CN112563040A - Ceramic double electric layer capacitor and preparation method thereof - Google Patents

Abstract

The invention discloses a ceramic double electric layer capacitor and a preparation method thereof, wherein the ceramic double electric layer capacitor comprises at least two conductor layers and at least one electrolyte layer, and one electrolyte layer is arranged between every two adjacent conductor layers; each conductor layer is made of semiconductor conductive ceramics; each electrolyte layer is an inorganic solid electrolyte ceramic. The invention has the advantages of large withstand voltage, low dielectric loss, high capacitance and good safety. The solid electrolyte and the semiconductor ceramic are combined, various novel energy storage devices can be designed, effective control of an interface between the solid electrolyte and the semiconductor ceramic is realized, and the solid electrolyte and the semiconductor ceramic are suitable for the technical fields of large-capacity energy storage technology and high-voltage-withstanding capacitor.

Description

Ceramic double electric layer capacitor and preparation method thereof

Technical Field

The invention belongs to the technical field of ceramic capacitors, particularly relates to a ceramic material, and particularly relates to a ceramic double-electric-layer capacitor and a preparation method thereof.

Background

With the rapid development of global economy, the demand of people for energy is greatly increased. Due to the non-renewable nature of fossil energy and the low energy conversion and utilization rate of the traditional process, the development of efficient, clean and safe energy conversion and storage technology has become a hot point of research and development in various countries, and among them, a capacitor with high power density and excellent cycle performance is always a core device, and how to improve the energy density and the safety of the capacitor is a key problem. Meanwhile, the capacitor with excellent performance can also be used in the fields of military affairs, electric power, electronics, aerospace, transportation and the like, and has important military value and wide market application prospect.

Lithium hexafluorophosphate (LiPF) is often used in an electric double layer capacitor of a supercapacitor which is currently used₆) A liquid electrolyte material mixed with an organic solvent such as lithium oxalyldifluoroborate (LiDFBO) achieves a large specific capacity by concentrating ions in the electrolyte on a current collector such as Cu or graphite. However, such liquid electrolytesThe electrolyte of the system capacitor is easy to leak, the withstand voltage is low, and the capacitor adopting the system needs complex packaging technology and equipment and is not high in temperature resistance. Therefore, a lithium ion electric double layer capacitor requires a solid electrolyte with higher withstand voltage, otherwise high requirements of the practical energy storage device in terms of capacity and safety cannot be satisfied.

For the above reasons, there is an urgent need to develop a high-voltage-withstanding, high-specific-capacity, safe and high-performance electric double layer capacitor.

Disclosure of Invention

The present invention aims to provide a ceramic double electric layer capacitor and a preparation method thereof, so as to overcome the defects of the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

a ceramic double electric layer capacitor comprises at least two conductor layers and at least one electrolyte layer, wherein one electrolyte layer is arranged between every two adjacent conductor layers; each conductor layer is made of semiconductor conductive ceramics; each electrolyte layer is an inorganic solid electrolyte ceramic.

In a further improvement of the invention, the inorganic solid electrolyte ceramic is Li_3xLa_2/3-xTiO₃A polycrystalline structure ceramic, wherein x is 0.02 to 0.167; or the inorganic solid electrolyte ceramic is Li_7-xLa₃Zr_2-xNb_xO₁₂A polycrystalline structure ceramic, wherein x is 0 to 0.2; the conductor layer is made of CaMnO₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃One or more of a semiconducting ceramic; wherein x is 0.001-0.10.

In a further development of the invention, the Li_3xLa_2/3-xTiO₃The polycrystalline structure ceramic is ABO₃One or more of a cubic phase structure of perovskite, a hexagonal phase structure of perovskite, a tetragonal phase structure of perovskite and an orthogonal phase structure of perovskite; the Li_7-xLa₃Zr_2-xNb_xO₁₂The polycrystalline structure ceramic is garnet-type cubic phase structure and garnet-type tetragonal phase structureOne or more of; the solid electrolyte ceramic is Li_3xLa_2/3-xTiO₃The ceramic has a polycrystalline structure, wherein x is 0.10 to 0.17.

A method for preparing a ceramic double electric layer capacitor comprises the following steps:

step 1: mixing Li₂O-SiO₂-B₂O₃Glass powder and Li₂O-SiO₂-P₂O₅One of glass powder and perovskite type Li_3xLa_2/3-xTiO₃Mixing the solid electrolyte pre-sintering powder to obtain solid electrolyte powder; wherein x is 0.02-0.167;

or mixing Li₂O-SiO₂-B₂O₃Glass powder and Li₂O-SiO₂-P₂O₅One of the glass powders and garnet type Li_{7- x}La₃Zr_2-xNb_xO₁₂Mixing the solid electrolyte pre-sintering powder to obtain solid electrolyte powder; wherein x is 0-0.5;

step 2: preparing solid electrolyte powder into solid electrolyte slurry, and processing and forming the solid electrolyte slurry into an electrolyte ceramic membrane;

adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Preparing one or more of the semiconductor ceramics into electronic conductor slurry, and processing and molding the electronic conductor slurry into an electronic conductor ceramic membrane; wherein x is 0.001-0.10;

and step 3: and cutting the electronic conductor ceramic membrane and the electrolyte ceramic membrane, sequentially laminating the electronic conductor, the ionic conductor and the electronic conductor in sequence, and finally sintering to obtain the ceramic double-electric-layer capacitor.

A further development of the invention is that in step 1, the perovskite Li_3xLa_2/3-xTiO₃In cubic, hexagonal, tetragonal or orthorhombic phase structure, garnet-type Li_7-xLa₃Zr_2-xNb_xO₁₂Is in a cubic phase or tetragonal phase structure;

perovskite type Li_3xLa_2/3-xTiO₃The solid electrolyte pre-sintering powder is prepared by the following processes: mixing lithium carbonate, lanthanum oxide and titanium dioxide according to Li_3xLa_2/3-xTiO₃Mixing, ball-milling and drying the mixture according to the stoichiometric ratio, then heating the mixture to 900-1100 ℃ in air atmosphere, and keeping the temperature for 1-5 hours to prepare solid electrolyte ceramic pre-sintering powder;

garnet type Li_7-xLa₃Zr_2-xNb_xO₁₂The solid electrolyte pre-sintering powder is prepared by the following processes: lithium carbonate, lanthanum oxide, zirconium oxide, titanium dioxide and niobium pentoxide are mixed according to garnet type Li_7-xLa₃Zr_2-xNb_xO₁₂Mixing the raw materials according to the stoichiometric ratio, ball-milling, drying, heating to 900-1100 ℃ in an air atmosphere, and keeping the temperature for 1-5 hours to obtain solid electrolyte ceramic pre-sintering powder; wherein x is 0 to 0.17.

A further development of the invention consists in the preparation of perovskite Li_3xLa_2/3-xTiO₃Solid electrolyte pre-sintered powder and garnet-type Li_7-xLa₃Zr_2-xNb_xO₁₂The heating rate of the solid electrolyte pre-sintering powder is 0.5-5 ℃/min.

A further development of the invention is that, in step 1, Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅The glass powder is prepared by the following steps:

several of lithium carbonate, boron oxide, silicon dioxide and lithium phosphate are according to Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅Mixing the above stoichiometric ratio, keeping the temperature at 1000-1200 ℃ for not more than 6 hours, quenching to form solid glass, and grinding to obtain Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅And (3) glass powder.

The invention has the further improvement that the temperature is increased to 1000-1200 ℃ from room temperature at the temperature increase rate of 2-5 ℃/min; deionizationQuenching in water; li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅The glass powder is 60-120 meshes.

In a further development of the invention, in step 2, the CaMnO₃Is prepared by the following steps: mixing calcium carbonate and manganese dioxide, ball-milling, drying, heating to 900-1100 ℃ in air atmosphere, and keeping the temperature for 1-5 hours to obtain CaMnO₃；

SrTi_1-xNb_xO₃The semiconductor ceramic is prepared by the following processes: mixing strontium carbonate, niobium pentoxide and titanium dioxide according to SrTi_1-xNb_xO₃The SrTi is obtained by metering, mixing, ball milling and drying, then heating to 900-1100 ℃ in air atmosphere, and keeping the temperature for 1-5 hours_1-xNb_xO₃A semiconductor ceramic; wherein x is 0.001-0.10.

In a further development of the invention, the solid electrolyte ceramic membrane is produced by the following process: grinding and sieving solid electrolyte powder, and then adding an adhesive, a solvent and a plasticizer to obtain solid electrolyte slurry; adding the solid electrolyte slurry into a casting machine, coating the solid electrolyte slurry on a PET plastic belt to form a slurry layer, and drying to obtain a solid electrolyte ceramic membrane;

the electronic conductor ceramic membrane is prepared by the following processes: adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Grinding one or more of the semiconductor ceramics, sieving, and adding an adhesive, a solvent and a plasticizer to obtain electronic conductor slurry; adding the electronic conductor slurry into a casting machine, coating the electronic conductor slurry on a PET plastic belt to form a slurry layer, and drying to obtain an electronic conductor ceramic membrane;

in the preparation process of the solid electrolyte ceramic membrane and the electronic conductor ceramic membrane, the thickness of a slurry layer is 20-500 micrometers, the tape-moving speed of a steel tape of a casting machine is 5-30 mm/s, the thickness of the solid electrolyte ceramic membrane and the thickness of the electronic conductor ceramic membrane are 20-300 micrometers, and the width of the solid electrolyte ceramic membrane and the width of the electronic conductor ceramic membrane are 100 millimeters;

the specific conditions of sintering are as follows: the sintering temperature is 900-1500 ℃, and the sintering time is 0.5-36 hours.

The invention is further improved in that the adhesive is polyethylene glycol butyral, the solvent is one or more of ethanol, methanol and propanol, glycol and glycerol, and the plasticizer is one or more of dibutyl phthalate and dioctyl phthalate.

Compared with the prior art, the invention has the following beneficial effects:

the all-solid-state double electric layer capacitor is characterized in that an electrolyte layer is arranged between two adjacent conductor layers, the capacitor with the double electric layer structure, which is simple in structure and easy to process and manufacture, is effectively constructed by using the interface characteristics of electronic conductor ceramics as electrode layers and solid electrolytes, and the safety problems that the traditional double electric layer capacitor cannot resist high temperature, is easy to burn and the like are avoided because the electrode layers and the solid electrolyte layers are made of solid ceramics. In addition, when an electric field is applied to the capacitor, a large amount of electron enrichment is formed near the interface of the electrolyte and the electron conductor layer, and the electrons cannot pass through the electrolyte layer to form a large built-in electric field, so that ions of the electrolyte are pushed to rapidly move, a very large polarization process is generated, and a large capacitor is obtained. In addition, because the structure utilizes conductive ceramics as an electronic conductor layer to replace the traditional electrode material, the MLCC without metal internal electrodes in series connection can be more easily completed, so that the withstand voltage of the MLCC is greatly increased, and compared with the traditional capacitor at present, the capacity of the MLCC is larger due to higher withstand voltage and dielectric constant. Therefore, the all-solid-state electric double layer capacitor will become a next-generation safer large-capacity capacitor.

Furthermore, the invention introduces the semiconductor Ceramic as the electronic conductor layer to replace the traditional electrode to form different Ceramic composite electric double layer capacitor structures of the electronic conductor layer-solid electrolyte layer-electronic conductor layer without the metal inner electrode, generates a large amount of charge accumulation between the electronic conductor layer and the solid electrolyte layer to form energy storage, forms a series lamination by utilizing the preparation process of a Multi-layer Ceramic capacitor (MLCC) to improve the voltage resistance, and effectively constructs a Ceramic electric double layer capacitor structure without the metal inner electrode, which has simple structure and is easy to process and manufacture.

Drawings

FIG. 1 is a schematic view showing the structure of a solid electric double layer capacitor according to the present invention;

FIG. 2 is a schematic diagram of the kinetics of an electric double layer capacitor according to the present invention;

fig. 3 is a schematic view of an equivalent circuit of an electric double layer capacitor according to the present invention.

Detailed Description

The present invention is described in further detail below.

The capacitor of the invention uses semiconductor ceramic as an electronic conductor layer to replace the traditional metal electrode to form an electric double layer capacitor structure without a built-in metal electrode of the electronic conductor layer-solid electrolyte layer-electronic conductor layer, uses a large amount of electric charge accumulation generated between the electronic conductor layer and the solid electrolyte layer to form energy storage, and uses a multilayer ceramic capacitor (MLCC) preparation process to improve the withstand voltage, thereby effectively constructing the electric double layer capacitor structure with large capacity, simple structure and easy processing and manufacturing. The invention has the advantages of large withstand voltage, low dielectric loss, high capacitance and good safety. The solid electrolyte and the semiconductor ceramic are combined, various novel energy storage devices can be designed, effective control of an interface between the solid electrolyte and the semiconductor ceramic is realized, and the solid electrolyte and the semiconductor ceramic are suitable for the technical fields of large-capacity energy storage technology and high-voltage-withstanding capacitor.

The invention relates to a high-performance double electric layer capacitor, which has a structure of a flat plate multilayer ceramic capacitor and comprises at least one electrolyte layer, wherein the electrolyte layer is inorganic solid electrolyte ceramic; in addition, at least two same conductor layers used as electrode substitutes are provided, and the conductor layers are electronic conductor ceramics; the basic structure of the capacitor is a sandwich structure formed by two conductor layers and an inorganic solid electrolyte, and is shown in figure 1.

The solid electrolyte ceramic is Li_3xLa_2/3-xTiO₃(LLTO) a polycrystalline structure ceramic, wherein x is 0-0.17; orThe electrolyte ceramic is Li_7-xLa₃Zr_2-xNb_xO₁₂(Nb-LLZO) polycrystalline structure ceramic, wherein x is 0-0.2; the conductor layer is made of CaMnO₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃One or more of a semiconducting ceramic; wherein x is 0-0.10.

Specifically, the electronic conductor layer serving as an electrode is cylindrical semiconductor ceramic with the diameter of 16-24 mm and the thickness of 100-200 mm, the cylindrical solid electrolyte ceramic with the diameter of 16-24 mm and the thickness of 100-200 mm serving as an ion conductor layer is included, the electronic conductor layer is arranged on the upper surface and the lower surface of the ion conductor layer respectively, and the electronic conductor layer completely covers the upper surface and the lower surface of the solid electrolyte ceramic.

The solid electrolyte ceramic is ABO₃Perovskite type Li_3xLa_2/3-xTiO₃(LLTO, x is 0.02 to 0.17) and garnet type Li_7-xLa₃Zr_2-xNb_xO₁₂(Nb-LLZO, x is 0-0.5), wherein the perovskite type LLTO is one or more of a cubic phase structure, a hexagonal phase structure, a tetragonal phase structure and an orthogonal phase structure, and the garnet type Nb-LLZO is one or more of a cubic phase structure and a tetragonal phase structure;

the electronic conductor is semiconductor ceramic SrTi_1-xNb_xO₃(x＝0.001～0.10，Nb：STO)、CaMnO₃、SnO₂、TiO₂And ZnO.

A method for preparing a ceramic double electric layer capacitor comprises the following steps:

1. preparation of solid electrolyte ceramic powder

1.1 the solid electrolyte is perovskite Li_3xLa_2/3-xTiO₃(LLTO, x is 0.02-0.167) cubic phase or tetragonal phase or garnet-type Li_7-xLa₃Zr_2-xNb_xO₁₂(Nb-LLZO, x is 0-0.5) one or more, selecting corresponding raw material powder meeting the stoichiometric ratio, weighing, adding zirconium dioxide ball milling beadsAnd putting ethanol into a ball milling tank for ball milling, introducing the mixed liquid into a glass vessel for drying, heating the dried powder to 900-1100 ℃ in an air atmosphere, wherein the heating rate is 0.5-5 ℃/min, the heat preservation time is 1-5 hours, and then sieving, wherein the particle size of a sieve is as follows: and 60-120 meshes, thus obtaining the corresponding pre-sintered powder of the tetragonal phase or cubic phase perovskite type LLTO solid electrolyte ceramic or garnet type Nb-LLZO solid electrolyte ceramic with uniform particles.

2. Addition of a glass phase

Preparation of Li according to the melt quenching preparation process₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅Glass powder;

2.1 lithium carbonate, boron oxide, silica, lithium phosphate as starting materials, according to Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅Accurately weighing each raw material according to a corresponding proportion, adding ethanol and zirconium dioxide balls, mixing for 2-12 hours in a ball milling tank, drying, grinding and sieving, wherein the particle size of a screen is as follows: 60-120 meshes to obtain evenly mixed Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅The original powder material.

2.2 mixing the Li obtained in step 2.1₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅Placing original powder into a crucible, carrying out high-temperature treatment at 1000-1200 ℃, wherein the heating rate is 2-5 ℃/min, the heat preservation time is not more than 6 hours, then taking out the crucible and a sample together by using a fire tongs at high temperature, and rapidly quenching in deionized water to obtain Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅A glass in a solid state.

2.3 reaction of Li obtained in step 2.2₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅Agate mortar for solid glassGrinding and sieving to obtain fine and uniform Li with a sieve mesh size of 100-300 meshes₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅And (3) glass powder.

Then adding Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅And (2) mixing the glass powder with the LLTO or Nb-LLZO in the step (1), namely adding ethanol and zirconium dioxide balls, mixing for 2-12 hours in a ball milling tank, drying, grinding and sieving, wherein the particle size of a screen is as follows: 60-120 meshes to obtain LLTO or Nb-LLZO ceramic pre-sintering powder containing a glass phase; wherein the glass powder accounts for 0.1-10 wt% of the LLTO or Nb-LLZO.

3. Preparation of electronic conductor ceramic powder

3.1, mixing Nb: STO or CaMnO₃Or SnO₂Or ZnO or TiO₂The raw materials of the material, such as strontium carbonate, niobium pentoxide, titanium dioxide, calcium carbonate, manganese dioxide, tin dioxide and zinc oxide are added with ethanol and zirconium dioxide balls according to corresponding metering ratios, mixed in a ball milling tank for 2-12 hours, dried, ground and sieved, and the particle size of a screen is as follows: 60-120 meshes to obtain uniformly mixed raw material powder.

3.2, heating the raw material powder obtained in the step 3.1 to 900-1200 ℃ in an air atmosphere, wherein the heating rate is 0.5-5 ℃/min, the heat preservation time is 1-5 hours, and then sieving, wherein the particle size of a sieve is as follows: and (3) 60-120 meshes, so that the corresponding Nb: STO or CaMnO₃Or SnO₂Or ZnO or TiO₂Pre-sintering powder of the electronic conductor.

4. Preparation of ceramic membranes

4.1, respectively adding a binder, a solvent and a plasticizer into the solid electrolyte powder and the electronic conductor powder obtained in the steps 2 and 3, and mixing by a wet method to prepare slurry, wherein the binder is polyethylene glycol butyral (PVB), the solvent is one or more of ethanol, methanol and propanol, ethylene glycol and glycerol, and the plasticizer is one or more of dibutyl phthalate (DBP) and dioctyl phthalate (DOP);

4.2, respectively adding the solid electrolyte slurry and the electronic conductor slurry obtained in the step 4.1 into a casting machine, namely coating the solid electrolyte slurry and the electronic conductor slurry on a PET plastic belt to form a uniform electrolyte slurry layer, wherein the thickness of the uniform electrolyte slurry layer is 20-500 micrometers, the speed of the steel belt of the casting machine is 5-30 mm/s, and the uniform electrolyte slurry layer is dried to obtain a compact LLTO or Nb-LLZO solid electrolyte ceramic membrane and Nb, wherein the compact LLTO or Nb-LLZO solid electrolyte ceramic membrane and Nb are 20-300 micrometers in thickness and 100 mm in width: STO or CaMnO₃Or SnO₂Or ZnO or TiO₂An electronic conductor ceramic membrane.

5. Co-firing

5.1, mixing one of the compact LLTO and Nb-LLZO solid electrolyte ceramic membranes with the thickness of 20-300 microns and the width of 100 mm obtained in the step 4 with Nb: STO, CaMnO₃、SnO₂ZnO and TiO₂One of the electronic conductor ceramic diaphragms is cut into thin wafers with the uniform size, the diameter of 8-16 mm and the thickness of 0.3-5 mm by a cutting machine.

5.2, laminating and molding the thin wafer obtained in the step 5.1 by using a dry press according to the sequence of an electronic conductor, a solid electrolyte and an electronic conductor, wherein the total number of layers is 3-30, and the pressure is 10-300 MPa;

and 5.3, placing the laminated sheet of the electronic conductor and the solid electrolyte obtained in the step 5.2 into a crucible, embedding the laminated sheet into a proper amount of lithium carbonate and zirconium dioxide mixed powder, sintering the laminated sheet in the atmosphere of air, hydrogen or nitrogen, wherein the sintering temperature is 1100-1500 ℃, the heating rate is 0.5-10 ℃/min, preserving heat for 0.5-36 hours, cooling the ceramic to room temperature at the speed of 0.5-10 ℃/min, and taking out the ceramic sheet to obtain the double-layer capacitor consisting of the electronic conductor and the solid electrolyte.

Through the above steps, a novel ceramic electric double layer capacitor can be obtained as shown in fig. 1.

The solid electrolyte has high ionic conductivity and low electronic conductivity, the difference of the order of magnitude is large, and the shielding effect on electrons can be realized, wherein the ionic conductivity of the LLTO-based solid electrolyte is about 10^-4S/cm, electron conductivity<10^-8S/cm; the Nb-LLZO based solid electrolyte has an ionic conductivity of about 2X 10^-4S/cm, electron conductivity of the same<10^-8S/cm. And the electronic conductor is a semiconductor ceramic material Nb: STO, CaMnO₃、ZnO、TiO₂And the typical electronic conductivity is about 1 to 10S/cm. The principle of the present capacitor is therefore to utilize e near the interface of the solid electrolyte and the electronic conductor^--Li⁺The electric double layer is used for storing energy, and an equivalent circuit of the metal-free internal electrode is constructed as a ceramic electric double layer capacitor shown in fig. 3. In contrast, in the prior art, the all-solid-state capacitor of the electric double layer capacitor is realized by using base metals such as Ni or Cu as electrodes and LLZO, and the like, and the limitation of the all-solid-state capacitor of such schemes is obvious due to the temperature limitation of metals, the complex process and the like. Therefore, the ceramic electric double layer capacitor without the metal inner electrode based on the solid electrolyte has higher voltage resistance and specific capacity and wider temperature use range, and can be used for energy storage in multiple fields. By further improving device performance, it is even possible to achieve use under severe conditions in the military and aerospace fields.

The present invention will be described in further detail with reference to examples.

Example 1

1. Preparation of solid electrolyte ceramic powder

1.1 lithium carbonate, lanthanum oxide and titanium dioxide as raw materials, according to the perovskite type Li_3xLa_2/3-xTiO₃Tetragonal polycrystal (Li) (LLTO, x ═ 0.167), i.e., Li_0.5La_0.5TiO₃After raw material powder is weighed according to the stoichiometric ratio, zirconium dioxide ball milling beads and ethanol are added and put into a ball milling tank for ball milling, mixed liquid is introduced into a glass vessel for drying, the dried powder is heated to 1000 ℃ in the air atmosphere, the heating rate is 5 ℃/min, the heat preservation time is 2 hours, and then the powder is sieved, and the particle size of a screen mesh is as follows: 70 meshes to obtain the corresponding pre-sintered powder of the tetragonal phase perovskite type LLTO solid electrolyte ceramic with uniform particles.

2. Addition of a glass phase

2.1 lithium carbonate, boron oxide, silica as starting materials, according to Li₂O-SiO₂-B₂O₃In a ratio of5: 2: 3 accurately weighing the raw materials, adding ethanol and zirconium dioxide balls, mixing for 12 hours in a ball milling tank, drying, and grinding through a 70-mesh screen to obtain Li with uniform mixing and relatively small granularity₂O-SiO₂-B₂O₃The original powder material.

2.2 mixing the Li obtained in step 2.1₂O-SiO₂-B₂O₃Placing original powder into a crucible, carrying out high-temperature treatment at 1100 ℃, wherein the heating rate is 10 ℃/min, the heat preservation time is 1 hour, then taking out the crucible and a sample together by using a fire tongs at high temperature, and rapidly quenching in deionized water to obtain LiO₂-SiO₂-B₂O₃A glass in a solid state.

2.3 reaction of Li obtained in step 2.2₂O-SiO₂-B₂O₃The solid glass was ground with an agate mortar and sieved through a 200 mesh sieve to obtain finer and uniform particle size glass frit. Then adding Li₂O-SiO₂-B₂O₃Mixing the glass powder and the LLTO, namely adding ethanol and zirconium dioxide balls, mixing for 6 hours in a ball milling tank, drying, grinding and sieving with a 70-mesh sieve to obtain LLTO ceramic pre-sintering powder containing a glass phase; wherein Li₂O-SiO₂-B₂O₃The mass percentage of the glass powder in the LLTO is 5 wt%.

3. Preparation of electronic conductor ceramic powder

3.1, mixing Nb: raw materials of STO material strontium carbonate, niobium pentoxide and titanium dioxide are in accordance with SrTi_0.999Nb_0.001O₃The raw materials are weighed according to the metering ratio, then ethanol and zirconium dioxide balls are added and mixed in a ball milling tank for 3 hours, and then the mixture is dried and ground and sieved by a 70-mesh sieve, so that the uniformly mixed raw material powder is obtained.

3.2, heating the raw material powder obtained in the step 3.1 to 1000 ℃ in an air atmosphere, wherein the heating rate is 5 ℃/min, the heat preservation time is 2 hours, and then sieving the raw material powder by a sieve of 60 meshes to obtain the corresponding Nb: STO electronic conductor pre-fired powder.

4. Preparation of ceramic membranes

4.1, mixing the LLTO ceramic pre-sintered powder containing the glass phase obtained in the step 2 and the step 3 with Nb: STO electronic conductor pre-firing powder is mixed by a wet method with a binder, a solvent and a plasticizer added, respectively, to prepare LLTO slurry and Nb: STO slurry, wherein the adhesive is polyethylene glycol butyral (PVB), the solvent is ethanol, and the plasticizer is dibutyl phthalate (DBP), wherein the mass ratio of the adhesive to the solvent to the plasticizer is 2: 7: 1.

4.2, mixing the LLTO slurry obtained in the step 4.1 and Nb: and respectively adding the STO slurry into a casting machine, namely coating the STO slurry on a PET plastic belt to form a uniform slurry layer, wherein the thickness of the slurry layer is 160 micrometers, the tape moving speed of a steel belt of the casting machine is 10 millimeters/second, and a compact LLTO solid electrolyte ceramic membrane with the thickness of 150 micrometers and the width of 100 millimeters and Nb are obtained by drying: STO electronic conductor ceramic diaphragms.

5. Co-firing

5.1, mixing the compact LLTO solid electrolyte ceramic membrane with the thickness of 150 microns and the width of 100 mm obtained in the step 4 with Nb: the STO electronic conductor ceramic diaphragm is cut into thin wafers with the uniform size, the diameter of 16 mm and the thickness of 1 mm by a cutting machine.

5.2, laminating and molding the thin wafer obtained in the step 5.1 by using a dry press according to the sequence of the electronic conductor, the solid electrolyte and the electronic conductor, wherein the total number of layers is 3, and the pressure is 100 MPa;

and 5.3, placing the laminated sheet of the electronic conductor and the solid electrolyte obtained in the step 5.2 into a crucible, embedding the laminated sheet into a proper amount of mixed powder of lithium carbonate and zirconium dioxide, sintering the laminated sheet in a hydrogen atmosphere at the sintering temperature of 1450 ℃ at the heating rate of 3 ℃/min for 4 hours, cooling the ceramic to room temperature at the speed of 3 ℃/min, and taking out the ceramic sheet to obtain the double-layer capacitor consisting of the electronic conductor and the solid electrolyte.

Example 2

1. Preparation of solid electrolyte ceramic powder

1.1 lithium carbonate, lanthanum oxide and titanium dioxide as raw materials, according to the perovskite type Li_3xLa_2/3-xTiO₃Tetragonal phase of (LLTO, x ═ 0.167), i.e. Li_0.5La_0.5TiO₃After raw material powder is weighed according to the stoichiometric ratio, zirconium dioxide ball milling beads and ethanol are added and put into a ball milling tank for ball milling, mixed liquid is introduced into a glass vessel for drying, the dried powder is heated to 1000 ℃ in the air atmosphere, the heating rate is 5 ℃/min, the heat preservation time is 2 hours, and then the powder is sieved, and the particle size of a screen mesh is as follows: 70 meshes to obtain the corresponding pre-sintered powder of the tetragonal phase perovskite type LLTO solid electrolyte ceramic with uniform particles.

2. Addition of a glass phase

2.1 lithium carbonate, boron oxide, silica as starting materials, according to Li₂O-SiO₂-B₂O₃The proportion is 5: 3: 2 accurately weighing the raw materials, adding ethanol and zirconium dioxide balls, mixing for 12 hours in a ball milling tank, drying, and grinding through a 70-mesh screen to obtain Li with uniform mixing and relatively small granularity₂O-SiO₂-B₂O₃The original powder material.

2.2 mixing the Li obtained in step 2.1₂O-SiO₂-B₂O₃Placing original powder into a crucible, carrying out high-temperature treatment at 1050 ℃, wherein the heating rate is 10 ℃/min, the heat preservation time is 1 hour, then taking out the crucible and a sample together by using a fire tongs at high temperature, and rapidly quenching in deionized water to obtain Li₂O-SiO₂-B₂O₃A glass in a solid state.

2.3 reaction of Li obtained in step 2.2₂O-SiO₂-B₂O₃The solid glass was ground with an agate mortar and sieved through a 200 mesh sieve to obtain finer and uniform particle size glass frit. Then adding Li₂O-SiO₂-B₂O₃Mixing the glass powder and the LLTO, namely adding ethanol and zirconium dioxide balls, mixing for 6 hours in a ball milling tank, drying, grinding and sieving with a 70-mesh sieve to obtain LLTO ceramic pre-sintering powder containing a glass phase; wherein Li₂O-SiO₂-B₂O₃The mass percentage of the glass powder in the LLTO is 7 wt%.

3. Preparation of electronic conductor ceramic powder

3.1 mixing CaMnO₃Calcium carbonate and manganese dioxide as raw materials of (CMO) material in accordance with CaMnO₃The raw materials are weighed according to the stoichiometric ratio, then ethanol and zirconium dioxide balls are added and mixed in a ball milling tank for 6 hours, and then the mixture is dried and ground and sieved by a 70-mesh sieve to obtain uniformly mixed raw material powder.

3.2, heating the raw material powder obtained in the step 3.1 to 1150 ℃ in an air atmosphere, wherein the heating rate is 3 ℃/min, the heat preservation time is 4 hours, and then sieving the raw material powder with a 70-mesh sieve to obtain the corresponding CMO electronic conductor pre-sintered powder.

4. Preparation of ceramic membranes

4.1, adding a binder, a solvent and a plasticizer into the LLTO powder and the CMO powder obtained in the steps 2 and 3 respectively, and performing wet processing according to the weight ratio of 2: 7: 1, wherein the binder is polyethylene glycol butyral (PVB), the solvent is ethanol, and the plasticizer is dibutyl phthalate (DBP).

And 4.2, respectively adding the LLTO slurry and the CMO slurry obtained in the step 4.1 into a casting machine, namely coating the slurry on a PET plastic belt to form a uniform slurry layer, wherein the thickness of the slurry layer is 160 micrometers, the tape moving speed of a steel belt of the casting machine is 10 millimeters/second, and drying to obtain a compact LLTO solid electrolyte ceramic membrane and a compact CMO electronic conductor ceramic membrane, the thickness of which is 150 micrometers and the width of which is 100 millimeters.

5. Co-firing

5.1, cutting the compact LLTO solid electrolyte ceramic membrane and the CMO electronic conductor ceramic membrane which are obtained in the step 4 and have the thickness of 150 microns and the width of 100 millimeters into thin wafers with the uniform size, the diameter of 16 millimeters and the thickness of 1 millimeter by using a cutting machine.

5.2, laminating and molding the thin wafer obtained in the step 5.1 by using a dry press according to the sequence of the electronic conductor, the solid electrolyte and the electronic conductor, wherein the total number of layers is 3, and the pressure is 110 MPa;

and 5.3, placing the laminated sheet of the electronic conductor and the solid electrolyte obtained in the step 5.2 into a crucible, embedding the laminated sheet into a proper amount of mixed powder of lithium carbonate and zirconium dioxide, sintering the laminated sheet in a hydrogen atmosphere at the sintering temperature of 1100 ℃ at the heating rate of 3 ℃/min, keeping the temperature for 10 hours, cooling the ceramic to the room temperature at the speed of 3 ℃/min, and taking out the ceramic sheet to obtain the electric double layer capacitor consisting of the electronic conductor and the solid electrolyte.

Example 3

1. Preparation of solid electrolyte ceramic powder

1.1 lithium carbonate, lanthanum oxide, zirconium oxide, titanium dioxide, niobium pentoxide as raw materials and in accordance with polycrystalline garnet-type Li_6.7La₃Zr_1.7Nb_0.3O₁₂(Nb-LLZO) weighing the raw material powder according to the stoichiometric ratio, adding zirconium dioxide ball milling beads and isopropanol, putting the mixture into a ball milling tank for ball milling, introducing the mixed liquid into a glass vessel for drying, heating the dried powder to 900 ℃ in air atmosphere, wherein the heating rate is 3 ℃/min, the heat preservation time is 6 hours, and then sieving the dried powder by a 60-mesh sieve to obtain the corresponding pre-sintered powder of the tetragonal-phase garnet type Nb-LLZO solid electrolyte ceramic with uniform particles.

2. Addition of a glass phase

2.1 lithium carbonate, boron oxide, silica, lithium phosphate as starting materials, according to Li₂O-SiO₂-P₂O₅The proportion is 5: 4: 1 accurately weighing the raw materials, adding ethanol and zirconium dioxide balls, mixing for 3 hours in a ball milling tank, drying, and grinding through a 70-mesh screen to obtain Li with uniform mixing and relatively small granularity₂O-SiO₂-P₂O₅The original powder material.

2.2 mixing the Li obtained in step 2.1₂O-SiO₂-P₂O₅Placing original powder into a crucible, carrying out high-temperature treatment at 1000 ℃, wherein the heating rate is 5 ℃/min, the heat preservation time is 3 hours, then taking out the crucible and a sample together by using a fire tongs at high temperature, and rapidly quenching in deionized water to obtain Li₂O-SiO₂-P₂O₅A glass in a solid state.

2.3 reaction of Li obtained in step 2.2₂O-SiO₂-P₂O₅Grinding the solid glass by using an agate mortar and passing throughAnd sieving with a 200-mesh sieve to obtain the glass powder with fine and uniform granularity. Then adding LiO₂-SiO₂-B₂O₃Mixing the glass powder and Nb-LLZO, namely adding ethanol and zirconium dioxide balls into a ball mill pot to mix for 6 hours, then drying, grinding and sieving with a 70-mesh sieve to obtain Nb-LLZO ceramic pre-sintered powder containing a glass phase, wherein LiO is₂-SiO₂-B₂O₃The mass percentage of the glass powder in the Nb-LLZO is 5 wt%.

3. Preparation of electronic conductor ceramic powder

3.1, mixing Nb: raw materials of STO material strontium carbonate, niobium pentoxide and titanium dioxide are in accordance with SrTi_0.991Nb_0.009O₃The raw materials are weighed according to the metering ratio, then ethanol and zirconium dioxide balls are added and mixed in a ball milling tank for 6 hours, and then the mixture is dried and ground and sieved by a 70-mesh sieve, so that the uniformly mixed raw material powder is obtained.

3.2, heating the raw material powder obtained in the step 3.1 to 1030 ℃ in an air atmosphere, wherein the heating rate is 4 ℃/min, the heat preservation time is 4 hours, and then sieving the raw material powder by a 60-mesh sieve to obtain the corresponding Nb: STO electronic conductor pre-fired powder.

4. Preparation of ceramic membranes

4.1, mixing the Nb-LLZO powder obtained in the step 2 and the step 3 with Nb: STO powder is added with a binder, a solvent and a plasticizer respectively and mixed by a wet method to prepare slurry, wherein the binder is polyethylene glycol butyral (PVB), the solvent is ethanol, and the plasticizer is dibutyl phthalate (DBP).

4.2, mixing the Nb-LLZO slurry obtained in the step 4.1 and Nb: and respectively adding the STO slurry into a casting machine, namely coating the STO slurry on a PET plastic belt to form a uniform slurry layer, wherein the thickness of the slurry layer is 160 micrometers, the belt travelling speed of a steel belt of the casting machine is 10 millimeters/second, and drying is carried out to obtain a compact Nb-LLZO solid electrolyte ceramic membrane with the thickness of 150 micrometers and the width of 100 millimeters, and the ratio of Nb: STO electronic conductor ceramic diaphragms.

5. Co-firing

5.1, mixing the dense Nb-LLZO solid electrolyte ceramic membrane with the thickness of 150 microns and the width of 100 millimeters obtained in the step 4 with Nb: the STO electronic conductor ceramic diaphragm is cut into thin wafers with the uniform size, the diameter of 16 mm and the thickness of 1 mm by a cutting machine.

5.2, laminating and molding the thin wafer obtained in the step 5.1 by using a dry press according to the sequence of an electronic conductor, a solid electrolyte and an electronic conductor, wherein the total number of layers is 6, and the pressure is 200 MPa;

and 5.3, placing the laminated sheet of the electronic conductor and the solid electrolyte obtained in the step 5.2 into a crucible, embedding the laminated sheet into a proper amount of mixed powder of Nb-LLZO raw material powder and zirconium dioxide, sintering the laminated sheet in a hydrogen atmosphere at the sintering temperature of 1430 ℃ and the heating rate of 3 ℃/min, keeping the temperature for 12 hours, cooling the ceramic to the room temperature at the speed of 3 ℃/min, and taking out the ceramic sheet to obtain the ceramic double-layer capacitor consisting of the electronic conductor and the solid electrolyte.

Example 4

Step 1: lithium carbonate, boron oxide, silicon dioxide in accordance with Li₂O-SiO₂-B₂O₃Heating the mixture from room temperature to 1000 ℃ at a heating rate of 2 ℃/min, keeping the temperature for 6 hours, quenching the mixture in deionized water to form solid glass, and grinding the solid glass to obtain 60-120-mesh Li₂O-SiO₂-B₂O₃And (3) glass powder.

Mixing lithium carbonate, lanthanum oxide and titanium dioxide according to Li_3xLa_2/3-xTiO₃Mixing, ball milling and drying the mixture, then heating the mixture to 900 ℃ in air atmosphere at the heating rate of 0.5 ℃/minute, and keeping the temperature for 5 hours to prepare the cubic phase structure perovskite Li_3xLa_2/3-xTiO₃Pre-burning powder of solid electrolyte;

mixing Li₂O-SiO₂-B₂O₃Glass powder and cubic phase structure perovskite type Li_3xLa_2/3-xTiO₃Mixing the solid electrolyte pre-sintering powder to obtain solid electrolyte powder; wherein x is 0.02;

lithium carbonate, lanthanum oxide, zirconium oxide, titanium dioxide and niobium pentoxide are mixed according to garnet type Li_7-xLa₃Zr_{2- x}Nb_xO₁₂Of (2) aMixing according to a metering ratio, ball-milling, drying, heating to 900 ℃ at a heating rate of 5 ℃/min in an air atmosphere, and keeping the temperature for 5 hours to prepare garnet Li with a cubic phase structure_7-xLa₃Zr_2-xNb_xO₁₂Pre-burning powder of solid electrolyte; wherein x is 0.

Step 2: preparing solid electrolyte powder into solid electrolyte slurry, and processing and forming the solid electrolyte slurry into an electrolyte ceramic membrane;

mixing calcium carbonate and manganese dioxide, ball-milling, drying, heating to 1100 ℃ in air atmosphere, and keeping the temperature for 1 hour to obtain CaMnO₃；

Mixing strontium carbonate, niobium pentoxide and titanium dioxide according to SrTi_1-xNb_xO₃The SrTi is obtained by metering, mixing, ball milling and drying, then heating to 1000 ℃ in air atmosphere and preserving heat for 2 hours_1-xNb_xO₃A semiconductor ceramic; wherein x is 0.001.

Adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Preparing one or more of the semiconductor ceramics into electronic conductor slurry, and processing and molding the electronic conductor slurry into an electronic conductor ceramic membrane; wherein x is 0.001;

and step 3: the solid electrolyte ceramic membrane is prepared by the following processes: grinding and sieving solid electrolyte powder, and then adding an adhesive, a solvent and a plasticizer to obtain solid electrolyte slurry; adding the solid electrolyte slurry into a casting machine, coating the casting machine on a PET plastic belt at the speed of 20 mm/s to form a slurry layer of 20-500 microns, and drying to obtain a solid electrolyte ceramic membrane with the thickness of 20-300 microns and the width of 100 mm;

the electronic conductor ceramic membrane is prepared by the following processes: adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Grinding one or more of the semiconductor ceramics, sieving, and adding an adhesive, a solvent and a plasticizer to obtain electronic conductor slurry; adding electronic conductor slurry into casting machineAnd coating the tape on a PET plastic tape at a tape travelling speed of 20 mm/s to form a 20-500 micron slurry layer, and drying to obtain the electronic conductor ceramic membrane with the thickness of 20-300 microns and the width of 100 mm.

Cutting the electronic conductor ceramic membrane and the electrolyte ceramic membrane, then sequentially laminating the electronic conductor, the ionic conductor and the electronic conductor, and finally sintering at 1500 ℃ for 0.5 hour to obtain the ceramic double-electric-layer capacitor.

Example 5

Step 1: lithium carbonate, boron oxide and silicon dioxide are mixed according to Li₂O-SiO₂-B₂O₃Heating the mixture from room temperature to 1200 ℃ at a heating rate of 5 ℃/min, keeping the temperature for 2 hours, quenching the mixture in deionized water to form solid glass, and grinding the solid glass to obtain 60-120-mesh Li₂O-SiO₂-B₂O₃。

Mixing lithium carbonate, lanthanum oxide and titanium dioxide according to Li_3xLa_2/3-xTiO₃Mixing, ball milling and drying, then heating to 1100 ℃ at the heating rate of 5 ℃/min in the air atmosphere, and keeping the temperature for 1 hour to prepare the perovskite Li of the hexagonal phase structure_3xLa_2/3-xTiO₃Pre-burning powder of solid electrolyte;

mixing Li₂O-SiO₂-B₂O₃Glass powder and cubic phase structure perovskite type Li_3xLa_2/3-xTiO₃Mixing the solid electrolyte pre-sintering powder to obtain solid electrolyte powder; wherein x is 0.1;

lithium carbonate, lanthanum oxide, zirconium oxide, titanium dioxide and niobium pentoxide are mixed according to garnet type Li_7-xLa₃Zr_{2- x}Nb_xO₁₂After mixing according to the stoichiometric ratio, ball milling and drying are carried out, then the temperature is raised to 1100 ℃ in the air atmosphere at the temperature rise rate of 0.5 ℃/minute, the heat preservation time is 1 hour, and the garnet type Li with the cubic phase structure is prepared_7-xLa₃Zr_2-xNb_xO₁₂Pre-burning powder of solid electrolyte; wherein x is 0.1.

Step 2: preparing solid electrolyte powder into solid electrolyte slurry, and processing and forming the solid electrolyte slurry into an electrolyte ceramic membrane;

mixing calcium carbonate and manganese dioxide, ball-milling, drying, heating to 1100 ℃ in air atmosphere, and keeping the temperature for 1 hour to obtain CaMnO₃；

Mixing strontium carbonate, niobium pentoxide and titanium dioxide according to SrTi_1-xNb_xO₃The SrTi is obtained by metering, mixing, ball milling and drying, then heating to 900 ℃ in air atmosphere and preserving the temperature for 5 hours_1-xNb_xO₃A semiconductor ceramic; wherein x is 0.10.

Adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Preparing one or more of the semiconductor ceramics into electronic conductor slurry, and processing and molding the electronic conductor slurry into an electronic conductor ceramic membrane; wherein x is 0.10;

and step 3: the solid electrolyte ceramic membrane is prepared by the following processes: grinding and sieving solid electrolyte powder, and then adding an adhesive, a solvent and a plasticizer to obtain solid electrolyte slurry; adding the solid electrolyte slurry into a casting machine, coating the casting machine on a PET plastic belt at the speed of 10 mm/s to form a slurry layer of 20-500 microns, and drying to obtain a solid electrolyte ceramic membrane with the thickness of 20-300 microns and the width of 100 mm;

the electronic conductor ceramic membrane is prepared by the following processes: adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Grinding one or more of the semiconductor ceramics, sieving, and adding an adhesive, a solvent and a plasticizer to obtain electronic conductor slurry; adding the electronic conductor slurry into a casting machine, coating the tape on a PET plastic tape at the tape-moving speed of 10 mm/s of the steel tape of the casting machine to form a slurry layer of 20-500 microns, and drying to obtain the electronic conductor ceramic membrane with the thickness of 20-300 microns and the width of 100 mm.

Cutting the electronic conductor ceramic membrane and the electrolyte ceramic membrane, then sequentially laminating the electronic conductor, the ionic conductor and the electronic conductor, and finally sintering at 900 ℃ for 36 hours to obtain the ceramic double-electric-layer capacitor.

Example 6

Step 1: lithium carbonate, silica and lithium phosphate according to Li₂O-SiO₂-P₂O₅Heating the mixture from room temperature to 1100 ℃ at a heating rate of 3 ℃/min, preserving heat for 3 hours, quenching the mixture in deionized water to form solid glass, and grinding the solid glass to obtain 60-120-mesh Li₂O-SiO₂-P₂O₅And (3) glass powder.

Mixing lithium carbonate, lanthanum oxide and titanium dioxide according to Li_3xLa_2/3-xTiO₃Mixing, ball milling and drying, then heating to 1000 ℃ at the heating rate of 2 ℃/min in the air atmosphere, and keeping the temperature for 3 hours to prepare the perovskite Li with the tetragonal phase structure_3xLa_2/3-xTiO₃Pre-burning powder of solid electrolyte;

mixing Li₂O-SiO₂-P₂O₅Glass powder and cubic phase structure perovskite type Li_3xLa_2/3-xTiO₃Mixing the solid electrolyte pre-sintering powder to obtain solid electrolyte powder; wherein x is 0.167;

lithium carbonate, lanthanum oxide, zirconium oxide, titanium dioxide and niobium pentoxide are mixed according to garnet type Li_7-xLa₃Zr_{2- x}Nb_xO₁₂After mixing according to the stoichiometric ratio, ball milling and drying are carried out, then the temperature is raised to 1000 ℃ in the air atmosphere at the temperature rise rate of 2 ℃/minute, the heat preservation time is 3 hours, and the garnet type Li with the cubic phase structure is prepared_7-xLa₃Zr_2-xNb_xO₁₂Pre-burning powder of solid electrolyte; wherein x is 0.17.

Step 2: preparing solid electrolyte powder into solid electrolyte slurry, and processing and forming the solid electrolyte slurry into an electrolyte ceramic membrane;

mixing calcium carbonate and manganese dioxide, ball-milling, drying, heating to 900 ℃ in air atmosphere, and keeping the temperature for 5 hours to obtain CaMnO₃；

Mixing strontium carbonate, niobium pentoxide and titanium dioxide according to SrTi_1-xNb_xO₃The SrTi is obtained by metering, mixing, ball milling and drying, then heating to 1100 ℃ in air atmosphere and preserving the temperature for 1 hour_1-xNb_xO₃A semiconductor ceramic; wherein x is 0.005.

Adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Preparing one or more of the semiconductor ceramics into electronic conductor slurry, and processing and molding the electronic conductor slurry into an electronic conductor ceramic membrane; wherein x is 0.005;

and step 3: the solid electrolyte ceramic membrane is prepared by the following processes: grinding and sieving solid electrolyte powder, and then adding an adhesive, a solvent and a plasticizer to obtain solid electrolyte slurry; adding the solid electrolyte slurry into a casting machine, coating the casting machine on a PET plastic belt at the speed of 30 mm/s to form a slurry layer of 20-500 microns, and drying to obtain a solid electrolyte ceramic membrane with the thickness of 20-300 microns and the width of 100 mm;

the electronic conductor ceramic membrane is prepared by the following processes: adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Grinding one or more of the semiconductor ceramics, sieving, and adding an adhesive, a solvent and a plasticizer to obtain electronic conductor slurry; adding the electronic conductor slurry into a casting machine, coating the tape on a PET plastic tape at the tape-moving speed of 30 mm/s of the steel tape of the casting machine to form a slurry layer of 20-500 microns, and drying to obtain the electronic conductor ceramic membrane with the thickness of 20-300 microns and the width of 100 mm.

Cutting the electronic conductor ceramic membrane and the electrolyte ceramic membrane, then sequentially laminating the electronic conductor, the ionic conductor and the electronic conductor, and finally sintering at 1100 ℃ for 30 hours to obtain the ceramic double-electric-layer capacitor.

Example 7

Step 1: lithium carbonate, silica and lithium phosphate according to Li₂O-SiO₂-P₂O₅Heating the mixture from room temperature to 1050 ℃ at a heating rate of 4 ℃/min, keeping the temperature for 5 hours, quenching the mixture in deionized water to form solid glass, and grinding the solid glass to obtain 60-120-mesh Li₂O-SiO₂-P₂O₅And (3) glass powder.

Mixing lithium carbonate, lanthanum oxide and titanium dioxide according to Li_3xLa_2/3-xTiO₃Mixing, ball milling and drying, then heating to 950 ℃ at the heating rate of 3 ℃/min in the air atmosphere, and keeping the temperature for 4 hours to prepare the perovskite Li of the orthorhombic structure_3xLa_2/3-xTiO₃Pre-burning powder of solid electrolyte;

mixing Li₂O-SiO₂-P₂O₅Glass powder and cubic phase structure perovskite type Li_3xLa_2/3-xTiO₃Mixing the solid electrolyte pre-sintering powder to obtain solid electrolyte powder; wherein x is 0.06;

lithium carbonate, lanthanum oxide, zirconium oxide, titanium dioxide and niobium pentoxide are mixed according to garnet type Li_7-xLa₃Zr_{2- x}Nb_xO₁₂After mixing according to the stoichiometric ratio, ball milling and drying are carried out, then the temperature is raised to 1050 ℃ in the air atmosphere at the temperature rise rate of 4 ℃/minute, the heat preservation time is 2 hours, and the garnet type Li with the tetragonal phase structure is prepared_7-xLa₃Zr_2-xNb_xO₁₂Pre-burning powder of solid electrolyte; wherein x is 0.05.

Step 2: preparing solid electrolyte powder into solid electrolyte slurry, and processing and forming the solid electrolyte slurry into an electrolyte ceramic membrane;

mixing calcium carbonate and manganese dioxide, ball-milling, drying, heating to 1000 ℃ in air atmosphere, and keeping the temperature for 3 hours to obtain CaMnO₃；

Mixing strontium carbonate, niobium pentoxide and titanium dioxide according to SrTi_1-xNb_xO₃The SrTi is obtained by metering, mixing, ball milling and drying, then heating to 1000 ℃ in air atmosphere and preserving heat for 4 hours_1-xNb_xO₃A semiconductor ceramic; wherein x is 0.05.

Adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Preparing one or more of the semiconductor ceramics into electronic conductor slurry, and processing and molding the electronic conductor slurry into an electronic conductor ceramic membrane; wherein x is 0.05;

and step 3: the solid electrolyte ceramic membrane is prepared by the following processes: grinding and sieving solid electrolyte powder, and then adding an adhesive, a solvent and a plasticizer to obtain solid electrolyte slurry; adding the solid electrolyte slurry into a casting machine, coating the casting machine on a PET plastic belt at the speed of 5 mm/s to form a slurry layer of 20-500 microns, and drying to obtain a solid electrolyte ceramic membrane with the thickness of 20-300 microns and the width of 100 mm;

the electronic conductor ceramic membrane is prepared by the following processes: adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Grinding one or more of the semiconductor ceramics, sieving, and adding an adhesive, a solvent and a plasticizer to obtain electronic conductor slurry; adding the electronic conductor slurry into a casting machine, coating the tape on a PET plastic tape at the tape-moving speed of 5 mm/s of the steel tape of the casting machine to form a slurry layer of 20-500 microns, and drying to obtain the electronic conductor ceramic membrane with the thickness of 20-300 microns and the width of 100 mm.

Cutting the electronic conductor ceramic membrane and the electrolyte ceramic membrane, then sequentially laminating the electronic conductor, the ionic conductor and the electronic conductor, and finally sintering at 1200 ℃ for 23 hours to obtain the ceramic double-electric-layer capacitor.

The all-solid-state double electric layer capacitor is characterized in that an electrolyte layer is arranged between two adjacent conductor layers, the capacitor with the double electric layer structure, which is simple in structure and easy to process and manufacture, is effectively constructed by using the interface characteristics of electronic conductor ceramics as electrode layers and solid electrolytes, and the safety problems that the traditional double electric layer capacitor cannot resist high temperature, is easy to burn and the like are avoided because the electrode layers and the solid electrolyte layers are made of solid ceramics. In addition, when an electric field is applied to the capacitor, a large amount of electron enrichment is formed near the interface of the electrolyte and the electron conductor layer, and the electrons cannot pass through the electrolyte layer to form a large built-in electric field, so that ions of the electrolyte are pushed to rapidly move, a very large polarization process is generated (as shown in fig. 2), and a large capacitance is obtained. In addition, because the structure utilizes conductive ceramics as an electronic conductor layer to replace the traditional electrode material, the MLCC without metal internal electrodes in series connection can be more easily completed, so that the withstand voltage of the MLCC is greatly increased, and compared with the traditional capacitor at present, the capacity of the MLCC is larger due to higher withstand voltage and dielectric constant. Therefore, the all-solid-state electric double layer capacitor will become a next-generation safer large-capacity capacitor.

Claims (10)

1. A ceramic double electric layer capacitor is characterized by comprising at least two conductor layers and at least one electrolyte layer, wherein one electrolyte layer is arranged between every two adjacent conductor layers; each conductor layer is made of semiconductor conductive ceramics; each electrolyte layer is an inorganic solid electrolyte ceramic.

2. A ceramic electric double layer capacitor according to claim 1, wherein the inorganic solid electrolyte ceramic is Li_3xLa_2/3-xTiO₃A polycrystalline structure ceramic, wherein x is 0.02 to 0.167; or the inorganic solid electrolyte ceramic is Li_{7- x}La₃Zr_2-xNb_xO₁₂A polycrystalline structure ceramic, wherein x is 0 to 0.2; the conductor layer is made of CaMnO₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃One or more of a semiconducting ceramic; wherein x is 0.001-0.10.

3. The ceramic electric double layer capacitor of claim 2, wherein the Li is Li_3xLa_2/3-xTiO₃The polycrystalline structure ceramic is ABO₃Cubic phase structure of perovskite, perovskiteOne or more of the hexagonal phase structure of (a), the tetragonal phase structure of perovskite, and the orthorhombic phase structure of perovskite; the Li_7-xLa₃Zr_2-xNb_xO₁₂The polycrystalline structure ceramic is one or more of garnet-type cubic phase structure and garnet-type tetragonal phase structure; the solid electrolyte ceramic is Li_3xLa_2/3-xTiO₃The ceramic has a polycrystalline structure, wherein x is 0.10 to 0.17.

4. A method for preparing a ceramic double electric layer capacitor is characterized by comprising the following steps:

step 1: mixing Li₂O-SiO₂-B₂O₃Glass powder and Li₂O-SiO₂-P₂O₅One of glass powder and perovskite type Li_3xLa_2/3-xTiO₃Mixing the solid electrolyte pre-sintering powder to obtain solid electrolyte powder; wherein x is 0.02-0.167;

or mixing Li₂O-SiO₂-B₂O₃Glass powder and Li₂O-SiO₂-P₂O₅One of the glass powders and garnet type Li_7-xLa₃Zr_{2- x}Nb_xO₁₂Mixing the solid electrolyte pre-sintering powder to obtain solid electrolyte powder; wherein x is 0-0.5;

step 2: preparing solid electrolyte powder into solid electrolyte slurry, and processing and forming the solid electrolyte slurry into an electrolyte ceramic membrane;

adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Preparing one or more of the semiconductor ceramics into electronic conductor slurry, and processing and molding the electronic conductor slurry into an electronic conductor ceramic membrane; wherein x is 0.001-0.10;

and step 3: and cutting the electronic conductor ceramic membrane and the electrolyte ceramic membrane, sequentially laminating the electronic conductor, the ionic conductor and the electronic conductor in sequence, and finally sintering to obtain the ceramic double-electric-layer capacitor.

5. The method of claim 1, wherein the ceramic double layer capacitor is prepared by the method of the present invention,

in step 1, perovskite type Li_3xLa_2/3-xTiO₃In cubic, hexagonal, tetragonal or orthorhombic phase structure, garnet-type Li_7-xLa₃Zr_2-xNb_xO₁₂Is in a cubic phase or tetragonal phase structure;

perovskite type Li_3xLa_2/3-xTiO₃The solid electrolyte pre-sintering powder is prepared by the following processes: mixing lithium carbonate, lanthanum oxide and titanium dioxide according to Li_3xLa_2/3-xTiO₃Mixing, ball-milling and drying the mixture according to the stoichiometric ratio, then heating the mixture to 900-1100 ℃ in air atmosphere, and keeping the temperature for 1-5 hours to prepare solid electrolyte ceramic pre-sintering powder;

garnet type Li_7-xLa₃Zr_2-xNb_xO₁₂The solid electrolyte pre-sintering powder is prepared by the following processes: lithium carbonate, lanthanum oxide, zirconium oxide, titanium dioxide and niobium pentoxide are mixed according to garnet type Li_7-xLa₃Zr_2-xNb_xO₁₂Mixing the raw materials according to the stoichiometric ratio, ball-milling, drying, heating to 900-1100 ℃ in an air atmosphere, and keeping the temperature for 1-5 hours to obtain solid electrolyte ceramic pre-sintering powder; wherein x is 0 to 0.17.

6. The method of claim 5, wherein the ceramic double layer capacitor is prepared by the method of the present invention,

preparation of perovskite type Li_3xLa_2/3-xTiO₃Solid electrolyte pre-sintered powder and garnet-type Li_7-xLa₃Zr_2-xNb_xO₁₂The heating rate of the solid electrolyte pre-sintering powder is 0.5-5 ℃/min.

7. The method of claim 4, wherein the ceramic double layer capacitor is prepared by the method of the present invention,

in step 1, Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅The glass powder is prepared by the following steps:

several of lithium carbonate, boron oxide, silicon dioxide and lithium phosphate are according to Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅Mixing the above stoichiometric ratio, keeping the temperature at 1000-1200 ℃ for not more than 6 hours, quenching to form solid glass, and grinding to obtain Li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅And (3) glass powder.

8. The method for manufacturing a ceramic electric double layer capacitor according to claim 7, wherein the temperature is raised from room temperature to 1000-1200 ℃ at a temperature raising rate of 2-5 ℃/min; quenching in deionized water; li₂O-SiO₂-B₂O₃Or Li₂O-SiO₂-P₂O₅The glass powder is 60-120 meshes.

9. The method of claim 4, wherein in step 2, the CaMnO is present₃Is prepared by the following steps: mixing calcium carbonate and manganese dioxide, ball-milling, drying, heating to 900-1100 ℃ in air atmosphere, and keeping the temperature for 1-5 hours to obtain CaMnO₃；

SrTi_1-xNb_xO₃The semiconductor ceramic is prepared by the following processes: mixing strontium carbonate, niobium pentoxide and titanium dioxide according to SrTi_1-xNb_xO₃The SrTi is obtained by metering, mixing, ball milling and drying, then heating to 900-1100 ℃ in air atmosphere, and keeping the temperature for 1-5 hours_1-xNb_xO₃A semiconductor ceramic; wherein x is 0.001-0.10.

10. The method of claim 4, wherein the solid electrolyte ceramic membrane is prepared by: grinding and sieving solid electrolyte powder, and then adding an adhesive, a solvent and a plasticizer to obtain solid electrolyte slurry; adding the solid electrolyte slurry into a casting machine, coating the solid electrolyte slurry on a PET plastic belt to form a slurry layer, and drying to obtain a solid electrolyte ceramic membrane;

the electronic conductor ceramic membrane is prepared by the following processes: adding CaMnO to the mixture₃、SnO₂、TiO₂、ZnO、SrTi_1-xNb_xO₃Grinding one or more of the semiconductor ceramics, sieving, and adding an adhesive, a solvent and a plasticizer to obtain electronic conductor slurry; adding the electronic conductor slurry into a casting machine, coating the electronic conductor slurry on a PET plastic belt to form a slurry layer, and drying to obtain an electronic conductor ceramic membrane;

in the preparation process of the solid electrolyte ceramic membrane and the electronic conductor ceramic membrane, the thickness of a slurry layer is 20-500 micrometers, the tape-moving speed of a steel tape of a casting machine is 5-30 mm/s, the thickness of the solid electrolyte ceramic membrane and the thickness of the electronic conductor ceramic membrane are 20-300 micrometers, and the width of the solid electrolyte ceramic membrane and the width of the electronic conductor ceramic membrane are 100 millimeters;

the specific conditions of sintering are as follows: the sintering temperature is 900-1500 ℃, and the sintering time is 0.5-36 hours.

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