A secondary battery electrode material performance regulation method, a battery preparation method, and a secondary battery

Abstract

The application discloses a secondary battery electrode material performance regulation method, a battery preparation method and a secondary battery, and belongs to the technical field of secondary batteries, and aims to solve the core pain points of low regulation precision, poor batch stability, fuzzy structure-performance mapping, narrow system adaptability and insufficient regeneration performance of retired electrodes of existing secondary batteries. Based on the mass transfer of porous media and the electrochemical reaction kinetics theory, a quantitative correlation model of electrode performance and microstructure parameters is established, corresponding structure modification means and synergistic energy input are matched, microstructure full-process closed-loop regulation is realized through in-situ monitoring and energy feedback coefficient dynamic correction, modified electrodes are obtained through two-dimensional verification, and the application can be extended to secondary battery preparation and retired electrode regeneration. The application can realize accurate quantitative regulation of electrode performance, adapt to all-system commercial secondary batteries, break through the closed loop of the whole life cycle of secondary batteries, and is widely applicable to the fields of new energy power, power grid energy storage, consumer electronics and the like.

Description

Technical Field

[0001] This invention belongs to the field of secondary battery technology, specifically relating to a method for regulating the performance of electrode materials in secondary batteries, a battery preparation method, and a secondary battery. It can also be applied to the field of electrode material regeneration, repair, and recycling of retired secondary batteries. Background Technology

[0002] As a core energy storage device, secondary batteries have been widely used in various fields such as new energy vehicles, grid energy storage, consumer electronics, and power tools. Electrode materials, as a core component of secondary batteries, directly determine carrier transport efficiency, active material utilization, volume change buffering capacity, and interface stability through their micro- and nano-structures. They are the core factors determining the rate performance, cycle life, capacity density, and safety performance of finished secondary batteries. Current mainstream electrode control and battery fabrication technologies all share a common core defect that cannot be avoided: Insufficient control precision and inability to achieve quantitative control in open-loop processes: Traditional electrodes use open-loop preparation processes, which can only roughly adjust the porosity of the electrode sheet through macroscopic parameters such as solid content and rolling pressure. They cannot achieve quantitative and precise control over key microstructure parameters such as pore gradient distribution, carrier transport tortuosity, and active material interface texture. The batch deviation of parameters generally exceeds ±0.2, which ultimately leads to a fluctuation of more than 10% in the performance of the finished battery, failing to meet the customization and consistency requirements of high-performance batteries. Poor performance synergy makes it impossible to achieve a balance of multi-dimensional indicators: Existing control methods can only perform fragmented optimizations on a single performance. For example, the hole-forming process can improve rate performance but will reduce electrode compaction density and cycle stability. Surface coating can improve cycle life but will increase charge transfer resistance. Ultimately, the finished battery cannot meet the multi-dimensional requirements of rate, cycle, capacity and safety, and it is difficult to adapt to the differentiated requirements of different scenarios. The applicability is extremely narrow and there is a lack of a universal control framework: existing control methods are mostly exclusive processes developed for single material systems and single battery types. For example, the pore-forming process of silicon-carbon anodes for lithium-ion batteries cannot be adapted to the modification requirements of hard carbon anodes for sodium-ion batteries. The control schemes of power battery electrodes cannot be directly transferred to energy storage battery systems. Battery development cycles are long and trial-and-error costs are high. There is a lack of a universal control technology framework that can cover the entire system of commercial secondary batteries. The structure-performance mapping is ambiguous, and there is no forward design capability: Existing technologies cannot establish a quantitative correlation model between electrode microstructure parameters and battery performance. Battery development relies heavily on the experience of R&D personnel and repeated trial and error, and cannot achieve forward design of "battery target performance → electrode target microstructure → process parameter adjustment". This results in long R&D cycles and low mass production conversion efficiency. Insufficient recycling capacity for retired batteries: In the field of recycling and reusing retired secondary batteries, existing regeneration and repair technologies can only perform simple purification and lithium replenishment on retired electrode materials. They cannot perform precise and targeted repair on the microstructures that collapse during the cycling process. The performance of recycled materials can only be restored to about 80% of that of new materials. They cannot achieve performance restoration or even improvement. Recycled materials cannot be used in high-end battery scenarios, and the recycling rate is extremely low. Summary of the Invention

[0003] Purpose of the invention In view of the above-mentioned defects in the existing technology, the purpose of this invention is: First, it provides a general-purpose method for precise control of electrode material performance that can be adapted to the entire system of commercial secondary batteries, solving the core pain points of existing technologies such as low control precision, poor adaptability, and insufficient batch stability. Second, it provides a method for preparing secondary batteries based on this modified electrode, so as to achieve precise conversion of electrode performance into battery performance. Third, it provides a high-performance secondary battery product that comprehensively improves overall performance such as rate capability, cycle life, capacity, and safety. Fourth, the above methods will be extended to the field of recycling and reusing retired secondary batteries to achieve high-performance regeneration and repair of retired electrode materials, thus creating a closed-loop technology for the entire life cycle of secondary batteries. Technical solution To achieve the above-mentioned objectives, the present invention adopts the following technical solution: A method for precisely controlling the performance of a secondary battery electrode material includes the following steps: Step 1: Based on the theory of mass transfer kinetics and electrochemical reaction kinetics in porous media, establish a quantitative correlation model between electrode electrochemical performance and microstructure characteristic parameters, and obtain the target microstructure characteristic parameters according to the target performance parameters of the target application scenario; Step 2: Based on the target microstructure feature parameters, match the corresponding multi-dimensional structural modification methods and the corresponding collaborative energy input methods; Step 3: During the structural modification process, the measured values ​​of the electrode's microstructure parameters are obtained in real time through in-situ monitoring. Based on the preset energy feedback coefficient, the energy input parameters are dynamically corrected to achieve closed-loop control of the entire microstructure evolution process. Step 4: Perform dual-dimensional verification of the modified electrode's microstructure parameters and electrochemical performance until both parameters reach the target values. A method for preparing a secondary battery includes the following steps: S1: Modified electrode materials were prepared using the above-mentioned electrode material control method; S2: The modified electrode material is prepared into an electrode sheet, and a corresponding electrolyte, separator, and shell are matched. After assembly, liquid injection, formation, and capacity testing, a secondary battery product is obtained. A secondary battery, wherein the positive and / or negative electrodes of the secondary battery are modified electrode materials prepared using the above-described control method. A method for recycling and reusing retired secondary batteries involves using the aforementioned control method to regenerate and modify the electrode materials of the retired secondary batteries, and then using the modified electrode materials to prepare new secondary batteries. Furthermore, the secondary battery is a commercially available rechargeable secondary battery, including but not limited to lithium-ion batteries, sodium-ion batteries, lithium iron phosphate batteries, lithium manganese oxide batteries, lithium cobalt oxide batteries, lithium-sulfur batteries, lead-carbon batteries, and nickel-metal hydride batteries; its application scenarios include but are not limited to secondary batteries for power applications, secondary batteries for energy storage applications, secondary batteries for consumer electronics applications, and secondary batteries for small power applications. Further, the microstructure characteristic parameters include at least one of the following: pore structure characteristic index Dp, pore tortuosity index Dt, interface texture characteristic coefficient Ds, and pore distribution characteristic index Df; wherein: Pore ​​structure characteristic index Dp: Characterizes the gradient distribution characteristics of multi-level pores in the electrode, and is tested by nitrogen adsorption-desorption method and calculated according to GB / T 21650.2-2008 standard; The channel tortuosity index Dt: characterizes the degree of tortuosity of the carrier transport channel, and is calculated by three-dimensional reconstruction using an X-ray three-dimensional microscope; Interface texture characteristic coefficient Ds: Characterizes the microstructure complexity of the surface of the active material, and is calculated by field emission scanning electron microscopy image analysis; Pore ​​distribution characteristic index Df: Characterizes the continuity and uniformity of pores formed by electrode particle accumulation. It is tested by mercury porosimetry and calculated according to GB / T 21650.1-2008 standard. Furthermore, the quantitative correlation model is a quantitative relationship model between the effective diffusion coefficient of charge carriers within the electrode and the microstructure parameters, expressed as: Deff = D0 × εk1 × (1 / Dt)k2 × C In the formula: Deff is the effective diffusion coefficient of charge carriers; D0 is the intrinsic diffusion coefficient of charge carriers in the active material bulk; ε is the porosity of the electrode sheet; and are model correction coefficients, obtained by fitting experimental data of the material system; C is the structural fundamental constant, which is related to the material system and the preparation process. Furthermore, the energy feedback coefficient α is used to characterize the sensitivity of energy input to the regulation of microstructure evolution. The expression is: α=ΔD / ΔE, where ΔD is the actual change in microstructure parameters and ΔE is the change in energy input. The specific value is obtained through linear fitting of the material system in the preliminary experiment. Beneficial effects Compared with the prior art, the present invention has the following core beneficial effects: Universally compatible across all systems, with a single patent covering the entire industry: This invention constructs a universal control framework that is not bound to specific battery systems, specific electrode materials, or specific application scenarios. It can be adapted to all currently commercially available rechargeable batteries without the need to develop separate processes or lay out patents for different systems, significantly reducing R&D and patent layout costs. Full life-cycle closed-loop protection maximizes commercial value: This patent covers the entire industrial chain of secondary batteries throughout their entire life cycle, from upstream new material modification to midstream battery production and preparation, downstream finished battery products, and end-of-life battery recycling and regeneration. Whether it is a material manufacturer, battery manufacturer, vehicle manufacturer, energy storage manufacturer, or recycling company, as long as they use the core technology or corresponding products of this invention, they will fall within the scope of protection, greatly enhancing the commercial value of the patent and the convenience of rights protection. Ultra-high precision quantitative control and industry-leading batch consistency: Through quantitative correlation model and closed-loop feedback control, the deviation of microstructure characteristic parameters can be controlled to ≤±0.05, and the deviation of battery finished product performance control to ≤3%, which far exceeds the control precision of traditional open-loop process and completely solves the industry pain point of large batch performance fluctuation of battery. Multi-performance synergistic optimization breaks the performance seesaw bottleneck: Through the directional control of multi-scale microstructures, the rate, cycle, capacity and safety performance of the finished battery can be synergistically optimized at the same time, completely breaking the bottleneck of the traditional process that "improving one performance must sacrifice another", and perfectly adapting to the differentiated needs of different scenarios. Achieving a leap in forward design and breaking free from reliance on experience: Based on a core quantitative correlation model, forward design can be achieved from “target battery performance → target electrode microstructure → adjustment of process parameters”, completely eliminating the reliance of traditional battery development on the experience of R&D personnel and shortening the R&D cycle by more than 60%. It is perfectly compatible with existing mass production systems and has strong feasibility: the core process is directly compatible with existing large-scale production lines for rechargeable batteries and recycling lines for retired batteries, without the need for high production line modification costs. It has a mature mass production stability control solution and can quickly realize the transformation from laboratory to industrialization. Filling the gap in retired battery regeneration technology: Through precise microstructure repair, the performance of retired electrode materials can be restored to or even surpass that of brand-new commercial materials, significantly improving the recycling rate and added value of retired batteries, and opening up a green circular loop for the entire life cycle of secondary batteries. Attached Figure Description This instruction manual contains three accompanying drawings, which are described below: Figure 1. Closed-loop flowchart of the entire process for precise control of the performance of secondary battery electrode materials Diagram type: Flowchart, corresponding to the core method of claim 1 of this invention, fully demonstrating the core control logic and the entire process steps of this invention; Block diagram structure: Starting from "target performance input", the entire process is sequentially connected: "performance-microstructure parameter matching → modification method and energy input matching → coordinated control execution → in-situ real-time monitoring → dual-dimensional compliance verification". At the same time, a "parameter correction closed loop" is set up. If the target is not met, it will directly feed back to the energy input and modification method links to form a complete closed loop. Figure 2. Schematic diagram covering the entire life cycle and supply chain of secondary batteries Diagram type: Architecture block diagram, corresponding to the full chain protection scope of this invention, fully demonstrating the entire life cycle of secondary batteries covered by this invention; Block diagram structure: It is divided into four core modules, namely "Electrode material modification module (new materials / retired recycled materials) → Battery preparation module → Battery application module → Retirement recycling module". The retirement recycling module is connected to the electrode material modification module in reverse to form a closed loop of the entire life cycle. Each module is marked with the corresponding claim protection scope. Figure 3. Core logic block diagram of closed-loop feedback control Block diagram type: Logic comparison block diagram, highlighting the core differences between the present invention and the prior art; Block diagram structure: It is divided into two parts, left and right. The left side is the "open-loop control process" of the prior art, and the right side is the "closed-loop control process" of the present invention. The comparison clearly shows the core innovation of the present invention through "in-situ monitoring → dynamic correction of energy feedback coefficient → real-time adjustment of energy input", which solves the pain point of insufficient accuracy of the existing open-loop process. Detailed Implementation The present invention will be further described in detail below with reference to specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments. All embodiments of this invention share the same core inventive concept, meeting the patent singularity requirement and covering the entire range of commercially available secondary batteries. The dual-dimensional acceptance criteria for all electrode modification embodiments are: microstructure characteristic parameter control deviation ≤ ±0.05, and electrochemical performance regulation deviation ≤ 3%. General Implementation Method (Universal Operating Procedure for All Secondary Batteries) This embodiment presents a general implementation process that is not tied to a specific battery system or electrode material. It is applicable to new material modification, regeneration and repair of decommissioned materials, and battery fabrication for all commercial rechargeable batteries. The specific steps are as follows: Target parameter matching: Based on the target performance parameters of the battery target application scenario, the target microstructure feature parameters of the electrode target are matched through a pre-established quantitative correlation model to clarify the parameter tolerance range; Pre-setting of control parameters: Based on the pre-experimental data of the electrode material system, the model correction coefficients k1 and k2 and the structural fundamental constant C are obtained by fitting. The exclusive energy feedback coefficient α is set, and the initial energy input parameters and process window are calculated. Matching of control methods: Based on the target microstructure parameters, match the corresponding multi-dimensional structural modification methods, as well as the synergistic energy input methods that correspond one-to-one with the modification methods; Closed-loop control execution: The structural modification operation is carried out according to the preset process. During the process, the measured values ​​of microstructure parameters are obtained in real time through in-situ monitoring. The energy input parameters are dynamically corrected based on the energy feedback coefficient α to ensure that the microstructure evolves according to the target path. Two-dimensional verification: The modified electrode is subjected to microstructure parameter detection and electrochemical performance testing to determine whether it meets the acceptance criteria; Iterative optimization: If the acceptance criteria are not met, perform parameter correction and closed-loop iteration until both parameters meet the criteria; Battery preparation / recycling: The qualified modified electrode materials are prepared into electrode sheets, and the corresponding electrolyte and separator are matched. After assembly, electrolyte injection, formation and capacity testing, the finished secondary battery is obtained. Example 1: Modification of silicon-carbon anode for lithium-ion batteries and preparation of power batteries Basic information on electrode modification: The application scenario is fast charging system for passenger vehicle power batteries. The raw materials are silicon suboxide precursor (SiO_x, x=0.9, D50=150nm) and high-temperature pitch carbon source. The target electrode performance is: capacity retention ≥85% after 500 cycles and capacity retention ≥60% at 10C rate. Parameter matching: The target microstructure parameters obtained by matching are: Dp=2.19, Ds=2.86, Dt=1.12, tolerance ±0.05; Pre-setting of control: The fitting yielded k1=0.62, k2=0.31, C=0.85. The energy feedback coefficient α=0.85 was set, and the initial process parameters were determined as follows: laser power 120W, pore-forming agent addition 8%, and ultrasonic power 600W. Method matching: The modification method adopts 3D printing gradient porous skeleton + mesoporous-microporous gradient pore creation + active material surface texturing, with corresponding synergistic energy input of laser energy + chemical energy + ultrasonic energy; Execution and Iteration: After the first adjustment, the measured values ​​of Ds=2.81 and Dt=1.17 did not meet the tolerance requirements, and the 10C rate capacity remained at 58.2%, which did not meet the target. The ultrasonic treatment time was extended from 30 min to 45 min, the laser power was corrected to 135W, and the amount of pore-forming agent added was fine-tuned to 8.5%. The second adjustment was then performed. Final electrode results: Microstructure parameters Dp=2.19, Ds=2.85, Dt=1.12, all with deviations ≤±0.04; Electrochemical performance: Capacity retention rate of 85.2% after 500 cycles, 10C rate capacity retention rate of 60.8%, performance deviations ≤1.33%, fully meeting the acceptance criteria; Power battery preparation: Modified silicon-carbon anode is used as the anode, and NCM811 ternary cathode, electrolyte, and separator are matched. After winding, assembly, electrolyte injection, formation and capacity testing, a 50Ah power soft pack battery is prepared. Battery performance: Energy density ≥280Wh / kg, 10C fast charging to 80% SOC in 30 minutes, capacity retention ≥80% after 1500 cycles, successfully passed the full set of safety abuse tests in GB 38031-2020, with no fire or explosion. Example 2: Modification of NCM811 ternary cathode for lithium-ion batteries and preparation of high-power batteries Basic information on electrode modification: The application scenario is high-power energy storage and power battery systems. The raw material is monocrystalline NCM811 (large particles D50=10μm, small particles D50=2μm). The target electrode performance is: ≥80% capacity after 5C charging and ≥90% capacity after 1000 cycles. Parameter matching: The target microstructure parameters obtained by matching are: Df=1.78, Dt=1.15, tolerance ±0.05; Pre-setting of control: The fitting yielded k1=0.71, k2=0.24, C=0.92, the energy feedback coefficient α=0.80, and the initial process parameters were determined as follows: the mixing ratio of large and small particles is 7:3, and the vapor deposition power is 800W; Method matching: The modification method adopts bimodal particle gradient stacking control + vapor deposition phase interface modification, with the corresponding synergistic energy input being mechanical energy + electromagnetic energy; Execution and Iteration: After the first adjustment, the measured Dt=1.19 and Df=1.75, which did not meet the tolerance requirements, and the 5C charging capacity remained at 78.6%, which did not meet the target; the mixing ratio of large and small particles was adjusted to 6.5:3.5, the vapor deposition power was corrected to 900W, and the second adjustment was performed; Final electrode results: microstructure parameters Df=1.78, Dt=1.15, with deviations ≤±0.03; electrochemical performance: 5C charging capacity retention of 80.2%, capacity retention of 90.1% after 1000 cycles, with performance deviations ≤0.25%, fully meeting the acceptance criteria; High-power battery fabrication: A 20Ah energy storage battery was prepared by using a modified NCM811 cathode as the cathode, along with a graphite anode, electrolyte, and separator. Battery performance: ≥92% capacity retention after 3000 2C charge-discharge cycles, ≥85% capacity retention at 5C rate discharge, and ≥70% capacity retention at -20℃ discharge, fully meeting the high power requirements of energy storage and power scenarios. Example 3: Modification of hard carbon anode for sodium-ion batteries and preparation of energy storage batteries Basic information on electrode modification: The application scenario is a long-cycle grid energy storage sodium-ion battery system. The raw material is biomass hard carbon precursor. The target electrode performance is: 0.2C reversible capacity ≥350mAh / g, and capacity retention rate ≥92% after 1000 cycles. Parameter matching: The target microstructure parameters obtained by matching are: Dp=2.21, Ds=2.78, Dt=1.10, tolerance ±0.05; Pre-setting of control: The fitting yielded k1=0.59, k2=0.33, C=0.84, the energy feedback coefficient α=0.78, and the initial process parameters were determined as follows: carbonization temperature 1100℃, vacuum degree 10Pa, heating rate 3℃ / min; Method matching: The modification method of precursor pre-oxidation + vacuum carbonization gradient porosity control + surface texturing is adopted, and the corresponding synergistic energy input is thermal energy + vacuum energy + ultrasonic energy; Execution and Iteration: After the first adjustment, the measured values ​​of Ds=2.72 and Dp=2.26 did not meet the tolerance requirements, and the reversible capacity at 0.2C was 338mAh / g, which did not meet the target. The pre-oxidation time was extended from 2h to 3h, the heating rate was corrected to 2℃ / min, and the holding time was extended from 2h to 4h. The second adjustment was then performed. Final electrode results: Microstructure parameters Dp=2.21, Ds=2.77, Dt=1.10, all with deviations ≤±0.04; Electrochemical performance: 0.2C reversible capacity 356mAh / g, capacity retention rate 92.3% after 1000 cycles, performance deviations ≤1.71%, fully meeting the acceptance criteria; Energy storage battery preparation: A 100Ah sodium-ion energy storage battery was prepared by using a modified hard carbon negative electrode as the negative electrode, and matching it with a Prussian white positive electrode, sodium-ion electrolyte and separator. Battery performance: ≥80% capacity retention after 4000 0.5C charge-discharge cycles, ≥65% capacity retention at -20℃ low temperature discharge, cost is reduced by more than 30% compared to lithium-ion energy storage batteries, fully meeting the long-cycle energy storage requirements of the power grid. Example 4: Modification of Lithium Iron Phosphate Cathode and Preparation of Power Batteries for Commercial Vehicles Basic information on electrode modification: The application scenario is long-cycle commercial vehicle power battery system. The raw material is nano-sized lithium iron phosphate (D50=2μm). The target electrode performance is: capacity retention ≥95% after 3000 1C charge-discharge cycles and capacity retention ≥90% at 2C rate. Parameter matching: The target microstructure parameters obtained by matching are: Df=1.82, Dt=1.08, tolerance ±0.05; Pre-setting parameters: After fitting, k1=0.75, k2=0.22, C=0.94, and the energy feedback coefficient α=0.82, the initial process parameters were determined as follows: particle size distribution ratio 8:2, coating agent addition 1.5%; Method matching: The modification method of multi-gradient particle size distribution regulation + carbon coating phase interface modification is adopted, and the corresponding synergistic energy input is mechanical energy + thermal energy; Execution and Iteration: After the first adjustment, the measured values ​​of Dt=1.12 and Df=1.79 did not meet the tolerance requirements, and the capacity retention rate of 93.8% after 3000 cycles did not meet the target. The particle size distribution ratio was adjusted to 7.5:2.5, and the amount of coating agent was slightly adjusted to 2%. The second adjustment was then performed. Final electrode results: Microstructure parameters Df=1.82, Dt=1.08, with deviations ≤±0.03; Electrochemical performance: Capacity retention rate of 95.2% after 3000 cycles at 1C, and capacity retention rate of 90.5% at 2C rate, with performance deviations ≤0.56%, fully meeting the acceptance criteria; Commercial vehicle battery preparation: A 280Ah lithium iron phosphate power battery was prepared by using modified lithium iron phosphate cathode as the cathode, and matching it with graphite anode, electrolyte and separator. Battery performance: Capacity retention rate ≥80% after 6000 1C charge-discharge cycles, system energy density ≥160Wh / kg, successfully passed the full set of safety tests for commercial vehicle power batteries, and fully meets the requirements of long life and high reliability for commercial vehicles. Example 5: Regeneration, Repair, and Recycling of Decommissioned Ternary Cathode Materials Basic information: The raw material is NCM811 ternary cathode powder obtained from the dismantling of retired passenger vehicle power batteries. After cycling, the material capacity retention rate is only 72% of the initial value, the pore structure collapses and the interface impedance soars; the regeneration target performance is: 0.5C reversible capacity ≥180mAh / g, capacity retention rate ≥90% after 500 cycles, reaching the level of new ternary materials; Parameter matching: The target microstructure parameters obtained by matching are: Df=1.78, Dt=1.15, tolerance ±0.05; Pre-setting of control: The fitting yielded k1=0.70, k2=0.25, C=0.91, the energy feedback coefficient α=0.78, and the initial process parameters were determined as follows: particle size distribution ratio 7:3, vapor deposition power 850W; Method matching: The method of particle size distribution regulation + interface phase repair and modification is adopted, and the corresponding synergistic energy input is mechanical energy + electromagnetic energy; Execution and Results: After closed-loop regulation, the microstructure parameters of the recycled material were Df=1.78 and Dt=1.15, with deviations of ≤±0.03; the electrochemical performance showed a reversible capacity of 182mAh / g at 0.5C and a capacity retention rate of 90.4% after 500 cycles, fully reaching the performance level of new commercial ternary materials. Recycling and reuse: The recycled ternary cathode is used to prepare a 20Ah soft-pack battery. The battery performance is not significantly different from that of the battery prepared with the new materials, and it successfully passed the power battery safety test.

Claims

1. A method for precisely controlling the performance of a secondary battery electrode material, characterized in that, Includes the following steps: Step 1: Based on the theory of mass transfer kinetics and electrochemical reaction kinetics in porous media, establish a quantitative correlation model between electrode electrochemical performance and microstructure characteristic parameters, and obtain the target microstructure characteristic parameters according to the target performance parameters of the target application scenario; Step 2: Based on the target microstructure feature parameters, match the corresponding multi-dimensional structural modification methods and the corresponding collaborative energy input methods; Step 3: During the structural modification process, the measured values ​​of the electrode's microstructure parameters are obtained in real time through in-situ monitoring. Based on the preset energy feedback coefficient, the energy input parameters are dynamically corrected to achieve closed-loop control of the entire microstructure evolution process. Step 4: Perform dual-dimensional verification of the modified electrode's microstructure parameters and electrochemical performance until both parameters reach the target values.

2. The control method according to claim 1, characterized in that, The secondary battery is a commercially available rechargeable secondary battery, including any one of lithium-ion batteries, sodium-ion batteries, lithium iron phosphate batteries, lithium manganese oxide batteries, lithium cobalt oxide batteries, lithium-sulfur batteries, lead-carbon batteries, and nickel-metal hydride batteries.

3. The control method according to claim 1, characterized in that, The application scenarios of the secondary battery include any one of the following: power secondary battery, energy storage secondary battery, consumer electronics secondary battery, and small power secondary battery.

4. The control method according to claim 1, characterized in that, The microstructure characteristic parameters include at least one of the following: pore structure characteristic index Dp, pore tortuosity index Dt, interface texture characteristic coefficient Ds, and pore distribution characteristic index Df. The pore structure characteristic index Dp is used to characterize the gradient distribution characteristics of the multi-level pores of the electrode, the pore tortuosity index Dt is used to characterize the tortuosity of the charge carrier transport channels, the interface texture characteristic coefficient Ds is used to characterize the microstructure complexity of the surface of the active material, and the pore distribution characteristic index Df is used to characterize the continuity and uniformity of the pores formed by the accumulation of electrode particles.

5. The control method according to claim 1, characterized in that, The quantitative correlation model is a quantitative relationship model between the effective diffusion coefficient of charge carriers within the electrode and the microstructure parameters, expressed as: Deff = D0 × εk1 × (1 / Dt)k2 × C In the formula: Deff is the effective diffusion coefficient of charge carriers; D0 is the intrinsic diffusion coefficient of charge carriers in the active material bulk; ε is the porosity of the electrode sheet; and are model correction coefficients, obtained by fitting experimental data of the material system; C is the structural fundamental constant, which is related to the material system and the preparation process.

6. The control method according to claim 1, characterized in that, The energy feedback coefficient α is expressed as: α = ΔD / ΔE, where ΔD is the actual change in the microstructure parameters and ΔE is the change in energy input. The energy feedback coefficient α is obtained through linear fitting of the material system in a preliminary experiment.

7. The control method according to claim 1, characterized in that, The multi-dimensional structural modification methods include at least one of the following: 3D printing porous skeleton construction, pore gradient control, surface texturing, particle size distribution control, phase interface modification, and template carbonization. The coordinated energy input method includes at least one of laser energy, chemical energy, ultrasonic energy, mechanical energy, electromagnetic energy, thermal energy, and vacuum energy, and the energy input method corresponds one-to-one with the structural modification method.

8. The control method according to claim 1, characterized in that, The specific method of closed-loop regulation in step three is as follows: if the measured value of the microstructure parameter is lower than the target value, extend the structural modification treatment time, increase the energy input, and optimize the continuity of the microstructure and the number of reactive sites; if the measured value of the microstructure parameter is higher than the target value, reduce the energy input, shorten the treatment time, optimize the uniformity of the microstructure, and avoid carrier transport obstruction caused by excessive structural complexity.

9. The control method according to claim 1, characterized in that, The acceptance criteria for the dual-dimensional verification described in step four are: microstructure characteristic parameter control deviation ≤ ±0.05, electrochemical performance regulation deviation ≤ 3%.

10. The control method according to claim 2, characterized in that, The secondary battery is a lithium-ion battery, and the electrode material is any one of silicon-based negative electrode, ternary positive electrode, graphite negative electrode, and lithium iron phosphate positive electrode; or the secondary battery is a sodium-ion battery, and the electrode material is any one of hard carbon negative electrode, layered oxide positive electrode, Prussian blue positive electrode, and polyanionic positive electrode.

11. The control method according to claim 1, characterized in that, The secondary battery electrode material is an electrode material obtained from the recycling of retired secondary batteries, including any one of the positive electrode powder, negative electrode powder, and retired electrode sheets obtained from the recycling of retired lithium-ion batteries and retired sodium-ion batteries; the regulation method is used for the regeneration and repair of retired electrode materials, and repairs the pore structure and interface texture of retired materials through microstructure-oriented regulation, thereby restoring and improving the electrochemical performance of the materials.

12. A method for preparing a secondary battery, characterized in that, Includes the following steps: S1: The modified electrode material is prepared by using the control method described in any one of claims 1-11; S2: The modified electrode material is prepared into an electrode sheet, and a corresponding electrolyte, separator, and shell are matched. After assembly, liquid injection, formation, and capacity testing, a secondary battery product is obtained.

13. A secondary battery, characterized in that, The positive and / or negative electrodes of the secondary battery are modified electrode materials prepared using the control method described in any one of claims 1-11.

14. The secondary battery according to claim 13, characterized in that, The secondary battery is a commercially available rechargeable secondary battery, including any one of lithium-ion batteries, sodium-ion batteries, lithium iron phosphate batteries, lithium manganese oxide batteries, lithium cobalt oxide batteries, lithium-sulfur batteries, lead-carbon batteries, and nickel-metal hydride batteries; its application scenarios include any one of power secondary batteries, energy storage secondary batteries, consumer electronics secondary batteries, and small power secondary batteries.

15. A method for recycling and reusing decommissioned secondary batteries, characterized in that, The electrode material of a retired secondary battery is regenerated and modified using the control method described in any one of claims 1-11, and the modified electrode material is used to prepare a new secondary battery.

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