Preparation method and application of oxide glass electrode of lithium ion capacitor

Abstract

The invention discloses a preparation method and application of an oxide glass electrode of a lithium ion capacitor, and belongs to the technical field of oxide glass electrodes, and the preparation method of the oxide glass mainly comprises the following steps: weighing glass raw materials according to glass composition, uniformly mixing, heating, melting, cooling and annealing, grinding the annealed glass into glass powder, and preparing for preparing an electrode plate; the preparation method comprises the following steps: weighing an active substance, a conductive agent and a binder in proportion, mixing in a ball milling tank, and dropwise adding a proper amount of dispersant for ball milling; blade-coating the slurry on a metal aluminum foil current collector for drying; and cutting the dried pole piece into electrode slices by using a slicing machine to prepare for assembling the lithium ion capacitor. According to the preparation method and application of the oxide glass electrode of the lithium ion capacitor, the obtained oxide glass electrode shows excellent electrochemical performance, meanwhile, the production process is simple, no pollution is caused to the environment, good application prospects are achieved, and more choices are provided for electrode materials of the lithium ion capacitor.

Description

A method for preparing and applying an oxide glass electrode for lithium-ion capacitors. Technical Field

[0001] This invention relates to the field of oxide glass electrode technology, and in particular to a method for preparing and applying an oxide glass electrode for lithium-ion capacitors. Background Technology

[0002] The global energy system is undergoing a profound transformation. The large-scale application of renewable energy and the rapid development of electrified transportation have placed unprecedentedly stringent demands on the energy density, power density, cycle stability, and safety of energy storage technologies. Lithium-ion capacitors (LICs), as a novel energy storage device, cleverly combine the core advantages of lithium-ion batteries and supercapacitors: compared to lithium-ion batteries, they offer faster charging and discharging speeds, higher safety, longer cycle life, and superior high-temperature resistance; compared to supercapacitors, they possess higher energy density, a wider operating voltage range, and a lower self-discharge rate. Therefore, they have broad application prospects in key areas such as new energy vehicles and rail transportation, and their research value and industrialization potential are increasing daily.

[0003] The energy storage mechanism of lithium-ion capacitors mainly relies on the surface double layer formed on the electrolyte surface during charging and discharging, and the synergistic effect of redox reactions occurring on the electrode surface. Currently, the negative electrode materials for lithium-ion capacitors are relatively mature, with carbon-based materials such as graphite and hard carbon commonly used, which can meet the basic performance requirements of the devices. However, there is still a significant bottleneck in positive electrode materials. Existing positive electrode materials are mostly surface adsorption-desorption type activated carbon, which has a low energy storage capacity. This defect directly limits the further improvement of the energy density of lithium-ion capacitors, making it difficult to adapt to the practical application requirements of the new energy field for energy storage devices that "balance high power density and high energy density," becoming a core technical problem restricting the large-scale promotion of lithium-ion capacitors.

[0004] Therefore, providing a high-capacity cathode material suitable for lithium-ion capacitors and breaking through existing technological bottlenecks is an important problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing and applying an oxide glass electrode for lithium-ion capacitors. Oxide glass (an amorphous material) exhibits a significant pseudocapacitive effect during charge and discharge. This effect refers to the fact that during lithium-ion charge and discharge, the capacity is jointly controlled by capacitance and diffusion, which can effectively improve the energy storage performance of the material. Oxide glass has a three-dimensional random network structure with short-range order and long-range disorder, and possesses a large free volume. This makes the volume change of the material small during lithiation and delithiation, and it is not prone to structural damage. At the same time, its surface has a large number of lithium-ion active sites, which can quickly form lithium-ion transport channels, thus exhibiting excellent rate performance and cycle stability. These characteristics make it an ideal choice for the positive electrode material of lithium-ion capacitors. This invention proposes to use oxide glass material as the positive electrode of lithium-ion capacitors and assemble it with commercial graphite or commercial hard carbon negative electrodes to form lithium-ion capacitors, thereby broadening the selection of electrode materials for lithium-ion capacitors (LICs).

[0006] This invention provides a method for preparing an oxide glass electrode for a lithium-ion capacitor, comprising the following steps: S1, preparation of oxide glass: weighing glass raw materials according to the glass composition, mixing them evenly and pouring them into an alumina crucible; placing the crucible in a muffle furnace and heating and holding it in an air atmosphere to melt the glass into a molten liquid; pouring the molten glass onto a preheated copper plate in an air atmosphere to cool and form glass; placing the copper plate containing the glass into an annealing furnace and annealing it at a temperature 30-50°C lower than the glass transition temperature; grinding the annealed glass into glass powder to prepare for the preparation of electrode sheets; S2, preparation of the oxide glass electrode for a lithium-ion capacitor. Preparation: Weigh the active material, conductive agent, and binder according to the proportion, put them into a ball mill jar, mix them, and add 1-2 ml of dispersant until the slurry can just flow smoothly; put the ball mill jar into a ball mill and ball mill; scrape the slurry onto the aluminum foil current collector; first put it into a forced-air drying oven at 60℃ to 80℃ to dry it until the surface of the electrode slurry no longer flows, then put it into a vacuum drying oven at 80℃ to 120℃ for vacuum drying for 12 to 16 hours, at which time the oxide glass electrode sheet of the lithium-ion capacitor will be completely dry; cut the dried electrode sheet into electrode sheets with a diameter of 14 mm using a slicer to prepare for the assembly of lithium-ion capacitors.

[0007] Preferably, the glass composition in S1 is 20 mol% Li2O, 30-38 mol% MoO3, 2-10 mol% MnO2, 10 mol% B2O3, and 30 mol% P2O5 (abbreviated as LMMBP).

[0008] Preferably, the heating and holding conditions in S1 under air atmosphere are as follows: the temperature is increased to the glass melting temperature at a rate of 5°C / min, and held for 30 minutes, with the glass melting temperature being 1000°C.

[0009] Preferably, in S2, the active material is LMMBP, the conductive agent is acetylene black, the binder is PVDF, and the dispersant is NMP; the mass ratio of active material: conductive agent: binder is 8:1:1.

[0010] Preferably, in S2, the conditions for placing the ball mill jar into the ball mill for ball milling are: ball milling at a speed of 350 r / min for 4 hours.

[0011] An application of the oxide glass electrode for lithium-ion capacitors as described above is provided for the preparation of lithium-ion capacitors. The steps are as follows: In a glove box, the positive electrode shell, positive electrode plate, separator, negative electrode plate, nickel mesh, and negative electrode shell are assembled in that order, and an appropriate amount of electrolyte is added; the button-type lithium-ion capacitor is sealed using a sealing machine.

[0012] Preferably, the positive electrode is made of oxide glass, and the negative electrode is made of commercial graphite or commercial hard carbon.

[0013] Therefore, the present invention adopts the above-mentioned method for preparing and applying an oxide glass electrode for lithium-ion capacitors, and the beneficial effects are as follows: (1) The present invention prepares oxide glass in an air atmosphere, and then uses the glass to prepare an oxide glass electrode. Due to the three-dimensional structural characteristics of short-range order and long-range disorder and the large free volume of glass, the structure changes little during charging and discharging and there are more active sites, exhibiting pseudocapacitive effect, and showing good rate performance and cycle stability. This provides a variety of choices for lithium-ion capacitor electrode materials.

[0014] (2) Lithium-ion capacitors assembled with oxide glass electrodes and commercial graphite or hard carbon electrodes exhibit good rate performance and cycle stability. They also possess high energy density at high power density. They have promising research and development prospects.

[0015] (3) The production process of this invention is simple and does not pollute the environment.

[0016] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0017] Figure 1 is a schematic diagram of the structure of the lithium-ion capacitor of the present invention; Figure 2 is the charge-discharge curve of the oxide glass lithium-ion capacitor in Embodiment 1 of the present invention; Figure 3 is the time-voltage curve of the oxide glass lithium-ion capacitor in Embodiment 1 of the present invention; Figure 4 is the cycle diagram of the oxide glass lithium-ion capacitor in Embodiment 1 of the present invention. Detailed Implementation

[0018] To better understand the above technical solutions, a detailed description of the solutions will be provided below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0019] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0020] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0021] Example 1 S1, Preparation of oxide glass; S11, Weigh 20 mol% Li2O, 30 mol% MoO3, 10 mol% MnO2, 10 mol% B2O3, and 30 mol% P2O5, mix them evenly and pour them into an alumina crucible.

[0022] S12. Place the crucible in a muffle furnace and raise the temperature to 1000°C at 5°C / min in an air atmosphere. Hold the temperature for 30 minutes to melt the mixture into a glass melt.

[0023] S13. In an air atmosphere, molten glass is poured onto a preheated copper plate and cooled to form glass.

[0024] S14. Place the copper plate containing the glass into an annealing furnace and anneal it at a temperature 40°C lower than the glass transition temperature to obtain an oxide glass named LMMBP-1.

[0025] S15. Grind the annealed glass into glass powder to prepare for the preparation of electrode sheets.

[0026] S2. Prepare the oxide glass electrode for lithium-ion capacitors; S21. Weigh LMMBP-1 as the active material, acetylene black as the conductive agent, and PVDF as the binder according to the mass ratio of active material: conductive agent: binder = 8:1:1. Place them in a ball mill jar, mix them, and add 1.5 ml of dispersant N-methyl-2-pyrrolidone (NMP).

[0027] S22. Place the ball mill jar into the ball mill and ball mill at 350 r / min for 4 hours.

[0028] S23. Apply the slurry to the aluminum foil current collector.

[0029] S24. First, place the electrode paste in a forced-air drying oven at 70°C until the surface of the electrode paste no longer flows. Then, place it in a vacuum oven at 100°C for vacuum drying for 14 hours. At this time, the entire oxide glass electrode sheet of the lithium-ion capacitor will be completely dry. S25. Cut the dried electrode sheet into electrode sheets with a diameter of 14mm using a slicer to prepare for the assembly of lithium-ion capacitors.

[0030] S3. Assemble the lithium-ion capacitor (graphite / / LMMBP-1); S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-1 glass electrode prepared above, and the negative electrode was a commercial graphite negative electrode.

[0031] S32. Seal the lithium-ion capacitor with a sealing machine.

[0032] S4. Perform electrochemical performance testing on the lithium-ion capacitor; use the Blue Electric testing system to perform charge-discharge testing on the lithium-ion capacitor (graphite / / LMMBP-1) prepared in this embodiment.

[0033] Under constant current charging and discharging conditions with a cutoff voltage of 1.5-4.0V and a g / L, -1 The lithium-ion capacitor (graphite / / LMMBP-1) was subjected to cyclic testing at current density. The first charge-discharge curve is shown in Figure 2, and the discharge specific capacitance is 102 mA hg. -1 The first six cycles are shown in Figure 3, demonstrating good cycle reversibility of the lithium-ion capacitor. As shown in Figure 4, after 70 cycles, the discharge specific capacitance is 87 mA hg. -1 At approximately 850,000 kg -1 At a power density of 86Wh / kg, it provides 86Wh / kg -1 Energy density.

[0034] Example 2 S1, Preparation of oxide glass; S11, Weigh 20 mol% Li2O, 34 mol% MoO3, 6 mol% MnO2, 10 mol% B2O3, and 30 mol% P2O5, mix them evenly and pour them into an alumina crucible.

[0035] S12. Place the crucible in a muffle furnace and raise the temperature to 1000°C at 5°C / min in an air atmosphere. Hold the temperature for 30 minutes to melt the mixture into a glass melt.

[0036] S13. In an air atmosphere, molten glass is poured onto a preheated copper plate and cooled to form glass.

[0037] S14. Place the copper plate containing the glass into an annealing furnace and anneal it at a temperature 50°C lower than the glass transition temperature to obtain an oxide glass named LMMBP-2.

[0038] S15. Grind the annealed glass into glass powder to prepare for the preparation of electrode sheets.

[0039] S2. Prepare the oxide glass electrode for lithium-ion capacitors; S21. Weigh LMMBP-2 as the active material, acetylene black as the conductive agent, and PVDF as the binder according to the mass ratio of active material: conductive agent: binder = 8:1:1. Place them in a ball mill jar, mix them, and add 1.5 ml of dispersant N-methyl-2-pyrrolidone (NMP).

[0040] S22. Place the ball mill jar into the ball mill and ball mill at 350 r / min for 4 hours.

[0041] S23. Apply the slurry to the aluminum foil current collector.

[0042] S24. First, place the electrode paste in a forced-air drying oven at 70°C until the surface of the electrode paste no longer flows. Then, place it in a vacuum oven at 100°C for vacuum drying for 14 hours. At this time, the entire oxide glass electrode sheet of the lithium-ion capacitor will be completely dry. S25. Cut the dried electrode sheet into electrode sheets with a diameter of 14mm using a slicer to prepare for the assembly of lithium-ion capacitors.

[0043] S3. Assemble the lithium-ion capacitor (graphite / / LMMBP-2); S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-2 glass electrode prepared above, and the negative electrode was a commercial graphite negative electrode.

[0044] S32. Seal the lithium-ion capacitor with a sealing machine.

[0045] S4. Perform electrochemical performance testing on the lithium-ion capacitor; use the Blue Electric testing system to perform charge-discharge testing on the lithium-ion capacitor (graphite / / LMMBP-2) prepared in this embodiment.

[0046] Under constant current charging and discharging conditions with a cutoff voltage of 1.5-4.0V and a g / L, -1 Cyclic testing was performed on a glass lithium-ion capacitor (graphite / / LMMBP-2) at current density, and the first-cycle discharge specific capacitance was 76 mA hg. -1 After 70 cycles, the specific capacity is 57 mA hg. -1 In approximately 80W kg -1 At a power density of 64Wh / kg, it provides 64Wh / kg -1 Energy density.

[0047] Example 3 S1, Preparation of oxide glass; S11, Weigh 20 mol% Li2O, 36 mol% MoO3, 4 mol% MnO2, 10 mol% B2O3, and 30 mol% P2O5, mix them evenly and pour them into an alumina crucible.

[0048] S12. Place the crucible in a muffle furnace and raise the temperature to 1000°C at 5°C / min in an air atmosphere. Hold the temperature for 30 minutes to melt the mixture into a glass melt.

[0049] S13. In an air atmosphere, molten glass is poured onto a preheated copper plate and cooled to form glass.

[0050] S14. Place the copper plate containing the glass into an annealing furnace and anneal it at a temperature 30°C lower than the glass transition temperature to obtain an oxide glass named LMMBP-3.

[0051] S15. Grind the annealed glass into glass powder to prepare for the preparation of electrode sheets.

[0052] S2. Prepare the oxide glass electrode for lithium-ion capacitors; S21. Weigh LMMBP-3 as the active material, acetylene black as the conductive agent, and PVDF as the binder according to the mass ratio of active material: conductive agent: binder = 8:1:1. Place them in a ball mill jar, mix them, and add 1.5 ml of dispersant N-methyl-2-pyrrolidone (NMP).

[0053] S22. Place the ball mill jar into the ball mill and ball mill at 350 r / min for 4 hours.

[0054] S23. Apply the slurry to the aluminum foil current collector.

[0055] S24. First, place the electrode paste in a forced-air drying oven at 70°C until the surface of the electrode paste no longer flows. Then, place it in a vacuum oven at 100°C for vacuum drying for 14 hours. At this time, the entire oxide glass electrode sheet of the lithium-ion capacitor will be completely dry. S25. Cut the dried electrode sheet into electrode sheets with a diameter of 14mm using a slicer to prepare for the assembly of lithium-ion capacitors.

[0056] S3. Assemble the lithium-ion capacitor (graphite / / LMMBP-3); S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-3 glass electrode prepared above, and the negative electrode was a commercial graphite negative electrode.

[0057] S32. Seal the lithium-ion capacitor with a sealing machine.

[0058] S4. Electrochemical performance testing of the lithium-ion capacitor; charge-discharge testing of the glass lithium-ion capacitor (graphite / / LMMBP-3) prepared in this embodiment was performed using a Blue Electric testing system. The constant current charge-discharge was conducted at a cutoff voltage of 1.5-4.0V and a discharge rate of 0.1A g. -1 Cyclic testing was performed on a glass lithium-ion capacitor (graphite / / LMMBP-3) at current density, and the first-cycle discharge specific capacitance was 65 mA hg. -1 After 70 cycles, the specific capacity is 46 mA hg. -1 At approximately 820,000 kg -1 At a power density of 55Wh / kg, it provides 55Wh / kg -1 Energy density.

[0059] Example 4 S1, Preparation of oxide glass; S11, Weigh 20 mol% Li2O, 38 mol% MoO3, 2 mol% MnO2, 10 mol% B2O3, and 30 mol% P2O5, mix them evenly and pour them into an alumina crucible.

[0060] S12. Place the crucible in a muffle furnace and raise the temperature to 1000°C at 5°C / min in an air atmosphere. Hold the temperature for 30 minutes to melt the mixture into a glass melt.

[0061] S13. In an air atmosphere, molten glass is poured onto a preheated copper plate and cooled to form glass.

[0062] S14. Place the copper plate containing the glass into an annealing furnace and anneal it at a temperature 30°C lower than the glass transition temperature to obtain an oxide glass named LMMBP-4.

[0063] S15. Grind the annealed glass into glass powder to prepare for the preparation of electrode sheets.

[0064] S2. Prepare the oxide glass electrode for lithium-ion capacitors; S21. Weigh LMMBP-4 as the active material, acetylene black as the conductive agent, and PVDF as the binder according to the mass ratio of active material: conductive agent: binder = 8:1:1. Place them in a ball mill jar, mix them, and add 1.5 ml of dispersant N-methyl-2-pyrrolidone (NMP).

[0065] S22. Place the ball mill jar into the ball mill and ball mill at 350 r / min for 4 hours.

[0066] S23. Apply the slurry to the aluminum foil current collector.

[0067] S24. First, place the electrode paste in a forced-air drying oven at 70°C until the surface of the electrode paste no longer flows. Then, place it in a vacuum oven at 100°C for vacuum drying for 14 hours. At this time, the entire oxide glass electrode sheet of the lithium-ion capacitor will be completely dry. S25. Cut the dried electrode sheet into electrode sheets with a diameter of 14mm using a slicer to prepare for the assembly of lithium-ion capacitors.

[0068] S3. Assemble the lithium-ion capacitor (graphite / / LMMBP-4); S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-4 glass electrode prepared above, and the negative electrode was a commercial graphite negative electrode.

[0069] S32. Seal the lithium-ion capacitor with a sealing machine.

[0070] S4. Electrochemical performance testing of the lithium-ion capacitor; charge-discharge testing of the glass lithium-ion capacitor (graphite / / LMMBP-4) prepared in this embodiment was performed using a blue electric current testing system. The constant current charge-discharge was conducted at a cutoff voltage of 1.5-4.0V and a discharge rate of 0.1A g. -1Cyclic testing was performed on a glass lithium-ion capacitor (graphite / / LMMBP-4) at current density, and the first-cycle discharge specific capacitance was 53 mA hg. -1 After 70 cycles, the specific capacity is 38 mA hg. -1 At approximately 820,000 kg -1 At a power density of 45Wh / kg, it provides 45Wh / kg -1 Energy density.

[0071] Example 5 S1, Preparation of oxide glass; S11, Weigh 20 mol% Li2O, 32 mol% MoO3, 8 mol% MnO2, 10 mol% B2O3, and 30 mol% P2O5, mix them evenly and pour them into an alumina crucible.

[0072] S12. Place the crucible in a muffle furnace and raise the temperature to 1000°C at 5°C / min in an air atmosphere. Hold the temperature for 30 minutes to melt the mixture into a glass melt.

[0073] S13. In an air atmosphere, molten glass is poured onto a preheated copper plate and cooled to form glass.

[0074] S14. Place the copper plate containing the glass into an annealing furnace and anneal it at a temperature 40°C lower than the glass transition temperature to obtain an oxide glass named LMMBP-5.

[0075] S15. Grind the annealed glass into glass powder to prepare for the preparation of electrode sheets.

[0076] S2. Prepare the oxide glass electrode for lithium-ion capacitors; S21. Weigh LMMBP-5 as the active material, acetylene black as the conductive agent, and PVDF as the binder according to the mass ratio of active material: conductive agent: binder = 8:1:1. Place them in a ball mill jar, mix them, and add 1.5 ml of dispersant N-methyl-2-pyrrolidone (NMP).

[0077] S22. Place the ball mill jar into the ball mill and ball mill at 350 r / min for 4 hours.

[0078] S23. Apply the slurry to the aluminum foil current collector.

[0079] S24. First, place the electrode paste in a forced-air drying oven at 70°C until the surface of the electrode paste no longer flows. Then, place it in a vacuum oven at 100°C for vacuum drying for 14 hours. At this time, the entire oxide glass electrode sheet of the lithium-ion capacitor will be completely dry. S25. Cut the dried electrode sheet into electrode sheets with a diameter of 14mm using a slicer to prepare for the assembly of lithium-ion capacitors.

[0080] S3. Assemble the lithium-ion capacitor (graphite / / LMMBP-5); S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-5 glass electrode prepared above, and the negative electrode was a commercial graphite negative electrode.

[0081] S32. Seal the lithium-ion capacitor with a sealing machine.

[0082] S4. Perform electrochemical performance testing on the lithium-ion capacitor; use the Blue Electric testing system to perform charge-discharge testing on the glass lithium-ion capacitor (graphite / / LMMBP-5) prepared in this embodiment.

[0083] Under constant current charging and discharging conditions with a cutoff voltage of 1.5-4.0V and a g / L, -1 Cyclic testing of a lithium-ion capacitor (graphite / / LMMBP-5) at current density showed a discharge specific capacitance of 110 mA hg. -1 After 70 cycles, the specific capacity is 94 mA hg. -1 At approximately 850,000 kg -1 At a power density of 93Wh / kg, it provides 93Wh / kg -1 Energy density.

[0084] Example 6: A lithium-ion capacitor (hard carbon / / LMMBP-1) was prepared by combining the LMMBP-1 oxide glass electrode prepared in Example 1 with a commercial hard carbon electrode. The preparation methods of the oxide glass and the oxide glass electrode of the lithium-ion capacitor were the same as those in Example 1.

[0085] S3. Assemble the lithium-ion capacitor; S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-1 glass electrode prepared above, and the negative electrode was a commercially available hard carbon negative electrode.

[0086] S32. Seal the lithium-ion capacitor with a sealing machine.

[0087] S4. Perform electrochemical performance testing on the lithium-ion capacitor; use the Blue Electricity testing system to perform charge-discharge testing on the glass lithium-ion capacitor (hard carbon / / LMMBP-1) prepared in this embodiment.

[0088] Under constant current charging and discharging conditions with a cutoff voltage of 1.5-4.0V and a g / L, -1 Cyclic testing of a glass lithium-ion capacitor (hard carbon / / LMMBP-1) at current density showed a first-cycle discharge specific capacitance of 95 mA hg. -1 After 70 cycles, the specific capacity is 67 mA hg. -1 At approximately 840,000 kg -1 At a power density of 80Wh / kg, it provides 80Wh / kg -1 Energy density.

[0089] Example 7: A lithium-ion capacitor (hard carbon / / LMMBP-2) was prepared by combining the LMMBP-2 oxide glass electrode prepared in Example 2 with a commercial hard carbon electrode. The preparation methods of the oxide glass and the oxide glass electrode of the lithium-ion capacitor were the same as in Example 2.

[0090] S3. Assemble the lithium-ion capacitor; S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-2 glass electrode prepared above, and the negative electrode was a commercially available hard carbon negative electrode.

[0091] S32. Seal the lithium-ion capacitor with a sealing machine.

[0092] S4. Perform electrochemical performance testing on the lithium-ion capacitor; use the Blue Electricity testing system to perform charge-discharge testing on the glass lithium-ion capacitor (hard carbon / / LMMBP-2) prepared in this embodiment.

[0093] Under constant current charging and discharging conditions with a cutoff voltage of 1.5-4.0V and a g / L, -1 Cyclic testing of a glass lithium-ion capacitor (hard carbon / / LMMBP-2) at current density showed a first-cycle discharge specific capacitance of 67 mA hg. -1 After 70 cycles, the specific capacity is 50 mA hg. -1 In approximately 80W kg -1 At a power density of 57Wh / kg, it provides 57Wh / kg -1 Energy density.

[0094] Example 8: A lithium-ion capacitor (hard carbon / / LMMBP-3) was prepared by combining the LMMBP-3 oxide glass electrode prepared in Example 3 with a commercial hard carbon electrode. The preparation methods of the oxide glass and the oxide glass electrode of the lithium-ion capacitor were the same as those in Example 3.

[0095] S3. Assemble the lithium-ion capacitor; S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-3 glass electrode prepared above, and the negative electrode was a commercially available hard carbon negative electrode.

[0096] S32. Seal the lithium-ion capacitor with a sealing machine.

[0097] S4. Perform electrochemical performance testing on the lithium-ion capacitor; use the Blue Electricity testing system to perform charge-discharge testing on the glass lithium-ion capacitor (hard carbon / / LMMBP-3) prepared in this embodiment.

[0098] Under constant current charging and discharging conditions with a cutoff voltage of 1.5-4.0V and a g / L, -1 Cyclic testing of a glass lithium-ion capacitor (hard carbon / / LMMBP-3) at current density showed a first-cycle discharge specific capacitance of 55 mA hg. -1 After 70 cycles, the specific capacity is 40 mA hg. -1 At approximately 840,000 kg -1 At a power density of 46Wh / kg, it provides 46Wh / kg -1 Energy density.

[0099] Example 9: A lithium-ion capacitor (hard carbon / / LMMBP-4) was prepared by combining the LMMBP-4 oxide glass electrode prepared in Example 4 with a commercial hard carbon electrode. The preparation methods of the oxide glass and the oxide glass electrode of the lithium-ion capacitor were the same as those in Example 4.

[0100] S3. Assemble the lithium-ion capacitor; S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-4 glass electrode prepared above, and the negative electrode was a commercially available hard carbon negative electrode.

[0101] S32. Seal the lithium-ion capacitor with a sealing machine.

[0102] S4. Perform electrochemical performance testing on the lithium-ion capacitor; use the Blue Electricity testing system to perform charge-discharge testing on the glass lithium-ion capacitor (hard carbon / / LMMBP-4) prepared in this embodiment.

[0103] Under constant current charging and discharging conditions with a cutoff voltage of 1.5-4.0V and a g / L, -1 Cyclic testing of a glass lithium-ion capacitor (hard carbon / / LMMBP-4) at current density showed a first-cycle discharge specific capacitance of 50 mA hg. -1 After 70 cycles, the specific capacity is 34 mA hg. -1 At approximately 820,000 kg -1 At a power density of 40Wh / kg, it provides 40Wh / kg -1 Energy density.

[0104] Example 10: A lithium-ion capacitor (hard carbon / / LMMBP-5) was prepared by combining the LMMBP-5 oxide glass electrode prepared in Example 5 with a commercial hard carbon electrode. The preparation methods of the oxide glass and the oxide glass electrode of the lithium-ion capacitor were the same as in Example 5.

[0105] S3. Assemble the lithium-ion capacitor; S31. In the glove box, assemble the capacitor in the following order: positive electrode shell 1, positive electrode plate 2, separator 3, negative electrode plate 4, nickel mesh 5, and negative electrode shell 6, and add an appropriate amount of electrolyte (1 mol·L⁻¹). -1 A mixed electrolyte of ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC) of LiPF6 (volume ratio of EC, DMC, and EMC is 1:1:1) was used. The positive electrode was the LMMBP-5 glass electrode prepared above, and the negative electrode was a commercially available hard carbon negative electrode.

[0106] S32. Seal the lithium-ion capacitor with a sealing machine.

[0107] S4. Perform electrochemical performance testing on the lithium-ion capacitor; use the Blue Electric testing system to perform charge-discharge testing on the glass lithium-ion capacitor (hard carbon / / LMMBP-5) prepared in this embodiment.

[0108] Under constant current charging and discharging conditions with a cutoff voltage of 1.5-4.0V and a g / L, -1 Cyclic testing was performed on a glass lithium-ion capacitor (hard carbon / / LMMBP-5) at current density, and the first-cycle discharge specific capacitance was 103 mA hg. -1 After 70 cycles, the specific capacity is 76 mA hg. -1 At approximately 840,000 kg -1At a power density of 90Wh / kg, it provides 90Wh / kg -1 Energy density.

[0109] Therefore, this invention employs the aforementioned method and application for preparing an oxide glass electrode for lithium-ion capacitors. Oxide glass is prepared in an air atmosphere, and then an oxide glass electrode is fabricated using this glass. Due to the three-dimensional structure of glass—characterized by short-range order and long-range disorder—and its large free volume, glass exhibits minimal structural changes and more active sites during charge and discharge, demonstrating a pseudocapacitive effect and exhibiting excellent rate performance and cycle stability. This provides a diverse range of electrode materials for lithium-ion capacitors. Lithium-ion capacitors assembled from oxide glass electrodes and commercially available graphite or hard carbon electrodes exhibit excellent rate performance and cycle stability. They also possess high energy density at high power densities, demonstrating promising research and development prospects. The production process of this invention is simple and environmentally friendly.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing an oxide glass electrode for a lithium-ion capacitor, characterized in that, Includes the following steps: S1. Preparation of oxide glass: Weigh the glass raw materials according to the glass composition, mix them evenly and pour them into an alumina crucible; Place the crucible in a muffle furnace and heat it in air to melt the glass into a molten liquid. Pour the molten glass onto a preheated copper plate in air to cool and form glass. Place the copper plate containing the glass into an annealing furnace and anneal it at a temperature 30-50°C below the glass transition temperature. Grind the annealed glass into glass powder to prepare for the preparation of electrode sheets. S2. Preparation of oxide glass electrodes for lithium-ion capacitors: Weigh the active material, conductive agent, and binder according to the proportion, place them in a ball mill jar, mix them, and add 1-2 ml of dispersant. Place the ball mill jar into a ball mill and ball mill. Coat the slurry onto a metal aluminum foil current collector. First, place it in a forced-air drying oven at 60°C to 80°C to dry it until the surface of the electrode slurry no longer flows. Then, place it in a vacuum oven at 80°C to 120°C to dry it for 12 to 16 hours. Cut the dried electrode sheet into electrode sheets with a diameter of 14 mm using a slicer to prepare for the assembly of lithium-ion capacitors.

2. The method for preparing an oxide glass electrode for a lithium-ion capacitor according to claim 1, characterized in that, The glass composition described in S1 is 20 mol% Li2O, 30-38 mol% MoO3, 2-10 mol% MnO2, 10 mol% B2O3, and 30 mol% P2O5.

3. The method for preparing an oxide glass electrode for a lithium-ion capacitor according to claim 1, characterized in that, In S1, the heating and holding conditions under air atmosphere are as follows: the temperature is increased to the glass melting temperature at a rate of 5℃ / min, and held for 30 minutes. The glass melting temperature is 1000℃.

4. The method for preparing an oxide glass electrode for a lithium-ion capacitor according to claim 1, characterized in that, In S2, the active material is LMMBP, the conductive agent is acetylene black, the binder is PVDF, and the dispersant is NMP; the mass ratio of active material: conductive agent: binder is 8:1:

1.

5. The method for preparing an oxide glass electrode for a lithium-ion capacitor according to claim 1, characterized in that, In S2, the conditions for placing the ball mill jar into the ball mill are to ball mill for 4 hours at a rotation speed of 350 r / min.

6. The application of an oxide glass electrode for a lithium-ion capacitor prepared by the method according to any one of claims 1-5, characterized in that, The steps for preparing lithium-ion capacitors are as follows: In a glove box, assemble the positive electrode shell, positive electrode plate, separator, negative electrode plate, nickel mesh, and negative electrode shell in that order, and add an appropriate amount of electrolyte; seal the button-type lithium-ion capacitor with a sealing machine.

7. The application of the oxide glass electrode for lithium-ion capacitors according to claim 6, characterized in that, The positive electrode is made of oxide glass, and the negative electrode is made of commercial graphite or commercial hard carbon.

8. A lithium-ion capacitor oxide glass electrode prepared by the preparation method according to any one of claims 1-5.

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