KR102135851B1 - Current collector for electrodes and method for producing the same - Google Patents

Abstract

The current collector for an electrode according to an embodiment of the present invention includes a polymer film; A metal piece provided on at least one surface of the upper and lower surfaces of the polymer film; An adhesive layer provided between the polymer film and the metal piece; A conductive material formed on surfaces of the polymer film and the metal piece; And an electrode active material layer formed on the surface of the conductive material, wherein the metal piece may be provided on the edge of the polymer film but protrude from the edge of the polymer film.

Description

CURRENT COLLECTOR FOR ELECTRODES AND METHOD FOR PRODUCING THE SAME

The present invention relates to a current collector for an electrode and a method of manufacturing the same, and more specifically, by not using a metal foil, the weight of the electrode can be reduced, the thickness of the electrode assembly can be reduced, and the energy density can be increased. It relates to a current collector for an electrode and a method of manufacturing the same.

As technology development and demand for mobile devices increase, the demand for secondary batteries as an energy source is rapidly increasing, and lithium secondary batteries exhibiting high energy density and operating potential among such secondary batteries and low self-discharge rate are commercialized.

The lithium metal secondary battery is the first commercially available secondary battery, and uses lithium metal as a negative electrode. However, the lithium metal secondary battery is due to the lithium resin formed on the surface of the lithium metal negative electrode, the cell volume expansion, gradual reduction in capacity and energy density, short-circuit occurrence due to dendritic continuous growth, cycle life reduction and cell stability problems (explosion and Ignition), and production was stopped only a few years after being commercialized. Thus, instead of lithium metal, a carbon-based negative electrode that is more stable and capable of stably storing lithium in an ionic state in a lattice or an empty space was used, and commercialization and dissemination of a full-scale lithium secondary battery proceeded due to the use of the carbon-based negative electrode.

Until now, lithium secondary batteries are mainly composed of carbon-based or non-carbon-based anode materials, and most anode materials are carbon-based (graphite, hard carbon, soft carbon, etc.) and non-carbon-based (silicon, tin, titanium oxide, etc.) materials. Is focused on.

On the other hand, in recent years, as portable electronic devices and information communication devices have been miniaturized, the use of lithium secondary batteries as a compact power system for driving them has been greatly anticipated.

Moreover, in recent years, development and research on polymer electronic devices and devices using advantages such as flexibility, low cost, and ease of manufacture have been actively conducted. Therefore, in order to use it in a miniaturized device, it is necessary to reduce the thickness or weight of the battery while maintaining the energy density or performance of the lithium secondary battery.

In addition, even if the thickness or weight of the lithium secondary battery is reduced, it is necessary to increase safety and energy density of the lithium secondary battery by blocking or destroying a current path when an internal short circuit occurs.

In order to solve the above problems, the applicant has proposed the present invention.

Korean Patent Publication No. 10-2018-0037898 (April 13, 2018)

The present invention has been proposed to solve the above problems, and provides a current collector for an electrode and a method of manufacturing the same that can reduce the thickness compared to a current collector made of a metal foil.

In addition, the present invention provides a current collector for an electrode that can reduce weight than a current collector made of a metal foil, and a method for manufacturing the same.

In addition, the present invention provides a current collector for an electrode and a method of manufacturing the same that can lower a short circuit current when an internal short circuit occurs because it has a resistance value greater than that of a metal foil current collector.

In addition, the present invention provides an electrode current collector and a method of manufacturing the same, which can increase the energy density of the secondary battery, increase the production efficiency of the electrode current collector, and reduce the discarded electrode material.

The current collector for an electrode according to an embodiment of the present invention for achieving the above object, a polymer film; A metal piece provided on at least one surface of the upper and lower surfaces of the polymer film; An adhesive layer provided between the polymer film and the metal piece; A conductive material formed on surfaces of the polymer film and the metal piece; And an electrode active material layer formed on the surface of the conductive material, wherein the metal piece may be provided on the edge of the polymer film but protrude from the edge of the polymer film.

The current collector for an electrode according to another embodiment of the present invention, a polymer film; A metal piece provided on at least one surface of the upper and lower surfaces of the polymer film; An adhesive layer provided between the polymer film and the metal piece; A conductive material formed on surfaces of the polymer film and the metal piece; And an electrode active material layer formed on the surface of the conductive material. The metal piece may be provided to protrude from the edge of the hole formed in the polymer film.

On the other hand, according to another field of the invention, an embodiment of the present invention, preparing the polymer film in the form of a strip; Bonding the metal piece to at least one of both ends in the width direction of the polymer film; Coating the conductive material to cover the surface of the polymer film and the metal piece; Coating the electrode active material layer on the surface of the conductive material except for the portion where the metal piece is located; And obtaining the current collector for the electrode by punching or cutting along the shape of the current collector for the electrode while transferring the polymer film in the loading direction.

In the step of adhering the metal piece, the metal piece may be positioned on at least one surface of the upper and lower surfaces of the polymer film so that it protrudes from both ends in the width direction of the polymer film.

In the step of bonding the metal pieces, the adhesive layer may be provided between the metal pieces facing each other and the polymer film.

In the step of obtaining the current collector for the electrode, the electrode portion of the current collector for electrodes is formed by punching or being cut at a portion coated with the electrode active material layer, and the tab portion of the current collector for electrodes is punched at a portion where the metal piece is located or It can be cut and formed.

In the step of obtaining the current collector for the electrode, the current collector for the electrode may be punched or cut at both sides of the reference line so as to be symmetric with respect to a reference line passing through the center of both ends in the longitudinal direction of the polymer film.

On the other hand, according to another field of the invention, another embodiment of the present invention, the step of providing the polymer film in the form of a strip; Forming a plurality of holes in the polymer film in a direction orthogonal to the length direction of the polymer film or a width direction of the polymer film; Bonding the metal piece to the polymer film in a direction orthogonal to the longitudinal direction of the polymer film or a width direction of the polymer film to cover the hole; Coating the conductive material to cover the surface of the polymer film and the metal piece; Coating the electrode active material layer on the surface of the conductive material except for the portion where the metal piece is located; And obtaining the current collector for the electrode by punching or cutting along the shape of the current collector for the electrode while transferring the polymer film in the loading direction.

In the step of forming a plurality of holes in the polymer film, the holes are formed in a plurality of holes at the same shape and the same interval in the direction orthogonal to the longitudinal direction of the polymer film or the width direction of the polymer film to form a single hole set, , The hole set may be formed in plural along the longitudinal direction of the polymer film.

In the step of adhering the metal piece, the metal piece has a size sufficient to completely or partially cover the hole and is provided in plural to correspond to the hole set, and the adhesive layer is provided between the metal piece and the polymer film facing each other. Can be.

In the step of obtaining the current collector for the electrode, the electrode part of the current collector for the electrode is formed by punching or being cut at a portion coated with the electrode active material layer, and the tab part of the current collector for the electrode is simultaneously positioned with the metal piece and the hole It can be formed by being punched or cut in parts.

In the step of obtaining the current collector for the electrode, the current collector for the electrode is symmetrical with respect to a reference line passing in the direction parallel to the length direction of the metal piece between the two metal pieces facing each other at a relatively long distance. It may be formed by being punched or cut at both sides of the reference line.

The current collector for an electrode according to the present invention and its manufacturing method use a polymer film made of a non-conductor instead of a metal foil to reduce the weight of the current collector and the battery.

In addition, the current collector for an electrode according to the present invention and its manufacturing method can reduce the thickness of a current collector made of a metal foil because a conductive material is coated or formed on a surface of a polymer film instead of using a metal foil.

In addition, the current collector for an electrode according to the present invention and a method for manufacturing the same have a resistance value greater than that of a metal foil current collector, and also because current flow may be interrupted by damage to the polymer film, short circuit current when an internal short circuit occurs And can improve the safety of the battery.

In addition, the current collector for an electrode according to the present invention and its manufacturing method can improve energy density because the thickness of the battery is reduced, and the electrode by punching in the process of transferring the base film (polymer film) provided with all of the electrode materials Since a current collector is obtained, the productivity of the electrode current collector can be increased, and the discarded electrode material can be reduced.

1 is a plan view for explaining a process of manufacturing an electrode current collector according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the cutting line “AA” shown in FIG. 1.
3 is a cross-sectional view for explaining a process in which a current collector for an electrode is manufactured according to an embodiment of the present invention.
4 is an exploded perspective view illustrating an electrode assembly formed by stacking an electrode current collector and a separator according to an embodiment of the present invention.
5 is a cross-sectional view of an electrode assembly in which a current collector for an electrode and a separator according to FIG. 4 are stacked.
6 is a plan view illustrating a process in which a modified example of the current collector for an electrode according to an embodiment of the present invention is manufactured.
7 is a plan view for explaining a process of manufacturing a current collector for an electrode according to another embodiment of the present invention.
8 is a cross-sectional view for explaining a process in which the electrode current collector according to FIG. 7 is manufactured.
9 is a cross-sectional view taken along the cutting line “DD” shown in FIG. 8(b).
10 is a plan view illustrating a process in which a modified example of an electrode current collector according to another embodiment of the present invention is manufactured.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited or limited by the embodiments. The same reference numerals in each drawing denote the same members.

1 is a plan view for explaining a process in which a current collector for an electrode is manufactured according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 3 is an embodiment of the present invention Figure 4 is a cross-sectional view for explaining the process of manufacturing a current collector for an electrode according to an example, Figure 4 is an exploded perspective view for explaining an electrode assembly formed by stacking an electrode current collector and a separator according to an embodiment of the present invention, Figure 5 Is a cross-sectional view of the electrode assembly in which the electrode current collector and the separator according to FIG. 4 are stacked.

1 to 3, the current collector for an electrode according to an embodiment of the present invention (CURRENT COLLECTOR FOR ELECTRODES, 100) has a resistance value greater than that of a current collector made of a metal foil, so that the current collector flows through Since the limiting current value of the current can be adjusted and the current blurring can be interrupted by damage to the polymer film, the short circuit current can be lowered when an internal short circuit of the secondary battery occurs.

As described above, the lithium secondary battery provided with the current collector 100 for an electrode according to the present invention may have a characteristic or concept of Max Current Limited Battery (MCLB). Hereinafter, a current collector for an electrode according to the present invention that enables implementation of MCLB will be described.

In addition, the current collector for an electrode according to embodiments of the present invention described below is a concept including both a current collector for a positive electrode and a current collector for a negative electrode, and a current collector for a positive electrode and a current collector for a negative electrode are stacked. The structure of the electrode current collector in the structure of stacking to form the electrode assembly will be described. That is, the current collector for a stack type electrode will be described below.

The current collector 100 for electrodes described with reference to FIGS. 1 to 3 is a current collector for an anode electrode, and reference numeral "300" in FIGS. 4 and 5 is a current collector for a negative electrode. Hereinafter, for convenience of description, the current collector for the positive electrode will be referred to as the current collector 100 for the electrode.

The current collector 100 for an electrode according to the present invention uses a polymer film 101 as a base material (base film) without using a metal foil, and a thin film of metal is coated or coated on the polymer film 101 It is characterized by one thing.

1 to 3, the current collector 100 for an electrode according to an embodiment of the present invention, in order to distinguish the polymer film (polymer film 101 prior to coalescence) is formed of an electrode material integrally formed with the polymer material The film 200 may be formed by punching or cutting along the shape of the current collector 100 for an electrode while one direction of the lengthwise direction of the polymer film 200 is transferred in the same loading direction (L).

Referring to Figure 1, the long strip-shaped polymer polymer film 200 is continuously transferred in the loading direction (L) on the right, while being transported, punched or cut into the shape of the current collector 100 for electrodes (see dotted line) An electrode current collector 100 is obtained. Punching holes P remain in the polymer polymer film 200 in which the electrode current collector 100 is punched or cut.

The current collector 100 for electrodes is punched or cut at both sides of the reference line C so as to be symmetric with respect to the reference line C passing through the center of both ends of the polymer film 200 or the polymer film 101 to be described later. Can lose. At this time, the punching hole (P) formed along the loading direction (L) minimizes the gap between the adjacent punching hole (P) polymer film 200 to be discarded and the electrode current collector (100) Productivity can be increased.

FIG. 2 is a cross-sectional view of the polymer composite film 200 along the cutting line “AA” in FIG. 1, and a cross-sectional view of the current collector 100 for an electrode according to the cutting line “BB” in FIG. 1 is the same as FIG. 3( c ). .

1 to 3, the current collector for electrodes 100 according to an embodiment of the present invention (100, current collector), a polymer film (101, polymer film); A metal piece (120, metal element) provided on at least one surface of the upper and lower surfaces of the polymer film 101; An adhesive layer 130 provided between the polymer film 101 and the metal piece 120; A conductive material 102 formed on surfaces of the polymer film 101 and the metal piece 120; And an electrode active material layer 170 formed on the surface of the conductive material 102.

The polymer film 101 is a base film that is the base of the polymer film 200, and may be provided in a relatively small and long strip shape to have a constant length. Here, the polymer film 101 can continuously form the current collector 100 for an electrode, which will be described later, by winding or unwrapping it along its longitudinal direction, that is, the loading direction L.

The polymer film 101 is preferably made of a non-conductive material such as polyethylene (PE), polypropylene (PP), or polyethylene terephthalate (PET).

The polymer film 101 has a thickness of 50 μm or less, but preferably has a thickness of 1.4 μm or more and 50 μm or less. Electrode current collector 100 according to an embodiment of the present invention can reduce the thickness or weight of the battery than when using a conventional metal foil current collector, a polymer film of a nonconductor having a thickness of 1.4 μm or more and 50 μm or less By using (101) as the basic configuration of the current collector 100, the overall thickness or weight of the lithium secondary battery having the current collector 100 for an electrode according to an embodiment of the present invention can be reduced.

Meanwhile, the polymer film 101 is preferably formed of a material that melts at a temperature lower than 300°C. The lead tab 190, which will be described later, is fixed by welding. If the polymer film 101 does not melt at a temperature lower than the welding temperature of the lead tab 190, the lead tab 190 cannot be combined. Therefore, the polymer film 101 should have a melting point that can be melted in the process of welding the lead tab 190 and preferably has a melting point lower than 300°C.

2 and 3, a conductive material 102, an electrode active material layer 170, and the like are formed on both the upper and lower surfaces of the polymer film 101. In some cases, the upper surface of the polymer film 101 or It may be formed on only one of the lower surfaces. Hereinafter, the current collector 100 for an electrode in which the conductive material 102, the electrode active material layer 170, and the like are formed on the upper and lower surfaces of the polymer film 101 will be described.

2 and 3, the metal piece 120 may be provided on the edge of the polymer film 101 but protruded from the edge of the polymer film 101. The metal piece 120 may be provided to be positioned at both ends of the polymer film 101 in the width direction along the longitudinal direction of the polymer film 101. At this time, the edge of the metal piece 120 and the edge of the polymer film 101 are not matched, but the edge of the metal piece 120 is provided to protrude in the width direction of the polymer film 101 rather than the edge of the polymer film 101 It is preferred.

In other words, it is preferable that the metal piece 120 is provided to be in contact with the surface of the polymer film 101 only partially in its width direction. In this case, the remaining portion of the metal piece 120 is provided in a state that does not contact the polymer film 101, a portion of the metal piece 120 that does not contact the polymer film 101 may form a tab 150 .

The metal piece 120 may serve to secure a position for welding the lead tab 190 described later on the polymer film 101. That is, the metal piece 120 may function as a connecting portion of the lead tab 190.

The metal piece 120 is preferably formed to have a thickness of 5 μm or more. Here, it is sufficient that the metal piece 120 is provided only on a part of the polymer film 101. As described above, it is preferable that the long strip-shaped metal piece 120 is provided so as to protrude outward from the edge of the polymer film 101.

As described above, the metal piece 120 is preferably in the form of a metal thin film or metal foil having a thickness of 5 μm or more, but is not necessarily limited to this form. The metal piece 120 may be provided in the form of a thin film, foil, or mesh to be electrically connected to the lead tab 190 described later.

The metal piece 120 of the current collector 100 for an electrode according to an embodiment of the present invention serves as an electric path to secure a welding position of the lead tab 190 or to secure conductivity when the length of the polymer film 101 is long can do.

Meanwhile, in order to attach the metal piece 120 to the surface of the polymer film 101, an adhesive layer 130 may be formed on one surface of the metal piece 120 facing or facing the polymer film 101.

The adhesive layer 130 adheres to polyvinyl acetate (PVA: Poly Vinyl Alcohol), polyvinyl alcohol (PVA), ethylene vinyl acetate (EVA), acrylate, acid modified PP, etc. It is formed of a material having a component, and preferably has a thickness smaller than 50 μm. Here, the adhesive layer 130 may be formed of a polymer combination of two or more layers in addition to the polymer described above.

In addition, the adhesive layer 130 may be a polymer layer formed of a polymer material. Here, the adhesive layer 130 or the polymer layer may be provided over the entire surface of the metal piece 120 or may be provided on only a portion of the surface of the metal piece 120 to be bonded to the polymer film 101.

On the other hand, a surface treatment including a chromate treatment may be formed on one surface of the metal piece 120 facing or facing the polymer film 101. Surface treatment on the surface of the metal piece 120 is essential, but before attaching the metal piece 120 to the polymer film 101, the surface of the metal piece 120 is subjected to chrome coating (chromate treatment) or Non-Cr treatment (Non Chromate treatment or binder treatment) or simultaneous treatment.

The thickness of the portion where the metal piece 120 is provided on the polymer film 101 is 120 μm or less, including the metal piece 120, and the thickness of the part excluding the metal piece 120 or the part without the metal piece 120 is 100 μm or less. It is preferred.

Meanwhile, the current collector 100 for an electrode according to an embodiment of the present invention may include a conductive material 102 provided on the surface of the polymer film 101 and/or the metal piece 120.

The conductive material 102 may be made of a metal such as copper (Cu), nickel (Ni), aluminum (Al), or a conductive material such as carbon nano tube (CNT) or graphene. It may be, may be formed in a plated or coated state on the surface of the polymer film 101. Therefore, the conductive material 102 may also be referred to as a conductive layer forming a part of the outer surface of the current collector 100.

The conductive material 102 may be formed to adjust or lower the limit current or the maximum current of the electrode current collector 100. In other words, the conductive material 102 refers to a metal or conductive material that is plated or coated on the surfaces of the polymer film 101 and the metal piece 120 to control the conductivity of the current collector 100, and the polymer film When the surface of the 101 and/or metal piece 120 is plated or coated, the conductive material 102 may be referred to as a conductive layer. Hereinafter, it is revealed that the conductive material 102 is a concept including a conductive layer.

By controlling the coating amount or coating thickness of the conductive material 102 that is plated or coated on the surface of the polymer film 101 and/or the metal piece 120, the maximum amount of current flowing through the current collector 100 can be controlled or lowered, This can increase the safety of the lithium secondary battery and ensure the safety of the battery in the event of a short circuit.

In other words, the limiting current or the maximum current flowing through the current collector 100 may be controlled by the thickness or amount of the conductive material 102 formed on the surface of the polymer film 101 and/or the metal piece 120. As such, the concept of a maximum current limited battery (MCLB) of a lithium secondary battery by the conductive material 102 of the current collector 100 for an electrode according to an embodiment of the present invention Can be implemented. In addition, the safety of the battery can be improved because the polymer film 101 may melt when a physical internal short circuit occurs, thereby preventing a rapid current from being generated.

The conductive material 102 may be formed on the surface of the polymer film 101 and/or the metal piece 120 by various methods. For example, when the conductive material 102 is a metal, it may be formed on the surface of the polymer film 101 and/or the metal piece 120 by sputtering, evaporation coating, or electroless plating. have. In addition, the conductive material 102 may be plated or coated by two or more of sputtering, evaporation coating, electroless plating, or electroplating.

Since the thickness of the conductive material 102 can be controlled by controlling the conductivity of the current collector 100 or securing the safety of the battery by the amount (weight) or thickness of the coating or coating, the thickness of the conductive material 102 when plating or coating Or it is necessary to use a method that can control or adjust the weight.

When the conductive material 102 is a metal, it is preferable to use both sputtering and electroplating to control the plating or coating thickness or weight of the conductive material 102. That is, after the conductive material 102 is thinly plated or coated on the surface of the polymer film 101 and/or the metal piece 120 using sputtering, the conductive material 102 is formed thereon again using electroplating. The plating thickness or weight of the conductive material 102 can be easily controlled or adjusted.

Since the sputtering method is more expensive than the electroplating method, the conductive material 102 is plated thinly using sputtering, and then the conductive material 102 is plated using electrolytic plating. In this way, it is advantageous to use sputtering and electrolytic plating together in terms of economical efficiency, and the thickness or weight of the conductive material 102 can be easily adjusted.

The conductive material 102 may be formed on only one surface of the polymer film 101 or may be formed on both surfaces. At this time, the conductive material 102 is preferably formed with a thickness of 0.5 μm based on the minimum cross section and 4 μm based on the maximum cross section.

Meanwhile, the conductive material 102 formed on the surface of the polymer film 101 is plated or coated on the surface of the polymer film 101, or the conductive material 102 formed on the surface of the polymer film 101 is a polymer film 101 ) May also penetrate or pass through the interior. For example, when the polymer film 101 is formed of a porous material, the conductive material 102 plated or coated on one surface of the polymer film 101 reaches the other surface through the pores of the polymer film 101 can do.

When plating or coating the conductive material 102 using the electroless plating method, even if the conductive material 102 is plated or coated on only one side of the porous polymer film 101, the conductive material is introduced into the polymer film 101. Even if the conductive material 102 is plated or coated on only one side of the polymer film 101 because the conductive material 102 reaches to the other side by infiltrating the 102, conductivity can be secured on both sides of the polymer film 101. have.

In addition, since the conductive material 102 is plated or coated after the metal piece 120 is attached to the polymer film 101, the conductive material 102 is plated not only on the surface of the polymer film 101 but also on the surface of the metal piece 120. Or it can be coated. At this time, when the metal piece 120 is a thin film metal foil or a metal mesh type and the polymer film 101 is a porous material, the conductive material 102 formed on the surface of the metal piece 120 passes through the inside of the metal piece 120 It may reach the other surface of the polymer film 101.

However, in some cases, the pores of the polymer film 101, which is a porous material, may need to be removed. In this case, the polymer film 101 is subjected to electroless plating when electroless plating is performed to plate or coat the conductive material 102. The pores are removed by pressing or applying heat.

As described above, the conductive material 102 is made of a metal or a conductive material, is formed in a plated or coated state on the surface of the polymer film 101, and controls the limiting current or the maximum current of the electrode current collector 100. Or lowered.

Since the current collector 100 for an electrode according to an embodiment of the present invention allows current to flow through the conductive material 102, the conductive material 102 is plated or coated on the surface of the polymer film 101. Should be maintained. To this end, it is preferable to increase the binding force between the conductive material 102 and the polymer film 101 by surface treatment of the polymer film 101.

If the binding force between the conductive material 102 and the polymer film 101 is poor, the conductive material 102 and the conductive material 102 may be separated or detached from the surface of the polymer film 101 in the state in which the electrolyte is injected. It is important to increase the binding force between the polymer films 101.

A surface treatment may be formed on the surface of the polymer film 101 to increase adhesion or binding strength with the conductive material 102.

Corona treatment or Ni/Cr treatment may be performed on the surface of the polymer film 101 to increase the binding force between the conductive material 102 and the polymer film 101. Here, in the case of Ni/Cr treatment, it is preferable that the Ni or Cr or Ni/Cr alloy is coated on the polymer film 101 to 10 nm or less.

For example, when the conductive material 102 plated on the surface of the polymer film 101 is copper (Cu), Ni or Cr or Ni/Cr alloy is used to improve the binding force between the copper and the polymer film 101. By coating the surface of the polymer film 101 with a thickness of 10 nm or less, and plating the copper on the Ni/Cr-treated surface, the binding force between the conductive material 102, copper, and the polymer film 101 can be increased. That is, by bonding Ni/Cr on the polymer film 101 first and then coating copper thereon, the binding force between the conductive material 102 and the polymer film 101 can be increased.

In addition, by binding chromium (Cr) to a thickness of 10 nm or less on the surface of the copper, which is the conductive material 102 plated on the surface of the polymer film 101, the binding power of the binder can be improved.

In order to enhance the corrosion resistance of aluminum, which is the conductive material 102, a chromate treatment coating chromium (Cr) on aluminum may be performed, and a treatment coating epoxy type Non-Cr to improve adhesion may be performed on the chromate treatment. Here, the Non-Cr treatment is to coat a compound layer containing zirconium (Zr) or a compound layer containing silicon (Si). It is preferable that the thickness of the chromate treatment and the non-Cr treatment is several nm to tens of nm.

In addition, in order to improve the adhesive strength of the conductive material 102, a treatment of coating a polymer type of Non-Cr on the surface of nickel may be performed. Here, the Non-Cr coating layer is a state in which a metal is dispersed in a polymer. The thickness of the non-Cr treatment is preferably several nm.

Meanwhile, referring to FIGS. 1 to 4, the electrode active material layer 170 may be plated or coated on the surface of the conductive material 102 in the current collector 100 for an electrode according to an embodiment of the present invention. The electrode active material layer 170 may be referred to as an electrode layer having electrical characteristics according to the polarity of the current collector 100. When the current collector 100 has the polarity of the positive electrode, the electrode active material layer 170 may be plated or coated with a positive electrode active material, and when the negative electrode has the polarity, the electrode active material layer 170 may be plated or coated with a negative electrode active material. Can be.

Here, unlike the conductive material 102, the electrode active material layer 170 is preferably not formed on the metal piece 120. In other words, it is preferable that the electrode active material layer 170 is not formed on the surface of the conductive material 102 that is plated or coated on the surface of the metal piece 120. 1, it is preferable that the electrode active material layer 170 is formed on the metal piece 120 provided at both ends in the width direction of the polymer film 101.

Meanwhile, the current collector 100 for an electrode according to an embodiment of the present invention includes an electrode part 140 on which the electrode active material layer 170 is formed, and a tab part 150 on which the electrode active material layer 170 is not formed. Can. The electrode portion 140 and the tab portion 150 are integrally formed, but the cross-sectional structure is different. Referring to (c) of FIG. 3, the cross-sectional structure of the electrode portion 140 includes the electrode active material layer 170, the conductive material 102 and the polymer film 101, and the cross-sectional structure of the tab portion 150 is conductive. It may include an ash 102, a metal piece 120, an adhesive layer 130 and a polymer film 101.

As described above, the tab portion 150 is an important component of the metal piece 120, and preferably has a shape protruding from any one edge of the electrode portion 140. Here, the tab unit 150 may be referred to as a “plain projection”. "Rainbow protrusion" means that the electrode active material layer 170 is not formed and is a portion protruding from the electrode portion 140.

4 is an exploded perspective view illustrating a process of forming the electrode assembly 10 of a secondary battery by alternately stacking the current collectors 100 for electrodes. In FIG. 4, the current collector 100 for an electrode is a positive electrode current collector, a reference numeral “300”, and a current collector for a negative electrode, and “500” is a separator. The current collector 300 for the negative electrode has the same structure as the current collector 100 for the electrode (for the positive electrode) described in FIGS. 1 to 3 and may be manufactured by the same process. However, the components of the current collector 100 for the positive electrode, the conductive material 102, and the electrode active material layer 170 are different.

Referring to FIG. 4, the current collector 300 for a negative electrode may also include an electrode part 340 and a tab part 340. The electrode assembly 10 can be obtained by stacking the current collector 100 for the positive electrode and the current collector 300 for the negative electrode so that the separator 500 is positioned between them. At this time, the tab 150 of the current collector 100 for the positive electrode and the tab 350 of the current collector 300 for the negative electrode are preferably formed so as not to overlap each other.

Meanwhile, the current collector 100 for an electrode according to an embodiment of the present invention may include a lead tab 190 for connection with an external device.

The existing metal foil current collector can directly weld a lead tab to the metal foil, but the current collector 100 for an electrode according to an embodiment of the present invention is a polymer film 101 having a configuration corresponding to the existing metal foil. Therefore, it is impossible to directly weld the lead tab to the polymer film 101. The current collector 100 for an electrode according to an embodiment of the present invention can solve this problem by attaching the metal piece 120 to the surface of the polymer film 101 and welding the lead tab 190 to the metal piece 120. have.

In the current collector 100 for an electrode according to an embodiment of the present invention, the lead tab 190 is a metal piece 120 by ultrasonic welding, laser welding, or spot welding. Can be welded to.

When the lead tab 190 is welded to the metal piece 120, the polymer film 101 under the metal piece 120 is melted by welding heat. Since the polymer film 101 is melted, the lead tab 190 may be electrically connected to the conductive material 102. That is, the lead tab 190 may be welded to the metal piece 120, but the polymer film 101 may be melted to be electrically connected to the metal piece 120 and the conductive material 102.

3, the metal piece 120 and the conductive material 102 are provided on both sides of the polymer film 101, and the metal pieces 120 provided on both sides of the polymer film 101 may be formed at the same position. have.

Here, it can be seen that the metal pieces 120 are positioned on both the upper and lower sides of the polymer film 101, and the metal pieces 120 are provided at the same or symmetrical positions. The conductive film 102 may be plated or coated on the surfaces of the polymer film 101 and the metal piece 120 after the metal pieces 120 are attached to the same position on both sides of the polymer film 101 by the adhesive layer 130. . At this time, the conductive material 102 is plated or coated on both the upper and lower sides of the polymer film 101, and the conductive material 102 is also plated or coated on the surface of the metal piece 120 provided on the upper and lower sides of the polymer film 101. Can.

Referring to FIG. 5, a lead tab 190 may be connected to any one of the metal pieces 120 provided on the upper and lower sides of the polymer film 101. The lead tab 190 may be connected to the metal piece 120 in a state where the conductive material 102 is coated or coated on the surface of the metal piece 120.

When the lead tab 190 is welded to any one of the metal pieces 120 provided on both sides of the polymer film 101, the metal film provided on both sides of the polymer film 101 by recording the polymer film 101 120 are connected to each other, and as a result, the lead tab 190 may be electrically connected to the conductive material 102 provided on both sides of the polymer film 101 at the same time.

Ultrasonic welding, laser welding or spot welding the lead tab 190 to the metal piece 120 provided on the upper surface of the polymer film 101 while the metal piece 120 and the conductive material 102 are provided on both sides of the polymer film 101. When welding, a part of the polymer film 101 is melted. The polymer film 101 was previously mentioned as having a melting point at a temperature lower than 300°C. Since the welding heat generated when welding the lead tab 190 is higher than 300°C, the polymer film 101 may melt during the welding process.

Since the polymer film 101 does not exist in the portion where the polymer film 101 is melted as described above, the upper and lower metal pieces 120 may directly contact each other. At this time, since the metal pieces 120 are also melted by welding heat, the upper and lower metal pieces 120 are joined together. Therefore, since the polymer film 101 is melted and directly melt-bonded between the upper and lower metal pieces 120 in the portion where the polymer film 101 is not melted, the lead tab 190 welded to any one metal piece 120 is not only the upper and lower metal pieces 120, but also the polymer film 101 ) May be electrically connected to the conductive material 102 formed on the upper and lower surfaces.

The electrode current collector 100 according to an embodiment of the present invention is a lead tab 190 because the metal piece 120 remains connected to the polymer film 101 even if a portion of the polymer film 101 is melted by welding heat. It is possible to connect ).

However, in some cases, the lead tab 190 may be welded to the metal piece 120 even when the polymer film 101 is not melted. When the polymer film 101 is a porous material, the polymer film 101 is not melted because the conductive material 102 penetrates the polymer film 101 through pores and is electrically connected to both surfaces of the polymer film 101. In the lead tab 190 connected to the metal piece 120 may be electrically connected to the conductive material 102 of the polymer film 101.

On the other hand, the electrical connection between the metal piece 120 and the conductive material 102 may be weakened in a region where the lead tab 190 is welded. For example, when the conductive material 102 formed on the surface of the metal piece 120 is melted by welding heat, the electrical connection between the metal piece 120 and the conductive material 102 may be deteriorated. The present invention is a tab to prevent the electrical connection between the metal piece 120 and the conductive material 102 is weakened at the site where the lead tab 190 is welded or to strengthen the electrical connection between the metal piece 120 and the conductive material 102 The cover member 180 can be used.

Referring to the current collector 100 for an electrode according to an embodiment of the present invention shown in FIG. 5, the tab cover member 180 includes a conductive material 102, a metal piece 120, an electrode active material layer 170, and a lead It may be formed to contact the tab 190.

Here, the tab cover member 180 is preferably in the form of a conductive tape covering a portion where the lead tab 190, the metal piece 120, the electrode active material layer 170, and the conductive material 102 are electrically connected to each other. Do.

Among the inner and outer surfaces of the tab cover member 180, the inner surface contacting the lead tab 190, the metal piece 120, and the conductive material 102 is formed of a conductive material to enhance the conductivity of the lead tab 190. have. That is, since the inner surface of the tab cover member 180 having conductivity is in contact with the lead tab 190, the metal piece 120 and the conductive material 102 at the same time, through the inner surface of the tab cover member 180 and the metal piece 120 The conductive material 102 may maintain or strengthen the electrical connection, and as a result, conductivity between the lead tab 190, the metal piece 120, and the conductive material 120 may be enhanced.

On the other hand, the outer surface of the tab cover member 180 that does not contact the lead tab 190, the metal piece 120, and the conductive material 102 among the inner and outer surfaces is preferably formed of a non-conductive material.

As such, the tab cover member 180 may include a conductive material to electrically connect the metal piece 120 and the conductive material 102 or enhance conductivity between the metal piece 120 and the conductive material 102.

Since the connecting portion of the lead tab 190 is covered with the tab cover member 180 having conductivity, not only the conductivity between the lead tab 190, the metal piece 120, and the conductive material 120 is enhanced, but also of the lead tab 190, You can also protect the connection site.

As described above, the lead tab 190 is welded to the metal piece 120 and electrically connected to the metal piece 120 and the conductive material 102, and the polymer film 101 has a conductive material 102, a metal piece 120, A tab cover member 180 electrically connected to the electrode active material layer 170 and the lead tab 190 and covering the lead tab 190 may be provided.

The tab cover member 180 may be formed to electrically connect the metal piece 120 and the conductive material 102 by including a conductive material, or to enhance the conductivity between the metal piece 120 and the conductive material 102.

5 illustrates a stacked cross-sectional structure of a current collector 100 for an anode electrode, a separator 500, and a current collector 300 for a negative electrode. In FIG. 5, reference numeral "370" denotes an electrode active material layer for a negative electrode, "301" a polymer film for a negative electrode, "302" a conductive material for a negative electrode, "330" an adhesive layer, "320" a metal piece for a negative electrode, "390 "Silver" is a negative lead tab, and "380" is a negative tab cover member.

Hereinafter, a method of manufacturing a current collector for an electrode according to an embodiment of the present invention will be described.

The present invention, preparing a polymer film 101 in the form of a strip; Bonding the metal piece 120 to at least one of both ends in the width direction of the polymer film 101; Coating the conductive material 102 to cover the surfaces of the polymer film 101 and the metal piece 120; Coating the electrode active material layer 170 on the surface of the conductive material 102 except for the portion where the metal piece 120 is located; And obtaining a current collector 100 for the electrode by punching or cutting along the shape of the current collector 100 for the electrode while transferring the polymer film 101 in the loading direction (L). ) Can be provided.

1 to 3, after placing the long strip-shaped metal piece 120 on both ends in the width direction of the long strip-shaped polymer film 101, it is adhered.

In the step of adhering the metal piece 120 to the polymer film 101, as shown in FIG. 3(a), the metal piece 120 protrudes from both ends in the width direction of the polymer film 101. The metal piece 120 may be positioned on at least one of the upper and lower surfaces of the.

In addition, in the step of adhering the metal piece 120 to the polymer film 101, the adhesive layer 130 may be provided between the metal piece 120 and the polymer film 101 facing each other. That is, the metal piece 120 and the polymer film 101 may be bonded using the adhesive layer 130.

Next, as shown in (b) of FIG. 3, a step of coating the conductive material 102 to cover the surfaces of the polymer film 101 and the metal piece 120 may be performed. The conductive material 102 may be plated or coated on both sides of the polymer film 101 and may also be plated or coated on the surface of the metal piece 120 provided at both ends in the width direction of the polymer film 101.

Next, as shown in (c) of FIG. 3, a step of coating the electrode active material layer 170 on the surface of the conductive material 102 may be performed, except for the portion where the metal piece 120 is located. . After the process of (a) to (c) of FIG. 3, a polymer polymer film 200 is obtained.

Then, the step of obtaining the current collector 100 for an electrode may be performed by punching or cutting along the shape of the current collector 100 for the electrode while transferring the coalescence polymer film 200 in the loading direction L. The step of obtaining the current collector 100 for an electrode while transferring in the loading direction L is performed while transferring the coalescence polymer film 200 having a cross-sectional structure shown in FIG. 3(c) along the loading direction L Can be performed.

In the step of obtaining the current collector for the electrode, as shown in FIG. 1, the electrode portion 140 of the current collector for electrode 100 is a portion of the polymer composite film 200 coated with the electrode active material layer 170. It is formed by being punched or cut, and the tab portion 150 of the current collector 100 for electrodes may be formed by being punched or cut at a portion where the metal piece 120 is located.

Referring to Figure 1, in the step of obtaining the current collector 100 for the electrode, the electrode current collector 100 is symmetrical with respect to the reference line (C) passing through the center of both ends in the longitudinal direction of the polymer film 200 To this end, it can be punched or cut from both sides of the baseline (C). In FIG. 1, the punching hole P means a portion in which the current collector 100 for an electrode is punched or cut in the coalescence polymer film 200, that is, a portion in which the current collector 100 for an electrode is cut off.

According to the above-described manufacturing method, the current collector 100 for electrodes is punched or cut at both sides of the reference line (C) while the polymer polymer film 200 is transported along the loading direction (L) along the loading direction (L). Since it is manufactured, productivity of the electrode current collector 100 can be increased, and material can be prevented from being wasted.

On the other hand, Figure 6 is a plan view for explaining the process of manufacturing a modified example of the current collector for an electrode according to an embodiment of the present invention. When comparing FIGS. 1 and 6, the metal piece 120 is not a single metal piece having a band shape, but has a difference in that it is provided in a plurality of discrete shapes. That is, in the case of Figure 1, the metal piece 120 is provided on each of the width direction of the polymer film 200, one each, but is provided as a single metal piece having a long strip shape, such as the polymer film 200, In the case of FIG. 6, the metal piece 120 has a shortly divided shape, and is different in that a plurality of pieces are discontinuously disposed along the longitudinal direction at the edge of the polymer film 200.

Referring to FIG. 6, it is preferable that the metal pieces 120 in which a plurality are discontinuously provided have the same shape and are positioned along both ends of the polymer polymer film 200 in the width direction, but are spaced apart at the same distance. Here, the metal piece 120 is preferably provided at a position where the tab 150 is formed when the electrode current collector 100 is punched. Because, since the metal piece 120 is included in the tab portion 150, it is sufficient to place the metal piece 120 only in the portion where the tab portion 150 is formed.

The polymer film 101 may be exposed between the metal pieces 120. The conductive film 102 may or may not be coated on the polymer film 101 exposed on the metal piece 120.

By doing this, it is possible to reduce the metal pieces 120 that are not used for the formation of the tab portion 150 because they are between the tab portions 150.

Hereinafter, a current collector 200 for an electrode according to another embodiment of the present invention will be described with reference to FIGS. 7 to 10. For convenience, repeated descriptions of the same contents as the current collector 100 for an electrode according to an embodiment of the present invention described above are omitted, and different from the current collector for an electrode according to an embodiment of the present invention described above The current collector for an electrode according to another embodiment of the present invention will be described with focus on the contents.

7 is a plan view for explaining a process of manufacturing an electrode current collector according to another embodiment of the present invention, FIG. 8 is a cross-sectional view for explaining a process of manufacturing an electrode current collector according to FIG. 7, FIG. 9 is It is sectional drawing along the cutting line "DD" shown in FIG. 8(b).

The electrode current collector 1000 described in FIGS. 7 to 9 is a current collector for an anode electrode. Hereinafter, for convenience of description, the current collector for the positive electrode will be referred to as a current collector 1000 for the electrode.

7 to 9, the current collector 1000 for an electrode according to another embodiment of the present invention, in order to distinguish from the polymer film (polymer film 1010 before coalescing), the electrode material is integrally formed with an electrode material The polymer film (2000)' may be formed by punching or cutting along the shape of the current collector 1000 for electrodes while transferring one direction of the lengthwise direction of the polymer film 2000 in the same loading direction (L). .

Referring to FIG. 7, the long strip-shaped polymer polymer film 2000 is continuously transferred in the loading direction (L) on the right side, and is punched or cut into the shape of the current collector 1000 for electrodes (see dotted line) during transport. An electrode current collector 1000 is obtained. Punching holes P remain in the polymer polymer film 2000 in which the electrode current collector 1000 is punched or cut.

The current collector 1000 for electrodes may be punched or cut at both sides of the reference line C so as to be symmetric with respect to the reference line C orthogonal to the longitudinal direction of the coalescence polymer film 2000 or the polymer film 1010 to be described later. . At this time, the punching hole (P) formed along the loading direction (L) minimizes the gap between the adjacent punching hole (P) polymer film 2000 is discarded and the electrode current collector (1000) of the Productivity can be increased.

7 to 9, the current collector for electrodes (1000, current collector) according to another embodiment of the present invention, a polymer film (1010, polymer film); A metal piece (1200, metal element) provided on at least one surface of the upper and lower surfaces of the polymer film 1010; An adhesive layer 1300 provided between the polymer film 1010 and the metal piece 1200; A conductive material 1020 formed on surfaces of the polymer film 1010 and the metal piece 1200; And an electrode active material layer 1700 formed on the surface of the conductive material 1020.

The metal piece 1200 may be provided to protrude from the edge of the hole 101a formed in the polymer film 1200. That is, referring to FIG. 7, since the end of the tab portion 1500 is located in the hole 101a formed in the polymer film 1010, when the current collector 1000 for an electrode is punched or cut in this state, the tab portion 1500 In the cross-sectional structure of the metal piece 1200 has a shape protruding from the edge of the hole (101a).

Since the metal piece 1200 is placed above the hole 101a formed by cutting the polymer film 1010, the hole 101a in FIG. 7 is indicated by a dotted line (hidden line).

Referring to FIGS. 7 and 8, a plurality of holes 101a formed in the polymer film 1010 have the same shape along a direction orthogonal to the longitudinal direction of the polymer film 1010 or a width direction of the polymer film 1010. And spaced apart at the same interval. Here, it can be said that the plurality of holes 101a located on the same line in the direction perpendicular to the longitudinal direction of the polymer film 1010 constitutes one hole set.

A plurality of such hole sets may be formed along the longitudinal direction of the polymer film. Referring to FIG. 7, four holes 101a are formed on one line in a direction orthogonal to the longitudinal direction of the polymer film 1010, and these four holes 101a form one hole set. do. Then, it can be seen that four hole sets (including the electrode current collector already punched part) are formed along the length direction of the polymer film 1010.

Although one hole set is shown in FIG. 7 as including four holes, the number of holes included in the hole set may vary depending on the size of the electrode current collector 1000 or the polymer film 1010. In addition, the number of hole sets may vary depending on the length of the polymer film 1010.

Referring to FIG. 8(a), a plurality of holes 101a are formed in the polymer film 1010 where the conductive material 1020 and the electrode active material layer 1700 are not coated. Here, the hole 101a is a portion in which the polymer film 1010 is cut out, and is a portion without the polymer film 1010. There are no restrictions on the shape or size of the hole 101a. The size or shape of the hole 101a is sufficient as long as the end of the tab portion 1500 of the current collector 1000 for electrodes to be manufactured is inside the hole.

Referring to FIG. 8(b), the metal piece 1200 is positioned on one hole set to cover all the holes 101a included in one hole set. Here, the number of metal pieces 1200 is preferably the same as the number of hole sets. In other words, a plurality of metal pieces 1200 are placed on the polymer film 1010 along the longitudinal direction of the polymer film 1010 so as to cover the hole 101a.

Here, the metal piece 1200 is not simply placed on the polymer film 1010, but must be adhered to the surface of the polymer film 1010 so that the position does not change. To this end, as illustrated in FIG. 9, an adhesive layer 1300 may be provided between the metal piece 1200 and the polymer film 1010.

In other words, the metal piece 1200 has a size sufficient to completely cover or partially cover the hole 101a and is provided in plural to correspond to the hole set, and between the metal piece 1200 and the polymer film 1010 facing each other. An adhesive layer 1300 may be provided.

After the metal piece 1200 is adhered to the polymer film 1010 to cover the hole 101a, as shown in FIG. 8(c), a conductive material is applied to the surfaces of the polymer film 1010 and the metal piece 1200. Plating or coating (1020).

Next, as shown in (d) of FIG. 8, the electrode active material layer 1700 is plated or coated on a portion between the metal pieces 1200 to obtain a coalescence polymer film 2000. After the process of (a) to (d) of FIG. 8, the polymer polymer film 2000 shown in FIG. 7(1) can be obtained.

Here, the adhesive layer 1300, the conductive material 1020, the metal piece 1200, and the electrode active material layer 1700 may be formed on both sides of the polymer film 1010, or may be formed only on one side of the polymer film 1010 It might be. Hereinafter, a case formed on both surfaces of the polymer film 1010 will be described as an example.

As described above, when the metal piece 1200 is provided to protrude from the edge of the hole 101a formed in the polymer film 1010, the remaining part (ie, the protruding end) of the metal piece 1200 is provided with the polymer film 1010. It is provided in a non-contact state, a portion of the metal piece 1200 that does not contact the polymer film 1010 may form a tab 1500.

Here, it is sufficient that the metal piece 1200 is provided only on a part of the polymer film 1010. As described above, it is preferable that a plurality of metal pieces 1200 are discontinuously provided along the longitudinal direction of the polymer film 1010.

On the other hand, unlike the conductive material 1020, the electrode active material layer 1700 is preferably not formed on the metal piece 1200. In other words, it is preferable that the electrode active material layer 1700 is not formed on the surface of the conductive material 1020 coated or coated on the surface of the metal piece 1200. Referring to (d) of FIG. 8, it is preferable that the electrode active material layer 1700 is not formed between the metal pieces 1200 spaced apart along the longitudinal direction of the polymer film 1010.

The current collector 1000 for an electrode according to another embodiment of the present invention may include an electrode portion 1400 on which the electrode active material layer 1700 is formed and a tab portion 1500 on which the electrode active material layer 1700 is not formed. have. The electrode portion 1400 and the tab portion 1500 are integrally formed, but the cross-sectional structure is different. The cross-sectional structure of the electrode portion 1400 includes the electrode active material layer 1700, the conductive material 1020 and the polymer film 1010, and the cross-sectional structure of the tab portion 1500 includes the conductive material 1020, the metal piece 1200, An adhesive layer 1300 and a polymer film 1010 may be included.

Hereinafter, a method of manufacturing a current collector for an electrode according to another embodiment of the present invention will be described.

Another embodiment of the present invention, the step of providing the polymer film 1010 in the form of a strip; Forming a plurality of holes 101a in the polymer film 1010 in a direction orthogonal to the length direction of the polymer film 1010 or in a width direction of the polymer film 1010; Bonding the metal piece 1200 to the polymer film 1010 in a direction orthogonal to the longitudinal direction of the polymer film 1010 or a width direction of the polymer film 1010 to cover the hole 101a; Coating the conductive material 1020 to cover the surfaces of the polymer film 1010 and the metal piece 1200; Coating the electrode active material layer 1700 on the surface of the conductive material 1020 except for the portion where the metal piece 1200 is located; And obtaining a current collector 1000 for electrodes by punching or cutting along the shape of the current collector 1000 for electrodes while transferring the polymer film 1010 in the loading direction (L). You can provide a method.

Referring to (a) of FIG. 8, in the step of forming a plurality of holes in the polymer film, holes 101a having the same shape are formed at the same distance along the width direction of the long-stranded polymer film 1010. . A plurality of holes 101a are formed in the same shape and the same interval in the direction perpendicular to the longitudinal direction of the polymer film 1010 or in the width direction of the polymer film 1010 to form a single hole set, and the hole set is a polymer film A plurality may be formed along the longitudinal direction of (1010). Here, since the hole set has been described above, repeated description will be omitted.

Next, as shown in (b) of FIG. 8, in the step of adhering the metal piece, the metal piece 1200 completely covers the plurality of holes 101a included in one hole set or the hole 101a It has a size sufficient to cover only a portion of and may be provided in plural along the longitudinal direction of the polymer film 1010 to correspond to the hole set. When the position of the metal piece 1200 is changed while the metal piece 1200 is placed on the surface of the polymer film 1010, the relative position of the metal piece 1200 and the hole 101a also changes, so the metal piece on the surface of the polymer film 1010 ( 1200). To this end, an adhesive layer 1300 may be provided between the metal pieces 1200 and the polymer film 1010 facing each other. That is, the metal piece 1200 and the polymer film 1010 may be bonded using the adhesive layer 1300.

Next, as shown in (c) of FIG. 8, the conductive material 1020 is plated or coated on the surfaces of the polymer film 1010 and the metal piece 1200. The conductive material 1020 is preferably plated or coated on the surface of the metal piece 1200 adhered to the polymer film 1010 as well as the surface of the polymer film 1010.

Next, as shown in FIG. 8(d), the electrode active material layer 1700 is plated or coated on a portion between the metal pieces 1200. That is, the electrode active material layer 1700 is plated or coated to cover the conductive material 1020 plated on the polymer film 1010 along the longitudinal direction of the polymer film 1010. At this time, it is preferable to plate or coat the electrode active material layer 1700 so as not to cover the plated conductive material 1020 on the surface of the metal piece 1200.

8 (a) to (d), while transferring the polymer polymer film 2000 obtained through the process in the loading direction (L) while punching or cutting along the shape of the current collector 1000 for electrodes, the current collector 1000 for electrodes ).

In the step of obtaining the current collector 1000 for an electrode, as illustrated in FIG. 7, the electrode active material layer 1700 is coated in the electrode polymer 12000 of the polymer polymer film 2000 as illustrated in FIG. 7. It is formed by being punched or cut at the part, and the tab part 1500 of the current collector 1000 for electrodes can be formed by being punched or cut at the part where the metal piece 1200 and the hole 101a are simultaneously located.

Referring to FIG. 7, in the step of obtaining the current collector 1000 for an electrode, the electrode current collector 1000 has a metal piece 1200 in the middle between two metal pieces 1200 that face each other at a relatively long distance. ) May be formed by being punched or cut at both sides of the reference line C so as to be symmetric with respect to the reference line C passing in a direction parallel to the longitudinal direction. In FIG. 7(1), the punching hole P means a portion in which the electrode current collector 1000 is punched or cut in the coalescence polymer film 2000, that is, a portion in which the electrode current collector 1000 is cut off.

According to the above-described manufacturing method, the current collector 1000 for electrodes is punched or cut at both sides of the reference line (C) while the polymer polymer film 2000 is transported along the loading direction (L) along the loading direction (L). Since it is manufactured, productivity of the electrode current collector 1000 can be increased, and material can be prevented from being wasted.

On the other hand, Figure 10 is a plan view for explaining the process of manufacturing a modified example of the current collector for an electrode according to another embodiment of the present invention. 7 and 10, there is a difference in that the metal piece 1200 is not a strip shape formed continuously in the width direction of the polymer film 1010 but is provided in a plurality of divided shapes. In addition, there is a difference in that the divided metal piece 1200 does not completely cover the hole 101a, but only a part of the hole 101a. That is, in FIG. 7, the metal piece 1200 is provided in the form of a long strip along the width direction of the polymer composite film 200 to completely cover all holes in the hole set, whereas in FIG. 10, the metal piece 1200 is It is different in that it has a shortly divided shape and a plurality of holes are arranged to cover only a part of each hole in the hole set. Here, the plurality of metal pieces 1200 divided and discontinuously disposed are provided in the same number as the holes 101a.

Referring to FIG. 10, it is preferable that the metal pieces 1200 provided in plural have the same shape and are located on the same line along the width direction of the polymer film 2000, but are spaced apart at the same distance. Here, the metal piece 1200 is preferably provided at a position where the tab portion 1500 is formed when the electrode current collector 1000 is punched. Because, the metal piece 1200 is included in the tab portion 1500, it is sufficient to place the metal piece 1200 only in the portion where the tab portion 1500 is formed.

The tab portion 1500 should be formed at a portion where the metal piece 1200 and the hole 101a overlap. In other words, as long as the tab portion 1500 can be formed (punched) in the hole 101a, the metal piece 1200 may cover the hole 101a completely but partially.

By doing so, it is possible to reduce the metal piece 1200 that is not used for the formation of the tab portion 1500 because it is between the tab portions 1500.

As described above, in the embodiments of the present invention, it has been described by specific matters such as specific components, etc., and limited embodiments and drawings, which are provided to help a more comprehensive understanding of the present invention. It is not limited, and those skilled in the art to which the present invention pertains can make various modifications and variations from these descriptions. Therefore, the spirit of the present invention is not limited to the described embodiments, and should not be determined. It will be said that not only the claims described below, but also all equivalent or equivalent modifications to the claims fall within the scope of the spirit of the present invention.

10: electrode assembly 100,1000: electrode current collector
101,1010: polymer film 102,1020: conductive material
120,1200: Metal piece 130,1300: Adhesive layer
140,1400: electrode part 150,1500: tab part
170,1700: electrode active material layer 180: tab cover member
190: lead tab 200,2000: polymer composite film
300: current collector for negative electrode 500: separator

Claims (12)

delete Polymer film;
A metal piece provided on at least one surface of the upper and lower surfaces of the polymer film;
An adhesive layer provided between the polymer film and the metal piece;
A conductive material formed on surfaces of the polymer film and the metal piece; And
Includes; electrode active material layer formed on the surface of the conductive material,
The metal piece is a current collector for an electrode, characterized in that provided to protrude from the edge of the hole formed in the polymer film.
A polymer film, a metal piece provided on at least one of the upper and lower surfaces of the polymer film, an adhesive layer provided between the polymer film and the metal piece, a conductive material formed on the surface of the polymer film and the metal piece, and formed on the surface of the conductive material In the manufacturing method of the current collector for an electrode comprising a layer of electrode active material, the metal piece is located on the edge of the polymer film, but is provided to protrude from the edge of the polymer film,
Preparing the polymer film in a strip form;
Bonding the metal piece to at least one of both ends in the width direction of the polymer film;
Coating the conductive material to cover the surface of the polymer film and the metal piece;
Coating the electrode active material layer on the surface of the conductive material except for the portion where the metal piece is located; And
Obtaining the current collector for the electrode by punching or cutting along the shape of the current collector for the electrode while transferring the polymer film in the loading direction;
Including,
In the step of adhering the metal piece, the metal piece is positioned on at least one of the upper and lower surfaces of the polymer film so that it protrudes from both ends in the width direction of the polymer film, and the adhesive layer is between the metal piece and the polymer film facing each other. Is prepared,
In the step of obtaining the current collector for the electrode, the electrode portion of the current collector for electrodes is formed by punching or being cut at a portion coated with the electrode active material layer, and the tab portion of the current collector for electrodes is punched at a portion where the metal piece is located or Method of manufacturing a current collector for an electrode characterized in that it is cut and formed.
delete delete delete According to claim 3,
In the step of obtaining the current collector for the electrode,
The electrode current collector is a method for manufacturing an electrode current collector, characterized in that it is punched or cut at both sides of the reference line so as to be symmetric with respect to a reference line passing through the center of both ends in the longitudinal direction of the polymer film.
In the method of manufacturing a current collector for an electrode according to claim 2,
Preparing the polymer film in a strip form;
Forming a plurality of holes in the polymer film in a direction orthogonal to the length direction of the polymer film or a width direction of the polymer film;
Bonding the metal piece to the polymer film in a direction orthogonal to the longitudinal direction of the polymer film or a width direction of the polymer film to cover the hole;
Coating the conductive material to cover the surface of the polymer film and the metal piece;
Coating the electrode active material layer on the surface of the conductive material except for the portion where the metal piece is located; And
Obtaining the current collector for the electrode by punching or cutting along the shape of the current collector for the electrode while transferring the polymer film in the loading direction;
Method for producing a current collector for an electrode comprising a.
The method of claim 8,
In the step of forming a plurality of holes in the polymer film,
The holes are formed in a single hole set by forming a plurality of the same shape and the same spacing in the direction orthogonal to the longitudinal direction of the polymer film or the width direction of the polymer film,
The hole set is a method of manufacturing a current collector for an electrode, characterized in that formed in plural along the longitudinal direction of the polymer film.
The method of claim 9,
In the step of bonding the metal piece,
The metal piece has a size sufficient to completely or partially cover the hole and is provided in plural to correspond to the hole set,
Method for manufacturing a current collector for an electrode, characterized in that the adhesive layer is provided between the metal piece and the polymer film facing each other.
The method of claim 10,
In the step of obtaining the current collector for the electrode,
The electrode portion of the current collector for electrodes is formed by punching or being cut at a portion coated with the electrode active material layer, and the tab portion of the current collector for electrodes is formed by punching or being cut at a portion where the metal piece and the hole are simultaneously located. Method for manufacturing a current collector for an electrode.
The method of claim 11,
In the step of obtaining the current collector for the electrode,
The current collector for the electrode is to be punched or cut at both sides of the reference line so as to be symmetrical with respect to a reference line passing in the direction parallel to the length direction of the metal piece in the middle between two metal pieces facing each other at a relatively long distance. Method of manufacturing a current collector for an electrode, characterized in that.

Images