All-solid-state battery and method of manufacturing same

Abstract

An all-solid-state battery and a method of manufacturing the same are disclosed. The all-solid-state battery includes a positive electrode layer, a negative electrode layer, and a solid electrolyte layer between the positive electrode layer and the negative electrode layer. At least one of the positive electrode layer and the solid electrolyte layer includes a lubricating additive. The lubricant additive includes one of a first compound including a repeating unit, a second compound including a repeating unit, and a combination of the first compound and the second compound.

Description

[0001] This application claims priority to Korean Patent Application No. 10-2024-0112241, filed on August 21, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] This disclosure relates to all-solid-state batteries and methods for manufacturing all-solid-state batteries, and more specifically, to all-solid-state batteries manufactured by adding lubricating additives and a low-pressure rolling process, and methods for manufacturing all-solid-state batteries. Background Technology

[0003] The development of high-energy-density and safe batteries is driven by industrial demand. For example, lithium-ion batteries are being commercialized not only in information-related and communication devices, but also in industries such as the automotive industry. In the automotive industry, safety is given particular emphasis due to its direct relationship with protecting human life.

[0004] All-solid-state batteries exist that replace the electrolyte solution with a solid electrolyte. Because all-solid-state batteries do not use flammable organic dispersion media, the likelihood of fire or explosion is significantly reduced, even in the event of a short circuit. Therefore, all-solid-state batteries can offer significantly increased safety compared to lithium-ion batteries that use electrolyte solutions. Summary of the Invention

[0005] Some example embodiments of this disclosure include lubricating additives for increasing the formability and elongation of electrode plates.

[0006] Some exemplary embodiments of this disclosure include a method for manufacturing all-solid-state batteries that can be manufactured by low-pressure rolling.

[0007] According to some example embodiments of this disclosure, an all-solid-state battery may include a positive electrode layer, a negative electrode layer, and a solid electrolyte layer between the positive electrode layer and the negative electrode layer. At least one of the positive electrode layer and the solid electrolyte layer may include a lubricating additive. The lubricating additive may include one of the following: a first compound comprising repeating units represented by Chemical Formula 1; a second compound comprising repeating units represented by Chemical Formula 2; and a combination of the first compound and the second compound.

[0008] Chemical Formula 1:

[0009] In chemical formula 1, n can be an integer in the range of 1 to 100, and R1 can be or include hydroxyl, methyl, amino, acryloyl, phenyl, acrylonitrile, amide, alkyl, or carboxyl groups.

[0010] Chemical formula 2:

[0011] In chemical formula 2, m can be an integer in the range between 1 and 100.

[0012] According to some exemplary embodiments of this disclosure, an all-solid-state battery may include a positive electrode layer, a negative electrode layer, and a solid electrolyte layer between the positive electrode layer and the negative electrode layer. At least one of the positive electrode layer and the solid electrolyte layer may include a lubricating additive. The molecular weight of the lubricating additive may be in the range of about 200 g / mol to about 2,000 g / mol; and the coefficient of friction may be in the range of about 0.01 to about 0.1.

[0013] According to some example embodiments of this disclosure, a method for manufacturing an all-solid-state battery may include the following steps: mixing a positive electrode active material, a binder, and a lubricating additive with each other to prepare a positive electrode slurry; coating the positive electrode slurry onto a positive electrode current collector to form a positive electrode active material layer; and stacking (e.g., sequentially stacking) a solid electrolyte layer and a negative electrode layer on the positive electrode active material layer. The lubricating additive may include one of the following: a first compound comprising repeating units represented by Chemical Formula 1; a second compound comprising repeating units represented by Chemical Formula 2; and a combination of the first compound and the second compound.

[0014] Chemical Formula 1:

[0015] In chemical formula 1, n can be an integer in the range of 1 to 100, and R1 can be or include hydroxyl, methyl, amino, acryloyl, phenyl, acrylonitrile, amide, alkyl, or carboxyl groups.

[0016] Chemical formula 2:

[0017] In chemical formula 2, m can be an integer in the range between 1 and 100. Attached Figure Description

[0018] Figure 1 A cross-sectional view of an all-solid-state battery according to some example embodiments of the present disclosure is shown.

[0019] Figure 2 A plan view illustrating an all-solid-state battery according to some example embodiments of the present disclosure is shown.

[0020] Figure 3 A cross-sectional view of an all-solid-state battery according to some example embodiments of the present disclosure is shown.

[0021] Figure 4A cross-sectional view of the positive electrode layer of an all-solid-state battery according to some example embodiments of the present disclosure is shown.

[0022] Figure 5 It shows Figure 4 The portion M1 depicted is an enlarged view before pressing the positive electrode layer according to some example embodiments of this disclosure.

[0023] Figure 6 It shows Figure 4 The portion M1 depicted is an enlarged view after pressing the positive electrode layer according to some example embodiments of the present disclosure.

[0024] Figure 7 A cross-sectional view illustrating a negative electrode layer according to some example embodiments of the present disclosure is shown.

[0025] Figure 8 A conceptual diagram illustrating the pressing steps for manufacturing an all-solid-state battery according to some example embodiments of the present disclosure is shown.

[0026] Figure 9 A flowchart illustrating a method for manufacturing an all-solid-state battery according to some example embodiments of the present disclosure is shown.

[0027] Figure 10 A graph is shown illustrating the compression characteristics of an all-solid-state battery according to some example embodiments of the present disclosure. Detailed Implementation

[0028] To fully understand the structure and effects of this disclosure, some exemplary embodiments of the disclosure have been described with reference to the accompanying drawings. However, it should be noted that this disclosure is not limited to the following exemplary embodiments and can be implemented in various forms. Rather, the exemplary embodiments are provided merely to disclose the disclosure and to enable those skilled in the art to fully understand its scope.

[0029] In this specification, it is understood that when an element is referred to as being "on" another element, the element may be "directly on" the other element, or an intervening element may be present therein. In the accompanying drawings, the thickness of some components is exaggerated for the purpose of effectively explaining the technical content. Throughout the specification, the same reference numerals denote the same elements.

[0030] Unless otherwise specifically stated in this specification, singular expressions may include plural expressions. Furthermore, unless otherwise specifically stated, the phrase "A or B" may mean "A but not B," "B but not A," and "A and B." The terms "including / comprise" and / or variations thereof as used in this specification do not exclude the presence or addition of one or more other components.

[0031] In this specification, the term "combination thereof" may refer to mixtures, stacks, complexes, copolymers, alloys, blends, or reaction products.

[0032] When the terms “about” or “substantially” are used in conjunction with numerical values ​​in this specification, it means that the relevant numerical value includes a tolerance of ±10% around the stated value. When a range is specified, the range includes all values ​​in increments such as 0.1%.

[0033] Figure 1 A cross-sectional view illustrating an all-solid-state battery according to some example embodiments of the present disclosure is shown. (Refer to...) Figure 1 This illustration shows a single-cell microcell (MNC) of an all-solid-state battery according to an example embodiment of the present disclosure. The single-cell MNC may include a positive electrode layer 100, a negative electrode layer 200 opposite to the positive electrode layer 100, and a solid electrolyte layer 300 between the positive electrode layer 100 and the negative electrode layer 200. However, the present disclosure is not limited thereto, and the single-cell MNC may also include additional functional layers (not shown), such as adhesion enhancement layers, between the positive electrode layer 100 and the solid electrolyte layer 300 or between the negative electrode layer 200 and the solid electrolyte layer 300.

[0034] The positive electrode layer 100 may include a positive electrode current collector 110 and a positive electrode active material layer 120 on the positive electrode current collector 110. The positive electrode active material layer 120 may include at least one of a positive electrode active material, a solid electrolyte, a conductive material, and a binder.

[0035] The positive electrode current collector 110 can provide a reference surface on which the positive electrode active material layer 120 is formed. The positive electrode current collector 110 can have a plate or foil shape. For example, the positive electrode current collector 110 can include at least one of indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), and alloys thereof.

[0036] In the exemplary embodiments of this disclosure, the positive electrode current collector 110 may be omitted. Although not shown, in order to increase the adhesion between the positive electrode current collector 110 and the positive electrode active material layer 120, a carbon layer with a thickness in the range of about 0.1 μm to about 4 μm may be further provided between the positive electrode current collector 110 and the positive electrode active material layer 120.

[0037] The positive electrode active material may include materials capable of reversibly adsorbing and desorbing lithium ions. For example, the positive electrode active material may include at least one of lithium transition metal oxides (e.g., lithium cobalt oxide (LCO), lithium nickel oxide, lithium nickel cobalt oxide, lithium nickel cobalt aluminum oxide (NCA), lithium nickel cobalt manganese oxide (NCM), lithium manganese oxide, or lithium iron phosphate), nickel sulfide, copper sulfide, lithium sulfide, iron oxide, and vanadium oxide, but this disclosure is not limited thereto. The positive electrode active material may be included alone or as a mixture of two or more substances.

[0038] Lithium transition metal oxides can be, for example, made of Li a A 1-b B b D2 (where 0.90≤a≤1 and 0≤b≤0.5), Li a E 1-b B b O 2-c D c (Where, 0.90≤a≤1, 0≤b≤0.5 and 0≤c≤0.05), LiE 2-b B b O 4-c D c (where 0 ≤ b ≤ 0.5 and 0 ≤ c ≤ 0.05), Li a Ni 1-b-c Co b B c D α (Where, 0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05 and 0<α<2), Li a Ni 1-b-c Co b B c O 2-α F α (Where, 0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05 and 0<α<2), Li a Ni 1-b-c Mn b B c D α (Where, 0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05 and 0<α≤2), Li a Ni 1-b-c Mn b B c O 2-α F α (Where, 0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05 and 0<α<2), Li a Ni b E c G dO2 (where 0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5 and 0.001≤d≤0.1), Li a Ni b Co c Mn d G e O2 (where 0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5 and 0.001≤e≤0.1), Li a NiG b O2 (where 0.9≤a≤1 and 0.001≤b≤0.1), Li a CoG b O2 (where 0.90≤a≤1 and 0.001≤b≤0.1), Li a MnG b O2 (where 0.90≤a≤1 and 0.001≤b≤0.1), Li a Mn2G b O4 (where 0.90≤a≤1 and 0.001≤b≤0.1), QO2, QS2, LiQS2, V2O5, LiV2O5, LiIO2, LiNiVO4, Li 3-f J2(PO4)3 (where 0≤f≤2), Li 3-f A compound represented by one of Fe2(PO4)3 (where 0≤f≤2) and LiFePO4. In the above compounds, "A" may be or include at least one of Ni, Co, Mn and combinations thereof; "B" may be or include at least one of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements and combinations thereof; "D" may be or include at least one of O, F, S, P and combinations thereof; "E" may be or include at least one of Co, Mn and combinations thereof; "F" may be or include at least one of F, S, P and combinations thereof; "G" may be or include at least one of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V and combinations thereof; "Q" may be or include at least one of Ti, Mo, Mn and combinations thereof; "I" may be or include at least one of Cr, V, Fe, Sc, Y and combinations thereof; and "J" may be or include at least one of V, Cr, Mn, Co, Ni, Cu and combinations thereof.

[0039] The positive electrode active material may include, for example, a lithium salt of a transition metal oxide having a layered rock salt-type structure among the lithium transition metal oxides discussed above. The term "layered rock salt-type structure" may refer to a structure in which oxygen atom layers and metal atom layers are alternately and regularly arranged in the <111> direction of the cubic rock salt-type structure, where each atom layer forms a two-dimensional plane. The term "cubic rock salt-type structure" may refer to the sodium chloride (NaCl)-type structure as a type of crystal structure, and for example, has a structure in which face-centered cubic (FCC) lattices each formed by cations and anions are offset by 1 / 2 of the ridge of the unit lattice from each other. The lithium transition metal oxide having a layered rock salt-type structure may be or include a ternary lithium transition metal oxide, such as LiNi x Co y Al z O2 (NCA) or LiNi x Co y Mn z O2 (NCM) (where 0 < x < 1, 0 < y < 1, 0 < z < 1, and x + y + z = 1). When the positive electrode active material includes a ternary lithium transition metal oxide having a layered rock salt-type structure, the single cell MNC may have an increased energy density and improved thermal stability.

[0040] The compound included in the positive electrode active material may be covered with a coating (not shown). The positive electrode active material may be included in a mixture of the compound and the compound with the coating added. The coating added to the surface of the positive electrode active material may include, for example, at least one of oxides, hydroxides, hydroxyoxides, carbonate oxy salts, and bicarbonate salts of the coating elements discussed below. The compound forming the coating may be amorphous or crystalline. The coating elements included in the coating may include at least one of Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or a mixture thereof. The coating may include, for example, Li2O-ZrO2 (LZO). The method for forming the coating may be any method that does not negatively affect the physical properties of the positive electrode active material. The method for forming the coating may include, for example, spraying or dipping.

[0041] When the positive electrode active material includes nickel (Ni) as a ternary lithium transition metal oxide (such as NCA or NCM), the capacity density of the single cell MNC may be increased to reduce the elution of metal from the positive electrode active material in the charged state. Therefore, the single cell MNC may improve the cycle characteristics in the charged state. The term "cycle characteristics" may refer to the property indicating the degree of deterioration of the single cell MNC due to charging and discharging. For example, a single cell MNC having high cycle characteristics may deteriorate less due to charging and discharging, while a single cell MNC having low cycle characteristics may deteriorate more due to charging and discharging.

[0042] The positive electrode active material can have, for example, a generally spherical or generally elliptical particle shape. There are no limitations on the particle size and amount of the positive electrode active material. The following discussion... Figure 5 and Figure 6 The irregularly shaped positive electrode active material AM is shown.

[0043] Solid electrolytes can include sulfide solid electrolytes with desired or improved lithium-ion conductivity. Sulfide solid electrolytes can include, for example, Li₂S-P₂S₅, Li₂S-P₂S₅-LiX (where X is a halogen element), Li₂S-P₂S₅-Li₂O, Li₂S-P₂S₅-Li₂O-LiI, Li₂S-SiS₂, Li₂S-SiS₂-LiI, Li₂S-SiS₂-LiBr, Li₂S-SiS₂-LiCl, Li₂S-SiS₂-B₂S₃-LiI, Li₂S-SiS₂-P₂S₅-LiI, Li₂S-B₂S₃, and Li₂S-P₂S₅-Z. m S n (Where m and n are each positive integers, and "Z" is or includes at least one of Ge, Zn, and Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li p MO q (Where p and q are each positive integers, and "M" is or includes at least one of P, Si, Ge, B, Al, Ga, and In), Li 7-x PS 6-x Cl x (where 0≤x≤2), Li 7-x PS 6-x Br x (where 0 ≤ x ≤ 2) and Li 7-x PS 6-x I x At least one of the following (where 0 ≤ x ≤ 2).

[0044] Sulfide solid electrolytes may be or include argentite-germanium sulfide compounds, such as Li 7-x PS 6-x Cl x (where 0≤x≤2), Li 7-x PS 6-x Br x (where 0 ≤ x ≤ 2) and Li 7-x PS 6-x I x(where 0 ≤ x ≤ 2) at least one of the following. For example, sulfide solid electrolytes may be or include argentite-germanium sulfide compounds, which include at least one of Li6PS5Cl, Li6PS5Br and Li6PS5I.

[0045] Optionally, the sulfide solid electrolyte may be or include a sulforaphane-germanium ore type compound, which includes Li 7-a M a PS 6-c X c (Where 0 ≤ a ≤ 2 and 0 ≤ c ≤ 2). In the above chemical formula, X can be or include at least one of F, Br, Cl, or combinations thereof. Additionally, M can be or include at least one of scandium (Sc), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), zinc (Zn), cadmium (Cd), mercury (Hg), aluminum (Al), gallium (Ga), indium (In), thallium (Tl), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), arsenic (As), antimony (Sb), bismuth (Bi), or combinations thereof.

[0046] The sulfide-germanium ore type solid electrolyte can have a density in the range of about 1.5 g / cc to about 2.0 g / cc. Because the sulfide-germanium ore type solid electrolyte has a density equal to or greater than about 1.5 g / cc, the internal resistance of the all-solid-state battery can be reduced, and short circuits in the solid electrolyte layer and penetration caused by lithium dendrite formation can be hindered or prevented. The solid electrolyte can have an elastic modulus, for example, in the range of about 15 GPa to about 35 GPa.

[0047] The medium average particle size (D) of the solid electrolyte included in the positive electrode active material layer 120 50 The particle size can be smaller than the average particle size of the solid electrolyte included in the solid electrolyte layer 300. For example, the average particle size (D) of the solid electrolyte in the positive electrode active material layer 120 is moderate. 50 ) can be the medium-sized average particle size (D) of the solid electrolyte included in the solid electrolyte layer 300. 50 The average particle size (D) is approximately equal to or less than approximately 90%, equal to or less than approximately 80%, equal to or less than approximately 70%, equal to or less than approximately 60%, equal to or less than approximately 50%, equal to or less than approximately 40%, equal to or less than approximately 30%, or equal to or less than approximately 20%. 50The median diameter can be measured using a laser particle size distribution analyzer.

[0048] The positive electrode active material layer 120 may include a conductive material. The conductive material can be conductive without causing chemical changes in the single-cell MNC and can increase the conductivity of both the positive electrode active material and the solid electrolyte. The conductive material may include carbon-based materials. The conductive material may include one or more of, for example, graphite, carbon black, acetylene black, carbon nanofibers, and carbon nanotubes.

[0049] The positive electrode active material layer 120 may further include an adhesive. The adhesive may include a material that causes the positive electrode active material, solid electrolyte, and conductive material included in the positive electrode active material layer 120 to adhere to each other and improves the adhesion between the positive electrode active material layer 120 and the positive electrode current collector 110. The adhesive may include at least one of, for example, polyvinylidene fluoride, styrene-butadiene rubber (SBR), polytetrafluoroethylene, polyethylene, polyvinyl alcohol, polyvinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, and polymethyl methacrylate.

[0050] In the positive electrode active material layer 120, the positive electrode active material may be included in an amount ranging from about 85 parts by weight to about 92 parts by weight, relative to the total of 100 parts by weight of the positive electrode active material, solid electrolyte, conductive material, and binder. The binder may be included in the positive electrode active material layer 120 in an amount ranging from about 0.5 parts by weight to about 1.5 parts by weight.

[0051] In the positive electrode active material layer 120, the conductive material may be present in an amount ranging from about 1 part by weight to about 50 parts by weight relative to 100 parts by weight of the solid electrolyte. When the conductive material is present in an amount less than about 1 part by weight relative to 100 parts by weight of the solid electrolyte, the conductivity of the positive electrode active material layer 120 may decrease. When the conductive material is present in an amount greater than about 50 parts by weight relative to 100 parts by weight of the solid electrolyte, the proportion of the conductive material may increase significantly, resulting in incomplete formation of the coating covering the surface of the solid electrolyte.

[0052] According to some example embodiments, in addition to the positive electrode active material, solid electrolyte, conductive material and binder, the positive electrode active material layer 120 may also include at least one additive, such as or including at least one of filler, coating agent, dispersant and ionic conductive agent.

[0053] A solid electrolyte layer 300 may be disposed between the positive electrode layer 100 and the negative electrode layer 200, and may include a sulfide-based solid electrolyte with desired or improved lithium-ion conductivity. The solid electrolyte included in the solid electrolyte layer 300 may include the same or different materials as those included in the solid electrolyte included in the positive electrode active material layer 120.

[0054] In an example embodiment, the solid electrolyte layer 300 may include a sulfide-based solid electrolyte. The sulfide-based solid electrolyte can be prepared, for example, by melting and quenching or mechanically grinding a starting material such as Li₂S or P₂S₅. Additionally, the resulting product may be heat-treated after the above treatment. The solid electrolyte may be in an amorphous state, a crystalline state, or a mixture of amorphous and crystalline states. The solid electrolyte may include at least one of the component elements included in the above-described sulfide-based solid electrolyte: sulfur (S), phosphorus (P), and lithium (Li). For example, the solid electrolyte may be or include a material containing Li₂S-P₂S₅. When a material containing Li₂S-P₂S₅ is included as a sulfide-based solid electrolyte material in the solid electrolyte, the molar ratio of Li₂S and P₂S₅ may be in the range of about 50:50 to about 90:10.

[0055] Sulfide solid electrolytes may be or include argentite-germanium sulfide compounds, such as Li 7-x PS 6-x Cl x (where 0≤x≤2), Li 7-x PS 6-x Br x (where 0 ≤ x ≤ 2) and Li 7-x PS 6-x I x (where 0 ≤ x ≤ 2) at least one of the following. For example, sulfide solid electrolytes may be or include argentite-germanium sulfide compounds, which include at least one of Li6PS5Cl, Li6PS5Br and Li6PS5I.

[0056] In another example, the sulfide-based solid electrolyte may be or include a sulforaph-germanium ore type compound, which includes Li 7-a M a PS 6-c X c(Where 0 ≤ a ≤ 2 and 0 ≤ c ≤ 2). In the above chemical formula, X can be or includes at least one of F, Br, Cl, and combinations thereof. Additionally, M can be or includes at least one of scandium (Sc), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), zinc (Zn), cadmium (Cd), mercury (Hg), aluminum (Al), gallium (Ga), indium (In), thallium (Tl), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), arsenic (As), antimony (Sb), bismuth (Bi), and combinations thereof.

[0057] The sulfide-germanium ore type solid electrolyte can have a density in the range of about 1.5 g / cc to about 2.0 g / cc. Since the sulfide-germanium ore type solid electrolyte has a density equal to or greater than about 1.5 g / cc, the internal resistance of the all-solid-state battery can be reduced, and short circuits in the solid electrolyte layer and penetration caused by lithium dendrite formation can be hindered or prevented. The solid electrolyte can have an elastic modulus, for example, in the range of about 15 GPa to about 35 GPa.

[0058] The solid electrolyte layer 300 may also include a binder. The binder included in the solid electrolyte layer 300 may include, for example, at least one of styrene-butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, and polyethylene, but this disclosure is not limited thereto. The binder of the solid electrolyte layer 300 may be the same as or similar to the binder of the positive electrode active material layer 120 or the binder of the negative electrode coating 220 discussed below.

[0059] The negative electrode layer 200 may include a negative electrode current collector 210 and a negative electrode coating 220 on the negative electrode current collector 210. The negative electrode current collector 210 may provide a reference surface on which the negative electrode coating 220 is disposed. The negative electrode current collector 210 may include a material that does not react with lithium or substantially does not react with lithium, such as a material that does not form alloys or compounds with lithium. For example, the negative electrode current collector 210 may include at least one of copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), and nickel (Ni). The thickness of the negative electrode current collector 210 may be in the range of about 1 μm to about 20 μm, for example, about 5 μm to about 15 μm or about 7 μm to about 10 μm.

[0060] The negative electrode current collector 210 may be formed of one of the aforementioned metals, an alloy of two or more of the aforementioned metals, or a coating material, or may include one of the aforementioned metals, an alloy of two or more of the aforementioned metals, or a coating material. The negative electrode current collector 210 may have, for example, a plate shape or a foil shape. In the example embodiment, the negative electrode current collector 210 may be omitted.

[0061] When the single cell is MNC charged, the negative electrode coating 220 can induce the growth of lithium metal between the negative electrode coating 220 and the negative electrode current collector 210. The negative electrode coating 220 can be configured as a protective layer for lithium metal and can simultaneously reduce or suppress the precipitation and growth of lithium dendrites.

[0062] The negative electrode coating 220 may include metals and carbon. For example, the negative electrode coating 220 may include at least one selected from magnesium (Mg), gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn). The negative electrode coating 220 may include at least one selected from carbon black, acetylene black, furnace black, Ketjen black, and graphene. In an example embodiment, the negative electrode coating 220 may include a mixture of carbon black and silver (Ag).

[0063] In addition to metals and carbon, the negative electrode coating 220 may also include additives. The negative electrode coating 220 may include at least one of, for example, binders, fillers, coating agents, dispersants, and ionic conductive agents.

[0064] The thickness of the negative electrode coating 220 can be less than the thickness of the positive electrode active material layer 120. For example, the thickness of the negative electrode coating 220 can be equal to or less than about 50%, equal to or less than about 40%, equal to or less than about 30%, equal to or less than about 20%, equal to or less than about 10%, or equal to or less than about 5% of the thickness of the positive electrode active material layer 120. The negative electrode coating 220 can have a thickness in the range of, for example, about 1 μm to about 20 μm, about 2 μm to about 10 μm, or about 3 μm to about 7 μm. When the negative electrode coating 220 has a relatively small thickness, lithium dendrites formed between the negative electrode coating 220 and the negative electrode current collector 210 may cause the negative electrode coating 220 to collapse, thereby reducing the cycle characteristics of the single-cell MNC. When the negative electrode coating 220 has a relatively large thickness, the single-cell MNC may have a reduced energy density and increased internal resistance caused by the negative electrode coating 220, thereby reducing the cycle characteristics of the single-cell MNC.

[0065] Although not shown, a carbon layer may be further included to increase the adhesion between the negative electrode coating 220 and the solid electrolyte layer 300.

[0066] According to some exemplary embodiments of this disclosure, the width of the positive electrode layer 100 may be smaller than the width of the negative electrode layer 200. For example, the positive electrode layer 100 may have a first width W1 in the first direction D1, and the negative electrode layer 200 may have a second width W2 in the first direction D1. The first width W1 may be smaller than the second width W2. Since the first width W1 is smaller than the second width W2, a gasket may also be provided on the outer periphery of the positive electrode layer 100 to compensate for the width difference.

[0067] According to some exemplary embodiments of this disclosure, the solid electrolyte layer 300 may include a positive electrode solid electrolyte layer 300a and a negative electrode solid electrolyte layer 300b. The positive electrode solid electrolyte layer 300a and the negative electrode solid electrolyte layer 300b may be stacked to form the solid electrolyte layer 300. The positive electrode solid electrolyte layer 300a may be in contact with the positive electrode active material layer 120, and the negative electrode solid electrolyte layer 300b may be in contact with the negative electrode coating 220.

[0068] For example, the positive electrode solid electrolyte layer 300a and the negative electrode solid electrolyte layer 300b may have the same composition of solid electrolyte. Alternatively, the positive electrode solid electrolyte layer 300a and the negative electrode solid electrolyte layer 300b may include solid electrolytes with different compositions from each other.

[0069] The positive electrode solid electrolyte layer 300a may have a first width W1, and the negative electrode solid electrolyte layer 300b may have a second width W2. For example, the width of the positive electrode solid electrolyte layer 300a may be smaller than the width of the negative electrode solid electrolyte layer 300b. The first width W1 of the positive electrode solid electrolyte layer 300a may be smaller than the second width W2 of the negative electrode solid electrolyte layer 300b. Since the first width W1 of the positive electrode solid electrolyte layer 300a is smaller than the second width W2 of the negative electrode solid electrolyte layer 300b, a gasket may also be provided on the outer periphery of the positive electrode solid electrolyte layer 300a to compensate for the width difference.

[0070] Still refer to Figure 1 The negative electrode layer 200 and the negative electrode solid electrolyte layer 300b can constitute the first electrode layer ETL1. The positive electrode layer 100 and the positive electrode solid electrolyte layer 300a can constitute the second electrode layer ETL2.

[0071] Figure 2 A plan view illustrating an all-solid-state battery according to some example embodiments of the present disclosure is shown. (Refer to...) Figure 1 and Figure 2 The positive electrode solid electrolyte layer 300a may have a first width W1 in the first direction D1. The negative electrode solid electrolyte layer 300b may have a second width W2 in the first direction D1. The first width W1 may be smaller than the second width W2.

[0072] The difference between the second width W2 and the first width W1 can be equal to or less than about 10 mm. For example, the difference between the second width W2 and the first width W1 can be equal to or less than about 8 mm, equal to or less than about 5 mm, or equal to or less than about 3 mm. The difference between the second width W2 and the first width W1 can be equal to or greater than about 0.1 mm, equal to or greater than about 0.5 mm, or equal to or greater than about 1 mm. When the width difference is greater than the above ranges, the size of the positive electrode layer 100 may be relatively reduced, thereby reducing the discharge capacity and energy density of the all-solid-state battery 10. When the width difference is less than the above ranges, it may be difficult to reduce or suppress the formation of lithium dendrites in the negative electrode, and therefore there may be a possibility of a short circuit.

[0073] The ratio (W2 / W1) of the second width W2 to the first width W1 can be in the range of about 1 to about 1.6. For example, the ratio (W2 / W1) of the second width W2 to the first width W1 can be in the range of about 1 to about 1.5, about 1 to about 1.4, about 1 to about 1.3, about 1 to about 1.2 or about 1 to about 1.1.

[0074] When the ratio (W2 / W1) of the second width W2 to the first width W1 is greater than the range described above, the all-solid-state battery 10 may have a reduced energy density.

[0075] Still refer to Figure 1 and Figure 2 The positive electrode solid electrolyte layer 300a may have a third width W3 in the second direction D2. The negative electrode solid electrolyte layer 300b may have a fourth width W4 in the second direction D2. The third width W3 may be smaller than the fourth width W4.

[0076] The difference between the third width W3 and the fourth width W4 can be equal to or less than approximately 10 mm. For example, the difference between the third width W3 and the fourth width W4 can be equal to or less than approximately 8 mm, equal to or less than approximately 5 mm, or equal to or less than approximately 3 mm. The difference between the third width W3 and the fourth width W4 can be equal to or greater than approximately 0.1 mm, equal to or greater than approximately 0.5 mm, or equal to or greater than approximately 1 mm. When the width difference is greater than the above ranges, the size of the positive electrode layer 100 may be relatively reduced, thereby decreasing the discharge capacity and energy density of the all-solid-state battery 10. When the width difference is less than the above ranges, it may be difficult to reduce or suppress the formation of lithium dendrites in the negative electrode, and therefore there may be a possibility of a short circuit.

[0077] The ratio of the fourth width W4 to the third width W3 (W4 / W3) can be in the range of about 1 to about 1.6. For example, the ratio of the fourth width W4 to the third width W3 (W4 / W3) can be in the range of about 1 to about 1.5, about 1 to about 1.4, about 1 to about 1.3, about 1 to about 1.2 or about 1 to about 1.1.

[0078] When the ratio of the fourth width W4 to the third width W3 (W4 / W3) is greater than the range mentioned above, the all-solid-state battery 10 may have a reduced energy density.

[0079] Figure 3 A cross-sectional view illustrating an all-solid-state battery according to some example embodiments of the present disclosure is shown. (Refer to...) Figure 3 An all-solid-state battery may include a positive electrode layer AL, a negative electrode layer CL, and a solid electrolyte layer SE between the positive electrode layer AL and the negative electrode layer CL. The solid electrolyte layer SE may be formed on the negative electrode layer CL. Additionally, the positive electrode layer AL may be formed on the solid electrolyte layer SE.

[0080] The positive electrode layer AL may include the positive electrode active material AM, binder BND, and lubricant additive LM, as discussed below (see below). Figure 5 or Figure 6 The positive electrode active material AM and the binder BND can be combined with the above-mentioned... Figure 1 The positive electrode active material and binder discussed are the same. The following description focuses on the differences.

[0081] Lubricating additive LM can be included in the positive electrode layer AL. Figure 3 The positive electrode layer AL can be related to the above. Figure 1 The positive electrode layer 100 discussed is substantially the same or similar. The lubricating additive LM may be further included in the positive electrode active material layer within the positive electrode layer AL (see...). Figure 4 In AML).

[0082] like Figure 7 As shown, the negative electrode layer CL may include a negative electrode current collector COL2 and a negative electrode coating CCL on the negative electrode current collector COL2. Regarding the negative electrode layer CL, in addition to the above... Figure 1 Beyond the topics discussed, the following description focuses on the differences. Figure 3 The negative electrode layer CL can be with Figure 1 The negative electrode layer 200 is basically the same.

[0083] The negative electrode coating CCL may include at least one of magnesium (Mg), gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn) and zinc (Zn), as well as at least one of carbon black, acetylene black, furnace black, Ketjen black and graphene.

[0084] The solid electrolyte layer (SE) can be located between the positive electrode layer (AL) and the negative electrode layer (CL). The description of the solid electrolyte layer (SE) can be as described above. Figure 1 As stated above. Figure 3 The solid electrolyte layer SE can interact with Figure 1 The solid electrolyte layer 300 is basically the same.

[0085] The solid electrolyte layer (SE) may include a solid electrolyte and a lubricating additive (LM).

[0086] The lubricating additive LM may be included in the positive electrode active material layer AML or the solid electrolyte layer SE. Optionally, the lubricating additive LM may be included in both the positive electrode active material layer AML and the solid electrolyte layer SE.

[0087] The electrode may include a lubricating additive LM to increase the fluidity of the electrode plate. It may also include a lubricating additive LM to increase the fluidity of the positive electrode layer AL. Additionally, it may include a lubricating additive LM to increase the fluidity of the solid electrolyte layer SE. Increased electrode plate fluidity can prevent the electrode plate from breaking or detaching after the pressing process. Furthermore, increased electrode plate fluidity can lead to dense bonding of the positive electrode layer AL or the solid electrolyte layer SE even without pressing under high pressure. The electrode plate may refer to the positive electrode layer AL, the solid electrolyte layer SE, or a combination of the positive electrode layer AL, the solid electrolyte layer SE, and the negative electrode layer CL.

[0088] The lubricant additive LM can be or includes materials that are non-volatile, non-reactive, and formable. Electrode plates containing the lubricant additive LM can exhibit flowability compared to electrode plates without it. The lubricant additive LM can exist in the form of solid particles at room temperature. Furthermore, the lubricant additive LM can behave like a soft solid or liquid at temperatures above a given point. This is discussed below regarding... Figure 5 and Figure 6 Let's have a discussion.

[0089] Lubricating additives LM may include compounds containing repeating units represented by chemical formula 1, compounds containing repeating units represented by chemical formula 2, or combinations thereof.

[0090] Chemical Formula 1:

[0091] In chemical formula 1, n can be an integer in the range of 1 to 100. Alternatively, n can be an integer in the range of 5 to 100, 5 to 50, or 5 to 20.

[0092] R1 may include hydroxyl, methyl, amino, acryloyl, phenyl, acrylonitrile, amide, alkyl, or carboxyl groups.

[0093] Chemical formula 2:

[0094] In chemical formula 2, m can be an integer in the range of 1 to 100. Alternatively, m can be an integer in the range of 5 to 100, 5 to 50, or 5 to 20.

[0095] In chemical formula 1 and chemical formula 2, "— "Can indicate the position where a given functional group (or substituent) is bonded."

[0096] The lubricant additive LM may include at least one of paraffin wax, low molecular weight polyethylene oxide (PEO), low molecular weight polyethylene (PE), low molecular weight polypropylene (PP), hexadecane, octadecane, tetracosanoic acid, eicosane, triacontane, and polyalphaolefin (PAO). Low molecular weight polyethylene oxide (PEO) and low molecular weight polyethylene (PE) may each have a carbon number ranging from 5 to 20.

[0097] The lubricating additive LM may further comprise a lithium salt. The lithium salt may be included in all-solid-state batteries or rechargeable lithium batteries. The lubricating additive LM may be dielectric, therefore, when the lubricating additive LM is added to the electrode plates, a lithium salt may be included to improve conductivity. For example, the lithium salt may include LiSCN, LiN(CN)2, Li(CF3SO2)3C, LiC4F9SO3, LiN(SO2CF2CF3)2, LiPF3(C2F5)3, LiCl, LiF, LiBr, LiI, LiPF6, LiPF5(CF3), LiPF5(C2F5), LiPF5(C3F7), LiPF4(CF3)2, LiPF4(CF3)(C2F5), LiPF(CF3)3, LiPF3(CF2CF3)3 At least one of LiPF4(C2O4)2, LiBF4, LiBF3(C2F5), lithium bis(oxalate)borate (LiB(C2O4)2, LiBOB), lithium difluorooxalateborate (LiODFB), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI, LiN(SO2CF3)2), lithium bis(fluorosulfonyl)imide (LiFSI, LiN(SO2F)2), LiN(SO2C2F5)2, LiCF3SO3, LiAsF6, LiSbF6 and LiClO4.

[0098] The molecular weight of the lubricant additive LM can be in the range of about 100 g / mol to about 3,000 g / mol, about 100 g / mol to about 2,000 g / mol, or about 200 g / mol to about 2,000 g / mol.

[0099] Lubricant additives (LM) can have a coefficient of friction in the range of about 0.01 to about 0.1. The coefficient of friction of lubricant additives (LM) can be measured by, for example, a tribometer, the inclined plane method, or the pin-on-disk method.

[0100] The coefficient of friction can be defined as the ratio of the frictional force that occurs when two surfaces are in contact to the force acting perpendicularly to the surfaces.

[0101] A tribometer can be a device that measures friction by preparing a surface coated with a lubricant to be tested and another surface in contact with said one surface, and then causing relative motion between the two surfaces.

[0102] The inclined plane method is a way to measure the coefficient of friction by placing an object on an inclined surface coated with lubricant and gradually increasing the angle of the inclined surface until the object begins to move. The angle at which the object begins to move is used to determine the coefficient of friction.

[0103] The pin-disc method involves contacting a lubricated pin with the surface of a rotating disk to measure the frictional force generated during rotation. The measured frictional force can then be used to determine the coefficient of friction.

[0104] The lubricating additive LM can have a coefficient of friction in the range of about 0.01 to about 0.1. For example, the coefficient of friction of the lubricating additive LM can be in the range of about 0.04 to about 0.1, about 0.05 to about 0.1, or about 0.05 to about 0.08.

[0105] Under the same temperature conditions, an increase in the coefficient of friction of lubricant LM may lead to an increase in its viscosity. Conversely, under the same temperature conditions, a decrease in the coefficient of friction of lubricant LM may lead to a decrease in its viscosity. Therefore, an increase in the coefficient of friction of lubricant LM may result in a decrease in the fluidity of the electrode plate to which lubricant LM has been added.

[0106] Figure 4 A cross-sectional view of the positive electrode layer AL of an all-solid-state battery according to some example embodiments of the present disclosure is shown. (Refer to...) Figure 4 The positive electrode layer AL may include a positive electrode current collector COL1 and a positive electrode active material layer AML on the positive electrode current collector COL1. The positive electrode active material layer AML may include a positive electrode active material AM, a binder BND, and a lubricating additive LM (see [link to documentation]). Figure 5 or Figure 6 ).

[0107] The positive electrode active material AM and the binder BND can be combined with the above-mentioned... Figure 1 and Figure 3The positive electrode active material and binder discussed are the same. (Still refer to...) Figure 4 The lubricating additive LM can be present in the positive electrode active material layer AML in an amount ranging from about 0.1 wt% to about 1.0 wt%. Additionally, the lubricating additive LM can be present in the positive electrode active material layer AML in an amount ranging from about 0.5 wt% to about 1.0 wt%, but this disclosure is not limited thereto. When the lubricating additive LM in the positive electrode active material layer AML is included in an amount greater than about 1.0 wt%, the resistance in the positive electrode active material layer AML may increase, thereby reducing the performance of the all-solid-state battery. Furthermore, when the lubricating additive LM in the positive electrode active material layer AML is included in an amount equal to or less than about 0.1 wt%, the flowability of the positive electrode active material layer AML may decrease, and the pressing process may not be able to be performed at low pressure.

[0108] Figure 5 It shows Figure 4 The image depicts a magnified view of portion M1 before pressing the positive electrode layer AL according to some exemplary embodiments of this disclosure. (See also...) Figure 4 and Figure 5 The lubricating additive LM can exist as solid particles between the positive electrode active material AM at room temperature. For example, in Figure 5 In this process, the positive electrode slurry including the lubricating additive LM or the positive electrode active material can be separately included in the positive electrode active material layer AML. Additionally, the lubricating additive in the positive electrode active material layer AML can be spaced apart from the positive electrode active material AM at room temperature. Then, during a rolling process at a temperature range of approximately 60°C or higher, the lubricating additive LM can be converted to a liquid or similar state.

[0109] Figure 6 It shows Figure 4 A magnified view of portion M1 after roll forming of the positive electrode active material layer AML at a temperature in the range of approximately 60°C or higher. The lubricant additive LM can exist in a liquid state at a temperature in the range of approximately 43°C to approximately 60°C. For example, the melting point of the lubricant additive LM can be in the range of approximately 43°C to approximately 60°C. Therefore, the lubricant additive LM can exist in the form of solid particles at room temperature and in a liquid state at a temperature in the range of approximately 60°C or higher, which can cause an increase in the fluidity of the positive electrode active material layer AML or the solid electrolyte layer SE.

[0110] Figure 6 Depicting Figure 4 The image depicts a magnified view of portion M1 after pressing the positive electrode active material layer AML according to some example embodiments of the present disclosure. Figure 6The positive electrode active material layer AML shown can be an enlarged view of a portion of M1 after being pressed using a roll forming method. When pressing the positive electrode active material layer AML using a roll forming method, the pressing temperature can be equal to or greater than approximately 60°C. For example, the temperature used for the roll forming process can be greater than the melting point of the lubricant additive LM. (Refer to...) Figure 5 and Figure 6 The rolling process can be carried out at a temperature equal to or greater than the melting point of the lubricant additive LM, allowing the lubricant additive LM, in solid particle form, to be coated onto each positive electrode active material AM. For example, when the temperature is equal to or greater than the melting point of the lubricant additive LM, the lubricant additive LM, existing in solid particle form at room temperature, can be distributed substantially uniformly throughout the particles of the positive electrode active material AM. Furthermore, when the temperature is equal to or greater than the melting point of the lubricant additive LM, the lubricant additive LM, existing in solid particle form at room temperature, can form a coating on the surface of the particles of the positive electrode active material AM.

[0111] The lubricant LM can achieve a substantially uniform distribution across the particles of the positive electrode active material AM, and can provide flowability between the positive electrode active material layer AML and the positive electrode active material AM. Therefore, even under low pressure pressing, the positive electrode active material layer AML containing the lubricant LM can increase the flowability and formability of the electrode plate, facilitating tight adhesion between the solid electrolyte layer SE and the positive electrode active material layer AML. For example, the adhesion between the positive electrode active materials AM can be increased due to the lubricant LM coated on the particle surface of the positive electrode active material AM. Additionally, the adhesion between the solid electrolyte particles can be increased due to the lubricant LM included in the solid electrolyte layer SE. Furthermore, the lubricant LM can increase the adhesion between the solid electrolyte particles and the positive electrode active material AM in the region where the positive electrode layer AL and the solid electrolyte layer SE are in contact.

[0112] Although not shown, the lubricating additive LM can even be included in the solid electrolyte layer SE. Therefore, similar to... Figure 6 The description in the text includes the lubricating additive LM in the solid electrolyte layer SE, which can be distributed substantially uniformly throughout the solid electrolyte particles and can be combined with the above-mentioned... Figures 4 to 6 The lubricating additive LM discussed is the same. For example, the lubricating additive LM may be present in the solid electrolyte layer SE in an amount ranging from about 0.1 wt% to about 1.0 wt%.

[0113] Figure 7A cross-sectional view illustrating a negative electrode layer CL according to some example embodiments of the present disclosure is shown. The negative electrode layer CL may include a negative electrode current collector COL2 and a negative electrode coating CCL on the negative electrode current collector COL2. The negative electrode coating CCL may include at least one selected from magnesium (Mg), gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn), and at least one selected from carbon black, acetylene black, furnace black, Ketjen black, and graphene. The negative electrode current collector COL2 and the negative electrode coating CCL may be related to the above-mentioned... Figure 1 The negative electrode current collector and negative electrode coating discussed are the same.

[0114] Figure 8 A conceptual diagram illustrating the pressing steps for manufacturing an all-solid-state battery according to some example embodiments of the present disclosure is shown. (Refer to...) Figure 8 A single-cell MNC can be pressed by a pair of rollers RL. A single-cell MNC can be a cell stack.

[0115] As mentioned above Figure 5 and Figure 6 The rollers RL discussed may include a heating device (not shown) for increasing temperature. The heating device can be any suitable device capable of heating the rollers RL. Since the all-solid-state batteries according to some example embodiments of this disclosure include a lubricating additive LM, flowability and formability can be increased to reduce the pressure applied from the rollers RL. For example, the pressing pressure according to this disclosure can be less than the pressing pressure applied in typical rolling methods for manufacturing all-solid-state batteries. The addition of the lubricating additive LM can increase the adhesion between the positive electrode active material layer AML and the solid electrolyte layer SE, or between the negative electrode layer CL and the solid electrolyte layer SE, allowing the stacked structure to be assembled even at lower pressures.

[0116] Figure 9 This is a flowchart illustrating a method for manufacturing an all-solid-state battery according to some example embodiments of the present disclosure. (Refer to...) Figure 9 According to some example embodiments of this disclosure, a method for manufacturing an all-solid-state battery may include the following steps: mixing a positive electrode active material AM, a binder BND, and a lubricating additive LM to prepare a positive electrode slurry (S100); coating the positive electrode slurry onto a positive electrode current collector COL1 to form a positive electrode active material layer AML (S200); stacking (e.g., sequentially stacking) a solid electrolyte layer SE and a negative electrode layer CL on the positive electrode active material layer AML (S300); and rolling the stacked structure (S400).

[0117] The forming step S200 may include performing a rolling process.

[0118] The stacking (e.g., sequential stacking) step S300 may include stacking and rolling a solid electrolyte layer SE on the positive electrode active material layer AML.

[0119] The stacking (e.g., sequential stacking) step S300 may also include stacking and rolling the negative electrode layer CL on the solid electrolyte layer SE.

[0120] Preparation step S100 may include providing a compound comprising repeating units represented by chemical formula 1, a compound comprising repeating units represented by chemical formula 2, or a combination thereof. The description of the lubricant additive LM can be as described above regarding... Figure 2 The subject of discussion.

[0121] Forming step S200 may include using any method for coating a positive electrode slurry onto the positive electrode current collector COL1. For example, forming step S200 may include a typical method for manufacturing a rechargeable lithium battery or an all-solid-state battery in which a positive electrode slurry is coated onto the positive electrode current collector COL1. However, unlike the typical method, a lubricating additive LM may be included in the positive electrode slurry coated onto the positive electrode current collector COL1. Additionally, the coating of the positive electrode slurry onto the positive electrode current collector COL1 may be performed at room temperature. In an example embodiment, coating the positive electrode slurry onto the positive electrode current collector COL1 may be performed at a temperature equal to or less than the melting point of about the lubricating additive LM. For example, the coating of the positive electrode slurry onto the positive electrode current collector COL1 may be performed at a temperature less than about 100°C. If the lubricating additive LM is included in the solid electrolyte layer SE, the coating process may also be performed at room temperature.

[0122] The stacking (e.g., sequential stacking) step S300 can be the same as a typical method for manufacturing an all-solid-state battery. For example, a solid electrolyte layer SE can be stacked on a positive electrode active material layer AML, and then a negative electrode layer CL can be stacked on the solid electrolyte layer SE. However, this disclosure is not limited thereto. For example, the stacking (e.g., sequential stacking) step S300 may include the following steps: stacking a positive electrode solid electrolyte layer on a positive electrode active material layer to form a positive electrode stack structure; applying a first pressure after stacking the positive electrode solid electrolyte layer on the positive electrode active material layer; stacking a negative electrode solid electrolyte layer on a negative electrode layer to form a negative electrode stack structure; and applying a second pressure after stacking the negative electrode solid electrolyte layer on a negative electrode layer, wherein the first pressure may be greater than the second pressure. The application of the first and second pressures may be performed at temperatures in the range of about 100°C to about 200°C.

[0123] The rolling step S400 may include rolling a stacked positive electrode active material layer AML, a solid electrolyte layer SE, and a negative electrode layer CL. For example, the stacked structure may be similar to the one described above. Figure 1The single-cell MNC discussed is the same.

[0124] When pressing stacked structures using a roll pressing method, the rolls can be at temperatures above room temperature. For example, the roll pressing of stacked structures can be carried out at temperatures ranging from about 60°C to about 150°C. These temperature conditions can be provided to achieve a liquid state for the lubricating additive LM, which is included in one or both of the positive electrode active material layer AML and the solid electrolyte layer SE. For example, a temperature above the melting point of the lubricating additive LM can be maintained to increase the fluidity of one or both of the positive electrode active material layer AML and the solid electrolyte layer SE, where the lubricating additive LM is included in each of the positive electrode active material layer AML and the solid electrolyte layer SE. Therefore, even at low pressures, heated rolls can press stacked structures to manufacture all-solid-state batteries. For example, the roll pressing of stacked structures can be carried out at pressures ranging from about 0.05 tons / cm to about 2.5 tons / cm.

[0125] When the lubricating additive according to some example embodiments of this disclosure is included in one or both of the positive electrode layer and the solid electrolyte layer, the fluidity of the electrode plate can be increased to improve the formability of the all-solid-state battery.

[0126] Furthermore, the positive electrode layer or solid electrolyte layer containing lubricating additives can have increased adhesion, so that the solid electrolyte can easily adhere to the positive electrode layer or negative electrode layer even in the pressing process under low pressure.

[0127] Although some exemplary embodiments of the present disclosure have been discussed with reference to the accompanying drawings, it is understood that various changes in form and detail may be made therein without departing from the spirit and scope of the present disclosure. It will be apparent to those skilled in the art that various substitutions, modifications, and alterations may be made therein without departing from the scope and spirit of the present disclosure.

[0128] Example 1 A positive electrode active material, binder, and lubricant additive are mixed to prepare a positive electrode slurry. Paraffin wax with a carbon content between 18 and 40 is included as a lubricant additive. The lubricant additive is adjusted to have an amount of about 0.3 wt% in the positive electrode slurry. The positive electrode slurry containing the lubricant additive is coated onto a positive electrode current collector to fabricate a positive electrode layer. A solid electrolyte layer and a negative electrode layer are stacked on the fabricated positive electrode layer, and then pressed using a rolling method at a temperature of about 100°C and a pressure of about 0.05 t / cm to 2.5 t / cm.

[0129] Example 2 A positive electrode active material, binder, and lubricating additive are mixed to prepare a positive electrode slurry. Polyethylene oxide (PEO) having between 20 and 25 repeating monomer units is included as a lubricating additive. The lubricating additive is adjusted to an amount of about 0.3 wt% in the positive electrode slurry. The positive electrode slurry containing the lubricating additive is coated onto a positive electrode current collector to fabricate a positive electrode layer. A solid electrolyte layer and a negative electrode layer are stacked on the fabricated positive electrode layer, and then pressed using a rolling method at a temperature of about 100°C and a pressure of about 0.05 t / cm to 2.5 t / cm.

[0130] Comparative Example 1 A positive electrode active material and a binder are mixed to prepare a positive electrode slurry. The positive electrode slurry does not contain lubricating additives. The prepared positive electrode slurry is then coated onto a positive electrode current collector to create a positive electrode layer.

[0131] evaluate The compression characteristics of the positive electrode layers manufactured in Examples 1 to 2 and Comparative Example 1 were evaluated.

[0132] The compressibility characteristics were evaluated by measuring the density of the mixture under different rolling pressures ranging from approximately 0.05 t / cm to 2.5 t / cm.

[0133] Electrode plates can refer to either the positive electrode layer or the solid electrolyte layer.

[0134] Table 1:

[0135] Refer to Table 1 and Figure 10 It can be observed that increasing the amount of lubricating additive leads to improved compressibility of the positive electrode layer. For example, a significant difference in compressibility between the positive electrode layer containing the lubricating additive and the positive electrode layer without the lubricating additive can be observed in the range of mixture density from about 2.9 g / cc to about 3.5 g / cc. This indicates that the electrode plate containing the lubricating additive exhibits increased compressibility under low linear pressure.

[0136] Furthermore, it can be determined that when the density of the mixture containing the positive electrode layer or solid electrolyte layer with lubricating additive is in the range of about 2.9 g / cc to about 3.5 g / cc, the compression characteristics are most desirable or improved when the lubricating additive is included in an amount in the range of about 0.1 wt% to about 1.0 wt%.

[0137] The all-solid-state battery according to this disclosure can be manufactured by a pressing process under low pressure, by adjusting the formability of the electrode plates according to temperature.

[0138] In the method for manufacturing all-solid-state batteries according to this disclosure, the stability of the electrode plates is ensured while the rolling temperature is changed, making it easy to form and assemble the electrode plates even at low pressure, thereby promoting the production of all-solid-state batteries.

Claims

1. An all-solid-state battery, the all-solid-state battery comprising: Positive electrode layer; Negative electrode layer; as well as A solid electrolyte layer is located between the positive electrode layer and the negative electrode layer. Wherein, at least one of the positive electrode layer and the solid electrolyte layer includes a lubricating additive, and The lubricating additive includes one of the following: The first compound includes a repeating unit represented by chemical formula 1; The second compound includes a repeating unit represented by chemical formula 2; and The combination of the first compound and the second compound, Chemical Formula 1: In formula 1, n is an integer between 1 and 100, and R1 includes hydroxyl, methyl, amino, acryloyl, phenyl, acrylonitrile, amide, alkyl, or carboxyl groups. Chemical formula 2: In chemical formula 2, m is an integer between 1 and 100.

2. The all-solid-state battery according to claim 1, wherein: In chemical formula 1, n is an integer in the range between 5 and 50, and In chemical formula 2, m is an integer in the range of 5 to 50.

3. The all-solid-state battery according to claim 1, wherein, The lubricating additive includes at least one of paraffin wax, low molecular weight polyethylene oxide, low molecular weight polyethylene, low molecular weight polypropylene, hexadecane, octadecane, tetracosanoic acid, eicosane, triacontane, and polyalphaolefin.

4. The all-solid-state battery according to claim 1, wherein, The positive electrode layer includes: Positive electrode current collector; and The positive electrode active material layer is located on the positive electrode current collector. The positive electrode active material layer includes a positive electrode active material, a binder, and the lubricating additive. The amount of the lubricating additive in the positive electrode active material layer is in the range of 0.1 wt% to 1.0 wt%.

5. The all-solid-state battery according to claim 4, wherein, The adhesive includes at least one of styrene-butadiene rubber, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polyvinyl alcohol, polyvinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, and polymethyl methacrylate.

6. The all-solid-state battery according to claim 1, wherein, The lubricating additive further includes lithium salts, wherein the lithium salts include LiSCN, LiN(CN)2, Li(CF3SO2)3C, LiC4F9SO3, LiN(SO2CF2CF3)2, LiPF3(C2F5)3, LiCl, LiF, LiBr, LiI, LiPF6, LiPF5(CF3), LiPF5(C2F5), LiPF5(C3F7), LiPF4(CF3)2, and LiP. At least one of F4(CF3)(C2F5), LiPF(CF3)3, LiPF3(CF2CF3)3, LiPF4(C2O4)2, LiBF4, LiBF3(C2F5), lithium bis(oxalate)borate, lithium difluorooxalateborate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, LiN(SO2C2F5)2, LiCF3SO3, LiAsF6, LiSbF6 and LiClO4.

7. The all-solid-state battery according to claim 1, wherein, The solid electrolyte layer comprises a solid electrolyte, a binder, and the lubricating additive. The amount of the lubricating additive in the solid electrolyte layer is in the range of 0.1 wt% to 1.0 wt%.

8. The all-solid-state battery according to claim 7, wherein, The solid electrolyte layer includes a sulfosilver germanite-type solid electrolyte.

9. The all-solid-state battery according to claim 1, wherein, The negative electrode layer includes: Negative electrode current collector; and Negative electrode coating, on the negative electrode current collector, The negative electrode coating includes at least one of magnesium, gold, platinum, palladium, silicon, silver, aluminum, bismuth, tin, and zinc; and at least one of carbon black, acetylene black, furnace black, Ketjen black, and graphene.

10. An all-solid-state battery, the all-solid-state battery comprising: Positive electrode layer; Negative electrode layer; as well as A solid electrolyte layer is located between the positive electrode layer and the negative electrode layer. Wherein, at least one of the positive electrode layer and the solid electrolyte layer includes a lubricating additive, and The lubricating additive has a molecular weight in the range of 100 g / mol to 3,000 g / mol and a coefficient of friction in the range of 0.01 to 0.

1.

11. The all-solid-state battery according to claim 10, wherein, The positive electrode layer includes: Positive electrode current collector; and The positive electrode active material layer is located on the positive electrode current collector. The positive electrode active material layer includes a positive electrode active material, a binder, and the lubricating additive. The amount of the lubricating additive in the positive electrode active material layer is in the range of 0.1 wt% to 1.0 wt%.

12. The all-solid-state battery according to claim 10, wherein, The lubricating additive includes at least one of paraffin wax, low molecular weight polyethylene oxide, low molecular weight polyethylene, low molecular weight polypropylene, hexadecane, octadecane, tetracosanoic acid, eicosane, triacontane, and polyalphaolefin.

13. A method for manufacturing an all-solid-state battery, the method comprising the following steps: A positive electrode active material, binder, and lubricating additive are mixed to prepare a positive electrode slurry; The positive electrode slurry is coated onto the positive electrode current collector to form a positive electrode active material layer; as well as A solid electrolyte layer and a negative electrode layer are stacked on the positive electrode active material layer. The lubricating additive includes one of the following: The first compound includes a repeating unit represented by chemical formula 1; The second compound includes a repeating unit represented by chemical formula 2; and The combination of the first compound and the second compound, Chemical Formula 1: In chemical formula 1, n is an integer in the range between 1 and 100, and R1 includes hydroxyl, methyl, amino, acryloyl, phenyl, acrylonitrile, amide, alkyl, or carboxyl groups. Chemical formula 2: In chemical formula 2, m is an integer between 1 and 100.

14. The method according to claim 13, wherein, The lubricating additive includes at least one of paraffin wax, low molecular weight polyethylene oxide, low molecular weight polyethylene, low molecular weight polypropylene, hexadecane, octadecane, tetracosanoic acid, eicosane, triacontane, and polyalphaolefin.

15. The method according to claim 13, wherein, The amount of the lubricating additive included in the positive electrode active material layer is in the range of 0.1 wt% to 1.0 wt%.

16. The method according to claim 13, wherein, The step of stacking the solid electrolyte layer and the negative electrode layer on the positive electrode active material layer further includes the following step: rolling the stacked structure with the stacked positive electrode active material layer, the solid electrolyte layer and the negative electrode layer. The step of rolling the stacked structure is carried out at a temperature ranging from 60°C to 150°C.

17. The method according to claim 16, wherein, The rolling process of the stacked structure is carried out under a pressure ranging from 0.05 tons / cm to 2.5 tons / cm.

18. The method according to claim 13, wherein, The step of stacking the solid electrolyte layer and the negative electrode layer on the positive electrode active material layer includes the following steps: A positive electrode solid electrolyte layer is stacked on the positive electrode active material layer to form a positive electrode stack structure; A first pressure is applied after the positive electrode solid electrolyte layer is stacked on the positive electrode active material layer; A negative electrode solid electrolyte layer is stacked on the negative electrode layer to form a negative electrode stack structure; and A second pressure is applied after the negative electrode solid electrolyte layer is stacked on the negative electrode layer. Wherein, the first pressure is greater than the second pressure.

19. The method according to claim 18, wherein, The step of applying the first pressure is carried out at a temperature in the range of 100°C to 200°C.

20. The method according to claim 18, wherein, The step of applying the second pressure is carried out at a temperature in the range of 100°C to 200°C.

Images