CN105418068B - A kind of niobate glass ceramics energy storage material and its preparation method and application - Google Patents

Abstract

_The present invention _relates to a _{novel niobate - based glass - ceramic} energy storage material and its preparation method and application. ≤x≤1. Using BaCO ₃ , SrCO ₃ , NaCO ₃ , Nb ₂ O ₅ , and SiO ₂ powders as raw materials, weigh the quality of each component according to the designed chemical composition, mix them evenly through ball milling, and put them into a crucible for high-temperature melting. Quickly cast into a preheated copper mold to remove stress, and then cut into thin slices with a thickness of 1.0mm; put the glass flakes into an annealing furnace for controlled crystallization, by controlling the composition of glass raw materials and optimizing the crystallization process, the prepared Niobate glass ceramics have high energy storage density and reliability. Compared with the prior art, the method of the invention is simple, and the prepared glass-ceramic material has higher energy storage density and higher charging and discharging efficiency through experiments and tests, and is expected to be used as a new energy storage capacitor material.

Description

A niobate-based glass-ceramic energy storage material and its preparation method and application

technical field

The invention belongs to the field of dielectric energy storage materials, and in particular relates to a novel niobate-based glass ceramic energy storage material and its preparation method and application.

Background technique

In order to meet the miniaturization and lightweight requirements of pulsed power systems, the development of dielectric materials as core components is facing more challenges. How to further improve the energy storage density of dielectric materials has become the focus of research. Material workers from various countries are actively exploring and researching Dielectric material with high dielectric constant, low electrical loss and high dielectric strength. Niobate ferroelectric glass-ceramics have attracted extensive attention in this field in recent years due to their excellent dielectric properties. At present, there are mainly strontium barium niobate (SrxBa1-xNb2O6, x=0.25-0.75), lead metaniobate (PbNb ₂ O ₆ ), sodium barium niobate (Ba ₂ NaNb ₅ O ₁₅ ), potassium niobate (KNbO3), sodium niobate (NaNbO3) and other systems.

In the niobate-based glass-ceramic system, the reported higher energy storage density is mainly lead metaniobate (PbNb ₂ O ₆ )-based glass-ceramic system. Du Jun et al. prepared NaNbO ₃ by the method of controlled crystallization -PbNb ₂ O ₆ -SiO ₂ , (Pb,Sr)Nb ₂ O ₆ -NaNbO ₃ -SiO ₂ and other system glass ceramics, by optimizing the preparation process, a higher energy storage performance was obtained ([Preparation and characterization of dielectric glass -ceramics in Na ₂ O–PbO–Nb ₂ O ₅ –SiO ₂ system, Materials Letters 59(2005) 2821-2826]). However, these systems all contain lead, which is easy to volatilize at high temperatures and is harmful to the environment. It has been reported in the literature that the AF45 glass produced by SCHOTT has a very high breakdown voltage, and its breakdown voltage has reached 12MV/cm measured in the laboratory. After testing, the maximum energy storage density of AF45 glass has reached 35J/cm3 ( [Alkali-free glass as a high energy density dielectric material, Materials Letters 63 (2009) 1245-1248]), but the composition of AF45 glass is too complex, and the viscosity of the glass is too high, it is difficult to prepare under conventional conditions. Zeng et al. have effectively improved the dielectric constant of BaO-SrO-Nb ₂ O ₅ -B ₂ O ₃ system glass ceramics by doping BaF2, but the breakdown field strength of this system is only 527Kv/cm, so the energy storage density is relatively low. Low ([Effect of BaF ₂ addition on crystallization kinetics and dielectric properties of B ₂ O ₃ -Nb ₂ O ₅ -SrO-BaO glass-ceramics, J.Am.Ceram Soc, 2011,94(2):469]). In the early stage, our group used BaO-B ₂ O ₃ -Al ₂ O ₃ -SiO ₂ as the main component of the glass phase to prepare niobate ferroelectric glass ceramics ([Dielectric properties and charge–discharge behaviors in niobateglass ceramics for energy-storage applications, Journal of Alloys and Compounds 617(2014) 418–422.]), however, because the composition of the glass matrix is too complex, not only the preparation process is more complicated, but also in the crystallization process, it is easy to form many impurity phases, thus affecting the glass Energy storage properties of ceramics.

Chinese patent CN 104671665A discloses lead-free glass-ceramic with low dielectric loss and its preparation method. The composition of the glass-ceramic is: aBaO-bSrO-cNb ₂ O ₅ -dZnO-xSiO ₂ -yB ₂ O ₃ -zREO, wherein , a, b, c, d, x, y, z are molar ratios, which means the molar ratio between components, REO means rare earth oxide; and satisfy: 0≤a≤10.35, 9.97≤b≤20.70, 20.19≤c≤ 20.70, 14.80≤d≤15.50, 14.56≤x≤15.00, 27.51≤y≤28.10, 0≤z≤3.00. Select raw materials according to the composition of glass ceramics, mix them in proportion, and melt them at high temperature; quickly pour the uniformly molten glass liquid into a preheated metal mold, cool and form, and stress-relieve annealing; controllable crystallization treatment is performed on the obtained glass flakes. Can. The main crystalline phase of this system is Ba _x Sr _1-x NbO ₃ , and the glass phase is ZnO-SiO ₂ -B ₂ O ₃ . During the crystallization process, many impurity phases are easily generated, which leads to a low breakdown field strength of this series of samples. Judging from the breakdown strength reported in the patent, the breakdown strength of all samples does not exceed 200Kv/mm, which is far from It is lower than the breakdown strength value of [(Ba _1-x Sr _x ) ₂ NaNb ₅ O ₁₅ ] _0.6 -[SiO ₂ ] _0.4 involved in this patent.

Contents of the invention

The purpose of the present invention is to provide a novel niobate-based glass-ceramic energy storage material and its preparation method that improves the dielectric constant of the glass-ceramic and also improves the breakdown field strength in order to overcome the above-mentioned defects in the prior art and apply.

The purpose of the present invention can be achieved through the following technical solutions:

The niobate-based glass ceramic energy storage material has a chemical composition of [(Ba _1-x Sr _x ) ₂ NaNb ₅ O ₁₅ ] _0.6 -[SiO ₂ ] _0.4 , where 0≤x≤1.

The value range of x is preferably 0.1≤x≤0.5.

The value range of x is most preferably 0.25.

The preparation method of novel niobate-based glass-ceramic energy storage material adopts the following steps:

(1) Use analytically pure BaCO ₃ , SrCO ₃ , NaCO ₃ , Nb ₂ O ₅ , B ₂ O ₃ , Al ₂ O ₃ , and SiO ₂ powders as raw materials, and prepare materials according to the chemical composition of energy storage materials;

(2) using absolute ethanol as a dispersant, adopting agate balls and placing the above-mentioned components in a ball mill jar for ball milling, and drying the uniformly mixed slurry;

(3) Put the dried glass raw material into the crucible to melt at high temperature, then quickly pour the high-temperature melt into the preheated copper mold to obtain a transparent glass block without devitrification, and put the glass block into the retreat Stress relief annealing in furnace;

(4) Use a slicer to cut the transparent glass block into thin slices; put the glass flakes into an annealing furnace for controlled crystallization, the heating rate of the annealing furnace is 3-5°C/min, and the crystallization temperature is 800-1100°C , and the holding time is 1-3h, that is, the niobate-based glass-ceramic energy storage material is prepared.

The time for ball milling and mixing in step (2) is 10 to 20 hours.

Step (3) During the high-temperature melting process, the heating rate of the glass furnace is 1-2°C/min, and the temperature is kept at 800°C for 3 hours. The temperature of high-temperature melting is 1400-1600°C, and the time of high-temperature melting is 2-5 hours. Preheat to 500-650°C in advance, preferably 600°C; then put the glass block into the annealing furnace to relieve stress, and the stress-relief holding temperature is 500-650°C, preferably 600°C; Cool in the furnace.

When performing controlled crystallization in step (4), the heating rate of the annealing furnace is 3-5°C/min, the crystallization temperature is 800-1100°C, the holding time is 2-3h, and the furnace is cooled after the holding.

The new niobate-based glass-ceramic energy storage material can be applied in the field of energy storage capacitor materials. Compared with the prior art, the dielectric properties of the glass ceramics of the present invention are the result of the synergistic effect of glass phase and crystal phase properties. The existence of the glass phase makes the glass-ceramic have a higher breakdown field strength, and the composition and content of the crystal phase have an important influence on the dielectric constant of the material. Glass ceramics have a high breakdown field strength, how to increase the dielectric constant of the material while maintaining high withstand voltage characteristics has become a difficult research point. The present invention uses SiO ₂ as the glass phase, BaO(SrO)-Na ₂ O-Nb ₂ O ₅ as the ceramic phase, and prepares a glass block by the method of rapid quenching of the melt, and prepares it by the method of controllable crystallization after slicing Niobate ferroelectric glass ceramics, by adjusting the ratio of the glass phase to the ceramic phase, using the thermodynamic properties of the glass, and adopting an optimized crystallization process, the glass of a specific component is crystallized under certain conditions, so that the original uniform, The dense and defect-free glass phase forms a composite material containing a large number of high-permittivity ferroelectric ceramic microcrystalline phases and a uniform distribution of the glass phase. Component 6Na ₂ O-18BaO-6SrO-30Nb ₂ O ₅ -40SiO ₂ glass crystallized at 1000 ° C glass ceramic samples were tested, the dielectric constant of the sample at room temperature is 81, the breakdown field strength is 1212Kv/cm, Through calculation, its energy storage density reaches 5.27J/cm ³ .

Description of drawings

Fig. 1 is the XRD spectrum of the product prepared in Example 1-5 after crystallization at 1000°C;

Figure 2 is the XRD spectrum of the product prepared in Example 2 after crystallization at different temperatures;

Fig. 3 is the variation curve of dielectric constant with temperature after crystallization at 1000 DEG C of the product prepared in Example 1-5;

Fig. 4 shows the breakdown field strength of the products prepared in Examples 1-5 after crystallization at 1000°C;

Fig. 5 shows the activation energy and breakdown field strength of the products prepared in Examples 1-5 after crystallization at 1000°C.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example 1 (x=0)

Niobate glass ceramics with high energy storage density 6Na ₂ O-24BaO-30Nb ₂ O ₅ -40SiO ₂

(1) Using analytically pure BaCO ₃ , NaCO ₃ , Nb ₂ O ₅ , and SiO ₂ powders as raw materials, weigh the mass of each component according to the designed chemical composition 6Na ₂ O-24BaO-30Nb ₂ O ₅ -40SiO ₂ , the total mass of the sample is 80-100 grams.

(2) Select anhydrous ethanol as the dispersant, use agate balls to mill in a polytetrafluoroethylene ball mill tank at a speed of 50-60 rpm, and dry the evenly mixed slurry. The time of ball milling is 20~30h, and the ratio of ball to material during ball milling is (1.0~1.5):1.

(3) Put the dried glass raw material into the crucible for high-temperature melting, the heating rate of the high-temperature furnace is 1400° C., and the high-temperature melting time is 5 hours. Then the high-temperature melt is quickly poured into the preheated copper mold to obtain a transparent glass block without devitrification, and the glass block is placed in an annealing furnace for stress relief annealing. The preheating temperature of the copper mold is 500°C; then put the glass block into the annealing furnace to relieve stress, the stress relief holding temperature is 500°C; the holding time is 5h; after the holding is completed, the cooling method is furnace cooling.

(4) Use a slicer to cut the transparent glass block into thin slices with a thickness of 1.0 mm; put the glass thin slices into an annealing furnace for controlled crystallization, the heating rate of the annealing furnace is 3 °C/min, and the crystallization temperature is 1000 ℃, the holding time is 2 hours, and the cooling method after the holding is completed is cooling with the furnace, and finally a niobate glass ceramic sample is obtained.

The XRD spectrum of the ceramic sample prepared in this embodiment is shown in the x=0 curve in Figure 1, the dielectric properties are shown in the x=0 curve in Figure 3, and the breakdown resistance is shown in the x=0 curve in Figure 4 According to the test, the glass-ceramic sample crystallized at 1000°C has a dielectric constant of 78 at room temperature and a breakdown field strength of 1075kV/cm. According to calculation, its energy storage density reaches 3.99J/cm ³ .

Example 2 (x=0.25)

Niobate glass ceramics with high energy storage density 6Na ₂ O-18BaO-6SrO-30Nb ₂ O ₅ -40SiO ₂

(1) Using analytically pure BaCO ₃ , SrCO ₃ , NaCO ₃ , Nb ₂ O ₅ , B ₂ O ₃ , Al ₂ O ₃ , and SiO ₂ powders as raw materials, according to the designed chemical composition 6Na ₂ O-18BaO-6SrO- 30Nb ₂ O ₅ -40SiO ₂ Weigh the mass of each component, and the total mass of the sample is 80-100 grams.

(2) Select anhydrous ethanol as the dispersant, use agate balls to mill in a polytetrafluoroethylene ball mill tank at a speed of 50-60 rpm, and dry the evenly mixed slurry. The time of ball milling is 20~30h, and the ratio of ball to material during ball milling is (1.0~1.5):1.

(3) Put the dried glass raw material into the crucible for high-temperature melting, the heating rate of the high-temperature furnace is 1500° C., and the high-temperature melting time is 5 hours. Then the high-temperature melt is quickly poured into the preheated copper mold to obtain a transparent glass block without devitrification, and the glass block is placed in an annealing furnace for stress relief annealing. The preheating temperature of the copper mold is 600°C; then put the glass block into the annealing furnace to relieve the stress, the stress relief holding temperature is 600°C; the holding time is 4h; after the holding is completed, the cooling method is furnace cooling.

(4) Use a slicer to cut the transparent glass block into thin slices with a thickness of 1.0 mm; put the glass thin slices into an annealing furnace for controlled crystallization, the heating rate of the annealing furnace is 4 °C/min, and the crystallization temperature is 1000 ℃, the holding time is 2 hours, and the cooling method is furnace cooling after the holding, and finally a niobate glass ceramic sample is obtained.

The XRD spectrum of the ceramic sample prepared by the present embodiment is shown in the curve in Figure 2, the dielectric properties are shown in the curve of x=0.25 in Figure 3, and the breakdown resistance is shown in the curve of x=0.25 in Figure 4. After 1000 The glass-ceramic sample crystallized at ℃ was tested. At room temperature, the dielectric constant of the sample was 81, and the breakdown field strength was 1212kV/cm. Through calculation, the energy storage density reached 5.27J/cm ³ .

Example 3 (x=0.50)

Niobate glass ceramics with high energy storage density 6Na ₂ O-12BaO-12SrO-30Nb ₂ O ₅ -40SiO ₂

(1) Use analytically pure BaCO ₃ , SrCO ₃ , NaCO ₃ , Nb ₂ O ₅ , and SiO ₂ powders as raw materials, and weigh them according to the designed chemical composition 6Na ₂ O-12BaO-12SrO-30Nb ₂ O ₅ -40SiO ₂ The mass of each component, the total mass of the sample is 80-100 grams.

(2) Select anhydrous ethanol as the dispersant, use agate balls to mill in a polytetrafluoroethylene ball mill tank at a speed of 50-60 rpm, and dry the evenly mixed slurry. The time of ball milling is 20~30h, and the ratio of ball to material during ball milling is (1.0~1.5):1.

(3) Put the dried glass raw material into the crucible for high-temperature melting, the heating rate of the high-temperature furnace is 1600° C., and the high-temperature melting time is 2 hours. Then the high-temperature melt is quickly poured into the preheated copper mold to obtain a transparent glass block without devitrification, and the glass block is placed in an annealing furnace for stress relief annealing. The preheating temperature of the copper mold is 650°C; then put the glass block into the annealing furnace to relieve the stress, the stress relief holding temperature is 650°C, and the holding time is 3h; after the holding is completed, the cooling method is to cool with the furnace.

(4) Use a slicer to cut the transparent glass block into thin slices with a thickness of 1.0mm; put the glass thin slices into an annealing furnace for controlled crystallization, the heating rate of the annealing furnace is 5°C/min, and the crystallization temperature is 1100 ℃, the holding time is 2 hours, and the cooling method after the holding is completed is cooling with the furnace, and finally a niobate glass ceramic sample is obtained.

The XRD spectrum of the ceramic sample prepared in this embodiment is shown in the x=0.50 curve in Figure 1, the dielectric properties are shown in the x=0.50 curve in Figure 3, and the breakdown resistance is shown in the x=0.50 curve in Figure 4 According to the test, the glass-ceramic sample crystallized at 1000°C has a dielectric constant of 93 and a breakdown field strength of 963kV/cm at room temperature. According to calculation, its energy storage density reaches 3.81J/cm ³ .

Example 4 (x=0.75)

Niobate glass ceramics with high energy storage density 6Na ₂ O-6BaO-18SrO-30Nb ₂ O ₅ -40SiO ₂

(1) Use analytically pure BaCO ₃ , SrCO ₃ , NaCO ₃ , Nb ₂ O ₅ , and SiO ₂ powders as raw materials, and weigh them according to the designed chemical composition 6Na ₂ O-6BaO-18SrO-30Nb ₂ O ₅ -40SiO ₂ The mass of each component, the total mass of the sample is 80-100 grams.

(2) Select anhydrous ethanol as the dispersant, use agate balls to mill in a polytetrafluoroethylene ball mill tank at a speed of 50-60 rpm, and dry the evenly mixed slurry. The time of ball milling is 20~30h, and the ratio of ball to material during ball milling is (1.0~1.5):1.

(3) Put the dried glass raw material into the crucible for high-temperature melting, the heating rate of the high-temperature furnace is 1600° C., and the high-temperature melting time is 5 hours. Then the high-temperature melt is quickly poured into the preheated copper mold to obtain a transparent glass block without devitrification, and the glass block is placed in an annealing furnace for stress relief annealing. The copper mold is preheated at a temperature of 650°C, and then the glass block is placed in an annealing furnace to relieve stress. The stress relief holding temperature is 600°C; the holding time is 5 hours; after the holding is completed, the cooling method is furnace cooling.

(4) Use a slicer to cut the transparent glass block into thin slices with a thickness of 1.0mm; put the glass thin slices into an annealing furnace for controlled crystallization, the heating rate of the annealing furnace is 5°C/min, and the crystallization temperature is 1000 ℃, the holding time is 2 hours, and the cooling method after the holding is completed is cooling with the furnace, and finally a niobate glass ceramic sample is obtained.

The XRD spectrum of the ceramic sample prepared in this embodiment is shown in the x=0.75 curve in Figure 1, the dielectric properties are shown in the x=0.75 curve in Figure 3, and the breakdown resistance is shown in the x=0.75 curve in Figure 4 According to the test, the glass-ceramic sample crystallized at 1000°C has a dielectric constant of 72 and a breakdown field strength of 820kV/cm at room temperature. According to calculation, its energy storage density reaches 2.14J/cm ³ .

Embodiment 5 (x=1)

Niobate glass ceramics with high energy storage density 6Na ₂ O-24SrO-30Nb ₂ O ₅ -40SiO ₂

(1) Using analytically pure SrCO ₃ , NaCO ₃ , Nb ₂ O ₅ , and SiO ₂ powders as raw materials, weigh the mass of each component according to the designed chemical composition 6Na ₂ O-24SrO-30Nb ₂ O ₅ -40SiO ₂ , the total mass of the sample is 80-100 grams.

(2) Select anhydrous ethanol as the dispersant, use agate balls to mill in a polytetrafluoroethylene ball mill tank at a speed of 50-60 rpm, and dry the evenly mixed slurry. The time of ball milling is 20~30h, and the ratio of ball to material during ball milling is (1.0~1.5):1.

(3) Put the dried glass raw material into the crucible for high-temperature melting, the heating rate of the high-temperature furnace is 1500° C., and the high-temperature melting time is 4 hours. Then the high-temperature melt is quickly poured into the preheated copper mold to obtain a transparent glass block without devitrification, and the glass block is placed in an annealing furnace for stress relief annealing. The preheating temperature of the copper mold is 500°C; then put the glass block into the annealing furnace to relieve stress, the stress relief holding temperature is 650°C; the holding time is 4h; after the holding is completed, the cooling method is furnace cooling.

(4) Use a slicer to cut the transparent glass block into thin slices with a thickness of 1.0mm; put the glass thin slices into an annealing furnace for controlled crystallization, the heating rate of the annealing furnace is 4°C/min, and the crystallization temperature is 1100 ℃, the holding time is 2 hours, and the cooling method after the holding is completed is cooling with the furnace, and finally a niobate glass ceramic sample is obtained.

The XRD spectrum of the ceramic sample prepared in this embodiment is shown in the x=1 curve in Figure 1, the dielectric properties are shown in the x=0.75 curve in Figure 3, and the breakdown resistance is shown in the x=1 curve in Figure 4 According to the test, the glass-ceramic sample crystallized at 1000°C has a dielectric constant of 65 and a breakdown field strength of 713kV/cm at room temperature. According to calculations, its energy storage density reaches 1.46J/cm ³ .

Table 1 shows the storage energy density of the products prepared in Examples 1-5 after crystallization at 1000°C

.

Claims (8)

1. A niobate-based glass-ceramic energy storage material, characterized in that the chemical composition of the energy storage material is [(Ba _{1- x} Sr _x ) ₂ NaNb ₅ O ₁₅ ] _0.6 -[SiO ₂ ] _0.4 , wherein 0≤x≤1, the energy storage material is prepared by the following method: (1) Use analytically pure BaCO ₃ , SrCO ₃ , NaCO ₃ , Nb ₂ O ₅ , and SiO ₂ powders as raw materials, and prepare materials according to the chemical composition formula of energy storage materials; (2) using absolute ethanol as a dispersant, adopting agate balls and placing the above-mentioned components in a ball mill jar for ball milling, and drying the uniformly mixed slurry; (3) Put the dried glass raw material into the crucible to melt at high temperature, then quickly pour the high-temperature melt into the preheated copper mold to obtain a transparent glass block without devitrification, and put the glass block into the retreat Stress-relief annealing in the furnace. During the high-temperature melting process, the heating rate of the glass furnace is 1-2°C/min, and the temperature is kept at 800°C for 3 hours. The high-temperature melting temperature is 1400-1600°C, and the high-temperature melting time is 2-5 hours; (4) Use a slicer to cut the transparent glass block into thin slices; put the glass flakes into an annealing furnace for controlled crystallization, the heating rate of the annealing furnace is 3-5°C/min, and the crystallization temperature is 800-1100°C , and the holding time is 1-3h, that is, the niobate-based glass-ceramic energy storage material is prepared. 2. A niobate-based glass-ceramic energy storage material according to claim 1, wherein the value of x is 0.25. 3. the preparation method of a kind of niobate-based glass-ceramic energy storage material as claimed in claim 1, is characterized in that, the method adopts the following steps: (1) Use analytically pure BaCO ₃ , SrCO ₃ , NaCO ₃ , Nb ₂ O ₅ , and SiO ₂ powders as raw materials, and prepare materials according to the chemical composition formula of energy storage materials; (2) using absolute ethanol as a dispersant, adopting agate balls and placing the above-mentioned components in a ball mill jar for ball milling, and drying the uniformly mixed slurry; (3) Put the dried glass raw material into the crucible to melt at high temperature, then quickly pour the high-temperature melt into the preheated copper mold to obtain a transparent glass block without devitrification, and put the glass block into the retreat Stress-relief annealing in the furnace. During the high-temperature melting process, the heating rate of the glass furnace is 1-2°C/min, and the temperature is kept at 800°C for 3 hours. The high-temperature melting temperature is 1400-1600°C, and the high-temperature melting time is 2-5 hours; (4) Use a slicer to cut the transparent glass block into thin slices; put the glass flakes into an annealing furnace for controlled crystallization, the heating rate of the annealing furnace is 3-5°C/min, and the crystallization temperature is 800-1100°C , and the holding time is 1-3h, that is, the niobate-based glass-ceramic energy storage material is prepared. 4 . The method for preparing a niobate-based glass-ceramic energy storage material according to claim 3 , wherein the time for ball milling and mixing the materials in step (2) is 10 to 20 hours. 5. The method for preparing a niobate-based glass-ceramic energy storage material according to claim 3, wherein the copper mold in step (3) is preheated to 500-650° C.; then the glass block Put it in an annealing furnace to relieve stress, and the stress-relief holding temperature is 500-650°C; the holding time is 3-5h, and it is cooled with the furnace after the holding is completed. 6. The method for preparing a niobate-based glass-ceramic energy storage material according to claim 3, wherein the copper mold in step (3) is preheated to 600°C in advance, and the stress relief temperature is 600°C . 7. The preparation method of a kind of niobate-based glass-ceramic energy storage material according to claim 3, characterized in that, when step (4) carries out controlled crystallization, the heating rate of the annealing furnace is 3-5°C/ min, the crystallization temperature is 800-1100°C, the holding time is 2-3h, and the furnace is cooled after the holding. 8. The application of a niobate-based glass-ceramic energy storage material as claimed in claim 1 as an energy storage capacitor material.