Potassium lithium tantalum niobate bismuthate energy storage ceramic, preparation method and application thereof

Abstract

The application discloses tantalum-niobium-bismuth potassium lithium energy storage ceramic and a preparation method and application thereof, and belongs to the energy storage ceramic field. 1‑x Li x )[(Ta 0.63 Nb 0.37 ) 1‑x Bi x ]O3, wherein 0 5+ (Bi 3+ )、Li + The application can improve the breakdown field strength, the saturation polarization strength and the small residual polarization strength by means of solid solution replacement and ion doping, so that the energy storage performance is improved.

Description

Technical Field

[0001] This invention relates to the field of energy storage ceramics, and more particularly to a potassium lithium tantalum niobate bismuthate energy storage ceramic, its preparation method, and its application. Background Technology

[0002] With the continuous growth of the global population, the demand for fossil energy resources is increasing, and the global environmental and climate crisis is becoming more severe. Energy shortage will be a major problem to be faced in the future. Therefore, energy storage will be an important part of future development. Currently, solid fuel cells are widely used in daily life due to their highest energy density, but their slow charge carrier migration speed makes them unsuitable for operation at high voltages (hundreds to thousands of volts). In contrast, dielectric ceramic capacitors have higher power density and faster charge and discharge rates, making them more promising. Currently, lead-based dielectric ceramic capacitors are still the mainstream in the market, but due to their environmental pollution and potential harm to human health, the development of lead-free dielectric ceramic capacitors is more important. Currently, research on lead-free dielectric ceramic capacitors mainly focuses on BaTiO3 (BT) and Na... 0.5 Bi 0.5 TiO3 (NBT), BiFeO3 (BF) and K 0.5 Na 0.5 Systems such as NbO3 (KNN) are used. However, these lead-free ceramic capacitors have low energy density and efficiency, limiting their widespread application in high-power energy storage devices. Therefore, researching and developing novel lead-free dielectric ceramic capacitors with high energy density and efficiency is of paramount importance.

[0003] Generally speaking, in order to achieve high energy storage density, materials need to possess high saturation polarization, high breakdown strength, and low remanent polarization. These characteristics work together to effectively improve the energy storage efficiency of materials.

[0004] Different matrices exhibit varying energy storage properties. Some matrices inherently possess these properties, while others exhibit piezoelectricity or ferroelectricity. These matrices often possess high polarization and high remanent polarization, making it difficult to convert them into energy storage materials through ordinary doping. Examples include KNN (potassium sodium niobate), PZT (lead zirconate titanate), and AgNbO3. Lead-containing matrices in these matrices are environmentally polluting, and while KNN shows potential as a replacement for PZT, achieving superior energy storage performance through proper control remains a significant challenge (currently, energy storage characteristics are often achieved by introducing numerous other elements, which is quite complex). Furthermore, some matrices may be difficult to control to achieve excellent energy storage performance.

[0005] Potassium tantalate niobate is a typical lead-free ferroelectric material. However, it has a large remanent polarization intensity and a low breakdown field strength at room temperature. Therefore, it has not shown good characteristics in energy storage. Summary of the Invention

[0006] Purpose of the invention

[0007] To overcome the above shortcomings, the present invention aims to provide a potassium lithium tantalum niobate bismuthate energy storage ceramic, its preparation method, and its application. The present invention involves adding Bi... 5+ (Bi 3+ ), Li + This invention achieves higher energy storage density and efficiency. Through solid solution substitution and ion doping, it can increase the breakdown field strength while simultaneously achieving a larger saturation polarization and a smaller remanent polarization, thereby improving its energy storage performance.

[0008] Solution

[0009] To achieve the objectives of this invention, the technical solution adopted is as follows:

[0010] In a first aspect, the present invention provides a potassium lithium tantalum niobate bismuthate energy storage ceramic, the general chemical formula of which is (K 1- x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x ]O3, where 0<x≤0.01.

[0011] Furthermore, 0.001≤x≤0.01 can be optionally 0.003≤x≤0.01, 0.003≤x≤0.009, 0.003≤x≤0.007, or 0.003≤x≤0.005.

[0012] Furthermore, it is obtained by adding bismuth and lithium to a potassium tantalate-niobate matrix.

[0013] Further, it includes the following steps: Press (K) 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x The molar ratio formula of O3 involves mixing K2CO3, Li2CO3, Nb2O5, Bi2O3 and Ta2O5 powders, ball milling for the first time, pre-firing, ball milling again, granulation, molding, debinding and sintering to obtain potassium lithium tantalum niobium bismuthate energy storage ceramic.

[0014] Furthermore, the initial ball milling and / or subsequent ball milling are both wet ball milling; optionally, a volatile solvent is used as the medium for ball milling, optionally anhydrous ethanol, optionally the ball milling time is 21 to 24 hours; optionally, zirconia balls are used during ball milling.

[0015] Furthermore, the pre-calcination temperature is 750–800℃, the pre-calcination time is optionally 6–10 h, and the atmosphere is optionally oxygenated or air-filled. Optionally, the material after the first ball milling is heated to the pre-calcination temperature at a rate of 1–5℃ / min, and the heating rate is optionally 2℃ / min.

[0016] Furthermore, granulation includes: adding a binder to the re-ball-milled material for granulation;

[0017] Optionally, the amount of adhesive added is 3-5 wt%, or optionally 4 wt%;

[0018] The adhesive may optionally be polyvinyl alcohol;

[0019] Optionally, before adding the binder, the material after ball milling is passed through an 80-120 mesh sieve, or optionally a 100 mesh sieve.

[0020] Further, the molding process includes: dry pressing the granulated particles obtained above at 100 MPa to obtain a preform.

[0021] Furthermore, the embryo is a circular piece with a diameter of 10 mm and a thickness of 1.4 mm.

[0022] Furthermore, the glue removal process includes heat preservation at 500-600℃, and optionally the glue removal heat preservation time is 80-120 minutes;

[0023] Optionally, during glue removal, the rate of heating to the holding temperature is 1–5℃ / min, optionally 2℃ / min.

[0024] Furthermore, sintering includes holding at 1170-1200℃.

[0025] The sintering and holding time can be 2-21h, 10-21h, 10-15h, or 12-15h.

[0026] Optionally, during sintering, the rate of heating to the holding temperature is 0.5–5 °C / min, or optionally 1–5 °C / min.

[0027] Thirdly, the application of the potassium lithium tantalum niobate bismuthate energy storage ceramic described in the first aspect or prepared by the preparation method described in the second aspect in the preparation of capacitors.

[0028] Beneficial effects

[0029] (1) The formulation of this invention does not contain the toxic element Pb, making it an environmentally friendly material. The potassium lithium tantalum niobate bismuthate lead-free energy storage ceramic of this invention has high energy storage density and energy storage efficiency.

[0030] (2) The preparation method of the lead-free energy storage ceramic material of potassium lithium tantalum niobate bismuthate of the present invention is simple, reproducible, and has good energy storage performance. For example, when the general formula is (K 0.995 Li 0.005 )[Ta 0.628 Nb 0.369 Bi 0.005 At O3, under an ambient temperature of 25℃ and a test frequency of 10Hz, when the applied electric field strength is 220kV / cm, its energy storage density W rec 1.75 J / cm 3 Its energy storage efficiency η is 83.6%, which is excellent among the various energy storage ceramics reported so far.

[0031] (3) In this invention, Bi and Li are doped into (K) 1-x )[(Ta 0.63 Nb 0.37 ) 1-x A novel energy storage ceramic is obtained from O3 matrix material. This invention greatly improves the breakdown field strength and energy storage density, and refines the hysteresis loop, thus significantly improving the energy storage efficiency of the ceramic.

[0032] (4) The sample composition of the present invention is simple, requiring only the doping of Bi and Li elements in the matrix elements. The preparation is simple, the pre-sintering temperature is low, which saves costs to a certain extent and speeds up the production cycle. The sintering temperature of the sample is below 1200℃, and the sample can achieve high energy storage efficiency and energy storage density under a low electric field of 220kv / cm. Energy storage ceramics with high energy storage density and efficiency under low electric field are safer in application, and the energy consumption is also lower. Attached Figure Description

[0033] One or more embodiments are illustrated by way of example with reference to the accompanying drawings, and these illustrative examples are not intended to limit the embodiments. The term "illustrative" as used herein means "serving as an example, embodiment, or illustration." Any embodiment illustrated herein as "illustrative" is not necessarily to be construed as superior to or better than other embodiments.

[0034] Figure 1 Hysteresis loop diagrams of the potassium lithium tantalum niobate bismuthate ceramic materials prepared in Examples 1 to 5 of Test Example 1 of the present invention.

[0035] Wherein, 0 represents Example 1, 0.003 represents Example 2, 0.005 represents Example 3, 0.007 represents Example 4, and 0.009 represents Example 5.

[0036] Figure 2 According to Test Example 1 of the present invention Figure 1 The calculated parameter values ​​(energy storage density and energy storage efficiency) are shown, where the horizontal axis represents the value of x, with 0 corresponding to Example 1, 0.003 to Example 2, 0.005 to Example 3, 0.007 to Example 4, and 0.009 to Example 5. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] Furthermore, to better illustrate the present invention, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that the present invention can be practiced without certain specific details. In some embodiments, materials, elements, methods, and means well known to those skilled in the art are not described in detail in order to highlight the spirit of the invention.

[0039] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0040] All raw materials used in this invention are commercially available.

[0041] This invention relates to a lead-free energy storage ceramic material of potassium lithium tantalum niobate, according to the formula (K 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x ]O3 (where 0 < x ≤ 0.01) Calculate and weigh the mass of each powder. The preparation method adopts solid-state sintering method, and the specific steps are as follows:

[0042] (1) Weigh dry, high-purity powder raw materials according to the formula. Their chemical formulas and purities are: K2CO3 (99.0%), Li2CO3 (98.0%), Nb2O5 (99.5%), Bi2O3 (99.0%) and Ta2O5 (99.5%).

[0043] (2) The powdered raw materials, zirconia balls, and anhydrous ethanol milling media weighed in step 1 are placed together in a nylon can and ball-milled for 21-24 hours. Subsequently, the uniformly mixed powder is pre-calcined in a muffle furnace. The heating and cooling rates of the muffle furnace are both 2℃ / min, the pre-calcination temperature is 750-800℃, and the holding time is 6-10 hours, to obtain (K... 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x Powder synthesized after pre-calcination of O3.

[0044] (3) The powder obtained in step 2 is subjected to secondary ball milling with anhydrous ethanol and zirconium oxide balls as media for 21-24 hours.

[0045] (4) After drying the powder obtained in step 3, pass it through a 100-mesh sieve, and add polyvinyl alcohol solution at 3-5 wt% of the powder mass to granulate it. The concentration of polyvinyl alcohol solution is 4 wt%.

[0046] (5) The granulated powder from step 4 is dry-pressed under a pressure of 100 MPa to obtain a round blank with a diameter of 10 mm and a thickness of 1.4 mm.

[0047] (6) The preform obtained in step 5 is kept at 500-600℃ for 80-120 min to remove the glue, with a heating rate of 2℃ / min.

[0048] (7) The preform obtained in step 6 after debinding is heated at a rate of 2℃ / min and kept at 1170-1200℃ for 2-21h. After sintering is completed, it is cooled to room temperature in the furnace and taken out.

[0049] (8) Grind the sintered energy storage ceramic material sample obtained in step 7 to a thickness of 0.2-0.4 mm, then clean it with ultrasonic and dry it. Coat the silver electrodes on both sides and test the energy storage performance.

[0050] The hysteresis loops involved in this invention were all measured by a TF ANALYZER 2000HS ferroelectric comprehensive analyzer (aixACCTSystems GmbH, Germany), and the energy storage density and energy storage efficiency data were all calculated from the corresponding hysteresis loops.

[0051] Example 1

[0052] According to the general formula (K) 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x [O3], where x = 0, the molar ratio was calculated and dry, high-purity powder raw material was weighed; the weighed powder raw material was loaded into a nylon can with zirconia balls and anhydrous ethanol as the ball milling media, and ball milled for 24 h. Subsequently, the uniformly mixed powder was pre-calcined in a muffle furnace. The heating and cooling rate of the muffle furnace was 2℃ / min, the pre-calcination temperature was 750℃, and the holding time was 10 h, yielding K[Ta] 0.628 Nb 0.369 O3 basic ceramic powder was ball-milled again for 24 hours after pre-firing. The powder after the second ball milling was dried and passed through a 100-mesh sieve. 4% PVA (polyvinyl alcohol) was added to the sieved powder for granulation. The resulting granules were dry-pressed under 100 MPa pressure to obtain round blanks with a diameter of 10 mm and a thickness of 1.4 mm. The formed blanks were heated to 600℃ and held for 2 hours to remove the binder, then heated to 1178℃ and held for 12 hours. After cooling to room temperature in the furnace, sintering was completed, yielding K[Ta]. 0.628 Nb 0.369 O3 energy storage ceramics.

[0053] Example 2

[0054] According to the general formula (K) 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x O 3， The molar ratio of x = 0.003 was calculated, and dry, high-purity powder raw materials were weighed. The weighed powder raw materials were then placed in a nylon jar using zirconia balls and anhydrous ethanol as milling media, and milled in a ball mill for 24 hours. Subsequently, the uniformly mixed powder was pre-calcined in a muffle furnace. The heating and cooling rate of the muffle furnace was 2℃ / min, the pre-calcination temperature was 750℃, and the holding time was 10 hours, yielding (K... 0.997 Li 0.003 )[Ta 0.628 Nb 0.369 Bi 0.003O3 basic ceramic powder was ball-milled again for 24 hours after pre-firing. The powder after the second ball milling was dried and passed through a 100-mesh sieve. 4% PVA (polyvinyl alcohol) was added to the sieved powder for granulation. The resulting granules were dry-pressed under 100 MPa pressure to obtain round blanks with a diameter of 10 mm and a thickness of 1.4 mm. The formed blanks were heated to 600℃ and held for 2 hours to remove the binder, then heated to 1178℃ and held for 12 hours. After cooling to room temperature in the furnace, sintering was completed, yielding (K) 0.997 Li 0.003 )[Ta 0.628 Nb 0.369 Bi 0.003 O3 energy storage ceramics.

[0055] Example 3

[0056] According to the general formula (K) 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x O 3， The molar ratio of x = 0.005 was calculated, and dry, high-purity powder raw materials were weighed. The weighed powder raw materials were then placed in a nylon jar using zirconia balls and anhydrous ethanol as milling media, and milled in a ball mill for 24 hours. Subsequently, the uniformly mixed powder was pre-calcined in a muffle furnace. The heating and cooling rate of the muffle furnace was 2℃ / min, the pre-calcination temperature was 750℃, and the holding time was 10 hours, yielding (K... 0.995 Li 0.005 )[Ta 0.628 Nb 0.369 Bi 0.005 O3 basic ceramic powder was ball-milled again for 24 hours after pre-firing. The powder after the second ball milling was dried and passed through a 100-mesh sieve. 4% PVA (polyvinyl alcohol) was added to the sieved powder for granulation. The resulting granules were dry-pressed under 100 MPa pressure to obtain round blanks with a diameter of 10 mm and a thickness of 1.4 mm. The formed blanks were heated to 600℃ and held for 2 hours to remove the binder, then heated to 1178℃ and held for 12 hours. After cooling to room temperature in the furnace, sintering was completed, yielding (K) 0.995 Li 0.005 )[Ta 0.628 Nb 0.369 Bi 0.005 O3 energy storage ceramics.

[0057] Example 4

[0058] According to the general formula (K) 1-x Li x )[(Ta 0.63 Nb0.37 ) 1-x Bi x O 3， The molar ratio of x = 0.007 was calculated, and dry, high-purity powder raw materials were weighed. The weighed powder raw materials were then placed in a nylon jar using zirconia balls and anhydrous ethanol as milling media, and milled in a ball mill for 24 hours. Subsequently, the uniformly mixed powder was pre-calcined in a muffle furnace. The heating and cooling rate of the muffle furnace was 2℃ / min, the pre-calcination temperature was 750℃, and the holding time was 10 hours, yielding (K... 0.993 Li 0.007 )[Ta 0.628 Nb 0.369 Bi 0.007 O3 basic ceramic powder was ball-milled again for 24 hours after pre-firing. The powder after the second ball milling was dried and passed through a 100-mesh sieve. 4% PVA (polyvinyl alcohol) was added to the sieved powder for granulation. The resulting granules were dry-pressed under 100 MPa pressure to obtain round blanks with a diameter of 10 mm and a thickness of 1.4 mm. The formed blanks were heated to 600℃ and held for 2 hours to remove the binder, then heated to 1178℃ and held for 12 hours. After cooling to room temperature in the furnace, sintering was completed, yielding (K) 0.993 Li 0.007 )[Ta 0.628 Nb 0.369 Bi 0.007 O3 energy storage ceramics.

[0059] Example 5

[0060] According to the general formula (K) 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x O 3， The molar ratio of x = 0.009 was calculated, and dry, high-purity powder raw materials were weighed. The weighed powder raw materials were then placed in a nylon jar using zirconia balls and anhydrous ethanol as milling media, and milled in a ball mill for 24 hours. Subsequently, the uniformly mixed powder was pre-calcined in a muffle furnace. The heating and cooling rate of the muffle furnace was 2℃ / min, the pre-calcination temperature was 750℃, and the holding time was 10 hours, yielding (K... 0.991 Li 0.009 )[Ta 0.628 Nb 0.369 Bi 0.009O3 basic ceramic powder was ball-milled again for 24 hours after pre-firing. The powder after the second ball milling was dried and passed through a 100-mesh sieve. 4% PVA (polyvinyl alcohol) was added to the sieved powder for granulation. The resulting granules were dry-pressed under 100 MPa pressure to obtain round blanks with a diameter of 10 mm and a thickness of 1.4 mm. The formed blanks were heated to 600℃ and held for 2 hours to remove the binder, then heated to 1178℃ and held for 12 hours. After cooling to room temperature in the furnace, sintering was completed, yielding (K) 0.991 Li 0.009 )[Ta 0.628 Nb 0.369 Bi 0.009 O3 energy storage ceramics.

[0061] Test Example 1

[0062] The ceramic preforms prepared in Examples 1-5 were polished to a thickness of 0.1 mm using 400-mesh diamond abrasive. After ultrasonic cleaning and drying, high-temperature conductive silver paste was coated on both sides, and the preforms were fired at 600°C for 30 minutes in a muffle furnace. After natural cooling to room temperature, the samples were analyzed using the TF ANALYZER ferroelectric analysis system.

[0063] The polarization intensity of the ceramic material as a function of electric field was measured by 2000HS (aixACCT Systems GmbH, Germany) at an ambient temperature of 25°C and a test frequency of 10Hz. The results are shown in [Figure number missing]. Figure 1 The detection and system calculation results of energy storage density and energy storage efficiency are as follows: Figure 2 .

[0064] Figure 1 The results show that as the doping amounts of Bi and Li increase, the hysteresis loop gradually becomes thinner and the residual polarization intensity decreases significantly.

[0065] Figure 2 The results show that, compared to Example 1 (x = 0), the breakdown field strength E is higher after incorporating Bi and Li elements. b The energy storage efficiency of the ceramic material is significantly increased due to the improved hysteresis loop and refined hysteresis loop. Table 1 shows the energy storage density and efficiency of the energy storage materials in Examples 1-5. When x = 0 (Example 1), at an ambient temperature of 25°C and a test frequency of 10Hz, the energy storage density and efficiency of the material are significantly improved. Figure 1 When the energy storage density W is reached, rec =0.55J / cm 3The energy storage efficiency η = 34.8%, and the maximum electric field can only be applied up to 130 kV / cm (breakdown strength). When x = 0.005 (Example 3), at an ambient temperature of 25°C and a test frequency of 10 Hz, the energy storage density W is [value missing]. rec =1.75J / cm 3 The energy storage efficiency η = 83.6%.

[0066] The performance of the energy storage materials prepared in Examples 1-5 is shown in Table 1.

[0067] Table 1. Performance of energy storage materials in Examples 1-5

[0068]

[0069] As shown in Table 1, the polarization intensity of the ceramic material decreased slightly after the addition of Bi and Li elements, the residual polarization intensity decreased significantly, and the breakdown field strength increased significantly, thus achieving high energy storage density and high energy storage efficiency.

[0070] Generally speaking, energy storage density and efficiency gradually increase with the application of an electric field. However, Example 3 can achieve high energy storage performance under a low electric field of 220 kV / cm, indicating that the energy storage ceramic prepared by this invention will be safer in application and will have lower energy consumption.

[0071] The preparation method of the potassium lithium tantalum niobate bismuthate lead-free energy storage ceramic material of the present invention is simple, reproducible, and has good energy storage performance. For example, when the general formula is (K 0.995 Li 0.005 )[Ta 0.628 Nb 0.369 Bi 0.005 When O3 (Example 3) is tested at an ambient temperature of 25°C and a test frequency of 10Hz, its energy storage density W is [missing value]. rec 1.75 J / cm 3 With an energy storage efficiency η of 83.6%, it boasts excellent energy storage efficiency, safer application, and lower energy consumption.

[0072] Through continuous experimentation and improvement, the inventors have been able to transform the KTN matrix into a novel lead-free energy storage material, potentially expanding the research scope of energy storage materials. Furthermore, improving its energy storage performance requires only two elemental doping methods, making it simple and efficient. Currently, no one has reported on or even studied the energy storage performance of potassium tantalate-niobate matrix; this invention opens up a new direction for energy storage materials.

[0073] In summary, this invention discovers a novel energy storage ceramic (K... 1-x )[(Ta 0.63 Nb 0.37 )1-x [O3, This invention incorporates Bi and Li elements into (K) 1-x )[(Ta 0.63 Nb 0.37 ) 1-x The O3 matrix material greatly improves the breakdown field strength and energy storage density, and refines the hysteresis loop, thus significantly improving the energy storage efficiency of the ceramic.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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 of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A potassium lithium tantalum niobate bismuthate energy storage ceramic, characterized in that, Its general chemical formula is (K 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x ]O3, where 0 < x ≤ 0.

01.

2. The energy storage ceramic of potassium lithium tantalum niobate bismuthate according to claim 1, characterized in that, Where 0.001≤ x ≤ 0.

01.

3. The energy storage ceramic of potassium lithium tantalum niobate bismuthate according to claim 1, characterized in that, Where 0.003≤ x ≤ 0.

01.

4. The energy storage ceramic of potassium lithium tantalum niobate bismuthate according to claim 1, characterized in that, Where 0.003≤ x ≤0.

009.

5. The energy storage ceramic of potassium lithium tantalum niobate bismuthate according to claim 1, characterized in that, Where 0.003≤ x ≤0.

007.

6. The energy storage ceramic of potassium lithium tantalum niobate bismuthate according to claim 1, characterized in that, Where 0.003≤ x ≤0.

005.

7. The energy storage ceramic of potassium lithium tantalate niobate according to any one of claims 1 to 6, characterized in that, It is obtained by adding bismuth and lithium to a potassium tantalate-niobate matrix.

8. A method for preparing a potassium lithium tantalum niobate bismuthate energy storage ceramic according to any one of claims 1 to 7, characterized in that, Includes the following steps: Press (K) 1-x Li x )[(Ta 0.63 Nb 0.37 ) 1-x Bi x The molar ratio formula of O3 involves mixing K2CO3, Li2CO3, Nb2O5, Bi2O3 and Ta2O5 powders, ball milling for the first time, pre-firing, ball milling again, granulation, molding, debinding and sintering to obtain potassium lithium tantalum niobium bismuthate energy storage ceramic.

9. The preparation method according to claim 8, characterized in that, Both the initial ball milling and / or the subsequent ball milling are wet ball milling processes.

10. The preparation method according to claim 9, characterized in that, Ball milling was performed using a volatile solvent as the medium.

11. The preparation method according to claim 10, characterized in that, The volatile solvent is anhydrous ethanol.

12. The preparation method according to claim 10, characterized in that, The ball milling time is 21~24h.

13. The preparation method according to claim 10, characterized in that, Zirconia balls are used during ball milling.

14. The preparation method according to any one of claims 8 to 13, characterized in that, The preheating temperature is 750~800℃.

15. The preparation method according to claim 14, characterized in that, Preheating time is 6-10 hours.

16. The preparation method according to claim 14, characterized in that, Pre-firing uses an oxygen-rich atmosphere.

17. The preparation method according to claim 14, characterized in that, Pre-firing is performed using an air atmosphere.

18. The preparation method according to claim 14, characterized in that, The material after the first ball milling is heated to the pre-calcination temperature at a rate of 1~5℃ / min.

19. The preparation method according to claim 18, characterized in that, The heating rate is 2℃ / min.

20. The preparation method according to any one of claims 8 to 13, characterized in that, Granulation includes: A binder is added to the material after ball milling for granulation.

21. The preparation method according to claim 20, characterized in that, The amount of adhesive added is 3-5 wt%.

22. The preparation method according to claim 20, characterized in that, The amount of adhesive added is 4 wt%.

23. The preparation method according to claim 20, characterized in that, The adhesive is polyvinyl alcohol.

24. The preparation method according to claim 20, characterized in that, Before adding the binder, the material that has been ball-milled again should be sieved through an 80-120 mesh sieve.

25. The preparation method according to claim 20, characterized in that, Before adding the binder, the material that has been ball-milled again is sieved through a 100-mesh sieve.

26. The preparation method according to any one of claims 8 to 13, characterized in that, Molding includes: The granules obtained by granulation are dry-pressed at 100 MPa to obtain embryos.

27. The preparation method according to claim 26, characterized in that, The embryo is a circular piece with a diameter of 10 mm and a thickness of 1.4 mm.

28. The preparation method according to any one of claims 8 to 13, characterized in that, The adhesive removal process includes heat preservation at 500-600℃.

29. The preparation method according to claim 28, characterized in that, The adhesive removal and heat preservation time is 80-120 minutes.

30. The preparation method according to claim 28, characterized in that, During glue removal, the rate of heating to the holding temperature is 1~5℃ / min.

31. The preparation method according to claim 28, characterized in that, During glue removal, the rate of heating to the holding temperature is 2℃ / min.

32. The preparation method according to any one of claims 8 to 13, characterized in that, Sintering includes holding at 1170-1200℃.

33. The preparation method according to claim 32, characterized in that, The sintering holding time is 2-21 hours.

34. The preparation method according to claim 32, characterized in that, The sintering holding time is 10~21h.

35. The preparation method according to claim 32, characterized in that, The sintering holding time is 10~15h.

36. The preparation method according to claim 32, characterized in that, The sintering holding time is 12-15 hours.

37. The preparation method according to claim 32, characterized in that, During sintering, the rate of heating to the holding temperature is 0.5~5℃ / min.

38. The preparation method according to claim 32, characterized in that, During sintering, the rate of heating to the holding temperature is 1~5℃ / min.

39. The application of a lithium potassium bismuth tantalum niobate energy storage ceramic according to any one of claims 1 to 7 or a lithium potassium bismuth tantalum niobate energy storage ceramic prepared by any one of claims 8 to 38 in the preparation of a capacitor.

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