layer of Permacel P-94 double-sided tape on a 1mm thick aluminum foil, bond the composite current collector on top of the double-sided tape, and place the composite current collector on the composite collector. The fluid is covered with a layer of ethylene acrylic acid copolymer film (DuPont Nurcel0903, thickness 50 μm), then hot pressed at 1.3×10 ⁵ N/m ² and 120°C for 10 s, cooled to room temperature, and cut into strips of 150 mm×15 mm; Finally, the small strip of ethylene acrylic acid copolymer film of the sample is fixed on the upper clamp of the tensile machine, and the remaining part is fixed on the lower clamp. After being fixed, the two are peeled off at an angle of 180° and a speed of 100mm/min. The peeling force is tested, which is The bonding force between the composite polymer film and the metal conductive layer, the above test results are shown in Tables 1 to 2.

Table 1 Performance test results of composite polymer membranes

Note: MD represents the longitudinal direction of the composite polymer film, TD represents the transverse direction of the composite polymer film, the direction with the longer side length of the composite polymer film is the longitudinal direction, and the direction with the shorter side length of the composite polymer film is the transverse direction. The two directions are perpendicular to each other; the thermal shrinkage rate is the data measured after heating the composite polymer film at 150°C for 30 minutes.

Table 2 Performance test results of composite current collector

Note: MD represents the longitudinal direction of the composite current collector, and TD represents the transverse direction of the composite current collector. The direction with the longer side length of the composite current collector is the longitudinal direction, and the direction with the shorter side length of the composite current collector is the transverse direction. The two directions are mutually exclusive. Vertical; thermal shrinkage data measured after heating the current collector at 150°C for 30 minutes.

As can be seen from Tables 1 to 2, Examples 1 to 6 investigated the effect of changes in the nano-silica content in surface layer one and surface layer two on the performance of the composite polymer film; Examples 4, 7 and 8 examined the effects of the changes in the nanosilica content in surface layer one and surface layer two on the performance of the composite polymer membrane. The influence of the shape of silica in surface layer 1 and surface layer 2 on the performance of composite polymer membranes; Examples 8 to 10 examined the influence of the types of nano-oxides in surface layer 1 and surface layer 2 on the properties of composite polymer membranes; Examples 8 and 10 Examples 11-15 examined the effect of the content of nano-alumina in the core layer on the performance of the composite polymer membrane; Examples 12 and 16-17 examined the effect of the shape of the nano-alumina in the core layer on the performance of the composite polymer membrane. Effect; Examples 17 to 19 examined the impact of the types of inorganic nanomaterials in the core layer on the performance of the composite polymer membrane; Examples 19 to 23 examined the impact of the heat treatment time in the second stage of the heat treatment process on the performance of the composite polymer membrane. Increasing the heat treatment time in the second stage can increase the crystallinity of the composite polymer film, thereby increasing the tensile strength of the composite polymer film while reducing the thermal shrinkage and elongation at break.

Example 21 and Examples 24-25 examined the effect of the heat treatment temperature in the second stage of the heat treatment process on the performance of the composite polymer film. Increasing the heat treatment temperature in the second stage can increase the crystallinity of the composite polymer film, making the composite polymer The tensile strength of the film increases while the thermal shrinkage and elongation at break decrease.

Compared with Examples 1 to 6 and Examples 27 to 28, the tensile strength of the composite polymer films produced in Comparative Examples 1 to 2 was smaller in both MD and TD directions, and the fracture in both MD and TD directions was smaller. The elongation and thermal shrinkage are large, and the bonding force between the composite polymer film produced in Comparative Examples 1 and 2 and the metal conductive layer is small, indicating the addition of PET resin in the first and second surface layers of Comparative Examples 1 and 2. Too low or too high amounts are not conducive to improving the surface adhesion, mechanical strength and heat resistance of the composite polymer film.

Compared with Examples 1 to 6 and Examples 27 to 28, the composite polymer film and composite current collector produced in Comparative Example 3 have smaller thermal shrinkage rates in both MD and TD directions, indicating that they have better heat resistance. However, its tensile strength in both MD and TD directions is significantly lower, indicating that its mechanical strength is poor.

Although the adhesive force of Comparative Examples 4 to 5 and the composite polymer film and metal conductive layer produced in Examples 11 to 15 and Example 30 are all 4.5 N/cm, compared with Examples 11 to 15 and Example 30 , the tensile strengths of the composite polymer films and composite current collectors produced in Comparative Examples 4 to 5 are significantly lower in both MD and TD directions, indicating that the mechanical strength of the composite polymer films and composite current collectors produced in Comparative Examples 4 to 5 is Poor.

Although the bonding force between the composite polymer film and the metal conductive layer produced in Comparative Example 6 and Examples 19-23 is 4.5 N/cm, compared with Examples 19-23, the composite polymer film produced in Comparative Example 6 has The tensile strength in the MD and TD directions of the composite current collector and the composite current collector are relatively small, and the elongation at break and thermal shrinkage are relatively high, indicating that the composite polymer film and composite current collector manufactured in Comparative Example 6 have poor mechanical strength and durability. Poor thermal performance.

Although the adhesive force between the composite polymer film and the metal conductive layer produced in Comparative Examples 8 to 9 is equal to that of Example 21 and Examples 24 to 26, the composite polymer film and composite current collector produced in Comparative Examples 8 to 9 are in MD. The tensile strength in the and TD directions is relatively small, and the elongation at break and thermal shrinkage are relatively high, indicating that the composite polymer films and composite current collectors produced in Comparative Examples 8 to 9 have poor mechanical strength.

It can be seen that the surface adhesion, mechanical strength and heat resistance of the composite polymer film of the present application are significantly improved.

The technical features of the above-described embodiments can be combined in any way. To simplify the description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, All should be considered to be within the scope of this manual.

The above-described embodiments only express several implementation modes of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all fall within the protection scope of the present application. Therefore, the scope of protection of this patent application should be determined by the appended claims.

Claims

A composite polymer film, characterized in that the composite polymer film includes a core layer, a surface layer one and a surface layer two, and the core layer is located between the surface layer one and the surface layer two;

In terms of mass percentage, the raw materials for manufacturing the core layer include: 98% to 99.8% polyester materials, 0.1% to 1% inorganic nanomaterials and 0.1% to 1% antioxidants. The surface layer one and the surface layer two are The manufacturing raw materials each independently include: 88% to 98.8% polyester material, 1% to 10% nano oxide and 0.2% to 2% additives.
The composite polymer film according to claim 1, wherein the nano-oxide includes aluminum oxide, silicon dioxide, titanium dioxide, zinc oxide, copper oxide, magnesium oxide, ferric oxide, ferric oxide, One or more of zirconium dioxide and tin dioxide.
The composite polymer film according to any one of claims 1 to 2, wherein the inorganic nanomaterial includes one of nanooxide, graphene, graphene oxide, carbon nanotube and carbon nanofiber, or Various.
The composite polymer film according to any one of claims 1 to 3, wherein the polyester material includes polyethylene terephthalate, polyethylene 2,6-naphthalate, Polybutylene terephthalate, poly1,4-cyclohexanedimethanol terephthalate, polyethylene terephthalate-1,4-cyclohexanedimethanol, poly2, Trimethylene 6-naphthalate, polytrimethylene terephthalate, polybutylene 2,6-naphthalate, polybutylene 2,5-furandicarboxylate, polybutylene adipate terephthalate One or more of glycol esters, polyarylates and their derivatives.
The composite polymer film according to any one of claims 1 to 4, wherein the additives include antioxidants and slip agents;

Optionally, the antioxidant includes one or more of phosphonate and bisphenol A phosphite;

Optionally, the slip agent includes one or more of calcium carbonate, talc, kaolin, diatomaceous earth, siloxane, clay, mica, aluminum silicate, potassium phosphate, barium sulfate and acrylate.
The composite polymer film according to any one of claims 1 to 5, wherein the thickness of the composite polymer film is 1 to 50 μm.
The manufacturing method of a composite polymer film according to any one of claims 1 to 6, characterized in that it includes the following steps:

S1. Manufacture polyester slices A, polyester slices B and polyester slices C respectively, wherein, in terms of mass percentage, the polyester slices A and polyester slices C are each independently made of 88% to 98.8% polyester material. , 1% to 10% nano oxide and 0.2% to 2% additives. The polyester slice B is made of 98% to 99.8% polyester material, 0.1% to 1% inorganic nanomaterials and 0.1% to 1% Made from antioxidants;

S2. The polyester slice A, the polyester slice B and the polyester slice C are melted and extruded to obtain a molten polyester material having a core layer, a surface layer one and a surface layer two. The core layer is located at Between the surface layer one and the surface layer two;

S3. Perform molding treatment and heat treatment on the molten polyester material in sequence.
The manufacturing method of composite polymer membrane according to claim 7, characterized in that the heat treatment process of step S3 includes the following steps:

The first stage: the heat treatment temperature is 130~160℃, and the heat treatment time is 0.5~2min;

Second stage: The heat treatment temperature is 160~220℃, and the heat treatment time is 0.5~5min;

The third stage: the heat treatment temperature is 130~160℃, and the heat treatment time is 0.5~2min.
A metallized composite polymer film, characterized in that it includes a composite polymer film and a metal conductive layer. The composite polymer film adopts the composite polymer film described in any one of claims 1 to 6 or claims 7 to 6. 8. The composite polymer film produced by the manufacturing method according to any one of the above, wherein the metal conductive layer is provided on at least one surface of the composite polymer film;

Optionally, the material of the metal conductive layer includes one or more of copper, copper alloy, aluminum, aluminum alloy, nickel, nickel alloy, titanium and silver.
The metallized composite polymer film according to claim 9, wherein the thickness of the metal conductive layer is 20-2000 nm.
A composite current collector, characterized by comprising the metallized composite polymer film according to any one of claims 9 to 10.
The composite current collector according to claim 11, further comprising a protective layer located on the metal conductive layer of the metallized composite polymer film.
The composite current collector according to claim 12, wherein the protective layer includes nickel, chromium, nickel-based alloy, copper-based alloy, copper oxide, aluminum oxide, nickel oxide, chromium oxide, cobalt oxide, graphite, carbon One or more of black, acetylene black, Ketjen black, carbon nanometer quantum dots, carbon nanotubes, carbon nanofibers and graphene.
The composite current collector according to any one of claims 12 to 13, wherein the thickness of the protective layer is 10 to 150 nm.
An electrode pole piece, characterized by including the composite current collector according to any one of claims 11 to 14.
A battery, characterized by comprising the electrode pole piece according to claim 15.
An electronic device, characterized by comprising the battery according to claim 16.