A high-voltage organic electrode material based on an azapentacene derivative and a preparation method and application thereof

Abstract

The application relates to the field of organic electrode materials, and discloses a high-voltage organic electrode material based on an azapentacene derivative as well as a preparation method and application thereof. The application takes a pi-conjugated azaheterocyclic aromatic polymer as an organic electrode material, and higher specific capacity is obtained by reducing the average molecular weight of each active center. In addition, the conjugated extended structure of the azapentacene derivative can reduce the electron density of the nitrogen-oxygen redox active center, further improve the discharge voltage, and meanwhile, the conjugated extended multi-electron redox active center unit can improve the stability of the redox intermediate through charge delocalization on the conjugated skeleton, thereby improving the cycle stability of the electrode material in the charging and discharging process. Therefore, the lithium-sodium ion battery with the p-BPZR positive electrode based on the application has higher voltage, higher specific capacity and energy density, and excellent cycle stability.

Description

Technical Field

[0001] This invention relates to the field of secondary batteries, and in particular to a high-voltage organic electrode material based on azahexanetetrabenzene derivative, its preparation method, and its application. Background Technology

[0002] Increasingly severe air pollution, global warming, and the depletion of fossil fuels are pressing issues that need to be addressed for sustainable social development. These challenges can only be met by adjusting the existing energy structure and increasing the utilization of environmentally friendly renewable energy sources. Solar, wind, and biomass energy can be converted into electricity, but the intermittent and dispersed nature of these renewable energy sources makes them difficult to utilize directly, necessitating the development of efficient energy storage systems. Among these, lithium-ion batteries, due to their high energy density, long cycle life, and high efficiency, have become the primary power source for portable electronic devices, and their applications in electric vehicles and smart grids have attracted widespread commercial and scientific attention. Currently, commercially available lithium-ion battery cathode materials are mainly based on transition metal oxides and phosphates, but both exhibit significant drawbacks. Therefore, designing efficient, environmentally friendly, and renewable novel cathode materials has become particularly important.

[0003] Organic electrode materials composed of elements such as C, H, O, and N are considered a class of energy storage materials with broad application prospects due to their high theoretical specific capacity, low production cost, high safety, high natural abundance, and easy recyclability. More importantly, the diversity of organic material structures allows for the adjustment of their redox properties through structural modification or functionalization. Furthermore, organic electrode materials based on conversion reactions are not limited by factors such as the number, type, or particle size of charge carriers, and can be compatible with various cations or anions, making energy storage more diversified. Currently, research on organic electrode materials mainly focuses on n-type materials, which generally have low discharge potentials and cannot meet the requirements of high energy density and high power density. Therefore, more and more research is focusing on p-type organic electrode materials with high voltage. However, the trade-off between specific capacity and voltage remains one of the biggest obstacles to the development of organic electrode materials with practically high energy density. Therefore, developing metal-ion batteries with high voltage, high specific capacity, high energy density, and good cycle stability is an unavoidable problem for realizing large-scale energy storage. Summary of the Invention

[0004] To address the aforementioned technical problems, the first objective of this invention is to provide a high-voltage organic electrode material based on azahexanete benzene derivatives. This material is a p-type organic electrode material with conjugated multi-electron active centers, which enables metal-ion batteries to have both high specific capacity and high voltage, while also exhibiting high energy density and good cycle stability.

[0005] A high-voltage organic electrode material p-BPZR based on azahexanetetrabenzene derivative has the following general structural formula:

[0006]

[0007] R1, R2, R3, and R4 are selected from one of H, Me, Et, iPr, tBu, OMe, and OEt, respectively.

[0008] Ar selected One of them.

[0009] Preferably, R1, R2, R3, and R4 are all H, and Ar is... One of them.

[0010] The p-type organic cathode material p-BPZR of the present invention is prepared by copolymerizing a azidotetraphenyl derivative (5,12-dihydrobenzo[b]phenazine) with different bridging groups. On the one hand, higher specific capacity is obtained by increasing the number of active centers in the monomer and reducing the average molecular weight of each active center. On the other hand, the charge distribution density of the nitrogen-based conjugated organic redox centers can be diluted by utilizing the extension of the conjugated backbone, further improving the redox potential and discharge voltage of the battery.

[0011] Experiments have shown that the conversion mechanism of the organic cathode material of the present invention is not limited by factors such as the number, type and particle size of charge carriers. When applied to different types of batteries such as lithium-ion batteries and sodium-ion batteries, it can impart high voltage, specific capacity and power density to the battery, while also having good cycle stability.

[0012] The second objective of this invention is to provide a method for preparing a high-voltage organic electrode material p-BPZR based on azapyridine derivatives, comprising the following steps:

[0013] Step (1): Synthesis of 5,12-dihydrobenzo[b]phenazine

[0014] 2,3-Dihydroxynaphthalene and o-phenylenediamine were ground separately and then mixed. The mixture was deoxygenated three times by a freeze-vacuum-melt cycle. The deoxygenated mixture was reacted in a solid phase at 180°C for 30 minutes to obtain a crude product. After cooling to room temperature, the product was ground in a mortar and pestle, and then washed with methanol, acetone, and diethyl ether, respectively. Finally, it was vacuum dried to obtain a pale yellow 5,12-dihydrobenzo[b]phenazine powder.

[0015] Step (2): Synthesis of organic cathode material p-BPZR

[0016] The 5,12-dihydrobenzo[b]phenazine, aromatic compounds and sodium tert-butoxide obtained in step (1) were degassed in anhydrous xylene to obtain solution I; palladium acetate and 2-bicyclohexylphosphine-2',4',6'-triisopropylbiphenyl were degassed in anhydrous xylene to obtain solution II;

[0017] Solution II was added to solution I, and after deoxygenation via three refrigeration pump-thawing cycles, mixture solution III was obtained. Mixture solution III was stirred at 120°C for 24 hours under nitrogen atmosphere and reflux condensation, then heated to 140°C and stirred for 12 hours. Finally, iodobenzene was added for end-capping reaction for 5 hours to obtain crude product. After the crude product was cooled to room temperature, it was filtered and dispersed sequentially in H2O, EtOH, DCM, DMF, THF, a 1:1 volume ratio of EC and DEC mixed solution, and EA using a mortar and ultrasonic method. The mixture was then washed, filtered, and purified. This process was repeated three times, and the product was vacuum dried to obtain the organic cathode material p-BPZR.

[0018] The aromatic compound is One of them, where X is a halogen.

[0019] Preferably, X is bromine.

[0020] Preferably, the molar ratio of 2,3-dihydroxynaphthalene to o-phenylenediamine is 1:1.

[0021] Preferably, the molar ratio of the 5,12-dihydrobenzo[b]phenazine to the aromatic compound is 1:1.

[0022] Preferably, the molar ratio of palladium acetate, 2-bicyclohexylphosphine-2',4',6'-triisopropylbiphenyl and 5,12-dihydrobenzo[b]phenazine is 0.08–0.15:0.16–0.3:1.

[0023] A third objective of this invention is to provide a battery positive electrode comprising the aforementioned high-voltage organic electrode material p-BPZR based on azahexanetetraphenyl derivative, a conductive agent, a binder, and a current collector aluminum foil.

[0024] Preparation of p-BPZR positive electrode: Active material p-BPZR, conductive agent and binder are mixed with solvent N,N-dimethylpyrrolidone (NMP) in a certain mass ratio (6-9:0.5-3:0.5-3) and coated onto positive electrode current collector and dried. After drying, it is cut into electrode sheets of appropriate size to obtain p-BPZR positive electrode sheet.

[0025] The slurry layer thickness of the p-BPZR positive electrode sheet is 50–100 μm.

[0026] The fourth objective of this invention is to provide a metal-ion battery that uses the aforementioned battery positive electrode.

[0027] Preferably, the metal-ion battery includes a lithium-ion battery or a sodium-ion battery, specifically:

[0028] A lithium-ion battery includes a p-BPZR positive electrode, a separator, a negative electrode, and a lithium salt electrolyte. The negative electrode is generally a lithium sheet, and the lithium salt electrolyte is a 0.5-1.5M lithium salt solution prepared by dissolving lithium salts such as LiTFSI and LiPF6 in an organic solvent.

[0029] Sodium-ion batteries consist of a p-BPZR positive electrode, a separator, a negative electrode, and a sodium salt electrolyte. The negative electrode is generally a sodium sheet, and the sodium salt electrolyte is a 0.5–1.5 M sodium salt solution prepared by dissolving sodium salts such as NaClO4 and NaPF6 in an organic solvent.

[0030] The present invention has the following beneficial effects:

[0031] (1) The present invention adopts the structure of multi-electron redox active center, specifically π-conjugated nitrogen heterocyclic aromatic polymer, and obtains higher specific capacity by increasing the number of active centers in monomer and reducing the average molecular weight of each active center.

[0032] (2) The present invention uses azapyroxene derivative (5,12-dihydrobenzo[b]phenazine) as the active center unit, and utilizes the conjugated extended structure to reduce the electron density of the active center by reducing nitrogen oxidation, thereby further improving the discharge voltage of the battery. At the same time, the multi-electron redox active center unit can improve the stability of the redox intermediate by delocalizing the charge on the conjugated framework, thereby improving the cycle stability of the electrode material during the charge and discharge process.

[0033] (3) This invention uses polymer p-BPZR as the organic cathode material, which can reduce the dissolution of small organic molecules in the electrolyte and avoid problems such as internal short circuits and rapid decrease in battery capacity. These are all beneficial for the battery to have higher voltage, specific capacity, energy density and good cycle stability. Attached Figure Description

[0034] Figure 1 This is the synthesis route of the organic cathode material p-BPZ1 in Example 1.

[0035] Figure 2 This is the synthesis route of the organic cathode material p-BPZ2 in Example 2.

[0036] Figure 3 This is the synthesis route of the organic cathode material p-BPZ3 in Example 3.

[0037] Figure 4This is the 1H NMR spectrum of 5,12-dihydrobenzo[b]phenazine obtained in Example 1.

[0038] Figure 5 This is the mass spectrum of 5,12-dihydrobenzo[b]phenazine obtained in Example 1.

[0039] Figure 6 This is the mass spectrum of the organic cathode material obtained in Example 1.

[0040] Figure 7 This is a scanning electron microscope image of the organic cathode material obtained in Example 1.

[0041] Figure 8 This is the powder diffraction XRD pattern of the organic cathode material obtained in Example 1.

[0042] Figure 9 This is a thermogravimetric analysis (TGA) graph of the organic cathode material obtained in Example 1.

[0043] Figure 10 This is a differential scanning calorimetry (DSC) analysis chromatogram of the organic cathode material obtained in Example 1.

[0044] Figure 11 The image shows the charge-discharge curves of a lithium-ion battery using p-BPZ1 as the positive electrode material in Application Example 1 at a 1C rate.

[0045] Figure 12 This is a long-cycle charge-discharge diagram of a lithium-ion battery using p-BPZ1 as the positive electrode material in Application Example 1 at a 1C rate.

[0046] Figure 13 This is a rate cycling diagram of a lithium-ion battery using p-BPZ1 as the positive electrode material in Application Example 1, from 0.5 to 5C.

[0047] Figure 14 This is the charge-discharge curve of the sodium-ion battery using p-BPZ1 as the positive electrode material in Application Example 2 at a 1C rate.

[0048] Figure 15 This is a long-cycle charge-discharge diagram of a sodium-ion battery using p-BPZ1 as the positive electrode material in Application Example 2 at a 1C rate. Detailed Implementation

[0049] The present invention will now be described in detail through examples.

[0050] In a first aspect, the present invention provides a high-voltage organic electrode material p-BPZR based on azahexanetetrabenzene derivatives, with the following general structural formula:

[0051]

[0052] R1, R2, R3, and R4 are each independently selected from one of H, Me, Et, iPr, tBu, OMe, and OEt;

[0053] Ar selected One of them;

[0054] Secondly, the present invention provides a method for preparing the above-mentioned high-voltage organic electrode material p-BPZR based on azapyridine derivatives, the specific steps of which are as follows:

[0055] Step (1): Synthesis of 5,12-dihydrobenzo[b]phenazine

[0056] 37.5 mmol of 2,3-dihydroxynaphthalene and 37.5 mmol of o-phenylenediamine were ground separately and then mixed. The mixture was deoxygenated three times by a freeze-vacuum-melt cycle. The deoxygenated mixture was reacted in a solid phase at 180 °C for 30 minutes to obtain a crude product. After cooling to room temperature, the mixture was ground and then washed with methanol, acetone, and diethyl ether, respectively. Finally, it was dried under vacuum to obtain the product 5,12-dihydrobenzo[b]phenazine.

[0057] Step (2): Synthesis of organic electrode material p-BPZR

[0058] Solution I was prepared by degassing 1.5 mmol of 5,12-dihydrobenzo[b]phenazine, 1.5 mmol of an aromatic compound, and 4.5 mmol of sodium tert-butoxide in anhydrous xylene (25 mL); Solution II was prepared by degassing 0.15 mmol of palladium acetate and 0.3 mmol of 2-bicyclohexylphosphine-2',4',6'-triisopropylbiphenyl in anhydrous xylene (10 mL).

[0059] Solution II was added to solution I, and after deoxygenation through three refrigeration pump-thawing cycles, mixed solution III was obtained. Mixed solution III was stirred at 120°C for 24 hours under nitrogen atmosphere and reflux condensation conditions, then heated to 140°C and stirred for 12 hours. Finally, 0.5 mL of iodobenzene was added to carry out the end-capping reaction for 5 hours, and after cooling to room temperature, the crude product was obtained.

[0060] The crude product was filtered, and then dispersed sequentially in H2O, EtOH, DCM, DMF, THF, EC / DEC (1:1; v:v), and EA using a mortar and ultrasonic process. The mixture was then washed, filtered, and purified. This process was repeated three times, and the product was vacuum dried to obtain the organic electrode material p-BPZR.

[0061] The aromatic compound is One of them, where X is a halogen.

[0062] Thirdly, the present invention provides a battery positive electrode comprising the above-mentioned high-voltage organic electrode material p-BPZR based on azahexanetetraphenyl derivative, a conductive agent, a binder, and a current collector aluminum foil; wherein the mass ratio of the high-voltage organic electrode material p-BPZR based on azahexanetetraphenyl derivative, the conductive agent, and the binder is 6-9:0.5-3:0.5-3.

[0063] Fourthly, the present invention provides a metal-ion battery, including a lithium-ion battery or a sodium-ion battery. The metal-ion battery uses p-BPZR as the positive electrode material. The positive electrode material, Super P, and polyvinylidene fluoride are mixed in anhydrous N-methyl-2-pyrrolidone at a weight ratio of 6:3:1. The mixture is thoroughly stirred in a centrifugal mixer (Thinky ARE-300) for 30 min (10 min × 3) until a uniform slurry is formed. The slurry is then cast onto a 50 μm thick aluminum foil and dried in a vacuum at 65°C for 12 h, and then subjected to a pressure of 10 MPa·cm⁻¹. -2 Pressed under pressure, the cells were cut into discs with a diameter of 10 mm. Using standard CR2032 button cells, the cells were assembled in a glove box (H2O and O2 concentration <1 ppm), with lithium metal sheets used as the negative electrode, Celgard 2500 as the separator, and 1 M LiPF6 EC / DEC (1:1, v:v) as the electrolyte to create a lithium-ion battery. Alternatively, sodium metal sheets were used as the negative electrode, a glass fiber membrane as the separator, and 1 M NaClO4 in PC (100 Vol% with 5.0% FEC 1 M LiPF6) as the electrolyte to create a sodium-ion battery.

[0064] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0065] Example 1: Synthesis of p-BPZ1

[0066] When R1, R2, R3, R4 = H, At that time, the structural formula of p-BPZ1 is as follows:

[0067]

[0068] The synthetic route of p-BPZ1 is as follows: Figure 1 As shown, the specific synthesis steps are as follows:

[0069] Step (1), Synthesis of 5,12-dihydrobenzo[b]phenazine:

[0070] 2,3-Dihydroxynaphthalene (6 g, 37.5 mmol) and o-phenylenediamine (4.05 g, 37.5 mmol) were separately ground and added to a single-necked flask. The mixture was deoxygenated three times using a freeze-vacuum-thaw cycle. The mixture was then reacted in a solid-state environment at 180 °C for 30 minutes. The resulting crude product was cooled to room temperature, ground in a mortar, washed with methanol, acetone, and diethyl ether, respectively, and finally dried under vacuum to obtain a pale yellow powder with a yield of 59%.

[0071] The obtained 5,12-dihydrobenzo[b]phenazine was characterized by 1H NMR and mass spectrometry, and the results are as follows: Figure 4 and Figure 5 As shown.

[0072] Step (2), synthesis of p-BPZ1:

[0073] 5,12-Dihydrobenzo[b]phenazine (350 mg, 1.5 mmol), 1,4-dibromobenzene (354.2 mg, 1.5 mmol), and sodium tert-butoxide (432 mg, 4.5 mmol) were degassed in anhydrous xylene (25 mL) to obtain solution A1; simultaneously, palladium acetate (34 mg, 0.15 mmol) and 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (143 mg, 0.3 mmol) were degassed in anhydrous xylene (10 mL) to obtain solution A2. Solution A2 was added to solution A1 to obtain mixed solution A3. After deoxygenation through three refrigeration pump-thawing cycles, mixed solution A3 was stirred at 120 °C for 24 h under nitrogen atmosphere and reflux condensation conditions, then heated to 140 °C and stirred for 12 h, and finally 0.5 mL of iodobenzene was added for end-capping reaction for 5 h. After cooling to room temperature, the mixture was filtered, and the product was sequentially dispersed in H2O, EtOH, DCM, DMF, THF, EC / DEC (1:1; v:v), and EA using a mortar and ultrasonic method, followed by washing, filtration, and purification. This process was repeated three times, and the product was then vacuum dried to obtain the organic cathode material (p-BPZ1).

[0074] The obtained p-BPZ1 was characterized by mass spectrometry, and the results are as follows: Figure 6 As shown, the degree of polymerization is mainly 5 to 7.

[0075] The morphology of the polymer p-BPZ1 sample was observed using scanning electron microscopy (SEM), such as... Figure 7 The purified polymer p-BPZ1 material was observed to be irregular blocky particles with a size range of 1–5 μm.

[0076] Powder X-ray diffraction (XRD) analysis of the crystal structure of polymer p-PZ, such as... Figure 8The results show two broad diffraction peaks in both the small-angle and wide-angle regions. The two weak and broad diffraction peaks in the wide-angle region indicate that the material has an amorphous structure, reflecting that the π-π packing distance between the oligomer skeletons is effectively suppressed. The broad diffraction peaks in the small-angle region indicate that there is a locally ordered structure among the rigid monomers of the p-PZ chains.

[0077] Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements, such as Figure 9 and Figure 10 As shown, the results indicate that p-BPZ1 decomposes at approximately 347 °C in an air atmosphere and at approximately 406 °C in a nitrogen atmosphere. p-BPZ1 does not undergo melting or phase transition within the temperature range of 0–300 °C, thus meeting the requirements for battery fabrication.

[0078] Example 2: Synthesis of p-BPZ2

[0079] When R1, R2, R3, R4 = H, At that time, the structural formula of p-BPZ2 is as follows:

[0080]

[0081] The synthetic route of p-BPZ2 is as follows: Figure 2 As shown, the specific synthesis steps are as follows:

[0082] Step (1), Synthesis of 5,12-dihydrobenzo[b]phenazine:

[0083] 2,3-Dihydroxynaphthalene (6 g, 37.5 mmol) and o-phenylenediamine (4.05 g, 37.5 mmol) were separately ground and added to a single-necked flask. The mixture was deoxygenated three times using a freeze-vacuum-thaw cycle. The mixture was then reacted in a solid-state environment at 180 °C for 30 minutes. The resulting crude product was cooled to room temperature, ground in a mortar, washed with methanol, acetone, and diethyl ether, respectively, and finally dried under vacuum to obtain a pale yellow powder with a yield of 59%.

[0084] Step (2), synthesis of p-BPZ2:

[0085] Solution B1 was obtained by degassing 5,12-dihydrobenzo[b]phenazine (350 mg, 1.5 mmol), 4,4'-dibromodiphenyl ether (488.8 mg, 1.5 mmol), and sodium tert-butoxide (432 mg, 4.5 mmol) in anhydrous xylene (25 mL). Simultaneously, solution B2 was obtained by degassing palladium acetate (34 mg, 0.15 mmol) and 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (143 mg, 0.3 mmol) in anhydrous xylene (10 mL). Solution B2 was added to solution B1 to obtain mixed solution B3. After deoxygenation via three refrigeration pump-thawing cycles, mixed solution B3 was stirred at 120 °C for 24 h under nitrogen atmosphere and reflux condensation conditions, followed by stirring at 140 °C for 12 h. Finally, 0.5 mL of iodobenzene was added to initiate a capping reaction for 5 h. After cooling to room temperature, the mixture was filtered, and the product was sequentially dispersed in H2O, EtOH, DCM, DMF, THF, EC / DEC (1:1; v:v), and EA using a mortar and ultrasonic method, followed by washing, filtration, and purification. This process was repeated three times, and the product was then vacuum dried to obtain the organic cathode material (p-BPZ2).

[0086] Example 3: Synthesis of p-BPZ3

[0087] When R1, R2, R3, R4 = H, At that time, the structural formula of p-BPZ3 is as follows:

[0088]

[0089] The synthetic route of p-BPZ3 is as follows: Figure 3 As shown, the specific synthesis steps are as follows:

[0090] Step (1), Synthesis of 5,12-dihydrobenzo[b]phenazine:

[0091] 2,3-Dihydroxynaphthalene (6 g, 37.5 mmol) and o-phenylenediamine (4.05 g, 37.5 mmol) were separately ground and added to a single-necked flask. The mixture was deoxygenated three times using a freeze-vacuum-thaw cycle. The mixture was then reacted in a solid-state environment at 180 °C for 30 minutes. The resulting crude product was cooled to room temperature, ground in a mortar, washed with methanol, acetone, and diethyl ether, respectively, and finally dried under vacuum to obtain a pale yellow powder with a yield of 59%.

[0092] Step (2), synthesis of p-BPZ3:

[0093] Solution C1 was obtained by degassing 5,12-dihydrobenzo[b]phenazine (350 mg, 1.5 mmol), bis(4-bromophenyl)methane (485.9 mg, 1.5 mmol), and sodium tert-butoxide (432 mg, 4.5 mmol) in anhydrous xylene (25 mL). Simultaneously, solution C2 was obtained by degassing palladium acetate (34 mg, 0.15 mmol) and 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl (143 mg, 0.3 mmol) in anhydrous xylene (10 mL). Solution C2 was added to solution C1 to obtain mixed solution C3. After deoxygenation via three refrigeration pump-thawing cycles, mixed solution C3 was stirred at 120 °C for 24 h under nitrogen atmosphere and reflux condensation conditions, followed by stirring at 140 °C for 12 h. Finally, 0.5 mL of iodobenzene was added to initiate a capping reaction for 5 h. After cooling to room temperature, the mixture was filtered, and the product was sequentially dispersed in H2O, EtOH, DCM, DMF, THF, EC / DEC (1:1; v:v), and EA using a mortar and ultrasonic method, followed by washing, filtration, and purification. This process was repeated three times, and the product was then vacuum dried to obtain the organic cathode material (p-BPZ3).

[0094] Application Example 1: Lithium-ion batteries

[0095] Using p-BPZ1 prepared in Example 1 as the positive electrode material, the positive electrode material, Super P, and polyvinylidene fluoride were mixed in anhydrous N-methyl-2-pyrrolidone at a weight ratio of 6:3:1. The mixture was thoroughly stirred in a centrifugal mixer (ThinkyARE-300) for 30 min (10 min × 3) until a homogeneous slurry was formed. The slurry was then cast onto a 50 μm thick aluminum foil and dried under vacuum at 65 °C for 12 h, followed by drying at 10 MPa·cm⁻¹. -2 Pressed under pressure, the material is cut into discs with a diameter of 10 mm. The batteries are assembled in a glove box (H2O and O2 concentration <1 ppm) using standard CR2032 button cells, with a lithium metal sheet used as the negative electrode, Celgard 2500 as the separator, and 1 M LiPF6 EC / DEC (1:1, v:v) as the electrolyte, to produce lithium-ion batteries.

[0096] Figure 11 These are the charge-discharge curves of a lithium-ion battery using p-BPZ1 as the positive electrode and lithium foil as the negative electrode at a 1C rate. (The last part, "Li," appears to be incomplete and possibly refers to a different topic.) + The / Li polymer p-BPZ1 achieved a high average battery discharge voltage of 3.7V, while p-BPZ1 achieved an initial discharge capacity of 151mAh / g at 1C, which is close to its theoretical specific capacity of 176mAh / g, indicating that all active sites of p-BPZ1 participated in the electrochemical reaction.

[0097] Figure 12 This is a long-cycle graph showing the charge-discharge performance of a lithium-ion battery using polymer p-BPZ1 as the cathode material at a 1C rate. p-BPZ1 exhibits good cycle stability; the relatively low coulombic efficiency in the first few cycles is due to the formation of a solid electrolyte interface layer. In the subsequent 800 charge / discharge cycles, the coulombic efficiency (CE) of p-BPZ1 approaches 100%, and the capacity retention after 800 cycles is as high as 88%.

[0098] Figure 13 This is a rate cycling diagram of a lithium-ion battery using polymer p-BPZ1 as the cathode material at different rates. The results show that the p-BPZ1-based electrode exhibits high rate performance and high energy density. The average capacities of the p-BPZ1 electrode at 0.5, 1, 2, and 5C are 145, 143, 134, and 106 mAh g⁻¹, respectively. -1 The corresponding energy densities are as high as approximately 540, 529, 495, and 393 Wh / kg. -1 .

[0099] Application Example 2: Sodium-ion Battery

[0100] The organic cathode materials p-BPZ1, Super P, and polyvinylidene fluoride prepared in Example 1 were mixed in anhydrous N-methyl-2-pyrrolidone at a weight ratio of 6:3:1. The mixture was thoroughly stirred in a centrifugal mixer (Thinky ARE-300) for 30 min (10 min × 3) until a homogeneous slurry was formed. The slurry was then cast onto a 50 μm thick aluminum foil and dried in a vacuum at 65 °C for 12 h, followed by drying at 10 MPa·cm⁻¹. -2 Pressed under pressure, the material was cut into discs with a diameter of 10 mm. Using standard CR2032 button cells, the cells were assembled in a glove box (H2O and O2 concentration <1 ppm), with a metallic sodium sheet as the negative electrode, a glass fiber membrane as the separator, and 1 M NaClO4 in PC (100 Vol% with 5.0% FEC 1 M LiPF6) as the electrolyte, thus creating a sodium-ion battery.

[0101] Figure 14 This is the charge-discharge curve of a sodium-ion battery using polymer p-BPZ1 as the positive electrode material according to Example 1 of the present invention at a 1C rate. The p-BPZ1-based electrode exhibited a discharge rate of 161 mAh g / g at a 1C rate in the first cycle. -1 Its specific capacity is comparable to that of lithium-ion batteries.

[0102] Figure 15This is a long-cycle charge-discharge diagram of a sodium-ion battery using polymer p-BPZ1 as the positive electrode material, as shown in Example 1 of the present invention, at a 1C rate. Because sodium has a larger ionic radius than lithium, the capacity decay of sodium-ion batteries is faster than that of lithium-ion batteries. In this invention, polymer p-BPZ1 still retains 70% of its specific capacity after 150 cycles.

[0103] Unless otherwise specified, the raw materials and equipment used in this invention are all commonly used in the field; unless otherwise specified, the methods used in this invention are all conventional methods in the field.

[0104] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, alterations, and equivalent transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A battery positive electrode, characterized in that, The positive electrode of the battery comprises a high-voltage organic electrode material p-BPZR based on azahexanetetraphenyl derivative, a conductive agent, a binder, and a current collector aluminum foil; wherein, the general structural formula of the high-voltage organic electrode material p-BPZR based on azahexanetetraphenyl derivative is: R1, R2, R3, and R4 are each independently selected from one of H, Me, Et, iPr, tBu, OMe, and OEt; Ar selected , , , , , or One of them; n is a natural number between 5 and 8.

2. The positive electrode of the battery according to claim 1, characterized in that, The high-voltage organic electrode material p-BPZR based on azahexanetetrabenzene derivatives was prepared by the following method: Step (1): Synthesis of 5,12-dihydrobenzo[b]phenazine 2,3-Dihydroxynaphthalene and o-phenylenediamine were ground separately and then mixed. The mixture was deoxygenated three times by a freeze-vacuum-melt cycle. The deoxygenated mixture was reacted in a solid phase at 175-180℃ for 30-40 minutes to obtain a crude product. After cooling to room temperature, it was ground and then washed with methanol, acetone and diethyl ether respectively. Finally, it was dried under vacuum to obtain the product 5,12-dihydrobenzo[b]phenazine. Step (2): Synthesis of organic electrode material p-BPZR The 5,12-dihydrobenzo[b]phenazine, aromatic compounds and sodium tert-butoxide obtained in step (1) were degassed in anhydrous xylene to obtain solution I; palladium acetate and 2-bicyclohexylphosphine-2',4',6'-triisopropylbiphenyl were degassed in anhydrous xylene to obtain solution II; Solution II was added to solution I, and after deoxygenation through three refrigeration pump-thawing cycles, mixed solution III was obtained. Mixed solution III was stirred at 120-125°C for 20-24 h under nitrogen atmosphere and reflux condensation conditions, then heated to 135-140°C and stirred for 10-12 h. Finally, iodobenzene was added to carry out the end-capping reaction for 5-7 h, and the crude product was obtained after cooling to room temperature. The crude product was filtered and then dispersed sequentially in H2O, EtOH, DCM, DMF, THF, a 1:1 volume ratio mixed solution of EC and DEC, and EA using a mortar and ultrasonic method. The mixture was then washed, filtered, and purified. After repeating this process several times, the product was vacuum dried to obtain the organic electrode material p-BPZR. The aromatic compound is , or One of them, where X is a halogen.

3. The positive electrode of the battery according to claim 2, characterized in that, In step (1), the molar ratio of 2,3-dihydroxynaphthalene and o-phenylenediamine is 1:1~1.

5.

4. The positive electrode of the battery according to claim 2, characterized in that, In step (2), the molar ratio of 5,12-dihydrobenzo[b]phenazine to the aromatic compound is 1:1.

5.

5. The positive electrode of the battery according to claim 2, characterized in that, In step (2), the molar ratio of palladium acetate, 2-bicyclohexylphosphine-2',4',6'-triisopropylbiphenyl and 5,12-dihydrobenzo[b]phenazine is 0.08–0.15:0.16–0.3:

1.

6. A battery positive electrode according to claim 1, characterized in that... The mass ratio of the high-voltage organic electrode material p-BPZR based on azirabenzene derivatives, the conductive agent, and the binder is 6-9:0.5-3:0.5-3.

7. A metal-ion battery, characterized in that, The positive electrode of the battery as described in any one of claims 1-6 is used.

8. A metal-ion battery according to claim 7, characterized in that, The metal-ion battery includes a lithium-ion battery or a sodium-ion battery.

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