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KR-20260065049-A - NEGATIVE ELECTRODE FOR LITHIUM METAL BATTERY AND LITHIUM METAL BATTERY INCLUDING THE SAME

KR20260065049AKR 20260065049 AKR20260065049 AKR 20260065049AKR-20260065049-A

Abstract

The present invention relates to a negative electrode for a lithium metal battery and a lithium metal battery including the same, comprising: a negative electrode current collector; and a negative electrode protective layer on the negative electrode current collector; wherein the negative electrode protective layer may comprise a polymer matrix and lithium-affinity metal particles dispersed within the polymer matrix.

Inventors

  • 이강희
  • 곽병도
  • 배우진
  • 문종석
  • 김희민
  • 우현식
  • 박종석
  • 신주훈
  • 홍동기
  • 표수진

Assignees

  • 삼성에스디아이 주식회사

Dates

Publication Date
20260508
Application Date
20241031

Claims (20)

  1. cathode current collector; and It includes a cathode protective layer on the above-mentioned cathode current collector; The above-described negative electrode protective layer comprises a polymer matrix and lithium-affinity metal particles dispersed within the polymer matrix, for a negative electrode for a lithium metal battery.
  2. In paragraph 1, The lithium-affinity metal particles described above comprise aluminum (Al), silver (Ag), copper (Cu), gold (Au), titanium (Ti), nickel (Ni), cobalt (Co), iron (Fe), manganese (Mn), magnesium (Mg), potassium (K), chromium (Cr), tin (Sn), vernadium (V), zinc (Zn), or a combination thereof, for a negative electrode for a lithium metal battery.
  3. In paragraph 1, The above lithium-affinity metal particles comprise silver (Ag), nickel (Ni), cobalt (Co), iron (Fe), zinc (Zn), or a combination thereof, for a negative electrode for a lithium metal battery.
  4. In paragraph 1, A negative electrode for a lithium metal battery, wherein the average particle size of the lithium-affinity metal particles is 5 nm to 900 nm.
  5. In paragraph 1, A negative electrode for a lithium metal battery, wherein the negative electrode protective layer comprises 10 to 40 parts by weight of the lithium-affinity metal particles per 100 parts by weight of the polymer matrix.
  6. In paragraph 1, The above polymer matrix is carboxymethylcellulose (CMC), polyethylene glycol (PEG), polyethylene oxide (PEO), polyethylene glycol methacrylate (PEGMA), polyethylene glycol dimethacrylate (PEGDMA), polyethylene carbonate (PEC), polytrimethylene carbonate (PTMC), polypropylene carbonate (PPC), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP), polyacrylonitrile (PAN), A negative electrode for a lithium metal battery comprising polyacrylic acid (PAA) or a combination thereof.
  7. In paragraph 1, The above polymer matrix comprises poly(ethylene oxide, PEO), poly(vinylidene fluoride, PVDF), poly(vinylidene fluoride-co-hexafluoropropylene, PVDF-HFP), polyacrylonitrile (PAN), polyacrylic acid (PAA), or a combination thereof, for a negative electrode for a lithium metal battery.
  8. In paragraph 1, A negative electrode for a lithium metal battery, wherein the thickness of the negative electrode protective layer is 0.1 to 30 μm.
  9. In paragraph 1, The above cathode protective layer further includes a binder, The above binder is polytetrafluoroethylene (PTFE), polyamide-imide (PAI), polyimide (PI), styrene-butadiene rubber (SBR), (meth)acrylated styrene-butadiene rubber, polyethylene oxide (PEO), polyphosphazene, poly(meth)acrylonitrile (PAN), (meth)acrylic resin, phenol resin, epoxy resin, polyvinyl alcohol (PVA), polyvinylidene fluoride (PVDF), and polyvinylidene A negative electrode for a lithium metal battery comprising a polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP) or a combination thereof.
  10. In paragraph 1, The above-mentioned cathode current collector further includes a carbon layer disposed on one or both sides, and The above carbon layer comprises amorphous carbon, crystalline carbon, or a combination thereof, for a negative electrode of a lithium metal battery.
  11. In Paragraph 10, A negative electrode for a lithium metal battery, wherein the thickness of the carbon layer is 1 μm to 5 μm.
  12. In paragraph 1, The above-described negative electrode protective layer extends to at least one side of the above-described negative electrode current collector, for a negative electrode of a lithium metal battery.
  13. In paragraph 1, It further includes a lithium metal layer disposed between the above-mentioned negative current collector and the above-mentioned negative protection layer, and The above lithium metal layer comprises lithium or a lithium alloy, a negative electrode for a lithium metal battery.
  14. In Paragraph 13, The above lithium alloy comprises a Li-Al alloy, a Li-Sn alloy, a Li-In alloy, a Li-Ag alloy, a Li-Au alloy, a Li-Zn alloy, a Li-Ge alloy, a Li-Si alloy, or a combination thereof, for a negative electrode for a lithium metal battery.
  15. A positive layer comprising a positive current collector and a positive active material layer on the positive current collector; cathode layer; and It includes an electrolyte layer disposed between the anode layer and the cathode layer; A lithium metal battery comprising the negative electrode of claim 1, wherein the above negative electrode layer comprises the negative electrode.
  16. In paragraph 15, A lithium metal battery in which the region between the negative current collector and the negative protection layer is a Li-free region that does not contain lithium (Li).
  17. In paragraph 15, It further includes a lithium metal layer disposed between the above-mentioned negative electrode current collector and the above-mentioned negative electrode protective layer, and The above lithium metal layer comprises lithium or a lithium alloy, and A lithium metal battery comprising the above lithium alloy, a Li-Al alloy, a Li-Sn alloy, a Li-In alloy, a Li-Ag alloy, a Li-Au alloy, a Li-Zn alloy, a Li-Ge alloy, a Li-Si alloy, or a combination thereof.
  18. In paragraph 15, A lithium metal battery comprising a positive electrode active material layer comprising lithium transition metal oxides such as lithium cobalt oxide (LCO), lithium nickel oxide, lithium nickel cobalt oxide, lithium nickel cobalt aluminum oxide (NCA), lithium nickel cobalt manganese oxide (NCM), lithium manganate, and lithium iron phosphate, nickel sulfide, copper sulfide, lithium sulfide, iron oxide, or vanadium oxide, or a combination thereof.
  19. In paragraph 15, The above electrolyte layer comprises a liquid electrolyte, a solid electrolyte, or a combination thereof in a lithium metal battery.
  20. In paragraph 15, The above electrolyte layer includes a solid electrolyte, and The above solid electrolyte includes a sulfide-based solid electrolyte, and The above sulfide-based solid electrolyte is Li₃PO₄ - Li₂SO₄ , Li₂SP₂S₅ , Li₂SP₂S₅ - LiX , where X is a halogen element, Li₂SP₂S₅- Li₂O , Li₂SP₂S₅-Li₂O - LiI , Li₂S-SiS₂, Li₂S - SiS₂ - LiI , Li₂S -SiS₂ - LiBr , Li₂S - SiS₂ - LiCl , Li₂S - SiS₂ - B₂S₃ -LiI , Li₂S -SiS₂- P₂S₅ - LiI , Li₂SB₂S₃ , Li₂SP₂S₅ - Z₀S₀ , mS₀N₅ , where m and n are positive numbers, Z is one of Ge, Zn , or Ga, Li₂S - GeS₂ , Li₂S - SiS₂ -Li A lithium metal battery comprising 3 PO 4 , Li 2 S-SiS 2 -Li p MO q , where p and q are positive numbers, M is one of P, Si, Ge, B, Al, Ga In, 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.

Description

Negative electrode for lithium metal battery and lithium metal battery including the same The invention relates to a negative electrode for a lithium metal battery and a lithium metal battery including the same. Currently commercially available lithium secondary batteries mainly use carbon-based negative electrode active materials such as graphite. Carbon-based negative electrode active materials do not change in volume during charging and discharging, so the stability of lithium secondary batteries is high. The theoretical electric capacity of graphite is small, about 372 mAh/g. Lithium metal can be used as a negative electrode active material. The theoretical electric capacity of lithium metal is approximately 3,860 mAh/g, which is larger than that of graphite. During charging and discharging, dendrites may form on the surface of lithium metal due to side reactions with the electrolyte, and the growth of these dendrites can cause a short circuit between the positive and negative electrodes. Consequently, the lifespan characteristics of lithium metal batteries containing lithium metal may be degraded. A method is required to improve the lifespan characteristics of lithium metal batteries containing lithium metal. FIG. 1 is a cross-sectional view of a lithium metal battery according to an exemplary embodiment. Figure 2 is a conceptual diagram illustrating the stacking of lithium metal on a current collector at the negative electrode of a lithium metal battery. Figure 3 is a conceptual diagram illustrating the stacking of lithium metal on a current collector at the negative electrode of a lithium metal battery including a protective layer. FIG. 4 is a cross-sectional view of a negative electrode for a lithium metal battery according to an exemplary embodiment. FIG. 5 is a conceptual diagram illustrating the stacking of lithium metal on a current collector in a negative electrode for a lithium metal battery according to an exemplary embodiment. FIG. 6 is a cross-sectional view of a negative electrode for a lithium metal battery according to another exemplary embodiment. FIG. 7 is a cross-sectional view of a negative electrode for a lithium metal battery according to another exemplary embodiment. FIG. 8 is a cross-sectional view of a negative electrode for a lithium metal battery according to another exemplary embodiment. FIG. 9 is a cross-sectional view of a lithium metal battery according to another exemplary embodiment. FIG. 10 is a graph showing the capacity retention rate of lithium metal batteries according to Example 1, Comparative Example 1, and Comparative Example 2. The present inventive concept described below is subject to various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present inventive concept to specific embodiments and should be understood to include all modifications, equivalents, or substitutions that fall within the scope of the description of the present inventive concept. The terms used below are used merely to describe specific embodiments and are not intended to limit the creative concept. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the following, terms such as “comprising” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, components, materials, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, components, materials, or combinations thereof. As used below, “ ” may be interpreted as “and” or “or” depending on the context. In the drawings, thicknesses have been enlarged or reduced to clearly represent various layers and regions. Throughout the specification, the same reference numerals have been used for similar parts. Throughout the specification, when a part such as a layer, film, region, or plate is described as being “on” or “above” another part, this includes not only cases where it is directly above another part but also cases where there is another part in between. Throughout the specification, terms such as “first,” “second,” etc., may be used to describe various components, but the components should not be limited by these terms. In this specification and drawings, components having substantially the same functional configuration are referred to by the same reference numerals to avoid redundant descriptions. In the present disclosure, the “size” of a particle is, for example, the “particle diameter” of the particle. The “particle diameter” of the particle represents the average diameter when the particle is spherical and represents the average major axis length when the particle is non-spherical. The particle diameter of the particle can be measured using a particle size analyzer (PSA). T