Preparation of polyarylether quinone type organic positive electrode material and application of polyarylether quinone type organic positive electrode material in lithium ion battery

Abstract

The invention discloses a polyarylether quinone type organic positive electrode material, a preparation method thereof and application of the polyarylether quinone type organic positive electrode material to a lithium ion battery, and belongs to the field of lithium ion battery materials. Aiming at the problems of limited resources, capacity bottleneck, strong solubility of small organic molecule positive electrodes and poor cycling stability of the existing inorganic positive electrode materials, the invention designs a series of polyarylether quinone polymers with a structure as shown in a formula (I), and the polyarylether quinone polymers are embedded into benzoquinone redox active groups through a rigid conjugated skeleton to realize high-performance energy storage. And meanwhile, the material can realize compatibility of a wet process and a dry process, has the potential of realizing industrialization, and provides support for development of the organic positive electrode material.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of lithium ion batteries, and particularly relates to a preparation of a polyaromatic ether quinone type organic positive electrode material and application thereof in lithium ion batteries. BACKGROUND

[0002] As the core of modern energy storage technology, lithium ion batteries are widely used in consumer electronics, electric vehicles and renewable energy storage due to their high energy density and long cycle life. Currently, commercial lithium ion batteries mainly rely on inorganic positive electrode materials (such as lithium cobaltate, ternary materials and lithium iron phosphate), which realize charge storage through the redox reaction of transition metal ions. However, inorganic materials have significant drawbacks: first, the limited reserves and uneven distribution of key metals such as cobalt and nickel lead to high costs and supply chain risks; second, metal mining and battery recycling processes can easily cause environmental pollution problems; third, the theoretical capacity of inorganic materials has approached the ceiling (such as lithium cobaltate, only about 140 mAh / g), and at high voltage, it is easy to cause structural collapse or electrolyte decomposition, resulting in decreased cycle life and safety hazards. These problems have prompted researchers to turn to resource-rich and environmentally friendly new positive electrode material systems.

[0003] In recent years, organic small molecule positive electrode materials have attracted attention due to their renewable resources, strong designability of molecular structure and high theoretical capacity. They realize lithium ion storage through reversible redox reactions in organic molecules (such as electron transfer of C=O double bond), and the theoretical capacity of some materials can reach more than 300 mAh / g. However, small molecule materials are easily dissolved in electrolyte, leading to active material loss and rapid capacity decay; at the same time, their low conductivity requires a high proportion of conductive additives, reducing the energy density of the battery. In addition, small molecules are prone to irreversible structural rearrangement during charging and discharging, further limiting the cycle stability. To overcome these defects, researchers have proposed introducing active groups into the polymer backbone to construct organic polymer positive electrode materials. The long-chain structure of the polymer can effectively inhibit dissolution and enhance structural stability, and the conjugation effect can improve electronic conductivity, providing a new direction for the development of high-performance positive electrode materials.

[0004] Organic polymers containing benzoquinone structures (such as polybenzoquinone and polyimide derivatives) are currently a hot research topic. The benzoquinone group possesses high redox activity and reversible lithium-ion insertion / extraction capabilities, endowing materials with high specific capacity (typically exceeding 200 mAh / g). By embedding benzoquinone units into the rigid polymer backbone, the dissolution of active groups can be significantly suppressed, and the three-dimensional network structure can buffer volume changes, improving cycle performance. Furthermore, the conjugated structure of the polymer backbone enhances electron transport capabilities and reduces dependence on conductive agents. Flexible molecular-level design also allows for the manipulation of voltage plateaus and lithium-ion diffusion pathways, for example, by introducing electron-withdrawing groups to increase oxidation potential or constructing porous structures to accelerate ion migration. These materials combine high capacity, long lifetime, and low environmental impact, promising a revolutionary solution for next-generation low-cost, sustainable lithium-ion batteries.

[0005] In addition, regarding electrode manufacturing processes, traditional lithium-ion battery electrode manufacturing mainly relies on wet coating processes. This process requires dissolving active materials, conductive agents, and binders (such as PVDF) in organic solvents such as N-methylpyrrolidone (NMP) to form a slurry, which is then coated onto the current collector and baked at high temperatures to remove the solvent. However, wet processes have significant drawbacks: NMP is reproductively toxic, posing a threat to worker health and the environment, and its use and disposal are strictly limited; at the same time, establishing and operating large-scale solvent recovery systems (such as distillation columns) is costly, and the solvent evaporation and drying process is energy-intensive and inefficient. To overcome these limitations, dry electrode processes, especially the polytetrafluoroethylene (PTFE) fiberization method, have emerged. This technology abandons the use of solvents, mixing a small amount (about 2-5%) of the original fiberized binder PTFE powder with the active material, and using strong shearing to stretch the PTFE particles into fine mesh fibers, which wrap around the active particles like a "nano-spider web," forming a self-supporting electrode film, which is then hot-pressed and composited with the current collector. The core advantage of the dry process (PTFE fiberization) lies in the complete elimination of harmful solvents and their associated health and environmental risks and recycling costs, which significantly reduces energy consumption (by about 40%), simplifies the process and improves production efficiency. Furthermore, due to the higher proportion of active materials and the excellent stability of PTFE, it has the potential to improve electrode performance and safety, and is leading lithium battery manufacturing towards a more environmentally friendly, economical and efficient direction. Summary of the Invention

[0006] To address the aforementioned problems, the present invention aims to provide a polyarylene ether quinone type polymer cathode material with high specific capacity, resistance to dissolution, excellent thermal stability, and compatibility with dry / wet electrode processes, as well as a method for its preparation.

[0007] The polyarylene ether quinone type polymer for lithium-ion battery electrode active materials of the present invention comprises repeating units of the structure shown in formula (I):

[0008]

[0009] n is a positive integer representing the degree of aggregation;

[0010] X is (X1) or does not exist;

[0011] -O-

[0012] (X1)

[0013] Y is selected from (Y1) to (Y4) or does not exist;

[0014]

[0015] Molecular weight range: number average molecular weight 15-150kDa, weight average molecular weight 30-300kDa, dispersion index 1.3-3.

[0016] Furthermore, in the embodiments provided by the present invention, the polyarylene ether quinone polymer is one or more of the P1 to P5 structures:

[0017]

[0018]

[0019] Furthermore, the polyarylene ether quinone polymer used as an active material for lithium-ion batteries preferably has a number-average molecular weight of 15-150 kDa, a weight-average molecular weight of 30-300 kDa, and a dispersion index (the ratio of weight-average molecular weight to number-average molecular weight) of 1.3-3.

[0020] Furthermore, the present invention provides a method for preparing a polyarylene ether quinone type polymer for use as an active material in lithium-ion batteries, the steps of which are as follows:

[0021] Step 1: Add the nucleophilic substitution reagent, the monomer compound of formula (I) and 18-crown ether-6 to the reaction solvent in sequence, start stirring, and purge the protective gas in a closed system for half an hour.

[0022]

[0023] Step 2: Begin heating, slowly increasing the temperature. After 50 minutes, the system temperature will reach 120℃. Maintain this temperature for approximately 3 hours to remove water, keeping the temperature between 120-125℃. After water removal is complete, gradually increase the temperature to 180℃ and continue the reaction for approximately 20 hours, during which the reaction solution will gradually become viscous.

[0024] Step 3: Discharge the reaction solution obtained in Step 2 into deionized water. A precipitate will form. Let it stand for 8 hours to allow the precipitation to complete. Wash the product three times with distilled water, then three times with ethanol, and extract with ethyl acetate, tetrahydrofuran, and chloroform, respectively. Finally, dry the product in a vacuum oven at 80°C for six hours to obtain the final product, with the structural formula shown in Formula (III).

[0025]

[0026] Furthermore, the reaction solvent in step one is preferably a high-boiling-point solvent, such as dimethyl sulfoxide, N,N-dimethylformamide, N-methylpyrrolidone, and sulfolane; the molar ratio of the prepolymer monomer (I) and the nucleophilic substitution reagent is 1:(0.8-2.2); the amount of additive is 0.2% to 5% of the mass of the monomer of formula (I);

[0027] Furthermore, in step one, the ventilation is carried out under a protective gas (such as nitrogen, argon, etc.).

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] First, the polyarylene ether quinone polymer for lithium-ion battery active materials provided by this invention has a simple, efficient, and direct synthesis method, namely, obtaining the product through a one-step nucleophilic condensation reaction and a coupling reaction under mild reaction conditions. At the same time, the reaction raw materials are readily available and reasonably priced.

[0030] Secondly, the polyarylene ether quinone type polymer for lithium-ion battery active materials provided by this invention has strong structural designability, and can achieve goals such as improving specific capacity and improving solubility in electrolyte through reasonable structural design.

[0031] Third, the polyarylene ether quinone polymer designed and synthesized in this invention produces batteries with high discharge specific capacity and good cycle performance (specific capacity >120mAh / g, capacity retention rate >65% after 100 cycles) when prepared under both wet and dry electrode processes. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0033] Figure 1 The present invention proposes a general structural formula for a polyarylene quinone-type organic cathode material. Figures 2-6Infrared spectra of polymers in Examples 1-5.

[0034] Figures 7-9 Thermogravimetric curves of Examples 1-5;

[0035] Figures 10-19 Battery cycle performance diagrams for Examples 11-20.

[0036] right Figures 10-19 Additional notes: The test voltage range is 1.2V-3.5V, with a multiplier of 0.1C. Detailed Implementation

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] For clarity, the following examples will be used to provide a detailed description.

[0039] Example 1: Preparation of a polyarylene ether quinone type organic polymer (P1)

[0040] In a fixed three-necked flask, 4,4'-difluorobenzophenone, 2,5-dihydroxy-1,4-benzoquinone, and dried potassium carbonate were added sequentially, with argon gas continuously introduced and stirring constantly. Sulfolane was added and stirred at low speed, followed by the addition of 18-crown ether-6, and 10 mL of toluene was added as a dehydrating agent. The stirring speed was increased and the mixture was heated to 120°C to begin dehydration. After dehydration was complete, the temperature was gradually increased to approximately 190°C to continue the reaction. When the system reached a certain viscosity, stirring was stopped, the apparatus was disassembled, and the hot product was discharged into 1000 mL of deionized water. After standing and washing, the final product was obtained.

[0041] Example 2: Preparation of a polyarylene ether quinone type organic polymer (P2)

[0042] In a fixed three-necked flask, 4,4′-difluorodiphenyl sulfone, 2,5-dihydroxy-1,4-benzoquinone, and dried potassium carbonate were added sequentially, with argon gas continuously introduced and stirring constantly. Sulfolane was added and stirred at low speed, followed by the addition of 18-crown ether-6, and 10 mL of toluene was added as a dehydrating agent. The stirring speed was increased and the mixture was heated to 120°C to begin dehydration. After dehydration was complete, the temperature was gradually increased to approximately 190°C to continue the reaction. When the system reached a certain viscosity, stirring was stopped, the apparatus was disassembled, and the hot product was discharged into 1000 mL of deionized water. After standing and washing, the final product was obtained.

[0043] Example 3: Preparation of a polyarylene ether quinone type organic polymer (P3)

[0044] In a fixed three-necked flask, 1,5-dichloroanthraquinone, 2,5-dihydroxy-1,4-benzoquinone, and dried potassium carbonate were added sequentially, with argon gas continuously introduced and stirring constantly. Sulfolane was added and stirred at low speed, followed by the addition of 18-crown ether-6, and 10 mL of toluene was added as a dehydrating agent. The stirring speed was increased and the mixture was heated to 120 °C to begin dehydration. After dehydration was complete, the temperature was gradually increased to approximately 190 °C to continue the reaction. When the system reached a certain viscosity, stirring was stopped, the apparatus was disassembled, and the hot product was discharged into 1000 mL of deionized water. After standing and washing, the final product was obtained.

[0045] Example 4: Preparation of a polyarylene ether quinone type organic polymer (P4)

[0046] In a fixed three-necked flask, 2,5-difluoro-1,4-benzoquinone, 2,5-dihydroxy-1,4-benzoquinone, and dried potassium carbonate were added sequentially, with argon gas continuously introduced and stirring constantly. Sulfolane was added and stirred at low speed, followed by the addition of 18-crown ether-6, and 10 mL of toluene was added as a dehydrating agent. The stirring speed was increased and the mixture was heated to 120°C to begin dehydration. After dehydration was complete, the temperature was gradually increased to approximately 190°C to continue the reaction. When the system reached a certain viscosity, stirring was stopped, the apparatus was disassembled, and the hot product was discharged into 1000 mL of deionized water. After standing and washing, the final product was obtained.

[0047] Example 5: Preparation of a polyarylene ether quinone type organic polymer (P5)

[0048] In a fixed three-necked flask, 2,5-dichloro-1,4-benzoquinone, 2,2'-bipyridine, and dried potassium carbonate were added sequentially, with argon gas continuously introduced and stirring constantly. Dimethyl sulfoxide was added and stirred at low speed, with 5 mL of toluene added as a dehydrating agent. The stirring speed was increased and the mixture was heated to 170°C and maintained for two hours. The temperature was then gradually decreased to approximately 80°C to continue the reaction. Bis(1,5-cyclooctadiene)nickel was added, and the temperature was maintained at 80°C for five hours. When the system reached a certain viscosity, stirring was stopped, the apparatus was disassembled, and the product was discharged hot into methanol. After standing and washing, the final product was obtained.

[0049] Example 6: Application of polyarylene ether quinone type organic cathode materials in wet process lithium-ion batteries

[0050] Using 50% P1 as the active material, it was mixed and ground with 40% Ketjen Black (a conductive agent) and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIin DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0051] Example 7: Application of polyarylene ether quinone type organic cathode material in wet process lithium-ion batteries

[0052] Using 50% P2 as the active material, it was mixed and ground with 40% Ketjen Black (a conductive agent) and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIin DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0053] Example 8: Application of polyarylene ether quinone type organic cathode material in wet process lithium-ion batteries

[0054] Using 50% P3 as the active material, it was mixed and ground with 40% Ketjen Black (a conductive agent) and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIinDOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0055] Example 9: Application of polyarylene ether quinone type organic cathode material in wet process lithium-ion batteries

[0056] Using 50% P4 as the active material, it was mixed and ground with 40% Ketjen Black (a conductive agent) and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIinDOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0057] Example 10: Application of polyarylene ether quinone type organic cathode materials in wet process lithium-ion batteries

[0058] Using 50% P5 as the active material, it was mixed and ground with 40% Ketjen Black (a conductive agent) and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIin DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0059] Example 11: Application of polyarylene ether quinone type organic cathode materials in wet process lithium-ion batteries

[0060] Using 50% P1 as the active material, it was mixed and ground with 40% SuperP conductive agent and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIin DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0061] Example 12: Application of polyarylene ether quinone type organic cathode material in wet process lithium-ion batteries

[0062] Using 50% P2 as the active material, it was mixed and ground with 40% SuperP conductive agent and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIin DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0063] Example 13: Application of polyarylene ether quinone type organic cathode materials in wet process lithium-ion batteries

[0064] Using 50% P3 as the active material, it was mixed and ground with 40% SuperP conductive agent and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIinDOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0065] Example 14: Application of polyarylene ether quinone type organic cathode materials in wet process lithium-ion batteries

[0066] Using 50% P4 as the active material, it was mixed and ground with 40% SuperP conductive agent and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIinDOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0067] Example 15: Application of polyarylene ether quinone type organic cathode materials in wet process lithium-ion batteries

[0068] Using 50% P5 as the active material, it was mixed and ground with 40% SuperP conductive agent and 10% PVDF polymer binder at room temperature for 0.5 h to form a uniform powder mixture. An appropriate amount of NMP was added, and grinding continued until an electrode slurry was formed. An aluminum current collector was placed on a glass plate, and the electrode slurry was uniformly coated onto the current collector using a four-sided coater to a thickness of approximately 50 μm. The electrode sheet was dried in a vacuum oven for 12 hours, then mixed at 20 °C for 20 min to form a granular coating. The resulting granular coating was calendered at 100 °C to form a continuous positive electrode self-supporting film with a thickness of 100 μm. A battery was assembled using 1.0 M LiTFSIin DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the counter electrode.

[0069] Example 16: Application of polyarylene ether quinone type organic cathode materials in dry process lithium-ion batteries

[0070] Using 95% P1 as the active material, it was mixed with 3% CNTs as conductive agents at room temperature for 1 hour. Then, 2% PTFE polymer binder was added and mixed at -10℃ for 2 hours to prepare a multi-component mixture with no binder deformation. This mixture was then mixed at 20℃ for 30 minutes to form granular coatings. The resulting granular coatings were calendered at 100℃ to form a continuous positive electrode self-supporting film with a thickness of 50 μm. A battery was assembled using 1M LiPF6 in DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the negative electrode.

[0071] Example 17: Application of polyarylene ether quinone type organic cathode materials in dry process lithium-ion batteries

[0072] Using 95% P2 as the active material, it was mixed with 3% CNTs as conductive agent at room temperature for 1 hour. Then, 2% PTFE polymer binder was added and mixed at -10℃ for 2 hours to prepare a multi-component mixture with no binder deformation. This mixture was then mixed at 20℃ for 30 minutes to form granular coatings. The resulting granular coatings were calendered at 100℃ to form a continuous positive electrode self-supporting film with a thickness of 50 μm. A battery was assembled using 1M LiPF6 in DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the negative electrode.

[0073] Example 18: Application of polyarylene ether quinone type organic cathode materials in dry process lithium-ion batteries

[0074] Using 95% P3 as the active material, it was mixed with 3% CNTs as conductive agents at room temperature for 1 hour. Then, 2% PTFE polymer binder was added and mixed at -10℃ for 2 hours to prepare a multi-component mixture with no binder deformation. This mixture was then mixed at 20℃ for 30 minutes to form granular coatings. The resulting granular coatings were calendered at 100℃ to form a continuous positive electrode self-supporting film with a thickness of 50 μm. A battery was assembled using 1M LiPF6 in DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the negative electrode.

[0075] Example 19: Application of polyarylene ether quinone type organic cathode materials in dry process lithium-ion batteries

[0076] Using 95% P4 as the active material, it was mixed with 3% CNTs as a conductive agent at room temperature for 1 hour. Then, 2% PTFE polymer binder was added and mixed at -10℃ for 2 hours to prepare a multi-component mixture with no binder deformation. This mixture was then mixed at 20℃ for 30 minutes to form granular coatings. The resulting granular coatings were calendered at 100℃ to form a continuous positive electrode self-supporting film with a thickness of 50 μm. A battery was assembled using 1M LiPF6 in DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the negative electrode.

[0077] Example 20: Application of polyarylene ether quinone type organic cathode material in lithium-ion batteries produced by the in-situ process.

[0078] Using 95% P5 as the active material, it was mixed with 3% CNTs as a conductive agent at room temperature for 1 hour. Then, 2% PTFE polymer binder was added and mixed at -10℃ for 2 hours to prepare a multi-component mixture with no binder deformation. This mixture was then mixed at 20℃ for 30 minutes to form granular coatings. The resulting granular coatings were calendered at 100℃ to form a continuous positive electrode self-supporting film with a thickness of 50 μm. A battery was assembled using 1M LiPF6 in DOL:DME (1:1, v / v) as the electrolyte, Celgard 2500 as the separator, and a metallic Li sheet as the negative electrode.

[0079] Solubility test

[0080] The solubility of polymers P1-P5 obtained in Examples 1 to 5 was tested, and the results are shown in Table 1:

[0081] Table 1: Solubility Test Data

[0082]

[0083] 10 mg of polymer dissolved in 1 mL of solvent

[0084] ++ indicates that it dissolves at room temperature; + indicates that it dissolves after heating; - indicates that it does not dissolve after heating.

[0085] Solubility tests show that the polyarylene ether quinone polymer synthesized in this invention exhibits good solubility in conventional polar solvents, water, and electrolyte solvents.

[0086] The above demonstrates that the polyarylene ether quinone polymer designed in this invention can exhibit sufficiently high discharge specific capacity, good cycle performance and conductivity, while also exhibiting high thermal stability and excellent solvent resistance. It can be applied to positive electrode active materials for lithium-ion batteries and is suitable for both wet and dry processes.

[0087] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A polyarylene ether quinone type organic cathode material, characterized in that, The general structural formula of this organic cathode material is: Where n is a positive integer, representing the degree of aggregation; X may represent the structure shown in (X1), or it may not represent any structure: -O- (X1) When X is (X1), Y is one of the structures shown in (Y1) to (Y4): When X does not represent any structure, the possible structures of Y are one of the structures shown in (Y1) to (Y4), or it does not represent any structure:

2. The polyarylene quinone type organic cathode material according to claim 1, characterized in that, The preparation method includes the following steps: 2,5-Dihydroxy-1,4-benzoquinone and reactant A were dissolved in reaction solvent B and heated to carry out a nucleophilic condensation reaction. After the reaction was completed and cooled, the mixture was filtered to obtain a filter cake. The filter cake was washed with a washing solvent and then dried to obtain an organic cathode material.

3. The method for preparing a polyarylene ether quinone type organic cathode material according to claim 2, characterized in that, This method is specific Includes the following steps: 2,5-Dihydroxy-1,4-benzoquinone and reactant A are dissolved in 10 mL to 50 mL of reaction solvent B at a 1:1 equivalent ratio. The mixture is then subjected to water removal at 120 °C for 2 to 6 hours. After water removal is complete, the temperature is gradually increased and the reaction continues for 24 to 30 hours. The reaction is then stopped, and the product is discharged into water and filtered to obtain a filter cake. The filter cake is washed with a washing solvent and then dried to obtain the organic cathode material.

4. The method for preparing a polyarylene ether quinone type organic cathode material according to claim 3, characterized in that, The reactant A is one of 4,4'-difluorobenzophenone, 4,4'-difluorodiphenyl sulfone, 1,5-dichloroanthraquinone, and 2,5-dichloro-1,4-benzoquinone.

5. The method for preparing a polyarylene ether quinone type organic cathode material according to claim 3, characterized in that, The reaction solvent B is one of dimethyl sulfoxide, N-methylpyrrolidone, sulfolane, n-butanol, N,N-dimethylformamide, or tetrahydrofuran.

6. The method for preparing a polyarylene ether quinone type organic cathode material according to claim 3, characterized in that, The inert gas is nitrogen, helium, or argon.

7. The method for preparing a polyarylene ether quinone type organic cathode material according to claim 3, characterized in that, The washing solvent is one or more of methanol, ethanol, isopropanol, n-butanol, ethyl acetate, tetrahydrofuran, dichloromethane, chloroform, N,N-dimethylformamide, N-methylpyrrolidone, 1,3-dioxolane, ethylene glycol dimethyl ether, ethylene carbonate, methyl ethyl carbonate, and deionized water.

8. An application of the polyarylene quinone type organic cathode material as described in claim 1, characterized in that, The polymer can be used to prepare cathode materials for lithium-ion batteries.

9. An application of the polyarylene quinone type organic cathode material as described in claim 1, characterized in that, The polymer can be successfully used to prepare batteries using a dry electrode process and exhibits corresponding electrochemical performance.

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