Conductive ceramic additive / solid electrolyte composite and method for preparing the same
By adding composite materials containing LaNbO4 with components such as NZSP, LATP, LLT, 8YSZ, or SrTiO3, the problems of low room temperature ionic conductivity and poor grain boundary contact in solid electrolyte materials have been solved, resulting in improved high conductivity and stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SOUTHWEST PETROLEUM UNIV
- Filing Date
- 2024-07-23
- Publication Date
- 2026-06-26
AI Technical Summary
Existing solid electrolyte materials suffer from low room temperature ionic conductivity and poor grain boundary contact, which can lead to cracking during long-term operation.
A method for preparing conductive ceramic additive/solid electrolyte composite materials is adopted. By adding LaNbO4 with components such as NZSP, LATP, LLT, 8YSZ or 3YSZ, and SrTiO3, a composite material is formed, which improves grain boundary characteristics, alleviates thermal expansion mismatch, and forms a favorable intermediate phase.
It significantly reduces grain boundary impedance, increases room temperature ionic conductivity, enhances the electrical conductivity of materials, reduces microcracks caused by thermal expansion, and improves the stability and conductivity of materials.
Smart Images
Figure CN118754634B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of solid electrolyte materials technology, specifically relating to conductive ceramic additive / solid electrolyte composite materials and their preparation methods. Background Technology
[0002] Energy is a crucial cornerstone of the rapid development of human society. Every technological advancement is underpinned by upgrades and iterations in energy utilization. Traditional fossil fuels such as oil, coal, and natural gas are not only finite in reserves but also non-renewable, making them unsustainable in today's rapidly evolving technological landscape. Furthermore, the harmful gases produced during fossil fuel use not only pollute the environment but also exacerbate the greenhouse effect. Since the beginning of the 21st century, the energy crisis and environmental protection have become two major challenges facing humanity. To address these challenges, governments worldwide are vigorously promoting renewable and clean energy. Against this backdrop, emerging energy sources such as wind, hydro, and solar power have emerged, and their related research and development have flourished in recent years. However, while these renewable and clean energy sources offer numerous advantages, their intermittent power supply is limited by practical operating environments. Therefore, developing corresponding energy storage equipment is crucial. Electrochemical energy storage technology offers advantages such as high energy efficiency, long lifespan, and wide applicability. However, traditional energy storage technologies mostly employ liquid organic electrolytes, which pose serious safety hazards, such as easy leakage and flammability / explosiveness, greatly limiting their application in large-scale energy storage systems. Compared to traditional organic liquid electrolyte materials, solid-state electrolyte materials are considered to offer higher safety and stability. Solid-state electrolytes possess greater thermal stability and non-flammability, giving them a significant advantage in safety. Furthermore, solid-state electrolytes help improve the overall energy density of the entire battery because they allow the use of higher-capacity electrode materials and can be more tightly integrated into the battery system.
[0003] In conclusion, the research and performance optimization of solid electrolyte materials are crucial to the development of electrochemical energy storage technology. Room temperature ionic conductivity is a key performance indicator that determines whether solid electrolyte materials can be applied as soon as possible. Through technological breakthroughs, improving the ionic conductivity of solid electrolytes at room temperature will promote the research and development of efficient and practical solid electrolyte materials, thereby accelerating the commercialization of all-solid-state battery technology. This is of great significance for promoting energy transition and achieving sustainable development. Summary of the Invention
[0004] The purpose of this invention is to address the problems of low room temperature ionic conductivity and poor grain boundary contact in existing solid electrolyte materials, which lead to cracking during long-term operation, by providing a conductive ceramic additive / solid electrolyte composite material and its preparation method.
[0005] The conductive ceramic additive / solid electrolyte composite material has the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, wherein 0.5mol%≤x≤3mol%, and only one of y, z, α, β and γ is not 0;
[0006] The NZSP is Na d Zr e Si f P g O 12 Where d, e, f, and g are all non-zero; the LATP mentioned is Li a Al b Ti c P3O 12 Where a, b, and d are all non-zero; the LLT mentioned is Li m La n TiO3, wherein m and n are both non-zero; the 8YSZ is 8 mol% Y2O3-stabilized ZrO2, and the 3YSZ is 3 mol% Y2O3-stabilized ZrO2.
[0007] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0008] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and z, α, β and γ are all 0, weigh NaNO3, ZrO(NO3)2, NH4NbO(C2O4)2, La(NO3)3, Si(OCH2CH3)4 and NH4H2PO4 according to the stoichiometric ratio;
[0009] 2. The NaNO3 and ZrO(NO3)2 weighed above were dissolved in deionized water by stirring. Then, NH4NbO(C2O4)2 and La(NO3)3 weighed were added in sequence and stirred until the solution was clear. Then, Si(OCH2CH3)4 and NH4H2PO4 weighed were added and stirred to obtain a gel-like solution. The solution was dried to obtain a dry gel.
[0010] 3. The above-mentioned dry gel is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 1000-1500℃ for 3-10 hours to obtain xLaNbO4-NZSP composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0011] Where NZSP is Na d Zr eSi f P g O 12 , where d, e, f, and g are all non-zero.
[0012] Furthermore, the drying process described in step two involves drying at 50–100°C.
[0013] Furthermore, in step three, after ball milling and drying, the product is compressed into tablets: anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-48h. Then, it is dried at 50-100℃ for 12-48h and compressed into tablets using a tablet press.
[0014] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0015] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, α, β and γ are all 0, weigh LiNO3, Al(NO3)3, NH4NbO(C2O4)2, La(NO3)3, Ti[OCH(CH3)2]4 and NH4H2PO4 according to the stoichiometric ratio;
[0016] 2. The weighed LiNO3 and Al(NO3)3 were dissolved in deionized water by stirring. Then, the weighed NH4NbO(C2O4)2 and La(NO3)3 were added and stirred until dissolved. HNO3 was then added to adjust the pH of the solution to 0.8-1.2. Finally, the weighed Ti[OCH(CH3)2]4 and NH4H2PO4 were added and stirred to obtain the final product solution. After drying, a rough solid powder was obtained.
[0017] 3. The above-mentioned rough solid powder is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 900-1500℃ for 3-10 hours to obtain xLaNbO4-LATP composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0018] Where LATP is Li a Al b Ti c P3O 12 , where a, b, and d are all non-zero.
[0019] Furthermore, the drying process described in step two involves drying at 50–100°C.
[0020] Furthermore, in step three, after ball milling and drying, the product is compressed into tablets: anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-48h. Then, it is dried at 50-100℃ for 12-48h and compressed into tablets using a tablet press.
[0021] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0022] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, β and γ are all 0, weigh LiNO3, La(NO3)3, Ti[OCH(CH3)2]4, La2O3 and Nb2O5 according to the stoichiometric ratio;
[0023] 2. The weighed LiNO3 and La(NO3)3 were stirred and dissolved in deionized water. HNO3 was added to make the pH of the solution 0.8-1.2. Then, the weighed Ti[OCH(CH3)2]4 was added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. After drying, a solid polymer resin was obtained.
[0024] 3. The above solid polymer resin is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles. Then, weighed La2O3 and Nb2O5 are added, and after ball milling and drying, the mixture is pressed into sheets. Then, it is placed in a muffle furnace and calcined at 900-1500℃ for 3-10 hours to obtain xLaNbO4-LLT composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0025] Where LLT is Li m La n TiO3, where neither m nor n is 0.
[0026] Furthermore, in step two, the ratio of the number of moles of citric acid to the total number of moles of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5-10% of the total volume of the final product solution.
[0027] Furthermore, the drying process described in step two involves drying at 200–500°C.
[0028] Furthermore, in step three, after ball milling and drying, the product is compressed into tablets: anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-72h. Then, it is dried at 50-100℃ for 12-48h and compressed into tablets using a tablet press.
[0029] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0030] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, α and γ are all 0, weigh ZrO(NO3)2, Y(NO3)3, NH4NbO(C2O4)2 and La(NO3)3 according to the stoichiometric ratio.
[0031] 2. The ZrO(NO3)2 and Y(NO3)3 weighed above were stirred and dissolved in deionized water. Then, NH4NbO(C2O4)2 and La(NO3)3 weighed were added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. After drying, a solid polymer resin was obtained.
[0032] 3. The above solid polymer resin is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 900-1500℃ for 3-10 hours to obtain xLaNbO4-YSZ composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0033] The 3YSZ is 3 mol% Y2O3-stabilized ZrO2, and the 8YSZ is 8 mol% Y2O3-stabilized ZrO2.
[0034] Furthermore, in step two, the ratio of the number of moles of citric acid to the total number of moles of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5-10% of the total volume of the final product solution.
[0035] Furthermore, the drying process described in step two involves drying at 200–500°C.
[0036] Furthermore, in step three, after ball milling and drying, the product is compressed into tablets: anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-48h. Then, it is dried at 50-100℃ for 12-48h and compressed into tablets using a tablet press.
[0037] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0038] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, α and β are all 0, weigh Sr(NO3)2, Ti[OCH(CH3)2]4, NH4NbO(C2O4)2 and La(NO3)3 according to the stoichiometric ratio;
[0039] 2. The weighed Sr(NO3)2 was dissolved in deionized water by stirring. HNO3 was added to make the pH of the solution 0.8-1.2. Then, the weighed Ti[OCH(CH3)2]4, NH4NbO(C2O4)2 and La(NO3)3 were added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. The precursor gel was obtained by drying.
[0040] 3. The above-mentioned precursor gel is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles, which are then ball-milled, dried, and pressed into sheets. The sheets are then placed in a muffle furnace under a hydrogen-argon mixed atmosphere and calcined at 900-1500℃ for 3-10 hours to obtain xLaNbO4-SrTiO3 composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0041] Furthermore, in step two, the ratio of the number of moles of citric acid to the total number of moles of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5-10% of the total volume of the final product solution.
[0042] Furthermore, the drying process described in step two involves drying at 200–500°C.
[0043] Furthermore, in step three, after ball milling and drying, the product is compressed into tablets: anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-72h. Then, it is dried at 50-100℃ for 12-48h and compressed into tablets using a tablet press.
[0044] The present invention has the following advantages and beneficial effects:
[0045] 1. Grain boundary resistance (R) gbThe addition of LaNbO4 significantly reduces the grain boundary resistance of several solid electrolyte materials. This is because LaNbO4 improves the contact between grains in solid electrolyte materials, reduces the generation and diffusion of microcracks, and lowers the content of amorphous phases. In ceramic materials, amorphous phase regions may exist at grain boundaries. These regions typically have higher resistance than the crystalline phase. The addition of LaNbO4 promotes the transformation of amorphous phases to crystalline phases at grain boundaries, reducing the content of amorphous phases. This helps to improve the conductivity of grain boundaries. For example, in the solid electrolyte material LLT, the grain boundaries are mainly amorphous. Amorphous regions typically have high resistance because their atoms are randomly arranged, which may hinder the transport of charge carriers (such as ions or electrons). After modification by adding LaNbO4, the grain boundaries of LLT become crystalline and have the same structure as the main phase (i.e., the interior of LLT grains). Crystalline regions possess a more ordered atomic arrangement, which facilitates charge carrier transport. The transition from amorphous to crystalline states is typically associated with reduced grain boundary resistance because the more ordered atomic arrangement at crystalline grain boundaries provides a more continuous transport path, reducing charge carrier scattering and trapping at the grain boundaries. Reduced grain boundary resistance contributes to improved overall material conductivity, as charge carriers can pass through the grain boundaries more efficiently, thus enhancing the material's electronic or ionic conductivity. Furthermore, it reduces grain boundary width, which refers to the size of the contact area between grains. LaNbO4 modification makes the grain boundaries finer and more compact, meaning a smaller proportion of the volume occupied by grain boundaries, thus mitigating their negative impact on overall conductivity. Finally, it increases grain boundary density, which refers to the number of grain boundaries per unit area. Increased grain boundary density likely means denser grain boundaries, reducing porosity and microcracks within them, which facilitates electron or ion transport, thereby improving the material's conductivity. In summary, grain boundary resistance is one of the main obstacles to electron or ion transport in polycrystalline ceramics, and reducing R... gb It can significantly improve the overall conductivity of solid electrolyte materials.
[0046] 2. Mitigation of thermal expansion anisotropy: Thermal expansion anisotropy refers to the inconsistent thermal expansion behavior of materials in different directions. In polycrystalline ceramics, grains usually have different orientations. When the material is heated or cooled, if the coefficient of thermal expansion (TEC) of the grains in different directions is different, it may cause problems in the contact between grains, which in turn can lead to microcracks, increase grain boundary resistance, and affect the overall electrical conductivity of the material. In solid electrolyte materials with anisotropic thermal expansion, such as NZSP and LATP, the introduction of LaNbO4 helps alleviate the degradation of intergranular contact caused by thermal expansion anisotropy, thereby reducing grain boundary cracks. Specifically, LaNbO4 forms a thin film between grains. In NZSP, Nb is significantly enriched at the grain boundaries, while La is slightly enriched, indicating that LaNbO4 may form a thin film at the grain boundaries. This film helps to establish better contact between grains with different orientations. Because the LaNbO4-modified material has better intergranular contact, the stress distribution between grains is more uniform during thermal cycling, reducing microcracks caused by thermal expansion mismatch. The reduction of microcracks and the improvement of intergranular contact can directly reduce grain boundary resistance, making the transport of electrons or ions at the grain boundaries smoother. In addition, the addition of LaNbO4 improves the material's adaptability to temperature changes and reduces performance degradation caused by temperature cycling.
[0047] 3. Formation of Intermediate Phases: Intermediate phases refer to the third phase existing between the main phases in multiphase materials, especially composite materials. In ceramic materials, intermediate phases may form at grain boundaries. These phases can significantly affect the overall properties of the material due to their unique chemical and physical properties. During sintering, the addition of LaNbO4 may cause Nb and La elements to partially dissolve into the main crystalline phase of the ceramic, forming a solid solution. A solid solution is a solid solution in which two or more components are uniformly distributed in the crystal lattice. Such a solid solution may change the electronic structure and chemical stability of the grain boundaries, thereby affecting the electrical conductivity. LaNbO4 may also form independent secondary phases at grain boundaries, i.e., independent phases that are not immiscible with the main crystalline phase. These secondary phases may have lower resistivity, thus improving the resistivity at the grain boundaries. The formation of mesophases can provide more efficient charge transport paths and may reduce grain boundary resistance because these phases may have higher ionic or electronic conductivity. Mesophases may also enhance grain boundary stability, making them more stable under temperature changes or other external conditions, which helps reduce performance loss caused by grain boundary degradation. The formation of mesophases may also change the microstructure of grain boundaries, such as by refining grains and adjusting the contact mode between grains, thus affecting the conductivity of the material. The formation of mesophases may also reduce defects at grain boundaries, such as vacancies, microcracks, or other discontinuities, which are important factors determining the magnitude of interfacial resistance. Finally, the formation of mesophases may also affect the thermodynamics and kinetics of the sintering process, changing the densification and grain growth behavior of the material, thereby affecting the conductivity of solid electrolyte materials.
[0048] In summary, the LaNbO4 additive in this invention improves grain boundary properties, alleviates thermal expansion mismatch, and forms a favorable intermediate phase, resulting in a solid electrolyte material with high ionic conductivity at room temperature.
[0049] 4. The high ionic conductivity of the conductive ceramic additive / solid electrolyte composite material prepared in this invention proves that the introduction of LaNbO4 additive effectively improves the actual room-temperature ionic conductivity of the solid electrolyte. For example, the LaNbO4-NZSP solid electrolyte composite material prepared by adding an additional 2 mol% of LaNbO4 has an ionic conductivity of 9.3 × 10⁻⁶ at 25 °C. -3 Scm -1 The solid electrolyte NZSP without the addition of LaNbO4 exhibits an ionic conductivity of only 5.2 × 10⁻⁶ at 25 °C. -3 Scm -1 The LaNbO4-LATP solid electrolyte composite material prepared by adding an additional 3 mol% of LaNbO4 exhibits an ionic conductivity of 2.1 × 10⁻⁶ at 25 °C. -3 S cm -1The solid electrolyte LATP without the addition of LaNbO4 has an ionic conductivity of only 9.5 × 10⁻⁶ at 25 °C. -4 Scm -1 These data demonstrate that the introduction of LaNbO4 additive in this invention improves the ionic conductivity of solid electrolyte materials, which helps to accelerate the rapid development of solid-state battery energy storage technology.
[0050] 5. The conductive ceramic additive / solid electrolyte composite material prepared by this invention is a solid electrolyte material with high room temperature ionic conductivity, which can be used to prepare all-solid-state batteries. The preparation process of this invention is simple and the manufacturing cost is low, which can be used for the large-scale production of solid electrolyte materials.
[0051] This invention is applicable to the preparation of conductive ceramic additive / solid electrolyte composite materials. Attached Figure Description
[0052] Figure 1 Impedance spectra and activation energy diagrams of the original samples and the samples modified with LaNbO4 in Examples 1-5 are shown. Part a is the impedance spectrum measured using high frequency (HF) and normal frequency (NF) impedance spectra, and part b is the Arrhenius plot of the total conductivity and bulk conductivity of the original samples and the samples modified with LaNbO4.
[0053] Figure 2 Part a is a scanning electron microscope (SEM) image of the original sample NZSP from Example 1, and part b is a scanning electron microscope (SEM) image of the sample LaNbO4-NZSP after modification with LaNbO4.
[0054] Figure 3 Part c is a scanning electron microscope image of the original sample LATP from Example 2, and part d is a scanning electron microscope image of the sample LaNbO4-LATP after modification with LaNbO4.
[0055] Figure 4 The images show scanning transmission electron microscopy (STEM) images and energy dispersive spectroscopy (EDS) spectra of the original sample NZSP and the sample LaNbO4-NZSP modified with LaNbO4 in Example 1.
[0056] Figure 5 The images are scanning transmission electron microscope (STEM) images of the original samples and the samples modified with LaNbO4 in Examples 3-5. Part a shows the STEM images of the original LLT and LaNbO4-LLT, part b shows the STEM images of the original 8YSZ and LaNbO4-8YSZ, and part c shows the STEM images of the original SrTiO3 and LaNbO4-SrTiO3. Detailed Implementation
[0057] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.
[0058] Specific implementation method one: The conductive ceramic additive / solid electrolyte composite material of this implementation method has the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, wherein 0.5mol%≤x≤3mol%, and only one of y, z, α, β and γ is not 0;
[0059] The NZSP is Na d Zr e Si f P g O 12 Where d, e, f, and g are all non-zero; the LATP mentioned is Li a Al b Ti c P3O 12 Where a, b, and d are all non-zero; the LLT mentioned is Li m La n TiO3, wherein m and n are both non-zero; the 8YSZ is 8 mol% Y2O3-stabilized ZrO2, and the 3YSZ is 3 mol% Y2O3-stabilized ZrO2.
[0060] This embodiment describes the application of conductive ceramic additives / solid electrolyte composite materials in conductive ceramics and in solid-state batteries, including lithium-ion batteries, zinc-ion batteries, sodium-ion batteries, solid oxide fuel cells, and other solid-state batteries, in electrolytes and other aspects.
[0061] Specific Implementation Method Two: The preparation method of the conductive ceramic additive / solid electrolyte composite material in this embodiment is implemented according to the following steps:
[0062] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and z, α, β and γ are all 0, weigh NaNO3, ZrO(NO3)2, NH4NbO(C2O4)2, La(NO3)3, Si(OCH2CH3)4 and NH4H2PO4 according to the stoichiometric ratio;
[0063] 2. The NaNO3 and ZrO(NO3)2 weighed above were dissolved in deionized water by stirring. Then, NH4NbO(C2O4)2 and La(NO3)3 weighed were added in sequence and stirred until the solution was clear. Then, Si(OCH2CH3)4 and NH4H2PO4 weighed were added and stirred to obtain a gel-like solution. The solution was dried to obtain a dry gel.
[0064] 3. The above-mentioned dry gel is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 1000-1500℃ for 3-10 hours to obtain xLaNbO4-NZSP composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0065] Where NZSP is Na d Zr e Si f P g O 12 , where d, e, f, and g are all non-zero.
[0066] In this embodiment, the xLaNbO4-NZSP composite material was prepared using a solution-assisted solid-phase reaction method.
[0067] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 2 in that the drying in step 2 is carried out at 50–100°C. Other steps and parameters are the same as in Specific Implementation Method 2.
[0068] Specific Implementation Method Four: This implementation method differs from Specific Implementation Method Two in that, in step three, after ball milling and drying, the tablets are compressed as follows: Anhydrous ethanol is added to the precursor powder particles at a mass-to-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-48 hours. Then, it is dried at 50-100℃ for 12-48 hours and finally compressed into tablets using a tablet press. Other steps and parameters are the same as in Specific Implementation Method Two.
[0069] Specific Implementation Method 5: The preparation method of the conductive ceramic additive / solid electrolyte composite material in this embodiment is implemented according to the following steps:
[0070] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, α, β and γ are all 0, weigh LiNO3, Al(NO3)3, NH4NbO(C2O4)2, La(NO3)3, Ti[OCH(CH3)2]4 and NH4H2PO4 according to the stoichiometric ratio;
[0071] 2. The weighed LiNO3 and Al(NO3)3 were dissolved in deionized water by stirring. Then, the weighed NH4NbO(C2O4)2 and La(NO3)3 were added and stirred until dissolved. HNO3 was then added to adjust the pH of the solution to 0.8-1.2. Finally, the weighed Ti[OCH(CH3)2]4 and NH4H2PO4 were added and stirred to obtain the final product solution. After drying, a rough solid powder was obtained.
[0072] 3. The above-mentioned rough solid powder is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 900-1500℃ for 3-10 hours to obtain xLaNbO4-LATP composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0073] Where LATP is Li a Al b Ti c P3O 12 , where a, b, and d are all non-zero.
[0074] In this embodiment, the xLaNbO4-LATP composite material is prepared by solution-assisted solid-phase reaction.
[0075] Specific Implementation Method Six: This implementation method differs from Specific Implementation Method Five in that the drying in step two is carried out at 50–100°C. Other steps and parameters are the same as in Specific Implementation Method Five.
[0076] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Method Five in that, in step three, after ball milling and drying, the tablets are compressed as follows: Anhydrous ethanol is added to the precursor powder particles at a mass-to-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-48 hours. Then, it is dried at 50-100℃ for 12-48 hours and finally compressed into tablets using a tablet press. Other steps and parameters are the same as in Specific Implementation Method Five.
[0077] Specific Implementation Method Eight: The preparation method of the conductive ceramic additive / solid electrolyte composite material in this embodiment is implemented according to the following steps:
[0078] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, β and γ are all 0, weigh LiNO3, La(NO3)3, Ti[OCH(CH3)2]4, La2O3 and Nb2O5 according to the stoichiometric ratio;
[0079] 2. The weighed LiNO3 and La(NO3)3 were stirred and dissolved in deionized water. HNO3 was added to make the pH of the solution 0.8-1.2. Then, the weighed Ti[OCH(CH3)2]4 was added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. After drying, a solid polymer resin was obtained.
[0080] 3. The above solid polymer resin is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles. Then, weighed La2O3 and Nb2O5 are added, and after ball milling and drying, the mixture is pressed into sheets. Then, it is placed in a muffle furnace and calcined at 900-1500℃ for 3-10 hours to obtain xLaNbO4-LLT composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0081] Where LLT is Li m La n TiO3, where neither m nor n is 0.
[0082] In this embodiment, the xLaNbO4-LLT composite material was prepared by sol-gel esterification.
[0083] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Method Eight in that, in step two, the ratio of the molar amount of citric acid to the total molar amount of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5-10% of the total volume of the final product solution. Other steps and parameters are the same as in Specific Implementation Method Eight.
[0084] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Method Eight in that the drying in step two is carried out at 200–500°C. Other steps and parameters are the same as in Specific Implementation Method Eight.
[0085] Specific Implementation Method Eleven: This implementation method differs from Specific Implementation Method Eight in that, in step three, after ball milling and drying, the tablets are compressed as follows: Anhydrous ethanol is added to the precursor powder particles at a mass-to-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-72 hours. Then, it is dried at 50-100℃ for 12-48 hours, and finally compressed into tablets using a tablet press. Other steps and parameters are the same as in Specific Implementation Method Eight.
[0086] Specific Implementation Method Twelve: The preparation method of the conductive ceramic additive / solid electrolyte composite material in this embodiment is carried out according to the following steps:
[0087] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, α and γ are all 0, weigh ZrO(NO3)2, Y(NO3)3, NH4NbO(C2O4)2 and La(NO3)3 according to the stoichiometric ratio.
[0088] 2. The ZrO(NO3)2 and Y(NO3)3 weighed above were stirred and dissolved in deionized water. Then, NH4NbO(C2O4)2 and La(NO3)3 weighed were added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. After drying, a solid polymer resin was obtained.
[0089] 3. The above solid polymer resin is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 900-1500℃ for 3-10 hours to obtain xLaNbO4-YSZ composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0090] The 3YSZ is 3 mol% Y2O3-stabilized ZrO2, and the 8YSZ is 8 mol% Y2O3-stabilized ZrO2.
[0091] In this embodiment, the xLaNbO4-YSZ composite material was prepared by sol-gel esterification.
[0092] Specific Implementation Method Thirteen: This implementation method differs from Specific Implementation Method Twelve in that, in step two, the ratio of the molar amount of citric acid to the total molar amount of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5-10% of the total volume of the final product solution. Other steps and parameters are the same as in Specific Implementation Method Twelve.
[0093] Specific Implementation Method Fourteen: This implementation method differs from Specific Implementation Method Twelve in that the drying in step two is carried out at 200–500°C. Other steps and parameters are the same as in Specific Implementation Method Twelve.
[0094] Specific Implementation Method Fifteen: This implementation method differs from Specific Implementation Method Twelve in that, in step three, after ball milling and drying, the tablets are compressed as follows: Anhydrous ethanol is added to the precursor powder particles at a mass-to-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-48 hours. Then, it is dried at 50-100℃ for 12-48 hours and finally compressed into tablets using a tablet press. Other steps and parameters are the same as in Specific Implementation Method Twelve.
[0095] Specific Implementation Method Sixteen: The preparation method of the conductive ceramic additive / solid electrolyte composite material in this embodiment is implemented according to the following steps:
[0096] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, α and β are all 0, weigh Sr(NO3)2, Ti[OCH(CH3)2]4, NH4NbO(C2O4)2 and La(NO3)3 according to the stoichiometric ratio;
[0097] 2. The weighed Sr(NO3)2 was dissolved in deionized water by stirring. HNO3 was added to make the pH of the solution 0.8-1.2. Then, the weighed Ti[OCH(CH3)2]4, NH4NbO(C2O4)2 and La(NO3)3 were added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. The precursor gel was obtained by drying.
[0098] 3. The above-mentioned precursor gel is heat-treated at 500-1000℃ for 1-5 hours to obtain precursor powder particles, which are then ball-milled, dried, and pressed into sheets. The sheets are then placed in a muffle furnace under a hydrogen-argon mixed atmosphere and calcined at 900-1500℃ for 3-10 hours to obtain xLaNbO4-SrTiO3 composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0099] In this embodiment, the xLaNbO4-YSZ composite material was prepared by sol-gel esterification.
[0100] The hydrogen-argon mixed atmosphere described in this embodiment has a volume ratio of hydrogen to argon of 1:1.
[0101] Specific Implementation Method Seventeen: This implementation method differs from Specific Implementation Method Sixteen in that, in step two, the ratio of the molar amount of citric acid to the total molar amount of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5-10% of the total volume of the final product solution. Other steps and parameters are the same as in Specific Implementation Method Sixteen.
[0102] Specific Implementation Method Eighteen: This implementation method differs from Specific Implementation Method Sixteen in that the drying in step two is carried out at 200–500°C. Other steps and parameters are the same as in Specific Implementation Method Sixteen.
[0103] Specific Implementation Method Nineteen: This implementation method differs from Specific Implementation Method Sixteen in that, in step three, after ball milling and drying, the tablets are compressed as follows: Anhydrous ethanol is added to the precursor powder particles at a mass-to-volume ratio of 1g:(5-10)ml, and the mixture is wet-milled in a ball mill for 12-72 hours. Then, it is dried at 50-100℃ for 12-48 hours, and finally compressed into tablets using a tablet press. Other steps and parameters are the same as in Specific Implementation Method Sixteen.
[0104] The beneficial effects of the present invention are verified through the following embodiments:
[0105] Unless otherwise specified, the reagents, instruments and equipment used in this invention are all conventional reagents, instruments and equipment in the art.
[0106] Example 1:
[0107] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0108] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where x=2mol%, and z, α, β and γ are all 0, weigh NaNO3, ZrO(NO3)2, NH4NbO(C2O4)2, La(NO3)3, Si(OCH2CH3)4 and NH4H2PO4 according to the stoichiometric ratio;
[0109] 2. The NaNO3 and ZrO(NO3)2 weighed above were dissolved in deionized water by stirring. Then, NH4NbO(C2O4)2 and La(NO3)3 weighed were added in sequence and stirred until the solution was clear. Then, Si(OCH2CH3)4 and NH4H2PO4 weighed were added and stirred to obtain a gel-like solution. The solution was dried to obtain a dry gel.
[0110] 3. The above-mentioned dry gel was heat-treated at 800℃ for 3 hours to obtain precursor powder particles, which were then ball-milled and dried and pressed into sheets. The sheets were then placed in a muffle furnace and calcined at 1260℃ for 5 hours to obtain xLaNbO4-NZSP composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0111] Where NZSP is Na 3.4 Zr2Si 2.4 P 0.6 O 12 .
[0112] The drying process described in step two of this embodiment involves drying at 85°C.
[0113] In step three of this embodiment, after ball milling and drying, the product is compressed into tablets: Anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:5ml, and the mixture is wet-milled in a ball mill for 48 hours. Then, it is dried at 70°C for 12 hours and compressed into tablets using a tablet press.
[0114] The xLaNbO4-NZSP composite material prepared in this embodiment is a sheet-like solid electrolyte composite material. AC impedance testing revealed that its ionic conductivity at 25℃ is 9.3 × 10⁻⁶. -3 S cm -1 .
[0115] Example 2:
[0116] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0117] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where x = 3 mol%, and y, α, β and γ are all 0, weigh LiNO3, Al(NO3)3, NH4NbO(C2O4)2, La(NO3)3, Ti[OCH(CH3)2]4 and NH4H2PO4 according to the stoichiometric ratio;
[0118] 2. The weighed LiNO3 and Al(NO3)3 were dissolved in deionized water by stirring. Then, the weighed NH4NbO(C2O4)2 and La(NO3)3 were added and stirred until dissolved. HNO3 was then added to adjust the pH of the solution to 0.8-1.2. Finally, the weighed Ti[OCH(CH3)2]4 and NH4H2PO4 were added and stirred to obtain the final product solution. After drying, a rough solid powder was obtained.
[0119] 3. The above-mentioned rough solid powder is heat-treated at 650℃ for 3 hours to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 950℃ for 5 hours to obtain xLaNbO4-LATP composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0120] Where LATP is Li 1.5 Al 0.5 Ti 1.5 P3O 12 .
[0121] The drying process described in step two of this embodiment involves drying at 85°C.
[0122] In step three of this embodiment, after ball milling and drying, the product is compressed into tablets: Anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:5ml, and the mixture is wet-milled in a ball mill for 48 hours. Then, it is dried at 700℃ for 48 hours and compressed into tablets using a tablet press.
[0123] The xLaNbO4-LATP composite material prepared in this embodiment is a sheet-like solid electrolyte composite material. AC impedance testing revealed that its ionic conductivity at 25℃ is 2.1 × 10⁻⁶. -3 S cm -1 .
[0124] Example 3:
[0125] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0126] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where x=2mol%, and y, z, β and γ are all 0, weigh LiNO3, La(NO3)3, Ti[OCH(CH3)2]4, La2O3 and Nb2O5 according to the stoichiometric ratio;
[0127] 2. The weighed LiNO3 and La(NO3)3 were stirred and dissolved in deionized water. HNO3 was added to make the pH of the solution 0.8-1.2. Then, the weighed Ti[OCH(CH3)2]4 was added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. After drying, a solid polymer resin was obtained.
[0128] 3. The above solid polymer resin is heat-treated at 800℃ for 3h to obtain precursor powder particles. Then, weighed La2O3 and Nb2O5 are added, and after ball milling and drying, the mixture is pressed into sheets and then placed in a muffle furnace and calcined at 1325℃ for 5h to obtain xLaNbO4-LLT composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0129] Where LLT is Li 0.34 La 0.56 TiO3.
[0130] In step two of this embodiment, the ratio of the number of moles of citric acid to the total number of moles of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5% of the total volume of the final product solution.
[0131] The drying process described in step two of this embodiment involves drying at 300°C.
[0132] In step three of this embodiment, after ball milling and drying, the product is compressed into tablets: Anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:5ml, and the mixture is wet-milled in a ball mill for 72 hours. Then, it is dried at 70°C for 48 hours and compressed into tablets using a tablet press.
[0133] The xLaNbO4-LLT composite material prepared in this embodiment is a sheet-like solid electrolyte composite material. AC impedance testing revealed that its ionic conductivity at 25℃ is 1.3 × 10⁻⁶. -4 S cm -1 .
[0134] Example 4:
[0135] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0136] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ / γSrTiO3, where x = 0.5 mol%, and y, z, α, and γ are all 0, weigh ZrO(NO3)2, Y(NO3)3, NH4NbO(C2O4)2, and La(NO3)3 according to the stoichiometric ratio; wherein 8YSZ is 8 mol% Y2O3-stabilized ZrO2;
[0137] 2. The ZrO(NO3)2 and Y(NO3)3 weighed above were stirred and dissolved in deionized water. Then, NH4NbO(C2O4)2 and La(NO3)3 weighed were added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. After drying, a solid polymer resin was obtained.
[0138] 3. The above solid polymer resin is heat-treated at 900℃ for 3 hours to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 1400℃ for 5 hours to obtain xLaNbO4-β8YSZ composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0139] In step two of this embodiment, the ratio of the number of moles of citric acid to the total number of moles of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5% of the total volume of the final product solution.
[0140] The drying process described in step two of this embodiment involves drying at 300°C.
[0141] In step three of this embodiment, after ball milling and drying, the product is compressed into tablets: Anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:5ml, and the mixture is wet-milled in a ball mill for 48 hours. Then, it is dried at 70°C for 48 hours and compressed into tablets using a tablet press.
[0142] The xLaNbO4-8YSZ composite material prepared in this embodiment is a sheet-like solid electrolyte composite material. AC impedance testing was performed on it, and the calculated ionic conductivity at 25℃ was 1.4 × 10⁻⁶. -5 S cm -1 .
[0143] Example 5:
[0144] A method for preparing conductive ceramic additive / solid electrolyte composite materials, which is carried out according to the following steps:
[0145] I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where x=1mol%, and y, z, α and β are all 0, weigh Sr(NO3)2, Ti[OCH(CH3)2]4, NH4NbO(C2O4)2 and La(NO3)3 according to the stoichiometric ratio;
[0146] 2. The weighed Sr(NO3)2 was dissolved in deionized water by stirring. HNO3 was added to make the pH of the solution 0.8-1.2. Then, the weighed Ti[OCH(CH3)2]4, NH4NbO(C2O4)2 and La(NO3)3 were added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. The precursor gel was obtained by drying.
[0147] 3. The precursor gel was heat-treated at 900℃ for 3 hours to obtain precursor powder particles, which were then ball-milled, dried and pressed into sheets. The sheets were then placed in a muffle furnace under a hydrogen-argon mixed atmosphere and calcined at 1400℃ for 5 hours to obtain xLaNbO4-SrTiO3 composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.
[0148] In step two of this embodiment, the ratio of the number of moles of citric acid to the total number of moles of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5% of the total volume of the final product solution.
[0149] The drying process described in step two of this embodiment involves drying at 300°C.
[0150] In step three of this embodiment, after ball milling and drying, the product is compressed into tablets: Anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:5ml, and the mixture is wet-milled in a ball mill for 48 hours. Then, it is dried at 70°C for 48 hours and compressed into tablets using a tablet press.
[0151] The xLaNbO4-SrTiO3 composite material prepared in this embodiment is a sheet-like solid electrolyte composite material. AC impedance testing revealed that its ionic conductivity at 25℃ is 3.1 × 10⁻⁶. -4 S cm -1 .
[0152] Table 1 shows the basic information of the original samples and the samples modified with LaNbO4 (i.e. the prepared products) in Examples 1-5, including the sample name, the amount of LaNbO4 added, the preparation method, the theoretical density, the sintering temperature, and the relative density of the original sample and the modified sample.
[0153] Table 1
[0154]
[0155] Table 2 shows the conductivity data and activation energy (E) of the original samples and the LaNbO4-modified samples from Examples 1-5. a Conductivity data typically include volumetric conductivity (σ). bulk ) and total conductivity (σ total The activation energy refers to the energy required for the electrical conductivity of a material to change with temperature; therefore, adding an appropriate amount of LaNbO4 can significantly improve the NZSP (Na+) conductivity. 3.4 Zr2Si 2.4 P 0.6 O 12 LATP (Li 1.5 Al 0.5 Ti 1.5 P3O 12 LLT (Li) 0.34 La 0.56 Ionic conductivity of TiO3), 8YSZ (8 mol% Y2O3-stabilized ZrO2), and SrTiO3 at room temperature.
[0156] Table 2
[0157]
[0158] Figure 1 The impedance spectra and activation energy diagrams of the original samples and the samples modified with LaNbO4 in Examples 1-5 are shown. Part a is the measurement using high frequency (HF) and normal frequency (NF) impedance spectroscopy instruments. Part b is the Arrhenius plot of the total conductivity and bulk conductivity of the original samples and the samples modified with LaNbO4, used to determine the relationship between the activation energy and conductivity of the materials as a function of temperature. As can be seen from the figures, the conductivity of the samples with additives is greatly improved, especially the grain boundary conductivity.
[0159] Figure 2 The images show scanning electron microscope (SEM) images of the original NZSP sample (part a) and the LaNbO4-NZSP sample (part b) modified with LaNbO4 in Example 1. As can be seen from the images, the sample without additives is not easy to sinter into a dense state and has large pores, while the sample with additives has good grain boundary contact and is easy to sinter into a dense state.
[0160] Figure 3 The images show scanning electron microscope (SEM) images of the original sample LATP (part c) and the sample LaNbO4-LATP (part d) modified with LaNbO4 in Example 2. As can be seen from the images, the sample without additives is not easy to sinter densely and has large pores, while the sample with additives has good grain boundary contact and is easy to sinter densely.
[0161] Figure 4 The images show scanning transmission electron microscopy (STEM) images and energy dispersive spectroscopy (EDS) spectra of the original NZSP sample and the LaNbO4-NZSP sample modified with LaNbO4. The images show significant Nb enrichment at the grain boundaries of NZSP, while La is slightly enriched. This indicates that LaNbO4 may have formed a thin film at the grain boundaries. This film helps establish better contact between grains with different orientations. Because the LaNbO4-modified material has better intergranular contact, the stress distribution between grains is more uniform during thermal cycling, reducing microcracks caused by thermal expansion mismatch. The reduced microcracks and improved intergranular contact directly lower the grain boundary resistance, making the transport of electrons or ions at the grain boundaries smoother. Furthermore, the addition of LaNbO4 improves the material's adaptability to temperature changes and reduces performance degradation caused by temperature cycling.
[0162] Figure 5 The images show scanning transmission electron microscopy (STEM) images of the original samples and the samples modified with LaNbO4 in Examples 3-5. Part a represents the original LLT and LaNbO4-LLT, part b represents the original 8YSZ (8% mol Y2O3 stabilized) and LaNbO4-8YSZ, and part c represents the original SrTiO3 and LaNbO4-SrTiO3. As can be seen from the images, the addition of additives significantly improves the contact between grains in the solid electrolyte material, reduces the generation and diffusion of microcracks, and lowers the content of amorphous phases. The good interfacial contact greatly improves the grain boundary conductivity, thereby improving the overall conductivity of the electrolyte.
[0163] Although the present invention has been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many modifications under the guidance of the present invention without departing from the spirit of the present invention, and these modifications are all within the protection scope of the present invention.
Claims
1. A method for preparing a conductive ceramic additive / solid electrolyte composite material, characterized in that... It proceeds in the following steps: I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and z, α, β and γ are all 0, weigh NaNO3, ZrO(NO3)2, NH4NbO(C2O4)2, La(NO3)3, Si(OCH2CH3)4 and NH4H2PO4 according to the stoichiometric ratio; 2. The NaNO3 and ZrO(NO3)2 weighed above were dissolved in deionized water by stirring. Then, NH4NbO(C2O4)2 and La(NO3)3 weighed were added in sequence and stirred until the solution was clear. Then, Si(OCH2CH3)4 and NH4H2PO4 weighed were added and stirred to obtain a gel-like solution. The solution was dried to obtain a dry gel.
3. The above-mentioned dry gel is heat-treated at 500~1000℃ for 1~5h to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 1000~1500℃ for 3~10h to obtain xLaNbO4-NZSP composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material. Where NZSP is Na d Zr e Si f P g O 12 , where d, e, f, and g are all non-zero.
2. The preparation method of the conductive ceramic additive / solid electrolyte composite material according to claim 1, characterized in that... The drying process described in step two involves drying at 50~100℃.
3. The preparation method of the conductive ceramic additive / solid electrolyte composite material according to claim 1, characterized in that... The ball milling and drying process described in step three is followed by tableting: Anhydrous ethanol is added to the precursor powder particles at a mass-volume ratio of 1g:(5~10)ml, and the mixture is wet-milled in a ball mill for 12~48h. Then, it is dried at 50~100℃ for 12~48h and finally compressed into tablets using a tablet press.
4. A method for preparing conductive ceramic additive / solid electrolyte composite material, characterized in that... It proceeds in the following steps: I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, α, β and γ are all 0, weigh LiNO3, Al(NO3)3, NH4NbO(C2O4)2, La(NO3)3, Ti[OCH(CH3)2]4 and NH4H2PO4 according to the stoichiometric ratio; 2. The weighed LiNO3 and Al(NO3)3 were dissolved in deionized water by stirring. Then, the weighed NH4NbO(C2O4)2 and La(NO3)3 were added and stirred until dissolved. HNO3 was then added to adjust the pH of the solution to 0.8~1.
2. Finally, the weighed Ti[OCH(CH3)2]4 and NH4H2PO4 were added and stirred to obtain the final product solution. After drying, a rough solid powder was obtained.
3. The above-mentioned rough solid powder is heat-treated at 500~1000℃ for 1~5h to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 900~1500℃ for 3~10h to obtain xLaNbO4-LATP composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material. Where LATP is Li a Al b Ti c P3O 12 , where a, b, and c are all non-zero.
5. A method for preparing a conductive ceramic additive / solid electrolyte composite material, characterized in that... It proceeds in the following steps: I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, β and γ are all 0, weigh LiNO3, La(NO3)3, Ti[OCH(CH3)2]4, La2O3 and Nb2O5 according to the stoichiometric ratio; 2. The weighed LiNO3 and La(NO3)3 were stirred and dissolved in deionized water. HNO3 was added to make the pH of the solution 0.8~1.
2. Then, the weighed Ti[OCH(CH3)2]4 was added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. After drying, a solid polymer resin was obtained.
3. The above solid polymer resin is heat-treated at 500~1000℃ for 1~5h to obtain precursor powder particles. Then, weighed La2O3 and Nb2O5 are added, and after ball milling and drying, the mixture is pressed into sheets. Then, it is placed in a muffle furnace and calcined at 900~1500℃ for 3~10h to obtain xLaNbO4-LLT composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material. Where LLT is Li m La n TiO3, where neither m nor n is 0.
6. The method for preparing the conductive ceramic additive / solid electrolyte composite material according to claim 5, characterized in that... In step two, the ratio of the number of moles of citric acid to the total number of moles of metal ions in the final product solution is 2:1; the amount of ethylene glycol added accounts for 5-10% of the total volume of the final product solution.
7. The method for preparing the conductive ceramic additive / solid electrolyte composite material according to claim 5, characterized in that... The drying process described in step two involves drying at 200~500℃.
8. A method for preparing a conductive ceramic additive / solid electrolyte composite material, characterized in that... It proceeds in the following steps: I. Weigh ZrO(NO3)2, Y(NO3)3, NH4NbO(C2O4)2 and La(NO3)3 according to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, α and γ are all 0, according to the stoichiometric ratio.
2. The ZrO(NO3)2 and Y(NO3)3 weighed above were stirred and dissolved in deionized water. Then, NH4NbO(C2O4)2 and La(NO3)3 weighed were added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. After drying, a solid polymer resin was obtained.
3. The above solid polymer resin is heat-treated at 500~1000℃ for 1~5h to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace and calcined at 900~1500℃ for 3~10h to obtain xLaNbO4-YSZ composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material. The 3YSZ is 3 mol% Y2O3-stabilized ZrO2, and the 8YSZ is 8 mol% Y2O3-stabilized ZrO2.
9. A method for preparing conductive ceramic additive / solid electrolyte composite material, characterized in that... It proceeds in the following steps: I. According to the chemical formula xLaNbO4-yNZSP / zLATP / αLLT / β8YSZ or β3YSZ / γSrTiO3, where 0.5mol%≤x≤3mol%, and y, z, α and β are all 0, weigh Sr(NO3)2, Ti[OCH(CH3)2]4, NH4NbO(C2O4)2 and La(NO3)3 according to the stoichiometric ratio; 2. The weighed Sr(NO3)2 was dissolved in deionized water by stirring. HNO3 was added to make the pH of the solution 0.8~1.
2. Then, the weighed Ti[OCH(CH3)2]4, NH4NbO(C2O4)2 and La(NO3)3 were added and stirred until dissolved. Citric acid and ethylene glycol were added and stirred to obtain the final product solution. The precursor gel was obtained by drying.
3. The above-mentioned precursor gel is heat-treated at 500~1000℃ for 1~5h to obtain precursor powder particles, which are then ball-milled and dried and pressed into sheets. The sheets are then placed in a muffle furnace under a hydrogen-argon mixed atmosphere and calcined at 900~1500℃ for 3~10h to obtain xLaNbO4-SrTiO3 composite material, thus completing the preparation of the conductive ceramic additive / solid electrolyte composite material.