Electron supplement agent, preparation method, alkali metal battery and application

Abstract

The invention belongs to the technical field of electrochemical energy storage batteries, and provides an electron supplementing agent, a preparation method, an alkali metal battery and application. The electron supplementing agent is a solution of a stable compound formed by solvated electrons and electron-deficient organic molecules, and the electron-deficient organic molecules are compounds which have central polycyclic aromatic hydrocarbon structures and are substituted by strong electron withdrawing groups at symmetrical positions of polycyclic aromatic hydrocarbon. The strong electron withdrawing group enables the central polycyclic aromatic hydrocarbon to form an electron-deficient central ring structure, so that a solvated electron can be captured and stabilized, and an e-(at) electron-deficient organic molecular compound is formed. The preparation method of the electron supplementing agent is simple, large-scale production is easy, and the performance of the primary battery can be remarkably improved. The stable solvation electronic application is not limited to primary batteries, can be expanded to the fields of secondary batteries, photoelectrocatalytic conversion, synthetic chemistry, pollutant degradation and the like, and has great application value.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical energy storage battery technology, specifically relating to an electron replenishing agent, a preparation method, an alkali metal battery, and its applications. Background Technology

[0002] Alkali metal batteries, especially lithium primary batteries, are an important category of high-energy-density power sources. They possess significant advantages such as high energy density, long storage life, and low self-discharge rate, playing an irreplaceable role in fields requiring long-term maintenance-free operation, including implantable medical devices, aerospace systems, and remote sensing equipment. The performance of these batteries depends on their cathode material. Existing cathode materials include fluorocarbons (CF3). x Inorganic materials, such as manganese dioxide (MnO2), have been successfully commercialized, and organic compounds with multi-electron reduction mechanisms have been recently reported. However, increasingly demanding operating environments and complex functional specifications place higher demands on the energy density and rate performance of lithium-ion primary batteries. Currently, fluorinated carbon cathodes are generally limited by slow reaction kinetics and low conductivity byproducts that hinder ion transport, resulting in voltage hysteresis and poor rate performance. The application of small organic molecule materials is limited by their high solubility and limited reduction capabilities, failing to fully demonstrate their high energy density advantages.

[0003] Solvated electrons (SOEs) are the smallest anions and strongest reducing particles in nature, playing a crucial role in radiation chemistry, photochemistry, and biochemistry. As a fundamental and highly efficient reducing agent in chemistry, SOEs show immense promise for applications in organic synthesis, biomedical engineering, and environmental wastewater treatment. However, SOEs are prone to rapid property changes and deactivation under radiation decomposition conditions, posing a significant challenge to their research and controllable application in electrochemical systems such as batteries. Achieving long-term stable existence of SOEs in practical battery systems and leveraging their rapid electron transfer advantages remains a critical technological bottleneck in this field.

[0004] In existing technologies, such as Chinese patent CN119864417A, polynitropyrene is disclosed as a positive electrode active material for primary batteries. This technology focuses on improving the specific capacity and energy density of organic materials through molecular design, introducing nitro functional groups, increasing the conjugated system and carbon loading, and adding proton donors. Its technical approach consistently treats nitropyrene as the primary energy storage component, without addressing or solving the common kinetic problems of the aforementioned battery systems. Furthermore, it fails to suggest that nitropyrene-based materials can be used to capture and stabilize highly active solvated electrons, transforming their function from energy storage to conductivity. Summary of the Invention

[0005] In view of the technical problems existing in the field of alkali metal batteries, especially primary batteries, such as low electronic conductivity, slow reaction kinetics, and limited reduction of active materials, the purpose of this invention is to provide a brand-new technical solution, namely, to provide an electron replenishing agent, a preparation method, an alkali metal battery, and its application.

[0006] This invention discovers that a class of organic molecules with specific electron-deficient structures, particularly tetranitropyrene, can effectively delocalize electrons at the center of the pyrene nucleus by having strongly electron-withdrawing groups at their symmetrical positions, forming an electron-deficient central ring structure. This provides an ideal carrier for stable solvated electrons, enabling them to maintain a stable state in the electrolyte and replenish and conduct electrons in a timely manner during battery discharge. Furthermore, its strong reducing ability can promote the effective utilization of organic cathode materials, increase energy density, and reduce voltage polarization.

[0007] The technical solution of this invention is: A first aspect of the present invention is to provide an electron-replenishing agent for alkali metal batteries, wherein the electron-replenishing agent is a solution of a stable complex formed by a solvated electron and an electron-deficient organic molecule, wherein the electron-deficient organic molecule is a compound having a central fused-ring aromatic hydrocarbon structure and having a strongly electron-withdrawing group substituted at a symmetrical position of the fused-ring aromatic hydrocarbon, the strongly electron-withdrawing group causing the central fused-ring aromatic hydrocarbon to form an electron-deficient central ring structure, thereby capturing and stabilizing a solvated electron to form an electron. - @Electron-deficient organic molecular complexes.

[0008] Furthermore, the electron-deficient organic molecule is an organic compound composed of an organic body with a suitable conjugated structure (such as pyrene, anthracene, benzo[a]pyrene, anthracene-anthracene, hexabenzo[a]benzene, etc.) and electron-withdrawing substituents. The electron-withdrawing substituents include one or more of nitro, cyano, sulfonic acid, and trihalomethyl groups. The aforementioned conjugated structure, combined with an appropriate number and substitution positions of electron-withdrawing groups, can form organic molecules with locally electron-deficient structures.

[0009] Furthermore, the electron-deficient organic molecule is tetranitropyrene. The pyrene ring has four strongly electron-withdrawing groups (nitro groups) at its symmetrical positions, which effectively delocalize the electrons at the center of the pyrene nucleus, forming an electron-deficient central ring structure. This provides an ideal carrier for stable solvated electrons, allowing them to maintain a stable state for a relatively long time. Theoretical calculations show that when an electron enters the electron-deficient central ring structure of a tetranitropyrene molecule, the electron is mainly distributed in the conjugated p-π orbitals of the tetranitropyrene, forming a relatively stable complex structure. Figure 1 ).

[0010] A second aspect of the present invention provides a method for preparing the above-mentioned electron-supplementing agent, comprising the following steps: S1: Disperse or dissolve the electron-deficient organic molecules in a solvent or electrolyte with suitable polarity to obtain a suspension; S2: Add alkali metal to the suspension in step S1 and stir the reaction until a uniform and stable dark blue solution is formed. S3: Let the solution obtained in step S2 stand, and take the supernatant to obtain the electron supplement agent.

[0011] Further, in step S1, the solvent with suitable polarity is selected from one or more of ethylene glycol dimethyl ether, tetrahydrofuran, and 1,2-dimethoxypropane; The salts in the electrolyte can be broadly classified into lithium salts and sodium salts based on the alkali metal used in step S2. The lithium salts are selected from one or more of lithium perchlorate (LiClO4), lithium hexafluorophosphate (LiPF6), lithium bis(fluorosulfonyl)imide (LiFSI), and lithium tetrafluoroborate (LiBF4). The sodium salts are selected from one or more of sodium perchlorate (NaClO4), sodium hexafluorophosphate (NaPF6), sodium trifluoromethanesulfonate (NaCF3SO3), and sodium tetrafluoroborate (NaBF4). The solvents in the electrolyte are selected from ether solvents or mixed solvents of ethers and carbonates. The ether solvents are selected from one or more of ethylene glycol dimethyl ether, tetrahydrofuran, 1,2-dimethoxypropane, and 1,4-dioxane. The carbonate solvents are selected from one or more of ethylene carbonate, propylene carbonate, dimethyl carbonate, and diethyl carbonate.

[0012] Further, in step S2, the alkali metal is lithium, sodium, or potassium; the molar ratio of the electron-deficient organic molecule to the alkali metal is (1:5000) to (1:10000); the reaction is carried out at 20-30°C.

[0013] A third aspect of the present invention is to provide an alkali metal battery comprising a negative electrode, a positive electrode, a separator, and an electrolyte, wherein the electrolyte contains an effective amount of the aforementioned electron-compensating agent.

[0014] Furthermore, the negative electrode is an alkali metal lithium, sodium, or potassium; the active material of the positive electrode is an inorganic or organic positive electrode material. The inorganic positive electrode material is selected from one or more of manganese dioxide, carbon fluoride, ferrous sulfide, and vanadium pentoxide, and the organic positive electrode material is selected from one or more of mononitropyrene, dinitropyrene, trinitropyrene, anthraquinone, and 1,5-dinitroanthraquinone. The alkali metal battery is a secondary battery or a primary battery.

[0015] The electron-supplementing agent provided by this invention can effectively supplement and transfer electrons, participate in a variety of reduction reactions involving electron transfer, and effectively alleviate problems such as slow kinetics and voltage polarization in alkali metal primary batteries.

[0016] A fourth aspect of the present invention is to provide the application of the above-mentioned electron-compensating agent in alleviating voltage polarization of alkali metal batteries, improving rate performance, and promoting deep reduction of cathode materials.

[0017] Advantages and beneficial effects of the present invention: 1. In view of the problem that solvated electrons are mostly generated by laser radiation decomposition and are prone to transient property changes and deactivation, making it difficult to stabilize and effectively utilize them under battery operating conditions, this invention uses tetranitropyrene with a special electron-deficient structure as a carrier to stabilize solvated electrons, thereby achieving a relatively stable state of solvated electrons in the battery system.

[0018] 2. In view of the current problems of low electronic conductivity, poor rate performance and slow kinetics of inorganic cathode materials in alkali metal batteries, the present invention provides an electron-supplementing agent based on solvation electron-mediated reaction for use in alkali metal batteries. Its electron-rich structure and relatively stable state can transfer and replenish electrons in a timely manner during the electrode reaction, which greatly improves the rate performance of the battery.

[0019] 3. To address the problems of insufficient reduction reaction and blockage of active sites by byproducts in the application of organic small molecules with multi-electron reduction mechanisms in lithium primary batteries, this invention provides an electron-supplementing agent based on solvation electron mediation. The solvation electrons with strong reducing ability can effectively promote the reduction of positive electrode active material and the decomposition of fluoroethylene carbonate (FEC), expand the reaction range, and reduce the impact of byproducts.

[0020] 4. To address the issues of voltage hysteresis and slow kinetics inherent in inorganic cathode materials for primary lithium batteries, the present invention provides an electron-supplementing agent based on solvation electron-mediated conduction, which can conduct electrons in a timely manner during battery discharge, effectively alleviating problems such as slow electron transport and voltage hysteresis under high current.

[0021] 5. The solvated electron-mediated electron-supplementing agent provided by this invention is low-cost, simple to prepare, and operates under mild conditions, achieving the stable existence and effective application of solvated electrons in battery systems. The application of stabilized solvated electrons is not limited to primary batteries but can be extended to secondary batteries, photoelectrocatalytic conversion, synthetic chemistry, and pollutant degradation. It pioneers a new paradigm for electron-mediated energy storage, opening new avenues for controllable electron transfer in catalysis, biomedical engineering, and quantum materials science. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the electron-supplementing agent in Example 1 of the present invention; Figure 2 Orbital energy distribution diagram of TNP molecules loaded with different electrons in Example 1 of this invention; Figure 3 The 1H NMR spectrum of tetranitropyrene provided in Example 1 of this invention; Figure 4The ultraviolet absorption spectrum of the electron-supplementing agent in Example 1 of this invention; Figure 5 The electron paramagnetic resonance spectrum of the electron-supplementing agent in Example 1 of this invention; Figure 6 In the diagram, 'a' represents the rate performance of a primary Li-MnO2 battery with the base electrolyte containing no electron-compensating agent, and 'b' represents the rate performance of a primary Li-MnO2 battery with the electrolyte containing the electron-compensating agent from Example 1. Figure 7 In the diagram, 'a' represents the rate performance of a Li-DNP primary battery with a base electrolyte containing no electron-compensating agent, and 'b' represents the rate performance of a Li-DNP primary battery with a base electrolyte containing the electron-compensating agent from Example 1. Figure 8 In the diagram, 'a' is the ultraviolet absorption spectrum of Comparative Example 1 provided by the present invention, and 'b' is the electron paramagnetic resonance spectrum of Comparative Example 1 provided by the present invention. Figure 9 The blank battery performance diagram provided by Comparative Example 2 of this invention; Figure 10 The battery performance diagrams for the different component electrolytes of Comparative Example 3 provided by the present invention are shown. Detailed Implementation

[0023] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. The following embodiments are for illustrative purposes only and should not be construed as limiting the scope of the present invention. The scope of protection of the present invention is not limited to the following embodiments.

[0024] Example 1: Preparation of electron-supplementing agents Weigh 0.2 mg of tetranitropyrene (TNP) and add it to 2 mL of dry dimethyl ethylene glycol (DME) solvent. Disperse the solution ultrasonically for 10 minutes to obtain a pale yellow suspension. Add 8 mg of lithium metal to this suspension (always maintain an excess of lithium metal). Stir magnetically at room temperature. After 45 seconds, the suspension gradually transforms into a clear, homogeneous, deep blue solution. After standing for half an hour, collect the supernatant, which is the electron-supplementing agent of this invention. Its structural schematic diagram is shown below. Figure 1 , Figure 1 The electron injection process and the electron density distribution of the functional group orbitals of the TNP molecule that gains an electron are briefly shown. The electrons are mainly distributed in the conjugated π orbitals. Figure 2 The diagram shows the orbital energy distribution of the TNP molecule after loading different numbers of electrons. It can be seen that when the number of electrons is 1e, the energy of its single electron occupied orbital (SOMO) is below 0 eV, indicating a stable state. However, as the number of electrons increases, the energy rises, making it thermodynamically difficult to maintain stability.

[0025] Tetranitropyrene (TNP) Reference: An electrochemically stable 2D covalent organic framework for high-performance organic supercapacitors. Chin. J. Polym. Sci. The method described in 38, 558-564 (2020). doi:10.1007 / s10118-020-2412-z. is as follows: 1.5 g of pulverized pyrene was added to 25 mL of fuming nitric acid cooled to 0 °C. The suspension was stirred for 2 hours, then heated to room temperature and stirred for another 12 hours. The filtered mixture was washed repeatedly with deionized water until neutral, centrifuged repeatedly with dimethyl sulfoxide (DMSO), and the dark filtrate was removed. The resulting yellow powder was thoroughly washed with ethanol and dried to obtain a bright yellow product. After vacuum drying, the product (tetranitropyrene) was obtained. Figure 3 The image shows the 1H NMR spectrum of tetranitropyrene. Two hydrogen atoms with different chemical shifts can be observed in the image, with a peak area ratio of 1:2, which is in good agreement with the structure of tetranitropyrene.

[0026] Figure 4 and Figure 5 The images show the UV spectrum and electron paramagnetic resonance spectrum of the prepared electron-supplementing agent, respectively. Figure 4 The absorption peak around 400 nm is a characteristic absorption peak of the TNP structure, and the absorption peak at 600 nm is a characteristic absorption peak of solvated electrons, indicating that the solution prepared according to the method of Example 1 contains solvated electrons. Figure 5 It can be seen that the electron supplement solution prepared according to Example 1 exhibits a strong single-electron signal in the electron paramagnetic resonance test, indicating the presence of single electrons in the solution.

[0027] Example 2: Application of electron-compensating agents in Li-MnO2 primary batteries Positive electrode preparation: The positive electrode sheet is prepared as follows: Manganese dioxide (MnO2), conductive carbon (Superp), and binder (sodium alginate) are ground and mixed evenly at a mass ratio of 6:3:1. The mixture is then transferred to a homogenizing box, and an appropriate amount of deionized water is added to obtain a slurry. After thorough mixing in a mortar and homogenizer, the slurry is coated onto aluminum foil using a scraper and dried in a vacuum oven at 80℃ for 12 hours. A disc with a diameter of 10 mm is obtained using a die-crushing machine and quickly transferred to a glove box under a high-purity argon atmosphere (O2 < 0.1 ppm, H2O < 0.1 ppm) for later use.

[0028] Electrolyte preparation: The basic electrolyte is 0.5M LiClO4DME / FEC (Vol. 15%). Take 100 mL of the basic electrolyte, add 100 mL of the electron-supplementing agent prepared in Example 1, and mix well.

[0029] Battery assembly: In an argon glove box, using lithium metal sheets as the negative electrode and Celgard 2400 as the separator, the above-mentioned positive electrode and electrolyte are used to assemble CR2032 button batteries.

[0030] Electrochemical testing: Constant current discharge tests were conducted within a voltage range of 3.0~2.0V, using a basic electrolyte as a comparison, and the tests were performed under the same conditions. Figure 6 In diagram 'a', the rate performance of a primary Li-MnO2 battery without the electron-compensating agent is shown; in diagram 'b', the rate performance of a primary Li-MnO2 battery with the electron-compensating agent from Example 1 is shown. Figure 6 It can be seen that, at the same current density, the battery with added electron-compensating electrolyte has a higher discharge specific capacity and operating voltage than the battery using the base electrolyte, especially at 200 mA g. -1 The battery with an electrolyte system containing an electron-compensating agent at a current density has a discharge specific capacity of 128 mAh g. -1 The operating voltage is 2.78V; however, the discharge specific capacity of the battery based on the basic electrolyte system is only 58 mAh g. -1 The operating voltage is 2.67 V, and it exhibits severe discharge capacity decay under high current density. This indicates that the presence of an electron-compensating agent can promote the full reduction reaction of the electrode active material and effectively alleviate voltage polarization.

[0031] Example 3: Application of electron-compensating agents in Li-DNP primary batteries The difference from Example 2 is that manganese dioxide (MnO2) is replaced with dinitropyrene (DNP).

[0032] Electrochemical testing: Constant current discharge tests were conducted within a voltage range of 3.0~2.0V, using a basic electrolyte without electron-replenishing agents as a comparison, and the tests were conducted under the same conditions. Figure 7 Figure 'a' shows the rate performance of a Li-DNP primary battery with a base electrolyte without the electron-compensating agent, and figure 'b' shows the rate performance of a Li-DNP primary battery with a base electrolyte containing the electron-compensating agent from Example 1. Figure 7 It can be seen that at 200 mA g -1 At a current density of , the discharge specific capacity of a battery with an electrolyte system containing an electron-compensating agent is 674 mAh g. -1 The operating voltage is 2.45 V; however, the battery discharge specific capacity of the basic electrolyte system is only 551 mAh g.-1 With an operating voltage of 2.42 V, the battery with added electron-compensating electrolyte at the same current density also had a higher discharge specific capacity and operating voltage than the battery with the basic electrolyte. This indicates that electron-compensating agents can also promote the full reduction reaction of electrode active materials in organic battery systems and alleviate voltage polarization problems.

[0033] Comparative Example 1: Replacing lithium metal with zinc metal in Example 1 and preparing the solution using the same method as in Example 1, a clear solution could not be obtained, and the suspension did not turn dark blue. After standing for 30 min, the supernatant was collected, and the solution composition was denoted as TNP-E-Zn. Replacing the tetranitropyrene molecule in Example 1 with a dinitropyrene molecule and preparing the solution using the same method as in Example 1, a clear solution could not be obtained, and the suspension did not turn dark blue. After standing for 30 min, the supernatant was collected, and the solution composition was denoted as DNP-E-Li. Replacing the dimethyl glycol ether (DME) solvent in Example 1 with dimethyl carbonate (DMC), and preparing the solution using the same method as in Example 1, a clear solution could not be obtained, and the suspension did not turn dark blue. After standing for 30 min, the supernatant was collected, and the solution composition was denoted as TNP-C-Li. The TNP from Example 1 was dissolved in dimethyl ethylene glycol (DME) solvent and ultrasonically stirred to obtain a light yellow suspension. No metal was added, and the suspension was allowed to stand for 30 min. The supernatant was then collected, and the solution composition was denoted as TNP-DME.

[0034] The above four solutions were subjected to ultraviolet absorption spectroscopy and electron paramagnetic resonance tests. Figure 8 In the figure, 'a' represents the result of ultraviolet absorption spectroscopy. As can be seen from the figure, none of the four solutions showed the characteristic absorption peak of solvated electrons. Figure 8 In the figure, 'b' represents the electron paramagnetic resonance (EPR) test results. The graph shows that none of the four solutions exhibited a signal indicating the presence of a single electron. Figure 8 In both a and b, it is indicated that the solution components in Comparative Example 1 do not contain solvated electrons. A solvated electron solution system requires the simultaneous presence of specific organic molecules, metal types, and ether solvents, and a special chemical reaction must occur during the solution preparation process.

[0035] Comparative Example 2: The electrolyte containing the electron-compensating agent in Example 2 and blank aluminum foil (without positive electrode active material) were assembled into a battery strictly according to the method of Example 2, and a constant current discharge test was performed in the voltage range of 3.0~2.0V. Figure 9The battery test results for the blank aluminum foil in the electrolyte prepared with the electron-replenishing agent solution show that its discharge specific capacity is almost negligible. Combined with the test results of Examples 1 and 2, it is shown that the effect of the electron-replenishing agent on improving the discharge specific capacity of the positive electrode active material and alleviating the voltage polarization phenomenon is due to the interaction between the solvated electrons and the positive electrode active material during the discharge process. The presence of the electron-replenishing agent helps to replenish and transfer electrons in a timely manner during the reaction process, promoting a more complete reduction reaction of the positive electrode active material, rather than the electron-replenishing agent itself providing more capacity.

[0036] Comparative Example 3: 0.1 mg of TNP was directly dissolved in 1 mL of 0.5 M LiClO4DME / FEC (Vol. 15%) basic electrolyte, and magnetically stirred for 30 min to obtain a clear solution without adding lithium metal. The resulting clear solution was labeled TNP-E. The supernatants of the three different components in Comparative Example 1—TNP-E-Zn, DNP-E-Li, and TNP-C-Li—were strictly prepared into corresponding electrolytes according to the electrolyte preparation method in Example 2. Following the same method as in Example 2, using MnO2 as the positive electrode active material, the above four electrolytes were assembled into batteries, and tested at 200 mA g in a voltage range of 3.0–2.0 V. -1 The current density was used to perform constant current discharge testing. Figure 10 The battery discharge curves for the corresponding components show that the discharge specific capacities of batteries containing TNP organic molecules and ether solvent components are quite similar, around 90 mAh g⁻¹. -1 The above indicates that in primary lithium batteries, when TNP and lithium metal are present simultaneously in an electrolyte containing ether solvents, a certain amount of solvated electron complexes can be generated during battery discharge, exhibiting a certain degree of electron-replenishing agent effect. However, its performance at the same current density is somewhat inferior to that of directly adding the prepared electron-replenishing agent to the electrolyte. This is because the electron-replenishing agent exists in the battery system at the initial stage of discharge and can promptly replenish and transfer electrons, while in the comparative example, the solvated electron complexes are gradually generated in the later stage of discharge and play their role then. Ester solutions and solutions without TNP cannot generate solvated electron complexes and therefore do not have an electron-replenishing agent effect, resulting in poor battery performance.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An electron-supplementing agent, characterized in that, The electron-replenishing agent is a solution of a stable complex formed by a solvated electron and an electron-deficient organic molecule. The electron-deficient organic molecule is a compound with a central fused-ring aromatic hydrocarbon structure, in which a strongly electron-withdrawing group replaces a symmetrical position of the fused-ring aromatic hydrocarbon. This strongly electron-withdrawing group causes the central fused-ring aromatic hydrocarbon to form an electron-deficient central ring structure, thereby capturing and stabilizing a solvated electron to form an electron. - @Electron-deficient organic molecular complexes.

2. The electron-supplementing agent according to claim 1, characterized in that, The electron-deficient organic molecule is tetranitropyrene.

3. A method for preparing the electron-supplementing agent as described in claim 1 or 2, characterized in that, Includes the following steps: S1: Disperse or dissolve the electron-deficient organic molecules in a solvent or electrolyte with suitable polarity to obtain a suspension; S2: Add alkali metal to the suspension in step S1 and stir the reaction until a solution with uniform color and stability is formed. S3: Let the solution obtained in step S2 stand, and take the supernatant to obtain the electron supplement agent.

4. The preparation method according to claim 3, characterized in that, In step S1, the solvent with suitable polarity is selected from one or more of ethylene glycol dimethyl ether, tetrahydrofuran, and 1,2-dimethoxypropane.

5. The preparation method according to claim 3, characterized in that, The salt in the electrolyte is a lithium salt or a sodium salt; The lithium salt is selected from one or more of lithium perchlorate, lithium hexafluorophosphate, lithium bis(fluorosulfonyl)imide, and lithium tetrafluoroborate; The sodium salt is selected from one or more of sodium perchlorate, sodium hexafluorophosphate, sodium trifluoromethanesulfonate, and sodium tetrafluoroborate.

6. The preparation method according to claim 3, characterized in that, The solvent in the electrolyte is selected from ether solvents or a mixture of ether solvents and carbonate solvents; The ether solvent is selected from one or more of ethylene glycol dimethyl ether, tetrahydrofuran, 1,2-dimethoxypropane, and 1,4-dioxane; Carbonate solvents are selected from one or more of ethylene carbonate, propylene carbonate, dimethyl carbonate, and diethyl carbonate.

7. The preparation method according to claim 3, characterized in that, In step S2, the alkali metal is lithium, sodium, or potassium; the molar ratio of the electron-deficient organic molecule to the alkali metal is (1:5000) to (1:10000); the reaction is carried out at 20-30°C.

8. An alkali metal battery, comprising a negative electrode, a positive electrode, a separator, and an electrolyte, characterized in that, The electrolyte contains an effective amount of the electron-compensating agent as described in claim 1 or 2, or the electron-compensating agent prepared by the method described in any one of claims 3-7.

9. The alkali metal battery according to claim 8, characterized in that, The negative electrode is lithium, sodium, or potassium; the active material of the positive electrode is an inorganic or organic positive electrode material. The inorganic positive electrode material is selected from one or more of manganese dioxide, carbon fluoride, ferrous sulfide, and vanadium pentoxide. The organic positive electrode material is selected from one or more of mononitropyrene, dinitropyrene, trinitropyrene, anthraquinone, and 1,5-dinitroanthraquinone. The alkali metal battery is a secondary battery or a primary battery.

10. The application of the electron-compensating agent according to claim 1 or 2 in alleviating battery voltage polarization, improving rate performance, and promoting deep reduction of cathode materials.

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