A high-voltage high-specific-energy long-life organic battery device

Abstract

The application provides a high-voltage high-specific-energy long-service-life organic battery device, and belongs to the technical field of battery devices.The high-voltage high-specific-energy long-service-life organic battery device provided by the application comprises a positive electrode, a negative electrode, a diaphragm and an electrolyte, the positive electrode is composed of a current collector, an active material, a conductive agent and a binder, the active material has a structure shown in formula 1, and G is a group with an electron-donating effect; the electrolyte is a fluorinated ester electrolyte; by selecting the positive electrode active material, the electrolyte and the negative electrode, the specific capacity and the energy density of the battery device can be improved, and the cycle performance and the service life of the battery device can be significantly improved.

Description

Technical Field

[0001] This invention relates to the field of battery device technology, and in particular to a high-voltage, high-energy-density, long-life organic battery device. Background Technology

[0002] Lithium-ion batteries have been widely used in electric vehicles and portable electronic devices due to their high energy density, excellent specific capacity, and good cycle stability. However, existing commercial lithium-ion battery systems mainly rely on transition metal-based inorganic electrode materials, which are limited in resource distribution and have continuously rising costs. At the same time, the preparation and recycling of these materials are usually accompanied by high energy consumption and may cause environmental problems such as heavy metal pollution, making it difficult to meet the urgent needs of future energy storage technologies for sustainability and greening.

[0003] Against this backdrop, organic battery systems built around organic molecules are gradually becoming an important development direction for next-generation electrochemical energy storage systems due to their advantages such as wide availability of raw materials, relatively mild synthesis processes, strong structural designability, and environmental friendliness. From the perspective of energy storage mechanisms, organic electrode materials can be mainly divided into three categories: n-type, p-type, and bipolar. While n-type materials typically offer higher specific capacity, their low operating potential (<2.5 V vs. Li / Li+) limits the improvement of the overall energy density of the device. In contrast, p-type materials possess higher redox potentials, which are more conducive to achieving high voltage output, but their energy storage process largely relies on single-electron transfer mechanisms, resulting in capacity limitations and making it difficult to simultaneously achieve high energy density and high voltage characteristics.

[0004] In recent years, many multi-electron p-type organic compounds have been reported to have the potential to achieve high energy densities. These p-type organic compounds possess multiple active sites, enabling multi-electron transfer and thus high capacity output at high voltages. However, when applying these multi-electron p-type organic cathode active materials to organic battery devices, if metal-based anodes (especially lithium metal anodes) are used, a series of technical bottlenecks still need to be addressed at the practical battery device level: On the one hand, the high-oxidation-state species of these multi-electron p-type organic active materials are highly unstable, prone to rearrangement, coupling, disproportionation, and other side reactions, and may further react with electrolyte solvent molecules. These processes lead to a significant decline in the redox reversibility of the electrode and rapid consumption of the electrolyte and active materials, thus severely affecting the battery's capacity and cycle life. On the other hand, the negative electrode (such as metallic lithium) is prone to uncontrolled lithium dendrite growth during charge-discharge cycles, which may not only penetrate the separator and cause short circuits, but also intertwine with the interfacial stability issues of the polymer material on the positive electrode side under high voltage, resulting in simultaneous instability of the positive and negative electrode interfaces, making it difficult to guarantee the cycle stability, lifespan, and safety of the battery device. In addition, there are issues such as voltage window matching between the high-voltage positive electrode and the metal-based negative electrode, compatibility of the electrolyte at different potentials, and side reactions of the polymer positive electrode in the high-voltage region. Therefore, from the process of positive electrode material to battery device assembly, how to ensure the stable performance of the high specific energy of the positive electrode material in the battery, while taking into account the compatibility of the positive and negative electrodes and the electrolyte, and improving the cycle stability and lifespan of the battery device, has become the main problem to be solved in this study. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a high-voltage, high-specific-energy, long-life organic battery device. The organic battery device provided by the present invention improves the specific capacity and energy density of the battery device by selecting positive electrode active material, electrolyte and negative electrode, thereby significantly improving cycle performance and life.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: A high-voltage, high-energy-density, long-life organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The active material has the structure shown in Formula 1. Formula 1, The G is a group with an electron-donating effect; the electrolyte is a fluorinated ester electrolyte.

[0007] Preferably, X1 and X2 are independently selected from any one of S, O, NR, or O=S=O.

[0008] Preferably, when X1 and X2 are independently selected as NR, R is any one of H, alkyl, alkoxy or aryl; The alkyl group is any one of methyl, ethyl and isopropyl; The alkoxy group is methaneoxy and / or ethaneoxy; The aryl group is any one of phenyl, tolyl, and aniline.

[0009] Preferably, G is any one or more of alkyl, alkoxy, and amino groups; The alkyl group is any one or more selected from methyl, ethyl and isopropyl; The alkoxy group is methaneoxy and / or ethaneoxy; The amino group is any one of primary amino group, aniline group, and triphenylamine.

[0010] Preferably, the active material has any one of the structures shown in Formulas 2-5. Equation 2, Formula 3, Equation 4, Formula 5.

[0011] Preferably, the conductive agent includes one or more of Ketjen Black, acetylene black, SuperP, and carbon nanotubes.

[0012] Preferably, the adhesive comprises one or more of polytetrafluoroethylene, polyvinylidene fluoride, sodium carboxymethyl cellulose, styrene-butadiene rubber, and sodium alginate.

[0013] Preferably, the fluorinated ester electrolyte comprises a fluorinated solvent and a lithium salt; the fluorinated solvent comprises a fluorinated ester solvent and / or, wherein the fluorinated ester solvent comprises one or more of fluoroethylene carbonate, methyl trifluoroethyl carbonate, methyl difluoroacetate, ethyl difluoroacetate, ethyl trifluoroacetate, and methyl trifluoroacetate.

[0014] Preferably, the fluorinated solvent includes fluoroethylene carbonate and / or methyltrifluoroethyl carbonate.

[0015] Preferably, the negative electrode comprises a lithium metal or lithium alloy negative electrode.

[0016] Beneficial effects: The organic battery device provided by this invention uses a positive electrode made of a dibenzohexane aromatic six-membered ring organic active material. Leveraging the inherent multi-electron transfer mechanism of the organic structure, it can achieve continuous multi-step single-electron redox processes at high potentials, thereby significantly improving the reversible capacity of the positive electrode material. Thanks to the precise control of the electronic structure by the electron-donating group G in the active material's structural formula, the positive electrode material exhibits superior reversibility and electrochemical stability in its multi-step redox reactions at high potentials, effectively suppressing the adverse effects of intermediates and side reactions. This invention combines a multi-electron positive electrode material with a high-capacity, low-potential lithium metal-based negative electrode material to form a battery device, achieving high energy density synergistically at the battery device level. Simultaneously, the use of a fluorinated ester electrolyte, with its high oxidation resistance and metal anode compatibility, effectively constructs a stable positive / negative electrode interface, solving the problem of interfacial side reactions under high-voltage operation, thus ensuring the stable release of the high specific capacity of the positive electrode material and giving the device excellent cycle life. Attached Figure Description

[0017] Figure 1 The organic battery device of Example 1 of the present invention operates at 1.5 mVs. -1 Cyclic voltammetry curves at scan rate.

[0018] Figure 2 This is the charge-discharge curve of the organic battery device in Example 1 of the present invention.

[0019] Figure 3 This is a graph showing the energy density and power density of the organic battery device in Embodiment 1 of the present invention.

[0020] Figure 4 The organic battery device of Example 1 of the present invention is in 10Ag -1 Cyclic performance diagram at current density.

[0021] Figure 5 The organic battery device containing a diphenyl heterocyclic aromatic six-membered ring phenothiazine positive electrode active material used in Comparative Example 1 of this invention operates at 1Ag -1 The charge-discharge curves at current density.

[0022] Figure 6 The organic battery device containing a diphenyl heterocyclic aromatic six-membered ring phenothiazine positive electrode active material used in Comparative Example 1 of this invention was tested at 2Ag. -1 Cyclic performance diagram at current density.

[0023] Figure 7 The organic battery device containing a single-electron triphenylamine positive electrode active material used in Comparative Example 2 of this invention operates at 1Ag... -1 The charge-discharge curves at current density.

[0024] Figure 8 This is a rate performance diagram of the organic battery device of Comparative Example 6 of the present invention.

[0025] Figure 9 The organic battery device of Comparative Example 6 of this invention was tested at 5Ag. -1 The following is a graph showing the cyclic performance.

[0026] Figure 10 This is a comparison chart of the energy density of Embodiment 1 and Comparative Examples 1-7 of the present invention. Detailed Implementation

[0027] This invention provides a high-voltage, high-energy-density, long-life organic battery device, comprising a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The active material has the structure shown in Formula 1. Formula 1, The G group is a group with an electron-donating effect, and the electrolyte is a fluorinated ester electrolyte.

[0028] In this invention, the organic battery device includes a positive electrode, which is composed of a current collector, an active material, a conductive agent, and a binder; in this invention, the mass ratio of the active material, the conductive agent, and the binder is preferably 5~10:1~5:1~3.

[0029] In this invention, the active material, conductive agent, and binder are mixed and then attached to the surface of the current collector in the form of a film. The shape of the current collector is not particularly required in this invention, but in the embodiments it is preferably circular or rectangular. The size of the current collector is preferably 1mm~20mm × 1mm~20mm or a diameter of 1mm~20mm. In this invention, the material of the current collector is preferably carbon material or metallic material. The carbon material includes any one of carbon cloth, carbon mesh, and carbon sheet. The metallic material is preferably any one of titanium, copper, aluminum, and nickel. In the embodiments of this invention, carbon cloth or titanium mesh is further preferred.

[0030] In this invention, the active material has the structure shown in Formula 1, wherein X1 and X2 are independently selected from any one of S, O, NR or O=S=O; in this invention, the X1 and X2 groups can be the same or different. When X1 and X2 are independently selected as NR, R is one or more of H, alkyl, alkoxy, or aryl, more preferably methyl; in this invention, the alkyl is preferably any one of methyl, ethyl, and isopropyl, more preferably hydrogen or methyl; in this invention, the alkoxy is preferably methaneoxy and / or ethaneoxy, more preferably methaneoxy; in this invention, the aryl is any one of phenyl, tolyl, and aniline, more preferably phenyl.

[0031] In this invention, a further preferred embodiment of the active material is that X1 is NR and X2 is S, and the structural formula of the active material is shown in the figure:

[0032] This invention selects an organic compound containing the above-mentioned structural formula as the positive electrode active material. Its inherent multi-electron transfer mechanism allows for continuous multi-step single-electron redox processes at high potentials. Each active site can participate in multiple electron transfers, potentially achieving high capacity output at high voltages and thus high energy density. Simultaneously, the electron-donating group G introduced into the structure precisely regulates the electronic structure of the material, lowers the energy barrier of redox reactions, improves the stability of oxidized species, reduces side reactions, and facilitates multi-step reactions, thereby improving charge transport kinetics, reversible capacity, and cycle stability under high-rate conditions.

[0033] In this invention, the active material has the structure shown in Formula 1, wherein the G group is preferably one or more of alkyl, alkoxy, and amino groups; in this invention, the alkyl group is preferably any one or more of methyl, ethyl, and isopropyl, and more preferably methyl; in this invention, the alkoxy group is preferably methaneoxy and / or ethaneoxy, and more preferably methaneoxy; in this invention, the amino group is preferably any one of primary amino, aniline, and triphenylamine, and more preferably triphenylamine.

[0034] In this invention, the active material preferably has any one of the structures shown in Formulas 2-5. Equation 2, Formula 3, Equation 4, Formula 5.

[0035] In this invention, the positive electrode includes a conductive agent, which includes one or more of Ketjen Black, acetylene black, SuperP, and carbon nanotubes; more preferably, Ketjen Black.

[0036] In this invention, the positive electrode includes a binder, which includes one or more of polytetrafluoroethylene, polyvinylidene fluoride, sodium carboxymethyl cellulose, styrene-butadiene rubber, and sodium alginate, and is more preferably polytetrafluoroethylene.

[0037] In this invention, the organic battery device includes a separator, which includes one or more of polyethylene separator, polypropylene separator and glass fiber separator, and is more preferably a polypropylene separator.

[0038] In this invention, the organic battery device includes an electrolyte, which is a fluorinated ester electrolyte, preferably comprising a fluorinated solvent and a lithium salt; in this invention, the lithium salt may be selected from one or more of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalateborate), lithium difluorooxalateborate, and lithium perchlorate, and is more preferably lithium hexafluorophosphate; in this invention, the lithium concentration in the electrolyte is preferably 1~5 mol / L; In this invention, the fluorinated solvent includes fluorinated carbonates and / or fluorinated carboxylic acid esters. The fluorinated ester solvent includes one or more of fluorinated ethylene carbonate, methyl trifluoroethyl carbonate, methyl difluoroacetate, ethyl difluoroacetate, ethyl trifluoroacetate, and methyl trifluoroacetate, more preferably fluorinated ethylene carbonate and / or methyl trifluoroethyl carbonate. In a specific embodiment of this invention, the fluorinated solvent includes fluorinated ethylene carbonate and methyl trifluoroethyl carbonate in a volume ratio of 1:1. The fluorinated ester electrolyte selected in this invention possesses high oxidation resistance and compatibility with metal anodes, effectively constructing a stable positive / negative electrode interface, solving the problem of interfacial side reactions under high voltage operation, thereby ensuring the stable release of the high specific capacity of the positive electrode material and endowing the device with excellent cycle life. The fluorinated ester electrolyte selected in this invention does not produce severe side reactions on the lithium metal anode compared to other electrolytes, exhibits good compatibility, and is chemically inert to high-voltage organic cathode materials. This avoids the problem of conventional carbonate or ether electrolytes decomposing and producing gas at high potentials. The electron-donating group G in the cathode material further reduces the reactivity between the cathode material and the electrolyte, suppressing side reactions such as irreversible rearrangement of multi-electron organic cathodes under high voltage, as well as parasitic reactions with the electrolyte solvent.

[0039] In this invention, the organic battery device includes a negative electrode, which includes a lithium metal and a lithium alloy negative electrode.

[0040] This invention also provides a method for preparing the above-mentioned organic battery device, comprising the following steps: The positive electrode active material, conductive agent and binder are mixed and then laid on the surface of the current collector to form a film; The current collector after film formation is dried to obtain the positive electrode sheet; The positive electrode, electrolyte, and negative electrode are assembled in a glove box to obtain an organic battery device.

[0041] In this invention, there is no particular limitation on the mixing order of the positive electrode active material, conductive agent and binder, as long as they can be mixed evenly; there is no particular limitation on the mixing method; the mixing in this invention is preferably carried out in anhydrous ethanol to obtain a mixed slurry, and the mixed slurry is ground and dried before being laid on the surface of the current collector to form a film.

[0042] In this invention, the film is preferably formed by rolling it into a film using a roller press under a pressure of 0.2~1 MPa, and the film thickness is preferably 10~120 μm.

[0043] In this invention, the drying is preferably carried out under vacuum conditions, the drying temperature is preferably 80~120℃, and the drying time is preferably 12~24h; in this invention, the vacuum degree is ≤ -0.1 MPa.

[0044] In this invention, the organic battery device is preferably a button cell or a pouch cell. The button cell also includes positive and negative electrode shells and spring pads. The pouch cell also includes an aluminum-plastic film shell, which is disposed on the outermost shell of the battery to form a sealed cavity that completely encloses the organic battery device.

[0045] In this invention, the assembly process of the button battery in the glove box specifically includes the following steps: Place the negative electrode shell with the opening facing upwards, and place the spring and gasket in the center in sequence; Place the negative electrode in the center of the pad to ensure close contact; After adding electrolyte to the surface of the negative electrode to completely wet it, place the diaphragm in the center of the negative electrode and ensure that the diaphragm completely covers the negative electrode. Add electrolyte again until the diaphragm is fully wetted. Place the positive electrode in the center of the separator, with the positive electrode active material layer facing the separator; Finally, place the positive electrode shell, fasten it, and place it in a sealing machine for sealing and compaction to obtain the organic battery device.

[0046] In this invention, the amount of electrolyte added can be adjusted according to the areal density of the positive electrode active material and the membrane size, preferably 50 to 200 μL.

[0047] In this invention, the sealing and compaction pressure is preferably 0.8 to 1.2 MPa, and the pressure holding time is preferably 3 to 10 seconds.

[0048] In this invention, the assembly process is preferably carried out in an inert atmosphere; the inert gas is preferably helium, neon or argon; in this invention, the glove box has a water content of less than 0.1 ppm and an oxygen content of less than 0.1 ppm.

[0049] To further illustrate the present invention, the organic battery device provided by the present invention will be described in detail below with reference to examples, but these examples should not be construed as limiting the scope of protection of the present invention.

[0050] Example 1

[0051] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The molecular structure of the positive electrode active material is shown below:

[0052] Using the organic polymer as the positive electrode active material, Ketjen black as the conductive agent, polytetrafluoroethylene as the binder, and titanium mesh as the positive electrode current collector, the positive electrode active material, conductive agent, and binder were uniformly mixed in 5 ml of isopropanol solvent at a mass ratio of 6:3:1. The mixture was then uniformly spread on a circular titanium mesh with a diameter of 10 mm, rolled into a film, and dried in a vacuum environment at 100°C for 20 h to obtain an organic positive electrode sheet.

[0053] Battery device assembly: Select lithium metal anode, polypropylene separator, and fluorinated ester electrolyte. The electrolyte composition is 1 M (mol / L) LiPF6 dissolved in a 1:1 volume ratio of fluoroethylene carbonate (FEC) / methyl trifluoroethyl carbonate (FEMC) mixed solvent. Assemble the battery in a glove box according to the coin cell method to obtain an organic battery device.

[0054] Figure 1 The organic battery device of Example 1 at 1.5 mVs -1 Cyclic voltammetry curves at scan rate.

[0055] Figure 2 The charge-discharge curves for the organic battery device of Example 1 are shown; this organic battery can output 3.7 V vs. Li. + / Li has a high potential at 0.5Ag -1 It can output 185 mAh g at a current density. -1 High specific capacity, at 15Ag -1 It can still maintain 82 mAh g at a current density. -1 Its high specific capacity demonstrates excellent rate performance.

[0056] Figure 3 The graph shows the energy density and power density of the organic battery device in Example 1. As can be seen from the graph, this organic battery can provide 684.5 Wh / kg. -1 The high energy density of this organic battery device, while maintaining 243 Wh / kg -1 While maintaining high energy density, it can output 49 kW kg -1 The power density is [not specified]. Based on the total mass of the positive and negative electrode active materials (N / P=8), it can still output 495 Wh / kg. -1 Energy density.

[0057] Figure 4Example 1: Organic battery device at 10Ag -1 The cycling performance diagram at the current density shows that the organic battery device can cycle stably for more than 3100 cycles with 83% capacity retention, demonstrating excellent cycling stability.

[0058] Example 2

[0059] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The molecular structure of the positive electrode active material is shown below:

[0060] Using the organic polymer as the positive electrode active material, acetylene black as the conductive agent, polyvinylidene fluoride as the binder, and carbon cloth as the positive electrode current collector, the positive electrode active material, conductive agent, and binder were uniformly mixed in 5 ml of N-methylpyrrolidone solvent at a mass ratio of 8:1:1. The mixture was then uniformly spread on a circular carbon cloth with a diameter of 10 mm, rolled into a film, and dried in a vacuum environment at 100℃ for 15 h to obtain an organic positive electrode sheet.

[0061] Battery device assembly: Select lithium metal anode, polypropylene separator, and fluorinated ester electrolyte. The electrolyte composition is 1 M (mol / L) LiPF6 dissolved in a 1:1 volume ratio of fluoroethylene carbonate (FEC) / methyl trifluoroethyl carbonate (FEMC) mixed solvent. Assemble the battery in a glove box according to the coin cell method to obtain an organic battery device.

[0062] Example 3

[0063] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The molecular structure of the positive electrode active material is shown below:

[0064] Using the organic polymer as the positive electrode active material, acetylene black as the conductive agent, polyvinylidene fluoride as the binder, and aluminum foil as the positive electrode current collector, the positive electrode active material, conductive agent, and binder were uniformly mixed in 5 ml of N-methylpyrrolidone solvent at a mass ratio of 7:2:1. The mixture was then uniformly spread on a circular aluminum foil with a diameter of 10 mm, rolled into a film, and dried in a vacuum environment at 100℃ for 20 h to obtain an organic positive electrode sheet.

[0065] Battery device assembly: Select lithium metal anode, polypropylene separator, and fluorinated ester electrolyte. The electrolyte composition is 1 M (mol / L) LiPF6 dissolved in a 1:1 volume ratio of fluoroethylene carbonate (FEC) / methyl trifluoroethyl carbonate (FEMC) mixed solvent. Assemble the battery in a glove box according to the coin cell method to obtain an organic battery device.

[0066] Example 4

[0067] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The molecular structure of the positive electrode active material is shown below:

[0068] Using the organic polymer as the positive electrode active material, Super P as the conductive agent, polyvinylidene fluoride as the binder, and aluminum foil as the positive electrode current collector, the positive electrode active material, conductive agent, and binder were uniformly mixed in 5 ml of N-methylpyrrolidone solvent at a mass ratio of 8:1:1. The mixture was then uniformly spread on a circular aluminum foil with a diameter of 10 mm, rolled into a film, and dried in a vacuum environment at 120°C for 12 h to obtain an organic positive electrode sheet.

[0069] Battery device assembly: Select lithium metal anode, polypropylene separator, and fluorinated ester electrolyte. The electrolyte composition is 1 M (mol / L) LiPF6 dissolved in a 1:1 volume ratio of fluoroethylene carbonate (FEC) / methyl trifluoroethyl carbonate (FEMC) mixed solvent. Assemble the battery in a glove box according to the coin cell method to obtain an organic battery device.

[0070] Comparative Example 1

[0071] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The molecular structure of the positive electrode active material is shown below:

[0072] Using the organic polymer as the positive electrode active material, Ketjen black as the conductive agent, polytetrafluoroethylene as the binder, and titanium mesh as the positive electrode current collector, the positive electrode active material, conductive agent, and binder were uniformly mixed in 5 ml of isopropanol solvent at a mass ratio of 6:3:1. The mixture was then uniformly spread on a circular titanium mesh with a diameter of 10 mm, rolled into a film, and dried in a vacuum environment at 100°C for 20 h to obtain an organic positive electrode sheet.

[0073] Battery device assembly: Select lithium metal anode, polypropylene separator, and fluorinated ester electrolyte. The electrolyte composition is 1 M (mol / L) LiPF6 dissolved in a 1:1 volume ratio of fluoroethylene carbonate (FEC) / methyl trifluoroethyl carbonate (FEMC) mixed solvent. Assemble the battery in a glove box according to the coin cell method to obtain an organic battery device.

[0074] Figure 5 The organic battery device containing a diphenyl heterocyclic aromatic six-membered ring phenothiazine positive electrode active material used in Comparative Example 1 of this invention was tested at 0.5 Ag. -1 The charge-discharge curves for the first three cycles at the given current density.

[0075] Figure 6 The organic battery device containing a diphenyl heterocyclic aromatic six-membered ring phenothiazine positive electrode active material used in Comparative Example 1 of this invention was tested at 2Ag. -1 Cyclic performance diagram at current density.

[0076] The battery device in Comparative Example 1 is basically the same as that in Example 1, except that the positive electrode active material in Comparative Example 1 is not modified with electron-donating substituents. Because no electron-donating groups are introduced, phenothiazine is prone to side reactions such as deprotonation and free radical coupling, making the second redox process difficult to proceed reversibly. Therefore, the capacity is not fully utilized, reaching only 102 mAh g. -1 Furthermore, it exhibits poor cycle stability and low coulombic efficiency, with a capacity retention rate of only 30% after 250 cycles.

[0077] Comparative Example 2

[0078] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The rest of the battery device is the same as in Example 1, except that the molecular structure of the positive electrode active material is shown below: .

[0079] Figure 7 The organic battery device containing a single-electron triphenylamine positive electrode active material used in Comparative Example 2 of this invention operates at 1Ag... -1 The charge-discharge curves at current density.

[0080] Comparative Example 2 has a basically the same battery device structure as Example 1, except that the positive electrode active material in Comparative Example 2 contains only one active site, allowing only single-electron transfer and resulting in a lower capacity of 1 A g. -1 At a current density, the capacity is only 74 mAh g. -1 The output energy density is only 259 Wh kg. -1 (Based on the mass calculation of the positive electrode active material).

[0081] Comparative Example 3

[0082] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The battery device design is the same as in Example 1, except that the positive electrode active material is selected as a lithium iron phosphate positive electrode material.

[0083] Comparative Example 4

[0084] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The rest of the battery device is the same as in Example 1, except that the positive electrode active material is selected as a lithium cobalt oxide positive electrode material.

[0085] Comparative Example 5

[0086] An organic battery device includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The rest of the battery device is the same as in Example 1, except that the positive electrode active material is selected as lithium nickel cobalt manganese oxide (NCM523).

[0087] Comparative Example 6

[0088] The difference between Comparative Example 6 and Example 1 is that a non-fluorinated ether electrolyte is used, with the electrolyte composition being 1 M LiTFSI dissolved in a 1:1 volume ratio of 1,3-dioxolane (DOL) / ethylene glycol dimethyl ether (DME) mixed solvent; the rest of the scheme is the same as in Example 1.

[0089] Figure 8 The scaling performance diagram is for Comparative Example 6; Figure 9 Comparative Example 6 at 5Ag -1 The following is a graph showing the cycle performance; via Figure 8 and Figure 9 Analysis shows that due to the poor oxidative stability of LiTFSI electrolyte and the easy dissolution of this positive electrode active material in ether-based electrolytes during charge and discharge, the battery device exhibits low capacity and poor rate performance, particularly at 0.5 Ag. -1 It can only output 92 mAh g at a current density. -1 The specific capacity at 15Ag -1 It can only output 33mAh g at a current density. -1 The specific capacity was high; at the same time, the comparative battery device showed poor cycle stability, with a capacity retention of only 60% after 500 cycles.

[0090] Comparative Example 7

[0091] The difference between Comparative Example 7 and Example 1 is that graphite is used instead of lithium metal as the negative electrode material. The graphite in Comparative Example 7 has a higher potential than lithium metal (approximately 0.05-0.2 V vs. Li). + / Li) and its capacity is much lower than that of lithium metal (only 372 mAhg). -1 Therefore, the assembled battery device exhibits a low energy density of only 390 Wh kg. -1 (Calculated based on the total mass of the positive and negative electrode active materials).

[0092] Figure 10 This is a comparison chart of the energy density of Embodiment 1 and Comparative Examples 1-7 of the present invention. Figure 10 Analysis shows that the organic battery device assembled in Example 1 of the present invention has the highest energy density (calculated based on the total mass of the positive and negative electrode active materials).

[0093] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles 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 high-voltage, high-energy-density, long-life organic battery device, characterized in that, It includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode is composed of a current collector, an active material, a conductive agent, and a binder. The active material has the structure shown in Formula 1. Formula 1, The G is a group with an electron-donating effect; the electrolyte is a fluorinated ester electrolyte.

2. The organic battery device according to claim 1, characterized in that, X1 and X2 are independently selected from any one of S, O, NR, or O=S=O.

3. The organic battery device according to claim 1, characterized in that, When X1 and X2 are independently selected as NR, R is any one of H, alkyl, alkoxy or aryl; The alkyl group is any one of methyl, ethyl and isopropyl; The alkoxy group is methaneoxy and / or ethaneoxy; The aryl group is any one of phenyl, tolyl, and aniline.

4. The organic battery device according to claim 1, characterized in that, G is any one or more of alkyl, alkoxy, and amino groups; The alkyl group is any one or more selected from methyl, ethyl and isopropyl; The alkoxy group is methaneoxy and / or ethaneoxy; The amino group is any one of primary amino group, aniline group, and triphenylamine.

5. The organic battery device according to claim 1, characterized in that, The active material has any one of the structures shown in Formulas 2-5. Equation 2, Formula 3, Equation 4, Formula 5.

6. The organic battery device according to claim 1, characterized in that, The conductive agent includes one or more of Ketjen Black, acetylene black, SuperP, and carbon nanotubes.

7. The organic battery device according to claim 1, characterized in that, The adhesive includes one or more of polytetrafluoroethylene, polyvinylidene fluoride, sodium carboxymethyl cellulose, styrene-butadiene rubber, and sodium alginate.

8. The organic battery device according to claim 1, characterized in that, The fluorinated ester electrolyte includes a fluorinated solvent and a lithium salt; the fluorinated solvent includes fluorinated ester solvents and / or one or more of fluoroethylene carbonate, methyl trifluoroethyl carbonate, methyl difluoroacetate, ethyl difluoroacetate, ethyl trifluoroacetate, and methyl trifluoroacetate.

9. The organic battery device according to claim 8, characterized in that, The fluorinated solvents include fluoroethylene carbonate and / or methyltrifluoroethyl carbonate.

10. The organic battery device according to claim 1, characterized in that, The negative electrode includes lithium metal and lithium alloy negative electrodes.

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