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KR-20260064525-A - All-solid-state battery and manufacturing method thereof

KR20260064525AKR 20260064525 AKR20260064525 AKR 20260064525AKR-20260064525-A

Abstract

The present invention relates to an all-solid-state battery using lithium or a lithium alloy as a negative electrode active material, comprising a positive electrode, a solid electrolyte layer, a non-negative electrode coating layer, and a negative electrode current collector, wherein the ratio of the thickness of the solid electrolyte layer to the planar area of the negative electrode current collector is greater than 0.125 μm/ cm² and less than 1.25 μm/ cm² , and to a method for manufacturing the same. According to the present invention, it is possible to provide an all-solid-state battery and a method for manufacturing the same that have excellent energy density characteristics, as well as output performance and cycle performance, without short circuits during cycling.

Inventors

  • 김제덕
  • 이지은
  • 김영복
  • 김지영

Assignees

  • 주식회사 엘지에너지솔루션

Dates

Publication Date
20260507
Application Date
20251014
Priority Date
20241031

Claims (16)

  1. As an all-solid-state battery using lithium or a lithium alloy as the negative electrode active material, It includes an anode, a solid electrolyte layer, a non-cathode coating layer, and a cathode current collector, An all-solid-state battery characterized in that the ratio of the thickness of the solid electrolyte layer to the planar area of the above-mentioned negative electrode current collector is greater than 0.125 μm/ cm² and less than 1.25 μm/ cm² .
  2. In Article 1, An all-solid-state battery characterized in that the ratio of the thickness of the solid electrolyte layer to the thickness of the above-mentioned non-cathode coating layer is greater than 0.5 and less than 5.
  3. In Article 1, An all-solid-state battery characterized by the thickness of the solid electrolyte layer being 5 to 100 μm.
  4. In Article 1, All-solid-state battery characterized in that the above-mentioned non-cathode coating layer comprises amorphous carbon.
  5. An all-solid-state battery according to claim 4, characterized in that the amorphous carbon is one or more selected from the group consisting of carbon black, acetylene black, furnace black, Ketjen black, and graphene.
  6. An all-solid-state battery according to claim 1, characterized in that the non-cathode coating layer further comprises a lithium-affinity element that forms an alloy or compound with lithium.
  7. A solid-state battery according to claim 6, characterized in that the lithium-affinity element is one or more selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn).
  8. An all-solid-state battery according to claim 6, characterized in that the non-cathode coating layer contains a lithium-affinity element in a range of 10 to 50 parts by weight per 100 parts by weight of amorphous carbon.
  9. A solid-state battery according to claim 1, characterized in that the non-cathode coating layer further comprises a binder.
  10. An all-solid-state battery according to claim 9, wherein the non-cathode coating layer comprises a binder in a range of 1 to 20 parts by weight per 100 parts by weight of amorphous carbon.
  11. An all-solid-state battery according to claim 1, characterized in that the solid electrolyte layer comprises a sulfide-based solid electrolyte.
  12. In claim 11, the sulfide-based solid electrolyte is Li₂SP₂S₅ - Li₂O , Li₂SP₂S₅- Li₂O - LiI , Li₂S-SiS₂, Li₂S - SiS₂ - LiI , Li₂S- SiS₂ - LiBr , Li₂S - SiS₂ - LiCl, Li₂S -SiS₂- B₂S₃ -LiI, Li₂S -SiS₂- Li₃PO₄ , Li₂S -SiS₂- Li p MO q ( p and q are positive numbers, M is one of P , Si, Ge, B , Al, Ga , and In ) , Li₂S - SiS₂ - P₂S₅ - LiI , Li₂SP₂S₅ , Li₂SP₂S₅ - LiX ( X is a halogen element), Li₂SB₂S₃ , Li₂SP₂ An all-solid-state battery characterized by S 5 -Z m S n (m, n are positive numbers), Z being one of Ge, Zn or Ga, Li 2 S-GeS 2 ,Li 7-x PS 6 -x Cl x (0≤x≤2), Li 7 -x PS 6-x Br x (0≤x≤2), and Li 7-x PS 6-x I x (0≤x≤2).
  13. An all-solid-state battery according to claim 1, characterized in that the ratio of the 1C discharge capacity to the 0.1C discharge capacity is 90% or more.
  14. An all-solid-state battery according to claim 1, characterized by having an energy density per unit volume of 700 Wh/L or more.
  15. A method for manufacturing an all-solid-state battery using lithium or a lithium alloy as a negative electrode active material, A step of forming a non-cathode coating layer on a cathode current collector; A step of forming a solid electrolyte layer on the above-mentioned non-cathode coating layer; Step of stacking an anode on the solid electrolyte layer; and It includes the step of performing a hydrostatic press process, A method for manufacturing an all-solid-state battery, characterized in that the ratio of the thickness of the solid electrolyte layer to the planar area of the above-mentioned negative electrode current collector is greater than 0.125 μm/ cm² and less than 1.25 μm/ cm² .
  16. In Article 15, A method for manufacturing an all-solid-state battery, characterized in that the step of forming a solid electrolyte layer on the above-mentioned non-cathode coating layer comprises: a step of applying a solid electrolyte slurry on the non-cathode coating layer; and a step of drying the applied solid electrolyte slurry.

Description

All-solid-state battery and manufacturing method thereof The present invention relates to an all-solid-state battery using lithium or a lithium alloy as a negative electrode active material and a method for manufacturing the same. The present application claims the benefit of priority based on Korean Patent Application No. 2024-0152485 filed on October 31, 2024, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of the specification. Recently, there has been growing interest in anodeless solid-state batteries, which allow a lithium metal layer to be formed during the charging process without forming a separate negative active material layer on the negative current collector during the battery manufacturing process. Anodeless solid-state batteries are useful for electric vehicles as they offer excellent stability and high energy density, which can increase the driving range on a single charge. However, even for anodeless solid-state batteries, further improving energy density remains a challenge, and there is also a need to further enhance output performance and cycle performance. The drawings in this specification are merely for the purpose of facilitating an understanding of the invention, and the scope of the invention should not be interpreted as being limited to the embodiments described in the drawings in this specification. Figure 1 is a graph showing the output performance evaluation results according to Evaluation Example 1. Figure 2 is a graph showing the cycle performance evaluation results according to Evaluation Example 1. FIG. 3 is a flowchart illustrating a method for manufacturing an all-solid-state battery according to one embodiment of the present invention. Figure 4 is an image showing an example of a cell jig. Terms and words used in this specification and claims shall not be interpreted as being limited to their ordinary or dictionary meanings, but shall be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Therefore, it should be understood that the configuration of the embodiments described in this specification is merely one of the most preferred embodiments of the present invention and does not represent all of the technical ideas of the present invention, and that various equivalents and modifications that can replace them may exist at the time of filing this application. In this specification, singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, when a part is described as “comprising” a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Thus, for example, a composition comprising compound A may include compounds other than A. However, the term “comprising” also encompasses, in a more restrictive sense as a specific embodiment thereof, “essentially/essentially composed of” and “composed of,” so, for example, a “composition comprising compound A” may also be (essentially/essentially) composed of compound A. In connection with this, terms such as “comprising” or “having,” as described in this specification, are intended to specify the existence of the implemented features, numbers, steps, components, or combinations thereof, and should not be understood as precluding the existence or addition of one or more other features, numbers, steps, components, or combinations thereof. In this specification, when any layer is described as being located “on” or “between” another arbitrary layer, this includes not only cases where any layer is in contact with another arbitrary layer, but also cases where another layer or material, etc., exists between the two layers. Where in this specification a quantity, concentration, or other value or parameter is given as an enumeration of a range, a preferred range, a preferred upper limit, and a preferred lower limit, it should be understood that any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether the range is disclosed separately, specifically discloses all ranges that may be formed. Where a range of numerical values is mentioned in this specification, unless otherwise stated, for example, without limiting terms such as greater than or less than, the range is intended to include its endpoint value and all integers and fractions within that range. The scope of the invention is not intended to be limited to the specific value mentioned when defining the range. In the present specification, where “about” is written before a specific numerical value or the upper and lower limits of a specific numerical range, unless specifically otherwise stipulated, it means that the numerical value or the upper and lower limit