KR20200085398A - Copper Current Collector for All-Solid-State Secondary Battery, Method for Manufacturing The Same, and All-Solid-State Secondary Battery Comprising The Same - Google Patents

Abstract

Disclosed are a negative electrode current collector capable of securing a secondary battery with a high capacity retention rate by suppressing the capacity loss of an all-solid secondary battery due to a reaction with gas generated from a solid electrolyte, a manufacturing method thereof, and an all-solid secondary battery including the same. The negative electrode current collector for an all-solid secondary battery of the present invention includes a copper film having a first surface and a second surface opposite to the first surface; and a first corrosion resistant layer on the first surface, wherein the first corrosion resistant layer includes copper oxynitride.

Description

Cathode current collector for all-solid secondary battery, manufacturing method thereof, and all-solid secondary battery including the same {Copper Current Collector for All-Solid-State Secondary Battery, Method for Manufacturing The Same, and All-Solid-State Secondary Battery Comprising The Same }

The present invention relates to an anode current collector for an all-solid-state secondary battery, a method for manufacturing the same, and an all-solid-state secondary battery including the same, more specifically, a capacity loss of the all-solid-state secondary battery due to reaction with gas generated from a solid electrolyte. The present invention relates to a negative electrode current collector capable of securing a secondary battery having a high capacity retention rate by suppressing it, a manufacturing method thereof, and an all-solid secondary battery comprising the same.

A secondary battery is a type of energy conversion device that generates electricity by converting and storing electrical energy in the form of chemical energy and converting the chemical energy into electrical energy when electricity is needed. battery)”.

Secondary batteries that have economic and environmental advantages over disposable primary batteries include lead-acid batteries, nickel-cadmium secondary batteries, nickel-hydrogen secondary batteries, and lithium-ion secondary batteries.

Lithium ion secondary batteries can store a relatively large amount of energy relative to size and weight compared to other types of secondary batteries. Therefore, lithium-ion secondary batteries are preferred in the field of information and communication devices where portability and mobility are important, and their application ranges are also expanding as energy storage devices for hybrid vehicles and electric vehicles.

However, the lithium ion secondary battery has a serious problem of liquid leakage and ignition/explosion because it contains an inflammable organic electrolyte solution between the positive electrode and the negative electrode.

Research into all-solid-state secondary batteries capable of solving the problems of the lithium-ion secondary batteries has been actively conducted.

The all-solid-state secondary battery is a next-generation battery in which an electrolyte serving as a medium for transferring lithium ions between an anode and a cathode is changed from liquid to solid. In the all-solid-state secondary battery, a flame-retardant solid electrolyte replaces the liquid electrolyte and separator of the existing lithium-ion secondary battery. Since the flame retardant solid electrolyte has no flammability of the liquid electrolyte and an exothermic reaction with an active material is fundamentally blocked, stability and reliability of the battery can be significantly improved compared to a conventional lithium ion secondary battery.

Since the all-solid secondary battery has high voltage stability, it is possible to increase the driving voltage compared to the existing lithium ion secondary battery. In addition, a separator for preventing electrical short circuit between the positive electrode and the negative electrode may be omitted, so that a high energy density can be realized compared to a conventional lithium ion secondary battery.

As a solid electrolyte of the all-solid-state secondary battery, a sulfide-based solid electrolyte, an oxide-based solid electrolyte, and an amorphous-based solid electrolyte can be used. Among them, sulfide-based solid electrolytes having a high ionic conductivity comparable to conventional liquid electrolytes are receiving the most attention.

However, the sulfide-based solid electrolyte easily reacts with water or moisture to generate hydrogen sulfide (H ₂ S). Hydrogen sulfide generated during battery manufacturing and charging and discharging reacts with copper foil used as a negative electrode current collector to cause a copper sulfide (Cu ₂ S/CuS) layer on its surface, thereby increasing the initial resistance of the battery and The discharge capacity is drastically reduced.

Accordingly, the present invention relates to a negative electrode current collector for an all-solid-state secondary battery, a method of manufacturing the same, and an all-solid-state secondary battery including the same, which can prevent problems caused by limitations and disadvantages of the related art.

One aspect of the present invention, by suppressing the capacity loss of the all-solid secondary battery due to the reaction with the gas generated from the solid electrolyte to provide a negative electrode current collector capable of securing a secondary battery having a high capacity retention rate.

Another aspect of the present invention is to provide a method of manufacturing a negative electrode current collector capable of securing a secondary battery having a high capacity retention rate by suppressing capacity loss of an all-solid secondary battery due to reaction with gas generated from a solid electrolyte. .

Another aspect of the present invention is to provide an all-solid-state secondary battery having a high capacity retention rate by suppressing a capacity loss due to a reaction between a gas generated from a solid electrolyte and a negative electrode current collector.

In addition to the above-mentioned aspects of the present invention, other features and advantages of the present invention are described below, or it will be clearly understood by those skilled in the art from the description.

According to one aspect of the present invention as described above, a copper film having a first side and a second side of the opposite side (copper film); And a first corrosion-resistant layer on the first surface, wherein the first corrosion-resistant layer includes copper oxynitride, and a negative electrode current collector for an all-solid secondary battery is provided.

The copper oxynitride may have a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19).

The first corrosion-resistant layer may have a thickness of 0.1 to 1 μm.

The negative electrode current collector may further include a first antirust layer between the first surface and the first corrosion-resistant layer, and the first anti-rust layer may include chromium (Cr).

The negative electrode current collector may further include a second corrosion resistant layer on the second surface, and the second corrosion resistant layer may include copper oxynitride.

The negative electrode current collector may include a first antirust layer between the first surface and the first corrosion resistant layer; And a second anti-corrosion layer between the second surface and the second corrosion-resistant layer, and the first anti-corrosion layer and the second anti-corrosion layer may include chromium (Cr).

According to another aspect of the invention, forming a copper film by performing electroplating; And forming a corrosion resistant layer on at least one surface of the copper film, wherein the corrosion resistant layer comprises copper oxynitride, and a method for manufacturing a negative electrode current collector for an all-solid secondary battery is provided.

The copper oxynitride may have a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19).

The corrosion-resistant layer may have a thickness of 0.1 to 1 μm.

The corrosion-resistant layer may be formed by performing copper sputtering under an oxygen and nitrogen atmosphere.

The method may further include forming an anti-corrosion layer containing chromium (Cr) on at least one surface of the copper film before forming the anti-corrosion layer, and the anti-corrosion layer may be formed on the anti-corrosion layer. have.

The rust-preventing layer forming step may include immersing the copper film in a rust-preventing solution containing chromium (Cr); Taking out the copper film from the antirust solution; And drying the copper film.

According to another aspect of the invention, the cathode current collector (anode current collector); An anode active material layer on the anode current collector; A solid electrolyte layer on the negative active material layer; A cathode active material layer on the solid electrolyte layer; And a positive electrode current collector on the positive electrode active material layer, wherein the negative electrode current collector includes a copper film and a corrosion resistant layer on the copper film, and the negative active material layer is located on the corrosion resistant layer, and The corrosion resistant layer is provided with an all-solid-state secondary battery comprising copper oxynitride.

The copper oxynitride may have a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19).

The corrosion-resistant layer may have a thickness of 0.1 to 1 μm.

The solid electrolyte layer may include a sulfide-based solid electrolyte.

The general description of the present invention as described above is only for illustrating or describing the present invention, and does not limit the scope of the present invention.

The corrosion resistant layer of the present invention prevents the formation of a copper sulfide (Cu ₂ S/CuS) layer on the surface of the negative electrode current collector due to hydrogen sulfide (H ₂ S) generated when the sulfide-based solid electrolyte reacts with water or moisture. Can.

Therefore, according to the present invention, it is possible to implement an all-solid-state secondary battery having a high capacity retention rate by preventing a sudden drop in the discharge capacity of the all-solid-state secondary battery.

The accompanying drawings are intended to help the understanding of the present invention and constitute a part of the present specification, and exemplify embodiments of the present invention, and describe the principles of the present invention together with a detailed description of the present invention.
1 is a cross-sectional view of an all-solid secondary battery according to an embodiment of the present invention,
Figure 2 is a flow chart illustrating a method of manufacturing a negative electrode current collector for an all-solid secondary battery according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

It will be apparent to those skilled in the art that various changes and modifications of the present invention are possible without departing from the spirit and scope of the present invention. Accordingly, the present invention includes all modifications and variations falling within the scope of the invention and equivalents described in the claims.

In the present specification, when a structure is described as being formed “on” or “below” another structure, such a description may include the case where the structures are in contact with each other as well as when a third structure is interposed between the structures. It should be interpreted as including. However, when the terms "directly above" or "directly below" are used, these structures should be interpreted as being limited to being in contact with each other.

In addition, terms such as “first” and “second” are for distinguishing one component from other components, and the scope of rights should not be limited by these terms.

1 is a cross-sectional view of an all-solid secondary battery 100 according to an embodiment of the present invention.

As illustrated in Figure 1, the all-solid secondary battery 100 of the present invention is a negative electrode current collector 110, a negative electrode active material layer 120 on the negative electrode current collector 110, a solid on the negative electrode active material layer 120 It includes an electrolyte layer 130, a positive electrode active material layer 140 on the solid electrolyte layer 130, and a positive electrode current collector 150 on the positive electrode active material layer 140.

The negative electrode current collector 110 is a current collector including copper (Cu), and together with the negative electrode active material layer 120, constitutes a negative electrode of the all-solid secondary battery 100.

The negative active material layer 120 includes a negative active material commonly used in lithium ion secondary batteries, for example, carbon; Metals of Si, Ge, Sn, Li, Zn, Mg, Cd, Ce, Ni or Fe; An alloy containing the metal; Oxides of the metals; And it may include one or more negative electrode active material selected from the group consisting of a composite active material of the metal and carbon.

According to an embodiment of the present invention, in order to increase the charge and discharge capacity of the all-solid secondary battery 100, the negative active material layer 120 is a composite active material in which Si or Sn is added to a carbon active material of artificial graphite or natural graphite It may include.

In order to improve conductivity, the negative active material layer 120 may further include a conductive assistant.

In addition, in order to realize a full-solid secondary battery 100 capable of high-speed charging and discharging, the anode active material layer 120 may further include a sulfide-based solid electrolyte together with the anode active material. The sulfide-based solid electrolyte in the anode active material layer 120 increases the mobility (ie, ion conductivity) of lithium ions.

The solid electrolyte layer 130 may include a sulfide-based solid electrolyte, an oxide-based solid electrolyte, and an amorphous solid electrolyte as a solid electrolyte.

According to an embodiment of the present invention, the solid electrolyte layer 130 is a Li ₂ SP ₂ S ₅ based electrolyte, Li ₂ SP ₂ S ₅ -P ₂ O ₅ based electrolyte, Li ₂ S-SiS ₂ -Li ₃ PO ₄ series electrolyte, Li ₂ S-SiS ₂ -Li ₄ SiO ₄ series electrolyte, Li ₂ SB ₂ S ₃ -LiI series electrolyte, Li ₂ S-GeS ₂ -Li ₃ PO ₄ series electrolyte, Li ₂ S-GeS _2- P ₂ S ₅ -based electrolyte, Li ₂ S-GeS ₂ -P ₂ O _5- based electrolyte, and the like, including a sulfide-based solid electrolyte having a high ionic conductivity comparable to a conventional liquid electrolyte.

The positive electrode active material layer 140 is a positive electrode active material commonly used in lithium ion secondary batteries, for example, lithium cobalt oxide (LCO), lithium manganese oxide (LMO), lithium nickel-cobalt-aluminum oxide (NCA), lithium Nickel-cobalt-manganese oxide (NCM), and/or lithium iron phosphate (LFP).

In order to improve conductivity, the positive electrode active material layer 140 may further include a conductive assistant.

In addition, in order to realize a full-solid secondary battery 100 capable of high-speed charging and discharging, the positive electrode active material layer 140 may further include a sulfide-based solid electrolyte together with the positive electrode active material. The sulfide-based solid electrolyte in the positive electrode active material layer 140 increases the mobility (ie, ionic conductivity) of lithium ions.

The positive electrode current collector 150 constituting the positive electrode of the all-solid secondary battery 100 together with the positive electrode active material layer 140 includes copper (Cu), nickel (Ni), aluminum (Al), gold (Au), and platinum. (Pt), magnesium (Mg), iron (Fe), titanium (Ti), cobalt (Co), chromium (Cr), zinc (Zn) or the like, or may be formed of an alloy consisting of two or more of the above metals have. According to an embodiment of the present invention, the positive electrode current collector 150 is an aluminum (Al) current collector.

Hereinafter, the negative electrode current collector 110 of the present invention will be described in more detail.

The negative electrode current collector 110 of the present invention includes a copper film 111 including a first surface and a second surface opposite thereto and a first corrosion resistant layer 112a on the first surface. The negative active material layer 120 is positioned on the first corrosion-resistant layer 112a. The first corrosion resistant layer 112a and the negative active material layer 120 may contact each other.

Optionally, as illustrated in FIG. 1, the negative electrode current collector 110 may further include a first anti-rust layer 113a between the first surface and the first corrosion-resistant layer 112a. The first anti-corrosion layer 113a is to prevent corrosion of the copper film 111 until the first corrosion-resistant layer 112a is formed, and may include chromium (Cr).

In the first corrosion-resistant layer 112a, hydrogen sulfide (H ₂ S) generated when the sulfide-based solid electrolyte of the solid electrolyte layer 130 reacts with water or moisture moves to the copper film 111 to move copper (Cu). It is a layer for preventing the formation of a copper sulfide (Cu ₂ S/CuS) layer on the surface of the copper film 111 by reacting with.

The first corrosion resistant layer 112a is such that it does not corrode even if it comes into contact with a sulfide-based solid electrolyte that may be included in the negative electrode active material layer 120 in order to increase the mobility (ie, ion conductivity) of lithium ions. In addition to having high corrosion resistance itself, (ii) the copper foil so as not to be peeled off from the copper foil (copper film + anti-rust layer) during the manufacturing process of the negative electrode current collector 110 or during use of the all-solid secondary battery 100 It should have high adhesion to (iii) and above all, it should have the lowest specific resistance possible to minimize electrical loss.

In order to satisfy all of these requirements, the first corrosion resistant layer 112a of the present invention includes copper oxynitride.

According to an embodiment of the present invention, the copper oxynitride may have a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19). That is, in the copper oxynitride, the atomic percentage (atomic %) of oxygen may be greater than 0 at.% and less than 0.3 at.%, and the atomic percentage of nitrogen may be greater than 0 at.% and less than 0.19 at.%.

The atomic percentage of each of copper (Cu), oxygen (O), and nitrogen (N) of the first corrosion-resistant layer 112a may be measured by Auger Electron Spectroscopy (AES).

According to an embodiment of the present invention, the first corrosion resistant layer 112a has a thickness of 0.1 to 1 μm.

When the thickness of the first corrosion-resistant layer 112a is less than 0.1 μm, corrosion of the copper film 111 by a sulfide-based solid electrolyte and/or hydrogen sulfide (H ₂ S) cannot be properly prevented. On the other hand, if the thickness of the first corrosion resistant layer 112a exceeds 1 μm, even if the specific resistance of copper oxynitride used to form the first corrosion resistant layer 112a is low, significant electrical loss cannot be avoided.

Optionally, as illustrated in FIG. 1, the cathode current collector 110 may further include a second corrosion resistant layer 112b on the second surface of the copper film 111.

The second corrosion resistant layer 112b has a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19) as in the first corrosion resistant layer 112a. Copper oxynitride and may have a thickness of 0.1 to 1 μm.

In addition, the negative electrode current collector 110 may further include a second anti-corrosion layer 113b including chromium (Cr) between the second surface of the copper film 111 and the second corrosion-resistant layer 112b. Can. Like the first anti-corrosion layer 113a, the second anti-corrosion layer 113b prevents the copper film 111 from being corroded until the first anti-corrosion layer 112a and the second anti-corrosion layer 112b are formed. prevent.

Hereinafter, a method of manufacturing the negative electrode current collector 110 for an all-solid-state secondary battery according to an embodiment of the present invention will be described in detail with reference to FIG. 2.

First, a copper film 111 is formed on a rotating drum electrode by performing electroplating (S1).

30 to 60 A/dm ² of rotating drum electrodes and counter electrode plates arranged spaced apart from each other in an electrolyte at 40 to 60° C. containing 50 to 100 g/L copper ions and 50 to 150 g/L sulfuric acid. The electroplating can be performed by energizing at a current density.

Optionally, the electrolyte is at least one organic selected from the group consisting of hydroxyethyl cellulose (HEC), organic sulfide (eg, SPS), organic nitride, glycol-based polymer, and thiourea. Additives and/or chlorine ions may be further included. The content of the organic additive and the content of chlorine ions in the electrolyte solution 20 may be 1 to 10 ppm and 1 to 50 ppm, respectively.

Subsequently, corrosion resistant layers 112a and 112b including copper oxynitride are formed on at least one surface of the copper film 111 (S3 ). As described above, the copper oxynitride may have a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19), and the corrosion resistant layer 112a, 112b) may have a thickness of 0.1 to 1 μm.

The corrosion-resistant layers 112a and 112b are vacuum deposition methods such as sputtering, chemical vapor deposition (CVD), ion beam deposition, pulsed laser deposition, or spray coating ( It may be formed through a wet coating method such as spray coating, spin coating, dip coating, and the like. However, it is preferable to use a vacuum deposition method such as sputtering in that high-quality corrosion-resistant layers 112a and 112b having relatively high density can be obtained by growing a film using high particle energy.

According to an embodiment of the present invention, first and second corrosion resistant layers 112a including copper oxynitride on first and second surfaces of the copper film 111 by performing copper sputtering under an oxygen and nitrogen atmosphere. , 112b).

The atomic percentages (atomic %) of copper (Cu), oxygen (O), and nitrogen (N) of the first corrosion-resistant layer 112a are used to determine the flow rates of oxygen and nitrogen, which are reactive gases supplied into the sputtering chamber. It can be adjusted by changing. An inert gas such as argon (Ar) may be used as a process gas for sputtering.

Optionally, as illustrated in FIG. 2, before forming the corrosion resistant layers 112a and 112b, rustproof layers 113a and 113b may be formed on at least one surface of the copper film 111 (S2). ). In this case, the corrosion resistant layers 112a and 112b are formed on the antirust layers 113a and 113b (S3).

According to an embodiment of the present invention, the copper film 111 formed on the rotating drum electrode, through a roll-to-roll process, comprises 0.5 to 3.5 g/L of chromium (Cr). After immersing in the rust preventive solution at 20 to 60° C., the first rust preventive layer (113a) and the second rust preventive layer (113b) are placed on the first and second surfaces of the copper film 111 by drying from the antirust solution. Each can be formed.

Hereinafter, the present invention will be described in detail through examples and comparative examples. However, the following examples are only to aid the understanding of the present invention, and the scope of the present invention is not limited to these embodiments.

Example 1

A copper film having a thickness of about 10 µm was formed on the rotating drum electrode by energizing the rotating drum electrode and the counter electrode plate disposed spaced apart from each other in the copper sulfate electrolyte at a current density of 50 A/dm ² . The electrolytic solution was maintained at about 55°C while electroplating was performed. The copper film was immersed in the antirust solution and then dried. Subsequently, argon (Ar) gas as a processing gas was injected into the sputtering chamber at a flow rate of 200 sccm, and oxygen (O ₂ ) gas and nitrogen (N ₂ ) gas as a reaction gas were respectively 30 sccm and 50 sccm. Sputtering with a power of 200 W using a copper (Cu) target having a purity of 99.999% while injecting it into the chamber at a flow rate creates an internal corrosion layer made of copper oxynitride of the formula Cu ₇₁ O ₁₄ N ₁₅ on the copper film. Formed.

The atomic percentage of each of the copper (Cu), oxygen (O) and nitrogen (N) of the corrosion resistant layer was measured by Auger Electron Spectroscopy (AES) [natural oxide on the surface of the cathode current collector] Measure after removing it].

A negative electrode was prepared by coating the negative electrode active material on the thus prepared negative electrode current collector using a blade coater and drying it in a convection oven at about 100° C. for 30 minutes. The negative active material is an ultrasonic dispersion of natural graphite having an average particle size of 15 μm, a carbon-based conductive material having an average particle size of 100 nm, and a Li ₂ SP ₂ S ₅ based solid electrolyte (75 Li ₂ S 25 P ₂ S ₅ ) having an average particle size of 1.5 μm. It was prepared by stirring with a device.

A positive electrode was prepared by coating a positive electrode current collector on an aluminum (Al) foil using a blade coater and drying it in a convection oven at about 100° C. for 30 minutes. The cathode active material binder, and an average particle size of 4㎛ _{LiNi 1/3 Co 1/3} Mn 1/3 O 2, average particle size of the carbon-based conductive material of 100nm, and an average particle size of 1.5㎛ Li ₂ SP ₂ S ₅ based solid electrolyte (75 Li ₂ S 25 P ₂ S ₅ ) was prepared by stirring with an ultrasonic dispersion device.

Subsequently, the positive electrode, a Li ₂ SP ₂ S ₅ based solid electrolyte (75 Li ₂ S 25 P ₂ S ₅ ) having an average particle size of 1.5 μm, and the negative electrode were sequentially stacked in a cylindrical press mold, and then 600 MPa at about 150° C. It was pressed for 5 minutes under the pressure of. After compression, the all-solid-state secondary battery was completed by maintaining the laminate under a pressure of 60 MPa.

Example 2

By controlling the flow rates of oxygen (O ₂ ) gas and nitrogen (N ₂ ) gas injected into the chamber during the copper sputtering, an internal corrosion layer made of copper oxynitride of the formula Cu ₇₈ O ₉ N ₁₃ was formed on the copper film. An all-solid secondary battery was completed in the same manner as in Example 1, except that.

Example 3

By controlling the flow rates of oxygen (O ₂ ) gas and nitrogen (N ₂ ) gas injected into the chamber during the copper sputtering, an internal corrosion layer made of copper oxynitride of the formula Cu ₇₂ O ₁₈ N ₁₀ was formed on the copper film. An all-solid secondary battery was completed in the same manner as in Example 1, except that.

Comparative Example 1

An all-solid secondary battery was completed in the same manner as in Example 1, except that the corrosion resistant layer was not formed.

Comparative Example 2

All solid secondary in the same manner as in Example 1, except that a copper oxide film of the formula Cu ₆₉ O ₃₁ was formed on the copper film by injecting only oxygen (O ₂ ) gas into the chamber during the copper sputtering. The battery was completed.

Comparative Example 3

All solid secondary in the same manner as in Example 1, except that a copper nitride film of formula Cu ₈₁ N ₁₉ was formed on the copper film by injecting only nitrogen (N ₂ ) gas into the chamber during the copper sputtering. The battery was completed.

For each of the solid-state secondary batteries of the examples and comparative examples prepared as above, charge until the voltage reaches 4.1V, discharge to 2.5V at 1mA, and measure the primary discharge capacity (mAh/g) After performing the charging and discharging 20 times repeatedly, the 20th discharge capacity (mAh/g) was measured, and the capacity retention rate was calculated according to Equation 1 below. Table 1 shows the measurement results.

* Equation 1: Capacity retention rate (%) = (20th discharge capacity/1st discharge capacity)×100

Table 1 shows the primary discharge capacity (mAh/g), secondary discharge capacity (mAh/g), and capacity retention rate of each all-solid-state secondary battery.

Cathode current collector corrosion resistant layer All-solid secondary battery matter Chemical formula 1st discharge capacity (mAh/g) 20th discharge capacity (mAh/g) Capacity retention rate (%) Example 1 Copper oxynitride Cu ₇₁ O ₁₄ N ₁₅ 16.0 14.6 91 Example 2 Copper oxynitride Cu ₇₈ O ₉ N ₁₃ 18.0 16.7 93 Example 3 Copper oxynitride Cu ₇₂ O ₁₈ N ₁₀ 13.0 11.4 88 Comparative Example 1 - - 11.0 9.4 85 Comparative Example 2 Copper oxide Cu ₆₉ O ₃₁ 3.9 3.5 89 Comparative Example 3 Copper nitride Cu ₈₁ N ₁₉ 9.7 8.1 84

As can be seen from Table 1, all solid secondary batteries (Example 1-3) in which the corrosion resistant layer of the negative electrode current collector was formed of copper oxynitride, had a high capacity retention rate of 88% or more due to the excellent corrosion resistance of copper oxynitride. In addition, it exhibited a high primary discharge capacity of 13.0 mAh/g or higher due to the relatively high ionic conductivity of copper oxynitride. On the other hand, an all-solid secondary battery (comparative to that in which the negative electrode current collector does not have a corrosion resistant layer) Example 1) exhibited a relatively low primary discharge capacity of 11.0 mAh/g and a low capacity retention rate of 85%.

On the other hand, the all-solid secondary battery in which the corrosion resistant layer of the negative electrode current collector was formed of copper oxide (Comparative Example 2) showed a poor capacity retention rate of 89%, but it was very difficult to use itself as a battery due to the low ionic conductivity of copper oxide. It showed a low primary discharge capacity (3.9 mAh/g).

In addition, the all-solid secondary battery in which the corrosion resistant layer of the negative electrode current collector was formed of copper nitride (Comparative Example 3) showed not only a low primary discharge capacity of 9.7 mAh/g due to low ion conductivity of copper nitride, but also its capacity retention rate. It was only 84%. That is, the all-solid secondary battery in which the corrosion-resistant layer of the negative electrode current collector was formed of copper nitride (Comparative Example 3) showed overall worse performance than the all-solid-state secondary battery (Comparative Example 1) in which the negative electrode current collector had no corrosion-resistant layer.

100: all-solid secondary battery 110: negative electrode current collector
111: copper film 112a, 112b: first and second corrosion-resistant layer
113a, 113b: first and second antirust layer 120: negative electrode active material layer
130: solid electrolyte layer 140: positive electrode active material layer
150: anode current collector

Claims (16)

A copper film having a first side and a second side of the opposite side; And
A first corrosion-resistant layer on the first side
Including,
The first corrosion-resistant layer includes copper oxynitride,
Cathode current collector for all-solid secondary battery. According to claim 1,
The copper oxynitride has a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19),
Cathode current collector for all-solid secondary battery. According to claim 1,
The first corrosion-resistant layer has a thickness of 0.1 to 1 ㎛,
Cathode current collector for all-solid secondary battery. According to claim 1,
Further comprising a first antirust layer (antirust layer) between the first surface and the first corrosion-resistant layer,
The first rust-prevention layer includes chromium (Cr),
Cathode current collector for all-solid secondary battery. According to claim 1,
Further comprising a second corrosion-resistant layer on the second surface,
The second corrosion-resistant layer includes copper oxynitride,
Cathode current collector for all-solid secondary battery. The method of claim 5,
A first anti-corrosion layer between the first surface and the first corrosion-resistant layer; And
A second anti-corrosion layer between the second surface and the second corrosion-resistant layer
Further comprising,
The first rustproof layer and the second rustproof layer include chromium (Cr),
Cathode current collector for all-solid secondary battery. Forming a copper film by performing electroplating; And
Forming a corrosion resistant layer on at least one side of the copper film
Including,
The corrosion-resistant layer includes copper oxynitride,
Method for manufacturing a negative electrode current collector for an all-solid secondary battery. The method of claim 7,
The copper oxynitride has a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19),
Method for manufacturing a negative electrode current collector for an all-solid secondary battery. The method of claim 7,
The corrosion-resistant layer has a thickness of 0.1 to 1 ㎛,
Method for manufacturing a negative electrode current collector for an all-solid secondary battery. The method of claim 7,
The corrosion resistant layer is formed by performing copper sputtering under an oxygen and nitrogen atmosphere,
Method for manufacturing a negative electrode current collector for an all-solid secondary battery. The method of claim 7,
Before forming the corrosion-resistant layer, further comprising the step of forming an anti-corrosion layer containing chromium (Cr) on at least one surface of the copper film,
The corrosion-resistant layer is formed on the anti-corrosion layer,
Method for manufacturing a negative electrode current collector for an all-solid secondary battery. The method of claim 11,
The anti-rust layer forming step,
Immersing the copper film in an antirust solution containing chromium (Cr);
Taking out the copper film from the antirust solution; And
Drying the copper film
Containing,
Method for manufacturing a negative electrode current collector for an all-solid secondary battery. Anode current collector;
An anode active material layer on the anode current collector;
A solid electrolyte layer on the negative active material layer;
A cathode active material layer on the solid electrolyte layer; And
Cathode current collector on the cathode active material layer
Including,
The negative electrode current collector includes a copper film and a corrosion resistant layer on the copper film,
The anode active material layer is located on the corrosion-resistant layer,
The corrosion-resistant layer includes copper oxynitride,
All-solid secondary battery. The method of claim 13,
The copper oxynitride has a chemical formula of Cu _x O _y N _z (x+y+z=100, 0<y≤30, 0<z≤19),
All-solid secondary battery. The method of claim 13,
The corrosion-resistant layer has a thickness of 0.1 to 1 ㎛,
All-solid secondary battery. The method of claim 13,
The solid electrolyte layer includes a sulfide-based solid electrolyte,
All-solid secondary battery.

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