Internal pressure-maintaining plate for all-solid-state battery and all-solid-state battery module including same

Abstract

The present invention relates to an internal pressure-maintaining plate for an all-solid-state battery and an all-solid-state battery module including same. More specifically, a porous layer including a metal foam; a first support layer on the upper surface of the porous layer; and a second support layer on the lower surface of the porous layer are included. The internal pressure-maintaining plate for an all-solid-state battery has a plateau section in which a change in stress is 10 MPa or less when the strain increases by 0.1 or more in a stress-strain curve, and the stress in the plateau section is 1 MPa to 40 MPa.

Description

Pressure-retaining plate for all-solid-state battery and all-solid-state battery module including the same

[0001] The present invention relates to a pressure-retaining plate for an all-solid-state battery and an all-solid-state battery module including the same.

[0002]

[0003] The recent rapid proliferation of battery-powered electronic devices, such as mobile phones, laptops, and electric vehicles, has led to a rapid increase in demand for high-energy density, high-capacity secondary batteries. Accordingly, active research and development is underway to improve the performance of lithium secondary batteries.

[0004] A lithium secondary battery is a battery that includes a positive electrode and a negative electrode that contain active materials capable of intercalating and deintercalating lithium ions, and an electrolyte, and produces electrical energy through oxidation and reduction reactions when lithium ions are intercalated / deintercalated from the positive electrode and negative electrode.

[0005] Meanwhile, all-solid-state batteries are being proposed, replacing the electrolyte with a solid electrolyte. By eliminating the use of flammable organic dispersion media, all-solid-state batteries can significantly reduce the risk of fire or explosion in the event of a short circuit.

[0006]

[0007] The problem to be solved by the present invention is to provide an internal pressure maintaining plate capable of effectively controlling pressure changes within a battery module.

[0008] Another problem to be solved by the present invention is to provide a battery module including the pressure-retaining plate.

[0009] A pressure-retaining plate for an all-solid-state battery according to the concept of the present invention may include a porous layer including metal foam; a first support layer on an upper surface of the porous layer; and a second support layer on a lower surface of the porous layer. The pressure-retaining plate for an all-solid-state battery may have a plateau section in which a stress change amount is 10 MPa or less when a strain increases by 0.1 or more in a stress-strain curve, and the stress in the plateau section may be 1 MPa to 40 MPa.

[0010] According to another concept of the present invention, a pressure-retaining plate for an all-solid-state battery may include a porous layer including a first metal foam, a second metal foam, and a third metal foam, the second metal foam being adjacent to the first metal foam in a second direction, and the third metal foam being adjacent to the first metal foam in the first direction; a first support layer on an upper surface of the porous layer; and a second support layer on a lower surface of the porous layer. The first metal foam and the second metal foam may be spaced apart from each other by a first space, and the first metal foam and the third metal foam may be spaced apart from each other by a second space, and the first space and the second space may be different from each other.

[0011] An all-solid-state battery module according to another concept of the present invention may include a first battery cell; a second battery cell; and a pressure-retaining plate provided between the first and second battery cells. The pressure-retaining plate may include a porous layer including at least one metal foam; a first support layer on an upper surface of the porous layer; and a second support layer on a lower surface of the porous layer. The pressure-retaining plate may have a plateau section in which a stress change amount is 10 MPa or less when a strain in a stress-strain curve increases by 0.1 or more, and the stress in the plateau section may be 1 MPa to 40 MPa.

[0012]

[0013] The pressure-retaining plate for an all-solid-state battery according to the present invention can prevent damage to an all-solid-state battery and an all-solid-state battery module including the same by maintaining a constant internal pressure within the module resulting from expansion of the all-solid-state battery. In addition, this can improve the lifespan characteristics of the all-solid-state battery.

[0014] According to another concept of the present invention, a pressure-retaining plate for an all-solid-state battery can improve energy density and enhance pressure-retaining effect by arranging metal foams at predetermined intervals in a porous layer.

[0015] An all-solid-state battery module according to another concept of the present invention has excellent stability and can improve the life characteristics of the internal all-solid-state battery by including an internal pressure-maintaining plate for the all-solid-state battery.

[0016]

[0017] Figure 1 is a cross-sectional view of an all-solid-state battery according to one embodiment of the present invention.

[0018] Figure 2 is a perspective view of an all-solid-state battery module according to one embodiment of the present invention.

[0019] Figure 3 is a cross-sectional view of a pressure-retaining plate for an all-solid-state battery according to one embodiment of the present invention.

[0020] Figure 4 is an exploded schematic diagram of the internal pressure maintaining plate for the all-solid-state battery of Figure 3.

[0021] Fig. 5 is a cross-sectional view of a pressure-retaining plate for an all-solid-state battery according to another embodiment.

[0022] Fig. 6 is a cross-sectional view of a pressure-retaining plate for an all-solid-state battery according to another embodiment.

[0023] Figure 7 is a plan view of a porous layer in the pressure-retaining plate for the all-solid-state battery of Figure 6.

[0024] Fig. 8 is a cross-sectional view of a pressure-retaining plate for an all-solid-state battery according to another embodiment.

[0025] Figure 9 is an exploded schematic diagram of the internal pressure maintaining plate for the all-solid-state battery of Figure 8.

[0026] Figure 10 is a plan view of a porous layer in the pressure-retaining plate for the all-solid-state battery of Figure 8.

[0027] Figure 11 is a stress-strain graph of a pressure-retaining plate for an all-solid-state battery according to one embodiment.

[0028] Figure 12 is a graph showing the effect of improving cell life characteristics due to control of swelling force of an all-solid-state battery module.

[0029]

[0030] To fully understand the structure and effects of the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and subject to various modifications. However, the description of these embodiments is provided solely to ensure a complete disclosure of the present invention and to fully inform those skilled in the art of the invention of the scope of the invention.

[0031] In this specification, when a component is referred to as being on another component, it means that it can be formed directly on the other component, or a third component may be interposed between them. Furthermore, in the drawings, the thicknesses of the components are exaggerated for the sake of clarity. Parts designated by the same reference numerals throughout the specification represent the same components.

[0032] Unless otherwise specified herein, the singular may also include the plural. Furthermore, unless otherwise specified, "A or B" may mean "including A, including B, or including A and B." As used herein, "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components.

[0033] As used herein, “combination thereof” may mean mixtures, laminates, composites, copolymers, alloys, blends, and reaction products of the components.

[0034]

[0035] FIG. 1 is a cross-sectional view illustrating an all-solid-state battery according to one embodiment of the present invention. Referring to FIG. 1, an all-solid-state battery (10) according to one embodiment of the present invention is illustrated. 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, the present invention is not limited thereto, and 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).

[0036] The positive electrode layer (100) may include a positive electrode current collector (110) and a positive electrode active material layer (120) disposed on the positive electrode current collector (110). The positive electrode active material layer (120) may include a positive electrode active material, a solid electrolyte, a conductive material, and a binder.

[0037] The positive electrode current collector (110) can provide a reference surface on which the positive electrode active material layer (120) is arranged. The positive electrode current collector (110) can have a plate or foil shape. For example, the positive electrode current collector (110) can 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.

[0038] Unlike that illustrated in FIG. 1, in one embodiment of the present invention, the positive electrode current collector (110) may be omitted. Although not illustrated, a carbon layer having a thickness of 0.1 μm to 4 μm may be additionally disposed between the positive electrode current collector (110) and the positive electrode active material layer (120) to increase the bonding strength between the positive electrode current collector (110) and the positive electrode active material layer (120).

[0039] The cathode active material may be a material that can reversibly absorb and desorb lithium ions. For example, the cathode active material may include, but is not limited to, 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. The cathode active materials may be used alone or as a mixture of two or more thereof.

[0040] Lithium transition metal oxides include, for example, Li a A 1-b B b D2(0.90≤a≤1, 0≤b≤0.5), Li a E 1-b Bb 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 Ni 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 Ni 1-b-c Mr b B c D α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α≤2), Li a Ni 1-b-c Mr 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 Ni b HAVE BEEN c G d O2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0.001≤d≤0.1), Li a Ni b Co c Mr 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 bO2(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-f It may be a compound represented by any one of Fe2(PO4)3(0≤f≤2), LiFePO4. In these compounds, the capital letter “A” is Ni, Co, Mn, or a combination thereof, the capital letter “B” is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof, the capital letter “D” is O, F, S, P, or a combination thereof, the capital letter “E” is Co, Mn, or a combination thereof, the capital letter “F” is F, S, P, or a combination thereof, the capital letter “G” is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof, the capital letter “Q” is Ti, Mo, Mn, or a combination thereof, the capital letter “I” is Cr, V, Fe, Sc, Y, or a combination thereof, and the capital letter “J” is V, Cr, Mn, Co, Ni, Cu, or a combination thereof.

[0041] The cathode 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 atomic layers and metal atomic layers are arranged alternately and regularly in the direction, and each atomic layer thereby forms a two-dimensional plane. The "cubic rock salt structure" refers to the sodium chloride type (NaCl type) structure, which is a type of crystal structure, and specifically refers to a structure in which the face-centered cubic lattice (fcc) formed by each cation and anion is arranged with a displacement of half of the ridge of the unit lattice. Lithium transition metal oxides having this layered rock salt structure include, for example, LiNi x Co y Al z O2(NCA) or LiNi x Co y Mn z 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.

[0042] The above-described compound included 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 above-described compound and a compound to which a coating layer is added. Meanwhile, the coating layer added to the surface of the positive electrode active material may include, for example, an oxide, a hydroxide, an oxyhydroxide, an oxycarbonate, or a hydroxycarbonate of the coating elements below. The compound forming the 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, a spray coating method or an immersion method.

[0043] When the positive electrode active material includes nickel (Ni) as a ternary lithium transition metal oxide such as NCA or NCM, for example, the capacity density of the all-solid-state battery (10) can be increased, thereby reducing metal dissolution of the positive electrode active material in a charged state. As a result, the cycle characteristics of the all-solid-state battery (10) in a charged state can be improved. Meanwhile, the “cycle characteristics” are characteristics indicating the degree to which the all-solid-state battery (10) is deteriorated due to charge / discharge of the all-solid-state battery (10). An all-solid-state battery (10) with high cycle characteristics can have a small degree of deterioration of the all-solid-state battery (10) due to charge / discharge, and an all-solid-state battery (10) with low cycle characteristics can have a large degree of deterioration of the all-solid-state battery (10) due to charge / discharge.

[0044] The shape of the positive electrode active material may include particle shapes such as a sphere or an ellipsoid, for example. The particle size and content of the positive electrode active material are not particularly limited.

[0045] The solid electrolyte may include a sulfide-based solid electrolyte having excellent lithium ion conductivity characteristics. Examples of the sulfide-based solid electrolyte include Li2S-P2S5, Li2S-P2S5-LiX (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, Li2S-P2S5-Z. m S n (m, n are positive numbers, capital letter “Z” represents Ge, Zn or Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li p MO q (p, q are positive numbers, capital letter “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).

[0046] Sulfide-based solid electrolytes include, 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(0≤x≤2) may be an argyrodite-type compound including at least one selected from. In particular, the sulfide-based solid electrolyte may be an argyrodite-type compound including at least one 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. Since the argyrodite-type solid electrolyte has a density of 1.5 g / cc or more, the internal resistance of the all-solid-state battery is reduced, and the defect of the solid electrolyte membrane being penetrated and short-circuited due to the formation of lithium dendrites can be prevented. The elastic modulus of the solid electrolyte may be, for example, 15 GPa to 35 GPa.

[0047] The solid electrolyte included in the positive electrode active material layer (120) may have a smaller median particle size (D50) than the solid electrolyte included in the solid electrolyte layer (300). For example, the median 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 median particle size (D50) of the solid electrolyte included in the solid electrolyte layer (300). Meanwhile, the median particle size (D50) may be a median diameter measured using a laser particle size distribution meter.

[0048] The positive electrode active material layer (120) may include a conductive material. The conductive material may have conductivity without causing a chemical change in the all-solid-state battery (10), thereby increasing the conductivity of the positive electrode 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.

[0049] The positive electrode active material layer (120) may further include a binder. The binder may include a material for binding the positive electrode active material, solid electrolyte, and conductive material included in the positive electrode active material layer (120) and improving bonding strength with the positive electrode 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.

[0050] When the total amount of the positive electrode active material, the solid electrolyte, the conductive material, and the binder is 100 parts by weight, the positive electrode active material layer (120) may include 85 parts by weight to 92 parts by weight of the positive electrode active material. The positive electrode active material layer (120) may include 0.5 parts by weight to 1.5 parts by weight of the binder.

[0051] Within the positive electrode active material layer (120), the conductive material may be present in an amount of 1 to 50 parts by weight relative to 100 parts by weight of the solid electrolyte. If the conductive material is present in an amount less than 1 part by weight relative to 100 parts by weight of the solid electrolyte, the electrical conductivity of the positive electrode active material layer (120) may be reduced. If the conductive material is present in an amount greater than 50 parts by weight relative to 100 parts by weight of the solid electrolyte, the conductive material ratio may be excessively high, and thus a covering layer covering the surface of the solid electrolyte may not be properly formed.

[0052] According to embodiments, the positive electrode 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 conductive auxiliary agent in addition to the above-described positive electrode active material, solid electrolyte, conductive agent, and binder.

[0053] 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 having 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 positive electrode active material layer (120) described above.

[0054] The solid electrolyte layer (300) of one embodiment may include a sulfide-based solid electrolyte. The sulfide-based solid electrolyte may be manufactured by treating starting materials such as Li2S and P2S5 by a melting rapid cooling method or a mechanical milling method. In addition, a heat treatment may be performed after the treatment. The solid electrolyte may be amorphous, crystalline, or a mixture thereof. In addition, the solid electrolyte may include, for example, at least sulfur (S), phosphorus (P), and lithium (Li) as constituent elements among the above-described sulfide-based solid electrolyte materials. For example, the solid electrolyte may be a material including Li2S-P2S5. When using a sulfide-based solid electrolyte material including Li2S-P2S5 to form the solid electrolyte, the mixing molar ratio of Li2S and P2S5 is, for example, in the range of Li2S:P2S5=50:50 to 90:10.

[0055] Sulfide-based solid electrolytes include, 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(0≤x≤2) may be an argyrodite-type compound including at least one selected from. In particular, the sulfide-based solid electrolyte may be an argyrodite-type compound including at least one 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. Since the argyrodite-type solid electrolyte has a density of 1.5 g / cc or more, the internal resistance of the all-solid-state battery is reduced, and the defect of the solid electrolyte membrane being penetrated and short-circuited due to the formation of lithium dendrites can be prevented. The elastic modulus of the solid electrolyte is, for example, 15 GPa to 35 GPa.

[0056] The solid electrolyte layer (300) may further include a binder. The binder in the solid electrolyte layer (300) may be, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc., but is not limited thereto. The binder of the solid electrolyte layer (300) may be the same as or different from the binder included in the positive electrode active material layer (120) or the binder included in the negative electrode coating layer (220).

[0057] The negative electrode layer (200) may include a negative electrode current collector (210) and a negative electrode coating layer (220) on the negative electrode current collector (210). The negative electrode current collector (210) may provide a reference surface on which the negative electrode coating layer (220) is disposed. The negative electrode current collector (210) may include, for example, a material that does not react with lithium, i.e., does not form an alloy or a compound 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.

[0058] The negative electrode current collector (210) may be composed of one of the above-described metals, or may include an alloy or coating material of two or more metals. The negative electrode current collector (210) may have, for example, a plate shape or a foil shape. Meanwhile, in one embodiment, the negative electrode current collector (210) may be omitted.

[0059] The negative electrode coating layer (220) can allow lithium metal to grow between it and the negative electrode current collector (210) when the all-solid-state battery (10) is charged. The negative electrode coating layer (220) can act as a protective layer for the lithium metal and simultaneously suppress the precipitation and growth of lithium dendrites.

[0060] The cathode coating layer (220) may include a metal and carbon. For example, the cathode 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 cathode 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 cathode coating layer (220) may include a mixture of carbon black and silver (Ag).

[0061] The cathode coating layer (220) may further include additives other than metal and carbon. The cathode coating layer (220) may further include, for example, at least one additive selected from the group consisting of a binder, a filler, a coating agent, a dispersant, and an ion conductive additive.

[0062] The negative electrode coating layer (220) may have a smaller thickness than the positive electrode active material layer (120). The thickness of the negative electrode 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 electrode active material layer (120). The thickness of the negative electrode coating layer (220) may be, for example, 1 um to 20 um, 2 um to 10 um, or 3 um to 7 um. If the thickness of the negative electrode coating layer (220) is too thin, lithium dendrites formed between the negative electrode coating layer (220) and the negative electrode current collector (210) may cause the negative electrode coating layer (220) to collapse, thereby deteriorating the cycle characteristics of the all-solid-state battery (10). If the thickness of the cathode coating layer (220) increases excessively, the energy density of the all-solid-state battery (10) may decrease and the internal resistance of the all-solid-state battery (10) due to the cathode coating layer (220) may increase, thereby deteriorating the cycle characteristics of the all-solid-state battery (10).

[0063] Meanwhile, although not shown, a carbon layer may be further included to improve adhesion between the cathode coating layer (220) and the solid electrolyte layer (300).

[0064] According to embodiments of the present invention, the width (or width) of the anode layer (100) may be the same as the width (or width) of the cathode layer (200). For example, the anode layer (100) may have a first width (W1) in a first direction (D1), and the cathode layer (200) may have a second width (W2) in the first direction (D1). The first width (W1) may be the same as the second width (W2).

[0065] According to embodiments of the present invention, the width (or widths) of the anode layer (100) may be smaller than the width (or widths) of the cathode layer (200). For example, the first width (W1) may be smaller than the second width (W2).

[0066] According to embodiments of the present invention, the width (or widths) of the anode layer (100) may be greater than the width (or widths) of the cathode layer (200). For example, the first width (W1) may be greater than the second width (W2).

[0067] The solid electrolyte layer (300) may include a positive electrode electrolyte layer (300a) and a negative electrode electrolyte layer (300b). The positive electrode electrolyte layer (300a) and the negative electrode electrolyte layer (300b) may be laminated to form a single solid electrolyte layer (300). The positive electrode electrolyte layer (300a) may be in contact with the positive electrode active material layer (120), and the negative electrode electrolyte layer (300b) may be in contact with the negative electrode coating layer (220).

[0068] In one embodiment of the present invention, the positive electrolyte layer (300a) and the negative electrolyte layer (300b) may include solid electrolytes having the same composition. In another embodiment of the present invention, the positive electrolyte layer (300a) and the negative electrolyte layer (300b) may include solid electrolytes having different compositions.

[0069] FIG. 2 is a perspective view illustrating an all-solid-state battery module according to one embodiment of the present invention.

[0070] Referring to FIG. 2, an all-solid-state battery module (MOD) according to an embodiment of the present invention may include a first battery cell (CEL1); a second battery cell (CEL2); and a pressure-retaining plate (PRP) provided between the first battery cell (CEL1) and the second battery cell (CEL2). The all-solid-state battery module (MOD) may further include a third battery cell (CEL3) and a fifth battery cell (CEL5) provided between the first battery cell (CEL1) and the pressure-retaining plate. The all-solid-state battery module (MOD) may further include a fourth battery cell (CEL4) and a sixth battery cell (CEL6) provided between the second battery cell (CEL2) and the pressure-retaining plate.

[0071] In one embodiment, a first battery cell (CEL1), a third battery cell (CEL3), a fifth battery cell (CEL5), a pressure-retaining plate (PRP), a sixth battery cell (CEL6), a fourth battery cell (CEL4), and a second battery cell (CEL2) may be sequentially provided in a third direction (D3) within an all-solid-state battery module (MOD).

[0072] In another embodiment, although not shown, two or more pressure-retaining plates (PRPs) may be provided within the all-solid-state battery module (MOD). For example, a first battery cell (CEL1), a pressure-retaining plate (PRP), a third battery cell (CEL3), a fifth battery cell (CEL5), a pressure-retaining plate (PRP), a sixth battery cell (CEL6), a fourth battery cell (CEL4), a pressure-retaining plate (PRP), and a second battery cell (CEL2) may be provided in sequence.

[0073] Each of the first, second, third, fourth, fifth and sixth battery cells (CEL1, CEL2, CEL3, CEL4, CEL5, CEL6) may correspond to the all-solid-state battery described with reference to FIG. 1.

[0074] The pressure-retaining plate (PRP) may be any one of the pressure-retaining plates (PRP) described below with reference to FIGS. 3 to 8.

[0075] Referring again to FIG. 2, the all-solid-state battery module (MOD) may further include an end plate (ENP) provided at one end within the module. For example, within the all-solid-state battery module (MOD), an end plate (ENP), a first battery cell (CEL1), a third battery cell (CEL3), a fifth battery cell (CEL5), a pressure-retaining plate (PRP), a sixth battery cell (CEL6), a fourth battery cell (CEL4), and a second battery cell (CEL2) may be sequentially provided in a third direction (D3).

[0076] In another embodiment, the end plate (ENP) may be provided at each end of the all-solid-state battery module (MOD). For example, in the all-solid-state battery module (MOD), the end plate (ENP), the first battery cell (CEL1), the third battery cell (CEL3), the fifth battery cell (CEL5), the pressure-retaining plate (PRP), the sixth battery cell (CEL6), the fourth battery cell (CEL4), the second battery cell (CEL2), and the end plate (ENP) may be sequentially provided in the third direction (D3).

[0077] The end plate (ENP) is fixed to the solid-state battery module (MOD), thereby preventing deformation of the solid-state battery module (MOD) and controlling the internal pressure of the module.

[0078] A bolt fastening hole (BOH) may be formed on one side of the end plate (ENP). In one embodiment, the outer wall of the all-solid-state battery module (MOD) may include a fixing hole, and the fixing hole may correspond to the bolt fastening hole (BOH) of the end plate (ENP). A bolt may be fastened to the fixing hole and the bolt fastening hole (BOH). By bolt-fastening the outer wall of the all-solid-state battery module (MOD) and the end plate (ENP), the fixing strength of the end plate (ENP) can be improved.

[0079]

[0080] Fig. 3 is a cross-sectional view illustrating a pressure-retaining plate for an all-solid-state battery according to one embodiment of the present invention. Fig. 4 is an exploded schematic diagram of the pressure-retaining plate for an all-solid-state battery of Fig. 3.

[0081] Referring to FIGS. 3 and 4, a pressure-retaining plate (PRP) for an all-solid-state battery may include a porous layer (POL) including a metal foam (MEF); a first support layer (SPL1) on an upper surface of the porous layer (POL); and a second support layer (SPL2) on a lower surface of the porous layer (POL).

[0082] Each of the first and second support layers (SPL1, SPL2) may include silver (Ag), aluminum (Al), copper (Cu), manganese (Mn), gold (Au), nickel (Ni), titanium (Ti), zinc (Zn), iron (Fe), chromium (Cr) or an alloy thereof. For example, each of the first and second support layers (SPL1, SPL2) may include at least one selected from the group consisting of aluminum, copper, manganese, gold, nickel, titanium, zinc, chromium, brass and steel.

[0083] In one embodiment, the first and second support layers (SPL1, SPL2) may be formed of the same material as the metal foam (MEF). By forming the first and second support layers (SPL1, SPL2) of the same material as the metal foam (MEF), the contact resistance between the porous layer (POL) and the first and second support layers (SPL1, SPL2) can be minimized.

[0084] In another embodiment, the thickness of each of the first and second support layers (SPL1, SPL2) in the third direction (D3) may be 10 μm to 500 μm.

[0085] The porous layer (POL) may include a metal foam. The metal foam may include silver (Ag), aluminum (Al), copper (Cu), manganese (Mn), gold (Au), nickel (Ni), titanium (Ti), zinc (Zn), iron (Fe), chromium (Cr), or an alloy thereof. For example, the porous layer (POL) may include at least one selected from the group consisting of aluminum, copper, manganese, gold, nickel, titanium, zinc, chromium, brass, and steel. In one embodiment, the porous layer may be formed of one metal foam extending in a first direction (D1) and a second direction (D2).

[0086] In another embodiment, the width of the porous layer (POL) in the first direction (D1) relative to the width of the first support layer (SPL) in the first direction (D1) may be [0.9 to 1.1]. The length of the porous layer (POL) in the second direction (D2) relative to the length of the first support layer (SPL1) in the second direction (D2) may be 0.9 to 1.1. This allows for uniform distribution of stress by increasing the contact area between the first support layer (SPL) and the porous layer (POL).

[0087] In another embodiment, the thickness of the porous layer (POL) in the third direction (D3) may be [0.5 mm to 5 mm].

[0088] A pressure-retaining plate (PRP) may have a plateau region, which is a region in the stress-strain curve where the stress remains stable after reaching a certain level of stress.

[0089] The plateau region is a region where stress can be stably maintained as pores in the metal foam collapse when the compressive force applied to the pressure-retaining plate (PRP) due to the expansion of the battery cells (CEL) exceeds the elastic critical stress of the metal foam. The pressure-retaining plate (PRP) of the present invention can prevent damage to the all-solid-state battery module (MOD) by maintaining the stress within an appropriate range. In addition, it can prevent interface separation and damage of the battery cells (CEL) included therein and improve the life characteristics (referring to FIG. 12, it can be confirmed that the life characteristics of the battery can be improved by controlling the swelling force generated by the expansion of the battery cells (CEL).

[0090] In one embodiment, the pressure-retaining plate (PRP) can have a plateau region in which the stress change is less than or equal to 10 MPa when the strain (engineering) increases by 0.1 or more.

[0091] In this specification, the stress change refers to the difference between the maximum stress value and the minimum stress value in a given section.

[0092] For example, a pressure-retaining plate (PRP) may have a plateau region in which the difference between the minimum stress and the maximum stress is less than 10 MPa in a region where the strain is between 0.1 and 0.4. Alternatively, the pressure-retaining plate (PRP) may have a plateau region in which the difference between the minimum stress and the maximum stress is less than 10 MPa in a region where the strain is between 0.2 and 0.3.

[0093] The stress in the plateau section may be from 1 MPa to 40 MPa, specifically from 5 MPa to 30 MPa, and more specifically from 10 MPa to 25 MPa. The stress change in the plateau section may be less than or equal to 10 MPa.

[0094] The plateau section stress of the pressure-retaining plate (PRP) can be appropriately selected within the above range depending on the number of battery cells (CELs) and pressure-retaining plates (PRPs) provided in the all-solid-state battery module (MOD).

[0095] If the stress in the plateau region is less than 1 MPa, the stress due to the initial expansion of the all-solid-state battery can be maintained for a certain period of time, but the module (MOD) and the battery cells (CEL) within the module (MOD) may be damaged due to the stress that increases rapidly after the plateau region.

[0096] If the stress in the plateau section exceeds 40 MPa, the magnitude of the maintained stress may be excessive, which may cause damage to the module (MOD) and the battery cells (CEL) within the module (MOD).

[0097] In one embodiment, the pressure-retaining plate (PRP) can stably maintain a stress between 1 MPa and 40 MPa. More specifically, the stress change can be 10 MPa or less in a range where the strain (engineering) of the pressure-retaining plate (PRP) is 0.1 to 0.4, and the stress can be 1 MPa to 40 MPa.

[0098]

[0099] FIGS. 5 to 10 are drawings illustrating a pressure-retaining plate for an all-solid-state battery according to another embodiment. Detailed descriptions of technical features overlapping with those of the pressure-retaining plate for an all-solid-state battery described above with reference to FIGS. 2 and 3 will be omitted, and differences will be described in detail.

[0100] FIG. 5 is a cross-sectional view of a pressure-retaining plate for an all-solid-state battery according to another embodiment of the present invention.

[0101] Referring to FIG. 5, the pressure-retaining plate (PRP) for an all-solid-state battery may include an insulating layer (ISL) surrounding an outer circumferential surface of the pressure-retaining plate (PRP) for an all-solid-state battery described with reference to FIGS. 3 and 4.

[0102] In one embodiment, the thickness of the insulating layer (ISL) may be from 10 μm to 200 μm.

[0103] The insulating layer (ISL) may include an insulating material. For example, the insulating layer (ISL) may include an insulating material such as polyimide (PI) or polyethyleneterephthalate (PET).

[0104] The insulation layer (ISL) can prevent direct electrical connection between battery cells (CELs) and improve module durability. Furthermore, the insulation layer (ISL) can suppress the detachment of the porous layer (POL) due to compression of the pressure-retaining plate (PRP).

[0105]

[0106] Fig. 6 is a cross-sectional view illustrating a pressure-retaining plate for an all-solid-state battery according to another embodiment of the present invention. Fig. 7 is a plan view illustrating a porous layer within the pressure-retaining plate for an all-solid-state battery of Fig. 6.

[0107] Referring to FIGS. 6 and 7, a pressure-retaining plate (PRP) for an all-solid-state battery may include a porous layer (POL) including a first metal foam (MEF1), a second metal foam (MEF2), and a third metal foam (MEF3); a first support layer (SPL1) on an upper surface of the porous layer (POL); and a second support layer (SPL2) on a lower surface of the porous layer (POL). The second metal foam (MEF2) may be adjacent to the first metal foam (MEF1) in a second direction (D2), and the third metal foam (MEF3) may be adjacent to the first metal foam (MEF1) in a first direction (D1). The porous layer (POL) may further include a fourth metal foam (MEF4). The fourth metal form (MEF4) may be adjacent to the second metal form (MEF2) in the first direction (D1) and adjacent to the third metal form (MEF3) in the second direction (D2).

[0108] Each of the first to fourth metal forms (MEFs) can have a width W1 in the first direction.

[0109] Each of the first to fourth metal forms (MEFs) can have a length L1 in the second direction.

[0110] By spacing out the first to fourth metal foams (MEFs), the porous layer (POL) can form voids. The weight of the porous layer can be reduced by the amount of voids, thereby improving the energy density of the all-solid-state battery module (MOD). Furthermore, as air moves through the voids, heat can be effectively dissipated.

[0111] Each of the first to fourth metal forms (MEFs) can have a width W1 in the first direction.

[0112] Each of the first to fourth metal forms (MEFs) can have a length L1 in the second direction.

[0113] The first gap (P1) may be proportional to the size of L1. In one embodiment, the size of P1 with respect to L1 (P1 / L1) may be 0.1 to 0.3. The second gap (P2) may be proportional to the size of W1. In one embodiment, the size of P2 with respect to W1 (P2 / W1) may be 0.1 to 0.3.

[0114] When the pressure-retaining plate (PRP) is compressed in the vertical direction, the metal foams (MEF) can expand in the horizontal direction. For example, when the pressure-retaining plate (PRP) is compressed in the third direction (D3), the metal foams (MEF) can expand in the first and second directions (D1, D2). The first and second gaps (P1, P2) have the above ranges, thereby preventing the metal foams (MEF) from contacting and interfering with each other when expanding in the horizontal direction. By preventing mutual interference between the metal foams (MEF), the compressive force due to the expansion of the all-solid-state battery can be more effectively distributed, thereby maintaining the pressure within the all-solid-state battery module at a constant level.

[0115] In one embodiment of the present invention, the pressure-retaining plate (PRP) for an all-solid-state battery may have a length in the second direction that is greater than a width in the first direction. In addition, the first to fourth metal forms (MEF) may have a length L1 in the second direction that is greater than a width W1 in the first direction. The first gap (P1) and the second gap (P2) have the above-described ratio range, so that the first gap (P1) may be greater than the second gap (P2).

[0116] Although not shown, the pressure-retaining plate (PRP) for an all-solid-state battery may further include an insulating layer (ISL) surrounding the outer circumferential surface of the pressure-retaining plate (PRP) for an all-solid-state battery described with reference to FIG. 5.

[0117]

[0118] Fig. 8 is a cross-sectional view illustrating a pressure-retaining plate for an all-solid-state battery according to another embodiment of the present invention. Fig. 9 is an exploded schematic diagram of the pressure-retaining plate for an all-solid-state battery of Fig. 8. Fig. 10 is a plan view illustrating in more detail the porous layer within the pressure-retaining plate for an all-solid-state battery of Fig. 8.

[0119] Referring to FIGS. 8 to 10, the porous layer (POL) may further include 6th to 16th metal forms (MEF6, MEF7, MEF8, MEF9, MEF10, MEF11, MEF12, MEF13, MEF14, MEF15, MEF16).

[0120] The first metal form (MEF1), the second metal form (MEF2), the ninth metal form (MEF9), and the tenth metal form (MEF10) can be sequentially arranged to be spaced apart in the second direction (D2), and adjacent metal forms can be spaced apart by a first interval (P1).

[0121] The third metal form (MEF3), the fourth metal form (MEF4), the eleventh metal form (MEF11), and the twelfth metal form (MEF12) can be sequentially arranged to be spaced apart in the second direction (D2), and adjacent metal forms can be spaced apart by a first interval (P1).

[0122] The fifth metal form (MEF5), the sixth metal form (MEF6), the thirteenth metal form (MEF13), and the fourteenth metal form (MEF14) can be sequentially arranged to be spaced apart in the second direction (D2), and adjacent metal forms can be spaced apart by a first interval (P1).

[0123] The seventh metal form (MEF7), the eighth metal form (MEF8), the fifteenth metal form (MEF15), and the sixteenth metal form (MEF16) may be sequentially arranged to be spaced apart in the second direction (D2), and adjacent metal forms may be spaced apart by a first interval (P1).

[0124] The first metal form (MEF1), the third metal form (MEF3), the fifth metal form (MEF5), and the seventh metal form (MEF7) can be sequentially arranged to be spaced apart in the first direction (D1), and adjacent metal forms can be spaced apart by a second interval (P2).

[0125] The second metal form (MEF2), the fourth metal form (MEF4), the sixth metal form (MEF6), and the eighth metal form (MEF8) can be sequentially arranged to be spaced apart in the first direction (D1), and adjacent metal forms can be spaced apart by a second interval (P2).

[0126] The ninth metal form (MEF9), the eleventh metal form (MEF11), the thirteenth metal form (MEF13), and the fifteenth metal form (MEF15) can be arranged in sequence spaced apart in the first direction (D1), and adjacent metal forms can be spaced apart at a second interval (P2).

[0127] The tenth metal form (MEF10), the twelfth metal form (MEF12), the fourteenth metal form (MEF14), and the sixteenth metal form (MEF16) can be sequentially arranged to be spaced apart in the first direction (D1), and adjacent metal forms can be spaced apart at a second interval (P2).

[0128] By spacing out the first to sixteenth metal foams (MEFs), the porous layer (POL) can form voids. The weight of the porous layer can be reduced by the amount of voids, thereby improving the energy density of the all-solid-state battery module (MOD). Furthermore, as air moves through the voids, heat can be effectively dissipated.

[0129] Each of the first to sixteenth metal forms (MEFs) can have a width W1 in the first direction.

[0130] Each of the first to sixteenth metal forms (MEFs) can have a length L1 in the second direction.

[0131] The first gap (P1) may be proportional to the size of L1. In one embodiment, the size of P1 with respect to L1 (P1 / L1) may be 0.1 to 0.3. The second gap (P2) may be proportional to the size of L2. In one embodiment, the size of P1 with respect to W1 (P1 / W1) may be 0.1 to 0.3.

[0132] Although not shown, the pressure-retaining plate (PRP) for an all-solid-state battery may further include an insulating layer (ISL) surrounding the outer circumferential surface of the pressure-retaining plate (PRP) for an all-solid-state battery described with reference to FIG. 5.

[0133]

[0134] Hereinafter, embodiments of the present invention will be described in more detail. However, the following embodiments are provided merely to aid understanding of the present invention, and the scope of the present invention is not limited thereby.

[0135]

[0136] Example 1

[0137] (1) Pressure-retaining plate

[0138] Two copper foils measuring 50 mm in length, 25 mm in width, and 100 ㎛ in thickness were prepared.

[0139] A porous copper foam having a density of 3.32 g / cm3 was manufactured by adding 1 part by weight of calcium and 0.5 part by weight of a foaming agent to 100 parts by weight of copper. The manufactured copper foam was cut into pieces of 50 mm in length, 25 mm in width, and 2 mm in thickness, and then placed between two copper foils and pressed to manufacture a plate.

[0140]

[0141] (2) All-solid-state battery module

[0142] Six solid-state batteries were placed inside the solid-state battery module, and the pressure-maintaining plate was placed inside the module so that three solid-state batteries were positioned on the left and right sides, respectively.

[0143]

[0144] Example 2

[0145] (1) Pressure-retaining plate

[0146] Two copper foils measuring 50 mm in length, 25 mm in width, and 100 ㎛ in thickness were prepared.

[0147] Add 1 part by weight of calcium and 0.5 part by weight of foaming agent to 100 parts by weight of copper to obtain a density of 3.32 g / cm 3 A porous copper foam was manufactured. The manufactured copper foam was cut to 22.7 mm in length, 11.3 mm in width, and 2 mm in thickness, to prepare four small copper foams. The small copper foams manufactured on the copper foil were positioned at intervals of 4.6 mm in the length direction and 2.4 mm in the width direction. That is, the small copper foams were positioned such that the size of the first gap (P1, 2.4 mm) with respect to the length (L1, 23.8 mm) of the small copper foam in the first direction (D1) was 0.1 (P1 / L1), and the size of the second gap (P2, 1.2 mm) with respect to the width (W1, 11.9 mm) in the second direction (D2) was 0.1 (P2 / W1).

[0148] A remaining copper foil was placed on top of it and pressure was applied to manufacture a holding plate.

[0149]

[0150] (2) All-solid-state battery module

[0151] Six solid-state batteries were placed inside the solid-state battery module, and pressure-retaining plates were positioned so that three solid-state batteries were positioned on the left and right sides, respectively.

[0152]

[0153] Example 3

[0154] (1) Pressure-retaining plate

[0155] Two copper foils measuring 50 mm in length, 25 mm in width, and 100 ㎛ in thickness were prepared.

[0156] Add 1 part by weight of calcium and 0.5 part by weight of foaming agent to 100 parts by weight of copper to obtain a density of 3.32 g / cm 3 A porous copper foam was manufactured. The manufactured copper foam was cut to 21.7 mm in length, 10.8 mm in width, and 2 mm in thickness to prepare four small copper foams. The four small copper foams manufactured on the copper foil were positioned at 6.6 mm intervals in the length direction and 3.4 mm intervals in the width direction, as shown in Fig. 7. That is, the small copper foams were positioned such that the size of the first interval (P1, 6.6 mm) with respect to the length (L1, 21.7 mm) of the small copper foam in the first direction (D1) was 0.3 (P1 / L1), and the size of the second interval (P2, 3.4 mm) with respect to the width (W1, 10.8 mm) in the second direction (D2) was 0.3 (P2 / W1).

[0157] A remaining copper foil was placed on top of it and pressure was applied to manufacture a holding plate.

[0158]

[0159] (2) All-solid-state battery module

[0160] Six solid-state batteries were placed inside the solid-state battery module, and pressure-retaining plates were positioned so that three solid-state batteries were positioned on the left and right sides, respectively.

[0161]

[0162] Comparative Example 1

[0163] An all-solid-state battery module without a pressure-retaining plate and containing six all-solid-state batteries was manufactured.

[0164]

[0165] Comparative Example 2

[0166] (1) Pressure-retaining plate

[0167] Two copper foils measuring 50 mm in length, 25 mm in width, and 100 ㎛ in thickness were prepared.

[0168] Porous copper foam having a density of 3.32 g / cm3 was manufactured by adding 1 part by weight of calcium and 0.5 part by weight of a foaming agent to 100 parts by weight of copper. The manufactured copper foam was cut to 20 mm in length, 10 mm in width, and 2 mm in thickness, to prepare four small copper foams. The small copper foams manufactured on the copper foil were positioned at intervals of 10 mm in the length direction and 5 mm in the width direction, as shown in Fig. 7. That is, the small copper foams were positioned such that the size of the first gap (P1, 10 mm) with respect to the length (L1, 20 mm) of the small copper foam in the first direction (D1) was 0.5 (P1 / L1), and the size of the second gap (P2, 5 mm) with respect to the width (W1, 10 mm) in the second direction (D2) was 0.5 (P2 / W1). A remaining copper foil was placed on top of it and pressure was applied to manufacture a holding plate.

[0169]

[0170] (2) All-solid-state battery module

[0171] Six solid-state batteries were placed inside the solid-state battery module, and pressure-retaining plates were positioned so that three solid-state batteries were positioned on the left and right sides, respectively.

[0172]

[0173] Evaluation Example 1. Compression Test

[0174] A compressive strength test of the pressure-retaining plate of Example 1 was performed using a universal material testing machine (MTS Model 370.25), and the results are shown in Fig. 11. It can be confirmed that the stress of the plate of Example 1 is maintained constant in the strain range of 0.1 to 0.4. It can be confirmed that the maintained stress is 5 MPa to 30 MPa.

[0175]

[0176] Evaluation Example 2. Swelling force control of an all-solid-state battery module and its effect on improving its lifespan.

[0177] The effect of improving cell life characteristics when the swelling force within the all-solid-state battery module was maintained constant was confirmed.

[0178] Referring to the graph in Figure 12, it can be confirmed that the state of health (SOH) decrease is improved with increasing number of charge / discharge cycles when the swelling force is maintained constant. This confirms that cell life characteristics can be improved by maintaining a constant pressure within the all-solid-state battery module.

[0179]

[0180] Evaluation Example 3. Cell Life Evaluation

[0181] The life characteristics of the all-solid-state batteries in the all-solid-state battery modules according to Examples 1 to 3 and Comparative Examples 1 to 3 were evaluated.

[0182] The battery whose initial capacity was measured was charged to 4.2 V at 30 C and discharged to 2.0 V at 30 C 1000 times, and the remaining capacity % of the 1000th discharge capacity with respect to the initial capacity was measured. The results are shown in Table 1 below.

[0183] Classification Residual Capacity % (4C / 4C cycle) 1000 cycles residual capacity / 1 cycle residual capacity (%) Example 185% Example 288% Example 387% Comparative example 171% Comparative example 281%

[0184] Referring to Table 1, first, it can be confirmed that the cell life characteristics of the battery in the all-solid-state battery module including the pressure-maintaining plate are improved (Example 1 and Comparative Example 1). In addition, it can be confirmed that the cell life characteristics of the battery are improved in the module including the pressure-maintaining plate, in which the ratio of the length gap between the copper foams to the length of the copper foam (P1 / L1) is 0.1 to 0.3 and the ratio of the width gap between the copper foams to the width of the copper foam (P2 / W1) is 0.1 to 0.3 (Examples 2 and 3). On the other hand, it can be confirmed that the cell life characteristics of the battery are significantly reduced in the module including the pressure-maintaining plate, in which the ratio of the length gap between the copper foams to the length of the copper foam (P1 / L1) and the ratio of the width gap between the copper foams to the width of the copper foam (P2 / W1) are 0.5 (Comparative Example 2).

[0185] While embodiments of the present invention have been described with reference to the attached drawings, the present invention may be implemented in other specific forms without altering the technical spirit or essential features thereof. Therefore, it should be understood that the embodiments described above are exemplary in all respects and are not limiting.

Claims

1. A porous layer containing metal foam; A first support layer on the upper surface of the porous layer; and A second support layer is included on the lower surface of the porous layer, A pressure-retaining plate for an all-solid-state battery module, having a plateau section in which the stress change is 10 MPa or less when the strain increases by 0.1 or more in a stress-strain curve, and wherein the stress in the plateau section is 1 MPa to 40 MPa.

2. In paragraph 1, The width of the porous layer in the first direction relative to the width of the first support layer in the first direction is 0.9 to 1.1, A pressure-retaining plate for an all-solid-state battery module, wherein the length of the porous layer in the second direction is 0.9 to 1.1 with respect to the length of the first support layer in the second direction.

3. In the first paragraph, the plateau section has a stress of 1 MPa to 40 MPa in a section where the strain (engineering) is 0.1 to 0.4, and the amount of stress change in the strain section is 10 MPa or less.

4. In paragraph 1, Each of the first and second support layers comprises at least one selected from the group consisting of silver, aluminum, copper, manganese, gold, nickel, titanium, zinc, chromium, brass and steel, A pressure-retaining plate for an all-solid-state battery module, wherein the metal form comprises at least one selected from the group consisting of silver, aluminum, copper, manganese, gold, nickel, titanium, zinc, chromium, brass, and steel.

5. In paragraph 1, The thickness of each of the first and second support layers is 10 ㎛ to 500 ㎛, A pressure-retaining plate for an all-solid-state battery module, wherein the thickness of the porous layer is 0.5 mm to 5 mm.

6. In paragraph 1, A pressure-retaining plate for an all-solid-state battery module, further comprising an insulating layer surrounding its outer surface.

7. In paragraph 6, A pressure-resistant plate for an all-solid-state battery module, wherein the thickness of the insulating layer is 10 ㎛ to 200 ㎛.

8. A porous layer comprising a first metal form, a second metal form, and a third metal form, wherein the second metal form is adjacent to the first metal form in a second direction, and the third metal form is adjacent to the first metal form in a first direction; A first support layer on the upper surface of the porous layer; and Including a second support layer on the lower surface of the above porous layer, The first metal form and the second metal form are spaced apart by a first interval (pitch), The first metal form and the third metal form are spaced apart by a second interval, A pressure-retaining plate for an all-solid-state battery module, wherein the first gap and the second gap are different from each other.

9. In paragraph 8, A pressure-retaining plate for an all-solid-state battery module, wherein the size of the first gap relative to the length in the second direction of the first metal form is 0.1 to 0.

3.

10. In paragraph 8, A pressure-retaining plate for an all-solid-state battery module, wherein the size of the second gap relative to the width of the first metal form in the first direction is 0.1 to 0.

3.

11. In paragraph 8, A pressure-retaining plate for an all-solid-state battery module, wherein the stress in a section where the strain (engineering) is 0.1 to 0.4 in a stress-strain curve is 1 MPa to 40 MPa, and the amount of stress change in the strain section is 10 MPa or less.

12. In paragraph 8, A pressure-retaining plate for an all-solid-state battery module, wherein each of the first and second support layers comprises at least one selected from the group consisting of silver, aluminum, copper, manganese, gold, nickel, titanium, zinc, chromium, brass, and steel.

13. In paragraph 8, A pressure-retaining plate for an all-solid-state battery module, wherein the metal form comprises at least one selected from the group consisting of silver, aluminum, copper, manganese, gold, nickel, titanium, zinc, chromium, brass, and steel.

14. In paragraph 8, The thickness of each of the first and second support layers is 10 ㎛ to 500 ㎛, A pressure-retaining plate for an all-solid-state battery module, wherein the thickness of the porous layer is 0.5 mm to 5 mm.

15. In paragraph 8, A pressure-retaining plate for an all-solid-state battery module, wherein the pressure-retaining plate further includes an insulating layer surrounding an outer circumferential surface of the pressure-retaining plate.

16. In paragraph 8, A pressure-resistant plate for an all-solid-state battery module, wherein the thickness of the insulating layer is 10 ㎛ to 200 ㎛.

17. First battery cell; a second battery cell; and Including a pressure-maintaining plate provided between the first and second battery cells, The above pressure-retaining plate: A porous layer comprising at least one metal foam; A first support layer on the upper surface of the porous layer; and A second support layer is included on the lower surface of the porous layer, An all-solid-state battery module, wherein the pressure-maintaining plate has a plateau section in which the stress change amount is 10 MPa or less when the strain increases by 0.1 or more in the stress-strain curve, and the stress in the plateau section is 1 MPa to 40 MPa.

18. In paragraph 17, Further comprising an end plate provided at one end of the above all-solid-state battery module, An all-solid-state battery module having a bolt fastening hole formed on one side of the end plate.

19. An all-solid-state battery module according to claim 17, wherein each of the first and second battery cells comprises a negative electrode; a solid electrolyte; and a positive electrode. In paragraph 20.17, The above porous layer includes a first metal foam, a second metal foam, and a third metal foam, The second metal form is adjacent to the first metal form in the second direction, and the third metal form is adjacent to the first metal form in the first direction. The first metal form and the second metal form are spaced apart by a first pitch, and the first metal form and the third metal form are spaced apart by a second pitch. The size of the first gap relative to the length of the first metal form in the second direction is 0.1 to 0.3, An all-solid-state battery module, wherein the size of the second gap relative to the width of the first metal form in the first direction is 0.1 to 0.3.

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