All-solid-state battery and method for manufacturing same

Abstract

The present invention relates to an all-solid-state battery and a method for manufacturing same. More specifically, the all-solid-state battery of the present invention is a pouch-type all-solid-state battery comprising: an electrode assembly containing a solid electrolyte; and a pouch exterior material accommodating the electrode assembly, wherein the pouch exterior material includes a first exterior material and a second exterior material disposed to face each other to package the electrode assembly. The first exterior material forms a first exterior material region of the all-solid-state battery while surrounding at least a portion of the electrode assembly. The pouch exterior material includes a first wing portion formed by sealing the first and second exterior materials to each other. The first wing portion includes a first folding portion formed by folding, and the first folding portion does not protrude beyond the minimum driving thickness of the pouch-type all-solid-state battery.

Description

All-solid-state battery and method for manufacturing the same

[0001] The present invention relates to a pouch-type all-solid-state battery and a method for manufacturing the same.

[0002]

[0003] Recently, driven by industrial demands, the development of batteries with high energy density and safety 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.

[0004] Recently, all-solid-state batteries have been proposed in which the liquid electrolyte of lithium-ion batteries is replaced with a solid electrolyte. By not using flammable organic dispersion media, all-solid-state batteries can significantly reduce the likelihood of fire or explosion in the event of a short circuit. Therefore, such all-solid-state batteries can possess excellent safety.

[0005]

[0006] The problem that the present invention aims to solve is to provide a pouch-type all-solid-state battery capable of preventing interference between the folding part and / or the adhesive member during pressurized driving.

[0007] Another problem that the present invention aims to solve is to provide a method for manufacturing a pouch-type all-solid-state battery that can prevent interference between the folding part and / or the adhesive member during pressurized driving.

[0008]

[0009] A pouch-type all-solid-state battery according to the concept of the present invention comprises an electrode assembly containing a solid electrolyte and a pouch outer material that accommodates the electrode assembly, wherein the pouch outer material may include a first outer material and a second outer material arranged to face each other to enclose the electrode assembly. The first outer material may form a first outer material region of the all-solid-state battery while enclosing at least a portion of the electrode assembly. The pouch outer material may include a first wing portion formed by sealing the first and second outer materials together, and the first wing portion may include a first folding portion formed by folding. The first folding portion may be formed so as not to protrude beyond the minimum operating thickness of the pouch-type all-solid-state battery. The minimum operating thickness may be defined as the minimum thickness of the first outer material region.

[0010] A pouch-type all-solid-state battery according to another concept of the present invention is a pouch-type all-solid-state battery comprising an electrode assembly containing a solid electrolyte and a pouch outer material that accommodates the electrode assembly, wherein the pouch outer material may include a receiving portion in which the electrode assembly is accommodated, a first wing portion formed by sealing one side of the pouch outer material, and a second wing portion formed by sealing the other side of the pouch outer material. The first and second wing portions are spaced apart from each other in a first direction, and the first wing portion may include a first folding portion that is folded and protrudes in a third direction. The all-solid-state battery has a first thickness defined as the thickness in the third direction from the first wing portion, and the ratio of the length of the first folding portion in the third direction to the first thickness may be 0.4 to 0.8.

[0011] A pouch-type all-solid-state battery according to another concept of the present invention comprises an electrode assembly containing a solid electrolyte and a pouch outer material that accommodates the electrode assembly, wherein the pouch outer material may include a first outer material and a second outer material arranged to face each other to package the electrode assembly. The first outer material may form a first outer material region of the all-solid-state battery while enveloping at least a portion of the electrode assembly. The pouch outer material may include a first wing portion formed by sealing the first and second outer materials together, and the first wing portion may include a first folding portion formed by folding toward the first outer material region. The all-solid-state battery may include an adhesive member attached between the first folding portion and the first outer material region to fix the first folding portion, wherein the end portion of the adhesive member may not protrude beyond the minimum operating thickness of the first outer material region.

[0012] A pouch-type all-solid-state battery according to another concept of the present invention is a pouch-type all-solid-state battery comprising an electrode assembly containing a solid electrolyte and a pouch outer material that accommodates the electrode assembly, wherein the pouch outer material may include a receiving portion that accommodates the electrode assembly and a first wing portion formed by sealing one side of the pouch outer material. The first wing portion may include a first folding portion that is folded inward and protrudes in a third direction. The all-solid-state battery includes an adhesive member attached between the first folding portion and the outer surface of the receiving portion to fix the first folding portion, wherein the height difference between the end portion of the adhesive member and the upper and lower surfaces of the pouch-type all-solid-state battery may be 1 mm or more.

[0013] A method for manufacturing a pouch-type all-solid-state battery according to another concept of the present invention may comprise: packaging an electrode assembly in a pouch casing comprising a first casing and a second casing arranged to face each other; wherein the pouch casing comprises a gas pocket and a receiving portion in which the electrode assembly is received; sealing the outer edge of the pouch casing; sealing and cutting between the gas pocket and the receiving portion to form a first wing portion in which the first and second casings are sealed together; and folding the first wing portion to form a first folding portion. The first folding portion may not protrude beyond the minimum operating thickness of the pouch-type all-solid-state battery.

[0014] A method for manufacturing a pouch-type all-solid-state battery according to another concept of the present invention may include packaging an electrode assembly in a pouch casing comprising a first casing and a second casing arranged to face each other; wherein the pouch casing comprises a gas pocket and a receiving portion in which the electrode assembly is received; sealing the outer edge of the pouch casing; sealing and cutting between the gas pocket and the receiving portion to form a first wing portion in which the first and second casings are sealed together; folding the first wing portion to form a first folding portion; and fixing the first folding portion. The first casing wraps around the upper part of the electrode assembly to form a first casing region of the all-solid-state battery, and fixing the first folding portion includes attaching an adhesive member between the first folding portion and the first casing region, wherein the end portion of the adhesive member may not protrude beyond the minimum operating thickness of the pouch-type all-solid-state battery.

[0015] The pouch-type all-solid-state battery according to the present invention can prevent interference between the sealing and the folded portion during pressurized operation. Through this, the all-solid-state battery can be pressurized to a desired pressure, and consequently, cell performance can be improved.

[0016] The pouch-type all-solid-state battery according to the present invention can also prevent interference of the adhesive member.

[0017] Through the manufacturing method according to the present invention, a pouch-type all-solid-state battery can be manufactured that prevents interference between the adhesive member and the folding part when driven by pressure.

[0018]

[0019] FIG. 1 is a cross-sectional view of an all-solid-state battery according to embodiments of the present invention.

[0020] FIG. 2a is a diagram showing the state of housing an all-solid-state battery according to embodiments of the present invention in a pouch.

[0021] FIG. 2b is a schematic cross-section of a pouch-type all-solid-state battery.

[0022] FIGS. 3a and 3b are cross-sectional views illustrating problems that occur when a pouch-type all-solid-state battery is driven under pressure according to comparative examples.

[0023] FIG. 4 is a flowchart for explaining a method for manufacturing a pouch-type all-solid-state battery according to an embodiment of the present invention.

[0024] FIGS. 5a to 5e are plan or cross-sectional views for explaining a method for manufacturing a pouch-type all-solid-state battery according to one embodiment.

[0025] FIGS. 6a to 6d are plan or cross-sectional views for explaining a method for manufacturing a pouch-type all-solid-state battery according to another embodiment.

[0026] FIG. 7a is a cross-sectional view illustrating a pouch-type all-solid-state battery according to one embodiment. FIG. 7b is a cross-sectional view illustrating the state of a pouch-type all-solid-state battery according to one embodiment when pressurized.

[0027] FIG. 8a is an enlarged view of area M of FIG. 7a for explaining the first folding portion of a pouch outer material according to one embodiment.

[0028] FIG. 8b is an enlarged view of the M' area of ​​FIG. 7b to explain the first folding portion of the pouch outer material according to one embodiment.

[0029] FIG. 8c is a modified embodiment of FIG. 8a for explaining an adhesive member according to one embodiment.

[0030] FIG. 8d is a drawing for illustrating an adhesive member according to another embodiment. That is, it is a modified embodiment of FIG. 8c.

[0031] FIGS. 9 and FIGS. 10 are drawings for explaining a modified embodiment of the first folding part of FIG. 8a.

[0032]

[0033] 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.

[0034] 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.

[0035] 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.

[0036] The embodiments described herein will be described with reference to cross-sectional and / or plan views, which are exemplary illustrations of the invention. In the drawings, the thicknesses of films and regions are exaggerated for effective description 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. Although terms such as first, second, third, etc., have been used to describe various components in the various embodiments of this specification, 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.

[0037] 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.

[0038] In this specification, each of the phrases such as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof.

[0039]

[0040] All-solid-state battery

[0041] FIG. 1 is a cross-sectional view illustrating an all-solid-state battery according to embodiments of the present invention.

[0042] Referring to FIG. 1, the all-solid-state battery (10) may include a positive electrode layer (100), a negative electrode layer (200) facing the positive electrode layer (100), and a solid electrolyte layer (300) disposed between the positive electrode layer (100) and the negative electrode layer (200). However, not limited thereto, the all-solid-state battery (10) may further include an additional functional layer, such as an adhesion-enhancing layer, disposed 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).

[0043] The positive layer (100) may include a positive current collector (110) and a positive active material layer (120) disposed on the positive current collector (110). The positive active material layer (120) may include a positive active material, a solid electrolyte, a conductive material, and a binder.

[0044] The positive current collector (110) can provide a reference surface on which the positive active material layer (120) is placed. The positive current collector (110) may have a plate or foil form. For example, the positive current collector (110) may include indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), or an alloy thereof.

[0045] Unlike as illustrated in FIG. 1, in one embodiment of the present invention, the positive current collector (110) may be omitted. Although not illustrated, a carbon layer with a thickness of 0.1 μm to 4 μm may be further disposed between the positive current collector (110) and the positive active material layer (120) to increase the bonding strength between the positive current collector (110) and the positive active material layer (120).

[0046] The positive electrode active material may be a material capable of reversibly absorbing and desorbing lithium ions. For example, the positive electrode active material may include 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, but is not limited thereto. The positive electrode active material may be a single material or a mixture of two or more materials.

[0047] Lithium transition metal oxides are, for example, Li a A 1-b B b D2(0.90≤a≤1, 0≤b≤0.5), Li a E 1-b B b O 2-c D c (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05), LiE 2-b B b O 4-c D c (0≤b≤0.5, 0≤c≤0.05), Li a Ni 1-b-c Co b B c D α(0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Nor 1-b-c Co b B c O 2-α F α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Nor 1-b-c Mn b B c D α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α≤2), Li a Nor 1-b-c Mn b B c O 2-α F α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Nor b E c G d O2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0.001≤d≤0.1), Li a Nor b Co c Mn d GeO2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0.001≤e≤0.1), Li a NiG b O2(0.9≤a≤1, 0.001≤b≤0.1), Li a CoG b O2(0.90≤a≤1, 0.001≤b≤0.1), Li a MnG b O2(0.90≤a≤1, 0.001≤b≤0.1), Li a Mn2GbO4(0.90≤a≤1, 0.001≤b≤0.1), QO2, QS2, LiQS2, V2O5, LiV2O5, LiIO2, LiNiVO4, Li 3-f J2(PO4)3(0≤f≤2), Li 3-fIt may be a compound represented by any one of Fe2(PO4)3 (0≤f≤2) or LiFePO4. In such a compound, the uppercase "A" is Ni, Co, Mn, or a combination thereof; the uppercase "B" is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof; the uppercase "D" is O, F, S, P, or a combination thereof; the uppercase "E" is Co, Mn, or a combination thereof; the uppercase "F" is F, S, P, or a combination thereof; the uppercase "G" is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; the uppercase "Q" is Ti, Mo, Mn, or a combination thereof; the uppercase "I" is Cr, V, Fe, Sc, Y, or a combination thereof; and the uppercase "J" is V, Cr, Mn, Co, Ni, Cu, or a combination thereof.

[0048] 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 described above. The "layered rock salt type structure" is, for example, a cubic rock salt type structure. <111> It is a structure in which oxygen and metal atomic layers are alternately and regularly arranged in a specific direction, thereby forming a two-dimensional plane for each atomic layer. The "cubic rock salt type structure" represents a sodium chloride (NaCl) type structure, which is a type of crystal structure; specifically, it exhibits a structure in which face-centered cubic lattices (fcc) formed by cations and anions, respectively, are offset from each other by half the ridge of the unit lattice. Lithium transition metal oxides having such a layered rock salt type structure are, for example, LiNi x Co y Al z O2(NCA) or LiNi x Co y Mnz O2(NCM) (0 <x<1,0<y<1, 0<z<1, x+y+z=1) 등의 삼원계 리튬전이금속산화물일 수 있다. 양극 활물질이 층상암염형 구조를 갖는 삼원계 리튬전이금속산화물을 포함하는 경우, 전고체 전지(10)의 에너지 밀도가 커지고 열안정성이 향상될 수 있다.

[0049] The aforementioned compound contained in the positive electrode active material may be covered by a coating layer (not shown). The positive electrode active material may also be a mixture of the aforementioned compound and the compound to which the coating layer is added. Meanwhile, the coating layer added to the surface of the positive electrode active material may include, for example, oxides, hydroxides, oxyhydroxides, oxycarbonates, or hydroxycarbonates of the following coating elements. The compounds forming this coating layer may be amorphous or crystalline. The coating elements included in the coating layer may include Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof. The coating layer may include, for example, Li2O-ZrO2 (LZO). The method for forming the coating layer may be selected within a range that does not adversely affect the physical properties of the positive electrode active material. The method for forming the coating layer may include, for example, spray coating or immersion methods.

[0050] When the positive electrode active material is a ternary lithium transition metal oxide such as NCA or NCM and contains nickel (Ni), the capacity density of the all-solid-state battery (10) can be increased, and the metal leaching of the positive electrode active material in the charged state can be reduced. As a result, the cycle characteristics of the all-solid-state battery (10) in the charged state can be improved. Meanwhile, “cycle characteristics” is a characteristic that indicates the degree of deterioration of the all-solid-state battery (10) due to charging and discharging of the all-solid-state battery (10). An all-solid-state battery (10) with high cycle characteristics has a small degree of deterioration due to charging and discharging, while an all-solid-state battery (10) with low cycle characteristics may have a large degree of deterioration due to charging and discharging.

[0051] The shape of the positive electrode active material may include particle shapes such as spheres or ellipsoids. The particle size and content of the positive electrode active material are not particularly limited.

[0052] The solid electrolyte may include a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. Sulfide-based solid electrolytes 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 (m, n are positive numbers, uppercase “Z” is one of Ge, Zn, or Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li p MO q (p, q are positive numbers, uppercase “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 It may include at least one selected from (0≤x≤2).

[0053] Sulfide-based solid electrolytes are, for example, 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 It may be an argyrodite-type compound comprising one or more selected from (0≤x≤2). In particular, the sulfide-based solid electrolyte may be an argyrodite-type compound comprising one or more selected from Li6PS5Cl, Li6PS5Br, and Li6PS5I. The density of the argyrodite-type solid electrolyte may be 1.5 g / cc to 2.0 g / cc. By having a density of 1.5 g / cc or higher for the argyrodite-type solid electrolyte, the internal resistance of the all-solid-state battery is reduced, and defects such as penetration and short circuit of the solid electrolyte film due to lithium dendrite formation can be prevented. The elastic modulus of the solid electrolyte may be, for example, 15 GPa to 35 GPa.

[0054] The solid electrolyte included in the positive electrode active material layer (120) may have a smaller average particle size (D50) compared to the solid electrolyte included in the solid electrolyte layer (300). For example, the average particle size (D50) of the solid electrolyte included in the positive electrode active material layer (120) may be 90% or less, 80% or less, 70% or less, 60% or less, 50% or less, 40% or less, 30% or less, or 20% or less of the average particle size (D50) of the solid electrolyte included in the solid electrolyte layer (300). Meanwhile, the average particle size (D50) may be a median diameter measured using a laser particle size distribution meter.

[0055] The positive active material layer (120) may include a conductive material. The conductive material may have conductivity without causing chemical changes in the all-solid-state battery (10), thereby increasing the conductivity of the positive active material and the solid electrolyte. The conductive material may include a carbon-based material. The conductive material may include, for example, one or more selected from graphite, carbon black, acetylene black, carbon nanofibers, and carbon nanotubes.

[0056] The positive active material layer (120) may further include a binder. The binder may include a material for bonding the positive active material, solid electrolyte, and conductive material included in the positive active material layer (120), and for improving the bonding strength with the positive current collector (110). For example, the binder may include polyvinylidene fluoride, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, or polymethyl methacrylate.

[0057] When the total of the positive active material, solid electrolyte, conductive material, and binder is 100 parts by weight, the positive active material layer (120) may include 85 to 92 parts by weight of the positive active material. The positive active material layer (120) may include 0.5 to 1.5 parts by weight of the binder.

[0058] In the positive electrode active material layer (120), the conductive material may have 1 to 50 parts by weight per 100 parts by weight of solid electrolyte. If the conductive material is less than 1 part by weight per 100 parts by weight of solid electrolyte, the electrical conductivity of the positive electrode active material layer (120) may be reduced. If the conductive material is more than 50 parts by weight per 100 parts by weight of solid electrolyte, the ratio of the conductive material is excessively high, so a coating layer covering the surface of the solid electrolyte may not be properly formed.

[0059] According to the embodiments, the positive active material layer (120) may further include at least one additive selected from the group consisting of a filler, a coating agent, a dispersant, and an ion-conducting aid, in addition to the positive active material, solid electrolyte, conductive material, and binder described above.

[0060] The solid electrolyte layer (300) is disposed between the positive electrode layer (100) and the negative electrode layer (200) and may include a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. The solid electrolyte included in the solid electrolyte layer (300) may be the same as or different from any one of the materials that may be included in the solid electrolyte included in the aforementioned positive electrode active material layer (120).

[0061] The solid electrolyte layer (300) may further include a binder. The binder in the solid electrolyte layer (300) is not limited to, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc. The binder of the solid electrolyte layer (300) may be the same as or different from the binder included in the positive active material layer (120) or the binder included in the coating layer (220).

[0062] The negative electrode layer (200) may include a negative electrode current collector (210) and a coating layer (220) on the negative electrode current collector (210). The negative electrode current collector (210) may provide a reference surface on which the coating layer (220) is placed. The negative electrode current collector (210) may include, for example, a material that does not react with lithium, that is, does not form any alloys or compounds with lithium. For example, the negative electrode current collector (210) may include at least one metal selected from the group consisting 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 1 μm to 20 μm, more specifically 5 μm to 15 μm, and more specifically 7 μm to 10 μm.

[0063] The negative current collector (210) may be composed of one of the metals described above, or may include an alloy of two or more metals or a coating material. The negative current collector (210) may, for example, have a plate-like or foil-like shape. Meanwhile, in one embodiment, the negative current collector (210) may be omitted.

[0064] The coating layer (220) can allow lithium metal to grow between the all-solid-state battery (10) and the negative current collector (210) during charging. The coating layer (220) can serve as a protective layer for the lithium metal and simultaneously suppress the precipitation and growth of lithium dendrites.

[0065] The coating layer (220) may include metal and carbon. For example, the coating layer (220) may include at least one metal selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn). The coating layer (220) may include at least one carbon selected from the group consisting of carbon black, acetylene black, furnace black, ketjen black, and graphene. In one embodiment, the coating layer (220) may include a mixture of carbon black and silver (Ag).

[0066] The coating layer (220) may further include other additives in addition to metal and carbon. The coating layer (220) may further include at least one additive selected from the group consisting of, for example, binders, fillers, coating agents, dispersants, and ion-conducting aids.

[0067] The coating layer (220) may have a smaller thickness compared to the positive active material layer (120). The thickness of the coating layer (220) may be, for example, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, or 5% or less of the thickness of the positive active material layer (120). The thickness of the coating layer (220) may be, for example, 1 µm to 20 µm, 2 µm to 10 µm, or 3 µm to 7 µm. If the thickness of the coating layer (220) is excessively thin, lithium dendrites formed between the coating layer (220) and the negative current collector (210) may cause the coating layer (220) to collapse, thereby degrading the cycle characteristics of the all-solid-state battery (10). If the thickness of the coating layer (220) increases excessively, the energy density of the all-solid-state battery (10) decreases and the internal resistance of the all-solid-state battery (10) due to the coating layer (220) increases, which may degrade the cycle characteristics of the all-solid-state battery (10).

[0068] Meanwhile, although not shown, a carbon layer may be further included to improve adhesion between the coating layer (220) and the solid electrolyte layer (300).

[0069] In one embodiment, the solid electrolyte layer (300) may include an anode solid electrolyte layer (310) and a cathode solid electrolyte layer (320). The anode solid electrolyte layer (310) may be adjacent to the anode layer (100), and the cathode solid electrolyte layer (320) may be adjacent to the cathode layer (200). Each of the anode solid electrolyte layer (310) and the cathode solid electrolyte layer (320) may include the solid electrolyte described above.

[0070] FIG. 2a is a diagram showing the state of accommodating an electrode assembly within a pouch according to one embodiment of the present invention. FIG. 2b is a diagram schematically illustrating a cross-section of a pouch-type all-solid-state battery.

[0071] Referring to FIGS. 2a and 2b, a pouch-type all-solid-state battery (PCL) may include a pouch outer casing (PCH) and an electrode assembly (ESA) in which at least one unit cell is stacked. The electrode assembly (ESA) may be received in a receiving portion (REP) of the pouch outer casing (PCH).

[0072] In this specification, the term "unit cell" may refer to a basic unit comprising components that constitute a cell. For example, a unit cell may include a first electrode, a second electrode having opposite polarity to the first electrode, and a solid electrolyte layer between the first and second electrodes. The first electrode may include a first electrode current collector (PLT1) and a first electrode coating layer and / or a first electrode active material layer formed on the first electrode current collector (PLT1), and the second electrode may include a second electrode current collector (PLT2) and a second electrode coating layer and / or a second electrode active material layer formed on the second electrode current collector (PLT2).

[0073] In one embodiment, the unit cell may include a positive electrode layer (100), a negative electrode layer (200), and a solid electrolyte layer (300) between the positive electrode layer (100) and the negative electrode layer (200). Here, the positive electrode layer (100), the negative electrode layer (200), and the solid electrolyte layer (300) may be identical to the configuration of the all-solid-state battery (10) described in FIG. 1. Also, in one embodiment, the first electrode current collector (PLT1) may be a positive electrode current collector (110) and the second electrode current collector (PLT2) may be a negative electrode current collector (200), or they may be opposite to each other.

[0074] The electrode assembly (ESA) may include a unit cell and a substrate tab (TB) electrically connected to the unit cell. In one embodiment, the substrate tab (TB) may be electrically connected to an electrode current collector and may protrude from the electrode current collector. For example, a first substrate tab (TB1) may be electrically connected to a first electrode current collector (PLT1), and a second substrate tab (TB2) may be electrically connected to a second electrode current collector (PLT2).

[0075] A pouch-type all-solid-state battery (PCL) may include a lead tab (LTB) connected to a substrate tab (TB). The lead tab (LTB) may be electrically connected to the substrate tab (TB) and protrude outside the pouch outer casing (PCH). In other words, the lead tab (LTB) may be configured so that the electrode assembly (ESA) is electrically connected to the outside of the pouch outer casing (PCH). The method of electrical connection is not particularly limited, and methods such as welding, soldering, or brazing may be used.

[0076] The electrode assembly (ESA) may further include at least one elastic pad (ELM). The elastic pad (ELM) may be disposed between unit cells. Additionally, the elastic pad (ELM) may be disposed on the top surface and the bottom surface, respectively, of the electrode assembly (ESA).

[0077] The elastic pad (ELM) can facilitate good contact between solid components to ensure uniform pressure distribution within the electrode assembly (ESA), and also serve to relieve stress transmitted to the solid electrolyte. Additionally, the elastic pad (ELM) can prevent cracks from forming in the solid electrolyte caused by stress accumulation due to changes in the thickness of the unit cell during charging and discharging.

[0078] The material of the elastic pad (ELM) is not particularly limited as long as it is a material capable of shrinking and expanding in response to changes in the thickness of the unit cell. In one embodiment, the elastic pad (ELM) may include an acrylic resin, a urethane resin, a silicone resin, or a combination thereof.

[0079] In one embodiment, the elastic pad (ELM) may have a single layer or a multilayer structure.

[0080] In one embodiment, the pouch outer material (PCH) may be formed such that a first outer material (POH1) and a second outer material (POH2) are arranged to face each other. The first outer edge (EDG1) of the first outer material (POH1) and the second outer edge (EDG2) of the second outer material (POH2) may be in contact and sealed to form first and second wing portions (SID1, SID2), a front sealing portion (FSD), and a rear sealing portion (RSD).

[0081]

[0082] FIGS. 3a and 3b are cross-sectional views illustrating problems that occur when a pouch-type all-solid-state battery is driven under pressure according to comparative examples.

[0083] Referring to FIG. 3a, the wing portion of the pouch-type solid-state battery can be folded to form a folding portion (FDP). Meanwhile, the pouch-type solid-state battery can be operated stably under a predetermined pressure. For example, when the pouch-type solid-state battery is pressurized by a pressurizing jig (PRJ), the pouch-type solid-state battery may be compressed and its thickness reduced. At this time, if the length of the folding portion (FDP) is greater than the reduced thickness of the battery, the folding portion (FDP) may come into contact with the pressurizing jig (PRJ) and hinder the pressurization of the pressurizing jig. As a result, the desired pressure may not be applied to the electrode assembly (ESA), or uneven pressure transmission may occur. In other words, the folding portion (FDP) may become an obstacle to the pressurized operation of the pouch-type solid-state battery.

[0084] Referring to FIG. 3b, the wing portion of the pouch-type solid-state battery can be folded to form a folding portion (FDP). Meanwhile, the pouch-type solid-state battery can be operated stably under a predetermined pressure. For example, when the pouch-type solid-state battery is pressurized by a pressurizing jig (PRJ), the pouch-type solid-state battery may be compressed and its thickness reduced. At this time, if the uppermost portion of the adhesive member (ADM) protrudes higher than the compressed battery, the adhesive member (ADM) may come into contact with the pressurizing jig (PRJ) and hinder the pressurization of the pressurizing jig. As a result, the desired pressure may not be applied to the electrode assembly (ESA), or uneven pressure transmission may occur. In other words, the adhesive member (ADM) may become an obstacle to the pressurized operation of the pouch-type solid-state battery.

[0085]

[0086] Hereinafter, with reference to FIGS. 4 to 10, a method for manufacturing an all-solid-state battery capable of preventing interference of the folding part when the pouch-type all-solid-state battery is driven by pressure, and an all-solid-state battery manufactured through the same will be described.

[0087]

[0088] Method for manufacturing a pouch-type all-solid-state battery

[0089] FIG. 4 is a flowchart for explaining a method for manufacturing a pouch-type all-solid-state battery according to an embodiment of the present invention. Referring to FIG. 4, the method for manufacturing a pouch-type all-solid-state battery (S10) may include sealing a pouch outer material containing an electrode assembly (S100); cutting between a gas pocket and a receiving portion of the pouch outer material (S200); and folding a wing portion of the pouch outer material (S300). The method for manufacturing a all-solid-state battery (S10) may further include fixing the folding portion (S400). The manufactured pouch-type all-solid-state battery may be operated under a state where it is pressurized by a driving pressure.

[0090] Hereinafter, each of the steps described above will be explained in detail with reference to FIGS. 2a and FIGS. 5a to 5e. FIG. 5a is a plan view of a pouch outer material (PCH) accommodating an electrode assembly according to one embodiment. FIG. 5b is a cross-sectional view of a pouch outer material (PCH) accommodating an electrode assembly according to one embodiment.

[0091] Referring to FIG. 2a, an electrode assembly (ESA) is accommodated in a pouch outer material (PCH), and a pouch-type all-solid-state battery can be formed.

[0092] Referring to FIGS. 5a and 5b, the pouch outer material (PCH) may include a pouch body (PCB), a receiving portion (REP), and a gas pocket (GSP).

[0093] The pouch body (PCB) can form the overall shape of the pouch (200). In an embodiment of the present invention, the pouch (200) may have a rectangular shape, but is not necessarily limited thereto.

[0094] A receiving portion (REP) may be formed in a pouch body (PCB). As disclosed in FIG. 2a, an electrode assembly (ESA) may be received inside the receiving portion (REP). In an embodiment of the present invention, the receiving portion (REP) may be in a rectangular shape or a rectangular shape with four rounded corners, but is not necessarily limited thereto. The shape of the receiving portion (REP) may be changed to correspond to the shape of the electrode assembly (ESA).

[0095] A gas pocket (GSP) can be formed on a pouch body (PCB) spaced apart from a receiving portion (REP). During the pressurized sealing process, gas (GAS) in the receiving portion (REP) can move to the gas pocket (GSP).

[0096] Referring again to FIG. 2a, the pouch body (PCB) may be in the form where the first outer material (POH1) and the second outer material (POH2) are overlapped.

[0097] In one embodiment, the first exterior material (POH1) may have, for example, a single-layer structure or a multi-layer structure. The multi-layer structure may have, for example, a 2-layer structure to a 50-layer structure. The multi-layer structure may have, for example, a 2-layer structure, a 3-layer structure, a 4-layer structure, a 5-layer structure, a 6-layer structure, etc. The multi-layer structure may include one or more buffer layers. The multi-layer structure may include, for example, one or more metal layers and / or one or more polymer layers. The multi-layer structure may have, for example, a polymer layer / buffer layer structure, a polymer layer / metal layer / buffer layer structure, a metal layer / buffer layer structure, a polymer layer / buffer layer / polymer layer structure, etc. The multi-layer structure may have, for example, a polymer layer / first buffer layer / polymer layer / second buffer layer structure. The buffer layer included in the first exterior material (POH1) may be, for example, a porous layer. The porous layer may be, for example, a layer containing hollow particles or a layer in which pores have been introduced. The first outer layer (POH1) may include layers having opposite properties to balance the properties within the range of providing moisture and gas performance and buffering performance required by the electrode assembly (ESA).

[0098] The second exterior material (POH2) may include one or more selected from a buffer layer, a metal layer, and a polymer layer. The second exterior material (POH2) may have the same structure, thickness, physical properties, etc. as the first exterior material (POH1). The specific details of the second exterior material (61) may include the details of the first exterior material (POH1) described above. The second exterior material (POH2) may not include a buffer layer.

[0099] At least one of the first exterior material (POH1) and the second exterior material (POH2) may include a receiving portion (REP).

[0100] For example, the first outer material (POH1) may include a first receiving portion (REP1), and the second outer material (POH2) may include a second receiving portion (REP2). The first receiving portion (REP1) may receive a part of the electrode assembly (ESA), and the second receiving portion (REP2) may receive the remaining part of the electrode assembly (ESA). The first receiving portion (REP1) and the second receiving portion (REP2) may be connected to form a receiving portion (REP) of the pouch outer material (PCH).

[0101] At least one of the first exterior material (POH1) and the second exterior material (POH2) may include a gas pocket (GSP).

[0102] For example, referring to FIG. 5b, the first outer material (POH1) may include a first gas pocket (GSP1). The second outer material (POH2) may include a second gas pocket (GSP2). The first gas pocket (GSP1) and the second gas pocket (GSP2) may be connected to form a gas pocket (GSP) of the pouch outer material (PCH).

[0103] Before the pressure sealing process is performed, there is a small space between the first outer layer (POH1) and the second outer layer (POH2), so that the receiving portion (REP) and the gas pocket (GSP) can be connected.

[0104] Referring to FIG. 5b, the gas in the receiving portion (REP) can move to the gas pocket (GSP) through the communication space (COS) formed between the two layers of the pouch body (PCB). When all the gas in the receiving portion (REP) has moved to the gas pocket (GSP), the interior of the receiving portion (REP) can form a vacuum state, excluding the electrode assembly (ESA).

[0105] Referring again to FIG. 5a, the pouch outer material (PCH) may include first to fourth sides (SDE1-SDE4).

[0106] Referring to FIGS. 4, 5a, and 5c, in one embodiment, a method for manufacturing a pouch-type all-solid-state battery may include sealing (S100) a pouch outer material containing an electrode assembly, which may include first to fourth sides (SDE4) of the pouch outer material (PCH); and sealing between a receiving portion (REP) and a gas pocket (GSP). In one embodiment, the sealing may be performed by a thermal fusion method.

[0107] In one embodiment, sealing the pouch outer material (PCH) (S100) can be performed while applying pressure to the receiving portion (REP). As a result, the electrode assembly (ESA) can be compressed.

[0108] In one embodiment, the receiving portion (REP) may be pressurized by a sealing pressure (SP). The sealing pressure (SP) may be 0.5 MPa to 3 MPa, and specifically 0.5 MPa to 1 MPa.

[0109] Referring again to FIG. 5a and FIG. 5c, in one embodiment, the first side (SDE1) may be defined as an edge region adjacent to the receiving portion (REP) on the pouch body (PCB). The first side (SDE1) of the pouch outer material (PCH) may be sealed along the second direction (D2) to form a temporary sealing portion (PSD; see FIG. 5c). The temporary sealing portion (PSD) may then be removed together with the gas pocket (GSP) by cutting between the receiving portion (REP) and the gas pocket (GSP).

[0110] In one embodiment, the second side (SDE2) may be defined as an edge region adjacent to the gas pocket (GSP) on the pouch body (PCB). The second side (SDE2) of the pouch outer material (PCH) may be sealed along the second direction (D2) to form a second wing portion (SID2; see FIG. 5c).

[0111] In one embodiment, the third side (SDE3) may be defined as an edge region adjacent to the first lead tab (LTB1) on the pouch body (PCB). The third side (SDE3) of the pouch outer material (PCH) may be sealed along the first direction (D1) to form a front sealing portion (FSD; see FIG. 5c).

[0112] In one embodiment, the fourth side (SDE4) may be defined as an edge region adjacent to the second lead tab (LTB2) on the pouch body (PCB). The fourth side (SDE4) of the pouch outer material (PCH) may be sealed along the first direction (D1) to form a rear sealing portion (RSD; see FIG. 5c).

[0113] In one embodiment, the pouch outer material (PCH) may further include an inner sealing portion (ISD). The space between the receiving portion (REP) and the gas pocket (GSP) on the pouch body (PCB) may be sealed to form an inner sealing portion (ISD). Subsequently, the inner sealing portion (ISD) may be cut along a second direction (D2) to form a first wing portion (SID1; see FIG. 5d).

[0114] Referring to FIGS. 4, 5c, and 5d, a method for manufacturing a pouch-type all-solid-state battery may include cutting between a gas pocket and a receiving portion of a pouch outer material (S200). Specifically, the space between a receiving portion (REP) and a gas pocket (GSP) of a pouch outer material (PCH) may be cut along a second direction (D2). A first wing portion (SID1) may be formed by cutting between a receiving portion (REP) and a gas pocket (GSP) of a pouch outer material (PCH).

[0115] In one embodiment, cutting (S200) between the receiving portion (REP) and the gas pocket (GSP) of the pouch outer material (PCH) may involve cutting a portion of the inner sealing portion (ISD) along the second direction (D2). For example, it may involve cutting along the first cutting line (CR1) or the second cutting line (CR2) indicated by the dashed line in FIG. 5c.

[0116] As a result, the gas pocket (GSP) can be removed, and a portion of the inner sealing portion (ISD) can be removed together. By removing a portion of the inner sealing portion (ISD), a first wing portion (SID1) can be formed in which the width of the inner sealing portion (ISD) in the first direction (D1) is slightly reduced.

[0117] Referring to FIG. 5d and FIG. 5e, in one embodiment, the pouch outer material (PCH) may further include an unsealed portion (USP), which is an unsealed area formed inside the first wing portion (SID1), the second wing portion (SID2), the front sealing portion (FSD), and the rear sealing portion (RSD).

[0118] Referring to FIGS. 4, 5d and 5e, a method for manufacturing a pouch-type all-solid-state battery may include folding the wing portion of the pouch outer material (S300).

[0119] In one embodiment, folding the wing portion of the pouch outer material (S300) may include folding the first wing portion (SID1) of the pouch outer material (PCH). The first wing portion (SID1) may be folded toward the first outer material area. At this time, at least a portion of the first wing portion (SID1) may be folded to form a first folding portion (FDP1; see FIG. 8a). The first folding portion (FDP1) may protrude in a third direction (D3).

[0120] In one embodiment, the first outer material region may be defined as the region where the first outer material (POH1) surrounds the upper region of the electrode assembly.

[0121] Folding the wing portion of the pouch outer material (PCH) (S300) may further include folding the second wing portion (SID2) of the pouch outer material (PCH). The second wing portion (SID2) may be folded toward the first outer material area. At this time, at least a portion of the second wing portion (SID2) may be folded to form a second folding portion. The second folding portion may protrude in a third direction (D3).

[0122] The wing portions may be folded such that the folding length TL in the third direction (D3) of each of the first and second folding portions (FDP1, FDP2) has a predetermined value. As described below with reference to FIG. 8a, TL may be greater than 3 mm, and specifically may be 4 mm to 50 mm, 4 mm to 40 mm, or 5 mm to 40 mm.

[0123] The method for manufacturing a pouch-type all-solid-state battery (S10) may include fixing the folding part (S400).

[0124] In one embodiment, fixing the folding portion (S400) may include fixing at least one of the first and second folding portions (FDP1, FDP2) with a fixing member (TPE; see FIG. 7a). In one embodiment, the fixing member (TPE) may be an adhesive tape.

[0125] For example, one end of the fixing member (TPE) may be attached to the first folding part (FDP1) and the other end may be attached to the first exterior material (POH1) to fix the first folding part (FDP1). For example, the other end of the fixing member (TPE) may be attached to the outer surface of the first receiving part (REP1) to fix the first folding part (FDP1).

[0126] A pouch-type all-solid-state battery (PCL) manufactured according to one embodiment can be driven by applying a driving pressure (DP) to the receiving portion (REP) of the pouch outer material (PCH). As described below with reference to FIG. 8a, the driving pressure (DP) may be 1 MPa to 5 MPa, and specifically 2 MPa to 2.5 MPa. The driving pressure (DP) may be smaller than the sealing pressure (SP) described above.

[0127] In another embodiment, fixing the folding part (S400) may be fixing at least one of the first and second folding parts (FDP1, FDP2) with an adhesive member (ADM; see FIG. 8c).

[0128] The adhesive member (ADM) can be attached between the first folding portion (FDP1) and the first exterior material area. For example, the first folding portion (FDP1) can be fixed by attaching one end of the adhesive member (ADM) to the first folding portion (FDP1) and attaching the other end to the first exterior material area.

[0129] In one embodiment, the adhesive member (ADM) can be positioned such that the first height (H1), which is the uppermost portion of the adhesive member (ADM) in the third direction (D3), is smaller than the second height (H2), which is the straight distance in the third direction from the bottom surface (or lowest point MIH; see FIG. 8d) of the adhesive member (ADM) to the upper surface (CTS) of the pouch-type all-solid-state battery. That is, the adhesive member (ADM) can be positioned such that the uppermost portion of the adhesive member (ADM) does not protrude higher than the upper surface (CTS) of the pouch-type all-solid-state battery.

[0130] Specifically, the adhesive member (ADM) can be positioned such that the second height (H2) is at least 1 mm larger than the first height (H1). That is, the adhesive member (ADM) can be positioned such that the highest point (MAH; see FIG. 8d) of the adhesive member (ADM) in the third direction (D3) is at least 1 mm lower than the top surface (CTS) of the pouch-type all-solid-state battery. By doing so, interference of the adhesive member (ADM) can be prevented during pressurized driving.

[0131] In one embodiment, the second height (H2) may be measured when the pouch-type all-solid-state battery (PCL) is pressurized with a driving pressure (DP) described below.

[0132] In one embodiment, the second height (H2) may be measured in the maximum discharge state of the pouch-type all-solid-state battery (PCL). The maximum discharge state may be a state where the SOC is about 1% or less, and specifically, a state where the SOC is 0%.

[0133] A pouch-type all-solid-state battery (PCL) manufactured according to one embodiment can be driven by applying a driving pressure (DP) to the receiving portion (REP) of the pouch outer material (PCH). As described below with reference to FIG. 8a, the driving pressure (DP) may be 1 MPa to 5 MPa, and specifically 2 MPa to 2.5 MPa. The driving pressure (DP) may be smaller than the sealing pressure (SP) described above.

[0134]

[0135] FIGS. 6a to 6d are plan views illustrating a method for manufacturing a pouch-type all-solid-state battery according to another embodiment. Detailed descriptions of technical features that overlap with those described with reference to FIGS. 5a to 5e are omitted, and the differences are described in detail.

[0136] Referring to FIG. 2a and FIG. 6a, in one embodiment, the pouch outer material (PCH) may include a first outer material (POH1) and a second outer material (POH2). One side of the first outer material (POH1) and the second outer material (POH2) may be connected. That is, the second side (SDE2) of the pouch outer material (PCH) may be connected. As a result, sealing is not required on the second side (SDE2), and a second wing portion, which is a sealing area, may not be formed on the second side (SDE2).

[0137] Referring to FIGS. 6a and 6b, sealing the pouch outer material containing the electrode assembly (S100) may include first, third, and fourth sides (SDE1, SDE3, SDE4) of the pouch outer material (PCH); and sealing the space between the receiving portion (REP) and the gas pocket (GSP).

[0138] Referring to FIG. 6b, as described above with reference to FIG. 5d, the first wing portion (SID1) can be formed by cutting along the second direction (D2) between the receiving portion (REP) and the gas pocket (GSP) of the pouch outer material (PCH).

[0139] Referring to FIG. 6c, folding the wing portion of the pouch outer material (S300) as described above with reference to FIG. 5e may include folding the first wing portion (SID1) of the pouch outer material (PCH). The first wing portion (SID1) may be folded toward the third direction (D3) or toward the pouch outer material (PCH). At this time, at least a portion of the first wing portion (SID1) may be folded to form a first folding portion (FDP1; see FIG. 8a).

[0140]

[0141] Pouch-type solid-state battery

[0142] FIG. 7a is a cross-sectional view illustrating a pouch-type all-solid-state battery according to one embodiment.

[0143] Referring to FIG. 2a, FIG. 5d, FIG. 5e and FIG. 7a, a pouch-type all-solid-state battery (PCL) according to one embodiment may include a pouch outer casing (PCH); and an electrode assembly (ESA) housed in the pouch outer casing (PCH).

[0144] With reference to FIG. 2a, the pouch outer material (PCH) can be configured to package an electrode assembly (ESA) by arranging the first outer material (POH1) and the second outer material (POH2), described above, to face each other. For example, the pouch outer material (PCH) may be formed by arranging the first outer material (POH1), which can accommodate at least a portion of the electrode assembly (ESA), and the second outer material (POH2), which can accommodate the remaining portion of the electrode assembly (ESA), to face each other. The first outer material (POH1) may surround a portion of the electrode assembly (ESA) to form a first outer material region (POR1) of the pouch-type all-solid-state battery, and the second outer material (POH2) may surround the remaining portion of the electrode assembly (ESA) to form a second outer material region (POR2) ​​of the pouch-type all-solid-state battery. For example, the first outer material (POH1) can surround the upper part of the electrode assembly (ESA) to form the first outer material region (POR1) of the pouch-type all-solid-state battery. The second outer material (POH2) can surround the lower part of the electrode assembly (ESA) to form the second outer material region (POR2) ​​of the pouch-type all-solid-state battery.

[0145] As another example, although not illustrated, the pouch outer material (PCH) may be formed by arranging a first outer material (POH1) capable of accommodating the entire electrode assembly (ESA) and a second outer material (POH2) capable of serving as a cover for the second outer material to face each other. That is, the first outer material (POH1) can form the first outer material region (POR1) of the pouch-type all-solid-state battery by wrapping the remaining surfaces of the electrode assembly, excluding the upper or lower surface.

[0146] Referring to FIGS. 2a, 5d, and 7a, the pouch outer material (PCH) may include a pouch body (PCB) and a receiving portion (REP) formed on the pouch body (PCB). Additionally, the pouch outer material (PCH) may include a sealing portion formed on the outer edge of the pouch body (PCB). The sealing portion may include a front sealing portion (FSD), a rear sealing portion (RSD), and a first wing portion (SID1). Referring to FIG. 5e, the sealing portion may further include a second wing portion (SID2).

[0147] Referring to FIG. 5e, in one embodiment, the first wing portion (SID1) and the second wing portion (SID2) may be spaced apart from each other in a first direction (D1). Each of the first and second wing portions (SID1, SID2) may extend in a second direction (D2). The second direction (D2) may intersect with the first direction (D1).

[0148] In one embodiment, the front sealing portion (FSD) and the rear sealing portion (RSD) may be spaced apart from each other in a second direction (D2). Each of the front sealing portion (FSD) and the rear sealing portion (RSD) may extend in a first direction (D1).

[0149] In one embodiment, the first and second wing portions (SID1, SID2) may each be located on the long axis portion of the pouch outer material (PCH). The front sealing portion (FSD) and the rear sealing portion (RSD) may each be located on the short axis portion of the pouch outer material (PCH).

[0150] In one embodiment, a pouch-type all-solid-state battery (PCL) may include a first lead tab (LTB1) and a second lead tab (LTB2). The first lead tab (LTB1) may be either a positive lead tab or a negative lead tab, and the second lead tab (LTB2) may be the other of a positive lead tab and a negative lead tab.

[0151] In one embodiment, the first lead tab (LTB1) may be adjacent to the front sealing portion (FSD). The second lead tab (LTB2) may be adjacent to the rear sealing portion (RSD). That is, each of the first lead tab (LTB1) and the second lead tab (LTB2) may be adjacent to the short portion of the pouch outer material (PCH).

[0152] In one embodiment, the first lead tab (LTB1) and the second lead tab (LTB2) can be aligned along the second direction (D2).

[0153] FIG. 8a is an enlarged view of the M area of ​​FIG. 7a to explain the first wing portion of the pouch outer material according to one embodiment.

[0154] Referring to FIG. 5e and FIG. 8a, the first wing portion (SID1) may include a first folding portion (FDP1) in which at least a portion of the first wing portion (SID1) is folded.

[0155] In one embodiment, the first wing portion (SID1) can be folded inward. Specifically, the first wing portion (SID1) can be folded into the first exterior material area (POR1). For example, the first folding portion (FDP1) can be folded in the third direction (D3). Alternatively, the first folding portion (FDP1) can be folded adjacent to the first exterior material area (POR1).

[0156] Referring to FIG. 8a, in one embodiment, the first folding part (FDP1) may have a length TL in the third direction (D3).

[0157] In one embodiment, the first exterior material area (POR1) may include a joint (TRP) connecting the first receiving portion (REP1) and the first wing portion (SID1).

[0158] Referring again to FIG. 8a, in one embodiment, the joint (TRP) may include a curved surface formed convexly on the inner part of the first receiving portion (REP1). By having such a curved surface, pressure can be prevented from concentrating on the joint (TRP) when the pouch-type all-solid-state battery (PCL) is pressurized and compressed.

[0159] A pouch-type solid-state battery (PCL) can be operated under a driving pressure (DP). That is, a pouch-type solid-state battery (PCL) can be charged and discharged under a driving pressure (DP). Through this, the performance of the battery can be improved by maintaining uniform contact between the electrode and the solid electrolyte layer and suppressing dendrite growth. For example, a pouch-type solid-state battery (PCL) can be pressurized to a driving pressure (DP) using a pressurizing jig (PRJ), and specifically, the electrode assembly (ESA) can be compressed by pressurizing the electrode assembly receiving portion of the pouch outer material (PCH) to a driving pressure (DP).

[0160] Referring again to FIG. 8a, before pressurization with driving pressure (DP), the first outer material region (POR1) of the pouch-type all-solid-state battery (PCL) may have a first thickness (TK1) in the third direction (D3). For example, the first thickness (TK1) may be a straight distance in the third direction (D3) from the lower surface of the first wing portion (SID1) to the upper surface of the first outer material region (POR1).

[0161] In one embodiment, the first thickness (TK1) may be 7 mm to 50 mm.

[0162] In one embodiment, the first thickness (TK1) may be the thickness of the pouch-type all-solid-state battery (PCL) at the maximum discharge state. The maximum discharge state may be a state where the SOC is about 1% or less, and specifically, a state where the SOC is 0%. As an example, the first thickness (TK1) may be measured before the pouch-type all-solid-state battery (PCL) is first charged.

[0163] In one embodiment, the first thickness (TK1) can be estimated from a value measured before pressurizing a pouch-type solid-state battery having the same configuration as the pouch-type solid-state battery of the present invention with a driving pressure (DP). For example, the value measured by the above method before pressurizing and compressing a pouch-type solid-state battery having the same configuration as the battery of the present invention with a driving pressure (DP) can be defined as the first thickness (TK1). For example, the first thickness (TK1) may be measured before the solid-state battery is first charged.

[0164] FIG. 7b is a cross-sectional view illustrating the state of a pouch-type all-solid-state battery according to one embodiment when pressurized. FIG. 8b is an enlarged view of the M' area of ​​FIG. 7b illustrating the first folding portion of the pouch outer material according to one embodiment. Referring to FIG. 7b, when pressurized by a driving pressure (DP), the pouch-type all-solid-state battery (PCL) can be compressed.

[0165] Referring to FIG. 8b, in one embodiment, when pressurized by a driving pressure (DP), the first outer material region (POR1) of the pouch-type all-solid-state battery (PCL) may have a driving thickness (PT) in the third direction (D3). For example, the driving thickness (PT) may be a straight distance in the third direction (D3) from the lower surface of the first wing portion (SID1) to the upper surface of the first outer material region (POR1).

[0166] In one embodiment, the driving thickness (PT) may vary depending on the discharge state of the pouch-type all-solid-state battery (PCL). Specifically, the driving thickness (PT) may increase as the State of Charge (SOC, %) value increases.

[0167] In one embodiment, the minimum driving thickness may be defined as the minimum thickness of the first outer material region (POR1). For example, the minimum driving thickness may be the driving thickness (PT) at the maximum discharge state of the pouch-type all-solid-state battery (PCL). The maximum discharge state may be a state where the SOC is about 1% or less, and specifically, a state where the SOC is 0%. At the maximum discharge state, the first outer material region (POR1) of the pouch-type all-solid-state battery (PCL) may have a minimum driving thickness.

[0168] In one embodiment, the minimum driving thickness can be estimated from a value measured after compressing a pouch-type solid-state battery with the same configuration as the pouch-type solid-state battery (PCL) of the present invention by applying a driving pressure (DP).

[0169] In one embodiment, the minimum driving thickness may be measured by applying a driving pressure (DP) before the pouch-type all-solid-state battery of the present invention is first charged.

[0170] In one embodiment, the minimum driving thickness may be smaller than the first thickness (TK1). In one embodiment, the first folding part (FDP1) may have a length TL in the third direction (D3).

[0171] In one embodiment, the length (TL) of the first folding portion (FDP1) in the third direction (D3) may be smaller than the minimum driving thickness. This prevents the first folding portion (FDP1) from interfering with the pressurization, and consequently, the electrode assembly within the pouch-type all-solid-state battery (PCL) can be pressurized to a desired pressure.

[0172] Referring again to FIGS. 7a and FIGS. 8a, for example, the first folding part (FDP1) can be folded parallel to the third direction (D3).

[0173] In one embodiment, the ratio of the length (TL) of the first folding portion (FDP1) in the third direction (D3) to the first thickness (TK1) may be 1 or less. Specifically, the ratio (TL / TK1) of the length (TL) of the first folding portion (FDP1) in the third direction (D3) to the first thickness (TK1) may be 0.4 to 0.8. By having the above ratio range, interference of the first folding portion (FDP1) can be prevented during pressurized operation of the pouch-type all-solid-state battery (PCL). Specifically, if the above ratio (TL / TK1) range is exceeded, the first folding portion (FDP1) may be damaged by the pressurized jig. In addition, due to interference of the first folding portion (FDP1), appropriate pressure may not be applied to the electrode assembly inside the pouch (PCH), and as a result, cell performance may be degraded. If the ratio (TL / TK1) is less than the above range, it is difficult to secure sufficient tensile strength, and the first wing portion (sealed portion) may have difficulty withstanding the internal pressure generated during pressurized operation. In other words, there is a high risk that the pouch will be damaged and the performance of the electrode assembly will be degraded. By having the above ratio range, it is possible to prevent the first folding portion (FDP1) from interfering with the pressurization when the all-solid-state battery is pressurized (charged / discharged), and as a result, the electrode assembly inside the pouch can be pressurized to the desired pressure.

[0174] For example, the length of the first folding part (FDP1) in the third direction (D3) may exceed 3 mm. Specifically, the length of the first folding part (FDP1) in the third direction (D3) may be 4 mm to 50 mm, 4 mm to 40 mm, or 5 mm to 40 mm. If the length of the first folding part (FDP1) in the third direction (D3) is 3 mm or less, it may be difficult to withstand the internal pressure generated during pressurized driving. In other words, there is a high risk of pouch damage.

[0175] Referring again to FIG. 7a and FIG. 8a, in one embodiment, the pouch-type all-solid-state battery (PCL) may further include a fixing member (TPE) for fixing a first folding portion (FDP1). One end of the fixing member (TPE) may be attached to the first folding portion (FDP1), and the other end may be attached to the first outer material (POH1) to fix the first folding portion (FDP1). For example, the other end of the fixing member (TPE) may be attached to the outer bottom surface of the first receiving portion (REP1) to fix the first folding portion (FDP1).

[0176] In one embodiment, the fixing member (TPE) may be an adhesive tape.

[0177] In one embodiment, the fixed member (TPE) may be extended in a second direction (D2) along the first folding portion (FDP).

[0178] FIG. 8c is a cross-sectional view for explaining an adhesive member, which is a modified embodiment of the fixing member described above with reference to FIG. 8a.

[0179] Referring to FIG. 8c, the fixing member may be an adhesive member (ADM). The adhesive member (ADM) may be attached between the first folding part (FDP1) and the first exterior material area, and specifically, one end of the adhesive member (ADM) may be attached to the first folding part (FDP1) and the other end may be attached to the first exterior material area to fix the first folding part (FDP1).

[0180] In one embodiment, the adhesive member (ADM) may be an adhesive comprising a polymer resin. As an example, the adhesive member (ADM) may comprise at least one of a polyurethane resin, an epoxy resin, an acrylic resin, a polyimide resin, and a polyolefin resin.

[0181] In one embodiment, the adhesive member (ADM) may be extended in a second direction (D2).

[0182] FIG. 8d illustrates a modified embodiment of the adhesive member described above with reference to FIG. 8c.

[0183] Referring to FIG. 8d, in one embodiment, the bottom surface and the top surface of the adhesive member (ADM) may be unclear. The end portion of the adhesive member (ADM) may not protrude beyond the minimum operating thickness of the pouch-type all-solid-state battery.

[0184] Referring to FIG. 8c, the end portion of the adhesive member (ADM) may not protrude beyond the minimum operating thickness of the pouch-type all-solid-state battery. In one embodiment, the top portion of the adhesive member (ADM) (or the highest point MAH in the third direction (D3); see FIG. 8d) may be lower than the top surface (CTS) of the pouch-type all-solid-state battery. That is, the adhesive member (ADM) may not protrude higher than the top surface (CTS) of the pouch-type all-solid-state battery. In one embodiment, the height difference between the end portion of the adhesive member (ADM) and the top and bottom surfaces of the pouch-type all-solid-state battery may be 1 mm or more. For example, when the first folding portion (FDP1) is folded upward, the height difference between the top portion of the adhesive member (ADM) and the top surface (CTS) of the pouch-type all-solid-state battery may be 1 mm or more. As another example, when the first folding portion is folded downward, the height difference between the bottom of the adhesive member (ADM) and the bottom surface of the pouch-type all-solid-state battery may be 1 mm or more.

[0185] In other words, the first height (H1), which is the uppermost part of the adhesive member (ADM) in the third direction (D3), may be smaller than the second height (H2), which is the straight distance in the third direction from the bottom surface of the adhesive member (ADM) to the top surface (CTS) of the pouch-type all-solid-state battery. Specifically, the second height (H2) may be at least 1 mm larger than the first height (H1). Through this, interference of the adhesive member (ADM) during pressurized driving can be prevented.

[0186] In one embodiment, referring to FIG. 8d, the first height (H1) of the adhesive member (ADM) may be a straight distance in the third direction (D3) from the lowest point (MIH) of the adhesive member (ADM) to the highest point (MAH). In that case, the second height (H2) described above with reference to FIG. 8c may be a value measured from the lowest point (MIH) of the adhesive member (ADM).

[0187] In one embodiment, the second height (H2) may be measured when the pouch-type all-solid-state battery (PCL) is pressurized to the driving pressure (DP) described above.

[0188] In one embodiment, the second height (H2) may be measured in the maximum discharge state of the pouch-type all-solid-state battery (PCL). The maximum discharge state may be a state where the SOC is about 1% or less, and specifically, a state where the SOC is 0%.

[0189] For example, the second height (H2) may be measured in a maximum discharge state while the pouch-type all-solid-state battery (PCL) is pressurized to the driving pressure (DP) described above.

[0190] FIG. 9 is an enlarged view illustrating a first folding part according to another embodiment. Detailed descriptions of technical features that overlap with those previously described are omitted, and the differences are described in detail.

[0191] Referring to FIG. 9, the first folding part (FDP1) can be folded so as not to be in direct contact with the first exterior material area (POR1), even though it is adjacent to it.

[0192] In one embodiment, the folding angle (θ) formed by the first folding part (FDP1) with the first direction (D1) may be 50° to 90°. If the folding angle (θ) is less than the above range, it may come into contact with the outer surface of the first exterior material area (POR1), and as a result, the first folding part (FDP1) may interfere with the pressurization during pressurized driving, and as a result, cell performance may be degraded.

[0193] FIG. 10 is an enlarged view illustrating a first folding part according to another embodiment. Detailed descriptions of technical features that overlap with those previously described are omitted, and the differences are described in detail.

[0194] Referring to FIG. 10, the first folding part (FDP1) may be folded two or more times, specifically double-folded.

[0195] As described above with reference to FIG. 8a, in one embodiment, the ratio (TL / TK1) of the length (TL) of the first folding portion (FDP1) in the third direction (D3) to the first thickness (TK1) may be 0.4 to 0.8. The length (TL) of the first folding portion (FDP1) in the third direction (D3) refers to the maximum length in the third direction (D3).

[0196] As described above with reference to FIG. 8b, in one embodiment, the length (TL) of the first folding part (FDP1) in the third direction (D3) may be smaller than the minimum driving thickness.

[0197]

[0198] Hereinafter, embodiments and comparative examples of the present invention are described. However, the following embodiments are merely examples of the present invention, and the present invention is not limited to the following embodiments.

[0199]

[0200] Example 1-1

[0201] (Pouch exterior material)

[0202] Two identical exterior materials (first exterior material, second exterior material) with gas pockets and receiving portions formed were prepared.

[0203] (Electrode assembly)

[0204] 1. Anode manufacturing

[0205] LiNi0.8Co0 as positive active material. 15 Mn0. 05O2 (NCM) powder was prepared. As a solid electrolyte, a azirodite-based first solid electrolyte particle (Li6PS5Cl) with an average particle size (D50) of 1 μm was prepared, as a binder, a polyvinylidene fluoride (PVdF) binder was prepared, and as a conductive material, carbon nanofiber (CNF) was prepared.

[0206] A first anode slurry was prepared by mixing these materials in an N-methylpyrrolidone solvent in a weight ratio of anode active material : solid electrolyte : conductive material : binder = 85 : 13.5 : 0.5 : 1. The first anode slurry was coated onto one surface of an aluminum anode current collector and dried and pressed to form an anode.

[0207] 2. Preparation of Solid Electrolyte Layer

[0208] A solid electrolyte slurry was prepared by adding azirodite-based third solid electrolyte particles (Li6PS5Cl) with an average particle size (D50) of 3 μm to an isobutylyl isobutylate binder solution containing a butyl acrylate-based polymer (the mixing ratio of solid electrolyte to binder was 98.7:1.3 by weight). The prepared solid electrolyte slurry was coated onto a release polytetrafluoroethylene film and dried at 60°C for 2 hours to prepare a solid electrolyte layer.

[0209] 3. Cathode Manufacturing

[0210] A cathode coating layer slurry was prepared by mixing 90 wt% of Ag nanoparticles (D50: 60 nm) and 10 wt% of carbon black in a water solvent. The carbon black was a mixture of single particles with a particle size of 38 nm and secondary particles, wherein the secondary particles were formed by assembling primary particles with a particle size of 76 nm and secondary particles with a particle size of 275 nm. The slurry was coated onto a stainless steel foil current collector and then dried to produce a cathode with a cathode coating layer coated on one surface of the current collector.

[0211] 4. Electrode assembly

[0212] An electrode assembly was manufactured by stacking the anode, solid electrolyte layer, and cathode prepared as described above and performing an isohydraulic press at 85°C MPa pressure for about 30 minutes.

[0213]

[0214] (Pouch-type solid-state battery)

[0215] An electrode assembly was placed between the first and second outer materials, in which a gas pocket and a receiving portion were formed, and the outer edges of the first and second outer materials were heat-sealed, and the space between the gas pocket and the receiving portion was heat-sealed to form an all-solid-state battery of the form shown in FIG. 5c. The heat-sealing was performed while pressurizing the receiving portion at 0.8 MPa.

[0216] After that, the space between the gas pocket and the receiving portion was cut to form a pouch-type all-solid-state battery including a first wing portion (see FIG. 5d).

[0217] The pressure was released and the thickness (first thickness, TK1) of the first outer material portion of the pouch-type all-solid-state battery was measured. The measured first thickness is 20 mm.

[0218] The receiving portion of the above pouch-type all-solid-state battery was pressurized to a driving pressure of 2.0 MPa, and the thickness (compressed thickness, PT) of the first outer material portion was measured and then the pressure was released. The measured compressed thickness is 18 mm.

[0219] Finally, the first wing portion was folded parallel to the third direction (folding angle 90°) to form a first folding portion with a folding length (TL) of 16 mm in the third direction. Then, one end of the adhesive tape was attached to the first folding portion and the other end was attached to the outer surface of the first exterior material to fix the first folding portion.

[0220]

[0221] Examples 1-2

[0222] In manufacturing a pouch-type all-solid-state battery, an all-solid-state battery was manufactured in the same manner as in Example 1-1, except that the first folding portion was fixed using an adhesive instead of adhesive tape. That is, the first folding portion was fixed by attaching an epoxy adhesive between the first folding portion and the side of the first outer material area. The epoxy adhesive was made to protrude higher in the third direction than the first folding portion.

[0223] In addition, while the receiving portion of the pouch-type all-solid-state battery is pressurized with the above driving pressure, the epoxy adhesive is positioned so that the highest point of the epoxy adhesive is 2 mm lower than the top surface of the all-solid-state battery.

[0224]

[0225] Examples 1-3

[0226] A pouch-type all-solid-state battery was manufactured in the same manner as in Example 1, except that the epoxy adhesive was positioned such that the highest point of the epoxy adhesive was 1 mm lower than the top surface of the all-solid-state battery while the receiving portion of the pouch-type all-solid-state battery was pressurized by a driving pressure.

[0227]

[0228] Example 2

[0229] A pouch-type all-solid-state battery was manufactured in the same manner as in Example 1, except that the first folding portion was formed such that the folding length (TL) in the third direction was 12 mm.

[0230]

[0231] Example 3

[0232] A pouch-type all-solid-state battery was manufactured in the same manner as in Example 1, except that the first folding portion was formed such that the folding length (TL) in the third direction was 8 mm.

[0233]

[0234] Example 4

[0235] An electrode assembly was manufactured in the same manner as in Example 1, except that the thicknesses of the anode, solid electrolyte layer, and cathode were controlled.

[0236] (Pouch-type solid-state battery)

[0237] An electrode assembly was placed between the first and second outer materials, in which a gas pocket and a receiving portion were formed, and the outer edges of the first and second outer materials were heat-sealed, and the space between the gas pocket and the receiving portion was heat-sealed to form an all-solid-state battery of the form shown in FIG. 5c. The heat-sealing was performed while pressurizing the receiving portion at 0.8 MPa.

[0238] After that, the space between the gas pocket and the receiving portion was cut to form a pouch-type all-solid-state battery including a first wing portion (see FIG. 5d).

[0239] The pressure was released and the thickness (first thickness, TK1) of the first outer material portion of the pouch-type all-solid-state battery was measured. The measured first thickness is 10.0 mm.

[0240] The receiving portion of the above pouch-type all-solid-state battery was pressurized to a driving pressure of 2.0 MPa, and the thickness of the first outer material portion (driving thickness, PT) was measured and then the pressure was released. The measured driving thickness is 7.5 mm.

[0241] Finally, the first wing portion was folded parallel to the third direction (folding angle 90°) to form a first folding portion with a folding length (TL) of 5.0 mm in the third direction. Then, one end of the adhesive tape was attached to the first folding portion and the other end was attached to the outer surface of the first exterior material to fix the first folding portion.

[0242]

[0243] Example 5

[0244] A pouch-type all-solid-state battery was manufactured in the same manner as in Example 4, except that the first folding portion was formed such that the folding length (TL) in the third direction was 6.0 mm and the folding angle was 80°.

[0245]

[0246] Comparative Example 1

[0247] A pouch-type all-solid-state battery was manufactured in the same manner as in Example 1-1, except that the first folding portion was formed such that the folding length (TL) in the third direction was 18.5 mm.

[0248]

[0249] Comparative Example 2

[0250] A pouch-type all-solid-state battery was manufactured in the same manner as in Example 4-1, except that the first folding portion was formed such that the folding length (TL) in the third direction was 8.0 mm.

[0251]

[0252] Comparative Example 3

[0253] A pouch-type all-solid-state battery was manufactured in the same manner as in Example 4-1, except that the first folding portion was formed such that the folding length (TL) in the third direction was 3.0 mm.

[0254]

[0255] Comparative Example 4

[0256] A pouch-type all-solid-state battery was manufactured in the same manner as in Example 1-1, except that the first folding portion was formed such that the folding length (TL) in the third direction was 12.0 mm and the folding angle was 40°.

[0257]

[0258] Comparative Example 5

[0259] A pouch-type all-solid-state battery was manufactured in the same manner as in Examples 1-2, except that the epoxy adhesive was positioned so that the highest point of the epoxy adhesive protruded 1 mm higher than the top surface of the all-solid-state battery while the receiving portion of the pouch-type all-solid-state battery was pressurized by a driving pressure.

[0260]

[0261] Comparative Example 6

[0262] A pouch-type all-solid-state battery was manufactured in the same manner as in Examples 1-2, except that the epoxy adhesive was positioned so that the highest point of the epoxy adhesive was substantially equal to the height of the top surface of the all-solid-state battery while the receiving portion of the pouch-type all-solid-state battery was pressurized by a driving pressure.

[0263]

[0264] Comparative Example 7

[0265] A pouch-type all-solid-state battery was manufactured in the same manner as in Examples 1-2, except that the epoxy adhesive was positioned such that the highest point of the epoxy adhesive was 0.5 mm lower than the top surface of the all-solid-state battery while the receiving portion of the pouch-type all-solid-state battery was pressurized by a driving pressure.

[0266]

[0267] The characteristics of pouch-type all-solid-state batteries according to the examples and comparative examples are summarized in Tables 1 and 2 below.

[0268] First Thickness (mm) Driving Thickness (mm) Folding Length (mm) Folding Length / First Thickness Folding Angle (°) Contact between Folding Part and Exterior Material Example 1-1 2018 160.890 No Contact Example 2 2018 120.690 No Contact Example 3 2018 80.490 No Contact Example 4 107.55 0.590 No Contact Example 5 107.56 0.680 No Contact Comparative Example 1 2018 18.5 0.92590 No Contact Comparative Example 2 107.58 0.890 No Contact Comparative Example 3 107.53 0.390 No Contact Comparative Example 4 2018 120.640 Contact

[0269] H2-H1 (mm) First thickness (mm) Driving thickness (mm) Folding length (mm) Folding length / First thickness Example 1-2 2018 160.8 Example 1-3 12018 160.8 Comparative Example 5-1 2018 160.8 Comparative Example 6 2018 160.8 Comparative Example 7 0.5 2018 160.8 H2-H1: Height difference between the upper surface of the pouch-type all-solid-state battery and the top of the adhesive

[0270] Evaluation Example 1: Evaluation of Pouch Life Characteristics

[0271] Five all-solid-state batteries were manufactured according to the examples and comparative examples, respectively. The batteries were charged and discharged while being pressurized at a driving pressure of 2 MPa. After performing 50 charge-discharge cycles on each battery, the results regarding whether the sealing of the first wing portion was released and whether the pouch was damaged (whether the first folding portion was damaged) are shown in Tables 3 and 4 below.

[0272]

[0273] Evaluation Example 2: Evaluation of Cell Lifetime Characteristics

[0274] Charges and discharges of all-solid-state batteries were performed according to the examples and comparative examples. The first charge and discharge were performed under the following conditions: charging (0.33C CC / CV charge 4.25V 0.05C cut) and discharging (0.33C CC discharge 3.0V cut). From the second charge and discharge onwards, the following conditions were performed: charging (1.0C CC / CV charge 4.25V 0.05C cut) and discharging (0.5C CC discharge 3.0V cut). After performing 20 continuous charge and discharge cycles, the state of health (SOH) was measured and is shown in Tables 3 and 4. The state of health at the 20th cycle (20cyc) was calculated using the following Equation 1.

[0275] [Equation 1]

[0276] 20-cycle capacity retention rate [%] = [Discharge capacity at the 20th cycle / Discharge capacity at the 1st cycle] × 100

[0277] Cell Production Quantity Folding Part Sealing Release Status Folding Part Damage Status Capacity Retention Rate @20 cyc (%) Specific Appearance Details Example 1 - 15 pieces XX95 - Example 25 pieces XX92 - Example 35 pieces XX90 - Example 45 pieces XX93 - Example 55 pieces XX95 - Comparative Example 15 pieces XO (4 pieces) 87 Non-uniform Pressurization Shape Comparative Example 25 pieces XO (3 pieces) 75 Non-uniform Pressurization Shape Comparative Example 35 pieces O (2 pieces) X80 Micro-vacuum Release Comparative Example 45 pieces XO (2 pieces) 79-

[0278] Referring to Table 3, it can be seen that the pouch-type all-solid-state batteries according to Comparative Examples 1 and 2, in which the length of the folding portion in the third direction is greater than the driving thickness, have their folding portion damaged by the pressure jig. Additionally, it can be seen that the batteries have poor lifespan characteristics because uniform pressure is not applied.

[0279] In addition, it can be confirmed that the pouch-type all-solid-state battery according to Comparative Example 3 has a short folding length, so it cannot withstand pressure during pressurized charging and discharging, and the sealing of the folding part is released.

[0280] In addition, it can be confirmed that the pouch-type all-solid-state battery according to Comparative Example 4 has a small folding angle, causing the folding part and the outer material to come into contact, and as a result, damage occurs to the folding part and the lifespan characteristics deteriorate during pressurized charging and discharging.

[0281] On the other hand, the pouch-type all-solid-state batteries according to Examples 1-1 and 2 to 5 have an appropriate folding length so that the folding part does not interfere with the pressurization during pressurized charging and discharging, and it can be confirmed that the battery life characteristics are excellent due to uniform pressurization.

[0282] Cell Production Quantity Whether Folding Part Sealing Is Released Whether Folding Part Is Damaged Capacity Retention Rate @ 20 CYC (%) Specific Appearance Example 1 - 25 pieces XX95 Example 1 - 35 pieces XX94 Comparative Example 55 pieces XO (4 pieces) 72 Non-uniform Pressurization Shape Comparative Example 65 pieces XO (3 pieces) 75 Non-uniform Pressurization Shape Comparative Example 75 pieces XO (2 pieces) 89 Non-uniform Pressurization Shape

[0283] Referring to Table 4, it can be seen that the lifespan characteristics are significantly degraded when the highest point of the adhesive protrudes higher than the top surface of the pouch-type all-solid-state battery (Comparative Example 5). In addition, it can be seen that the lifespan characteristics are poor even if the highest point of the adhesive is nearly the same as or lower than the top surface of the pouch-type all-solid-state battery, but the difference is less than 1 mm (Comparative Examples 6 and 7).

Claims

1. A pouch-type all-solid-state battery comprising an electrode assembly containing a solid electrolyte and a pouch outer material accommodating the electrode assembly, wherein The above pouch outer material includes a first outer material and a second outer material arranged to face each other to package the electrode assembly, and The first outer material surrounds at least a portion of the electrode assembly and forms a first outer material region of the all-solid-state battery, and The above pouch outer material includes a first wing portion formed by sealing the first and second outer materials together, and The above-mentioned first wing portion includes a first folding portion formed by folding, and A pouch-type all-solid-state battery, wherein the first folding portion is formed so as not to protrude beyond the minimum driving thickness of the first exterior material area.

2. In Paragraph 1, A pouch-type all-solid-state battery in which the length in the third direction, which is the thickness direction of the pouch-type all-solid-state battery of the first folding part, is 4 mm to 50 mm.

3. In Paragraph 1, With the pressure applied to the above pouch-type all-solid-state battery released, the first outer material region has a first thickness which is a thickness in the third direction, and A pouch-type all-solid-state battery in which the length ratio of the first folding portion in the third direction to the first thickness is 0.4 to 0.

8.

4. In Paragraph 3, A pouch-type all-solid-state battery, wherein the first thickness is the thickness when the remaining capacity (SOC) of the pouch-type all-solid-state battery is 1% or less.

5. In Paragraph 1, The above minimum driving thickness is: While the above pouch-type all-solid-state battery is in a state where it is pressurized by a driving pressure, A pouch-type solid-state battery having a thickness when the remaining capacity (SOC) of the above pouch-type solid-state battery is 1% or less.

6. In Paragraph 1, A pouch-type all-solid-state battery having a driving pressure of 1 MPa to 5 MPa.

7. In Paragraph 1, The above pouch outer material further includes a second wing portion formed by sealing the first and second outer materials together, and The first and second wing portions are spaced apart from each other in the first direction, and A pouch-type all-solid-state battery, wherein each of the first and second wing portions extends in a second direction intersecting the first direction.

8. In Paragraph 7, The above pouch outer material further includes a front sealing portion and a rear sealing portion formed by sealing the first and second outer materials together, and The above front sealing portion and the above rear sealing portion are spaced apart from each other in the second direction, and A pouch-type all-solid-state battery in which the front sealing portion and the rear sealing portion each extend in the first direction.

9. In Paragraph 8, A first lead tab adjacent to the front sealing portion; and A pouch-type all-solid-state battery further comprising a second lead tab adjacent to the rear sealing portion.

10. In Paragraph 1, A pouch-type solid-state battery in which the first wing portion is located on the long axis portion of the solid-state battery.

11. In Paragraph 1, It further includes an adhesive member for fixing the first folding part, A pouch-type all-solid-state battery in which the end portion of the adhesive member does not protrude beyond the minimum driving thickness of the first outer material area.

12. In Paragraph 1, A pouch-type all-solid-state battery, wherein the first wing portion is formed by heat fusion.

13. In Paragraph 1, A pouch-type all-solid-state battery in which the folding angle of the first folding part is 50° to 90°.

14. A pouch-type all-solid-state battery comprising an electrode assembly containing a solid electrolyte and a pouch outer material accommodating the electrode assembly, wherein The above pouch outer material includes a first outer material and a second outer material arranged to face each other to package the electrode assembly, and The first outer material surrounds at least a portion of the electrode assembly and forms a first outer material region of the all-solid-state battery, and The above pouch outer material includes a first wing portion formed by sealing the first and second outer materials together, and The first wing portion includes a first folding portion formed by folding toward the first exterior material area, and The above-described all-solid-state battery includes an adhesive member attached between the first folding portion and the first exterior material region to fix the first folding portion, wherein A pouch-type all-solid-state battery in which the end portion of the adhesive member does not protrude beyond the minimum driving thickness of the first outer material area.

15. In Paragraph 14, A pouch-type all-solid-state battery in which the length of the first folding portion in the third direction is 4 mm to 50 mm.

16. In Paragraph 14, The first folding portion above does not protrude beyond the minimum driving thickness of the first exterior material area, and A pouch-type solid-state battery, wherein the minimum driving thickness is the thickness when the all-solid-state battery is pressurized with driving pressure and the remaining capacity (SOC) of the pouch-type solid-state battery is 1% or less.

17. Packaging an electrode assembly in a pouch outer material comprising a first outer material and a second outer material arranged to face each other, wherein the pouch outer material comprises a gas pocket and a receiving portion for receiving the electrode assembly; Sealing the outer edge of the above pouch outer material; Sealing and cutting between the gas pocket and the receiving portion to form a first wing portion in which the first and second exterior materials are sealed together; and The method includes folding the first wing portion to form a first folding portion, wherein The first outer material surrounds at least a portion of the electrode assembly and forms a first outer material region of the all-solid-state battery, and A method for manufacturing a pouch-type all-solid-state battery in which the first folding portion does not protrude beyond the minimum driving thickness of the first outer material area:

18. In Paragraph 17, In the state where the pressure of the above pouch-type all-solid-state battery is released, the first outer material region has a first thickness which is a thickness in the third direction, and A method for manufacturing a pouch-type all-solid-state battery, wherein the length ratio of the first folding portion in the third direction to the first thickness is 0.4 to 0.

8.

19. In Paragraph 17, A method for manufacturing a pouch-type all-solid-state battery, wherein the length of the first folding part in the third direction is 4 mm to 50 mm.

20. In Paragraph 17, It further includes fixing the first folding part above, and Fixing the first folding portion includes attaching an adhesive member between the first folding portion and the first exterior material area, wherein A method for manufacturing a pouch-type all-solid-state battery in which the end portion of the adhesive member does not protrude beyond the minimum driving thickness of the first outer material area.

Images