Cathode slurry composition for all-solid-state battery and preparation method thereof

Abstract

The invention relates to a cathode slurry composition for an all-solid-state battery and a preparation method thereof. A cathode slurry composition for an all-solid-state battery contains a rubber-based binder containing a polar functional group, a cathode active material, a solid electrolyte, and a complex solvent. The composite solvent contains a first solvent capable of dissolving the rubber-based binder and a second solvent capable of dispersing the cathode active material and the solid electrolyte. The first solvent has a Hansen parameter value [delta] d in the range of 19 MPa1 / 2 to 25 MPa1 / 2. A method of preparing the cathode slurry composition, a cathode for an all-solid-state battery manufactured from the cathode slurry composition, and an all-solid-state battery including the cathode are provided.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0173607 filed in the Korean Intellectual Property Office on December 4, 2023, and incorporates its entire contents herein by reference. Technical Field

[0003] The present disclosure relates to a cathode slurry composition for an all-solid-state battery using a composite solvent, a method for preparing the cathode slurry composition, a cathode for an all-solid-state battery manufactured from the cathode slurry composition, and an all-solid-state battery including the cathode. Background Art

[0004] Secondary batteries that can be charged and discharged are used as large-capacity energy storage batteries used in electric vehicles, energy storage systems, etc., or as small, high-performance energy sources for portable electronic devices such as mobile phones, cameras, and notebook computers. Compared with nickel-manganese batteries or nickel-cadmium batteries, which are advantageous in terms of convenience in use, lithium-ion batteries, which are representative secondary batteries, have advantages in terms of larger capacity per unit area size, lower self-discharge rate, and no memory effect.

[0005] However, since lithium-ion batteries use a liquid electrolyte containing an organic solvent, it is difficult to provide stability of the battery due to leakage, impact, etc. caused by the use of highly volatile organic solvents. Therefore, in order to improve the safety of lithium-ion batteries, all-solid-state batteries using solid electrolytes instead of liquid electrolytes are being actively studied.

[0006] Unlike existing lithium-ion batteries, all-solid-state batteries have the advantage of not requiring a separator because the electrolyte is solid and having a low risk of explosion due to less heat generated. However, compared with the case of using liquid electrolytes, solid electrolytes have poor chemical stability and price competitiveness, and their energy density is low, so it is still difficult to commercialize all-solid-state batteries.

[0007] To address these issues, attempts are being made to thicken the cathode. To thicken the cathode in a large-scale wet process, a high-adhesion binder that can improve the adhesion of the mixture-substrate interface is required. However, high-adhesion binders do not dissolve well in low-polarity solvents that are compatible with sulfide-based solid electrolytes, which can make electrode production difficult.

[0008] Therefore, in order to improve the energy density of all-solid-state batteries, it is necessary to develop a technology that can appropriately disperse the cathode active material and the solid electrolyte while using a solvent that can dissolve the highly adhesive binder. Summary of the invention

[0009] The present disclosure has solved the above-mentioned problems occurring in the prior art while maintaining the advantages achieved by the prior art.

[0010] One aspect of the present disclosure provides a cathode slurry composition for an all-solid-state battery and a method for preparing the same, the cathode slurry composition using a first solvent that can dissolve a rubber-based binder containing a polar functional group and a second solvent that can disperse a cathode active material and a solid electrolyte.

[0011] Another aspect of the present disclosure provides a cathode for an all-solid-state battery manufactured from the cathode slurry composition for an all-solid-state battery, and an all-solid-state battery including the cathode.

[0012] The technical problems that the present disclosure intends to solve are not limited to the above-mentioned problems, and any other technical problems not mentioned herein may be clearly understood by those skilled in the art to which the present disclosure belongs through the following description.

[0013] According to a first aspect of the present disclosure, a cathode slurry composition for an all-solid-state battery contains a rubber-based binder containing a polar functional group, a cathode active material, a solid electrolyte, and a composite solvent. The composite solvent contains a first solvent capable of dissolving the rubber-based binder and a second solvent capable of dispersing the cathode active material and the solid electrolyte. The Hansen parameter value δ of the first solvent is d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 within the range.

[0014] According to a second aspect of the present disclosure, a method for preparing a cathode slurry composition for an all-solid-state battery includes mixing a first solution obtained by mixing a rubber-based binder including a polar functional group and a first solvent with each other and a second solution obtained by mixing a cathode active material, a solid electrolyte, and a second solvent with each other.

[0015] According to a third aspect of the present disclosure, a cathode for an all-solid-state battery includes a current collector and a cathode active material layer located on the current collector. The cathode active material layer includes a cathode active material, a solid electrolyte, and a rubber-based binder containing a polar functional group. The Hansen parameter value δ of the rubber-based binder containing a polar functional group is d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 within the range.

[0016] According to a fourth aspect of the present disclosure, an all-solid-state battery includes a cathode for an all-solid-state battery, an anode, and a solid electrolyte interposed between the cathode and the anode. DETAILED DESCRIPTION

[0017] The cathode slurry composition and the preparation method thereof are described in detail hereinafter so that those skilled in the art can easily implement the cathode slurry composition.

[0018] The cathode slurry composition for an all-solid-state battery according to an embodiment of the present disclosure is a cathode slurry composition for an all-solid-state battery containing a rubber-based binder containing a polar functional group, a cathode active material, a solid electrolyte, and a composite solvent. The composite solvent may include a first solvent that can dissolve the rubber-based binder and a second solvent that can disperse the cathode active material and the solid electrolyte. The Hansen parameter value δ of the first solvent is d Can be at 19MPa 1 / 2 Up to 25MPa 1 / 2 within the range.

[0019] Sulfide-based all-solid-state batteries can use a solvent with a low polarity index to disperse the solid electrolyte. Therefore, since a rubber-based binder contained in a slurry for an all-solid-state battery together with the solid electrolyte also uses a binder with a low polarity, adhesion is low, and thus separation may occur between the mixture and the substrate.

[0020] Therefore, the present disclosure aims to improve adhesion between a mixture and a substrate by using a rubber-based adhesive including a polar functional group.

[0021] When a rubber-based binder including a polar functional group is used to improve the adhesiveness of the binder, it may be difficult to fabricate an all-solid-state battery because the rubber-based binder does not dissolve well in a solvent having a low polarity index.

[0022] Therefore, in the present disclosure, a composite solvent is used to solve the solubility problem of the high-adhesion binder, wherein the composite solvent includes a first solvent that can dissolve the rubber-based binder containing polar functional groups and a second solvent that can disperse the cathode active material and the solid electrolyte. In particular, the Hansen parameter value δ of the first solvent included in the composite solvent is d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 range, thereby being able to effectively dissolve the rubber-based adhesive having a high polarity index.

[0023] The first solvent may include a benzoate-based solvent, a carbonate-based solvent, a phthalate-based solvent, or a combination thereof.

[0024] The benzoate-based solvent includes a benzoate ester as shown in the following Chemical Formula 1, the carbonate-based solvent includes a carbonate (ethylene carbonate) structure as shown in the following Chemical Formula 2, and the phthalate-based solvent includes a phthalate ester as shown in the following Chemical Formula 3.

[0025] Chemical formula 1

[0026]

[0027] Chemical formula 2

[0028]

[0029] Chemical formula 3

[0030]

[0031] Since benzoate-based solvents, carbonate-based solvents, and phthalate-based solvents may each contain -COO- (wherein C=carbon, O=oxygen) to easily dissolve polar solutes, rubber-based adhesives containing polar functional groups may be effectively dissolved.

[0032] The benzoate solvent may include benzyl benzoate, n-propyl benzoate, isopropyl benzoate, butyl benzoate, isobutyl benzoate, sec-butyl benzoate, tert-butyl benzoate, isoamyl benzoate or a combination thereof. In one example, the benzoate solvent may include ethyl benzoate, n-propyl benzoate or a combination thereof.

[0033] The carbonate-based solvent may include ethylene carbonate, propylene carbonate, butylene carbonate, or a combination thereof. In one example, the carbonate-based solvent may include ethylene carbonate, propylene carbonate, or a combination thereof.

[0034] The phthalate solvents may include butyl benzyl phthalate, dimethyl phthalate, diisobutyl phthalate, dioctyl phthalate, diphenyl phthalate, diisopropylphenyl isophthalate, dibutoxyethyl phthalate, butyl octyl phthalate, nonyl undecyl phthalate, diisooctyl phthalate, didecyl phthalate or a combination thereof. In one example, the phthalate solvents may include butyl benzyl phthalate, diisobutyl phthalate or a combination thereof.

[0035] Since the first solvent includes a polar functional group, the first solvent may have high polarity with a polarity index ranging from 3.0 to 5.0.

[0036] The polar functional group included in the rubber-based adhesive may include a carboxyl group, a hydroxyl group, an ether group, a nitrile group, an ester group, an amino group, a salt thereof, or a combination thereof. In one example, the polar functional group may include a carboxyl group, a hydroxyl group, an ether group, a nitrile group, or a combination thereof.

[0037] The rubber-based binder can achieve high adhesion by including a polar functional group, thereby improving the interface retention between the mixture structure within the electrode and the current collector, and improving the adhesion between the mixture and the substrate.

[0038] The polar functional group may be included in an amount of 5 to 30 wt % in the rubber-based adhesive.

[0039] By including the polar functional group in a content within the above range, the adhesion of the rubber-based adhesive can be effectively improved, and at the same time, proper dispersion in the slurry for the all-solid-state battery can be achieved to prevent the resistance in the electrode from increasing. When the content of the polar functional group is too low, the adhesion of the rubber-based adhesive may decrease, and when the content of the polar functional group is too high, the resistance in the electrode may increase because the rubber-based adhesive cannot be fully dissolved in the first solvent.

[0040] The rubber-based adhesive may include butadiene rubber (BR), styrene-butadiene rubber (SBR), styrene-butadiene-styrene (SBS), nitrile rubber (NBR), ethylene-propylene diene monomer (EPDM), styrene-butadiene-acrylonitrile (SBN), styrene-isoprene-styrene (SIS), acrylic rubber (AR), or a combination thereof. In one example, the rubber-based adhesive may include butadiene rubber (BR), styrene-butadiene rubber (SBR), styrene-butadiene-styrene (SBS), nitrile rubber (NBR), or a combination thereof.

[0041] Hansen parameter values ​​δ for rubber-based adhesives containing polar functional groups d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 In the range of 50 ℃ and 100 ℃, the adhesion between the mixture and the substrate can be improved by the rubber-based adhesive containing a polar functional group.

[0042] The second solvent may include xylene, hexyl butyrate, hexane, heptane, cyclohexane, toluene, butyl butyrate, anisole, or a combination thereof. In one example, the second solvent may include xylene, hexyl butyrate, hexane, heptane, cyclohexane, or a combination thereof.

[0043] Hansen parameter value δ of the second solvent d Can be at 15MPa 1 / 2 Up to 18.5MPa 1 / 2 within a certain range to effectively disperse the cathode active material and the solid electrolyte.

[0044] In addition, the polarity index of the second solvent may be in the range of 0 to 2.5 to be compatible with the cathode active material and the solid electrolyte.

[0045] Then, a method for preparing a cathode slurry composition for an all-solid-state battery according to another embodiment of the present disclosure is described in detail.

[0046] A method of preparing a cathode slurry composition for an all-solid-state battery according to one embodiment of the present disclosure may include mixing a first solution obtained by mixing a rubber-based binder including a polar functional group and a first solvent with each other and a second solution obtained by mixing a cathode active material, a solid electrolyte, and a second solvent with each other.

[0047] In the present disclosure, a composite solvent including a first solvent that can dissolve a rubber-based binder and a second solvent that can disperse a cathode active material and a solid electrolyte is used, so that a first solution using the first solvent and a second solution using the second solvent can be prepared separately and mixed with each other.

[0048] In this regard, the second solution may be prepared by additionally mixing the second solvent with the dry mixture of the cathode active material and the solid electrolyte.

[0049] When the first solution obtained by mixing the rubber-based binder containing a polar functional group with the first solvent is first mixed with the dry mixture of the cathode active material and the solid electrolyte, not only the sulfide-based solid electrolyte may react with the first solvent to produce hydrogen sulfide, but also the dispersibility between the components in the electrode may be reduced, which may increase the electrode resistance. Therefore, in the present disclosure, the second solution can be prepared by further mixing the second solvent with the dry mixture of the cathode active material and the solid electrolyte. In addition, the second solution can be mixed with the first solution.

[0050] The content of the rubber-based adhesive in the first solution may be in the range of 5 wt % to 10 wt %.

[0051] By including the rubber-based binder in an amount within the above range, adhesion between the mixture and the substrate may be improved without deteriorating battery performance, and retention and connectivity between components in the mixture may be improved.

[0052] The first solution may be prepared by stirring the rubber-based adhesive including a polar functional group and the first solvent for 12 to 36 hours so that the rubber-based adhesive including a polar functional group is sufficiently dissolved in the first solvent.

[0053] The content of the second solvent in the second solution may be in the range of 10 wt % to 30 wt %.

[0054] By including the second solvent in an amount within the above range, the dispersibility of the solid electrolyte may be improved to prepare a uniform cathode slurry for an all-solid-state battery.

[0055] A weight ratio of the first solvent to the second solvent may be in a range of 1:0.4 to 1:1.5.

[0056] By having a weight ratio of the first solvent to the second solvent within the above range, adhesion between the mixture and the substrate may be improved, and at the same time, agglomeration of components within the electrode may be prevented to suppress an increase in electrode resistance.

[0057] The cathode for an all-solid-state battery according to one embodiment of the present disclosure may include a current collector and a cathode active material layer located on the current collector. The cathode active material layer may include a cathode active material, a solid electrolyte, and a rubber-based binder including a polar functional group. The Hansen parameter value δ of the rubber-based binder including a polar functional group is d Can be at 19MPa 1 / 2 Up to 25MPa 1 / 2 within the range.

[0058] The current collector may include nickel, copper, zinc, aluminum, or any combination thereof.

[0059] The above content can be applied to the rubber-based adhesive containing a polar functional group in the same manner.

[0060] In one example, the cathode active material layer may contain residual solvent from the cathode slurry composition for an all-solid-state battery described above. More specifically, the residual solvent includes a Hansen parameter value δ d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 The first solvent and the Hansen parameter value δ in the range d At 15MPa 1 / 2 Up to 18.5MPa 1 / 2 The above content can be applied to the first solvent and the second solvent in the same manner.

[0061] An all-solid-state battery according to one embodiment of the present disclosure may include the above-described cathode, an anode, and a solid electrolyte interposed between the cathode and the anode.

[0062] Anodes and solid electrolytes known in the art may be used.

[0063] The present disclosure is described in more detail below by examples. However, these examples are only intended to help understand the present disclosure, and the scope of the present disclosure is not limited to these examples in any way.

[0064] Example

[0065] Example 1 Preparation of cathode slurry composition for all-solid-state battery

[0066] A butadiene rubber (BR) adhesive (δ) containing 10 wt% of carboxyl groups (—COOH) (where C = carbon, O = oxygen, and H = hydrogen) was mixed. d :19.9MPa 1 / 2) and propyl benzoate (δ d :19.5MPa 1 / 2 , polarity index: 4.0) to form a mixture, and then, the mixture was stirred for 18 hours using a planetary disperser (P / D) mixer to prepare a first solution. In the first solution, the binder content was 6.5 wt %. In addition, a dry mixture obtained by dry mixing the cathode active material and the sulfide solid electrolyte using a planetary disperser (P / D) mixer was mixed with xylene (δ d : 17.6MPa 1 / 2 , polarity index: 2.5) to form a mixture, and then, the mixture was stirred for 18 hours using a planetary disperser (P / D) mixer to prepare a second solution. In the second solution, the content of xylene was 22.7 wt%.

[0067] The prepared first solution and the prepared second solution were stirred for 12 hours using a planetary disperser (P / D) mixer to prepare a cathode slurry composition for an all-solid-state battery. The weight ratio of the first solvent to the second solvent in the cathode slurry composition for an all-solid-state battery is 1:0.76.

[0068] In this regard, the Hansen parameter values ​​δ were calculated using a procedure developed by the group of Dr. C. Hansen called Hansen Solubility Parameters in Application (HSPiP) d In addition, the polarity index indicates the Snyder polarity index.

[0069] Example 2 Preparation of cathode slurry composition for all-solid-state battery

[0070] A cathode slurry composition for an all-solid-state battery was prepared in the same manner as in Example 1, except that the first solution was mixed with a dry mixture obtained by dry mixing a cathode active material with a sulfide-based solid electrolyte using a planetary disperser (P / D) mixer to form a mixture, and then xylene used as a second solvent was mixed with the mixture.

[0071] Example 3 Preparation of cathode slurry composition for all-solid-state battery

[0072] A cathode slurry composition for an all-solid-state battery was prepared in the same manner as in Example 1, except that a dry mixture obtained by dry mixing a cathode active material and a sulfide-based solid electrolyte using a planetary disperser (P / D) mixer, a first solution, and a second solvent were mixed simultaneously with each other.

[0073] Comparative Example 1 Preparation of cathode slurry composition for all-solid-state battery

[0074] A cathode slurry composition for an all-solid-state battery was prepared in the same manner as in Example 1, except that a butadiene rubber (BR) binder not including a polar functional group was used, and xylene was used as the first solvent.

[0075] Comparative Example 2 Preparation of cathode slurry composition for all-solid-state battery

[0076] A cathode slurry composition for an all-solid-state battery was prepared in the same manner as in Example 1, except that xylene was used as the first solvent, and propyl benzoate was used as the second solvent.

[0077] Comparative Example 3 Preparation of cathode slurry composition for all-solid-state battery

[0078] A cathode slurry composition for an all-solid-state battery was prepared in the same manner as in Example 1, except that a nitrile rubber (NBR) binder containing no polar functional group was used, dibromomethane was used as the first solvent, and butyl butyrate was used as the second solvent.

[0079] Experimental Example 1 Evaluation of Adhesion and Electrode Resistance

[0080] First, the prepared Examples 1-3 and Comparative Examples 1-3 were coated on a current collector using a doctor blade and then vacuum dried (V / D) at 100° C. for 4 hours to prepare an all-solid-state battery cathode sample.

[0081] The adhesion was evaluated by measuring the tensile strength of the prepared all-solid-state battery cathode specimen with respect to the horizontal direction at a speed of 30 mm / min (millimeter per minute) using a universal testing machine (UTM).

[0082] The electrode resistance of the prepared all-solid-state battery cathode sample was measured using an electrode resistance meter (measurement conditions: current: 10 mA (milliamperes), voltage range: within 0.5 V (volts)).

[0083] The results of the adhesion and resistance evaluations are shown in Table 1 below.

[0084] Table 1

[0085] Division Adhesion (gf / mm) <![CDATA[Electrode resistance (Ω·cm 2 )]]> Example 1 1.95 <![CDATA[2.25*10 -2 ]]> Example 2 1.65 <![CDATA[3.55*10 -2 ]]> Example 3 1.60 <![CDATA[3.03*10 -2 ]]> Comparative Example 1 0.28 <![CDATA[2.20*10 -2 ]]> Comparative Example 2 0.85 <![CDATA[3.23*10 -2 ]]> Comparative Example 3 0.70 <![CDATA[2.75*10 -2 ]]>

[0086] Referring to Table 1, Examples 1-3 all showed excellent adhesion at the mixture-substrate interface by using a rubber-based adhesive containing a polar functional group.

[0087] In particular, Example 1 is prepared by first mixing a dry mixture obtained by dry mixing a cathode active material and a sulfide solid electrolyte with xylene used as a second solvent to prepare a second solution and then mixing the second solution with the first solution, so that the reaction between the sulfide solid electrolyte and the first solvent is inhibited and the dispersibility between the components in the electrode is improved, resulting in low electrode resistance.

[0088] However, Comparative Examples 1 and 3 showed poor adhesion at the mixture-substrate interface due to the use of a rubber-based adhesive containing no polar functional group.

[0089] Although Comparative Example 2 uses a rubber-based adhesive containing a polar functional group, the first solvent used in Comparative Example 2 does not satisfy the Hansen parameter value δ d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 Therefore, not only the measured adhesion is low, but also the dispersion between the components within the electrode is low, resulting in high electrode resistance.

[0090] According to one embodiment of the present disclosure, the interface retention between the mixture structure within the electrode and the current collector may be improved by a high-adhesion binder.

[0091] In addition, since the cathode slurry composition for an all-solid-state battery uses a first solvent that can dissolve a rubber-based binder containing polar functional groups and a second solvent that can disperse a cathode active material and a solid electrolyte, the solubility of the binder and the dispersibility of the slurry components can be improved, thereby reducing the resistance within the electrode.

[0092] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited thereto but may be variously modified and changed by those skilled in the art to which the present disclosure pertains without departing from the spirit and scope of the present disclosure as required by the following claims.

Claims

1. A cathode slurry composition for an all-solid-state battery, the cathode slurry composition comprising: Rubber-based adhesives containing polar functional groups; cathode active material; solid electrolyte; and Composite solvents, in, The composite solvent comprises a first solvent capable of dissolving the rubber-based binder and a second solvent capable of dispersing the cathode active material and the solid electrolyte, and The Hansen parameter value δ of the first solvent d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 within the range.

2. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein The first solvent includes a benzoate solvent, a carbonate solvent, a phthalate solvent or a combination thereof.

3. The cathode slurry composition for an all-solid-state battery according to claim 2, wherein: The benzoate solvent includes benzyl benzoate, n-propyl benzoate, isopropyl benzoate, butyl benzoate, isobutyl benzoate, sec-butyl benzoate, tert-butyl benzoate, isoamyl benzoate or a combination thereof.

4. The cathode slurry composition for an all-solid-state battery according to claim 2, wherein: The carbonate solvent includes ethylene carbonate, propylene carbonate, butylene carbonate or a combination thereof.

5. The cathode slurry composition for an all-solid-state battery according to claim 2, wherein: The phthalate solvents include butyl benzyl phthalate, dimethyl phthalate, diisobutyl phthalate, dioctyl phthalate, diphenyl phthalate, diisopropylphenyl isophthalate, dibutoxyethyl phthalate, butyl octyl phthalate, nonyl undecyl phthalate, diisooctyl phthalate, didecyl phthalate or a combination thereof.

6. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein The polarity index of the first solvent is in the range of 3.0 to 5.

0.

7. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein The polar functional groups contained in the rubber-based adhesive include carboxyl groups, hydroxyl groups, ether groups, nitrile groups, ester groups, amino groups, salts thereof, or combinations thereof.

8. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein The polar functional group contained in the rubber-based adhesive may have a content in the range of 5 wt % to 30 wt %.

9. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein: The rubber adhesive includes butadiene rubber, styrene-butadiene rubber, styrene-butadiene-styrene, nitrile rubber, ethylene-propylene diene monomer, styrene-butadiene-acrylonitrile, styrene-isoprene-styrene, acrylic rubber or a combination thereof.

10. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein: Hansen parameter values ​​δ for rubber-based adhesives containing polar functional groups d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 within the range.

11. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein: The second solvent includes xylene, hexyl butyrate, hexane, heptane, cyclohexane, toluene, butyl butyrate, anisole or a combination thereof.

12. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein: The Hansen parameter value δ of the second solvent d At 15MPa 1 / 2 Up to 18.5MPa 1 / 2 within the range.

13. The cathode slurry composition for an all-solid-state battery according to claim 1, wherein: The polarity index of the second solvent is in the range of 0 to 2.

5.

14. A method for preparing a cathode slurry composition for an all-solid-state battery, the method comprising: mixing a rubber-based adhesive containing a polar functional group and a first solvent to form a first solution; mixing a cathode active material, a solid electrolyte, and a second solvent to form a second solution; as well as The first solution and the second solution are mixed to form a cathode slurry composition.

15. The method for preparing a cathode slurry composition for an all-solid-state battery according to claim 14, wherein: The second solution is prepared by additionally mixing a second solvent with the dry mixture of the cathode active material and the solid electrolyte.

16. The method for preparing a cathode slurry composition for an all-solid-state battery according to claim 14, wherein: The content of the rubber-based adhesive in the first solution is in the range of 5 wt % to 10 wt %.

17. The method for preparing a cathode slurry composition for an all-solid-state battery according to claim 14, wherein: The content of the second solvent in the second solution is in the range of 10 wt % to 30 wt %.

18. The method for preparing a cathode slurry composition for an all-solid-state battery according to claim 14, wherein: A weight ratio of the first solvent to the second solvent is in a range of 1:0.4 to 1:1.

5.

19. A cathode for an all-solid-state battery, the cathode comprising: Current collector; and a cathode active material layer disposed on the current collector, in, The cathode active material layer comprises a cathode active material, a solid electrolyte and a rubber-based binder comprising a polar functional group, and Hansen parameter values ​​δ for rubber-based adhesives containing polar functional groups d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 within the range.

20. An all-solid-state battery, comprising: cathode; an anode; and a solid electrolyte, the solid electrolyte being interposed between the cathode and the anode, in, The cathode comprises: Current collector; and a cathode active material layer disposed on the current collector, The cathode active material layer comprises a cathode active material, a solid electrolyte and a rubber-based binder containing a polar functional group, and Hansen parameter values ​​δ for rubber-based adhesives containing polar functional groups d At 19 MPa 1 / 2 Up to 25MPa 1 / 2 within the range.

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