WO2022041445A1

WO2022041445A1 - Method for preparing conductive film, current collection and transmission material, and energy storage apparatus

Info

Publication number: WO2022041445A1
Application number: PCT/CN2020/123845
Authority: WO
Inventors: 贾孟
Original assignee: 昆山鑫美源电子科技有限公司
Priority date: 2020-08-22
Filing date: 2020-10-27
Publication date: 2022-03-03
Also published as: CN114075654B; CN114075654A

Abstract

A method for preparing a conductive film, a current collection and transmission material, and an energy storage apparatus, the preparation method comprising the following steps: S1, using a vacuum plating device to plate one surface of a film substrate (30), so as to form a first metal plating (10); S2, forming a second metal plating (20) on an outer surface of the first metal plating (10) by means of a water plating apparatus, thereby forming a single-sided metal film (40); S3, using a coating compounding machine to single-sidedly coat a PI material (50) on a metal layer surface of the single-sided metal film (40), and then preliminarily drying the PE material (50) on the single-sided metal film (40) by means of an oven (406); S4, pressing, shaping and cooling a metal layer surface of another single-sided metal film (40) obtained in step S2 and the surface of the PI material (50) in step S3; and S5, passing through high-temperature curing to obtain a multilayer composite metal material, and stripping the film substrate (30) of upper and lower surfaces of the composite multilayer metal material, so as to form a conductive film (70). The method may ease limitations on outer film substrate thickness, avoid the emergence of holes, and improve product yield.

Description

Preparation method of conductive film, current collecting and transporting material and energy storage device

technical field

The invention relates to a preparation method of a functional thin film of a multi-layer composite structure, and more specifically, the present invention relates to a preparation method of a conductive thin film, a current collection and transmission material and an energy storage device.

Background technique

Metal is plated on the film to obtain a metal-coated film with certain functions. This metal-coated film is widely used in various fields. In recent years, copper, aluminum and other metals are plated on ultra-thin films for the development of the battery field. very quickly. To achieve coating a layer of metal on the film, the main methods include evaporation coating, sputtering coating, etc. Evaporation coating mainly uses a heat source to heat the evaporation boat or crucible, so that the evaporation material located in the evaporation boat or crucible is melted and evaporated. Under vacuum conditions, the vapor deposition material leaves the crucible in the form of atoms or ions, and settles on the surface of the substrate to form a thin film through the film-forming process (scattered-island-like structure-vagus structure-layered growth). The sputtering coating mainly uses electrons or high-energy lasers to bombard the target, so that the surface components are sputtered out in the form of atomic groups or ions, and finally deposited on the surface of the substrate, go through the film-forming process, and finally form a thin film. The generation process in the prior art usually combines several coating methods to obtain a stable process with certain characteristics. A layer of metal film is sputtered and then water-plated to increase the thickness of the metal layer.

In order to meet the thickness requirements of the conductive film, there are specific requirements for the thickness of the base film, which makes it necessary to limit the thickness of the base film when producing the conductive film roll, and the thickness of the base film can only be within a certain range. Not too thin or too thick.

In addition, when the evaporation coating is performed, the material is easily heated unevenly and the local temperature is too high. When the base film is encountered, the base film will be ironed through to form holes, thereby affecting the product qualification rate.

SUMMARY OF THE INVENTION

In order to overcome the deficiencies of the prior art, the present invention provides a preparation method of a conductive film, which relaxes the restriction on the thickness of the outer film substrate, avoids the phenomenon of holes, and improves the yield of the product.

The technical scheme adopted by the present invention to solve the technical problem is: a preparation method of a conductive film, and its improvement lies in that the preparation method comprises the following steps:

S1. Use vacuum coating equipment to coat one surface of the thin film substrate to form a first metal coating with a thickness of 50-200 nm;

S2, forming a second metal plating layer with a thickness of 600-900 nm on the outer surface of the first metal plating layer by a water plating device, thereby forming a single-sided metal film;

S3. Use a coating compound machine to coat the PI material with a thickness of 2-4 μm on the surface of the metal layer of the single-sided metal film on one side, and then preliminarily dry the PI material on the single-sided metal film through an oven;

S4, press the surface of the metal layer of the other single-sided metal film obtained in step S2 with the surface of the PI material in step S3 to form and cool;

S5. A multi-layer composite metal material is made by high temperature curing, and the film substrates on the upper and lower surfaces of the composite multi-layer metal material are peeled off to form a finished conductive film.

Further, in the step S1, the film substrate includes but is not limited to PP film, PE film or PET film.

Further, the thickness of the film substrate is 12-20 μm, and the thickness of the conductive film is 4-6 μm.

Further, in the step S1, the vacuum coating equipment includes but is not limited to vacuum evaporation coating equipment or magnetron sputtering coating equipment.

Further, in the step S2, the water plating device is an alkaline water plating device or an acid water plating device.

Further, the first metal plating layer and the second metal plating layer are both copper plating layers.

Further, in the step S3, the temperature in the oven is 70-90°C, and the drying time is 1-2min.

Further, in the step S5, the high temperature curing temperature is 50-60° C., and the time is 14-18 h.

Further, in the step S5, a peeling machine is used to realize the peeling of the film substrate.

Further, before step S1, it also includes step S0: coating a layer of release agent with a thickness of 0.3-1um on both sides of the film substrate, so that the film substrate and the functional film can be effectively peeled off in subsequent steps.

Further, the single-sided resistance of the conductive film is within 20mΩ.

The present invention also provides a current collecting and transporting material, which is improved in that: the current collecting and transporting material comprises the conductive thin film described in any one of the above.

The present invention also provides an energy storage device, comprising a cathode electrode sheet, an anode electrode sheet, a separator, an electrolyte and a packaging shell, the improvement of which is that the cathode electrode sheet uses the above-mentioned current collection and transmission material.

The beneficial effects of the invention are as follows: the restriction on the thickness of the outer film substrate is relaxed, the defect that the film substrate cannot be too thin or too thick in the prior art is avoided, and at the same time, the evaporation of the film substrate in the prior art route is avoided. Bubbles and holes are prone to occur during the coating process; the use of PI material to replace the original formed film reduces the production energy consumption and material cost, and can greatly improve the quality of the product under the premise of meeting the conductivity requirements. Rate.

Description of drawings

FIG. 1 is a method flow chart of a method for preparing a conductive thin film according to the present invention.

FIG. 2 is a structural diagram of a product formed in step S1 of a method for preparing a conductive thin film of the present invention.

FIG. 3 is a structural diagram of a product formed in step S2 of a method for preparing a conductive thin film of the present invention.

FIG. 4 is a working principle diagram of a coating compound machine in steps S3 and S4 of a method for preparing a conductive film of the present invention.

FIG. 5 is a schematic structural diagram of a coating compound machine used in step S4 of a method for preparing a conductive film of the present invention.

FIG. 6 is a structural diagram of a product formed in step S5 of a method for preparing a conductive thin film of the present invention.

FIG. 7 is a schematic structural diagram of peeling off the film substrate in step S5 of a method for preparing a conductive film of the present invention.

FIG. 8 is a schematic structural diagram of the metal thin film formed in step S5 of a method for preparing a conductive thin film of the present invention.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

The concept, specific structure and technical effects of the present invention will be clearly and completely described below with reference to the embodiments and accompanying drawings, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative efforts are all within the scope of The scope of protection of the present invention. In addition, all the coupling/connection relationships involved in the patent do not mean that the components are directly connected, but refer to a better coupling structure by adding or reducing coupling accessories according to the specific implementation. Various technical features in the present invention can be combined interactively on the premise of not contradicting each other.

Example 1

Referring to FIG. 1 , the present invention discloses a method for preparing a conductive film, through which the preparation of the conductive film is realized. Specifically, in this embodiment, the method includes the following steps:

S0: apply a layer of release agent with a thickness of 0.3-1um on both sides of the film substrate;

S1. Use vacuum coating equipment to coat one surface of the thin film substrate 30 to form a first metal coating layer 10 with a thickness of 50 nm; in this embodiment, the thin film substrate 30 is a PET film with a thickness of 12 μm, and the vacuum coating equipment is a vacuum coating Evaporation coating equipment, as shown in FIG. 2 , the first metal coating layer 10 is formed on one surface of the film substrate 30;

S2. Using a water plating device, a second metal plating layer 20 with a thickness of 900 nm is formed on the outer surface of the first metal plating layer 10, thereby forming a single-sided metal film 40; in this embodiment, the water plating device is alkaline water plating equipment, and the first metal plating layer 10 and the second metal plating layer 20 are both copper plating layers, as shown in FIG. 3 , the second metal plating layer 20 is formed on the other side of the first metal plating layer 10;

S3. Use a coating compound machine to coat 3 μm PI material 50 on the surface of the metal layer of the single-sided metal film on one side, and then preliminarily dry the PI material 50 on the single-sided metal film through an oven; in this embodiment , the temperature in the oven is 70 ℃, and the drying time is 2min. During the drying process, care should be taken to avoid the loss of adhesion caused by baking the PI material 50 until it is completely dry;

S4, press the surface of the metal layer of the other single-sided metal film obtained in step S2 with the surface of the PI material 50 in step S3 to form and cool;

In this embodiment, as shown in FIG. 4 , the two single-sided metal films 40 are compounded by the first compounding roll 401 and the second compounding roll 402 respectively, and the single-sided metal film 40 on the left in FIG. 4 is The PI material 50 is loaded by the feeding device 403, and the PI material 50 is coated on the upper surface of the single-sided metal film 40, and then dried by the oven 406, and then passed through the first composite roller 401 and the second composite roller. 402 realizes the compounding of the two single-sided metal films 40, and sandwiches the PI material 50 between the two single-sided metal films 40; and then realizes the cooling of the finished film after compounding through the cooling roller 404, and realizes the cooling of the finished film through the take-up roller 405. Receiving materials; as shown in FIG. 6 , which is a schematic view of the structure of the finished film, the first metal coating and the second metal coating located above the PI material 50 form an upper metal layer 501, and the first metal coating and the second metal coating located below the PI material 50 form an upper metal layer 501. Two metal plating layers form a lower metal layer 502;

S5. A multi-layer composite metal material is prepared by high temperature curing, and the film substrate 30 on the upper and lower surfaces of the composite multi-layer metal material is peeled off to form a 5 μm conductive film, and the single-sided resistance of the conductive film is within 20 mΩ at this time; In this embodiment, the high temperature curing temperature is 50°C and the time is 18h.

As shown in FIG. 7 , the peeling machine 60 is used to peel off the film substrate 30, and the discharging roller 601 is used to realize the discharging of the finished film. , The lower two layers of the film substrate 30 are peeled off from the conductive film 70 , as shown in FIG. 8 , which is a schematic structural diagram of the formed conductive film 70 .

Further, in this embodiment, based on the above-mentioned conductive film, the present invention further provides a current collection and transmission material, and the current collection and transmission material includes the above-mentioned conductive film.

Further, the present invention also discloses an energy storage device, comprising a cathode electrode sheet, an anode electrode sheet, a separator, an electrolyte and a packaging case, and the cathode electrode sheet uses the above-mentioned current collection and transmission material.

In the above-mentioned embodiments, as shown in FIG. 5 , the present invention provides a specific embodiment of the coating compound machine. The coating compound machine is also known as a dry compound machine, which includes a first unwinding device 1 , Coating device 2, oven 3, second unwinding device 4, compounding device 5, winding device 6 and cooling roller 7. First, install the substrate in step S3 according to the guide rollers along the routing direction of the substrate of the first unwinding device 1 and the coating device 2. At the same time, the PI material 50 is formulated into an adhesive according to the ratio, and the oven is started. The heating system of 3, after reaching the corresponding preset temperature, turn on the transmission motor, and the substrate after step S3 is driven by the guide roller and the motor, and passes through the coating device 2 along the wiring direction, and is coated with 3-4um PI material 50, the coated base material is preliminarily dried through the drying tunnel part of the oven 3 along the routing direction according to the guide roller, and when the base material is in the drying tunnel part, unwind on the second unwinding device Another roll of base material that has undergone the water-plating coating process, the base material that has been preliminarily dried in the oven and another roll of base material that has undergone the water-plating process arrive at the compounding device 5 at the same time for compounding, and the compounded base material is cooled by the cooling roller 7, Finally, it reaches the winding device 6 for winding to obtain a multi-layer metal composite material. Since the coating compound machine is a relatively mature device in the prior art, its structure will not be explained in detail in this embodiment and the following.

The preparation method of the above-mentioned conductive film, in the selection of materials, relaxes the restriction on the thickness of the outer film base material 30, avoids the defect that the film base material 30 cannot be too thin or too thick in the prior art, and at the same time, avoids the prior art. In the route, the film substrate 30 is prone to the phenomenon of bubbles and holes during the evaporation coating process; the use of PI material 50 to replace the original formed film reduces the production energy consumption and material cost under the premise of meeting the electrical conductivity requirements, and To a large extent, the quality of the product can be improved. In addition, the preparation method greatly reduces the specification requirements of the evaporation equipment and the water electroplating equipment, reduces the investment in fixed assets, and thus greatly reduces the total product cost as a whole. The peeled outer layer film substrate 30 can be recycled and reused after being processed.

Example 2

S1. Use vacuum coating equipment to coat one surface of the thin film substrate 30 to form a first metal coating layer 10 with a thickness of 200 nm; in this embodiment, the thin film substrate 30 is a PET film with a thickness of 20 μm, and the vacuum coating equipment is a magnetic Control sputtering coating equipment, as shown in FIG. 2 , the first metal coating layer 10 is formed on one surface of the film substrate 30;

S2. A second metal coating layer 20 with a thickness of 600 nm is formed on the outer surface of the first metal coating layer 10 by a water plating device, thereby forming a single-sided metal film 40; in this embodiment, the water plating device is an acid water plating device, And the first metal coating layer 10 and the second metal coating layer 20 are both copper coating layers, as shown in FIG. 3 , the second metal coating layer 20 is formed on the other side of the first metal coating layer 10;

S3. Use a coating compound machine to coat the PI material 50 of 4 μm on the surface of the metal layer of the single-sided metal film 40 on one side, and then preliminarily dry the PI material on the single-sided metal film through an oven; in this embodiment , the temperature in the oven is 90 ℃, and the drying time is 1min. During the drying process, care should be taken to avoid the loss of adhesion caused by baking the PI material 50 until it is completely dry;

S4, pressing the surface of the metal layer of the other single-sided metal film 40 obtained in step S2 with the surface of the PI material 50 in step S3 to shape and cool;

In this embodiment, as shown in FIG. 4 , the two single-sided metal films 40 are compounded by the first compounding roll 401 and the second compounding roll 402 respectively, and the single-sided metal film 40 on the left in FIG. 4 is The feeding of the PI material 50 is realized by the feeding device, and the PI material 50 is coated on the upper surface of the single-sided metal film 40, and then dried in an oven, and then realized by the first composite roller 401 and the second composite roller 402. For the compounding of two single-sided metal films 40, the PI material 50 is sandwiched between the two single-sided metal films 40; the cooling of the finished film after the compounding is realized by cooling rollers, and the collection of finished films is realized by a receiving roller; such as As shown in FIG. 6 , which is a schematic structural diagram of the finished film, the first metal coating and the second metal coating above the PI material 50 form an upper metal layer, and the first metal coating and the second metal coating below the PI material 50 form a lower metal layer metal layer;

S5. A multi-layer composite metal material is made by high temperature curing, and the film substrate 30 on the upper and lower surfaces of the composite multi-layer metal material is peeled off to form a 6 μm conductive film. At this time, the single-sided resistance of the conductive film is within 20mΩ, In this embodiment, the high temperature curing temperature is 60°C and the time is 14h.

As shown in FIG. 7 , the peeling machine 60 is used to peel off the film substrate 30, and the discharging roller is used to realize the discharging of the finished film, and then through the cooperation of the upper and lower peeling rollers, the upper and lower The layered film substrate 30 is peeled off from the conductive film, as shown in FIG. 8 , which is a schematic structural diagram of the formed conductive film.

Example 3

S1. Use vacuum coating equipment to coat one surface of the thin film substrate 30 to form a first metal coating layer 10 of 150 nm; in this embodiment, the thin film substrate 30 is a PET film with a thickness of 8 μm, and the vacuum coating equipment is a vacuum coating Evaporation coating equipment, as shown in FIG. 2 , the first metal coating layer 10 is formed on one surface of the film substrate 30;

S2. Using a water plating device, form a second metal plating layer 20 with a thickness of 800 nm on the outer surface of the first metal plating layer 10, thereby forming a single-sided metal film 40; in this embodiment, the water plating device is an alkaline water plating device , and the first metal plating layer 10 and the second metal plating layer 20 are both copper plating layers, as shown in FIG. 3 , the second metal plating layer 20 is formed on the other side of the first metal plating layer 10;

S3. Use a coating compound machine to coat the PI material 50 of 3 μm on the surface of the metal layer of the single-sided metal film 40 on one side, and then preliminarily dry the PI material on the single-sided metal film through an oven; , the temperature in the oven is 80 ℃, and the drying time is 1.5min. During the drying process, care should be taken to avoid the loss of adhesion caused by baking the PI material 50 until it is completely dry;

S5. A multi-layer composite metal material is made by high temperature curing, and the film substrate 30 on the upper and lower surfaces of the composite multi-layer metal material is peeled off to form a conductive film of 5 μm. At this time, the single-sided resistance of the conductive film is within 20mΩ, In this embodiment, the high temperature curing temperature is 55°C and the time is 16h.

Example 4

This embodiment provides a method for preparing a conductive film, through which the conductive film is prepared. The process steps of this embodiment are exactly the same as those of Embodiment 1, and the only difference is that the thickness of the film substrate 30 is 20 μm The thickness of the first metal coating layer 10 is 100 nm, the thickness of the second metal coating layer 20 is 800 nm, the thickness of the PI material is 2 μm, and the thickness of the formed conductive film is 4 μm.

In any of the above-mentioned embodiments, when the vacuum coating equipment is a vacuum evaporation coating equipment or a magnetron sputtering coating equipment, when the water coating device is an alkaline water coating equipment or an acidic water coating equipment, neither the vacuum coating equipment nor the The water plating device is explained in detail. The reason is that the vacuum coating equipment and the water plating device are very mature technologies in the prior art, and the vacuum coating equipment and the water plating device themselves have not been proposed in any of the above-mentioned embodiments of the present invention. Improvement, the forming of the first metal coating layer and the second metal coating layer is realized only by means of mature technology in the prior art.

The present invention relaxes the restriction on the thickness of the outer film substrate 30, and the film substrate 30 of 8-20 μm can be selected to avoid the defect that the film substrate 30 cannot be too thin or too thick in the prior art, and at the same time, the original film substrate 30 is avoided. In the technical route, the film substrate 30 is prone to the phenomenon of bubbles and holes during the evaporation coating process; the PI material 50 is used to replace the original formed film, and on the premise of meeting the electrical conductivity requirements, the production energy consumption and material cost are reduced. And it can greatly improve the quality of the product.

The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the described embodiments, and those skilled in the art can also make various equivalent deformations or replacements on the premise that does not violate the spirit of the present invention , these equivalent modifications or substitutions are all included within the scope defined by the claims of the present application.

Claims

A preparation method of a conductive film, characterized in that the preparation method comprises the following steps:

S1. Use vacuum coating equipment to coat one surface of the thin film substrate to form a first metal coating with a thickness of 50-200 nm;

S2, forming a second metal plating layer with a thickness of 600-900 nm on the outer surface of the first metal plating layer by a water plating device, thereby forming a single-sided metal film;

S3. Use a coating compound machine to coat the PI material with a thickness of 2-4 μm on the surface of the metal layer of the single-sided metal film on one side, and then preliminarily dry the PI material on the single-sided metal film through an oven;

S4, press the surface of the metal layer of the other single-sided metal film obtained in step S2 with the surface of the PI material in step S3 to form and cool;

S5. A multi-layer composite metal material is made by high temperature curing, and the film substrates on the upper and lower surfaces of the composite multi-layer metal material are peeled off to form a finished conductive film.
The method for preparing a conductive film according to claim 1, wherein in the step S1, the film substrate includes but is not limited to PP film, PE film or PET film.
The method for preparing a conductive film according to claim 1 or 2, wherein the thickness of the film substrate is 8-20 μm, and the thickness of the conductive film is 4-6 μm.
The method for preparing a conductive thin film according to claim 1, wherein in the step S1, the vacuum coating equipment includes but is not limited to vacuum evaporation coating equipment or magnetron sputtering coating equipment.
The method for preparing a conductive film according to claim 1, wherein in the step S2, the water plating device is an alkaline water plating device or an acid water plating device.
The method for preparing a conductive film according to claim 1, wherein the first metal plating layer and the second metal plating layer are both copper plating layers.
The method for preparing a conductive thin film according to claim 1, wherein in the step S3, the temperature in the oven is 70-90°C, and the drying time is 1-2min.
The method for preparing a conductive film according to claim 1, characterized in that: in the step S5, the high temperature curing temperature is 50-60°C, and the time is 14-18h.
The method for preparing a conductive film according to claim 1, wherein in the step S5, a peeling machine is used to peel off the film substrate.
The method for preparing a conductive film according to claim 1, wherein the single-sided square resistance of the conductive film is within 20mΩ.
A current collecting and transporting material, characterized in that it comprises the conductive film described in any one of claims 1-10.
An energy storage device, comprising a cathode pole piece, an anode pole piece, a separator, an electrolyte and a packaging shell, characterized in that: the cathode pole piece uses the current collection and transmission material according to claim 11 .