Lead-free high-voltage pulse-resistant energy-storage multilayer ceramic capacitor and manufacturing method thereof

Abstract

This invention relates to the field of ceramic capacitor technology, specifically to a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor and its preparation method. The method includes ball milling ceramic powder, solvent, dispersant, plasticizer, and silicone-based defoamer to obtain a slurry, which is then sequentially processed through casting, screen printing, lamination, pressing, cutting, glue removal, sintering, chamfering, end sealing, end firing, and electroplating to obtain the lead-free, high-voltage pulse energy storage multilayer ceramic capacitor; the film thickness is 25μm–40μm; 70Ag-30Pd, 60Ag-40Pd, or 90Ag-10Pd electrode slurry is used as the internal electrode material; after printing, it is dried at 65–75℃; the soft pressing temperature is 60℃–80℃; and the soft pressing temperature is... The pressure is 12MPa~15MPa, and the holding time is 15s~18s; the lamination pressure is 40MPa~55MPa, and the holding time is 10min~30min; the glue removal temperature is 265℃~325℃, and the holding time is 7h~11h; the sintering temperature is 1050℃~1200℃, and the sintering time is 2h~4h; in the electroplating process, the nickel plating current is 19A~21A, and the time is 90min~120min; the tin plating current is 13A~15A, and the time is 90min~120min.

Description

Technical Field

[0001] This invention relates to the field of ceramic capacitor technology, and in particular to a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor and its preparation method. Background Technology

[0002] With the rapid development of modern electronic technology towards high voltage, high frequency, and miniaturization, the performance requirements for pulsed power supplies are increasing. As a core energy storage component, pulsed multilayer ceramic capacitors (P-MLCCs) are experiencing a surge in demand in civilian and special fields such as new energy vehicles, space exploration, industrial accelerators, pulsed lasers, weapon ignition systems, and kinetic energy weapons. These applications require P-MLCCs to release enormous pulse energy in an extremely short time, thus imposing stringent requirements on their core performance indicators, including breakdown voltage, discharge current, and discharge rate.

[0003] Unlike traditional MLCCs that prioritize high capacitance, high-performance P-MLCCs (with lower equivalent series resistance, ESR) are designed to optimize energy storage and discharge capabilities. They require not only breakdown voltages of tens of thousands of volts to store sufficient energy but also the ability to release kiloampere-level currents in an extremely short time. In terms of materials, dielectrics suitable for manufacturing P-MLCCs are mainly divided into two categories: lead-containing antiferroelectrics (such as (Pb,La)(Zr,Sn,Ti)O3 systems) and lead-free ferroelectrics. Given increasingly stringent environmental regulations, traditional lead-based ceramics are being phased out globally due to their inherent toxicity, making lead-free relaxor ferroelectric materials an inevitable trend in current research and application. Among existing materials, BaTiO3(BT)-based and (Bi 0.5 Na 0.5 Mainstream lead-free energy storage systems, such as those based on TiO3(BNT), typically employ careful component design (e.g., introducing Bi(Zn)). 2 / 3 Nb 1 / 3 By inducing relaxation characteristics using substances such as O3 and SrTiO3, and utilizing the nano-polar microregions generated in the microstructure, the residual polarization intensity (Pr) can be effectively reduced and the polarization intensity difference (ΔP) can be increased, thus providing a theoretical basis for achieving higher discharge energy storage density (Wrec) and energy storage efficiency (η).

[0004] However, despite some progress in material modification, P-MLCCs still face significant technical bottlenecks in practical industrialization and high-end applications. Current products generally suffer from core issues such as insufficient discharge current capability, voltage withstand level failing to meet cutting-edge requirements, and low overall energy storage density, which severely restrict their promotion and application in next-generation high-power systems. Summary of the Invention

[0005] This invention provides a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor and its preparation method to solve the core problems of current products, such as insufficient discharge current capability, voltage withstand level failing to meet cutting-edge requirements, and low overall energy storage density.

[0006] This invention discloses a method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor, characterized by comprising: ball milling ceramic powder, solvent, dispersant, plasticizer, and silicone-based defoamer in a ball mill to obtain a slurry; and sequentially subjecting the slurry to casting, screen printing, stacking, lamination, cutting, glue removal, sintering, chamfering, end sealing, end firing, and electroplating processes to obtain the lead-free, high-voltage pulse energy storage multilayer ceramic capacitor.

[0007] The chemical formula of the ceramic powder is 0.95BaTiO3-0.05Bi[Zn]. 2 / 3 (Nb 0.9 Ta 0.1 ) 1 / 3 ]O3.

[0008] In the casting process, the film thickness is 25μm to 40μm, the film strip linear speed is 3000mm / min to 3500mm / min, and the temperatures of each zone are as follows: Zone I is 95℃ to 105℃, Zone II is 115℃ to 125℃, and Zone III is 135℃ to 145℃.

[0009] In the screen printing process, 70Ag-30Pd, 60Ag-40Pd or 90Ag-10Pd electrode pastes are used as internal electrode materials. The temperature of the drying oven is 65℃~70℃ in zone one, 65℃~70℃ in zone two, and 70℃~75℃ in zone three. The belt speed is 600mm / min~650mm / min.

[0010] In the lamination process, the soft pressure temperature is 60℃~80℃, the soft pressure is 12MPa~15MPa, and the holding time is 15s~18s.

[0011] In the lamination process, the lamination pressure is 40MPa to 55MPa, and the holding time is 10min to 30min.

[0012] In the glue removal process, the glue removal temperature is 265℃~325℃, and the temperature is maintained for 7h~11h.

[0013] In the sintering process, the sintering temperature is 1050℃~1200℃ and the sintering time is 2h~4h.

[0014] In the electroplating process, the nickel plating current is 19A~21A and the time is 90min~120min; the tin plating current is 13A~15A and the time is 90min~120min.

[0015] Optionally, zirconia plates or alumina plates are used as firing plates in the debinding and sintering processes.

[0016] Optionally, the mass ratio of the ceramic powder to the solvent is 2:1, the solvent is a mixture of toluene and anhydrous ethanol, the mass ratio of toluene to anhydrous ethanol is 4:1, the dispersant is trioleic acid glyceride, the plasticizer is dioctyl phthalate, and the silicone-based defoamer is dimethyl silicone oil.

[0017] Optionally, the preparation steps of the ceramic powder are as follows:

[0018] Step 1: Weigh BaCO3, TiO2, Nb2O5, Bi2O3, ZnO and Ta2O5 as raw materials according to the stoichiometric ratio of 1140:1140:9:30:40:1.

[0019] Step 2: Add zirconium balls to the nylon ball milling jar, pour the raw material into the ball milling jar, add anhydrous ethanol, and perform wet ball milling and mixing.

[0020] Step 3: After ball milling, place the raw material in a forced-air drying oven for drying to obtain raw material powder.

[0021] Step 4: Place the raw material powder in a muffle furnace for calcination, and allow it to cool naturally to room temperature to obtain the ceramic powder.

[0022] Optionally, in step two, the diameter of the zirconium ball is 5±0.2mm, the weight ratio of the zirconium ball to the raw material is (2~5):1, the weight ratio of the anhydrous ethanol to the raw material is (2~10):1, the ball milling speed is 300rpm~400rpm, and the ball milling time is 12h~24h.

[0023] Optionally, the drying temperature in step three is 80℃~150℃, and the drying time is 8h~12h.

[0024] Optionally, the calcination temperature in step four is 850℃~950℃, and the calcination time is 2h~4h.

[0025] The present invention also discloses a lead-free high-voltage pulse energy storage multilayer ceramic capacitor, which is prepared by the above-described method for preparing a lead-free high-voltage pulse energy storage multilayer ceramic capacitor.

[0026] Optionally, the lead-free high-voltage pulse energy storage multilayer ceramic capacitor has a capacitance of 615.6pF to 533nF and a loss tangent of (65~170)×10⁻⁶. -4 The breakdown voltage is 11.97kV~14.38kV, the discharge current is 125A~791A, the first peak discharge time is 26ns~1937ns, and the capacitor temperature coefficient (-55℃~125℃) is -13.66~-10.13%.

[0027] The beneficial effects of the lead-free, high-voltage pulse energy storage multilayer ceramic capacitor and its preparation method provided in this invention are as follows: the ceramic powder used in this method is 0.95BaTiO3-0.05Bi[Zn]. 2 / 3 (Nb 0.9 Ta 0.1 ) 1 / 3 Incorporating linear BiMO3 units into the ferroelectric ceramic matrix BaTiO3 effectively lowers the sintering temperature, inhibits excessive grain growth, reduces oxygen vacancy defects, and significantly improves material density and breakdown field strength. Appropriate amounts of bismuth-based compounds also help reduce dielectric losses and enhance the relaxation characteristics of BaTiO3-based ceramics, substantially reducing remanent polarization. Furthermore, the fabrication method optimizes the internal electrode, controls lamination pressure to achieve defect-free dense stacking, employs a specific multi-stage debinding curve to ensure stable and thorough removal of organic matter, and utilizes air sintering within a temperature range of 1050–1200°C to obtain a fine and uniform microstructure. Ultimately, this results in ceramic capacitors exhibiting high breakdown voltage, large discharge current, low loss, ultrafast discharge rate, and excellent temperature stability. Attached Figure Description

[0028] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0029] Figure 1 These are scanning electron microscope images of the ceramic powders from Examples 1 to 3 provided by this invention;

[0030] Figure 2 This is a charge-discharge curve of the 3838 specification product provided in Embodiment 1 of the present invention under different voltages. Detailed Implementation

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0032] This invention provides a method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor, comprising: ball milling ceramic powder, solvent, dispersant, plasticizer, and silicone-based defoamer in a ball mill to obtain a slurry; and sequentially subjecting the slurry to casting, screen printing, lamination, pressing, cutting, glue removal, sintering, chamfering, end sealing, end firing, and electroplating processes to obtain a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor.

[0033] The chemical formula of the ceramic powder is 0.95BaTiO3-0.05Bi[Zn]. 2 / 3 (Nb 0.9 Ta 0.1 ) 1 / 3 ]O3.

[0034] In the screen printing process, 70Ag-30Pd, 60Ag-40Pd, or 90Ag-10Pd internal electrode pastes are used as internal electrode materials.

[0035] In the casting process, the film thickness is 25μm to 40μm, the film strip linear speed is 3000mm / min to 3500mm / min, and the temperatures of each zone are as follows: Zone I is 95℃ to 105℃, Zone II is 115℃ to 125℃, and Zone III is 135℃ to 145℃.

[0036] In the screen printing process, the temperature of the drying oven is 65℃~70℃ in zone one, 65℃~70℃ in zone two, and 70℃~75℃ in zone three, with a belt speed of 600mm / min~650mm / min.

[0037] In the lamination process, the soft pressure temperature is 60℃~80℃, the soft pressure is 12MPa~15MPa, and the holding time is 15s~18s.

[0038] In the lamination process, the lamination pressure is 40MPa to 55MPa, and the holding time is 10min to 30min. In the adhesive removal process, the adhesive removal temperature is 265℃ to 325℃, and the holding time is 7h to 11h.

[0039] In the sintering process, the sintering temperature is 1050℃~1200℃ and the sintering time is 2h~4h.

[0040] In the electroplating process, the nickel plating current is 19A~21A and the time is 90min~120min; the tin plating current is 13A~15A and the time is 90min~120min.

[0041] Specifically, in the debinding and sintering processes, zirconia plates or alumina plates are used as the firing plates, which can be single-layer alumina plates, single-layer zirconia plates, or double-layer zirconia plates.

[0042] Specifically, the mass ratio of the ceramic powder to the solvent is 2:1, the solvent is a mixture of toluene and anhydrous ethanol, the mass ratio of toluene to anhydrous ethanol is 4:1, the dispersant is trioleic acid glyceride, the plasticizer is dioctyl phthalate, and the silicone-based defoamer is dimethyl silicone oil.

[0043] Specifically, the preparation steps of the ceramic powder are as follows:

[0044] Step 1: Weigh BaCO3, TiO2, Nb2O5, Bi2O3, ZnO and Ta2O5 as raw materials according to the stoichiometric ratio of 1140:1140:9:30:40:1.

[0045] Step 2: Add zirconium balls to the nylon ball milling jar, pour the raw material into the ball milling jar, add anhydrous ethanol, and perform wet ball milling and mixing.

[0046] Step 3: After ball milling, place the raw material in a forced-air drying oven for drying to obtain raw material powder.

[0047] Step 4: Place the raw material powder in a muffle furnace for calcination, and allow it to cool naturally to room temperature to obtain the ceramic powder.

[0048] Specifically, in step two, the diameter of the zirconium ball is 5±0.2mm; the weight ratio of the zirconium ball to the raw material is (2~5):1, the weight ratio of the anhydrous ethanol to the raw material is (2~10):1; the ball milling speed is 300rpm~400rpm, and the ball milling time is 12h~24h.

[0049] Specifically, the drying temperature in step three is 80℃~150℃, and the drying time is 8h~12h.

[0050] Specifically, the calcination temperature in step four is 850~950℃, and the calcination time is 2h~4h.

[0051] This invention also provides a lead-free high-voltage pulse energy storage multilayer ceramic capacitor, which is prepared using the above-described method for preparing a lead-free high-voltage pulse energy storage multilayer ceramic capacitor.

[0052] Specifically, the lead-free high-voltage pulse energy storage multilayer ceramic capacitor has a capacitance of 615.6pF to 533nF and a loss tangent of (65~170)×10⁻⁶. -4 The breakdown voltage is 11.97~14.38kV, the discharge current is 125~791A, the first peak discharge time is 26~1937ns, and the capacitor temperature coefficient (-55℃~125℃) is -13.66~-10.13%.

[0053] Example 1:

[0054] A method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor involves first preparing ceramic powder. BaCO3, TiO2, Nb2O5, Bi2O3, ZnO, and Ta2O5 are weighed as raw materials according to a stoichiometric ratio of 1140:1140:9:30:40:1. The raw materials are placed in a nylon ball mill jar, and zirconium balls with a diameter of 5 mm and anhydrous ethanol are added. The mass ratio of raw materials, anhydrous ethanol, and zirconium balls is controlled at 1:5:3. The mixture is then wet-milled at 350 rpm for 16 hours. The milled mixture is then placed in a forced-air drying oven and dried at 110°C for 10 hours to obtain raw material powder. The raw material powder is then placed in a muffle furnace and calcined at 900°C for 3 hours. After natural cooling to room temperature, the ceramic powder is obtained.

[0055] The ceramic powder was ball-milled with toluene, anhydrous ethanol, trioleic acid glyceride, and dioctyl phthalate in a ball mill, wherein the mass ratio of ceramic powder, toluene, and anhydrous ethanol was 10:4:1, to obtain a uniform slurry. Subsequently, a 35 μm thick film was formed using a casting process at a tape speed of 3300 mm / min. The film was dried sequentially in three temperature zones: 100°C, 120°C, and 140°C. A 70Ag-30Pd internal electrode slurry was then screen-printed onto the dried film. After printing, it was dried in three temperature zones: 68°C, 68°C, and 72°C, at a drying oven speed of 630 mm / min. Finally, alternating dielectric and electrode layers were stacked to form a structure. During the stacking process, the soft pressing temperature was 70°C, and the soft pressing pressure was 1... The pressure was applied at 3 MPa for 16 seconds, followed by isostatic pressing at 50 MPa for 20 minutes. The samples were then cut according to the electrode pattern to obtain green samples. The green samples were placed on an alumina sintering plate, first debinded at 300℃ for 9 hours, then sintered at 1100℃ for 3 hours, and then naturally cooled to room temperature before being removed. The samples underwent typical MLCC processes including chamfering, end sealing, and end sintering. In the electroplating process, nickel and tin plating were performed sequentially, with a nickel plating current of 20 A for 100 minutes and a tin plating current of 14 A for 100 minutes, resulting in P-MLCCs with dimensions of 2225 (5.59 mm × 6.35 mm), 3838 (9.65 mm × 9.65 mm), and 7680 (19.30 mm × 20.32 mm).

[0056] Example 2:

[0057] A method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor involves first preparing ceramic powder. BaCO3, TiO2, Nb2O5, Bi2O3, ZnO, and Ta2O5 are weighed as raw materials according to a stoichiometric ratio of 1140:1140:9:30:40:1. The raw materials are placed in a nylon ball mill jar, and zirconium balls with a diameter of 5 mm and anhydrous ethanol are added. The mass ratio of raw materials, anhydrous ethanol, and zirconium balls is controlled at 1:2:2. The mixture is then wet-milled at 300 rpm for 24 hours. The milled mixture is then placed in a forced-air drying oven and dried at 80°C for 8 hours to obtain raw material powder. The raw material powder is then placed in a muffle furnace and calcined at 850°C for 4 hours. After natural cooling to room temperature, the ceramic powder is obtained.

[0058] The ceramic powder was ball-milled with toluene, anhydrous ethanol, trioleic acid glyceride, and dioctyl phthalate in a ball mill, wherein the mass ratio of ceramic powder, toluene, and anhydrous ethanol was 10:4:1, to obtain a uniform slurry. Subsequently, a 25 μm thick film was formed using a casting process at a tape speed of 3000 mm / min. The film was then dried sequentially in three temperature zones: 95°C, 115°C, and 135°C. A 60Ag-40Pd internal electrode slurry was then screen-printed onto the dried film. After printing, the film was dried in three temperature zones: 65°C, 65°C, and 70°C, at a belt speed of 600 mm / min. Finally, alternating dielectric and electrode layers were stacked to form a structure. During the lamination process, the soft pressing temperature was 60℃, the soft pressing pressure was 12MPa, and the holding time was 18s. Then, it was subjected to isostatic pressing treatment with a holding pressure of 40MPa for 30min. Subsequently, it was cut according to the electrode pattern to obtain a green sample. The green sample was placed on a zirconia sintering plate, first debinding at 265℃ for 11h, then sintering at 1050℃ for 4h, and then naturally cooled to room temperature and removed. It went through typical MLCC processes of chamfering, end sealing, and end sintering in sequence. In the electroplating process, nickel plating and tin plating were performed in sequence. The nickel plating current was 19A and the time was 120min, and the tin plating current was 13A and the time was 120min, to obtain a P-MLCC with a size of 3838 (9.65mm×9.65mm).

[0059] Example 3:

[0060] A method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor involves first preparing ceramic powder. BaCO3, TiO2, Nb2O5, Bi2O3, ZnO, and Ta2O5 are weighed as raw materials according to a stoichiometric ratio of 1140:1140:9:30:40:1. The raw materials are placed in a nylon ball mill jar, and zirconium balls with a diameter of 5 mm and anhydrous ethanol are added. The mass ratio of raw materials, anhydrous ethanol, and zirconium balls is controlled at 1:5:10. The mixture is wet-milled at 400 rpm for 12 hours. The milled mixture is then placed in a forced-air drying oven and dried at 150°C for 8 hours to obtain raw material powder. The raw material powder is then placed in a muffle furnace and calcined at 950°C for 2 hours. After natural cooling to room temperature, the ceramic powder is obtained.

[0061] The ceramic powder was ball-milled with toluene, anhydrous ethanol, trioleic acid glyceride, and dioctyl phthalate in a ball mill, wherein the mass ratio of ceramic powder, toluene, and anhydrous ethanol was 10:4:1, to obtain a uniform slurry. Subsequently, a 40 μm thick film was formed using a casting process at a tape speed of 3500 mm / min. The film was then dried sequentially in three temperature zones: 105°C, 125°C, and 145°C. A 90Ag-10Pd internal electrode slurry was then screen-printed onto the dried film. After printing, the film was dried in three temperature zones: 70°C, 70°C, and 75°C, at a drying oven speed of 650 mm / min. Finally, an alternating dielectric and electrode layer structure was formed through lamination. During the lamination process, the soft pressing temperature was 80℃, the soft pressing pressure was 15MPa, and the holding time was 15s. Then, it was subjected to isostatic pressing treatment with a holding pressure of 55MPa for 10min. Subsequently, it was cut according to the electrode pattern to obtain a green sample. The green sample was placed on a double-layer zirconia sintering plate, first debinding at 325℃ for 7h, then sintering at 1200℃ for 2h, and then naturally cooled to room temperature and removed. It went through typical MLCC processes of chamfering, end sealing, and end sintering in sequence. In the electroplating process, nickel plating and tin plating were performed in sequence. The nickel plating current was 21A and the time was 90min, and the tin plating current was 15A and the time was 90min, to obtain a P-MLCC with a size of 3838 (9.65mm×9.65mm).

[0062] The samples prepared in Examples 1-3 were tested, and the following data were obtained, as shown in the table below:

[0063] Table 1

[0064]

[0065] Where: DF is the loss tangent; TCC is the capacitor temperature coefficient;

[0066] As shown in Table 1, using the dielectric system and fabrication process provided by this invention, P-MLCCs of various specifications ranging from 2225 to 7680 can be successfully fabricated, all exhibiting good overall performance. The capacitance, loss, withstand voltage, and pulse characteristics of capacitors of different sizes show a regular distribution related to their structural dimensions. Specifically, in Examples 1-2, the 3838 capacitor exhibits excellent balance in several key indicators: it has the highest breakdown voltage (14.38kV) and low and stable dielectric loss (65~79×10⁻⁶kV). -4 It exhibits excellent temperature stability (TCC between -10.13% and -11.99%) and a fast impulse response (first peak time 29 ns). For example... Figure 2 As shown, its discharge current increases linearly with the applied voltage, demonstrating good high-voltage linearity. Furthermore, the P-MLCC product provided by this invention can further enhance its overall withstand voltage level through a series structure, offering significant advantages in pulse power applications requiring high withstand voltage and rapid charge / discharge.

[0067] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Those skilled in the art can modify the technical solutions described in the above embodiments, or make equivalent substitutions for some of the technical features; and all such modifications and substitutions should fall within the protection scope of the appended claims of the present invention.

Claims

1. A method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor, characterized in that, include: Ceramic powder, solvent, dispersant, plasticizer, and silicone-based defoamer are ball-milled in a ball mill to obtain a slurry. The slurry is then subjected to casting, screen printing, lamination, pressing, cutting, debinding, sintering, chamfering, end sealing, end firing, and electroplating processes to obtain a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor. The chemical formula of the ceramic powder is 0.95BaTiO3-0.05Bi[Zn]. 2 / 3 (Nb 0.9 Ta 0.1 ) 1 / 3 O3; In the casting process, the film thickness is 25μm~40μm, the film strip linear speed is 3000mm / min~3500mm / min, and the temperatures of each temperature zone are as follows: temperature zone I is 95℃~105℃, temperature zone II is 115℃~125℃, and temperature zone III is 135℃~145℃. In the screen printing process, 70Ag-30Pd, 60Ag-40Pd or 90Ag-10Pd electrode pastes are used as internal electrode materials. The temperature of the drying oven is 65℃~70℃ in zone one, 65℃~70℃ in zone two, and 70℃~75℃ in zone three. The belt speed is 600mm / min~650mm / min. In the lamination process, the soft pressing temperature is 60℃~80℃, the soft pressing pressure is 12MPa~15MPa, and the holding time is 15s~18s. In the lamination process, the lamination pressure is 40MPa to 55MPa, and the holding time is 10min to 30min; In the glue removal process, the glue removal temperature is 265℃~325℃, and the heat preservation time is 7h~11h; In the sintering process, the sintering temperature is 1050℃~1200℃, and the sintering time is 2h~4h; In the electroplating process, the nickel plating current is 19A~21A and the time is 90min~120min; the tin plating current is 13A~15A and the time is 90min~120min.

2. The method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor according to claim 1, characterized in that, Zirconia plates or alumina plates are used as firing plates in the debinding and sintering processes.

3. The method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor according to claim 2, characterized in that, The mass ratio of the ceramic powder to the solvent is 2:1, the solvent is a mixture of toluene and anhydrous ethanol, the mass ratio of toluene to anhydrous ethanol is 4:1, the dispersant is trioleic acid glyceride, the plasticizer is dioctyl phthalate, and the silicone-based defoamer is dimethyl silicone oil.

4. The method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor according to claim 3, characterized in that, The preparation steps of the ceramic powder are as follows: Step 1: Weigh BaCO3, TiO2, Nb2O5, Bi2O3, ZnO and Ta2O5 as raw materials according to the stoichiometric ratio of 1140:1140:9:30:40:1; Step 2: Add zirconium balls to the nylon ball milling jar, pour the raw material into the ball milling jar, add anhydrous ethanol, and perform wet ball milling and mixing; Step 3: After ball milling, place the raw material in a forced-air drying oven for drying to obtain raw material powder; Step 4: Place the raw material powder in a muffle furnace for calcination, and allow it to cool naturally to room temperature to obtain the ceramic powder.

5. The method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor according to claim 4, characterized in that, In step two, the diameter of the zirconium ball is 5±0.2mm, the weight ratio of the zirconium ball to the raw material is (2~5):1, the weight ratio of the anhydrous ethanol to the raw material is (2~10):1, the ball milling speed is 300rpm~400rpm, and the ball milling time is 12h~24h.

6. The method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor according to claim 5, characterized in that, The drying temperature in step three is 80℃~150℃, and the drying time is 8h~12h.

7. The method for preparing a lead-free, high-voltage pulse energy storage multilayer ceramic capacitor according to claim 6, characterized in that, The calcination temperature in step four is 850℃~950℃, and the calcination time is 2h~4h.

8. A lead-free, high-voltage pulse energy storage multilayer ceramic capacitor, characterized in that, The lead-free, high-voltage pulse energy storage multilayer ceramic capacitor is prepared using the method described in any one of claims 1 to 7.

9. The lead-free, high-voltage pulse energy storage multilayer ceramic capacitor according to claim 8, characterized in that, The lead-free, high-voltage pulse energy storage multilayer ceramic capacitor has a capacitance of 615.6pF to 533nF and a loss tangent of (65° to 17°) × 10⁻⁶. -4 The breakdown voltage is 11.97~14.38kV, the discharge current is 125~791A, the first peak discharge time is 26~1937ns, and the capacitor temperature coefficient (-55℃~125℃) is -13.66~-10.13%.

Images