Oxide solid electrolyte, preparation method thereof, battery and electronic product

Abstract

The invention discloses an oxide solid electrolyte and a preparation method thereof, a battery and an electronic product, and the preparation method of the oxide solid electrolyte comprises the following steps: weighing precursor materials of a plurality of cationic elements according to a preset atomic percentage, and uniformly mixing to obtain a mixture; pre-sintering the mixture to obtain an oxide solid electrolyte precursor; carrying out pre-pressing molding on the oxide solid electrolyte precursor to obtain a pre-pressed block; carrying out high-temperature and high-pressure sintering on the pre-pressed block to obtain the oxide solid electrolyte; wherein the high-temperature and high-pressure sintering conditions are as follows: under the pressure condition of 1GPa-5.5 GPa and the temperature condition of 200 DEG C-850 DEG C, the temperature and the pressure are kept for 1-100 minutes. According to the method, the preparation temperature of the oxide solid electrolyte is reduced to 850 DEG C or below, meanwhile, the preparation time of the oxide solid electrolyte is shortened, a sintering aid does not need to be added, and accurate control over the oxide solid electrolyte combination is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of oxide solid electrolyte technology, and more particularly to an oxide solid electrolyte, its preparation method, battery, and electronic products. Background Technology

[0002] Graphene is an allotrope of carbon, in which carbon atoms are bonded in sp² hybridization to form a hexagonal honeycomb lattice. It has excellent optical, electrical and mechanical properties and has important application prospects in materials science, micro-nano fabrication, energy, biomedicine and drug delivery. It is considered a revolutionary material.

[0003] Currently, the main technologies for preparing oxide solid electrolytes include chemical vapor deposition (CVD), mechanical exfoliation, Joule heating, graphite oxide reduction, and epitaxial growth. However, CVD is costly and inefficient, while mechanical exfoliation is cost-effective and produces high-quality oxide solid electrolytes, but with extremely low yields. Joule heating can produce more than 1 gram of oxide solid electrolyte in a single step, but the quality of the product is uneven. Graphite oxide reduction has high production efficiency, but it requires both oxidants and reducing agents, making it environmentally unfriendly. Epitaxial growth can produce high-quality, large-area oxide solid electrolytes and is compatible with semiconductor processes.

[0004] In summary, the technology for efficiently preparing high-quality oxide solid electrolytes still needs further development. Summary of the Invention

[0005] This application provides an oxide solid electrolyte and its preparation method, as well as a battery and electronic product, to solve the technical problem that it is difficult to prepare high-quality oxide solid electrolyte bulk materials on a large scale and without pollution in the prior art.

[0006] In view of the above problems, this application is made in order to provide an oxide solid electrolyte that overcomes or at least partially solves the above problems, a method for preparing the same, a battery, and an electronic product.

[0007] This application provides a method for preparing an oxide solid electrolyte, comprising: According to the preset atomic percentage, the precursor materials of multiple cationic elements are weighed and mixed evenly to obtain a mixture. For each cationic element, the precursor material of that cationic element is selected from at least one of the oxides, carbonates, nitrates and hydroxides corresponding to that cationic element. The mixture is pre-sintered to obtain oxide solid electrolyte precursor; The oxide solid electrolyte precursor material is pre-pressed to obtain a pre-pressed block; The pre-compressed block is subjected to high-temperature and high-pressure sintering to obtain oxide solid electrolyte; wherein the high-temperature and high-pressure sintering conditions are: pressure conditions of 1GPa~5.5GPa and temperature conditions of 200℃~850℃, and holding at temperature and pressure for 1~100min.

[0008] Furthermore, the high-temperature and high-pressure sintering process includes: The pressure is increased to 1 GPa to 5.5 GPa at a rate of 0.12 to 2.35 GPa / min; Heating to 200℃~850℃ at a rate of 100℃ / min or higher; Under pressure conditions of 1 GPa to 5.5 GPa and temperature conditions of 200℃ to 850℃, maintain the temperature and pressure for 1 to 100 minutes; Cool to room temperature at a rate of 100~300℃ / min; Depressurize to atmospheric pressure at a rate of less than 1 GPa / min.

[0009] Furthermore, the pre-sintering conditions are: holding at 600℃~900℃ for 1min~100min.

[0010] Furthermore, the cationic element includes at least one of lithium, lanthanum, zirconium, aluminum, tantalum, sodium, germanium, boron, and silicon; precursor materials of multiple cationic elements are weighed according to a predetermined atomic percentage, including: Weigh out precursor materials containing multiple cationic elements according to the following atomic percentages: 0%~29% lithium, 0%~17% lanthanum, 0%~9% zirconium, 0%~25% aluminum, 0%~18% tantalum, 0%~15% sodium, 0%~12% germanium, 0%~14% boron, and 0%~10% silicon.

[0011] Furthermore, after obtaining the pre-compressed block, the process also includes: placing the pre-compressed block in a packaging assembly to obtain an assembled block; and subjecting the pre-compressed block to high-temperature and high-pressure sintering, including: placing the assembled block in a six-sided top press for high-temperature and high-pressure sintering. The encapsulation assembly includes, from the inside out, a salt tube, a carbon tube, a dolomite tube, and a pyrophyllite block. A pre-compression block is placed inside the salt tube. At the upper and lower ends of the pre-compression block, from the inside out, are arranged a salt sheet, a carbon sheet, a dolomite ring, a molybdenum sheet, and a steel plug, respectively. The salt sheet contacts the pre-compression block and seals the opening of the salt tube, and the carbon sheet contacts the salt sheet and seals the opening of the carbon tube. A carbon column is provided in the inner ring of the dolomite ring. One end of the carbon column contacts the carbon sheet, and the other end contacts the molybdenum sheet. At the upper and lower ends of the pyrophyllite block, there are openings coaxial with the dolomite tube. The steel plug is placed inside the opening and contacts the molybdenum sheet.

[0012] Furthermore, the oxide solid electrolyte precursor material is pre-pressed to obtain a pre-pressed block, comprising: The oxide solid electrolyte precursor is placed in a packaging material and pre-pressed in a mold to obtain a pre-pressed block.

[0013] Furthermore, the pre-compression block is a cylindrical block with a diameter ranging from 8 to 12 mm and a height ranging from 3 to 10 mm.

[0014] Secondly, this application provides an oxide solid electrolyte, which is prepared using the method described in the first aspect.

[0015] Thirdly, this application also provides a battery, including an anode layer, an electrolyte layer and a cathode layer disposed sequentially, wherein the material of the electrolyte layer includes an oxide solid electrolyte prepared by the method of the first aspect or an oxide solid electrolyte provided by the second aspect.

[0016] Fourthly, this application also provides an electronic product including the battery provided in the third aspect.

[0017] The technical solution provided in this application has at least the following technical effects or advantages: This application provides an oxide solid electrolyte, its preparation method, battery, and electronic product. It applies a temperature-pressure combined sintering technology to the preparation of the oxide solid electrolyte. By applying a pressure of 1 GPa to 5.5 GPa, the contact between the precursor particles and the internal porosity are altered, thereby reducing the preparation temperature of the oxide solid electrolyte to below 850°C. This also shortens the preparation time and eliminates the need for sintering aids, ensuring precise control of the oxide solid electrolyte composition. The oxide solid electrolyte provided in this application exhibits a bulk structure after preparation, with an ionic conductivity of 1.02 × 10⁻⁶. -4 It has a strength of s / cm or higher, and also possesses good mechanical strength (compression and flexural strength) and toughness.

[0018] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a flowchart illustrating the preparation method of the oxide solid electrolyte in the embodiments of this application; Figure 2 This is a schematic diagram of the assembly block structure in an embodiment of this application; Figure 3 The results of scanning electron microscopy characterization of the LATP ceramic block obtained in Example 1 of this application are shown. Figure 4 The XRD characterization results of the LATP ceramic block obtained in Example 1 of this application are shown below. Figure 5 The results of scanning electron microscopy characterization of the LLZO ceramic block obtained in Example 3 of this application are shown. Figure 6 The results of scanning electron microscopy characterization of the LLTO ceramic block obtained in Example 5 of this application are shown. Figure 7 The results of scanning electron microscopy characterization of the LAGP ceramic block obtained in Example 1 of this application are shown. Figure 8 This is a schematic diagram of the battery structure provided in an embodiment of this application. Detailed Implementation

[0020] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings.

[0021] The accompanying drawings illustrate various structural schematics according to embodiments of this application. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0022] To better understand the above technical solutions, the following will describe the above technical solutions in detail with reference to specific implementation methods. It should be understood that the embodiments of this disclosure and the specific features in the embodiments are detailed descriptions of the technical solutions of this application, rather than limitations on the technical solutions of this application. In the absence of conflict, the embodiments of this application and the technical features in the embodiments can be combined with each other.

[0023] In existing technologies, the synthesis method of oxide solid electrolytes is crucial to their final electrochemical performance, microstructure, and cost. Mainstream methods include solid-phase methods, solution chemistry methods, co-precipitation methods, and vapor deposition methods.

[0024] High-temperature solid-state reaction methods are simple and low-cost, making them suitable for large-scale production. However, they are energy-intensive, have long sintering times, and are prone to lithium volatilization and impurity phase formation, resulting in coarse oxide solid electrolyte powder particles with high grain boundary impedance, often requiring secondary sintering or the addition of sintering aids to improve their properties. Solution chemistry methods offer good component uniformity and high powder activity, but are relatively expensive and have long production cycles. Co-precipitation methods are easy to scale up and can effectively control particle morphology, but may suffer from component segregation. Pulsed laser deposition (PLD), magnetron sputtering, and other vapor deposition methods can directly prepare dense, high-performance electrolyte films on substrates, but the equipment is expensive and yields are extremely low.

[0025] In view of this, embodiments of this application provide a method for preparing an oxide solid electrolyte, such as... Figure 1 As shown, the method includes the operations described in S101 to S104 below.

[0026] S101. Weigh out the precursor materials of multiple cationic elements according to the preset atomic percentage, mix them evenly to obtain a mixture, wherein, for each of the multiple cationic elements, the precursor material of the cationic element is selected from at least one of the oxides, carbonates, nitrates and hydroxides corresponding to the cationic element.

[0027] S102. The mixture is pre-sintered to obtain oxide solid electrolyte precursor.

[0028] S103. The oxide solid electrolyte precursor material is pre-pressed to obtain a pre-pressed block.

[0029] S104. The pre-compressed block is subjected to high-temperature and high-pressure sintering to obtain an oxide solid electrolyte. The high-temperature and high-pressure sintering conditions are: pressure of 1 GPa to 5.5 GPa and temperature of 200℃ to 850℃, and holding at the temperature and pressure for 1 to 100 minutes.

[0030] In some optional embodiments, the cationic element includes at least one selected from lithium, lanthanum, zirconium, aluminum, tantalum, sodium, germanium, boron, and silicon; the specific operation of S101 above includes: weighing precursor materials of multiple cationic elements according to the following atomic percentages: 0%~29% lithium, 0%~17% lanthanum, 0%~9% zirconium, 0%~25% aluminum, 0%~18% tantalum, 0%~15% sodium, 0%~12% germanium, 0%~14% boron, and 0%~10% silicon.

[0031] The mainstream components of oxide solid electrolytes include: lithium aluminum titanium phosphate (LATP), garnet-type lithium lanthanum zirconium oxide (LLZO), lithium lanthanum titanate (LLTO), and lithium aluminum gallium phosphate (LAGP), etc.; among them, LATP has the molecular formula Li. 1+x Alx Ti 2-x (PO4)3, where x is usually 0.3 - 0.5, for example, it can be 0.3, 0.4 or 0.5; the molecular formula of LLZO is Li7La3Zr2O 12 ; the molecular formula of LLTO is Li 0.33 La 0.56 TiO3; the molecular formula of LAGP is Li 1+x Al x Ge 2-x (PO4)3, where 0 < x < 2, for example, it can be 0.1, 0.2, 0.3, 0.5, 0.7, 0.9, 1, 1.2 or 1.5. The oxide solid electrolyte can also be Na3Zr2Si2PO 12 、Li 14 ZnGe4O 16 、LiAlO2、La 0.85 Li 0.15 TiO3、LiBO2 and other components.

[0032] The precursor material of the cationic element provided in the above S101 operation can be a powder material with a particle size of 10 nm - 10 μm. The present application does not limit the specific particle size of the precursor material of the cationic element.

[0033] The purpose of the pre-sintering in the above S102 step is to lay a foundation for the subsequent preparation of high-performance oxide solid electrolytes. The mixture usually uses oxides, carbonates, nitrates and hydroxides corresponding to the target cationic elements. Therefore, the mixture contains non-target components such as carbon, nitrogen and hydrogen. These non-target components are removed by pre-sintering heating. On the one hand, it avoids the residue of non-target components, which affects the electrical and mechanical properties of the oxide solid electrolyte. On the other hand, it prevents the appearance of pores and cracks in the bulk of the oxide solid electrolyte during the subsequent sintering process. On the third hand, it avoids the appearance of impurity phases during the subsequent sintering process.

[0034] In some optional embodiments, the conditions of the pre-sintering are: heat preservation for 1 min - 100 min under the temperature condition of 600 °C - 900 °C. The temperature condition can specifically be selected as 600 °C, 620 °C, 650 °C, 670 °C, 700 °C, 750 °C, / 780 °C, 800 °C, 810 °C, 830 °C, 850 °C, 870 °C, 880 °C or 900 °C. The time of the pre-sintering can specifically be selected as 1 min, 5 min, 10 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min or 100 min.

[0035] If the pre-sintering temperature is too high, such as exceeding 900℃, or the time is too long, such as exceeding 100 minutes, the morphology of the oxide solid electrolyte precursor will be irregular due to excessive growth of the target phase. During subsequent pre-pressing, the oxide solid electrolyte precursor is difficult to pack tightly due to the large interparticle friction and poor flowability, resulting in low density and uneven density distribution of the pre-pressed block. Finally, the oxide solid electrolyte block material obtained after sintering will have defects such as porosity, cracking, compositional deviation and low density.

[0036] If the pre-sintering temperature is too low or the time is too short, the non-target components will remain in large quantities, resulting in more defects in the oxide solid electrolyte bulk material obtained by subsequent sintering. The non-target components that are not completely removed will also cause side reactions and exacerbate the composition deviation.

[0037] In step S103 above, pre-compression molding is used to initially compact the oxide solid electrolyte precursor material, reducing the gaps between the precursor particles, increasing density, and improving the yield of subsequent oxide solid electrolyte bulk materials. Furthermore, the pre-compressed blocks obtained through pre-compression molding have relatively stable shapes and dimensions, which is beneficial for uniform stress distribution during subsequent sintering and prevents sintering failure of the oxide solid electrolyte due to pressure unevenness causing seal failure and pressure release.

[0038] In some examples, in step S103 above, the oxide solid electrolyte precursor is placed in a packaging material and pre-pressed in a mold to obtain a pre-pressed block.

[0039] The encapsulation material is used to constrain the shape of the oxide solid electrolyte precursor during pre-compression molding, while protecting the precursor and preventing material contamination. The encapsulation material can be made of elemental metals such as gold, platinum, silver, tungsten, molybdenum, iridium, or ruthenium, or alloys such as platinum-rhodium alloys or nickel-based alloys. This application does not specify the exact material of the encapsulation material.

[0040] For example, the packaging material can be a molybdenum cup. The oxide solid electrolyte precursor is filled into two circular molybdenum cups, the two molybdenum cups are snapped together, and then placed in a mold for pre-pressing to obtain a cylindrical pre-pressed block.

[0041] In some alternative implementations, the preload block is a cylindrical block with a diameter ranging from 8 to 12 mm and a height ranging from 3 to 10 mm.

[0042] For example, the oxide solid electrolyte precursor is placed in a molybdenum cup and pre-compressed into a cylindrical pre-compressed block with a diameter of 10 mm and a height of about 8 mm under a pressure of 10 MPa.

[0043] In step S104 above, the heat and pressure provided by the high-temperature and high-pressure sintering process enable the large-scale, pollution-free preparation of high-quality bulk materials of oxide solid electrolytes.

[0044] In some optional embodiments, after obtaining the pre-compressed block by performing the operation in S103 above, the method further includes: placing the pre-compressed block in a packaging assembly to obtain an assembled block. In step S104, the assembled block is subjected to high-temperature and high-pressure sintering to obtain a bulk material of the oxide solid electrolyte.

[0045] High-temperature and high-pressure sintering requires high-temperature and high-pressure equipment. Existing high-temperature and high-pressure equipment includes two-sided and multi-sided presses. Two-sided presses include piston-cylinder presses, annual ring presses, Bridgman presses, and concave anvil presses. Multi-sided presses include four-sided, six-sided, and eight-sided presses, etc. This application does not limit the high-temperature and high-pressure equipment used in high-temperature and high-pressure sintering.

[0046] The following example illustrates how to perform the above S104 operation using high-temperature and high-pressure equipment.

[0047] Taking a six-sided top press as an example, the operation of S104 above specifically includes placing the assembly block in the six-sided top press for high-temperature and high-pressure sintering.

[0048] When the six-sided top press is used in the operation described in S104 above, such as Figure 2 As shown, the encapsulation assembly includes, from the inside out, a salt tube 201, a carbon tube 202, a dolomite tube 203, and a pyrophyllite block 204. A pre-compression block 205 is disposed within the salt tube 201. At the upper and lower ends of the pre-compression block 205, from the inside out, are respectively arranged a salt sheet 206, a carbon sheet 207, a dolomite ring 208, a molybdenum sheet 209, and a steel plug 210. The salt sheet 206 is in contact with the pre-compression block 205. The opening of the salt tube 201 is sealed, the carbon sheet 207 contacts the salt sheet 206 and seals the opening of the carbon tube 202, the inner ring of the dolomite ring 208 is provided with a carbon column 211, one end of the carbon column 211 contacts the carbon sheet 207 and the other end contacts the molybdenum sheet 209, the upper and lower ends of the pyrophyllite block 204 are respectively provided with openings coaxial with the dolomite tube 203, and the steel plug 210 is set in the opening and contacts the molybdenum sheet 209.

[0049] The six-sided top press mainly consists of six top hammers, typically arranged in a cubic layout, corresponding to the six directions of up / down, front / back, and left / right. Each top hammer is connected to an independent hydraulic system. In the operation of S104 described above, when the six-sided top press is working, the hydraulic system controls the top hammers to move towards the center, compressing the assembly block placed in the middle of the six top hammers from all directions. This creates a uniform high-pressure environment in the space where the pre-compressed block is located. By controlling the stroke of the top hammers through the hydraulic system, a pressure of 1 GPa to 5.5 GPa can be generated to act on the oxide solid electrolyte precursor material in the pre-compressed block.

[0050] The six-sided top press is equipped with a heating device and a temperature control system. The heating device generally uses resistance heating or high-frequency induction heating. Resistance heating involves connecting the steel plugs at both ends of the assembly to a power source. When current passes through the heating element, which is mainly composed of carbon tubes, heat is generated due to the resistance, thus raising the temperature around the pre-pressed block inside the salt tube to 200℃~850℃. This heat acts on the oxide solid electrolyte precursor material in the pre-pressed block.

[0051] The hydraulic system works in conjunction with the heating device to generate sintering conditions of 1GPa~5.5GPa and 200℃~850℃ on the oxide solid electrolyte precursor material in the pre-compressed block, forming a dense oxide solid electrolyte bulk material.

[0052] Based on the hydraulic system and heating device, the high-temperature and high-pressure sintering process in the above-mentioned S104 operation includes: S1, Pressure conditions where the pressure is increased to 1 GPa to 5.5 GPa at a rate of 0.12 to 2.35 GPa / min; S2, Temperature conditions where the temperature is increased to 200℃-850℃ at a rate of 100℃ / min or higher; S3. Under pressure conditions of 1GPa~5.5GPa and temperature conditions of 200℃~850℃, maintain the temperature and pressure for 1~100min; S4. Cool the temperature down to room temperature at a cooling rate of 100~300℃ / min; S5. Reduce the pressure to atmospheric pressure at a rate of less than 1 GPa / min.

[0053] It is understood that the pressurization operation in S1 and the heating operation in S2 can be performed simultaneously or sequentially, and the cooling operation in S4 and the depressurization operation in S5 can be performed simultaneously or sequentially. This application embodiment does not limit the time order of pressurization and heating, nor does it limit the time order of cooling and depressurization.

[0054] The following examples illustrate how to prepare high-quality oxide solid electrolyte bulk materials on a large scale and without pollution using the methods provided in the embodiments of this application.

[0055] Example 1 This embodiment provides a bulk material for an oxide solid electrolyte, the composition of which is Li. 1.4 Al 0.4 Ti 1.6 (PO4)3, its preparation method includes the following steps: The first step is to determine the molecular formula Li. 1.4 Al 0.4 Ti 1.6 The atomic percentage indicated by (PO4)3 is used to weigh the precursor materials of Li, Al, Ti and P, mix them evenly to obtain a mixture, wherein the precursor material of Li is Li2CO3, the precursor material of Al is Al2O3, the precursor material of Ti is TiO2, and the precursor material of P is NH4H2PO4. The second step is to pre-sinter the mixture at 700℃ for 30 minutes to obtain oxide solid electrolyte precursor. The third step is to pre-press the oxide solid electrolyte precursor material to obtain a cylindrical pre-press block with a diameter of 10 mm and a height of 8 mm. The fourth step is to place the pre-compressed block into the packaging assembly to obtain... Figure 2 The assembly blocks of the structure shown; The fifth step involves placing the assembly block in a high-temperature and high-pressure equipment such as a six-sided top press, pressurizing it to 5.5 GPa at a rate of 0.12 GPa / min, heating it to 850°C at a rate of 160°C / min, and maintaining the pressure and temperature at 5.5 GPa and 850°C for 10 minutes; then cooling it down at a rate of 200°C / min, followed by depressurization at a rate of 0.5 GPa / min. The sixth step is to remove the sintered assembly block, remove the encapsulating components, and obtain the block sintered body of oxide solid electrolyte, namely LATP ceramic block. The yield of a single LATP run is related to the sample chamber size of the high-pressure equipment used.

[0056] See appendix Figure 3 SEM characterization of the LATP ceramic block showed that the prepared material was very dense.

[0057] See attached document Figure 4 XRD characterization of the LATP ceramic block showed that the composition of the synthesized material met expectations.

[0058] Further EIS characterization of the LATP ceramic block revealed an ionic conductivity of 1.02 × 10⁻⁶. -4 The s / cm indicates that it has excellent electrical conductivity. Mechanical property tests showed that its hardness was 11.2 GPa and its elastic modulus reached 100.47 GPa, indicating that it has excellent resistance to deformation and structural stability.

[0059] Example 2 The difference between this embodiment and Embodiment 1 is that in step five, the assembly block is placed in a high-temperature and high-pressure device such as a six-sided top press, pressurized to 1 GPa at a rate of 0.12 GPa / min, heated to 200°C at a rate of 160°C / min, and held at 1 GPa pressure and 200°C temperature for 10 minutes. Then, it is cooled at a rate of 200°C / min, and subsequently depressurized at a rate of 0.5 GPa / min.

[0060] The LATP ceramic block prepared in this embodiment was characterized by EIS, and the results showed that its ionic conductivity was 5.6 × 10⁻⁶. -4 The s / cm indicates that it has excellent electrical conductivity. Mechanical property tests show that its hardness is 4.5GPa and its elastic modulus reaches 158GPa, indicating that it has excellent resistance to deformation and structural stability.

[0061] Example 3 This embodiment provides a bulk material for an oxide solid electrolyte, the composition of which is Li7La3Zr2O. 12 Its preparation method includes the following steps: The first step is to determine the molecular formula Li7La3Zr2O. 12 The indicated atomic percentages are used to weigh the precursor materials of Li, La, and Zr, mix them evenly, and obtain a mixture. Among them, the precursor material of Li is LiOH, the precursor material of La is La2O3, and the precursor material of Zr is ZrO2. The second step is to pre-sinter the mixture at 700℃ for 30 minutes to obtain oxide solid electrolyte precursor. The third step is to pre-press the oxide solid electrolyte precursor material to obtain a cylindrical pre-press block with a diameter of 10 mm and a height of 8 mm. The fourth step is to place the pre-compressed block into the packaging assembly to obtain... Figure 2 The assembly blocks of the structure shown; The fifth step involves placing the assembly block in a high-temperature and high-pressure equipment such as a six-sided top press, pressurizing it to 5.5 GPa at a rate of 0.12 GPa / min, heating it to 850°C at a rate of 160°C / min, and maintaining the pressure and temperature at 5.5 GPa and 850°C for 10 minutes; then cooling it down at a rate of 200°C / min, followed by depressurization at a rate of 0.5 GPa / min. Step 6: Remove the sintered assembly block, remove the encapsulating components, and obtain a block sintered body of oxide solid electrolyte. Grind the block sintered body of oxide solid electrolyte to obtain an LLZO ceramic block with a diameter of 7.5 mm and a height of 5.9 mm.

[0062] See appendix Figure 5 SEM characterization of the LLZO ceramic block showed that the prepared material was very dense. EIS characterization of the LLZO ceramic block showed that its ionic conductivity was 3 × 10⁻⁶. -4 The s / cm indicates that it has excellent electrical conductivity. Mechanical property tests show that its hardness is 2GPa and its elastic modulus reaches 174GPa, indicating that it has excellent resistance to deformation and structural stability.

[0063] Example 4 The difference between this embodiment and Embodiment 3 is that in the fifth step, the assembly block is placed in a high-temperature and high-pressure device such as a six-sided top press, pressurized to 1 GPa at a rate of 0.12 GPa / min, heated to 200°C at a rate of 160°C / min, and held at 1 GPa pressure and 200°C temperature for 10 minutes. Then, it is cooled at a rate of 200°C / min, and subsequently depressurized at a rate of 0.5 GPa / min.

[0064] The LLZO ceramic block prepared in this embodiment was characterized by EIS, and the results showed that its ionic conductivity was 1.6 × 10⁻⁶. -4 The s / cm indicates that it has excellent electrical conductivity. Mechanical property tests showed that its hardness was 2.3 GPa and its elastic modulus reached 167 GPa, indicating that it has excellent resistance to deformation and structural stability.

[0065] Example 5 This embodiment provides a bulk material for an oxide solid electrolyte, the composition of which is Li. 0.33 La 0.56 TiO3 is prepared by the following steps: The first step is to determine the molecular formula Li. 0.33 La 0.56 The atomic percentage indicated by TiO3 is determined by weighing the precursor materials of Li, La, and Ti, mixing them evenly to obtain a mixture. The precursor material of Li is lithium nitrate (LiNO3), the precursor material of La is lanthanum nitrate (La(NO3)3), and the precursor material of Ti is TiO2. The second step is to pre-sinter the mixture at 500℃ for 40 minutes to obtain oxide solid electrolyte precursor. The third step is to pre-press the oxide solid electrolyte precursor material to obtain a cylindrical pre-press block with a diameter of 10 mm and a height of 10 mm. The fourth step is to place the pre-compressed block into the packaging assembly to obtain... Figure 2 The assembly blocks of the structure shown; The fifth step involves placing the assembly block in a high-temperature and high-pressure equipment such as a six-sided top press, pressurizing it to 5.5 GPa at a rate of 0.12 GPa / min, heating it to 850°C at a rate of 160°C / min, and maintaining the pressure and temperature at 5.5 GPa and 850°C for 10 minutes; then cooling it down at a rate of 200°C / min, followed by depressurization at a rate of 0.5 GPa / min. Step 6: Remove the sintered assembly block, remove the encapsulating components, and obtain a block sintered body of oxide solid electrolyte. Grind the block sintered body of oxide solid electrolyte to obtain an LLTO ceramic block with a diameter of 9.7 mm and a height of 4.1 mm.

[0066] See appendix Figure 6 SEM characterization of the LLTO ceramic block showed that the prepared material was very dense. EIS characterization of the LLTO ceramic block showed that its ionic conductivity was 9.6 × 10⁻⁶. -4 The s / cm indicates that it has excellent electrical conductivity. Mechanical property tests show that its hardness is 2GPa and its elastic modulus reaches 165GPa, indicating that it has excellent resistance to deformation and structural stability.

[0067] Example 6 The difference between this embodiment and Embodiment 5 is that in the fifth step, the assembly block is placed in a high-temperature and high-pressure device such as a six-sided top press, pressurized to 3GPa at a rate of 0.15GPa / min, heated to 400℃ at a rate of 120℃ / min, and held at 3GPa pressure and 400℃ temperature for 10 minutes. Then, it is cooled at a rate of 100℃ / min, and subsequently depressurized at a rate of 0.8GPa / min.

[0068] The LLTO ceramic block prepared in this embodiment was characterized by EIS, and the results showed that its ionic conductivity was 9.1 × 10⁻⁶. -4 The s / cm indicates that it has excellent electrical conductivity. Mechanical property tests showed that its hardness was 2.1 GPa and its elastic modulus reached 158 GPa, indicating that it has excellent resistance to deformation and structural stability.

[0069] Example 7 This embodiment provides a bulk material for an oxide solid electrolyte, the composition of which is Li. 1.5 Al 0.5 Ge 1.5 (PO4)3, its preparation method includes the following steps: The first step is to determine the molecular formula Li. 1.5 Al 0.5 Ge 1.5The atomic percentage indicated by (PO4)3 is used to weigh the precursor materials of Li, Al, Ge and P, mix them evenly to obtain a mixture, wherein the precursor material of Li is lithium nitrate (LiNO3), the precursor material of Al is Al2O3, the precursor material of Ge is GeO2 and the precursor material of P is H3PO4. The second step is to pre-sinter the mixture at 900℃ for 10 minutes to obtain oxide solid electrolyte precursor. The third step is to pre-press the oxide solid electrolyte precursor material to obtain a cylindrical pre-press block with a diameter of 10 mm and a height of 10 mm. The fourth step is to place the pre-compressed block into the packaging assembly to obtain... Figure 2 The assembly blocks of the structure shown; The fifth step involves placing the assembly block in a high-temperature and high-pressure equipment such as a six-sided top press, pressurizing it to 5.5 GPa at a rate of 0.12 GPa / min, heating it to 850°C at a rate of 160°C / min, and maintaining the pressure and temperature at 5.5 GPa and 850°C for 10 minutes; then cooling it down at a rate of 200°C / min, followed by depressurization at a rate of 0.5 GPa / min. Step 6: Remove the sintered assembly block, remove the encapsulating components, and obtain a block sintered body of oxide solid electrolyte. Grind the block sintered body of oxide solid electrolyte to obtain a LAGP ceramic block with a diameter of 10 mm and a height of 9.6 mm.

[0070] See appendix Figure 7 SEM characterization of the LAGP ceramic block showed that the prepared material was very dense. EIS characterization of the LAGP ceramic block showed that its ionic conductivity was 1.23 × 10⁻⁶. -4 The s / cm indicates that it has excellent electrical conductivity. Mechanical property tests show that its hardness is 3.4 GPa and its elastic modulus reaches 150 GPa, indicating that it has excellent resistance to deformation and structural stability.

[0071] Example 8 The difference between this embodiment and Embodiment 7 is that in step five, the assembly block is placed in a high-temperature and high-pressure device such as a six-sided top press, pressurized to 4 GPa at a rate of 1 GPa / min, heated to 400°C at a rate of 120°C / min, and held at 4 GPa pressure and 400°C temperature for 30 minutes. Then, it is cooled at a rate of 180°C / min, and subsequently depressurized at a rate of 0.5 GPa / min.

[0072] The LAGP ceramic block prepared in this embodiment was characterized by EIS, and the results showed that its ionic conductivity was 1.1 × 10⁻⁶. -4The s / cm indicates that it has excellent electrical conductivity. Mechanical property tests showed that its hardness was 2.9 GPa and its elastic modulus reached 147 GPa, indicating that it has excellent resistance to deformation and structural stability.

[0073] In summary, the oxide solid electrolyte prepared by the method provided in this application has excellent electrical and mechanical properties.

[0074] Based on the same inventive concept, embodiments of this application also provide a battery, such as... Figure 8 As shown, the battery 800 includes an anode layer 801, an electrolyte layer 802, and a cathode layer 803 arranged sequentially. The electrolyte layer 802 is made of an oxide solid electrolyte prepared by any of the methods described in Examples 1 to 8.

[0075] For example, the battery 800 described above can be a button cell battery. The bulk material of the oxide solid electrolyte provided in embodiments 1 to 8 is cut to form oxide solid electrolyte sheets with a diameter of 8 mm and a thickness of 2 mm. These oxide solid electrolyte sheets are then loaded into the battery using the same process to obtain button cells with a diameter of 10 mm and a thickness of 5 mm. The gravimetric energy density of these button cells in air can reach more than 790 Wh / kg, proving that the battery provided in the embodiments of this application has good energy storage effect.

[0076] Based on the same inventive concept, this application also provides an electronic product that includes the battery provided in the above embodiments.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

[0078] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

Claims

1. A method for producing an oxide solid-state electrolyte, characterized by, The application relates to a method for preparing an oxide solid-state electrolyte. According to a preset atomic percentage, precursor materials of multiple cation elements are weighed and mixed to obtain a mixture, wherein, for each cation element of the multiple cation elements, the precursor material of the cation element is selected from at least one of oxides, carbonates, nitrates and hydroxides corresponding to the cation element; The mixture is pre-sintered to obtain an oxide solid-state electrolyte precursor; The oxide solid-state electrolyte precursor is pre-pressed to form a pre-pressed block; The pre-pressed block is sintered under high temperature and high pressure to obtain an oxide solid-state electrolyte, wherein the sintering under high temperature and high pressure is carried out under the conditions of a pressure of 1 GPa to 5.5 GPa and a temperature of 200 DEG C to 850 DEG C for 1 min to 100 min.

2. The method for producing an oxide solid electrolyte according to claim 1, characterized by, The sintering process under high temperature and high pressure comprises the following steps: The pressure is increased to 1 GPa to 5.5 GPa at a rate of 0.12 GPa / min to 2.35 GPa / min; The temperature is increased to 200 DEG C to 850 DEG C at a rate of 100 DEG C / min or more; The sintering under high temperature and high pressure is carried out under the conditions of a pressure of 1 GPa to 5.5 GPa and a temperature of 200 DEG C to 850 DEG C for 1 min to 100 min; The temperature is decreased to room temperature at a rate of 100 DEG C / min to 300 DEG C / min; The pressure is decreased to normal pressure at a rate of 1 GPa / min or less.

3. The method for producing an oxide solid electrolyte according to claim 1, characterized by, The pre-sintering is carried out under the conditions of a temperature of 600 DEG C to 900 DEG C for 1 min to 100 min.

4. The method for producing an oxide solid electrolyte according to claim 1, characterized by, The cation elements include at least one of lithium, lanthanum, zirconium, aluminum, tantalum, sodium, germanium, boron and silicon; and the weighing of the precursor materials of the multiple cation elements according to the preset atomic percentage comprises the following steps: The precursor materials of the multiple cation elements are weighed according to the following atomic percentage: 0% to 29% of lithium, 0% to 17% of lanthanum, 0% to 9% of zirconium, 0% to 25% of aluminum, 0% to 18% of tantalum, 0% to 15% of sodium, 0% to 12% of germanium, 0% to 14% of boron and 0% to 10% of silicon.

5. The method for producing an oxide solid electrolyte according to claim 1, characterized by, After the pre-pressed block is obtained, the pre-pressed block is placed in a wrapping assembly to obtain an assembled block; and the sintering of the pre-pressed block under high temperature and high pressure comprises the following steps: The wrapping assembly comprises a salt pipe, a carbon pipe, a dolomite pipe and a pyrophyllite block which are sequentially sleeved from inside to outside; the pre-pressed block is arranged in the salt pipe; the upper and lower ends of the pre-pressed block are sequentially provided with a salt sheet, a carbon sheet, a dolomite ring, a molybdenum sheet and a steel plug from inside to outside; the salt sheet is in contact with the pre-pressed block and blocks the opening of the salt pipe; the carbon sheet is in contact with the salt sheet and blocks the opening of the carbon pipe; the inner circle of the dolomite ring is provided with a carbon column, one end of the carbon column is in contact with the carbon sheet, and the other end is in contact with the molybdenum sheet; the upper and lower ends of the pyrophyllite block are respectively provided with through holes coaxial with the dolomite pipe; and the steel plug is arranged in the through hole and is in contact with the molybdenum sheet.

6. The method for producing an oxide solid electrolyte according to claim 1, characterized by, The pre-pressed block is obtained by pre-pressing the oxide solid-state electrolyte precursor. The oxide solid electrolyte precursor is placed in a wrapping material and pre-pressed into a mold to obtain the pre-pressed block.

7. The method of producing an oxide solid state electrolyte according to claim 1, wherein The pre-pressed block is a cylindrical block with a diameter in the range of 8-12 mm and a height in the range of 3-10 mm.

8. An oxide solid state electrolyte, characterized by, The oxide solid electrolyte is prepared by the method of any one of claims 1-7.

9. A battery, characterized by The battery comprises an anode layer, an electrolyte layer, and a cathode layer arranged in sequence, wherein the material of the electrolyte layer comprises the oxide solid electrolyte prepared by the method of any one of claims 1-7 or the oxide solid electrolyte of claim 8.

10. An electronic product, characterized by comprising: The battery comprises the battery of claim 9.

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