Lithium ion conductor and all-solid-state battery containing the same

Abstract

The lithium ion conductor for an all-solid-state battery according to the present disclosure includes an oxide containing lithium (Li), silicon (Si), and boron (B), and has a crystallinity of 25.5% or less.

Description

[Technical field]

[0001] The present disclosure relates to a lithium ion conductor and an all-solid-state battery including the same. [Background technology]

[0002] Recently, the need for smaller portable electronic devices and longer battery life has led to a demand for higher capacity batteries, and the spread of wearable electronic devices has also led to a demand for safer batteries. Therefore, the development of all-solid-state batteries using solid electrolytes instead of liquid electrolytes has been actively pursued.

[0003] Because all-solid-state batteries do not use flammable organic solvents, additional safety circuits can be simplified. Therefore, all-solid-state batteries are expected to be a technology that can manufacture safe batteries with large capacity per volume.

[0004] In addition, sulfide electrolyte (10 -2 S / cm) -4 S / cm~10 -6 Solid-state oxide batteries using oxide electrolytes with a conductivity of 0.1 S / cm exhibit superior stability compared to solid-state sulfide batteries using sulfide electrolytes that react with oxygen and moisture in the air, although they require a high-temperature sintering process.

[0005] Since the stacked oxide all-solid-state battery is a micro-sized battery, it can be mounted on a substrate such as a passive device, and is stable even when exposed to high temperatures during the reflow process required for this. Summary of the Invention [Problem to be solved by the invention]

[0006] One aspect of the present embodiment provides a lithium ion conductor whose ion conductivity can be freely adjusted, which minimizes the amount of decrease in ion conductivity during the manufacturing process of a stacked all-solid-state battery, and which makes it possible to predict the ion conductivity in the stacked all-solid-state battery.

[0007] Another aspect of the present embodiment provides a method for producing the lithium ion conductor.

[0008] Another aspect of the present embodiment provides an all-solid-state battery including the lithium ion conductor.

[0009] However, the objectives to be achieved by the present embodiment are not limited to the above objectives, and may be expanded in various ways without departing from the technical spirit of the embodiment. [Means for solving the problem]

[0010] A lithium ion conductor according to one embodiment includes an oxide containing lithium (Li), silicon (Si) and boron (B), and has a crystallinity of 25.5% or less.

[0011] The crystallinity can be calculated by Equation 1:

[0012] [Formula 1] Crystallinity (%)=[Ic / (Ic+Ia)]×100.

[0013] In formula 1, Ic is the sum of integral values ​​of scattering intensity of crystalline peaks in the X-ray diffraction analysis spectrum of the lithium ion conductor, and Ia is the sum of integral values ​​of scattering intensity of amorphous halos in the X-ray diffraction analysis spectrum of the lithium ion conductor.

[0014] The lithium ion conductor may have a crystallinity of 0% to 12.5%.

[0015] The lithium ion conductor may have a porosity of 1% or less.

[0016] The lithium ion conductor may have a porosity of 0% to 0.5%.

[0017] The lithium ion conductor may contain 45 mol % to 80 mol % of lithium (Li) oxide, 5 mol % to 20 mol % of silicon (Si) oxide, and 15 mol % to 50 mol % of boron (B) oxide, based on the total amount of lithium (Li) oxide, silicon (Si) oxide, and boron (B) oxide contained in the lithium ion conductor.

[0018] The lithium ion conductor may contain 50 mol % to 70 mol % of lithium (Li) oxide based on the total amount of lithium (Li) oxide, silicon (Si) oxide, and boron (B) oxide contained in the lithium ion conductor.

[0019] Lithium ion conductors are Na (sodium), Mg (magnesium), Al (aluminum), P (phosphorus), K (potassium), Ca (calcium), Ti (titanium), V (vanadium), Cr (chromium), Mn (manganese), Fe (iron), Co (cobalt), Ni (nickel), Cu (copper), Zn (zinc), Ga (gallium), Ge (germanium), Se (selenium), Rb (rubidium), S (sulfur), and Y (yttrium). ), Zr (zirconium), Nb (niobium), Mo (molybdenum), Ag (silver), In (indium), Sn (tin), Sb (antimony), Cs (cesium), Ba (barium), Hf (hafnium), Ta (tantalum), W (tungsten), Pb (lead), Bi (bismuth), Au (gold), La (lanthanum), Nd (neodymium), Eu (europium), or combinations thereof.

[0020] The lithium ion conductor may further include additional oxides including P (phosphorus) and Ge (germanium).

[0021] The lithium ion conductor may contain an additional oxide in an amount of 5 mol % or less based on the total amount of lithium (Li) oxide, silicon (Si) oxide, boron (B) oxide, and the additional oxide contained in the lithium ion conductor.

[0022] The lithium ion conductor may contain an additional oxide in an amount of 1 mol % or less based on the total amount of lithium (Li) oxide, silicon (Si) oxide, boron (B) oxide, and the additional oxide contained in the lithium ion conductor.

[0023] A method for producing a lithium ion conductor according to another embodiment includes sintering under pressure an oxide powder including lithium (Li), silicon (Si), and boron (B), wherein the lithium ion conductor has a crystallinity, calculated according to Equation 1, of 25.5% or less.

[0024] [Formula 1] Crystallinity (%)=[Ic / (Ic+Ia)]×100.

[0025] In formula 1, Ic is the sum of integral values ​​of scattering intensity of crystalline peaks in the X-ray diffraction analysis spectrum of the lithium ion conductor, and Ia is the sum of integral values ​​of scattering intensity of amorphous halos in the X-ray diffraction analysis spectrum of the lithium ion conductor.

[0026] The firing can be carried out at a temperature of 300°C to 550°C.

[0027] During the pressurization, a pressure of 1 MPa to 200 MPa can be applied.

[0028] According to another embodiment, an all-solid-state battery includes a solid electrolyte layer, and a positive electrode and a negative electrode sandwiching the solid electrolyte layer. One selected from the solid electrolyte layer, the positive electrode, the negative electrode, and combinations thereof includes a lithium ion conductor including an oxide including lithium (Li), silicon (Si), and boron (B), and the lithium ion conductor has a crystallinity calculated by Equation 1 of 25.5% or less.

[0029] [Formula 1] Crystallinity (%)=[Ic / (Ic+Ia)]×100

[0030] In formula 1, Ic is the sum of integral values ​​of scattering intensity of crystalline peaks in the X-ray diffraction analysis spectrum of the lithium ion conductor, and Ia is the sum of integral values ​​of scattering intensity of amorphous halos in the X-ray diffraction analysis spectrum of the lithium ion conductor.

[0031] The lithium ion conductor may have a porosity of 1% or less.

[0032] The lithium ion conductor may contain 45 mol % to 80 mol % of lithium (Li) oxide, 5 mol % to 20 mol % of silicon (Si) oxide, and 15 mol % to 50 mol % of boron (B) oxide, based on the total amount of lithium (Li) oxide, silicon (Si) oxide, and boron (B) oxide contained in the lithium ion conductor.

[0033] Lithium ion conductors are Na (sodium), Mg (magnesium), Al (aluminum), P (phosphorus), K (potassium), Ca (calcium), Ti (titanium), V (vanadium), Cr (chromium), Mn (manganese), Fe (iron), Co (cobalt), Ni (nickel), Cu (copper), Zn (zinc), Ga (gallium), Ge (germanium), Se (selenium), Rb (rubidium), S (sulfur), and Y (yttrium). ), Zr (zirconium), Nb (niobium), Mo (molybdenum), Ag (silver), In (indium), Sn (tin), Sb (antimony), Cs (cesium), Ba (barium), Hf (hafnium), Ta (tantalum), W (tungsten), Pb (lead), Bi (bismuth), Au (gold), La (lanthanum), Nd (neodymium), Eu (europium), or combinations thereof.

[0034] An all-solid-state battery according to another embodiment includes a stack including a plurality of solid electrolyte layers, a plurality of positive electrodes and negative electrodes arranged alternately with the plurality of solid electrolyte layers sandwiched therebetween, and first and second external electrodes connected to the positive electrodes and negative electrodes, respectively, on one side of the stack and the other side opposite to the one side. One selected from the solid electrolyte layers, the positive electrodes, the negative electrodes, and combinations thereof includes a lithium ion conductor including an oxide including lithium (Li), silicon (Si), and boron (B), and the lithium ion conductor has a crystallinity calculated by Equation 1 of 25.5% or less.

[0035] [Formula 1] Crystallinity (%)=[Ic / (Ic+Ia)]×100

[0036] In formula 1, Ic is the sum of integral values ​​of scattering intensity of crystalline peaks in the X-ray diffraction analysis spectrum of the lithium ion conductor, and Ia is the sum of integral values ​​of scattering intensity of amorphous halos in the X-ray diffraction analysis spectrum of the lithium ion conductor.

[0037] The lithium ion conductor may have a porosity of 1% or less.

[0038] The lithium ion conductor may contain 45 mol % to 80 mol % of lithium (Li) oxide, 5 mol % to 20 mol % of silicon (Si) oxide, and 15 mol % to 50 mol % of boron (B) oxide, based on the total amount of lithium (Li) oxide, silicon (Si) oxide, and boron (B) oxide contained in the lithium ion conductor.

[0039] Lithium ion conductors are Na (sodium), Mg (magnesium), Al (aluminum), P (phosphorus), K (potassium), Ca (calcium), Ti (titanium), V (vanadium), Cr (chromium), Mn (manganese), Fe (iron), Co (cobalt), Ni (nickel), Cu (copper), Zn (zinc), Ga (gallium), Ge (germanium), Se (selenium), Rb (rubidium), S (sulfur), and Y (yttrium). ), Zr (zirconium), Nb (niobium), Mo (molybdenum), Ag (silver), In (indium), Sn (tin), Sb (antimony), Cs (cesium), Ba (barium), Hf (hafnium), Ta (tantalum), W (tungsten), Pb (lead), Bi (bismuth), Au (gold), La (lanthanum), Nd (neodymium), Eu (europium), or combinations thereof. Effect of the Invention

[0040] The lithium ion conductor according to this embodiment has an ionic conductivity that can be freely adjusted, and thus the amount of decrease in ionic conductivity during the manufacturing process of a stacked all-solid-state battery can be minimized, and the ionic conductivity in the stacked all-solid-state battery can be predicted. [Brief description of the drawings]

[0041] [Figure 1] FIG. 1 is a perspective view illustrating a schematic configuration of an all-solid-state battery according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of the all-solid-state battery according to the embodiment shown in FIG. [Diagram 3] FIG. 2 is an exploded perspective view showing a schematic diagram of a unit cell stack structure of the all-solid-state battery according to the embodiment shown in FIG. 1. [Figure 4] This is a scanning electron microscope (SEM) photograph of an ion-milled cross section of a Li2O-B2O3-SiO2 amorphous lithium ion conductor cullet. [Diagram 5] 2 is a scanning electron microscope (SEM) photograph of an ion-milled cross section of a lithium ion conductor pellet according to Example 1. [Figure 6]2 is a scanning electron microscope (SEM) photograph of an ion-milled cross section of a lithium ion conductor pellet according to Comparative Example 1. [Figure 7] 1 is a scanning electron microscope (SEM) photograph of an ion-milled cross section of a lithium ion conductor pellet according to Comparative Example 3. [Figure 8] 1 is a scanning electron microscope (SEM) photograph of an ion-milled cross section of a lithium ion conductor pellet according to Comparative Example 4. [Figure 9] FIG. 1 shows the thermal behavior results of cullet and frit with 50 mol% Li2O by DSC analysis. [Figure 10] FIG. 2 is a diagram showing the results of XRD analysis of the crystal states of a cullet, a frit, and a lithium ion conductor. [Figure 11] FIG. 1 shows the results of SEM-EDAX mapping analysis of a lithium ion conductor. [Figure 12] FIG. 2 is a diagram showing the results of Cole-Cole plots of the lithium ion conductors according to Example 1 and Comparative Example 1. [Figure 13] 2 is a voltage-capacity graph for symmetric cells of the lithium ion conductors according to Example 1 and Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] Various embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The drawings and descriptions should be considered as illustrative in nature and not restrictive. Similar reference numbers indicate similar elements throughout the specification. In addition, the accompanying drawings are provided only to facilitate understanding of the embodiments disclosed herein, and should not be construed as limiting the spirit disclosed herein, and it should be understood that the present invention includes all modifications, equivalents, and alternatives without departing from the scope and spirit of the present invention. In addition, some components in the accompanying drawings are exaggerated, omitted, or shown in a schematic manner, and the size of each component does not completely reflect the actual size.

[0043] Further, unless expressly stated to the contrary, the word "comprise" and variations such as "comprises" and "comprising" are understood to mean the inclusion of the listed elements, but not the exclusion of any other elements.

[0044] In this specification, the term "stacking direction" refers to the direction in which components are stacked in order, or the "thickness direction" perpendicular to the large surface (principal surface) of the sheet-like component, which corresponds to the T-axis direction in the drawings. The term "side direction" refers to the direction extending from the edge of the sheet-like component parallel to the large surface (principal surface), or the "face direction", which corresponds to the L-axis direction in the drawings.

[0045] Various embodiments and modifications will be described in detail below with reference to the drawings.

[0046] In one embodiment, the lithium ion conductor comprises an oxide comprising lithium (Li), silicon (Si) and boron (B). The lithium ion conductor can be used as a battery material, such as a solid electrolyte, an electrode binder, or a coating material, in an all-solid-state battery.

[0047] For example, lithium ion conductors include lithium (Li) oxide (Li 2 O), silicon (Si) oxide (SiO 2 ), boron (B) oxide (B 2 O 3 ).

[0048] The lithium ion conductor may contain 45 mol% to 80 mol% of lithium (Li) oxide, 5 mol% to 20 mol% of silicon (Si) oxide, and 15 mol% to 50 mol% of boron (B) oxide, based on the total amount of the lithium ion conductor, or may contain, for example, 50 mol% to 70 mol% of lithium (Li) oxide, 5 mol% to 15 mol% of silicon (Si) oxide, and 35 mol% to 45 mol% of boron (B) oxide, based on the total amount of the lithium ion conductor. If the content of lithium (Li) oxide is 45 mol% or less, the lithium ion conductivity may be low, and if the content of lithium (Li) oxide is more than 80 mol%, devitrification of the glass may occur. If the silicon (Si) oxide is less than 5 mol%, the obtained lithium ion conductor may be fragile when exposed to a high humidity environment, and if the silicon (Si) oxide is more than 20 mol%, the ion conductivity may be reduced and devitrification may occur. If the boron (B) oxide is less than 15 mol %, the ionic conductivity may decrease and devitrification may occur, and if the boron (B) oxide is more than 50 mol %, the resulting lithium ion conductor may be brittle when exposed to high humidity environments.

[0049] Optionally, the lithium ion conductor may further comprise an additional oxide, for example, Na (sodium), Mg (magnesium), Al (aluminum), P (phosphorus), K (potassium), Ca (calcium), Ti (titanium), V (vanadium), Cr (chromium), Mn (manganese), Fe (iron), Co (cobalt), Ni (nickel), Cu (copper), Zn (zinc), Ga (gallium), Ge (germanium), Se (selenium), Rb (rubidium), S (sulfur), Y (yttrium), Zr (zirconium), Nb (niobium), Mo (molybdenum), or the like. The lithium ion conductor may further include additional oxides including Cr (Ce), Ag (silver), In (indium), Sn (tin), Sb (antimony), Cs (cesium), Ba (barium), Hf (hafnium), Ta (tantalum), W (tungsten), Pb (lead), Bi (bismuth), Au (gold), La (lanthanum), Nd (neodymium), Eu (europium), or combinations thereof, for example, the lithium ion conductor may further include additional oxides including P (phosphorus) and Ge (germanium).

[0050] The lithium ion conductor may contain an additional oxide in an amount of 5 mol % or less, for example 1 mol % or less, based on the total amount of lithium ion conductor. If the content of the additional oxide exceeds 5 mol %, devitrification may occur during glass manufacture or the ionic conductivity may decrease due to secondary crystalline phases formed during sintering.

[0051] The lithium ion conductor may have a crystallinity, calculated by Equation 1, of 25.5% or less, for example, from 0% to 12.5%, or from 0% to 5%.

[0052] [Formula 1] Crystallinity (%)=[Ic / (Ic+Ia)]×100

[0053] In formula 1, Ic is the sum of integral values ​​of scattering intensity of crystalline peaks in the X-ray diffraction analysis spectrum of the lithium ion conductor, and Ia is the sum of integral values ​​of scattering intensity of amorphous halos in the X-ray diffraction analysis spectrum of the lithium ion conductor.

[0054] For example, the crystallinity of lithium ion conductors can be calculated based on a graph obtained by X-ray diffraction spectroscopy. In the X-ray diffraction analysis spectrum, the X-ray wavelength λ, the incident angle θ, and the lattice spacing d have the relationship 2d·sinθ=nλ, which is called the Bragg equation. Therefore, if the incident angle is determined, the lattice spacing d can be obtained. However, in amorphous materials, since random atomic arrangements appear instead of regular atomic arrangements, multiple X-ray diffraction lines do not appear at a specific wavelength, and a wide halo pattern appears in the diffraction angle range of 15° to 35°. In the diffraction angle range of 10° to 60°, a diffuse halo pattern appears instead of a peak at a specific angle, which determines an amorphous material with a crystallinity of 0%. However, the surface of the lithium ion conductor exposed to X-rays should not contain any contaminants other than organic matter. The results can be highly reliable only when the measurement is performed under conditions without factors that affect the diffraction pattern. If crystals are present in the lithium ion conductor, one or more crystal peaks will be present in the corresponding measurement diffraction angle range. Here, the higher the crystallinity, the smaller the halo region, and when the crystallinity is 100%, the halo region disappears. When crystals and amorphous matter are mixed, the crystallinity is obtained by calculating the relative ratio of the area of ​​the halo region to the area of ​​the crystalline peak region in a graph of intensity and diffraction angle range.

[0055] The crystallinity of the lithium ion conductor can be adjusted, for example, by changing the content of lithium (Li) oxide, and as the content of lithium (Li) oxide increases, the crystallization temperature gradually decreases overall, thereby increasing the crystallinity. In this way, the crystallinity of the lithium ion conductor can be controlled to freely adjust the ion conductivity.

[0056] Lithium ion conductors with a crystallinity greater than 25.5% may have acceptable ionic conductivity, and for example, crystallinity greater than 50.0% may result in loss of ionic conductivity but insulator-like properties.

[0057] The lithium ion conductor may have a porosity of 1% or less, or for example from 0% to 0.5%.

[0058] The porosity of lithium ion conductors can be measured by taking scanning electron microscope (SEM) pictures. For example, a sample is prepared by etching the surface of the lithium ion conductor very smoothly, and then a scanning electron microscope picture of the surface is taken. Surface etching of lithium ion conductors may be performed using fine sandpaper, but this can damage the sample and distort the information, so ultra-precise etching equipment such as plasma etching, reactive ion etching, etc. can be used. Scanning electron microscope pictures are taken at 30K or 50K magnification so that the pores of the lithium ion conductor are visible, and the porosity can be measured in an image that is, for example, 40 μm wide by 30 μm long.

[0059] Here, when the lithium ion conductor has pores, the pores appear dark in the scanning electron microscope photograph. An image program such as an electron probe microanalyzer (EPMA) can be used to calculate the ratio of bright and dark areas, where the electron probe microanalyzer (EPMA) may include an EDS (energy dispersive spectrometer), a WDS (wavelength dispersive spectrometer), or the like. Here, it is assumed that the dark areas are pores, and the bright areas are, in contrast, lithium ion conductors. For example, the porosity of the lithium ion conductor may be binarized using a scanning electron microscope image using an EDS or the like, and the area ratio of the area of ​​the area with different contrast to the entire area to be measured may be calculated. Also, measurements may be performed at at least 3, 5, or 10 different points or on a cross section, and the arithmetic average of the measurements obtained therefrom may be calculated.

[0060] When the porosity of the lithium ion conductor is 1% or less, the density of the lithium ion conductor increases, minimizing the decrease in ion conductivity during the manufacturing process of the stacked all-solid-state battery, and therefore the ion conductivity of the stacked all-solid-state battery can also be predicted.

[0061] When the porosity of a lithium-ion conductor exceeds 1%, it may exhibit a decrease in ionic conductivity and may become vulnerable to the external environment. The greater the porosity, the greater the lithium-ion conductor may exhibit a decrease in ionic conductivity and may become more vulnerable to the external environment.

[0062] A method for producing a lithium ion conductor according to another embodiment includes sintering an oxide powder containing lithium (Li), silicon (Si) and boron (B) under pressure.

[0063] First, several types of amorphous materials are mixed as raw materials.

[0064] The amorphous material may include network forming oxides (network formers: NWFs), modifying oxides (network modifiers), and intermediate oxides may be used as needed.

[0065] The network-forming oxides themselves may be vitrified. The modifying oxides are not themselves amorphous, but may be amorphized within the network formed by the network oxides, i.e., modify the network.

[0066] The network forming oxide is SiO 2 and B. 2 O 3 The modified oxide may include Li 2 It may contain O.

[0067] The intermediate oxide is a raw material having properties between those of the network-forming oxide and the modifying oxide, and has the effect of lowering the thermal expansion coefficient, for example, among the thermal properties of glass.

[0068] Examples of intermediate oxides include Na (sodium), Mg (magnesium), Al (aluminum), P (phosphorus), K (potassium), Ca (calcium), Ti (titanium), V (vanadium), Cr (chromium), Mn (manganese), Fe (iron), Co (cobalt), Ni (nickel), Cu (copper), Zn (zinc), Ga (gallium), Ge (germanium), Se (selenium), Rb (rubidium), S (sulfur), Y (yttrium), and Zr (chromium). The oxides may include oxides including Zr (zirconium), Nb (niobium), Mo (molybdenum), Ag (silver), In (indium), Sn (tin), Sb (antimony), Cs (cesium), Ba (barium), Hf (hafnium), Ta (tantalum), W (tungsten), Pb (lead), Bi (bismuth), Au (gold), La (lanthanum), Nd (neodymium), Eu (europium), or combinations thereof.

[0069] Li 2 O is Li 2 O, SiO 2 and B. 2 O 3 SiO may be contained in an amount of 45 mol % to 80 mol %, or 50 mol % to 70 mol %, based on the total amount of SiO. 2 Li 2 O, SiO 2 and B. 2 O 3 It may be contained in an amount of 5 mol % to 20 mol % based on the total amount of B. 2 O 3 Li 2 O, SiO 2 and B. 2 O 3 It may be contained in an amount of 15 mol % to 50 mol % based on the total amount of the above.

[0070] When an intermediate oxide is used as the amorphous material, the intermediate oxide may be used in an amount of 5 mol % or less based on the total amount of the network-forming oxides, the modifier oxides and the intermediate oxides.

[0071] The precursor (glass) of the lithium ion conductor can be produced by vitrifying the raw material. Examples of the method for vitrifying the raw material include a method of melting the raw material to obtain a molten liquid and cooling the molten liquid, a method of pressing the molten liquid onto a metal plate or the like, a method of dropping into mercury, a method using a strip furnace, a splat quenching method, a rolling (single, twin) method, and other methods such as mechanical milling, a sol-gel method, a vapor deposition method, a sputtering method, a laser ablation method, a PLD (pulsed laser deposition) method, and a plasma method.

[0072] The lithium ion conductor can be produced by calcining a precursor of the lithium ion conductor under pressure. At this time, the calcination may be carried out at a temperature of 300° C. to 550° C., for example, 400° C. to 500° C., and the pressure may be 1 MPa to 200 MPa, for example, 1 MPa to 50 MPa.

[0073] The lithium ion conductor produced by sintering a precursor of the lithium ion conductor under pressure may have a crystallinity of 25.5% or less and a porosity of 1% or less.

[0074] Alternatively, the lithium ion conductor may be powdered by a mechanochemical method or the like.

[0075] An all-solid-state battery according to another embodiment includes a solid electrolyte layer, and a positive electrode and a negative electrode disposed with the solid electrolyte layer sandwiched therebetween, and any one selected from the solid electrolyte layer, the positive electrode, the negative electrode, and combinations thereof includes the lithium ion conductor according to one embodiment.

[0076] Fig. 1 is a perspective view that shows a schematic diagram of an all-solid-state battery according to another embodiment, Fig. 2 is a cross-sectional view of the all-solid-state battery according to the embodiment shown in Fig. 1, and Fig. 3 is an exploded perspective view that shows a schematic diagram of a unit cell stack structure of the all-solid-state battery according to the embodiment shown in Fig. 1. Hereinafter, the all-solid-state battery will be described in detail with reference to Figs. 1 to 3.

[0077] The all-solid-state battery 100 may have, for example, a substantially hexahedral shape.

[0078] In this embodiment, for convenience of explanation, in the all-solid-state battery 100, both sides facing each other in the thickness direction (T-axis direction) are defined as the first and second sides, and both sides connected to the first and second sides and facing each other in the length direction (L-axis direction) are defined as the third and fourth sides. For example, the first and second sides of the all-solid-state battery 100 can be connected to the third and fourth sides.

[0079] The all-solid-state battery 100 according to this embodiment includes electrode layers 120, 140 and a solid electrolyte layer 130 adjacent to the electrode layers 120, 140 in the stacking direction. The electrode layers 120, 140 may include a positive electrode layer 120 and a negative electrode layer 140, and may basically include current collectors 123, 143 and active material layers 121, 122, 141, 142 applied to at least one surface of the current collectors 123, 143.

[0080] The positive electrode layer 120 may be formed by applying the positive electrode active material layers 121 and 122 to at least one surface of the positive electrode collector 123, and the negative electrode layer 140 may be formed by applying the negative electrode active material layers 141 and 142 to at least one surface of the negative electrode collector 143. For example, the topmost electrode layer in the stacking direction may be formed by applying the positive electrode active material layer 122 to one surface of the positive electrode collector 123, and the bottommost electrode layer may be formed by applying the negative electrode active material layer 141 to one surface of the negative electrode collector 143. In addition, the electrode layer between the topmost end and the bottommost end is formed by applying the positive electrode active material layers 121 and 122 to both surfaces of the positive electrode collector 123, or by applying the negative electrode active material layers 141 and 142 to both surfaces of the negative electrode collector 143.

[0081] The positive electrode active material layers 121 and 122 may contain a positive electrode active material and, optionally, a solid electrolyte. The positive electrode active material layers 121 and 122 may further contain, optionally, additives such as a binder and a conductive agent.

[0082] For example, the positive electrode active material is not particularly limited as long as it can ensure a sufficient capacity of the all-solid-state battery 100. For example, the positive electrode active material may include lithium cobalt oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium iron phosphate, lithium manganese oxide, or a combination thereof.

[0083] For example, the positive electrode active material may be a compound represented by the following chemical formula: Li a A 1-b M b D 2 (where 0.90≦a≦1.8, 0≦b≦0.5);Li a E l-b M b O 2-c D c (where 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05);LiE 2-b M b O 4-c D c (where 0≦b≦0.5, 0≦c≦0.05);Li a Ni 1-b-c Co b M c D α (where 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05, 0<α≦2);Li a Ni 1-b-c Co b M c O 2-α X α (where 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05, 0<α<2);Li a Ni 1-b-c CO b M c O 2-α X 2 (where 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05, 0<α<2);Li a Ni 1-b-c Mn b M c D α (where 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05, 0<α≦2);Li a Ni1-b-c Mn b M c O 2-α X α (where 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05, 0<α<2);Li a Ni 1-b-c Mn b M c O 2-α X 2 (where 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05, 0<α<2);Li a Ni b E c G d O 2 (however 、 0.90≦a≦1.8, 0≦b≦0.9, 0≦c≦0.5, 0.001≦d≦0.1);Li a Ni b Co c Mn d G e O 2 (where 0.90≦a≦1.8, 0≦b≦0.9, 0≦c≦0.5, 0≦d≦0.5, 0.001≦e≦0.1);Li a NiG b O 2 (where 0.90≦a≦1.8, 0.001≦b≦0.1);Li a CoG b O 2 (where 0.90≦a≦1.8, 0.001≦b≦0.1);Li a MnG b O 2 (where 0.90≦a≦1.8, 0.001≦b≦0.1);Li a Mn 2 G b O 4 (where 0.90≦a≦1.8, 0.001≦b≦0.1);QO 2 ;QS 2 ;LiQS 2 ;V 2 O 5 ;LiV 2 O 2 ;LiRO 2 ;LiNiVO 4 Li (3-f) J 2 (PO4 ) 3 (0≦f≦2);Li (3-f) Fe 2 (PO 4 ) 3 (where 0≦f≦2); and LiFePO 4 In the above chemical formula, A is Ni, Co, or Mn; M is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, or a rare earth element; D is O, F, S, or P; E is Co or Mn; X is F, S, or P; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, or V; Q is Ti, Mo, or Mn; R is Cr, V, Fe, Sc, or Y; and J is V, Cr, Mn, Co, Ni, or Cu.

[0084] The positive electrode active material is LiCoO 2 , LiMn x O 2x (where x=1 or 2), LiNi 1-x Mn x O 2x (where 0 <x<1)、LiNi 1-x-y Co x Mn y O 2 (where 0≦x≦0.5 and 0≦y≦0.5), LiFePO 4 , TiS 2 , FeS 2 , TiS 3 , or FeS 3 may be also possible.

[0085] According to one embodiment, the solid electrolyte may include a lithium ion conductor. The content of the solid electrolyte may be 0.1 parts by weight or more, 1 part by weight or more, or 10 parts by weight or more, and may be 80 parts by weight or less, 60 parts by weight or less, or 50 parts by weight or less, relative to 100 parts by weight of the total amount of the positive electrode active material.

[0086] The conductive agent is not particularly limited as long as it has conductivity without causing a chemical change in the all-solid-state battery 100. Examples of the conductive agent include: graphite such as natural graphite and artificial graphite; carbon-based substances such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and summer black; conductive fibers such as carbon fibers and metal fibers; fluorinated carbon; metal powders such as aluminum and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; and conductive materials such as polyphenylene derivatives.

[0087] The content of the conductive agent may be 1 to 10 parts by weight, for example, 2 to 5 parts by weight, relative to 100 parts by weight of the positive electrode active material. If the content of the conductive agent is within the above range, the finally obtained electrode can have excellent conductive properties.

[0088] A binder may be used to improve the binding force between the active material and the conductive agent. Examples of the binder include polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, fluororubber, and various copolymers.

[0089] The content of the binder may be 1 part by weight to 50 parts by weight, for example 2 parts by weight to 5 parts by weight, relative to 100 parts by weight of the total positive electrode active material. When the content of the binder satisfies the above range, the active material layer has high adhesive strength.

[0090] A porous material such as a mesh or a mesh-like material can be used as the positive electrode current collector 123, and a porous metal plate such as stainless steel, nickel, aluminum, etc. can also be used. The positive electrode current collector 123 may also be coated with an oxidation-resistant metal or alloy film to prevent oxidation.

[0091] The negative electrode active material layers 141 and 142 may contain a negative electrode active material and, optionally, a solid electrolyte. Further, the negative electrode active material layers 141 and 142 may further contain, optionally, additives such as a binder and a conductive agent.

[0092] The negative electrode active material may be a carbon-based material, silicon, silicon oxide, silicon-based alloy, silicon-carbon-based material composite, tin, tin-based alloy, tin-carbon composite, metal oxide, or a combination thereof, and may contain lithium metal and / or a lithium metal alloy.

[0093] The lithium metal alloy may contain lithium and a metal / semimetal alloyable with lithium. For example, the metal / semimetal alloyable with lithium is Si, Sn, Al, Ge, Pb, Bi, Sb, Si-Y alloy (Y is an alkali metal, alkaline earth metal, Group 13-16 element, transition metal, rare earth element, or a combination thereof, and Si is not included), Sn-Y alloy (Y is an alkali metal, alkaline earth metal, Group 13-16 element, transition metal, or lithium titanate (Li 4 Ti 5 O 12 ) and other transition metal oxides, rare earth elements, or a combination thereof, and Sn is not included), or M n O x (0 < x ≤ 2) may be included.

[0094] The element Y may be Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Tc, Re, Bh, Fe, Pb, Ru, Os, Hs, Rh, Ir, Pd, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, Sn, In, Tl, Ge, P, As, Sb, Bi, S, Se, Te, Po, or a combination thereof.

[0095] Further, the oxides of the metal / semimetal alloyable with lithium are lithium titanate, vanadium oxide, lithium vanadate, SnO 2 , SiO xIt may be, for example, (0 < x < 2). For example, the negative electrode active material can contain one or more elements selected from the elements of Groups 13 to 16 of the periodic table. For example, the negative electrode active material can contain one or more elements selected from the group consisting of Si, Ge, and Sn.

[0096] The carbon-based material may be crystalline carbon, amorphous carbon, or a mixture thereof. The crystalline carbon may include graphite such as natural graphite or artificial graphite in an amorphous, plate-like, flaky, spherical, or fibrous form. Also, the amorphous carbon may include soft carbon (low-temperature calcined carbon) or hard carbon, mesophase pitch carbonization products, calcined coke, graphene, carbon black, fullerene soot, carbon nanotubes, carbon fibers, and the like.

[0097] Silicon may be Si, SiO x (0 < x < 2, for example, 0.5 to 1.5), Sn, SnO 2 It may be a silicon-containing metal alloy, or a mixture thereof. The silicon-containing metal alloy may include, for example, silicon and one or more of Al, Sn, Ag, Fe, Bi, Mg, Zn, In, Ge, Pb, and Ti.

[0098] The solid electrolyte can contain a lithium ion conductor according to one embodiment. The content of the solid electrolyte may be 0.1 part by weight or more, 1 part by weight or more, 10 parts by weight or less, 80 parts by weight or less, 60 parts by weight or less, 50 parts by weight or less with respect to 100 parts by weight of the total amount of the negative electrode active material.

[0099] The negative electrode active material layer may selectively contain a conductive agent and a binder described for the positive electrode active material layer.

[0100] The negative electrode current collector 143 may be a mesh or a porous body in a mesh shape, or a porous metal plate such as stainless steel, nickel, or aluminum. Also, the negative electrode current collector 143 may be coated with an oxidation-resistant metal or alloy film to prevent oxidation.

[0101] The solid electrolyte layer 130 may be interposed and laminated between the positive electrode layer 120 and the negative electrode layer 140. Therefore, the solid electrolyte layer 130 may be disposed adjacent to the positive electrode active material layers 121 and 122 of the positive electrode layer 120 and the negative electrode active material layers 141 and 142 of the negative electrode layer 140 in the lamination direction. Therefore, in the all-solid-state battery 100, a plurality of positive electrode layers 120 and a plurality of negative electrode layers 140 may be alternately arranged, and a plurality of solid electrolyte layers 130 may be interposed and laminated therebetween. The all-solid-state battery 100 is a laminated all-solid-state battery 100 manufactured by alternately laminating a plurality of positive electrode layers 120 and negative electrode layers 140, interposing a plurality of solid electrolyte layers 130 therebetween to form a cell stack, and firing them all at once.

[0102] The solid electrolyte layer 130 can include an inorganic solid electrolyte including an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or a combination thereof. For example, the solid electrolyte layer 130 can include a lithium ion conductor according to one embodiment.

[0103] The oxide-based solid electrolyte may be a garnet type, NASICON type, LISICON type, perovskite type, LiPON type, or amorphous (glass) electrolyte.

[0104] Examples of the garnet-based solid electrolyte include lithium lanthanum zirconium oxide (LLZO) represented by Li 7 La 3 Zr 2 O 12 and the like. Examples of the NASICON-based solid electrolyte include lithium aluminum titanium phosphate (LATP) of Li a La b Zr c O 12 where 0 < x < 1, (where Ti is Li 1+x Al x Ti 2-x (PO 4 ) 3 (0 < x < 1), and (where Ti is Li 1+x Al x M 2-x (PO 4 ) 3(LAMP) (where 0 < x < 2 and M is Zr, Ti, or Ge), Li introduced into the compound 1+x Al x Ge 2-x (PO 4 ) 3 Lithium aluminum germanium phosphate (LAGP) represented by 0 < x < 1, for example, Li with excess lithium introduced 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 and / or Lithium zirconium phosphate (LZP) of LiZr 2 (PO 4 ) 3 is mentioned.

[0105] Furthermore, as the LISICON-based solid electrolyte, a solid solution oxide represented by xLi 3 AO 4 -(1 - x)Li 4 BO 4 (where A is P, As, or V, and B is Si, Ge, or Ti), for example, Li 4 Zn(GeO 4 ) 4 , Li 10 GeP 2 O 12 (LGPO), Li 3.5 Si 0.5 P 0.5 O 4 , or Li 10.42 Si(Ge) 1.5 P 1.5 Cl 0.08 O 11.92 , or Li 4-x M 1-y M’ y S 4 (where M is Si or Ge, and M’ is P, Al, Zn, or Ga), for example, Li 2 S - P 2 S 5 , Li 2 S - SiS 2 , Li 2 S - SiS 2 -P 2 S 5 , or Li2 S-GeS 2 can be mentioned.

[0106] As for the perovskite-type solid electrolyte, Li 3x La 2 / 3-x □ 1 / 3-2x TiO 3 (0 < x < 0.16, □: vacancy) lithium lanthanum titanate (LLTO) represented by, for example, Li 1 / 8 La 5 / 8 TiO 3 can be mentioned. As for the LiPON-based solid electrolyte, Li 2.8 PO 3.3 N 0.46 and other lithium phosphate nitrides can be mentioned.

[0107] Examples of the amorphous electrolyte include Li 2 O - B 2 O 3 - SiO 2 , Li 2 O - B 2 O 3 - P 2 O 5 , Li 3 BO 3 - Li 2 SO 4 , or Li 3 BO 3 - Li 2 CO 3 can be mentioned.

[0108] The sulfide-based solid electrolyte may contain sulfur atoms in the electrolyte component, is not limited to specific components, and may include one or more of a crystalline solid electrolyte, an amorphous solid electrolyte (glass solid electrolyte), or a glass-ceramics solid electrolyte.

[0109] For example, as the sulfide-based solid electrolyte, LPS-type sulfides containing sulfur and phosphorus (for example, Li 2 S - P 2 S 5 ), for example, thio-LISICON-based compounds, for example, Li 4-x Ge 1-x P x S 4(x is 0.1 to 2, or x is 3 / 4, or 2 / 3), Li 10±1 MP 2 X 12 (M is Ge, Si, Sn, or Al, and X is S or Se), Li 3.833 Sn 0.833 As 0.166 S 4 , Li 4 SnS 4 , Li 3.25 Ge 0.25 P 0.75 S 4 , Li 2 SP 2 S 5 , B 2 S 3 -Li 2 S, xLi 2 S-100-xP 2 S 5 (x is 70~80), Li 2 S-SiS 2 -Li 3 N, Li 2 SP 2 S 5 - LiI, Li 2 S-SiS 2 - LiI, Li 2 S.B. 2 S 3 - LiI, Li 10 SnP 2 S 12 , Li 3.25 Ge 0.25 P 0.75 S 4 Examples include:

[0110] The ionic conductivity of solid electrolytes is 1×10 -6 The ionic conductivity may be measured at a temperature of 25° C. The ionic conductivity may be greater than or equal to 1×10 -6 S / cm or more, 2×10 -6 S / cm or more, 3×10 -6 S / cm or more, 4×10 -6 S / cm or more, 5×10 -6 S / cm or more, 1×10 -3S / cm or more, but there is no particular upper limit. When a solid electrolyte that satisfies this ion conductivity range is used, the all-solid-state battery 100 may exhibit high output.

[0111] The margin insulating layer 150 may be disposed along edges of the positive electrode layer 120 and the negative electrode layer 140. The margin insulating layer 150 may be disposed on the solid electrolyte layer 130 and formed laterally adjacent to edges of the positive electrode active material layers 121, 122 or the negative electrode active material layers 141, 142. Thus, the margin insulating layer 150 may be disposed on the same layer as the positive electrode layer 120 and the negative electrode layer 140.

[0112] The margin insulating layer 150 has an ionic conductivity of 1.0×10 -10 S / cm or less, or 1.0 x 10 -6 S / For example, the insulating material may include the above-mentioned solid electrolyte material or resin.

[0113] For example, the insulating material may be a polyolefin, such as polyethylene or polypropylene, a polyester, such as polyethylene terephthalate (PET), a polyurethane, or a polyimide.

[0114] Additionally, the margin insulating layer 150 may include an inorganic solid electrolyte, including an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or a combination thereof, used in the solid electrolyte layer 130. However, the material included in the margin insulating layer 150 is not limited thereto, and may include various materials.

[0115] The positive electrode layer 120, the solid electrolyte layer 130, the negative electrode layer 140, and the margin insulation layer 150 can be stacked as described above to form a cell stack for the all-solid-state battery 100.

[0116] A protective layer made of an insulating material may be formed on the upper and lower ends of the cell stack of the all-solid-state battery 100.

[0117] Furthermore, terminals of the positive electrode current collector 123 and the negative electrode current collector 143 are exposed on both sides of the cell stack of the all-solid-state battery 100, and the external electrodes 112, 114 are connected to the exposed terminals and combined. In other words, the external electrodes 112, 114 are connected to the terminal of the positive electrode current collector 123 to form a positive electrode, and are connected to the terminal of the negative electrode current collector 143 to form a negative electrode. When the terminals of the positive electrode current collector 123 and the negative electrode current collector 143 are configured to face in opposite directions to each other, the external electrodes 112, 114 may also be disposed on both sides, respectively.

[0118] The outer electrodes 112 and 114 may include conductive metals and glasses.

[0119] Examples of conductive metals include copper (Cu), nickel (Ni), tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), tungsten (W), titanium (Ti), lead (Pb), or alloys thereof.

[0120] The glass component contained in the first and second external electrodes 112, 114 may have a composition in which oxides are mixed. Examples of the glass component include silicon oxide, boron oxide, aluminum oxide, transition metal oxide, alkali metal oxide, alkaline earth metal oxide, or a combination thereof. Here, the transition metal may be selected from zinc (Zn), titanium (Ti), copper (Cu), vanadium (V), manganese (Mn), iron (Fe), and nickel (Ni), the alkali metal may be selected from lithium (Li), sodium (Na), and potassium (K), and the alkaline earth metal may be selected from magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba).

[0121] There is no particular limitation on the method of forming the first and second external electrodes 112, 114. For example, the method may include immersing the cell stack in a conductive paste containing a conductive metal and glass, or screen printing or gravure printing the conductive paste onto the surface of the cell stack. Also, various methods can be used, such as a method of applying the conductive paste onto the surface of the cell stack, or a method of transferring a dry film obtained by drying the conductive paste onto the cell stack.

[0122] Specific examples of the present invention will be described below. However, the following examples are intended to specifically illustrate or explain the present invention, and the scope of the present invention is not limited to these examples.

[0123] [Production Example]

[0124] (Production Example 1: Production of Lithium Ion Conductor Cullet)

[0125] Lithium oxide (Li 2 O), boron oxide (B 2 O 3 ), and silica (SiO 2 ) is used as a raw material to produce lithium borosilicate glass. Optionally, phosphorus oxide (P 2 O 5 ), germanium oxide (GeO 2 ) are added thereto as additional oxides in a total amount of about 5 mol %.

[0126] The raw materials are mixed uniformly, placed in a platinum crucible, and melted at 900℃ to 1100℃. The molten glass liquid is quenched in an environment below the crystallization temperature to obtain colorless and transparent cullet. The cullet is crushed through a coarse crushing and fine crushing process to obtain frit. The frit has an average particle size of 1.0μm to 10μm, which can be adjusted as needed.

[0127] Manufactured Li 2 Alumni 2 O 3 -SiO 2A scanning electron microscope (SEM) photograph of the ion milled cross section of the amorphous lithium ion conductor cullet was taken and is shown in FIG.

[0128] (Production Example 2: Production of lithium ion conductor pellets)

[0129] The prepared glass frit is processed into circular pellets for evaluation. Here, sintering is performed using a pressure sintering device to reduce the porosity. Here, any pressure within the range of 1 MPa to 200 MPa that reduces the porosity to 1% or less can be applied under any conditions. The temperature can be set within an appropriate range by thermal analysis (Tg-DTA or DSC) depending on the composition of the glass. To produce a lithium ion conductor with a crystallinity of 25.5% or less, sintering is performed below the crystallization temperature. The crystallization temperature is determined by the ratio of the glass components and is set at a temperature below the crystallization temperature of Li. 2 O and B 2 O 3 The higher the content of SiO 2 The higher the content of, the higher the crystallization temperature tends to be. However, the crystallization temperature may vary depending on the type of added oxide. As shown in Tables 1 and 2 below, the pressing conditions and sintering conditions were adjusted to produce lithium ion conductors of the examples and comparative examples.

[0130] Scanning electron microscope (SEM) photographs of ion milled cross sections of the lithium ion conductor pellets of Example 1 and Comparative Examples 1, 3 and 4 are shown in FIGS. 5 to 8, respectively.

[0131] [Experimental Example]

[0132] (Experimental Example 1: Synthesis and Evaluation of Lithium Ion Conductors)

[0133] FIG. 9 shows the results of the DSC analysis of 50 mol % Li 2 9 shows the results of the thermal behavior of cullet and frit containing O. Referring to FIG. 9, the lithium ion conductor is densified under the limiting condition between Tg and Tx.

[0134] Figure 10 shows the results of XRD analysis of the cullet, frit, and crystalline lithium ion conductors. Referring to Figure 10, it can be seen that unlike the amorphous cullet and frit, the lithium ion conductors exhibit a crystallinity of 25.5% or less.

[0135] Figure 11 shows the SEM-EDAX mapping analysis result of the lithium ion conductor. Referring to Figure 11, in the manufactured lithium ion conductor, the seed grows into a crystal containing Si, which is consistent with the XRD result.

[0136] (Experimental Example 2: Evaluation of electrochemical properties of lithium ion conductors)

[0137] The lithium ion conductors are evaluated for lithium ion conductivity capability by performing electrochemical analysis.

[0138] Fig. 12 shows the Cole-Cole plot results of the lithium ion conductors according to Example 1 and Comparative Example 1. Referring to Fig. 12, the lithium ion conductor of Example 1 exhibits superior ion conductivity compared to the lithium ion conductor of Comparative Example 1. In addition, the lithium ion conductor of Comparative Example 1, in which crystallization occurs, exhibits a resistance that is increased by two times.

[0139] 13 is a voltage-capacity graph in symmetrical cells of the lithium ion conductors according to Example 1 and Comparative Example 1. Referring to FIG. 13, the lithium ion conductor of Example 1 has a capacity of 10 μA cm -2 to 1mAh cm -2 When reacted for up to 200 hours (over 200 hours), an overvoltage of 30 mV was observed, ensuring electrochemical properties close to those of a liquid electrolyte. In contrast, the lithium ion conductor of Comparative Example 1 exhibited overall reduced performance due to crystallization.

[0140] (Experimental Example 3: Analysis of the characteristics of lithium ion conductors)

[0141] Platinum or gold elements are applied to both sides of a lithium ion conductor pellet manufactured under high temperature and pressure and having a high transparency of 100 nm or more. At this time, both sides must not be electrically conductive. Using an electrochemical impedance analyzer that determines the ionic conductivity taking into account the area and thickness of the lithium ion conductor, a Cole-Cole plot was obtained in the frequency range of 1 MHz to 0.01 Hz, and the results are shown in Tables 1 and 2.

[0142] [Table 1] [Table 2]

[0143] With reference to Tables 1 and 2, the lithium ion conductor having a crystallinity of 25.5% or less has a crystallinity of 1.0×10 -7 It exhibits ionic conductivity of more than S / cm.

[0144] While the present invention has been described in connection with what are presently considered to be practical embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but rather, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. [Industrial Applicability]

[0145] The present disclosure relates to a lithium ion conductor whose ion conductivity can be freely adjusted, which minimizes the amount of decrease in ion conductivity during the manufacturing process of a laminated all-solid-state battery, and which therefore enables prediction of ion conductivity in the laminated all-solid-state battery, and an all-solid-state battery including the same. [Explanation of symbols]

[0146] 100: All-solid-state battery 112, 114: External electrode 120: Positive electrode layer 121, 122: Positive electrode active material layer 123: Positive electrode current collector 130: Solid electrolyte layer 140: Negative electrode layer 141, 142: Negative electrode active material layer 143:Negative electrode current collector 150: Margin insulation layer

Claims

1. A lithium ion conductor for an all-solid-state battery, comprising an oxide containing lithium (Li), silicon (Si) and boron (B), The lithium ion conductor for an all-solid-state battery has a crystallinity of 25.5% or less.

2. The crystallinity is calculated according to Equation 1: The lithium ion conductor for an all-solid-state battery according to claim 1: [Formula 1] Crystallinity (%) = [Ic / (Ic+Ia)] x 100, In the formula 1, Ic is the sum of integral values ​​of scattering intensity of crystal peaks in the X-ray diffraction analysis spectrum of the lithium ion conductor, Ia is the sum of integral values ​​of scattering intensity of amorphous halos in the X-ray diffraction analysis spectrum of the lithium ion conductor.

3. The lithium ion conductor has a crystallinity of 0% to 12.5%. The lithium ion conductor for an all-solid-state battery according to claim 1 .

4. The lithium ion conductor has a porosity of 1% or less. The lithium ion conductor for an all-solid-state battery according to claim 1 .

5. the lithium ion conductor has a porosity of 0% to 0.5%; The lithium ion conductor for an all-solid-state battery according to claim 4.

6. The lithium ion conductor contains 45 mol % to 80 mol % of lithium (Li) oxide, 5 mol % to 20 mol % of silicon (Si) oxide, and 15 mol % to 50 mol % of boron (B) oxide based on the total amount of lithium (Li) oxide, silicon (Si) oxide, and boron (B) oxide contained in the lithium ion conductor. The lithium ion conductor for an all-solid-state battery according to claim 1 .

7. The lithium ion conductor contains 50 mol % to 70 mol % of lithium (Li) oxide based on the total amount of lithium (Li) oxide, silicon (Si) oxide, and boron (B) oxide contained in the lithium ion conductor. The lithium ion conductor for an all-solid-state battery according to claim 6.

8. the lithium ion conductor comprises an additional oxide comprising Na (sodium), Mg (magnesium), Al (aluminum), P (phosphorus), K (potassium), Ca (calcium), Ti (titanium), V (vanadium), Cr (chromium), Mn (manganese), Fe (iron), Co (cobalt), Ni (nickel), Cu (copper), Zn (zinc), Ga (gallium), Ge (germanium), Se (selenium), Rb (rubidium), S (sulfur), Y (yttrium), Zr (zirconium), Nb (niobium), Mo (molybdenum), Ag (silver), In (indium), Sn (tin), Sb (antimony), Cs (cesium), Ba (barium), Hf (hafnium), Ta (tantalum), W (tungsten), Pb (lead), Bi (bismuth), Au (gold), La (lanthanum), Nd (neodymium), Eu (europium), or a combination thereof; The lithium ion conductor for an all-solid-state battery according to claim 1 .

9. The lithium ion conductor further comprises an additional oxide comprising P (phosphorus) and Ge (germanium); The lithium ion conductor for an all-solid-state battery according to claim 1 .

10. The lithium ion conductor contains the additional oxide in an amount of 5 mol % or less based on the total amount of lithium (Li) oxide, silicon (Si) oxide, boron (B) oxide and the additional oxide contained in the lithium ion conductor. The lithium ion conductor for an all-solid-state battery according to claim 8.

11. The lithium ion conductor contains the additional oxide in an amount of 1 mol % or less based on the total amount of lithium (Li) oxide, silicon (Si) oxide, boron (B) oxide and the additional oxide contained in the lithium ion conductor. The lithium ion conductor for an all-solid-state battery according to claim 10.

12. A method for producing a lithium ion conductor, comprising sintering an oxide powder containing lithium (Li), silicon (Si) and boron (B) under pressure, The lithium ion conductor has a crystallinity of 25.5% or less.

13. The crystallinity is calculated according to Equation 1: The method according to claim 12, [Formula 1] Crystallinity (%) = [Ic / (Ic+Ia)] x 100, In the formula 1, Ic is the sum of integral values ​​of scattering intensity of crystal peaks in the X-ray diffraction analysis spectrum of the lithium ion conductor, Ia is the sum of integral values ​​of scattering intensity of amorphous halos in the X-ray diffraction analysis spectrum of the lithium ion conductor.

14. The calcination is carried out at a temperature of 300°C to 550°C; The method of claim 12.

15. During the pressurization, a pressure of 1 MPa to 200 MPa is applied. The method of claim 12.

16. An all-solid-state battery comprising a solid electrolyte layer, and a positive electrode and a negative electrode disposed with the solid electrolyte layer therebetween, one selected from the solid electrolyte layer, the positive electrode, the negative electrode, and a combination thereof includes a lithium ion conductor including an oxide including lithium (Li), silicon (Si), and boron (B); The lithium ion conductor has a crystallinity of 25.5% or less.

17. The crystallinity is calculated according to Equation 1: The all-solid-state battery according to claim 16: [Formula 1] Crystallinity (%) = [Ic / (Ic+Ia)] x 100, In the formula 1, Ic is the sum of integral values ​​of scattering intensity of crystal peaks in the X-ray diffraction analysis spectrum of the lithium ion conductor, Ia is the sum of integral values ​​of scattering intensity of amorphous halos in the X-ray diffraction analysis spectrum of the lithium ion conductor.

18. The lithium ion conductor has a porosity of 1% or less. The all-solid-state battery according to claim 16.

19. The lithium ion conductor contains 45 mol % to 80 mol % of lithium (Li) oxide, 5 mol % to 20 mol % of silicon (Si) oxide, and 15 mol % to 50 mol % of boron (B) oxide based on the total amount of lithium (Li) oxide, silicon (Si) oxide, and boron (B) oxide contained in the lithium ion conductor. The all-solid-state battery according to claim 16.

20. the lithium ion conductor further comprises an additional oxide comprising Na (sodium), Mg (magnesium), Al (aluminum), P (phosphorus), K (potassium), Ca (calcium), Ti (titanium), V (vanadium), Cr (chromium), Mn (manganese), Fe (iron), Co (cobalt), Ni (nickel), Cu (copper), Zn (zinc), Ga (gallium), Ge (germanium), Se (selenium), Rb (rubidium), S (sulfur), Y (yttrium), Zr (zirconium), Nb (niobium), Mo (molybdenum), Ag (silver), In (indium), Sn (tin), Sb (antimony), Cs (cesium), Ba (barium), Hf (hafnium), Ta (tantalum), W (tungsten), Pb (lead), Bi (bismuth), Au (gold), La (lanthanum), Nd (neodymium), Eu (europium), or a combination thereof; The all-solid-state battery according to claim 16.

21. the all-solid-state battery comprises: a laminate including a plurality of solid electrolyte layers, and a plurality of positive electrodes and negative electrodes arranged alternately with the plurality of solid electrolyte layers sandwiched therebetween; and first and second external electrodes connected to the positive electrodes and the negative electrodes, respectively, on one side surface and another side surface opposite to the one side surface of the laminate. The all-solid-state battery according to claim 16.

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