Zinc-organic secondary battery electrode and zinc-organic secondary battery

Abstract

The invention relates to a zinc-organic secondary battery electrode and a zinc-organic secondary battery. The secondary battery electrode is prepared by the following steps: mixing an organic active material, a conductive agent and a binder to prepare slurry, coating the slurry on a current collector, and drying and tabletting, the organic active material is a thioether structure polymer rich in C = O active functional groups, or a planar phenazine polymer rich in C = O and C = N double active functional groups, or a cyclohexanehexone-based phenazine macromolecule rich in C = O or C = N active functional groups. Compared with the prior art, the zinc secondary battery positive electrode provided by the invention has the advantages of high reversible specific capacity, high discharge voltage, high rate capability, long cycle life, adjustable and designable functional groups and the like.

Description

Technical Field

[0001] This invention belongs to the field of secondary zinc-ion battery technology, and relates to a zinc-organic secondary battery electrode and its preparation, and a zinc-organic secondary battery. Background Technology

[0002] Rechargeable zinc-ion batteries (RZIBs) are advantageous due to the abundance and low cost of zinc metal, as well as their high theoretical capacity (820 mAh g⁻¹). −1 and 5855 mAh cm −3 Zinc-based inorganic batteries (ZIBs) are ideal for large-scale energy storage due to their low redox potential (-0.76 V relative to the standard hydrogen electrode). However, the application of ZIBs still faces significant challenges, including: 1. a lack of high-performance cathode materials; and 2. short cycle life of the zinc anode, resulting in a limited overall battery life. Currently, ZIBs typically use transition metal-based composites (manganese, cobalt, molybdenum, and vanadium-based compounds) and Prussian blue analogues (PBAs) as cathodes, showing some zinc storage capacity, but still limited by the scarcity of mineral resources. More importantly, these inorganic materials are mostly crystalline, and Zn... 2+ The insertion and extraction of zinc electrodes requires overcoming strong chemical bonds (covalent, ionic, and metallic), which makes their rigid structures prone to change. Electrode materials are susceptible to structural collapse and dissolution, severely reducing the battery's cycle life. On the other hand, aqueous electrolytes have been consistently used in the development of zinc batteries. Because zinc metal is thermodynamically unstable in water, the zinc anode faces severe challenges such as dendrite formation, interfacial side reactions, and self-corrosion leading to hydrogen evolution. These problems collectively cause corrosion of the zinc anode, rapid electrolyte consumption, and battery short circuits, thus affecting the overall cycle life of the battery.

[0003] Organic cathode materials contain no metals and can be synthesized indefinitely without consuming resources. During charge and discharge, the redox reactions of organic cathode materials involve only the chemical adsorption and desorption of ions, without altering the structure and valence bonds of the organic cathode material, thus enabling zinc-organic positive batteries to achieve high charge and discharge rates. Furthermore, organic electrode materials possess excellent structural designability; their electrochemical characteristics, including specific capacity, conductivity, and voltage, can be adjusted by modifying the structure of organic molecules. Simultaneously, to overcome key challenges in zinc anodes, particularly eliminating zinc dendrites and enhancing interfacial stability to improve the cycle life of zinc-ion batteries, adapting to thermodynamically stable non-aqueous (organic) electrolytes is crucial.

[0004] For example, Chinese patent CN111081971B provides a method for preparing electrodes for aqueous zinc-ion batteries. It uses the organic material 2,3-diaminophenazine as the active center for electrochemical redox reactions. The electrode sheet is prepared by mixing and grinding it with a conductive agent and binder, adding a dispersant and current collector, and then coating it to ensure the stability of the material structure during charging and discharging. However, the electrode material in this patent still has room for improvement in terms of capacity and solubility in organic electrolytes. Summary of the Invention

[0005] The purpose of this invention is to provide a zinc-organic secondary battery electrode and its preparation, as well as a zinc-organic secondary battery. The provided zinc secondary battery cathode exhibits high reversible specific capacity, discharge voltage, rate performance, and long cycle life. Furthermore, the functional groups are tunable and designable.

[0006] The objective of this invention can be achieved through the following technical solutions: In a first aspect, the present invention provides a zinc-organic secondary battery electrode, which is formed by mixing organic active materials, conductive agents and binders to form a slurry, coating it onto a current collector, and then drying and pressing it into a sheet. The organic active materials are thioether structure polymers rich in C=O active functional groups, or planar phenazine polymers rich in both C=O and C=N active functional groups, or phenazine macromolecules based on cyclohexanehexanone rich in C=O or C=N active functional groups.

[0007] Furthermore, the thioether-structured polymer rich in C=O active functional groups is prepared by the following process: Using one or more of 2,3,5,6-tetrafluoro-1,4-benzoquinone, 2,3,5,6-tetrachloro-1,4-benzoquinone, and 2,3,5,6-tetrabromo-1,4-benzoquinone as the first organic raw material, a portion of the first organic raw material is added to a mixed solvent of ethanol and water, followed by the addition of sodium sulfide. The mixture is heated to reflux, and then a DMF solution containing the remaining portion of the first organic raw material is added. The reaction is continued under reflux. The resulting reaction product is separated, washed, and dried to obtain a sulfide-structured polymer. By using a two-step addition process and considering the different solubilities of the organic raw materials in different solvents, the reaction rate is controlled, the polymer structure is optimized, side reactions are reduced, and the product yield is increased.

[0008] Furthermore, the molar ratio of the first organic raw material to sodium sulfide is 1:(1.5~2.5). The temperatures for reflux heating and continued reflux heating are independently 70~90℃.

[0009] Alternatively, one or more of 2,3,5,6-tetrafluorohydroquinone, 2,3,5,6-tetrachlorohydroquinone, and 2,3,5,6-tetrabromohydroquinone can be used as organic raw materials to obtain a thioether polymer product rich in -OH active functional groups using the above method. After a charge-discharge process (electrochemical oxidation), the -OH groups are oxidized, thereby transforming the above-mentioned thioether polymer rich in C=O active functional groups. That is, this process occurs automatically during normal cycling (at any current density, and the conversion rate increases with the number of cycles).

[0010] Furthermore, the planar phenazine polymer rich in C=O and C=N dual active functional groups is prepared by the following process: One or more of 2,3,7,8-phenazinetetramine, 2,3,5,6-tetra(amino)-p-benzoquinone, 2,7-diaminopyrene-4,5,9,10-tetraone, 2,7-dinitropyrene-4,5,9,10-tetraone, and 2,7-hydroxypyrene-4,5,9,10-tetraone were added as a second organic raw material to a reactor containing acetic acid and reacted under an inert atmosphere. The resulting reaction product was filtered, washed, purified, and dried to obtain a planar phenazine polymer.

[0011] Furthermore, the molar ratio of the second organic raw material to acetic acid is (0.8~1) mmol: 25 mL; The reaction temperature is 110~130℃, and the time is 8~12h.

[0012] Furthermore, the phenazine macromolecules based on cyclohexanehexanone, rich in C=O or C=N active functional groups, are prepared by the following process: Using one or more of 3-diaminonaphthalene, 2,3-diaminopiperazine, 2,3-diaminoquinoxaline, 2,3-diaminonaphthalene-1,4-dione, phenylenediamine, 2,3-diaminoquinoxaline, and 2,3-diaminophenazine as a third organic raw material, it is dissolved with cyclohexanehexanone in a mixed solvent of ethanol and glacial acetic acid, stirred and heated to react, the resulting reaction product is centrifuged, washed, and stirred with 30 wt% nitric acid at 140°C for 3 hours, and after separation and drying, phenazine macromolecules are obtained.

[0013] Furthermore, the molar ratio of the third organic raw material, cyclohexanehexanone, is 3:1; The volume ratio of ethanol to glacial acetic acid is 1:1; The stirring and heating reaction was carried out at a temperature of 110~130℃ for 10~14h.

[0014] Furthermore, the mass ratio of the organic active material, conductive agent, and binder is (40-60):(20-40):(10-20). The conductive agent is acetylene black or Super P; The current collector is a titanium foil or a stainless steel mesh; The adhesive is one or a combination of several of the following: sodium carboxymethyl cellulose, styrene-butadiene rubber, polyvinylidene fluoride, and polytetrafluoroethylene.

[0015] In a second aspect, the present invention provides a zinc-organic secondary battery, using metallic zinc as the negative electrode, the zinc-organic secondary battery electrode as described in the first aspect above as the positive electrode, and an organic electrolyte as the electrolyte. The organic electrolyte is composed of an organic solvent, a zinc salt, and a metal ion additive (optional). This system contains only Zn. 2+ As a charge carrier, when using a PE or PP separator, only a tiny amount of electrolyte (30 μl) is needed to ensure stable battery cycling, which is beneficial for improving battery energy density. At the same time, it optimizes the challenges faced by the zinc anode, and significantly improves the battery's cycle life.

[0016] It should be noted that the secondary zinc-ion battery is assembled using existing conventional methods, which is conventional technology in the field and not an innovative point of this invention, and will not be elaborated further here. The main innovative difference of the secondary zinc-ion battery provided by this invention lies in the use of the aforementioned high-performance organic positive electrode, along with an organic electrolyte compatible with both the organic positive electrode and the zinc negative electrode. Specifically, the separator can be made of porous polyethylene, porous polypropylene, porous polyethylene coated with alumina, porous polyethylene coated with silica, porous polypropylene coated with alumina, porous polypropylene coated with silica, or glass fiber; the negative electrode uses pure zinc, or modified or altered zinc metal can be used as the negative electrode.

[0017] Furthermore, the organic solvent is selected from at least one of N-methylformamide, N,N-dimethylformamide solution, N-methylpyrrolidone, trimethyl phosphate, triethyl phosphate, tetrahydrofuran, dioxolane, sulfolane, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol dimethyl propyl ether, and dimethyl sulfoxide. Preferably, the solvent is pure N-methylformamide (NMF), or a mixed solution of N-methylformamide (NMF) and trimethyl phosphate (TMP). For example, when a mixed solution of N-methylformamide (NMF) and trimethyl phosphate (TMP) is used as the solvent, the volume ratio of the two solvents is 1:9 to 9:1, with an optimal ratio of 1:1.

[0018] Furthermore, the zinc salt is selected from one or more of zinc tetrafluoroborate, zinc perchlorate, zinc trifluoromethanesulfonate, zinc bis(trifluoromethanesulfonyl)imide, zinc bis(fluorosulfonyl)imide, zinc acetate, zinc trifluoroacetate, zinc pyrrolidone carboxylate, zinc chloride, and zinc iodide.

[0019] Furthermore, the metal ion additive is selected from one or more of calcium fluoride, antimony fluoride, lead fluoride, tin fluoride, magnesium fluoride, chromium fluoride, antimony chloride, tin chloride, and chromium chloride. Its addition can optimize the zinc anode problem, thereby improving battery performance.

[0020] Furthermore, the concentration of zinc salt in the organic electrolyte is 0.5~1 mol·L⁻¹. −1 The concentration of the metal ion additive is 0.001~0.25 mol·L⁻¹. −1 .

[0021] Addressing key challenges currently faced by zinc-ion batteries, including the lack of high-performance cathode materials and the limited cycle life of zinc anodes, this invention provides several promising organic cathode materials. Specifically, one such material is a thioether-structured polymer organic electrode material (polytetrachlorobenzoquinone, PTClQ), which exhibits high operating voltage, excellent rate performance, and rapid reaction kinetics. Its polymer chain structure, in relation to Zn... 2+ It plays a crucial role in the reversible binding process while maintaining stability in the electrolyte. Furthermore, this invention also develops a class of organic electrolytes and designs the composition of these electrolytes to optimize for the challenges faced by the zinc anode. At room temperature, a zinc-ion battery using PTClQ as the positive electrode exhibits a performance of 100 mAh g⁻¹. −1 The reversible capacity (0.1 A g) −1 ) and long-term cycling stability (83.9%, 2 A g) −1 It exhibits excellent rate performance (2,000 cycles at current density) and the final constructed zinc-organic cathode secondary battery PTClQ||Zn provides an average operating voltage of approximately 1.1 V. At -20°C, it still provides 90 mAh g⁻¹. −1 Stable capacity and 100% capacity retention after 200 cycles (1000 h) (0.05 Ag) −1 ).

[0022] Compared with existing technologies, the polymer-organic electrode material of this invention has a higher operating voltage, a more stable structure, and lower solubility in electrolytes. Simultaneously, the compatibility with organic electrolytes that are compatible with both the organic positive electrode and the zinc negative electrode significantly improves the cycle life of the secondary zinc-ion battery, increases the battery's operating temperature range, and promotes an increase in battery energy density. Attached Figure Description

[0023] Figure 1 This is a flowchart of the preparation process of the polymer organic material PTClQ in Example 1.

[0024] Figure 2This is the preparation route of planar fenazine polymer organic materials PPHZ, PPHQ and PPHNQ based on pyrene-4,5,9,10-tetraone in Example 2.

[0025] Figure 3 This is the preparation route of TBQPH, a phenazine macromolecular organic material based on cyclohexanehexanone, as described in Example 3.

[0026] Figure 4 The charge-discharge curves (current density 0.05~1 A g) of the PTClQ||Zn battery with 0.5 M Zn(CF3SO3)2 / NMF electrolyte in Example 5 at room temperature (25°C) are shown. −1 ).

[0027] Figure 5 The cycling performance (current density of 0.1 A g) of the PTClQ||Zn, 0.5 M Zn(CF3SO3)2 / NMF battery in Example 5 at room temperature (25°C) is shown. −1 ).

[0028] Figure 6 The cycling performance (current density of 1 A g) of the PTClQ||Zn, 0.5 M Zn(CF3SO3)2 / NMF battery in Example 5 at room temperature (25°C) is shown. −1 ).

[0029] Figure 7 The cycling performance (current density of 2 A g) of the PTClQ||Zn, 0.5 M Zn(CF3SO3)2 / NMF battery in Example 5 at room temperature (25°C) is shown. −1 ).

[0030] Figure 8 The cycling performance (current density of 0.05 A g) of the PTClQ||Zn, 0.5 M Zn(CF3SO3)2 / NMF battery in Example 5 at low temperature (-20°C) is shown. −1 After 200 cycles (1000h), the capacity did not decrease.

[0031] Figure 9 The charge-discharge curves (current density 0.05 A g) of the PTClQ||Zn battery with 0.5 M Zn(CF3SO3)2 / NMF electrolyte in Example 5 after 100 cycles at low temperature (-20°C) are shown. −1 ).

[0032] Figure 10This refers to the cycle performance (current density of 1 A g) of the PTClQ||Zn, 0.5 M Zn(CF3SO3)2 / NMF battery in Example 5 at low temperature (-20°C). −1 ).

[0033] Figure 11 The cycling performance (current density of 0.1 A g) of the PPHQ||Zn, 0.5 M Zn(CF3SO3)2 / NMF battery in Example 7 at room temperature (25°C) is shown. −1 ).

[0034] Figure 12 The figures for the PPHQ||Zn and 0.5 M Zn(CF3SO3)2 / NMF battery in Example 7 are charge-discharge curves (current density 0.1 A g) at different cycle numbers at room temperature (25°C). −1 ) Figure 13 The cycling performance (current density of 1 A g) of the PPHQ||Zn, 0.5 M Zn(CF3SO3)2 / NMF battery in Example 7 at room temperature (25°C) is shown. −1 ).

[0035] Figure 14 The cycling performance of the TBQPH||Zn battery with 1 M Zn(ClO4)2 / TMP electrolyte in Example 8 at room temperature (25°C) is shown (current density 0.1C, theoretical capacity 515 mAh g). -1 ).

[0036] Figure 15 The rate performance (theoretical capacity 515 mAh g) of the TBQPH||Zn battery with 1 M Zn(ClO4)2 / TMP electrolyte in Example 8 at room temperature (25°C) is shown. -1 ).

[0037] Figure 16 The cycling performance (current density of 1C) of the TBQPH||Zn battery with 1 M Zn(ClO4)2 / TMP electrolyte in Example 8 at room temperature (25°C). Detailed Implementation

[0038] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0040] As used herein, the terms "and / or," "or / and," and "and / or" encompass any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. It should be noted that when at least three items are connected using at least two conjunctions selected from "and / or," "or / and," and "and / or," it should be understood that, in this application, the technical solution undoubtedly includes solutions connected by "logical AND," and also undoubtedly includes solutions connected by "logical OR."

[0041] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0042] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0043] This document only specifically discloses some numerical ranges. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, just as any upper limit can be combined with any other upper limit to form an unspecified range. Furthermore, each individually disclosed point or single value can itself serve as a lower or upper limit and be combined with any other point or single value or with other lower or upper limits to form an unspecified range.

[0044] Unless otherwise specified, the temperature parameters in this application may be either constant temperature processing or processing within a certain temperature range. The constant temperature processing allows temperature fluctuations within the precision range controlled by the instrument, such as ±5°C, ±4°C, ±3°C, ±2°C, or ±1°C.

[0045] In this document, the term "suitable" as used in phrases such as "suitable combination," "suitable method," and "any suitable method" refers to the ability to implement the technical solution of this application, solve the technical problem of this application, and achieve the expected technical effect of this application.

[0046] In this application, terms such as "further," "even further," and "particularly" are used to describe purposes and indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0047] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0048] In the description of the application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0049] Unless otherwise specified, all preparations and tests described herein took place at 25°C.

[0050] The terms “comprising,” “including,” “containing,” “having,” “comprising,” or other variations thereof are intended to cover non-closed inclusion, and no distinction is made between these terms. The term “comprising” means that other steps and ingredients may be added without affecting the final result. The compositions and methods / processes of the present invention comprise, consist of, and substantially consist of the essential elements and limitations described herein, as well as any additional or optional ingredients, components, steps, or limitations described herein. No distinction is made between the terms “efficacy,” “performance,” “effect,” and “potency” herein.

[0051] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions. Unless otherwise specified, all technical features and optional technical features of this application can be combined to form new technical solutions.

[0052] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, but sequentially is preferred.

[0053] In the following embodiments, unless otherwise specified, the raw materials or processing techniques are conventional commercially available raw materials or conventional processing techniques in the art.

[0054] Example 1 In a 250 mL flask, 40 mL of ethanol and 50 mL of water were added, followed by the addition of 2,3,5,6-tetrachloro-1,4-benzoquinone (1.2294 g, 5 mmol) and sodium sulfide nonahydrate (4.8036 g, 20 mmol), and the mixture was magnetically stirred until fully dissolved. The solution was then refluxed at 80 °C for 3 h to obtain a black solution. Next, 30 mL of N,N-dimethylformamide (DMF) containing 2,3,5,6-tetrachloro-1,4-benzoquinone (1.2294 g, 5 mmol) was added to the system, and the reaction was continued under reflux at 80 °C for 12 h. After cooling to room temperature, the precipitate was separated and washed sequentially with DMF, water, and ethanol, and then dried in a vacuum oven at 60 °C for 24 h to finally obtain a black polymer powder with a sulfide structure (PTClQ). The preparation process is as follows: Figure 1 As shown.

[0055] Example 2 PPHQ, a planar phenazine polymer organic material based on pyrene-4,5,9,10-tetraketone: 0.13 g (0.48 mmol) of pyrene-4,5,9,10-tetraone and 0.0673 g (0.4 mmol) of 2,3,5,6-tetra(amino)-p-benzoquinone were added to a 50 mL two-necked flask containing acetic acid (25 mL). The mixture was reacted at 120°C for 10 h under an argon atmosphere. After cooling to room temperature, the precipitate was collected by filtration and washed repeatedly with acetic acid, acetone, and ethanol, followed by purification in methanol using a Soxhlet extractor. Finally, PPHQ powder was obtained by vacuum drying at 60°C.

[0056] Example 3 TBQPH, a phenazine macromolecule based on cyclohexanehexanone: TBQPH is synthesized through a simple dehydration condensation reaction of cyclohexanehexanone octhydrate and 2,3-diaminonaphthalene-1,4-dione.

[0057] The procedure was as follows: 0.1561 g of hexane octahydrate and 0.2823 g of 2,3-diaminonaphthalene-1,4-dione were dissolved in 20 mL of a mixed solvent of ethanol and glacial acetic acid (volume ratio = 1:1). The mixture was stirred and heated to 120 °C for 12 h. After the reaction was complete, the product was collected by centrifugation with glacial acetic acid, acetone, ethanol, and water, and then stirred with 30 wt% nitric acid at 140 °C for 3 h. Finally, the product was vacuum dried at 80 °C to obtain TBQPH powder.

[0058] Example 4 N-methylformamide (NMF) was selected as the electrolyte solvent, and zinc trifluoromethanesulfonate (Zn(CF3SO3)2) was added to the solvent to prepare a 0.5 M Zn(CF3SO3)2 / NMF electrolyte.

[0059] Example 5 The above-mentioned polymeric organic active material PTClQ, 20% acetylene black, and 20% Super P were thoroughly mixed at a weight ratio of 40%. Then, 20% binder was added and the mixture was thoroughly ground until the slurry was homogeneous and free of particles. The binder consisted of sodium carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR) in a weight ratio of 2:1, with water as the dispersion solvent. The slurry was then uniformly coated onto titanium foil and vacuum dried at 60°C for 12 hours to obtain the PTClQ organic cathode for zinc-ion batteries. The preparation method of PTClQ is as described in Example 1.

[0060] Battery assembly and testing were conducted as follows: a 0.5 M Zn(CF3SO3)2 / NMF electrolyte was prepared, and Whatman GF / D glass fiber was used as the separator. Zinc metal was used as the negative electrode, and a PTClQ organic electrode was used as the positive electrode to assemble the battery, followed by electrochemical performance testing.

[0061] The charge / discharge cutoff voltage is 0.3~1.6 V (vs. Zn). 2+ / Zn), the test temperature is 25℃. Figure 4 It is a PTClQ||Zn battery with a current density starting from 0.05 A g. -1 up to 1 A g -1 The transverse current charge-discharge curves show a clear charge-discharge plateau and exhibit small voltage polarization. A discharge voltage of approximately 1.1V is also observed, higher than most reported organic cathode materials, demonstrating high operating voltage characteristics. Figure 5 To assess the cycle performance of the PTClQ||Zn battery under low current, the test was initially conducted at 0.05 A g. -1 Activation was performed for 10 cycles at a given current density, after which the current density was increased to 0.1 A g. -1 The results showed that the battery still had a capacity of 95 mAh g after 60 cycles. -1 The reversible capacity demonstrates good cycling stability.

[0062] Figure 6 For PTClQ||Zn batteries at 1 A g -1 Long-cycle performance at current density; Figure 7 For PTClQ||Zn batteries at 2 A g -1 Long-term cycling performance at current density. Long-term cycling results show that even when using a highly soluble solvent such as NMF as the electrolyte, the zinc secondary battery with PTClQ organic material as the positive electrode still exhibits excellent cycle life, proving that PTClQ organic material reduces its solubility in the electrolyte through its polymer structure, thereby ensuring the battery has stable long-term cycling performance.

[0063] Figure 8The cycling performance of the PTClQ||Zn battery was measured at -20℃, with a current density of 0.05 A g. -1 The battery still provides 90 mAh g after 200 cycles (approximately 1000 hours). -1 It has reversible capacity, coulomb efficiency close to 100%, and no capacity decay. Figure 9 It corresponds to Figure 8 The constant current charge-discharge curves of the test. Figure 10 The PTClQ||Zn battery operates at -20℃ with a yield of 1 A g. -1 The long-cycle performance measured by current density shows a significant improvement in cycle stability compared to room temperature. The test results fully demonstrate that the use of organic electrolyte improves the battery's wide-temperature performance, especially its low-temperature performance, resulting in a substantial increase in cycle life.

[0064] Comparative Example 1: The majority of the contents are the same as in Example 5, except that the active material PTC1Q is replaced with an equal mass of 2,3-diaminophenazine.

[0065] Comparative Example 2: It is largely the same as Example 5, except that the active material PTC1Q is replaced with an equal mass of pyrene-4,5,9,10-tetraone.

[0066] Comparative Example 3: It is largely the same as Example 5, except that the active material PTClQ is replaced with an equal mass of tetrachlorobenzoquinone.

[0067] Comparative Example 4: It is largely the same as Example 5, except that the active material PTClQ is replaced with an equal mass of 1,4-naphthoquinone.

[0068] Table 1 shows the performance parameters of zinc-organic batteries for Comparative Examples 1-4 (0.1 A g). -1 ) The active material of PTClQ in Example 5 is a polymer with a thioether structure. Its polymer chains effectively mitigate dissolution in the electrolyte, even in highly soluble solvents like NMF, thus exhibiting excellent cycle stability. In contrast, the active materials in Comparative Examples 1-4 are small molecules, making it difficult to suppress their own dissolution in organic electrolytes. Their high solubility leads to severe battery capacity decay. Furthermore, the introduction of the thioether polymer structure modulates the electron cloud distribution of the entire molecule, thereby optimizing its redox potential and resulting in a higher operating voltage.

[0069] Example 6 The process is largely the same as in Example 5, except that 0.05 mol·L⁻¹ is further added to the organic electrolyte. −1 Antimony fluoride. The addition of antimony fluoride additives can effectively improve the reversibility of the zinc anode by optimizing the zinc anode interface, thereby improving the coulombic efficiency of the full cell.

[0070] Table 2 shows the coulombic efficiency comparison of the zinc-organic battery in Example 6. Example 7 The above-mentioned polymeric organic active material PPHQ (40% by weight), acetylene black (20%), and Super P (20%) were thoroughly mixed. Then, 20% binder was added and the mixture was thoroughly ground until the slurry was homogeneous and free of particles. The binder consisted of sodium carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR) in a weight ratio of 2:1, with water as the dispersion solvent. The slurry was then uniformly coated onto titanium foil and vacuum dried at 60°C for 12 hours to obtain the PPHQ organic cathode for zinc-ion batteries. The preparation method of PPHQ is as described in Example 2.

[0071] Battery assembly and testing were conducted as follows: a 0.5 M Zn(CF3SO3)2 / NMF electrolyte was prepared, and Whatman GF / D glass fiber was used as the separator. Zinc metal was used as the negative electrode, and a PPHQ organic electrode was used as the positive electrode to assemble the battery, followed by electrochemical performance testing.

[0072] The charge / discharge cutoff voltage is 0.2-1.6 V (vs. Zn). 2+ / Zn), the test temperature is 25℃. For example Figure 11 As shown, the PPHQ||Zn system still retains 100 mAh g after 500 cycles. -1 Reversible capacity. Figure 12 The charge-discharge curves showed little difference between 200 and 400 cycles, and the PPHQ||Zn system exhibited good performance at 1 A g. -1 It still provides 50.4 mAh g after 2000 cycles at current density. -1 The reversible capacity demonstrates good cycling stability, which also confirms the good stability of this organic material.

[0073] Example 8 The above-mentioned polymeric organic active material TBQPH, 20% acetylene black, and 20% Super P were thoroughly mixed at a weight ratio of 40%. Then, 20% binder was added and the mixture was thoroughly ground until the slurry was uniform and free of particles. The binder consisted of sodium carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR) in a weight ratio of 2:1, and the dispersion solvent was water. The slurry was then uniformly coated onto titanium foil and vacuum dried at 60°C for 12 hours to obtain the TBQPH organic cathode for zinc-ion batteries. The preparation method of TBQPH is as described in Example 3.

[0074] Battery assembly and testing were conducted as follows: a 1 M Zn(ClO4)2 / TMP electrolyte was prepared, with Whatman GF / D glass fiber as the separator. Zinc metal was used as the negative electrode, and a TBQPH organic electrode was used as the positive electrode to assemble the battery, followed by electrochemical performance testing.

[0075] The charge / discharge cutoff voltage is 0.2-1.5 V (vs. Zn). 2+ / Zn), the test temperature is 25℃. For example Figure 14 As shown, the TBQPH||Zn system provides 210 mAh g at a current of 0.1C. -1 It has a high reversible capacity and no significant capacity decay after 200 cycles. Figure 15 The results show that this battery system also exhibits excellent rate performance. For example... Figure 16 As shown, the TBQPH||Zn battery retains 97% of its capacity after 5000 cycles at 1C current, demonstrating excellent cycle stability.

[0076] Example 9 This embodiment is basically the same as embodiment 4, except that the electrolyte solvent in this embodiment is a mixture of trimethyl phosphate (TMP) and N-methylformamide (NMF), and the volume ratio of the two solvents is 1:9, 2:8, 3:7, 1:1, 7:3, 8:2, and 9:1, respectively.

[0077] Example 10 This embodiment is basically the same as embodiment 4, except that in this embodiment, antimony fluoride (SbF3) is added to the electrolyte as a metal ion additive.

[0078] Example 11 This embodiment is basically the same as Embodiment 4, except that the zinc salt in this embodiment is zinc trifluoroacetate (Zn(CF3COO)2). Example 9 This embodiment is basically the same as that of embodiment 4, except that the zinc salt in this embodiment is zinc perchlorate (Zn(ClO4)2).

[0079] Example 12 This embodiment is basically the same as Example 1, except that the raw material used in this embodiment is 2,3,5,6-tetrabromo-1,4-benzoquinone.

[0080] Example 13 This embodiment is basically the same as Example 2, except that the raw material used in this embodiment is 2,7-diaminopyrene-4,5,9,10-tetraone.

[0081] Example 14 This embodiment is basically the same as Embodiment 2, except that the raw material used in this embodiment is 2,7-dinitropyrene-4,5,9,10-tetraone.

[0082] Example 15 This embodiment is basically the same as Embodiment 2, except that the raw material prepared in this embodiment is 2,3,7,8-phenazinetetramine.

[0083] Example 16 This embodiment is basically the same as Example 3, except that the raw material used in this embodiment is 2,3-diaminoquinoxaline.

[0084] Example 17 This embodiment is basically the same as embodiment 5, except that in this embodiment, the ratio of organic active material, acetylene black, Super P and binder is 6:1:1:2.

[0085] Example 18 This embodiment is basically the same as embodiment 5, except that in this embodiment, the binder is polyvinylidene fluoride (PVDF) and the dispersant is N-methylpyrrolidone (NMP).

[0086] Example 19 This embodiment is basically the same as embodiment 5, except that in this embodiment, the separator used to assemble the battery is a polyethylene (PE) separator.

[0087] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A zinc-organic secondary battery electrode, characterized in that, The product is made by mixing organic active materials, conductive agents and binders to form a slurry, coating it onto a current collector, and then drying and pressing it into tablets. The organic active materials are thioether structure polymers rich in C=O active functional groups, planar phenazine polymers rich in both C=O and C=N active functional groups, or phenazine macromolecules based on cyclohexanehexanone rich in C=O or C=N active functional groups.

2. The zinc-organic secondary battery electrode according to claim 1, characterized in that, The thioether-structured polymer rich in C=O active functional groups was prepared by the following process: Using one or more of 2,3,5,6-tetrafluoro-1,4-benzoquinone, 2,3,5,6-tetrachloro-1,4-benzoquinone, and 2,3,5,6-tetrabromo-1,4-benzoquinone as the first organic raw material, a portion of the first organic raw material is added to a mixed solvent of ethanol and water, followed by the addition of sodium sulfide. The mixture is heated under reflux, and then a DMF solution containing the remaining portion of the first organic raw material is added. The mixture is then heated under reflux again. The resulting reaction product is separated, washed, and dried to obtain a sulfide-structured polymer.

3. The zinc-organic secondary battery electrode according to claim 2, characterized in that, The molar ratio of the first organic raw material to sodium sulfide is 1:(1.5~2.5). The temperatures for reflux heating and continued reflux heating are independently 70~90℃.

4. The zinc-organic secondary battery electrode according to claim 1, characterized in that, The planar phenazine polymer rich in C=O and C=N dual active functional groups was prepared by the following process: One or more of 2,3,7,8-phenazinetetramine, 2,3,5,6-tetra(amino)-p-benzoquinone, 2,7-diaminopyrene-4,5,9,10-tetraone, 2,7-dinitropyrene-4,5,9,10-tetraone, and 2,7-hydroxypyrene-4,5,9,10-tetraone were added as a second organic raw material to a reactor containing acetic acid and reacted under an inert atmosphere. The resulting reaction product was filtered, washed, purified, and dried to obtain a planar phenazine polymer.

5. The zinc-organic secondary battery electrode according to claim 4, characterized in that, The molar ratio of the second organic raw material to acetic acid is (0.8~1) mmol: 25 mL; The reaction temperature is 110~130℃, and the time is 8~12h.

6. The zinc-organic secondary battery electrode according to claim 1, characterized in that, The phenazine macromolecules based on cyclohexanehexanone, rich in C=O or C=N active functional groups, are prepared by the following process: Using one or more of 2,3-diaminonaphthalene, 2,3-diaminopiperazine, 2,3-diaminoquinoxaline, 2,3-diaminonaphthalene-1,4-dione, phenylenediamine, 2,3-diaminoquinoxaline, and 2,3-diaminophenazine as a third organic raw material, it is dissolved with cyclohexanehexanone in a mixed solvent of ethanol and glacial acetic acid, stirred and heated to react, the resulting reaction product is centrifuged, washed, and stirred with 30 wt% nitric acid at 140°C for 3 hours, and after separation and drying, phenazine macromolecules are obtained.

7. The zinc-organic secondary battery electrode according to claim 6, characterized in that, The molar ratio of the third organic raw material and cyclohexanehexanone is 3:1; The volume ratio of ethanol to glacial acetic acid is 1:1; The stirring and heating reaction was carried out at a temperature of 110~130℃ for 10~14h.

8. The zinc-organic secondary battery electrode according to claim 1, characterized in that, The mass ratio of the organic active material, conductive agent and binder is (40-60):(20-40):(10-20); The conductive agent is acetylene black or Super P; The current collector is a titanium foil or a stainless steel mesh; The adhesive is one or a combination of several of the following: sodium carboxymethyl cellulose, styrene-butadiene rubber, polyvinylidene fluoride, and polytetrafluoroethylene.

9. A zinc-organic secondary battery, characterized in that, The method uses metallic zinc as the negative electrode, the zinc-organic secondary battery electrode as described in any one of claims 1-8 as the positive electrode, and an organic electrolyte as the electrolyte, wherein the organic electrolyte comprises an organic solvent and a zinc salt.

10. A zinc-organic secondary battery according to claim 9, characterized in that, The organic solvent is selected from at least one of N-methylformamide, N,N-dimethylformamide solution, N-methylpyrrolidone, trimethyl phosphate, triethyl phosphate, tetrahydrofuran, dioxolane, sulfolane, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol dimethyl propyl ether, and dimethyl sulfoxide. The zinc salt is selected from one or more of zinc tetrafluoroborate, zinc perchlorate, zinc trifluoromethanesulfonate, zinc bis(trifluoromethanesulfonyl)imide, zinc bis(fluorosulfonyl)imide, zinc acetate, zinc trifluoroacetate, zinc pyrrolidone carboxylate, zinc chloride, and zinc iodide. The concentration of zinc salt in the organic electrolyte is 0.5~1 mol·L⁻¹ −1 The concentration of the metal ion additive is 0.001~0.25 mol·L⁻¹. −1 .

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