Sulfur-containing heterocyclic triptycenone organic battery positive electrode material and preparation method thereof

Abstract

The invention relates to a sulfur-containing heterocyclic triptycenone organic positive electrode molecule and a preparation method thereof. The molecular design is a propeller type structure formed by bridged expansion of benzene rings on side wings of triptycenone through thioether bonds. Furthermore, 2, 3, 6, 7, 14, 15-hexachlorotriptycenone is connected with one of 2, 3-difluorobenzoquinone, 2, 3-naphthoquinone dichloride, 2, 3-anthraquinone dichloride, 6, 7-dichloroquinoxaline-5, 8-diketone and 2, 3-dichloro-5, 8-dihydroxynaphthalene-1, 4-diketone through a thioether bond to form a propeller type triptycenone molecule of the sulfur-containing heterocyclic triptycenone compound. The obtained sulfur-containing heterocyclic triptycenone organic positive electrode molecule forms a two-dimensional supramolecular polymer under the pi-pi interaction of side wings, the problem of dissolution of the sulfur-containing heterocyclic triptycenone organic positive electrode molecule in an ether electrolyte is relieved, and the sulfur-containing heterocyclic triptycenone organic positive electrode molecule shows excellent charge-discharge cycle stability. And meanwhile, the weak Van der Waals force between the two-dimensional layers is beneficial to rapid transmission of metal ions, and excellent rate capability is realized. The electrochemical active positive electrode material provided by the invention can realize high-capacity, high-rate and long-cycle-life organic battery performance.

Description

Technical Field

[0001] The invention relates to the field of secondary battery materials, and in particular to a sulfur-containing heterocyclic triptycenequinone electrochemically active organic positive electrode material and a preparation method and application thereof. Background Art

[0002] In order to meet the growing demand for energy storage, the development of new batteries with fast charging capabilities has become a key technical challenge. The materials used for the electrodes significantly affect the charging and discharging speed of ion batteries. Traditional lithium-ion batteries are often based on transition metal oxides and graphite materials, resulting in low power density and long charging time, which is not conducive to the development of power batteries. At the same time, the limited availability of transition metals and their harmfulness to the environment lead to high production costs while not meeting the needs of sustainable development.

[0003] Organic redox active materials composed of carbon, oxygen, hydrogen and nitrogen, which are abundant on the earth, show advantages such as high theoretical capacity, flexible structural design and environmental friendliness, making organic secondary batteries promising to become one of the alternatives for sustainable energy storage. The reported organic electrode materials mainly include conductive polymers, organic sulfur compounds, organic free radicals, quinone compounds and the like. Among them, quinone compounds have the advantages of high energy density and good reversibility. Patents such as CN111909008A and CN116454278A invented a series of quinone organic small molecule positive electrode materials, but their battery capacity decayed rapidly in cycle tests, which is due to the serious dissolution problem of organic small molecules in organic electrolytes. Adv.Sci.2015,2,1500124, Angew.Chem.Int.Ed.2024,e202412452 and other articles proposed that making organic small molecule compounds into organic polymers or covalent organic frameworks (COFs) materials effectively alleviates the dissolution problem of small molecules. However, polymers and COFs have low electronic conductivity, and COFs usually have long ion transport paths. Especially under fast charging conditions, it is difficult for ions to reach the active sites buried deep inside the one-dimensional channels, which will inevitably lead to insufficient utilization of redox active sites, thereby reducing the utilization of active sites and the rate performance of the battery. Summary of the invention

[0004] The main purpose of the present invention is to provide a sulfur-containing heterocyclic triptycenequinone electrochemically active positive electrode material and a preparation method thereof, and to apply it to an organic metal battery to solve the problems of easy solubility of organic small molecule positive electrode materials and poor ion diffusion kinetics.

[0005] The present invention adopts the following technical solutions:

[0006] A sulfur-containing heterocyclic triptycenequinone electrochemically active molecule comprises a propeller-type triptycenequinone formed by extending the side flanks of a 2,3,6,7,14,15-hexachlorotriptycenequinone compound through a thioether bond bridge.

[0007] Specifically, the sulfur-containing heterocyclic triptycenequinone electrochemically active molecule includes a propeller-shaped triptycenequinone formed by connecting 2,3,6,7,14,15-hexachlorotriptycenequinone with any one of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione through a nucleophilic substitution reaction.

[0008] The present invention also provides a method for preparing a sulfur-containing heterocyclic triptycenequinone electrochemically active organic positive electrode material, comprising combining three reaction substrates by a solvothermal method to obtain a propeller-type triptycenequinone formed by sulfide bond bridge-type extended flanks of the quinone compound, wherein the three reaction substrates are 2,3,6,7,14,15-hexachlorotriptycenequinone, sodium sulfide nonahydrate and at least one quinone halogen compound that can react with the above two compounds to form a sulfide bond.

[0009] Specifically, the propeller-type triptycenequinone structural material is obtained by reacting 2,3,6,7,14,15-hexachlorotriptycenequinone with any one of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione. Sodium sulfide nonahydrate is added to an organic solvent to connect 2,3,6,7,14,15-hexachlorotriptycenequinone with any one of the above monomers through a thioether bond to form a propeller-type triptycenequinone molecule. The synthetic reaction formula is as follows:

[0010]

[0011] Furthermore, the method for preparing the electrochemically active molecule of triptycenequinone containing a sulfur heterocycle comprises the following steps:

[0012] Step 1): 2,3,6,7,14,15-hexachlorotriptylenquinone, sodium sulfide nonahydrate, and an organic solvent are added to a reaction container, and the oxygen in the solution is removed by freezing / vacuuming for three times, and the reaction is carried out at a temperature of 60 to 90° C. for 1 to 3 hours to obtain a dark green reaction mixture;

[0013] Step 2): adding any one of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione monomers to the mixed solution, freezing / vacuuming for three times to remove oxygen from the solution, and continuing to react at a temperature of 90 to 120° C. for 36 to 64 hours to obtain a brown reaction mixture;

[0014] Step 3): The organic solvent in the brown reaction mixture is evaporated, and the obtained solid is washed with deionized water, ethanol, and tetrahydrofuran in sequence and dried to obtain the target triptycenequinone compound.

[0015] Furthermore, in step 1), the organic solvent is any one of dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide, and the quantitative molar ratio of the 2,3,6,7,14,15-hexachlorotriptylenquinone to the sodium sulfide nonahydrate is 1:6 to 1:6.5.

[0016] Furthermore, in step 2), the quantitative molar ratio of the monomer addition amount of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione to 2,3,6,7,14,15-hexachlorotriptycenequinone is 4:1 to 5:1.

[0017] A positive electrode sheet comprises 45-70 wt% of electrochemically active molecules of triptycenequinone containing sulfur heterocycles, 20-45 wt% of conductive additives and 5-10 wt% of a binder.

[0018] An organic metal battery comprises a positive electrode, a negative electrode, a separator and an electrolyte.

[0019] Furthermore, the negative electrode is a lithium metal negative electrode, a zinc metal negative electrode or a sodium metal negative electrode.

[0020] Furthermore, the conductive additive is one of carbon nanotubes, conductive carbon black, and acetylene black, and the binder is one of polyvinylidene fluoride and polytetrafluoroethylene.

[0021] Furthermore, the electrolyte is lithium bis(trifluoromethanesulfonyl)imide dissolved in a mixed solvent of 1,3-dioxolane and 1,2-dimethoxyethane.

[0022] The present invention has the following beneficial effects:

[0023] The present invention provides a sulfur-containing heterocyclic triptycene-based organic positive electrode material and a preparation method thereof, which realizes the long life, high energy density and high power density of an organic secondary battery. Tripterycenequinone is used as a precursor, and the flanks of the triptycenequinone molecule are extended, so that the flanks of adjacent molecules can undergo supramolecular self-assembly under a strong π-π interaction to form a two-dimensional supramolecular polymer. The van der Waals force between the two-dimensional supramolecular polymer layers is weak. During the charge and discharge process, the interlayer spacing is easily expanded, so that ions can be quickly transmitted to the active sites through the interlayers. The advantages include: 1. Alleviating the dissolution problem of the organic positive electrode material and improving the long cycle stability performance; 2. While maintaining the long cycle stability performance, achieving very excellent rate performance; 3. Having abundant active sites and a higher voltage platform, it has a higher theoretical capacity and energy density. The present invention obtains a sulfur-containing heterocyclic triptycenequinone organic positive electrode material, which significantly improves the cycle stability performance of the organic positive electrode material, and at the same time has a fast ion transmission mechanism and excellent rate performance, which has important practical significance for promoting the development and application of organic positive electrode materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a molecular structure diagram of triptycenequinone containing a sulfur heterocycle in an embodiment of the present invention;

[0025] Figure 2 The liquid phase nuclear magnetic resonance of the sulfur-containing heterocyclic triptycenequinone organic molecule of Example 1 of the present invention is 1 H spectrum;

[0026] Figure 3 The solid-state nuclear magnetic resonance of the triptycenequinone organic molecule containing sulfur heterocycle of Example 1 of the present invention is 13 C spectrum;

[0027] Figure 4 is a mass spectrum of the sulfur-containing heterocyclic triptycenequinone organic molecule of Example 1 of the present invention;

[0028] Figure 5 This is an infrared absorption spectrum of the sulfur-containing heterocyclic triptycenequinone organic molecule of Example 1 of the present invention;

[0029] Figure 6 This is a scanning electron microscope morphology image of the sulfur-containing heterocyclic triptycenequinone organic molecule of Example 1 of the present invention;

[0030] Figure 7 This is a charge and discharge curve diagram of a sulfur-containing heterocyclic triptycenequinone organic cathode / lithium metal battery of a test example of the present invention;

[0031] Figure 8 This is a rate test performance diagram of a sulfur-containing heterocyclic triptycenequinone organic cathode / lithium metal battery of a test example of the present invention;

[0032] Fig. 9 This is a test diagram of the long cycle stability performance of the sulfur-containing heterocyclic triptycenequinone organic cathode / lithium metal battery of the test example of the present invention; DETAILED DESCRIPTION

[0033] To make the purpose, technical solution and advantages of the present invention clearer, the present invention is described in detail below in conjunction with the embodiments and drawings. It should be emphasized that the following description is only exemplary and is not intended to limit the scope of the present invention and its application.

[0034] An embodiment of the present invention provides a sulfur-containing heterocyclic triptycenequinone organic positive electrode material, wherein the active material is a propeller-type triptycenequinone formed by extending the flanks of quinone compounds through sulfide bonds. In some embodiments, the material is obtained by reacting 2,3,6,7,14,15-hexachlorotriptycenequinone with any one of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione.

[0035] In some of the embodiments, the synthesis steps of preparing the sulfur-containing heterocyclic triptycenequinone organic cathode material specifically include the following steps:

[0036] 2,3,6,7,14,15-hexachlorotriptylenquinone, sodium sulfide nonahydrate and an organic solvent are added to a reaction container, and the oxygen in the solution is removed by freezing / vacuuming for three times, and the reaction is carried out at a temperature of 60 to 90° C. for 1 to 3 hours to obtain a dark green reaction mixture. Any one of 2,3-difluorobenzoquinone, 2,3-dichloro-1,4-naphthoquinone, 2,3-dichloro-1,4-anthracenedione, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione monomers is then added to the mixture, and the oxygen in the solution is removed by freezing / vacuuming for three times, and the reaction is continued at a temperature of 60 to 90° C. for 36 to 64 hours to obtain a brown reaction mixture. Finally, the organic solvent in the brown reaction mixture is evaporated, and the obtained solid is washed with deionized water, ethanol, and tetrahydrofuran in sequence and dried (for example, at 100° C. for 24 hours) to obtain the target triptycenequinone compound.

[0037] In some embodiments, the organic solvent is any one of dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0038] In some of the embodiments, the quantitative molar ratio of 2,3,6,7,14,15-hexachlorotriptylenquinone to sodium sulfide nonahydrate is 1:6 to 1:6.5.

[0039] In some of the embodiments, the quantitative molar ratio of the monomer addition amount of 2,3-difluorobenzoquinone, 2,3-dichloro-1,4-naphthoquinone, 2,3-dichloro-1,4-anthracene dione, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione to 2,3,6,7,14,15-hexachlorotriptylenquinone is 4:1 to 5:1.

[0040] The embodiment of the present invention further provides a positive electrode sheet, comprising 45-70 wt % of electrochemically active molecules of triptycenequinone containing sulfur heterocycles, 20-45 wt % of conductive additives, and 5-10 wt % of a binder.

[0041] In some embodiments, the organic battery is one of an organic lithium metal battery, an organic sodium metal battery and an organic zinc metal battery.

[0042] The embodiment of the present invention further provides a method for preparing the triptycenequinone positive electrode sheet containing sulfur heterocycle, comprising the following steps:

[0043] The electrochemically active positive electrode material of the sulfur-containing heterocyclic triptycenequinone, the conductive agent and the binder are wet-ground and mixed evenly in N-methylpyrrolidone in a certain proportion, and then evenly coated on the current collector, placed in a blast oven for drying, cut, and further dried in a vacuum oven to obtain the positive electrode sheet.

[0044] In some embodiments, the method for preparing the sulfur-containing heterocyclic triptycenequinone positive electrode sheet comprises the following steps:

[0045] The electrochemically active sulfur-containing heterocyclic triptycenequinone molecule, the conductive agent and the binder are mixed in N-methylpyrrolidone to form a uniform slurry, which is then coated on the current collector and pre-dried in a blast oven at 80 to 100° C. for 5 hours, then cut to a diameter of 12 mm and dried in a vacuum oven at 100° C. for 24 to 36 hours to obtain the positive electrode sheet.

[0046] In some of the embodiments, the conductive agent includes but is not limited to carbon nanotubes, conductive carbon black, acetylene black, etc., the binder includes but is not limited to polyvinylidene fluoride, polytetrafluoroethylene, etc., and the current collector includes aluminum foil, carbon-coated aluminum foil, carbon felt, etc.

[0047] The embodiment of the present invention further provides an organic metal battery, comprising a positive electrode, a metal negative electrode, a separator and an electrolyte, wherein the positive electrode adopts the triptycenequinone positive electrode sheet containing sulfur heterocycle.

[0048] In some of the embodiments, the separator is a glass fiber separator, a polypropylene separator, etc., and the electrolyte is lithium trifluoromethanesulfonamide dissolved in a mixed solvent of 1,3-dioxolane and 1,2-dimethoxyethane in a volume ratio of 1:1.

[0049] Specific embodiments of the present invention are described below.

[0050] A sulfur-containing heterocyclic triptycenequinone organic battery positive electrode material and a preparation method thereof according to an embodiment of the present invention include the following steps: adding a certain amount of 2,3,6,7,14,15-hexachlorotriptycenequinone, sodium sulfide nonahydrate and N,N-dimethylformamide solvent into a Shrek tube, wherein the quantitative molar ratio of 2,3,6,7,14,15-hexachlorotriptycenequinone to sodium sulfide nonahydrate is 1:6 to 1:6.5, performing freezing / vacuuming cycles three times to remove oxygen from the solution, and reacting at a temperature of 60 to 90° C. for 1 to 3 hours to obtain a dark green reaction mixed solution. After cooling, any one of 2,3-difluorobenzoquinone, 2,3-dichloro-1,4-naphthoquinone, 2,3-dichloro-1,4-anthracenedione, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione monomers is added to the mixed solution, and the quantitative molar ratio of the monomer to 2,3,6,7,14,15-hexachlorotriptylenequinone is 4:1 to 5:1. The solution is frozen / vacuumed three times to remove oxygen, and the solution is stirred and heated at 90 to 120° C. for 36 to 64 hours to obtain a brown reaction mixture. Finally, the organic solvent in the brown reaction mixture is evaporated, and the obtained solid is washed with deionized water, ethanol, and tetrahydrofuran in turn and dried at 100° C. for 24 hours to obtain the target triptylenequinone compound.

[0051] The method for preparing a positive electrode sheet for an organic battery according to an embodiment of the present invention comprises mixing 45-70 wt% of the electrochemically active molecule of a sulfur-containing heterocyclic triptycenequinone, 20-45 wt% of a conductive additive, and 5-10 wt% of a binder in a solvent, coating the mixture on a current collector, pre-drying the mixture in a blast oven at 80°C for 5 hours, cutting the mixture into discs, and then drying the mixture in a vacuum oven at 100°C for 24 hours to obtain the positive electrode sheet. The conductive agent is not limited to carbon nanotubes, conductive carbon black, acetylene black, etc., the binder is not limited to polyvinylidene fluoride, polytetrafluoroethylene, etc., the solvent is N-methylpyrrolidone, and the current collector includes aluminum foil, carbon-coated aluminum foil, carbon felt, etc.

[0052] An organic lithium metal battery according to an embodiment of the present invention is assembled from the triptycenequinone organic positive electrode sheet containing sulfur heterocycles, the lithium metal negative electrode sheet, and a suitable separator and electrolyte. In some embodiments, the separator is a glass fiber separator, a polypropylene separator, etc., and the electrolyte is a 1 mol / L lithium trifluoromethanesulfonic acid imide dissolved in a mixed solvent of 1,3-dioxolane and 1,2-dimethoxyethane in a volume ratio of 1:1.

[0053] Embodiment 1:

[0054] The preparation of a sulfur-containing heterocyclic triptycenequinone active material comprises the following steps:

[0055] Weigh 60 mg of 2,3,6,7,14,15-hexachlorotriptenequinone and 160 mg of sodium sulfide nonahydrate, transfer them to a Shrek tube, add 20 mL of N,N-dimethylformamide, freeze / vacuum three times to remove oxygen in the solution, react at 75°C for 3 hours, the solution color turns dark green, and after cooling, add 100 mg of 2,3-dichloro-1,4-naphthoquinone, freeze / vacuum three times to remove oxygen in the solution, stir and heat at 100°C for 48 hours to obtain a brown reaction mixture, evaporate the organic solvent in the brown reaction mixture, wash with 200 mL each of deionized water, ethanol, and tetrahydrofuran in turn, and dry in a vacuum oven at 100°C to obtain the sulfur-containing heterocyclic triptenequinone active material, liquid phase nuclear magnetic resonance 1 H spectrum Figure 2 As shown, solid-state nuclear magnetic 13 C spectrum Figure 3 As shown, the mass spectrum Figure 4 As shown, the infrared absorption spectrum is Figure 5 Scanning electron microscope images are shown in Figure 6 shown.

[0056] Embodiment 2:

[0057] The preparation of a sulfur-containing heterocyclic triptycenequinone active material comprises the following steps:

[0058] 60 mg of 2,3,6,7,14,15-hexachlorotriptylenequinone and 160 mg of sodium sulfide nonahydrate were weighed and transferred to a Shrek tube, 20 mL of N,N-dimethylformamide was added, and the solution was subjected to freeze / vacuum cycles three times to remove oxygen from the solution. The solution was reacted at 90° C. for 3 hours until the color of the solution turned dark green. After cooling, 120 mg of 2,3-dichloro-1,4-anthracenedione was added, and the solution was subjected to freeze / vacuum cycles three times to remove oxygen from the solution. The solution was stirred and heated at 120° C. for 48 hours to obtain a brown reaction mixture. The organic solvent in the brown reaction mixture was evaporated, and the mixture was washed with 200 mL each of water, ethanol, and tetrahydrofuran in sequence and dried in a vacuum oven at 100° C. to obtain the sulfur-containing heterocyclic triptylenequinone active material.

[0059] Embodiment 3:

[0060] The preparation of a sulfur-containing heterocyclic triptycenequinone active material comprises the following steps:

[0061] Weigh 60 mg of 2,3,6,7,14,15-hexachlorotriptylenequinone and 160 mg of sodium sulfide nonahydrate, transfer them to a Shrek tube, add 20 mL of N,N-dimethylformamide, freeze / vacuum three times to remove oxygen in the solution, react at 60° C. for 3 hours, the solution color turns dark green, and after cooling, add 62 mg of 2,3-difluorobenzoquinone, freeze / vacuum three times to remove oxygen in the solution, stir and heat at 100° C. for 48 hours to obtain a brown reaction mixture, evaporate the organic solvent in the brown reaction mixture, wash with 200 mL each of water, ethanol, and tetrahydrofuran in turn, and dry in a vacuum oven at 100° C. to obtain the sulfur-containing heterocyclic triptylenequinone active material.

[0062] Embodiment 4:

[0063] The preparation of a sulfur-containing heterocyclic triptycenequinone active material comprises the following steps:

[0064] 60 mg of 2,3,6,7,14,15-hexachlorotriptylquinone and 160 mg of sodium sulfide nonahydrate were weighed and transferred to a Shrek tube, 20 mL of N,N-dimethylacetamide was added, and the solution was subjected to freeze / vacuum cycles three times to remove oxygen from the solution. The solution was reacted at 80° C. for 3 hours until the color of the solution turned dark green. After cooling, 115 mg of 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione was added, and the solution was subjected to freeze / vacuum cycles three times to remove oxygen from the solution. The solution was stirred and heated at 90° C. for 48 hours to obtain a brown reaction mixture. The organic solvent in the brown reaction mixture was evaporated, and the mixture was washed with 200 mL each of water, ethanol, and tetrahydrofuran in sequence and dried in a vacuum oven at 100° C. to obtain the sulfur-containing heterocyclic triptylquinone active material.

[0065] Embodiment 5:

[0066] The preparation of a sulfur-containing heterocyclic triptycenequinone active material comprises the following steps:

[0067] Weigh 60 mg of 2,3,6,7,14,15-hexachlorotriptylquinone and 160 mg of sodium sulfide nonahydrate, transfer them to a Shrek tube, add 20 mL of N,N-dimethylacetamide, freeze / vacuum three times to remove oxygen in the solution, react at 80° C. for 3 hours, the solution color turns dark green, and after cooling, add 100 mg of 6,7-dichloroquinoxaline-5,8-dione, freeze / vacuum three times to remove oxygen in the solution, stir and heat at 120° C. for 48 hours to obtain a brown reaction mixture, evaporate the organic solvent in the brown reaction mixture, wash with 200 mL each of water, ethanol, and tetrahydrofuran in turn, and dry in a vacuum oven at 100° C. to obtain the sulfur-containing heterocyclic triptylquinone active material.

[0068] Embodiment 6:

[0069] The preparation of a sulfur-containing heterocyclic triptycenequinone positive electrode sheet comprises the following steps:

[0070] According to the mass ratio of 5:4:1, a sulfur-containing heterocyclic triptycenequinone active molecule, conductive carbon black, and polyvinylidene fluoride were ground and mixed uniformly, and an appropriate amount of N-methylpyrrolidone was added dropwise. After the slurry was fully stirred, it was fully mixed and coated on the aluminum foil current collector, and then dried in a blast oven at 80°C for 5 hours, cut into discs with a diameter of 12 mm, and then dried in a vacuum drying oven at 100°C for 24 hours. The loading range of the active material was 0.25-0.5 mg / cm 2 .

[0071] Test example:

[0072] Application and performance test of a sulfur-containing heterocyclic triptycenequinone active cathode in fast-charging organic lithium metal batteries:

[0073] 1) Assembly of lithium metal battery: The positive electrode is the triptycenequinone active material containing sulfur heterocycle prepared by the present invention, the negative electrode is lithium metal, the diaphragm is a polypropylene diaphragm, and the electrolyte is a 1 mol / L solution of 1,3-dioxolane and 1,2-dimethoxyethane of lithium trifluoromethanesulfonamide, wherein the volume ratio of 1,3-dioxolane and 1,2-dimethoxyethane is 1:1. CR2032 button battery is used for assembly, and the structure is positive electrode cover, gasket, positive electrode, electrolyte, diaphragm, electrolyte, lithium metal negative electrode, gasket, spring, negative electrode cover.

[0074] 2) Electrochemical test: At room temperature, the lithium metal battery prepared in Example 1 was subjected to constant current charge and discharge test on a Blue Power CT2001A, with a voltage range of 1.5 to 3.5 V and a current density of 90 mA / g. The charge and discharge curves are as follows: Figure 7 As shown, the maximum specific capacity can reach 288mAh / g, the active sites are fully utilized, and the energy density is 738Wh / kg; the battery is tested for high-rate performance, such as Figure 8 As shown, the voltage range is 1.5 to 3.5 V. At an extremely high rate of 90C (27A / g), the battery is charged for 25 seconds to 65% of the total capacity, with excellent rate performance. The battery is tested for long cycle stability performance, such as Fig. 9 As shown, a 2000-cycle long cycle stability performance test was carried out at a high current density of 15C (4.5A / g), and the battery capacity retention rate was 90.88%, and the coulombic efficiency was stable.

[0075] It can be seen from the above embodiments that the positive electrode plate prepared in the above embodiments of the present invention has very excellent rate performance and long cycle performance through clever molecular structure design, and solves the problems of dissolution of organic positive electrode materials and poor metal ion transmission.

[0076] In summary, the present invention provides a sulfur-containing heterocyclic triptycenequinone organic battery positive electrode material and a preparation method thereof. Tripterycenequinone is used as a precursor, and the flanks of the triptycenequinone molecule are extended, so that the flanks of adjacent molecules can undergo supramolecular self-assembly under strong π-π interactions to form a two-dimensional supramolecular polymer, which is difficult to dissolve in conventional electrolytes, effectively alleviating the dissolution problem of organic positive electrode materials and improving long-cycle stability performance; the van der Waals force between the two-dimensional supramolecular polymer layers is weak, and during the charge and discharge process, the interlayer spacing is easily expanded, so that metal ions can be quickly transmitted through the interlayer to the active site, and redox reactions occur, so while maintaining long-cycle stability performance, it has very excellent rate performance; in addition, the structure has abundant active sites and a higher voltage platform, so it has a higher theoretical capacity and energy density. The ultimate realization of the application of organic positive electrode materials with high energy density, fast charging performance, and long-cycle stability performance is of great practical significance for promoting the development and application of organic batteries.

[0077] The above contents are further detailed descriptions of the present invention in combination with specific / preferred implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. It should be understood that the above descriptions are not used to limit the scope of protection of the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A sulfur-containing heterocyclic triptycenequinone electrochemically active molecule, characterized in that: The invention comprises a propeller-type triptycenequinone formed by extending the side flanks of 2,3,6,7,14,15-hexachlorotriptycenequinone compounds through a thioether bond bridge.

2. The sulfur-containing heterocyclic triptycenequinone electrochemically active molecule according to claim 1, characterized in that: The invention comprises a propeller-shaped triptycenequinone formed by connecting 2,3,6,7,14,15-hexachlorotriptycenequinone with any one of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione through a nucleophilic substitution reaction.

3. A method for preparing a sulfur-containing heterocyclic triptycenequinone electrochemically active molecule, characterized in that: The three reaction substrates are combined by a solvothermal method to obtain a propeller-type triptycenequinone formed by the sulfide bond bridge-type extended flanks of the quinone compound. The three reaction substrates are 2,3,6,7,14,15-hexachlorotriptycenequinone, sodium sulfide nonahydrate and at least one quinone halogen compound that can react with the above two compounds to form a sulfide bond.

4. The method for preparing the electrochemically active molecule of triptycenequinone containing a sulfur heterocycle as claimed in claim 3, wherein the quinone halogen compound is any one of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione.

5. The method for preparing the electrochemically active molecule of triptycenequinone containing sulfur heterocycle according to claim 3, characterized in that: The steps include: Step 1): 2,3,6,7,14,15-hexachlorotriptylenquinone, sodium sulfide nonahydrate and an organic solvent are added to a reaction container, and the oxygen in the solution is removed by freezing / vacuuming for three times, and the reaction is carried out at a temperature of 60 to 90° C. for 1 to 3 hours to obtain a dark green reaction mixture; Step 2): adding any one of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione monomers to the mixed solution, freezing / vacuuming for three times to remove oxygen from the solution, and continuing to react at a temperature of 90 to 120° C. for 36 to 64 hours to obtain a brown reaction mixture; Step 3): The organic solvent in the brown reaction mixture is evaporated, and the obtained solid is washed with deionized water, ethanol, and tetrahydrofuran in sequence and dried to obtain the target triptycenequinone compound.

6. The method for preparing the electrochemically active molecule of triptycenequinone containing sulfur heterocycle according to claim 5, characterized in that: In step 1), the organic solvent is any one of dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide, and the quantitative molar ratio of the 2,3,6,7,14,15-hexachlorotriptylenquinone to the sodium sulfide nonahydrate is 1:6 to 1:6.

5.

7. The method for preparing the electrochemically active molecule of triptycenequinone containing sulfur heterocycle according to claim 5, characterized in that: In step 2), the quantitative molar ratio of the monomer addition amount of 2,3-difluorobenzoquinone, 2,3-dichloronaphthoquinone, 2,3-dichloroanthraquinone, 6,7-dichloroquinoxaline-5,8-dione and 2,3-dichloro-5,8-dihydroxynaphthalene-1,4-dione to 2,3,6,7,14,15-hexachlorotriptycenequinone is 4:1 to 5:

1.

8. A positive electrode sheet, characterized in that: The method comprises 45-70 wt % of the sulfur-containing heterocyclic triptycenequinone electrochemically active molecule according to any one of claims 1 to 2, 20-45 wt % of a conductive additive and 5-10 wt % of a binder.

9. An organic metal battery, characterized in that: It comprises the positive electrode as claimed in claim 8, a metal negative electrode, a separator and an electrolyte.

10. The organic battery according to claim 9, characterized in that: The metal negative electrode is any one of lithium metal, zinc metal and sodium metal; the electrolyte is lithium bis(trifluoromethanesulfonyl)imide dissolved in a mixed solvent of 1,3-dioxolane and 1,2-dimethoxyethane.

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