KR20240035326A - Water-based slurry composition for positive electrode, positive electrode and lithium secondary battery prepared therefrom - Google Patents

Abstract

One aspect of the present invention relates to an aqueous slurry composition for a positive electrode that can replace the existing positive electrode slurry composition using organic solvents and fluorine-based polymers. The aqueous slurry composition for a positive electrode according to one aspect is a metal salt containing a cosmotropic anion. and an aqueous electrolyte containing water, a positive electrode active material, and an aqueous polymer.

Description

Water-based slurry composition for positive electrode, positive electrode and lithium secondary battery prepared therefrom

The present invention relates to an aqueous slurry composition for a positive electrode that ensures chemical stability with a positive electrode active material vulnerable to moisture, and to a positive electrode and lithium secondary battery manufactured therefrom.

The production of electrodes for existing lithium secondary batteries is based on carcinogenic organic solvents and fluorine-based polymers that are difficult to recycle. If this is replaced with an aqueous process using water and cellulose-based polymers, it is not only environmentally friendly but also maximizes productivity, so research on the aqueous process for electrode manufacturing is actively underway.

However, side reactions between water and existing electrode active materials cause instability of the electrode active material, increase the basicity of water and cause corrosion of the current collector, which significantly reduces battery performance and lifespan characteristics. Various attempts, such as acid addition and current collector coating, have been reported as a solution to this problem, but the root cause, the instability of the active material in the water system, has not been solved. In particular, the use of high-capacity positive electrode active materials such as high-nickel lithium metal oxide has not been resolved. In this case, it is more difficult to apply to water-based processes due to its high sensitivity to moisture.

Republic of Korea Patent Publication No. 10-2022-0120551 (2022.08.30.)

One aspect of the present invention is to provide an aqueous slurry composition for a positive electrode that can replace a positive electrode slurry composition using existing organic solvents and fluorine-based polymers by ensuring the stability of the positive electrode active material in the water system.

Another aspect of the present invention is to provide a positive electrode manufactured from the aqueous slurry composition for positive electrode and a lithium secondary battery containing the same.

One aspect of the present invention is an aqueous electrolyte containing water and a metal salt containing cosmotropic anions; positive electrode active material; and an aqueous polymer. It provides an aqueous slurry composition for a positive electrode, including a water-based slurry composition.

The cosmotropic anions are SO ₄ ^2- , CH ₃ COO ^- , C ₂ F ₃ O ₂ ^- (TFA ^- ), Cl ^- , NO ₃ ^- , BF ₄ ^- , (PO ₄ ) ^3- and CF ₃ O ₃ S. ^- It may be selected from (OTf ^- ).

The metal salt may contain a cation selected from Li ⁺ , Na ⁺ , K ⁺ , Mg ²⁺ , Al ³⁺ and Zn ²⁺ .

The metal salt may be lithium sulfate (Li ₂ SO ₄ ), sodium sulfate (Na ₂ SO ₄ ), magnesium sulfate (MgSO ₄ ), zinc sulfate (ZnSO ₄ ), lithium phosphate (Li ₃ PO ₄ ), or a combination thereof.

The aqueous electrolyte may contain a metal salt at a molar concentration of 0.1 to 2.0.

The content of the positive electrode active material relative to the total weight of the aqueous slurry composition for the positive electrode may be 40 to 60% by weight.

The aqueous electrolyte and the aqueous polymer may be included in a weight ratio of 1:0.01 to 0.1.

The water-based polymer may be cellulose, polyacrylic acid, polyacrylamide, polyacrylonitrile, polyvinyl alcohol, polyvinyl acetate, polyvinylpyrrolidine, polyethylene, polystyrene, polyurethane, styrene-butadiene rubber, or a combination thereof. there is.

The aqueous slurry composition for a positive electrode according to one aspect may further include a conductive material.

Another aspect of the present invention is a positive electrode current collector; It provides a positive electrode comprising a positive electrode active material layer prepared from the above-described aqueous slurry composition for positive electrode on one or both sides of the positive electrode current collector.

Another aspect of the present invention provides a lithium secondary battery including the above-described positive electrode.

A method for manufacturing a positive electrode according to an aspect of the present invention includes preparing an aqueous electrolyte containing water and a metal salt containing cosmotropic anions; Preparing an aqueous slurry composition for a positive electrode by mixing a lithium positive electrode active material and an aqueous polymer with the aqueous electrolyte; and forming a positive electrode active material layer by applying the aqueous slurry composition for positive electrode to one surface of the positive electrode current collector and heat treating it.

The heat treatment may be performed at a temperature of 25 to 120°C.

The aqueous slurry composition for a positive electrode according to an aspect of the present invention can ensure the chemical stability of a positive electrode active material that is vulnerable to moisture even in an aqueous system. Specifically, the aqueous slurry composition for a positive electrode according to one aspect can suppress pH changes caused by chemical side reactions at the interface between the positive electrode active material and water, and through this, a positive electrode with a stable interface structure and excellent charge and discharge performance can be manufactured. . In particular, the aqueous slurry composition for a positive electrode according to one embodiment can be applied to high-capacity positive electrode active materials such as high-nickel lithium metal oxide, which is very vulnerable to moisture.

In addition, the aqueous slurry composition for a positive electrode according to one aspect is not only environmentally friendly, but can also significantly improve electrode manufacturing productivity. Specifically, it is harmless to the human body and the environment because it does not use organic solvents and fluorine-based polymers, the materials used are very inexpensive compared to existing organic solvent processes, and the solvent recovery process can be shortened, significantly reducing production costs.

Figure 1 is a schematic diagram of the aqueous slurry composition for an anode according to Example 1 and Comparative Example 1.

Unless otherwise defined herein, all technical and scientific terms have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. The terminology used in the description herein is merely to effectively describe particular embodiments and is not intended to limit the invention.

As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly dictates otherwise.

Throughout this specification, “includes,” “comprises,” “contains,” or “has” an element does not exclude other elements, but rather includes other elements, unless specifically stated to the contrary. It means that it can be done, and does not exclude additional elements, materials or processes not listed.

Numerical ranges as used herein include lower and upper limits and all values within that range, increments logically derived from the shape and width of the range being defined, all doubly defined values, and upper and lower limits of numerical ranges defined in different forms. Includes all possible combinations of Unless otherwise specified herein, values outside the numerical range that may occur due to experimental error or rounding of values are also included in the defined numerical range.

Unless otherwise defined herein, when a part of a layer, film, thin film, region, plate, etc. is said to be “on” or “on” another part, this means not only “directly on” the other part, but also intermediate thereto. Also includes cases where there is another part.

Hereinafter, the present disclosure will be described in detail. However, this is merely illustrative and the present disclosure is not limited to the specific embodiments described by way of example.

One aspect of the present invention provides an aqueous slurry composition for a positive electrode that can ensure the chemical stability of a positive electrode active material vulnerable to moisture.

Specifically, an aqueous slurry composition for a positive electrode according to one aspect includes an aqueous electrolyte containing a metal salt containing a kosmotropic anion and water; positive electrode active material; And it may include a water-based polymer.

That is, the aqueous slurry composition for a positive electrode according to one aspect uses a combination of an aqueous electrolyte and an aqueous polymer containing a metal salt containing a cosmotropic anion, thereby ensuring stability for a positive electrode active material with high sensitivity to moisture, In particular, the aqueous slurry composition for a positive electrode according to one aspect may be applicable to high-capacity positive electrode active materials such as high-nickel lithium metal oxide, which is very vulnerable to moisture.

The cosmotropic anion refers to an anion with high kosmotropicity, and may refer to an anion with higher kosmotropicity than bis(trifluoromethanesulfonyl)imide (TFSI ^- ), and water molecules It can stabilize the water structure due to its strong interaction with Through this, the activity of water molecules can be reduced, the stability of the positive electrode active material can be secured by effectively suppressing the reaction between the positive electrode active material and water molecules, and a positive electrode with a stable interface structure and excellent charge/discharge performance can be produced. It can be manufactured.

The cosmotropic anion is, for example, SO ₄ ^2- , ^OAc- , C ₂ F ₃ ^O _2- (TFA- ⁾ , Cl- ^, NO _3- , BF ^{4- ,} ( _{PO 4 )} ^3- , CF ₃ O It may be ₃ S ^- (OTf ^- ) or a combination thereof, and specifically, it may be SO ₄ ^2- or (PO ₄ ) ^3- , and the stability of the positive electrode active material can be further improved. The cation of the metal salt according to one aspect is not particularly limited as long as it is a metal cation that pairs with the kosmotpic anion, but for example, Li ⁺ , Na ⁺ , K ⁺ , Mg ²⁺ , Al ³⁺ , Zn ²⁺ , or It may be a combination of these, and may be an alkali metal cation, for example, Li ⁺ or Na ⁺ .

Metal salts containing cosmotropic anions according to one aspect include, for example, lithium sulfate (Li ₂ SO ₄ ), sodium sulfate (Na ₂ SO ₄ ), magnesium sulfate (MgSO ₄ ), zinc sulfate (ZnSO ₄ ), or phosphoric acid. It may be lithium (Li ₃ PO ₄ ), and more specifically, it may be lithium sulfate (Li ₂ SO ₄ ), sodium sulfate (Na ₂ SO ₄ ), or magnesium sulfate (MgSO ₄ ), and the reaction between the positive electrode active material and water molecules may be further reduced. It can be suppressed effectively.

The aqueous electrolyte may contain 0.1 mol or more, 0.5 mol or more, or 5.0 mol or less, 3.0 mol or less, 2.0 mol or less, or 1.0 mol or less, specifically, 0.1 to 5.0 mol, 0.1 to 3.0 mol. , may be included in a concentration of 0.1 to 2.0 mol, 0.5 to 2.0 mol, or 0.5 to 1.0 mol, and the stability of the positive electrode active material against moisture can be further improved.

The content of the positive electrode active material relative to the total weight of the positive electrode slurry composition may be 40 to 70% by weight, 40 to 60% by weight, or 40 to 50% by weight.

The aqueous electrolyte and the aqueous polymer may be included in a weight ratio of 1:0.01 to 0.1, or 0.01 to 0.05.

If the above content is satisfied, it is preferred because it can further improve battery performance and lifespan characteristics in the future, but is not necessarily limited thereto.

The water-based polymer is not particularly limited as long as it is commonly used in the relevant technical field, but non-limiting examples include cellulose, polyacrylic acid, polyacrylamide, polyacrylonitrile, polyvinyl alcohol, polyvinyl acetate, and polyvinyl chloride. It may be rollidine, polyethylene, polystyrene, polyurethane, styrene-butadiene rubber, or a combination thereof. More specifically, it may be cellulose, polyacrylic acid, or a combination thereof, and the cellulose may include carboxymethyl cellulose, methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose.

The positive electrode active material may be a typical positive electrode active material used in this technical field, and non-limiting examples include lithium cobaltate composite oxide (LiCoO ₂ ), spinel crystalline lithium manganate composite oxide (LiMn ₂ O ₄ ), and manganese. Lithium acid complex oxide (LiMnO ₂ ), nickel acid lithium complex oxide (LiNiO ₂ ), lithium iron phosphate (LiFePO ₄ ), lithium manganese phosphate (LiMnPO ₄ ), lithium cobalt phosphate (LiCoPO ₄ ), lithium pyrophosphate Iron (iron pyrophosphate; Li ₂ FeP ₂ O ₇ ), lithium niobate composite oxide (LiNbO ₂ ), lithium iron acid composite oxide (LiFeO ₂ ), lithium magnesium acid composite oxide (LiMgO ₂ ), lithium cuprate composite oxide (LiCuO _{2 )} ), lithium zincate complex oxide (LiZnO ₂ ), lithium molybdate complex oxide (LiMoO ₂ ), lithium tantalum acid complex oxide (LiTaO ₂ ), lithium tungstate complex oxide (LiWO ₂ ), perlithium permanganese nickel cobalt Composite oxide (xLi ₂ MnO ₃ (1-x)LiMn1-y-zNiyCozO ₂ ), lithium nickel cobalt aluminum composite oxide (LiNi _0.8 Co _0.15 Al _0.05 O ₂ ), manganese nickel oxide (LiNi _0.5 Mn _1.5 O ₄ ), lithium Nickel cobalt manganese complex oxide (LiNi _0.33 Co _0.33 Mn _0.33 O ₂ , LiNi _0.4 Co _0.2 Mn _0.4 O ₂ , LiNi _0.5 Co _0.2 Mn _0.3 O ₂ , LiNi _0.6 Co _0.2 Mn _0.2 O ₂ , LiNi _0.7 Co _0.15 Mn _{0. 15} O ₂ , LiNi _0.8 Co _0.1 Mn _0.1 O ₂ ), etc., but is not limited thereto.

In particular, the aqueous slurry composition for a positive electrode according to one embodiment includes a high-capacity positive electrode material such as lithium nickel cobalt manganese composite oxide containing nickel content of 60 mol% or more, for example, NCM811 (LiNi _0.8 Co _0.1 Mn _0.1 O ₂ ), etc. It has the advantage of excellent miscibility.

The aqueous slurry composition for the positive electrode may further include a conductive material.

The conductive material is not particularly limited as long as it is commonly used in the relevant technical field, but as a non-limiting example, it may be a carbon-based conductive material, and the carbon-based conductive material includes a point-shaped carbon-based conductive material, a linear carbon-based conductive material, and a plate-shaped carbon-based conductive material. It may include a conductive material or a mixture thereof. Point-shaped carbon-based conductive materials include acetylene black, Ketjen black, channel black, furnace black, lamp black, thermal black, and carbon black, and linear carbon-based conductive materials include carbon nanotubes and conductive carbon fiber. Examples of plate-shaped carbon-based conductive materials include graphene (including GRO).

Another aspect of the present invention provides a positive electrode manufactured from the above-described aqueous slurry composition for positive electrode.

Specifically, the positive electrode according to the above aspect includes a positive electrode current collector; and a positive electrode active material layer formed on at least one side of the positive electrode current collector and manufactured from an aqueous slurry composition for a positive electrode according to an embodiment.

A non-limiting example of the positive electrode current collector may be aluminum, copper, nickel, titanium, zinc, carbon, or a combination thereof, and may specifically be aluminum.

The positive electrode according to one aspect includes preparing an aqueous electrolyte containing water and a metal salt containing cosmotropic anions; Preparing an aqueous slurry composition for a positive electrode by mixing a positive electrode active material and an aqueous polymer with the aqueous electrolyte; and forming a positive electrode active material layer by applying the aqueous slurry composition for a positive electrode to one surface of a positive electrode current collector and heat treating it.

The application can be performed using a conventional application method, and specific examples include spray coating, dip coating, spin coating, gravure coating, slot die coating, doctor blade coating, roll coating, inkjet printing, slot die coating, lexography printing, Examples include, but are not limited to, screen printing, electrostatic hydraulic printing, micro contact printing, imprinting, reverse offset printing, and bar-coating.

The heat treatment may be performed at a temperature of 25 to 120°C, or 25 to 60°C.

Another aspect of the present invention provides a lithium secondary battery including the above-described positive electrode.

Hereinafter, a lithium secondary battery according to one aspect will be described using conventional manufacturing methods and materials in the art, except that it includes a positive electrode manufactured from the aqueous slurry composition for positive electrode according to one aspect. Of course, it can be manufactured with a structure known in the art.

A lithium secondary battery according to one aspect may include a positive electrode, a negative electrode, and an electrolyte prepared from the aqueous slurry composition for positive electrode.

The negative electrode may include a negative electrode current collector and a negative electrode active material layer formed on the negative electrode current collector.

Non-limiting examples of the negative electrode current collector may be selected from foil made of copper, gold, nickel, copper alloy, or a combination thereof. The anode active material layer is made of soft carbon, hard carbon, artificial graphite, natural graphite, expanded graphite, carbon fiber, non-graphitic carbon, carbon black, carbon nanotubes, acetylene black, Ketjen black, graphene, fullerene, activated carbon, and mesocarbon. Any one carbon selected from microbeads; Any one metal selected from silicon, tin, lithium, aluminum, silver, bismuth, indium, germanium, lead, platinum, titanium, zinc, manganese, cadmium, cerium, copper, cobalt, nickel and iron; An alloy containing two or more of the above metals; and one or more oxides of the above metals; it may be any one or two or more selected from the group consisting of, preferably It may be lithium metal, but is not limited thereto.

The electrolyte may be a liquid electrolyte, a solid electrolyte, or a combination thereof, and specifically may be a liquid electrolyte, and the liquid electrolyte may include a non-aqueous organic solvent and a lithium salt.

The non-aqueous organic solvent may be selected from cyclic carbonate-based solvents, linear carbonate-based solvents, and mixed solvents thereof, and the cyclic carbonate-based solvents include ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, and vinylethylene. It may be selected from the group consisting of carbonate, fluoroethylene carbonate, and mixtures thereof, and the linear carbonate-based solvent is dimethyl carbonate, diethyl carbonate, dipropyl carbonate, ethylmethyl carbonate, methylpropyl carbonate, methyl isopropyl carbonate, and ethyl. It may be selected from the group consisting of propyl carbonate and mixtures thereof.

The lithium salts include LiPF ₆ , LiBF ₄ , LiSbF ₆ , LiAsF ₆ , LiClO ₄ , LiCF ₃ SO ₃ , LiN(SO ₂ CF ₃ ) ₂ , LiN(SO ₂ C ₂ F ₅ ) ₂ , LiC(SO ₂ CF ₃ ) One or two or more types selected from the group consisting of ₃ , LiN(SO ₃ CF ₃ ) ₂ , LiC ₄ F ₉ SO ₃ , LiAlO ₄ , LiAlCl ₄ , LiCl and LiI can be used, but are limited to this. It doesn't work. The concentration of the lithium salt may be 0.6 M to 2.0 M.

In addition, the lithium secondary battery according to one aspect may further include a separator, and the separator is not limited as long as it is commonly used in the relevant technical field, but non-limiting examples include, for example, glass fiber, polyester, It may be selected from polyethylene, polypropylene, polytetrafluoroethylene, or a combination thereof, may be in the form of non-woven fabric or woven fabric, and may optionally be used in a single-layer or multi-layer structure.

The shape of the lithium secondary battery according to one aspect is not particularly limited as long as it can accommodate the positive electrode, negative electrode, separator, and electrolyte, and may be, for example, cylindrical, coin, pouch, flat, or laminate.

Hereinafter, the above-described implementation example will be described in more detail through examples. However, the following examples are for illustrative purposes only and do not limit the scope of rights.

[Example 1]

Preparation of aqueous slurry composition for anode

An aqueous electrolyte was prepared by mixing lithium sulfate (Li ₂ SO ₄ ) with water at a molar concentration of 0.5. In the aqueous electrolyte, a positive electrode having a weight ratio of 94/3/1.5/1.5 of positive electrode active material (LiNi _0.8 Mn _0.1 Co _0.1 O ₂ , NCM811)/carbon black/carboxymethyl cellulose (CMC)/polyacrylic acid (PAA) is added. An aqueous slurry composition for anode was prepared by mixing so that the ash content was 55% by weight.

Manufacturing of anode

The aqueous slurry composition for the positive electrode was applied to an 18 ㎛ aluminum (Al) current collector using a doctor blade, and vacuum dried at 40°C for 12 hours to form a positive electrode active material layer with a thickness of 80 ㎛.

Manufacturing of lithium secondary batteries

The positive electrode prepared above and the negative electrode in which 100 ㎛ thick lithium metal was rolled on an 8 ㎛ thick copper foil current collector were used as counter electrodes, and a polyethylene separator (Donen Co., Ltd., F20BHE, thickness = 16 ㎛) was placed between the positive electrode and the negative electrode. After interposition, electrolyte (1M hexafluorophosphate (LiPF ₆ ), ethylene carbonate/dimethyl carbonate/vinylene carbonate = 1:1:0.02 by volume) was injected to prepare a coin cell type battery.

[Example 2 and 3]

When preparing the aqueous electrolyte, the same procedure as Example 1 was carried out, except that the concentration of lithium sulfate was changed to 1.0 molar concentration and 2.0 molar concentration, respectively.

[Example 4 and 5]

When preparing the aqueous electrolyte, the same procedure as Example 1 was carried out, except that sodium sulfate (Na ₂ SO ₄ ) and magnesium sulfate (MgSO ₄ ) were used instead of lithium sulfate, respectively.

[Comparative Example 1]

When preparing the aqueous slurry composition for the positive electrode, the same procedure as Example 1 was carried out, except that pure water was used instead of the aqueous electrolyte containing lithium sulfate.

[Comparative Example 2]

When preparing the aqueous electrolyte, the same procedure as Example 1 was carried out, except that LiTFSI was used instead of lithium sulfate (Li ₂ SO ₄ ).

[Comparative Example 3]

The same procedure as Example 1 was carried out, except that N-methylpyrrolidone (NMP) was used instead of the aqueous electrolyte, and polyvinylidene fluoride (PVdF) was used instead of CMC and PAA as the binder.

<Evaluation example>

1. Evaluation of life characteristics

The room temperature lifespan characteristics of the lithium secondary batteries manufactured in the examples and comparative examples above were analyzed. Specifically, the initial charge/discharge capacity of each lithium secondary battery was observed at room temperature (25°C) in a voltage range of 3.00 to 4.25 V and a current of 0.1 C (= 0.4 mA/cm2), and 0.2 C/0.5 C ( = 2.0 mA/cm2), the charging/discharging was repeated 200 times. Thereafter, the melt capacity retention rate (%) was calculated as the percentage of the discharge capacity in 200 cycles divided by the discharge capacity in 1 cycle, and is listed in Table 1 below.

Example Comparative example One 2 3 One 2 3 Capacity maintenance rate (%) 89.4 88.3 86.2 77.7 74.4 91.3

Referring to Table 1, the lithium secondary battery containing a positive electrode manufactured from the aqueous slurry composition for positive electrode according to Examples 1 to 3 of the present invention is a lithium secondary battery containing a positive electrode manufactured using an organic solvent and a fluorine-based polymer binder. It can be seen that a capacity maintenance rate similar to that of the secondary battery (Comparative Example 3) is achieved. In addition, it was confirmed that the lithium secondary battery including the positive electrode according to Examples 4 and 5 also had excellent capacity retention rate. On the other hand, the lifespan characteristics of the lithium secondary batteries of Comparative Examples 1 and 2 were all deteriorated. That is, the aqueous slurry composition for a positive electrode according to one aspect of the present invention can ensure the stability of a positive electrode active material that is vulnerable to moisture and can provide a positive electrode with a stable interface structure and excellent charge and discharge performance.

Figure 1 is a schematic diagram of the aqueous slurry composition for an anode according to Example 1 and Comparative Example 1. In the case of Comparative Example 1, it can be seen that since it does not contain kosmotropic anions, the activity of water is high, causes a side reaction between water and the positive electrode active material, increases the basicity of water, and causes corrosion of the current collector. On the other hand, in Example 1, by reducing the activity of water, the reactivity of the NCM811 positive electrode active material, which is vulnerable to moisture, to water can be suppressed and pH changes can be suppressed, thereby providing a positive electrode with a stable interface structure and excellent charge and discharge performance. can be manufactured.

As described above, the present invention has been described in terms of limited embodiments, but these are only provided to facilitate a more general understanding of the present invention, and the present invention is not limited to the above embodiments, and is based on common knowledge in the field to which the present invention pertains. Anyone who has the knowledge can make various modifications and variations from this description.

Accordingly, the spirit of the present invention should not be limited to the described embodiments, and the scope of the patent claims described below as well as all modifications that are equivalent or equivalent to the scope of this patent claim shall fall within the scope of the spirit of the present invention. .

Claims (13)

An aqueous electrolyte containing water and a metal salt containing cosmotropic anions; positive electrode active material; and an aqueous polymer; an aqueous slurry composition for a positive electrode. According to paragraph 1,
The cosmotropic anions are SO ₄ ^2- , CH ₃ COO ^- , C ₂ F ₃ O ₂ ^- (TFA ^- ), Cl ^- , NO ₃ ^- , BF ₄ ^- , (PO ₄ ) ^3- and CF ₃ O ₃ S. ^- (OTf ^- ), an aqueous slurry composition for an anode selected from the group. According to paragraph 1,
The metal salt is an aqueous slurry composition for a positive electrode containing a cation selected from Li ⁺ , Na ⁺ , K ⁺ , Mg ²⁺ , Al ³⁺ and Zn ²⁺ . According to paragraph 1,
The metal salt is lithium sulfate (Li ₂ SO ₄ ), sodium sulfate (Na ₂ SO ₄ ), magnesium sulfate (MgSO ₄ ), zinc sulfate (ZnSO ₄ ), lithium phosphate (Li ₃ PO ₄ ), or a combination thereof for the positive electrode. Water-based slurry composition. According to paragraph 1,
The aqueous electrolyte is an aqueous slurry composition for a positive electrode containing a metal salt at a molar concentration of 0.1 to 2.0. According to paragraph 1,
An aqueous slurry composition for a positive electrode, wherein the content of the positive electrode active material is 40 to 60% by weight relative to the total weight of the aqueous slurry composition for the positive electrode. According to paragraph 1,
An aqueous slurry composition for a positive electrode, wherein the aqueous electrolyte and the aqueous polymer are contained in a weight ratio of 1:0.01 to 0.1. According to paragraph 1,
The water-based polymer is cellulose, polyacrylic acid, polyacrylamide, polyacrylonitrile, polyvinyl alcohol, polyvinyl acetate, polyvinylpyrrolidine, polyethylene, polystyrene, polyurethane, styrene-butadiene rubber, or a combination thereof, Aqueous slurry composition for anode. According to paragraph 1,
The aqueous slurry composition for a positive electrode further includes a conductive material. positive electrode current collector; A positive electrode comprising a positive electrode active material layer prepared from the aqueous slurry composition for positive electrode according to any one of claims 1 to 9 on one or both sides of the positive electrode current collector. A lithium secondary battery comprising the positive electrode according to claim 10. Preparing an aqueous electrolyte containing water and a metal salt containing cosmotropic anions;
Preparing an aqueous slurry composition for a positive electrode by mixing a lithium positive electrode active material and an aqueous polymer with the aqueous electrolyte; and
A method of manufacturing a positive electrode comprising: applying the aqueous slurry composition for a positive electrode to one surface of a positive electrode current collector and heat treating it to form a positive electrode active material layer. According to clause 12,
A method of manufacturing a positive electrode, wherein the heat treatment is performed at a temperature of 25 to 120°C.