Method for supplementing lithium in all-solid-state battery by using lithium oxide solid electrolyte

Abstract

The invention belongs to the technical field of all-solid-state batteries, and particularly relates to a method for supplementing lithium in an all-solid-state battery by using a lithium oxide solid electrolyte, which comprises the following steps: preparing battery assembly; the method comprises the steps of equipment construction and debugging, electrochemical pre-lithiation treatment, pre-lithiation effect detection, subsequent treatment and battery performance test, and data analysis and optimization. The lithium supplement amount can be carefully controlled by accurately adjusting the current, temperature and time parameters, the lithium loss can be accurately supplemented according to the requirements of different battery systems in the manufacturing process of the all-solid-state battery, the situation of excessive lithium supplement or insufficient lithium supplement is avoided, lithium dendrite growth is possibly caused by excessive lithium supplement, and the lithium loss is reduced. Lithium dendrites grow to pierce the diaphragm, so that the battery is short-circuited; the lithium supplement control is accurate, so that the safety, the consistency and the performance stability of the battery can be improved, and the lithium supplement control method is further suitable for batch production.

Description

Technical Field

[0001] The present invention belongs to the technical field of all-solid-state batteries, and specifically is a method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte. Background Art

[0002] All-solid-state battery is a new type of battery technology that replaces traditional liquid electrolytes with solid electrolytes. Its core structure consists of a solid positive electrode, a negative electrode and an electrolyte. It has the significant advantages of high safety and high energy density. During the first charging process of the all-solid-state battery, a layer of solid electrolyte interface film (SEI film) will be formed on the surface of the negative electrode. This process will consume a large amount of lithium ions from the positive electrode, resulting in irreversible capacity loss of the battery; therefore, lithium replenishment is required.

[0003] China's invention patent publication number CN116885311A discloses a lithium replenishment method for a solid electrolyte film of a lithium battery and its application. The lithium replenishment method for a solid electrolyte film of a lithium battery comprises: pre-plating the solid electrolyte film to pre-plating a lithium-containing compound powder onto the surface of the solid electrolyte film; and heating the solid electrolyte film after the pre-plating treatment to complete the lithium replenishment of the solid electrolyte. The key points of the technical solution are to rapidly heat the film in a short period of time, and after reaching the required temperature, heat the solid electrolyte film adsorbed with the lithium-containing compound, so that the lithium-containing compound is quickly decomposed and replenished in the solid electrolyte film, thereby avoiding the volatilization of lithium during the slow heating process.

[0004] However, the above technology has the following defects: the lithium-containing compound pre-plating method it adopts requires subsequent heat treatment to decompose the lithium-containing compound into lithium oxide and diffuse it into the electrolyte to replenish lithium ions. The heat treatment process may cause uneven lithium ion conduction, thereby affecting the lithium replenishment effect.

[0005] To this end, the present invention provides a method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte. Summary of the Invention

[0006] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0007] The technical solution adopted by the present invention to solve the technical problem is: a method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to the present invention comprises the following steps:

[0008] S1: Preparation for battery assembly; selection of lithium oxide solid electrolyte materials with purity and quality that meet the requirements; preparation of high-purity metallic lithium as the third electrode; preparation of positive and negative electrodes and coating of current collectors; assembly of batteries in sequence; ensuring close contact between components;

[0009] S2: Equipment construction and debugging: correctly connect the battery to the selected pre-lithiation equipment electrochemical workstation and constant potential instrument, debug the equipment, and set the current density, pre-lithiation time and temperature parameters;

[0010] S3: Electrochemical pre-lithiation treatment; selectively using a single constant current pre-lithiation treatment method, or a constant current pre-lithiation treatment method followed by a constant voltage pre-lithiation treatment method;

[0011] S4: Detection of pre-lithiation effects; use electrochemical impedance spectroscopy to test the resistance of the electrolyte interface after pre-lithiation; evaluate the lithium ion conductivity of the lithium oxide solid electrolyte after pre-lithiation by measuring the battery's charge and discharge performance and ionic conductivity;

[0012] S5: Subsequent processing and battery performance testing; performing charge and discharge cycle, energy density and power density tests;

[0013] S6: Data analysis and optimization; collect and analyze pre-lithiation and battery performance test data, identify key influencing factors, and optimize pre-lithiation process parameters.

[0014] Furthermore, the process of obtaining the setting parameters of current density, pre-lithiation time and temperature during the construction and debugging of the S2 pre-lithiation equipment is as follows: first, construct the objective function F(J, t, T), that is,

[0015] Where J is the current density, t is the pre-lithiation time, T is the temperature, and the resistance R of the electrolyte interface after pre-lithiation, the lithium ion conductivity σ, and the energy density E and power density P of the battery are comprehensively considered. ω1, ω2, ω3 and ω4 are weight coefficients for adjusting the importance of each factor in the objective function.

[0016] Furthermore, in the S2 pre-lithiation equipment construction and debugging phase, after constructing the objective function, the current density J, pre-lithiation time t and temperature T are encoded as chromosomes in the genetic algorithm to form an initial population combination (J i , t i , T i ), calculate the objective function value F(J i , t i , T i ), which is used as the fitness value.

[0017] Furthermore, according to the fitness value, the excellent individuals are selected as parents to generate the next generation, the selected parent individuals are crossover operated to generate new offspring individuals, the offspring individuals are mutated, and then the objective function value F(J i , t i , Ti ), and perform selection, crossover, and mutation operations until the termination conditions are met, and the target parameter values of current density J, pre-lithiation time t, and temperature T can be obtained.

[0018] Furthermore, the selection of using a single constant current pre-lithiation treatment mode or first constant current pre-lithiation treatment followed by constant voltage pre-lithiation treatment in the S3 electrochemical pre-lithiation treatment stage is based on the control accuracy requirements of the lithium ion insertion amount and the lithium ion conductivity performance requirements.

[0019] Furthermore, the evaluation of the lithium ion conductivity of the lithium oxide solid electrolyte after pre-lithiation in the S4 pre-lithiation effect detection stage includes two methods: a separate evaluation and a comprehensive evaluation. The resistance evaluation method based on the electrolyte interface in the separate evaluation is:

[0020] The Nyquist plot is obtained by electrochemical impedance spectroscopy and fitted using the Randles circuit model, where the impedance expression of the Randles circuit is:

[0021]

[0022] Where Z is the total impedance, Rs is the solution resistance, Rct is the interfacial charge transfer resistance, and C is the electrolyte bulk resistance. dl is the double layer capacitance, ω is the angular frequency, σ is the Warburg impedance coefficient, j is an imaginary number, and the change rate of the interfacial charge transfer resistance before and after pre-lithiation is calculated. Rct0 is the interface charge transfer resistance before pre-lithiation, It is inversely proportional to the interfacial lithium ion conductivity. For example, assuming that the interfacial charge transfer resistance Rct0 = 30Ω before pre-lithiation, the change rate of the interfacial charge transfer resistance ΔRct / Rct0 after pre-lithiation is:

[0023] Furthermore, the battery-based charge and discharge performance evaluation indicators in the separate evaluation include charge and discharge capacity and coulombic efficiency, wherein the calculation formula of the charge and discharge capacity C is:

[0024]

[0025] Where t1 and t2 are the discharge time intervals, I is the discharge current, m is the mass of the active material, I is the discharge current, and ds is the very short time interval.

[0026] Furthermore, the calculation formula of the coulombic efficiency in the charge and discharge performance evaluation index is: Coulombic efficiency is the ratio of discharge capacity to charge capacity, and the formula is:

[0027]

[0028] Where η is the Coulomb efficiency, C dischargeis the discharge capacity, C charge is the charge capacity, and the coulombic efficiency is proportional to the lithium ion conductivity.

[0029] Furthermore, the ionic conductivity-based evaluation method in the separate evaluation is as follows: prepare a pre-lithiated lithium oxide solid electrolyte sample with a sample thickness of L and a cross-sectional area of A, sandwich the sample between two stainless steel electrodes, apply a DC or AC voltage V, measure the current I passing through the electrolyte sample, and calculate the resistance R=V / I according to Ohm's law. The calculation formula for the ionic conductivity σ is:

[0030]

[0031] Calculate the change rate of ionic conductivity before and after pre-lithiation Where σ0 is the ionic conductivity before pre-lithiation, and the rate of change is proportional to the effect of pre-lithiation on the improvement of ionic conductivity.

[0032] Furthermore, the comprehensive evaluation in the S4 pre-lithiation effect detection stage, i.e., the evaluation results of interface resistance, charge and discharge performance, and ionic conductivity, are comprehensively analyzed. The principle is to establish a comprehensive evaluation index by weighted summing the interface resistance change rate, charge and discharge capacity change rate, and ionic conductivity change rate.

[0033] The beneficial effects of the present invention are as follows:

[0034] 1. By precisely adjusting current, temperature, and time parameters, the amount of lithium replenishment can be meticulously controlled. This means that during the assembly and manufacturing process of all-solid-state batteries, lithium losses can be precisely replenished according to the needs of different battery systems and production processes, avoiding over- or under-replenishment. Over-replenishment can lead to the growth of lithium dendrites, which can pierce the separator, causing a short circuit and thermal runaway. Insufficient lithium replenishment, on the other hand, fails to effectively improve battery performance. Therefore, precise lithium replenishment control helps improve battery safety, consistency, and performance stability, making it suitable for mass production.

[0035] 2. Improved lithium ion conductivity. During the electrochemical pre-lithiation process, metallic lithium reacts with the lithium oxide solid electrolyte interface, and lithium ions are embedded in the electrolyte lattice or interface. This process can repair lithium vacancies in the electrolyte, optimize the lithium ion conduction path, and reduce interface resistance. At the same time, after pre-lithiation, the lithium ion concentration at the electrolyte interface increases, making the migration of lithium ions at the interface smoother, thereby improving the lithium ion conduction efficiency. This is manifested in all-solid-state batteries. Higher lithium ion conductivity can reduce the internal resistance of the battery, increase the power density of the battery, and enable the battery to charge and discharge faster, thereby meeting the fast charging needs of electric vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present invention will be further described below with reference to the accompanying drawings.

[0037] Figure 1 This is a flow chart of a method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to the present invention;

[0038] Figure 2 This is a diagram showing the content of setting parameters for the S2 stage of a method for replenishing lithium using a lithium oxide solid electrolyte in an all-solid-state battery according to the present invention;

[0039] Figure 3 This is a structural display diagram of the evaluation method of the S4 stage of the method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to the present invention. DETAILED DESCRIPTION

[0040] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0041] See also Figure 1-3 This embodiment provides: a method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte, comprising:

[0042] S1: Prepare battery assembly; select lithium oxide solid electrolyte materials with purity and quality that meet the requirements; prepare high-purity metallic lithium as the third electrode; prepare positive and negative electrodes and apply current collectors; assemble the battery in sequence; ensure close contact between components, that is, ensure battery quality from the source. By strictly screening materials and standardizing the assembly process, the probability of battery performance problems is reduced and the consistency and reliability of the battery are improved.

[0043] S2: Equipment construction and debugging: correctly connect the battery to the selected pre-lithiation equipment electrochemical workstation and constant potential instrument, debug the equipment, and set the current density, pre-lithiation time and temperature parameters;

[0044] The process of obtaining the setting parameters of current density, pre-lithiation time and temperature in the S2 pre-lithiation equipment construction and debugging stage is as follows: first, construct the objective function F(J, t, T), that is,

[0045] Therefore, during the electrochemical pre-lithiation process, the present application can carefully control the amount of lithium replenishment by precisely adjusting the current, temperature, and time parameters. For example, when using constant current pre-lithiation, according to Faraday's law, by setting an appropriate current density and pre-lithiation time, the number of lithium ions embedded in the lithium oxide solid electrolyte can be accurately calculated and controlled, as follows:

[0046] Where J is the current density, t is the pre-lithiation time, T is the temperature, and the resistance R of the electrolyte interface after pre-lithiation, the lithium ion conductivity σ, and the energy density E and power density P of the battery are comprehensively considered. ω1, ω2, ω3 and ω4 are weight coefficients for adjusting the importance of each factor in the objective function.

[0047] In the S2 pre-lithiation equipment construction and debugging phase, after constructing the objective function, the current density J, pre-lithiation time t and temperature T are encoded as chromosomes in the genetic algorithm to form an initial population combination (J i , t i , T i ), calculate the objective function value F(J i , t i , T i ), taking it as the fitness value, according to the fitness value, select the best individuals as the parent generation to produce the next generation, perform crossover operation on the selected parent generation individuals, generate new offspring individuals, perform mutation operation on the offspring individuals, and then repeatedly calculate the objective function value F(J i , t i , T i ), and perform selection, crossover and mutation operations until the termination conditions are met, and the target parameter values of current density J, pre-lithiation time t and temperature T can be obtained. For example, the weight coefficients of each factor are ω1=0.3, ω2=0.3, ω3=0.2, ω4=0.2. When initializing the population, 100 groups of parameter combinations (J i , t i , T i ), where J ranges from 0.1-1.0 mA / cm 2 , t ranges from 1 to 10 hours, T ranges from 25 to 60 ° C, and after multiple iterations of optimization, the optimal parameter combination is J = 0.5 mA / cm 2 , t = 5 hours, T = 40 ° C, that is, at this time the resistance of the electrolyte interface and the lithium ion conductivity after pre-lithiation are good, and the overall performance of the battery also reaches a better level.

[0048] Precise controllability allows for accurate replenishment of lithium losses during the all-solid-state battery manufacturing process, based on the needs of different battery systems, to avoid over- or under-replenishment. Over-replenishment may lead to the growth of lithium dendrites, while under-replenishment cannot effectively improve battery performance. Therefore, precise lithium replenishment control helps improve battery consistency and performance stability, and is suitable for the strict control of product quality in large-scale production.

[0049] S3: Electrochemical pre-lithiation treatment; selectively using a single constant current pre-lithiation treatment method, or a constant current pre-lithiation treatment method followed by a constant voltage pre-lithiation treatment method;

[0050] The selection of using a single constant current pre-lithiation treatment method and first constant current pre-lithiation treatment followed by constant voltage pre-lithiation treatment in the S3 electrochemical pre-lithiation treatment stage is based on the control accuracy requirements of the lithium ion embedding amount and the lithium ion conductivity performance requirements.

[0051] Based on the above operations, the pre-lithiation method can be flexibly selected according to different battery systems and research needs to achieve the best pre-lithiation effect. At the same time, constant current pre-lithiation operation is relatively simple, and constant voltage pre-lithiation can better control the degree of pre-lithiation. The combination of the two can more accurately regulate the lithium content inside the battery.

[0052] S4: Detection of pre-lithiation effects; use electrochemical impedance spectroscopy to test the resistance of the electrolyte interface after pre-lithiation; evaluate the lithium ion conductivity of the lithium oxide solid electrolyte after pre-lithiation by measuring the battery's charge and discharge performance and ionic conductivity;

[0053] The evaluation of the lithium ion conductivity of the lithium oxide solid electrolyte after pre-lithiation in the S4 pre-lithiation effect detection stage includes two methods: individual evaluation and comprehensive evaluation. The individual evaluation method based on the resistance of the electrolyte interface is:

[0054] The Nyquist plot is obtained by electrochemical impedance spectroscopy and fitted using the Randles circuit model, where the impedance expression of the Randles circuit is:

[0055]

[0056] Where Z is the total impedance, Rs is the solution resistance, Rct is the interfacial charge transfer resistance, and C is the electrolyte bulk resistance. dl is the double layer capacitance, ω is the angular frequency, σ is the Warburg impedance coefficient, j is an imaginary number, and the change rate of the interfacial charge transfer resistance before and after pre-lithiation is calculated. Rct0 is the interface charge transfer resistance before pre-lithiation, It is inversely proportional to the interfacial lithium ion conductivity. For example, assuming that the interfacial charge transfer resistance before pre-lithiation is Rct0 = 30Ω and Rct = 20Ω, then ΔRct = Rct0-Rct = 30-20 = 10Ω, that is, the rate of change of the interfacial charge transfer resistance after pre-lithiation is This indicates that the interfacial charge transfer resistance is reduced after pre-lithiation, and the interfacial lithium ion conductivity is improved to a certain extent.

[0057] During the electrochemical pre-lithiation process, metallic lithium reacts with the lithium oxide solid electrolyte interface, and lithium ions are embedded in the electrolyte lattice or interface. This process can repair lithium vacancies in the electrolyte, optimize the lithium ion conduction path, and reduce the interface resistance. For example, after pre-lithiation, the lithium ion concentration at the electrolyte interface increases, making the migration of lithium ions at the interface smoother, thereby improving the lithium ion conduction efficiency.

[0058] The battery-based charge and discharge performance evaluation indicators in the separate evaluation include charge and discharge capacity and coulombic efficiency, where the charge and discharge capacity C is calculated as:

[0059]

[0060] Where t1 and t2 are the discharge time intervals, I is the discharge current, m is the mass of active material, I is the discharge current, and ds is the very short time interval. For example, the active material mass of an all-solid-state battery is m = 0.01 kg. During the discharge process, a constant current I = 0.5 A is maintained for discharge. The discharge time is from t1 = 0s to t2 = 3600s, that is, 1 hour;

[0061] Substituting the data into the simplified formula, we can get: At the same time, since 1Ah=3600A·s, it can be converted to capacity unit Ah / kg as follows:

[0062]

[0063] That is, the active material per unit mass of the battery can release 50Ah of electricity during this discharge process.

[0064] The calculation formula of coulombic efficiency in the charge and discharge performance evaluation index is: Coulombic efficiency is the ratio of discharge capacity to charge capacity, and the formula is:

[0065]

[0066] Where η is the Coulomb efficiency, C discharge is the discharge capacity, C charge is the charging capacity, and the coulombic efficiency is proportional to the lithium ion conductivity. For example, continue to use the above battery and assume that during the charging process, the constant current I charge=0.6A charging, charging time e=3000s.

[0067] First calculate the charging capacity, Converted to Ah / kg:

[0068] The above result is 50Ah / kg, Coulomb efficiency This shows that during this charge and discharge process, the battery has almost no charge loss and the lithium ion conductivity is good.

[0069] The improvement of lithium-ion conductivity is directly related to the battery's charge and discharge efficiency. In all-solid-state batteries, higher lithium-ion conductivity can reduce the battery's internal resistance, increase the battery's power density, and enable the battery to charge and discharge faster.

[0070] The ionic conductivity evaluation method used in the separate evaluation is as follows: a pre-lithiated lithium oxide solid electrolyte sample is prepared with a sample thickness of L and a cross-sectional area of A. The sample is sandwiched between two stainless steel electrodes, a DC or AC voltage V is applied, and the current I passing through the electrolyte sample is measured. The resistance R = V / I is calculated according to Ohm's law, and the calculation formula for the ionic conductivity σ is obtained as follows:

[0071]

[0072] Calculate the change rate of ionic conductivity before and after pre-lithiation Where σ0 is the ionic conductivity before pre-lithiation, and the rate of change is proportional to the effect of pre-lithiation on the improvement of ionic conductivity. For example, L = 0.1 cm; A = 1 cm 2 ; V = 5V; I = 0.01A, we can get resistance R = 5V / 0.01A = 500Ω, similarly Assuming that the ionic conductivity before pre-lithiation is σ0 = 0.01 S / m, then Δσ = 0.02 S / m - 0.01 S / m = 0.01 S / m, It shows that the change rate is 1, which means that the ionic conductivity is doubled after pre-lithiation, that is, the lithium ion conductivity performance is optimized.

[0073] In the S4 pre-lithiation effect detection stage, the comprehensive evaluation is to conduct a comprehensive analysis of the evaluation results of interface resistance, charge and discharge performance, and ionic conductivity. The principle is to establish a comprehensive evaluation index by weighted summing the interface resistance change rate, charge and discharge capacity change rate, and ionic conductivity change rate. The formula is expressed as follows: Among them, μ1, μ2, and μ3 are weight coefficients, which can be adjusted according to the specific experimental requirements and the importance of each parameter. is the interfacial charge transfer resistance before pre-lithiation, is the charge-discharge capacity change rate, is the rate of change of ionic conductivity.

[0074] In summary, electrochemical pre-lithiation not only acts on the lithium oxide solid electrolyte itself, but also affects the interface between the electrolyte and the electrode. During the pre-lithiation process, the embedding and redistribution of lithium ions at the interface can improve the chemical composition and structure of the interface and enhance the ion and electron conduction capabilities at the interface. For example, pre-lithiation can reduce side reactions at the interface and form a more stable solid electrolyte interface (SEI) layer, thereby improving interface stability.

[0075] Based on the above operations, this method enables quantitative evaluation of the pre-lithiation effect from multiple perspectives, can accurately determine the degree of improvement of battery performance by pre-lithiation, and provide a basis for further optimization of the pre-lithiation process.

[0076] S5: Subsequent processing and battery performance testing; conduct charge and discharge cycle, energy density and power density tests; that is, by simulating the actual use scenarios of the battery, comprehensively understand the performance characteristics of the battery, and provide a more practical reference for the application and optimization of the battery, that is, to unify practicality.

[0077] Good electrolyte and electrode interface performance helps to improve the cycle stability and coulombic efficiency of the battery. During the battery charge and discharge process, a stable interface can reduce the loss of lithium ions and the degradation of electrode materials, thereby extending the service life of the battery. At the same time, optimized interface performance can also reduce the polarization phenomenon of the battery, increase the energy density of the battery, and enable the battery to store more electrical energy; by precisely controlling the amount of lithium replenishment through electrochemical pre-lithiation, the growth of lithium dendrites can be effectively avoided. The growth of lithium dendrites is a common safety hazard in lithium metal batteries. It can easily pierce the diaphragm, causing the battery to short-circuit, triggering thermal runaway, and causing serious consequences. Electrochemical pre-lithiation can, under appropriate conditions, make lithium ions deposit evenly, avoid excessive local lithium concentration, and thus inhibit the formation of lithium dendrites. Therefore:

[0078] S6: Data analysis and optimization; collect and analyze pre-lithiation and battery performance test data, analyze and identify key influencing factors, and optimize pre-lithiation process parameters. That is, driven by data, achieve precise optimization of the pre-lithiation process, improve R&D efficiency, and reduce costs.

[0079] Electrochemical pre-lithiation is highly compatible with a variety of lithium oxide solid electrolyte systems and electrode materials. Whether it's different types of lithium oxide solid electrolytes (such as garnet and NASICON), or various cathode and anode materials (such as lithium metal anodes and layered oxide cathodes), the electrochemical pre-lithiation parameters can be adjusted to suit their characteristics, achieving effective lithium replenishment.

Claims

1. A method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte, characterized in that: The following steps are involved: S1: Preparation for battery assembly; selection of lithium oxide solid electrolyte materials with purity and quality that meet the requirements; preparation of high-purity metallic lithium as the third electrode; preparation of positive and negative electrodes and coating of current collectors; assembly of batteries in sequence; ensuring close contact between components; S2: Equipment construction and debugging: correctly connect the battery to the selected pre-lithiation equipment electrochemical workstation and constant potential instrument, debug the equipment, and set the current density, pre-lithiation time and temperature parameters; S3: Electrochemical pre-lithiation treatment; selectively using a single constant current pre-lithiation treatment method, or a constant current pre-lithiation treatment method followed by a constant voltage pre-lithiation treatment method; S4: Detection of pre-lithiation effects; use electrochemical impedance spectroscopy to test the resistance of the electrolyte interface after pre-lithiation; evaluate the lithium ion conductivity of the lithium oxide solid electrolyte after pre-lithiation by measuring the battery's charge and discharge performance and ionic conductivity; S5: Subsequent processing and battery performance testing; performing charge and discharge cycle, energy density and power density tests; S6: Data analysis and optimization; collect and analyze pre-lithiation and battery performance test data, identify key influencing factors, and optimize pre-lithiation process parameters.

2. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 1, characterized in that: The process of obtaining the setting parameters of current density, pre-lithiation time and temperature during the construction and debugging phase of the S2 pre-lithiation equipment is as follows: first, construct the objective function F(J, t, T), that is, Where J is the current density, t is the pre-lithiation time, T is the temperature, and the resistance R of the electrolyte interface after pre-lithiation, the lithium ion conductivity σ, and the energy density E and power density P of the battery are comprehensively considered. ω1, ω2, ω3 and ω4 are weight coefficients for adjusting the importance of each factor in the objective function.

3. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 1, characterized in that: In the S2 pre-lithiation equipment construction and debugging phase, after constructing the objective function, the current density J, pre-lithiation time t and temperature T are encoded as chromosomes in the genetic algorithm to form an initial population combination (J i , t i , T i ), calculate the objective function value F(J i , t i , T i ), which is used as the fitness value.

4. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 3, characterized in that: According to the fitness value, the best individuals are selected as parents to generate the next generation. The selected parent individuals are cross-operated to generate new offspring individuals. The offspring individuals are mutated and the objective function value F(J) is calculated repeatedly. i , t i , T i ), and perform selection, crossover, and mutation operations until the termination conditions are met, and the target parameter values of current density J, pre-lithiation time t, and temperature T can be obtained.

5. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 1, characterized in that: The selection of using a single constant current pre-lithiation treatment method and first constant current pre-lithiation treatment followed by constant voltage pre-lithiation treatment in the S3 electrochemical pre-lithiation treatment stage is based on the control accuracy requirements of the lithium ion insertion amount and the lithium ion conductivity performance requirements.

6. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 1, characterized in that: The evaluation of the lithium ion conductivity of the lithium oxide solid electrolyte after pre-lithiation in the S4 pre-lithiation effect detection stage includes two methods: individual evaluation and comprehensive evaluation. The individual evaluation method based on the resistance of the electrolyte interface is: The Nyquist plot is obtained by electrochemical impedance spectroscopy and fitted using the Randles circuit model, where the impedance expression of the Randles circuit is: Where Z is the total impedance, Rs is the solution resistance, Rct is the interfacial charge transfer resistance, and C is the electrolyte bulk resistance. dl is the double layer capacitance, ω is the angular frequency, σ is the Warburg impedance coefficient, j is an imaginary number, and the change rate of the interfacial charge transfer resistance before and after pre-lithiation is calculated. Rct0 is the interface charge transfer resistance before pre-lithiation, It is inversely proportional to the interfacial lithium ion conductivity.

7. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 6, characterized in that: The battery-based charge and discharge performance evaluation indicators in the separate evaluation include charge and discharge capacity and coulombic efficiency, wherein the charge and discharge capacity C is calculated as follows: Where t1 and t2 are the discharge time intervals, I is the discharge current, m is the mass of the active material, I is the discharge current, and ds is the very short time interval.

8. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 6, characterized in that: The calculation formula of the coulombic efficiency in the charge and discharge performance evaluation index is: Coulombic efficiency is the ratio of discharge capacity to charge capacity, and the formula is: Where η is the Coulomb efficiency, C discharge is the discharge capacity, C charge is the charge capacity, and the coulombic efficiency is proportional to the lithium ion conductivity.

9. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 6, characterized in that: The ionic conductivity evaluation method in the separate evaluation is as follows: prepare a pre-lithiated lithium oxide solid electrolyte sample with a thickness of L and a cross-sectional area of A, sandwich the sample between two stainless steel electrodes, apply a DC or AC voltage V, measure the current I passing through the electrolyte sample, and calculate the resistance R=V / I according to Ohm's law. The calculation formula for the ionic conductivity σ is: Calculate the change rate of ionic conductivity before and after pre-lithiation Where σ0 is the ionic conductivity before pre-lithiation, and the rate of change is proportional to the effect of pre-lithiation on the improvement of ionic conductivity.

10. The method for replenishing lithium in an all-solid-state battery using a lithium oxide solid electrolyte according to claim 1, characterized in that: The comprehensive evaluation in the S4 pre-lithiation effect detection stage, i.e., the evaluation results of interface resistance, charge and discharge performance, and ionic conductivity, are comprehensively analyzed. The principle is to establish a comprehensive evaluation index by weighted summing the interface resistance change rate, charge and discharge capacity change rate, and ionic conductivity change rate.

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