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KR-20260063177-A - ALL-SOLID-STATE BATTERY

KR20260063177AKR 20260063177 AKR20260063177 AKR 20260063177AKR-20260063177-A

Abstract

The present invention relates to an all-solid-state battery comprising: a unit cell including a positive electrode, a solid electrolyte layer, and a negative electrode; a substrate tab protruding from the positive electrode or the negative electrode; a lead tab electrically connected to the substrate tab; a functional layer disposed between the substrate tab and the lead tab; and a pouch outer material accommodating the unit cell, wherein the functional layer comprises a polymer layer including a polymer and a metal layer including a metal having a melting point of 235°C or lower, the metal layer electrically connects the substrate tab and the lead tab to each other, and the polymer layer surrounds the outer surface of the metal layer.

Inventors

  • 김형호
  • 하재환
  • 강유진
  • 구동호
  • 김주윤

Assignees

  • 삼성에스디아이 주식회사

Dates

Publication Date
20260507
Application Date
20241030

Claims (20)

  1. A positive electrode active material for a lithium-sulfur battery comprising a composite of a sulfur-based material, a metal halide salt, and a transition metal-doped carbon-based material. A unit cell comprising an anode, a solid electrolyte layer, and a cathode; A substrate tab protruding from the anode or the cathode; A lead tab electrically connected to the above-mentioned tab; A functional layer disposed between the above-mentioned substrate tab and the above-mentioned lead tab; and It includes a pouch outer material that accommodates the above unit cell, and The above functional layer comprises a polymer layer containing a polymer and a metal layer containing a metal having a melting point of 235°C or lower, and The metal layer electrically connects the substrate tab and the lead tab to each other, and All-solid-state battery in which the polymer layer surrounds the outer surface of the metal layer.
  2. In Article 1, An all-solid-state battery, wherein the above functional layer is configured to disconnect the electrical connection between the substrate tab and the lead tab at a temperature exceeding 235°C.
  3. In Article 1, The above polymer layer is an all-solid-state battery in which the volume expands with increasing temperature.
  4. In Paragraph 3, An all-solid-state battery in which the coefficient of volume expansion of the polymer layer is 4× 10⁻⁵ /℃ to 17× 10⁻⁵ /℃.
  5. In Article 1, All-solid-state battery, wherein the above functional layer has a height change rate of 1% to 5% according to Formula 1 below: [Equation 1] Rate of change in height = {(th 2 - th 1 )/th 1 } × 100 In the above Equation 1, th 1 is the total height (㎛) of the functional layer at room temperature, and th 2 is the total height (㎛) of the functional layer when the electrical connection between the substrate tab and the lead tab is broken at a temperature of 350℃ or higher.
  6. In Article 1, An all-solid-state battery in which the thickness (t) of the polymer layer is 100 μm to 3,000 μm.
  7. In Article 1, All-solid-state battery, wherein the diameter (d) of the metal layer is 1 mm to 10 mm.
  8. In Article 1, All-solid-state battery in which the cross-sectional area of the metal layer is wider than the cross-sectional area of the polymer layer.
  9. In Article 1, An all-solid-state battery in which the cross-sectional area of the metal layer is 120% to 185% of the cross-sectional area of the polymer layer.
  10. In Article 1, A solid-state battery in which the melting point of the above metal is 200°C or lower.
  11. In Article 1, An all-solid-state battery having a thermal conductivity of 50 W/m·K or higher of the above metal.
  12. In Article 1, An all-solid-state battery having a specific resistance of 150 nΩm or less of the above metal.
  13. In Article 1, The above metal comprises tin (Sn), bismuth (Bi), indium (In), lead (Pb), cadmium (Cd), or an alloy thereof, in a solid-state battery.
  14. In Article 1, The above polymer has a higher melting point compared to the metal, in an all-solid-state battery.
  15. In Article 14, An all-solid-state battery having a melting point of 170°C or higher of the above polymer.
  16. In Article 1, The above polymer comprises a polypropylene-based (PP), polystyrene-based (PS), polybutadiene-based (PB), polyvinyl chloride-based (PVC), polyurethane-based (PU), polyamide-based (PA), epoxy-based, acrylic-based, butyl-based, phenolic-based, nylon-based, or a combination thereof, in an all-solid-state battery.
  17. In Article 1, The above-mentioned substrate tab includes a first substrate tab protruding from the anode and a second substrate tab protruding from the cathode, and An all-solid-state battery comprising a lead tab that includes a first lead tab electrically connected to the first substrate tab and a second lead tab electrically connected to the second substrate tab.
  18. In Article 17, An all-solid-state battery, wherein the functional layer is disposed between the first substrate tab and the first lead tab, and between the second substrate tab and the second lead tab.
  19. In Article 1, The above-mentioned all-solid-state battery includes a plurality of unit cells, and A solid-state battery further comprising a plurality of elastic layers interposed between each of the above plurality of unit cells.
  20. In Article 19, The above elastic layer comprises an epoxy resin, an acrylic resin, a polyimide resin, a polyester resin, a polypropylene resin, a polyamide resin, a polystyrene resin, a polyvinyl chloride resin, a polycarbonate resin, a fluoropolymer resin, a silicone rubber, or a combination thereof, in an all-solid-state battery.

Description

All-solid-state battery The present invention relates to a pouch-type all-solid-state battery. Recently, driven by industrial demands, the development of batteries with high energy density and stability is actively underway. For example, lithium-ion batteries are being commercialized not only in the fields of information and communication devices but also in the automotive sector. In the automotive sector, safety is considered particularly important because it is directly related to human life. Meanwhile, currently commercially available lithium-ion batteries use electrolytes containing flammable organic dispersion media, which can lead to fires or explosions due to overheating caused by external short circuits. To address this problem, interest in all-solid-state batteries, which replace the liquid electrolyte with a solid electrolyte, is growing. Since all-solid-state batteries do not use flammable organic dispersion media, the likelihood of fire or explosion is lower compared to lithium-ion batteries using liquid electrolytes, even if an external short circuit occurs. FIG. 1 is a cross-sectional view of a unit cell of an all-solid-state battery according to one embodiment of the present invention. FIGS. 2 and FIGS. 3 are cross-sectional views of a unit cell according to another embodiment of the present invention. FIG. 4 shows a pouch-type all-solid-state battery according to one embodiment of the present invention. Figure 5 is a cross-sectional view along the line AA' of Figure 4. Figures 6 and 7 are schematic cross-sectional views showing an enlarged view of the M area of Figure 5. FIG. 8 is a cross-sectional view of a functional layer according to one embodiment of the present invention. FIG. 9 is a cross-sectional view of a functional layer according to another embodiment of the present invention. Figure 10 is a cross-sectional view along the XX' line of Figure 9. In order to fully understand the structure and effects of the present invention, preferred embodiments of the present invention are described with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and various modifications can be made. The description of these embodiments is provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention. In this specification, when a component is described as being on another component, it means that it may be formed directly on the other component or that a third component may be interposed between them. Additionally, in the drawings, the thicknesses of the components are exaggerated for the effective description of the technical content. Throughout the specification, parts indicated by the same reference numeral represent the same components. The embodiments described herein will be explained with reference to cross-sectional and/or plan views, which are exemplary illustrations of the invention. In the drawings, the thicknesses of the films and regions are exaggerated for effective explanation of the technical content. Accordingly, the regions illustrated in the drawings are schematic in nature, and the shapes of the regions illustrated in the drawings are intended to illustrate specific forms of regions of the device and are not intended to limit the scope of the invention. In the various embodiments of this specification, terms such as first, second, third, etc., have been used to describe various components, but these components should not be limited by such terms. These terms are used merely to distinguish one component from another. The embodiments described and illustrated herein also include their complementary embodiments. All numbers and expressions indicating the amounts of components, reaction conditions, etc. described in this specification should be understood as being modified by the term "about" in all cases unless otherwise specified. The terms used herein are for describing the embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. As used herein, 'comprises' and/or 'comprising' do not exclude the presence or addition of one or more other components to the mentioned components. In this specification, "combination of these" may mean a mixture of components, a laminate, a composite, a copolymer, an alloy, a blend, and a reaction product, etc. In this specification, “metal” includes both metals and metalloids such as silicon and germanium in an elemental or ionic state, and “alloy” means a mixture of two or more metals. In this specification, “anode active material” refers to an anode material capable of undergoing lithiation and delithiation, and “anode active material” refers to an anode material capable of undergoing lithiation and delithiation. In this specification, “lith