A method and system for migrating the thermal decomposition initiation temperature of high-nickel cathode material precursors.

Abstract

This invention discloses a method and system for migrating the thermal decomposition initiation temperature of high-nickel cathode material precursors. Based on chemical reaction mechanisms and expert knowledge, the microscopic chemical reaction process of high-nickel cathode materials is subdivided. According to the segmented results, the reactions of each chemical element participating in the thermal decomposition reaction during the sintering process of high-nickel cathode materials are studied separately. The chemical mechanism of the mixture reaction is analyzed by utilizing the similarity between the reaction processes of the individual elements and the mixture. Based on data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry (DSC) thermal analysis experiments, the differences between the reaction processes of the individual elements and the mixture are studied. Based on these differences and related mechanism analysis, the coupling parts between the reactions are identified. This invention obtains the variation law of the thermal decomposition initiation temperature of the precursor in high-nickel cathode materials, providing a basis for subsequent analysis of phase changes and trajectory tracking of materials, improving sintering efficiency, and enhancing product performance.

Description

Technical Field

[0001] This invention relates to the field of high-nickel cathode material preparation technology, and in particular discloses a method and system for migrating the initiation temperature of precursor thermal decomposition during the preparation of high-nickel cathode materials. Background Technology

[0002] With societal progress and development, the population is continuously increasing, while energy resources are indeed finite, leading to a gradually intensifying energy crisis. Furthermore, energy waste and environmental pollution generated during production processes remain significant and difficult-to-solve problems. Therefore, it is essential to continuously optimize and improve energy utilization and lifestyle practices. Lithium-ion batteries play a crucial role in addressing environmental pollution and resource scarcity, possessing advantages such as high specific capacity and zero pollution, making them one of the most important energy storage devices of the future, thus sparking a research boom. In lithium-ion batteries, the cathode material plays a vital role and is key to their development. The preparation of high-capacity, thermally stable, high-rate-performance, long-life, and low-cost high-performance cathode materials has become a major research task in recent years. Simultaneously, the application and development of ternary cathode materials for lithium-ion batteries have a crucial impact on the use of new energy sources and the promotion and popularization of new energy vehicles.

[0003] Metal oxides are among the most widely used materials. A prime example is high-nickel transition metal layered oxides, which are cathode materials for lithium-ion batteries, such as the multi-cation layered oxide LiNi. x Mn y Co z O2 is widely used in lithium-ion batteries, electric vehicles, and other fields. High-nickel cathode materials (such as LiNi) 0.8 Co 0.1 Mn 0.1 O2 has become one of the most promising materials for lithium-ion battery cathodes due to its high capacity.

[0004] In actual production, roller kilns are typically used to calcine high-nickel cathode materials at high temperatures for extended periods. Within a roller kiln, the sintering environment generally includes a heating section, a constant-temperature section, and a cooling section. Each temperature section is further divided into multiple temperature zones, and the environmental conditions between these zones are interconnected and influence each other. Furthermore, the reactions occurring in each temperature zone differ, and the quality of the sintered product is closely related to factors such as temperature, atmosphere, and sintering time in each zone. Only after several hours of calcination and complex physicochemical reactions can the desired sintered product be obtained. However, there is currently no analysis of the coupled reactions in the sintering process of high-nickel cathode materials, and the reaction mechanism and research methods for the precursor after mixing with the lithium source remain unclear.

[0005] Therefore, existing technologies do not provide analysis of the coupled reactions in the sintering process of high-nickel cathode materials. The reaction mechanism and research methods of the precursor after mixing with the lithium source are unclear, which are technical problems that urgently need to be solved. Summary of the Invention

[0006] This invention provides a method and system for migrating the thermal decomposition initiation temperature of high-nickel cathode material precursors, aiming to solve the technical problems of existing technologies not having coupled reaction analysis for the sintering process of high-nickel cathode materials, and the unclear reaction mechanism and research methods of the precursor after mixing with the lithium source.

[0007] One aspect of the present invention relates to a method for mitigating the thermal decomposition initiation temperature of a high-nickel cathode material precursor, comprising the following steps:

[0008] The microscopic chemical reaction process of high-nickel cathode materials is further subdivided based on chemical reaction mechanisms and expert knowledge;

[0009] Based on the segmented results, the reactions of each chemical element involved in the thermal decomposition reaction during the sintering process of high-nickel cathode material were studied separately.

[0010] By utilizing the similarity between the reaction processes of elements and mixtures, the chemical mechanism of the reaction in mixtures is analyzed;

[0011] Based on the data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments, the differences between the reaction processes of elements and mixtures are studied. Based on these differences and in conjunction with relevant mechanism analysis, the coupling parts between the reactions are identified.

[0012] This study focuses on the coupling component, combining experimental data and chemical mechanisms to propose a modeling method for the coupling component. This method yields the variation relationship of the reaction coupling component under different heating rates. Simultaneously, a corresponding parameter identification method is used to solve for the parameters within the functional relationship obtained for the reaction coupling component.

[0013] Furthermore, in the step of subdividing the microscopic chemical reaction process of high-nickel cathode materials based on chemical reaction mechanisms and expert knowledge, for the long-term and complex sintering process of high-nickel cathode materials, thermogravimetric data obtained from non-isothermal thermogravimetric experiments at a certain heating rate and unit heat flow rate data obtained from differential scanning calorimetry thermal analysis experiments are used, combined with chemical mechanisms and expert knowledge, to segment the thermal decomposition reaction process of high-nickel cathode materials.

[0014] Furthermore, in the step of studying the reactions of each chemical element participating in the thermal decomposition reaction during the sintering process of high-nickel cathode material based on the segmented results, the chemical properties of the precursor element before and after the addition of the lithium source are obtained by using experimental data of the individual reaction of the precursor element and the reaction of the precursor element and the lithium source LiOH·H2O mixture, based on previous research.

[0015] Furthermore, based on the data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments, the differences between the reaction processes of the elemental precursor and the mixture are studied. Based on these differences and in conjunction with relevant mechanism analysis, the coupling parts between each reaction are identified. By comparing the differences between the precursor elemental precursor and the mixture, the coupling parts between multiple reactions in the high-nickel cathode material are found.

[0016] Furthermore, this study investigates the coupling components, combining experimental data and chemical mechanisms to propose a modeling method for these components. This yields the relationship between the reaction coupling components and their changes at different heating rates. Simultaneously, a parameter identification method is employed to solve for the parameters within the functional relationship obtained from the reaction coupling components. The study focuses on the identified microscopic multi-reaction coupling components of the high-nickel cathode material, proposing a modeling method for the migration of the thermal decomposition initiation temperature of the high-nickel cathode material precursor. The modeling method is shown in the following equation:

[0017] T b =f(β)=a*e b*β +c

[0018] Among them, T b β is the onset temperature of thermal decomposition of the precursor in the mixture, a, b, and c are constants.

[0019] Another aspect of the present invention relates to a thermal decomposition initiation temperature migration system for a high-nickel cathode material precursor, comprising:

[0020] The subdivision module is used to subdivide the microscopic chemical reaction process of high-nickel cathode materials based on chemical reaction mechanisms and expert knowledge;

[0021] The first research module is used to study the reactions of each chemical element involved in the thermal decomposition reaction during the sintering process of high-nickel cathode material based on the segmentation results.

[0022] The analysis module is used to analyze the chemical mechanism of the reaction of the mixture by taking advantage of the similarity between the reaction process of the element and the mixture.

[0023] The second research module is used to study the differences between the reaction processes of elements and mixtures based on the data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments. Based on these differences and in conjunction with relevant mechanism analysis, the coupling parts between the reactions are identified.

[0024] The computational module is used to study the coupling part. Combining experimental data and chemical mechanisms, it proposes a modeling method for the corresponding coupling part, obtains the variation relationship of the reaction coupling part under different heating rates, and uses corresponding parameter identification methods to solve the parameters in the functional relationship obtained for the reaction coupling part.

[0025] Furthermore, within the subdivided modules, for the long-term, complex, and ever-changing sintering process of high-nickel cathode materials, thermogravimetric data obtained from non-isothermal thermogravimetric experiments at a certain heating rate and unit heat flow rate data obtained from differential scanning calorimetry thermal analysis experiments are used, combined with chemical mechanisms and expert knowledge, to segment the thermal decomposition reaction process of high-nickel cathode materials.

[0026] Furthermore, in the first research module, based on previous research, experimental data on the reaction of the precursor element alone and experimental data on the reaction of the precursor element and the lithium source LiOH·H2O mixture were used to obtain the chemical properties of the precursor element before and after the addition of the lithium source.

[0027] Furthermore, in the second research module, the coupling between multiple reactions in high-nickel cathode materials is sought by comparing the differences between the precursor element and the mixture.

[0028] Furthermore, the computational module focuses on the microscopic multi-reaction coupling components of the identified high-nickel cathode material, and proposes a modeling method for the migration of the thermal decomposition initiation temperature of the high-nickel cathode material precursor. The modeling method is shown in the following equation:

[0029] T b =f(β)=a*e b*β +c

[0030] Among them, T b β is the onset temperature of thermal decomposition of the precursor in the mixture, a, b, and c are constants.

[0031] The beneficial effects achieved by this invention are as follows:

[0032] This invention provides a method and system for migrating the thermal decomposition initiation temperature of high-nickel cathode material precursors. Based on chemical reaction mechanisms and expert knowledge, the microscopic chemical reaction process of high-nickel cathode materials is subdivided. According to the segmented results, the reactions of each chemical element participating in the thermal decomposition reaction during the sintering process of high-nickel cathode materials are studied separately. The chemical mechanism of the mixture reaction is analyzed by utilizing the similarity between the reaction processes of the elements and the mixture. Based on data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry (DSC) thermal analysis experiments, the differences between the reaction processes of the elements and the mixture are studied. Based on these differences and relevant mechanism analysis, the coupling parts between the reactions are identified. For the coupling parts, a modeling method for the corresponding coupling parts is proposed, combining experimental data and chemical mechanisms, to obtain the variation relationship of the reaction coupling parts under different heating rates. Simultaneously, a corresponding parameter identification method is used to solve for the parameters within the functional relationship obtained for the reaction coupling parts. This invention provides a method and system for migrating the thermal decomposition initiation temperature of high-nickel cathode material precursors. It innovatively analyzes the coupled portion of the thermal decomposition reaction during the sintering process of high-nickel cathode materials, not only studying the reactions of individual elements but also effectively solving the reaction coupling problem after mixing of elements. Simultaneously, it provides a valuable reference for macroscopic phenomena from a microscopic perspective. The invention obtains the variation law of the thermal decomposition initiation temperature of the precursor in high-nickel cathode materials, providing a basis for subsequent analysis of material phase changes and destination tracking, improving sintering efficiency, and enhancing product performance. Attached Figure Description

[0033] Figure 1 This is a schematic flowchart of an embodiment of a method for migrating the thermal decomposition initiation temperature of a high-nickel cathode material precursor provided by the present invention.

[0034] Figure 2 A functional block diagram of an embodiment of a thermal decomposition initiation temperature migration system for a high-nickel cathode material precursor provided by the present invention;

[0035] Figure 3 This is a schematic diagram illustrating the segmentation of the chemical reaction of the high-nickel cathode material of the present invention at a certain heating rate, based on chemical mechanisms and expert knowledge.

[0036] Figure 4 This is a comparison chart of the thermal decomposition start time of the precursor element in this invention and the thermal decomposition start time of the precursor in the mixture.

[0037] Figure 5 The diagram shows the loss function of the particle swarm parameter identification method of the present invention.

[0038] Explanation of icon numbers:

[0039] 10. Sub-module; 20. First research module; 30. Analysis module; 40. Second research module; 50. Calculation module. Detailed Implementation

[0040] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0041] like Figure 1 and Figure 2 As shown, the first embodiment of the present invention proposes a method for migrating the thermal decomposition initiation temperature of a high-nickel cathode material precursor, comprising the following steps:

[0042] Step S100: Based on chemical reaction mechanisms and expert knowledge, the microscopic chemical reaction process of high-nickel cathode materials is further subdivided.

[0043] The experimental samples used in this embodiment are all from the 811 type high-nickel cathode material precursor and the lithium source LiOH·H2O of a lithium-ion battery ternary cathode material manufacturer. The experimental data are from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments conducted using the precursor and the lithium source at different heating rates.

[0044] For the long-term, complex, and ever-changing sintering process of high-nickel cathode materials, thermogravimetric data obtained from non-isothermal thermogravimetric experiments at a certain heating rate and unit heat flow rate data obtained from differential scanning calorimetry (DSC) thermal analysis experiments, combined with chemical mechanisms and expert knowledge, are used to segment the thermal decomposition reaction process of high-nickel cathode materials, such as... Figure 3 As shown:

[0045] ① Thermal decomposition process of LiOH·H2O

[0046] In the kiln, LiOH·H2O undergoes a two-stage decomposition reaction: LiOH·H2O dehydrates to form LiOH at 40–60℃; LiOH decomposes to form Li2O at 460–470℃.

[0047] LiOH·H2O→LiOH+H2O (1)

[0048] 2LiOH (s) →Li2O (s) +H2O (g) (2)

[0049] ②Precursor thermal decomposition process

[0050] The precursor is a high-nickel material. Comparing the thermogravimetric curves of the precursor and Ni(OH)₂ reveals similar thermodynamic properties. Therefore, cobalt and manganese hydroxides are used as auxiliary methods in the study, with the primary focus on their properties. The thermal decomposition of Ni(OH)₂ mainly occurs around 210-800℃.

[0051] Ni(OH)2→NiO+H2O (3)

[0052] Ni(OH)₂ + OH - →NiOOH+H2O (4)

[0053] By segmenting the material into segments, we can analyze its complex microscopic mechanisms, which greatly helps in exploring the microscopic mechanisms of the thermal decomposition reaction process of high-nickel cathode materials and simulating its microscopic evolution.

[0054] Step S200: Based on the segmentation results, the reactions of each chemical element participating in the thermal decomposition reaction during the sintering process of the high-nickel cathode material are studied separately.

[0055] Based on previous research, the chemical properties of the precursor element before and after the addition of the lithium source were obtained by using experimental data of the reaction of the precursor element alone and the reaction of the precursor element with the lithium source LiOH·H2O mixture (hereinafter referred to as the mixture).

[0056] Step S300: Analyze the chemical mechanism of the reaction of the mixture by utilizing the similarity between the reaction process of the element and the mixture.

[0057] The study investigated the changes in the chemical properties of the precursor element before and after the addition of a lithium source, and based on the reaction similarity between the element and the mixture, explored the reasons for the changes in the chemical properties of the mixture.

[0058] Step S400: Based on the data and information from the non-isothermal thermogravimetric experiment and the differential scanning calorimetry thermal analysis experiment, study the differences between the reaction processes of the element and the mixture, and based on these differences, combine them with relevant mechanism analysis to find the coupling parts between the reactions.

[0059] By comparing the differences between the precursor element and the mixture, such as Figure 4 As shown, we are looking for the coupling between multiple reactions in high-nickel cathode materials. The upper lines represent precursor dehydration, and the lower lines represent the mixture.

[0060] Specifically, regarding the initiation time of precursor thermal decomposition, the initiation time of elemental precursor thermal decomposition is compared with the initiation time of precursor thermal decomposition in the mixture, such as... Figure 4As shown in the table. Comparative studies revealed that the dehydration time of the precursor in the mixture was generally earlier than that of the elemental precursor. Analysis of this phenomenon using chemical mechanisms and expert knowledge suggests that the reaction patterns of the mixture and individual precursors / lithium sources differ. Their coexistence lowers the reaction temperature of each other; the presence of lithium causes the precursor to dehydrate earlier, while the presence of transition metals causes the lithium source to melt, decompose, and dehydrate earlier. Based on the above analysis, Table 1 shows partial temperature data for the onset of precursor dehydration at different heating rates. Table 1 shows that the temperature variation patterns conform to the above-described mechanism analysis.

[0061] Table 1. Partial temperature data of the precursor starting to dehydrate under different heating rates.

[0062]

[0063] Step S500: Study the coupling part, combine experimental data and chemical mechanism, propose a modeling method for the corresponding coupling part, obtain the change relationship of the reaction coupling part under different heating rates, and at the same time use the corresponding parameter identification method to solve the parameters in the functional relationship obtained by the reaction coupling part.

[0064] The microscopic multi-reaction coupling mechanism of the identified high-nickel cathode material was investigated, and a modeling method for the migration of the thermal decomposition initiation temperature of the high-nickel cathode material precursor was proposed, as shown in the following formula:

[0065] T b =f(β)=a*e b*β +c(5)

[0066] In formula (5), T b β is the onset temperature of thermal decomposition of the precursor in the mixture, a, b, and c are constants.

[0067] Regarding the relationship between the dehydration initiation temperature and heating rate of the precursor, traditional parameter selection methods, such as k-fold cross-validation, are highly subjective, computationally time-consuming, and have a limited range of manually set parameters, often resulting in suboptimal parameters and failing to achieve optimal overall performance in terms of mean squared error, mean absolute error, and maximum absolute error. In contrast, particle swarm optimization (PSO) offers advantages such as ease of implementation, high accuracy, and fast convergence. Therefore, we consider using the PSO algorithm to identify model parameters. The fitness function of the PSO algorithm is shown in the following formula:

[0068]

[0069] In formula (6), J is the fitness function of the particle swarm optimization algorithm. T is the temperature data obtained from actual experiments. It is a temperature estimate obtained through a mechanistic function.

[0070] To avoid the algorithm getting trapped in local optima, a local adaptive mutation operator is added for adjustment:

[0071]

[0072] In formula (7), w(t) is the weight transferred at time t, j = 1, 2, ..., i = 1, 2, ..., r1 and r2 are random values ​​from 0 to 1, c1 is the local learning factor, c2 is the global learning factor, and V i X i Let p be the particle velocity and position, respectively, and p be the individual optimal position, while BestS be the population optimal position.

[0073] Parameter identification was performed on formula (7), and the results are shown in Table 2, as well as... Figure 5 The loss function of the PSO parameter identification method is shown.

[0074] Table 2. PSO parameter identification results

[0075]

[0076] The method for migrating the thermal decomposition initiation temperature of high-nickel cathode material precursors provided in this embodiment, compared with existing technologies, subdivides the microscopic chemical reaction process of high-nickel cathode materials based on chemical reaction mechanisms and expert knowledge; studies the reactions of each chemical element participating in the thermal decomposition reaction during the sintering process of high-nickel cathode materials according to the segmented results; analyzes the chemical mechanism of the mixture reaction by utilizing the similarity between the reaction processes of the elements and the mixture; studies the differences between the reaction processes of the elements and the mixture based on data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments; and finds the coupling parts between each reaction based on the differences and relevant mechanism analysis. For the coupling parts, a modeling method for the corresponding coupling parts is proposed by combining experimental data and chemical mechanisms, obtaining the variation relationship of the reaction coupling parts under different heating rates. Simultaneously, a corresponding parameter identification method is used to solve the parameters within the functional relationship obtained for the reaction coupling parts. The method for migrating the thermal decomposition initiation temperature of high-nickel cathode material precursors provided in this embodiment is the first to analyze the coupled part of the thermal decomposition reaction during the sintering process of high-nickel cathode materials. It not only studies the reactions of individual elements, but also effectively solves the reaction coupling problem after mixing of elements. At the same time, it provides an effective reference for macroscopic phenomena from a microscopic perspective. It obtains the variation law of the thermal decomposition initiation temperature of precursors in high-nickel cathode materials, which provides a basis for subsequent analysis of phase changes and destination tracking of materials, improving sintering efficiency, and improving product performance.

[0077] Please see Figure 2 , Figure 2 This is a functional block diagram of an embodiment of a thermal decomposition initiation temperature migration system for a high-nickel cathode material precursor provided by the present invention. In this embodiment, the thermal decomposition initiation temperature migration system for a high-nickel cathode material precursor includes a subdivision module 10, a first research module 20, an analysis module 30, a second research module 40, and a calculation module 50. The subdivision module 10 is used to subdivide the microscopic chemical reaction process of the high-nickel cathode material based on chemical reaction mechanisms and expert knowledge. The first research module 20 is used to study the reactions of each chemical element participating in the thermal decomposition reaction during the sintering process of the high-nickel cathode material according to the subdivision results. The analysis module 30 is used to utilize the elements and... The similarity of the reaction process of the mixture is used to analyze the chemical mechanism of the reaction of the mixture; the second research module 40 is used to study the differences between the reaction process of the element and the mixture based on the data and information of non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments. Based on the differences and related mechanism analysis, the coupling parts between each reaction are found; the calculation module 50 is used to study the coupling parts. Combining experimental data and chemical mechanisms, the corresponding modeling method of the coupling parts is proposed, the change relationship of the reaction coupling parts under different heating rates is obtained, and the parameters in the functional relationship obtained by the reaction coupling parts are solved by using the corresponding parameter identification method.

[0078] The experimental samples used in this embodiment are all from the 811 type high-nickel cathode material precursor and the lithium source LiOH·H2O of a lithium-ion battery ternary cathode material manufacturer. The experimental data are from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments conducted using the precursor and the lithium source at different heating rates.

[0079] Sub-module 10 addresses the long-duration, complex, and variable sintering process of high-nickel cathode materials. Utilizing thermogravimetric data obtained from non-isothermal thermogravimetric experiments at a specific heating rate and unit heat flow rate data from differential scanning calorimetry (DSC) thermal analysis, combined with chemical mechanisms and expert knowledge, the thermal decomposition reaction process of high-nickel cathode materials is segmented, such as... Figure 3 As shown:

[0080] ① Thermal decomposition process of LiOH·H2O

[0081] In the kiln, LiOH·H2O undergoes a two-stage decomposition reaction: LiOH·H2O dehydrates to form LiOH at 40–60℃; LiOH decomposes to form Li2O at 460–470℃.

[0082] LiOH·H2O→LiOH+H2O (8)

[0083] 2LiOH(s) →Li2O (s) +H2O (g) (9)

[0084] ②Precursor thermal decomposition process

[0085] The precursor is a high-nickel material. Comparing the thermogravimetric curves of the precursor and Ni(OH)₂ reveals similar thermodynamic properties. Therefore, cobalt and manganese hydroxides are used as auxiliary methods in the study, with the primary focus on their properties. The thermal decomposition of Ni(OH)₂ mainly occurs around 210-800℃.

[0086] Ni(OH)2→NiO+H2O (10)

[0087] Ni(OH)₂ + OH - →NiOOH+H2O (11)

[0088] By segmenting the material into segments, we can analyze its complex microscopic mechanisms, which greatly helps in exploring the microscopic mechanisms of the thermal decomposition reaction process of high-nickel cathode materials and simulating its microscopic evolution.

[0089] Based on previous research, the first research module 20 uses experimental data of the precursor element reacting alone and experimental data of the reaction between the precursor element and the lithium source LiOH·H2O mixture (hereinafter referred to as the mixture) to obtain the chemical properties of the precursor element before and after the addition of the lithium source.

[0090] The analysis module 30 studies the changes in the chemical properties of the precursor element before and after the addition of the lithium source. Based on the reaction similarity between the element and the mixture, it investigates the reasons for the changes in the chemical properties of the mixture.

[0091] The second research module 40 compares the differences between precursor elements and mixtures, such as... Figure 4 As shown, we are looking for the coupling between multiple reactions in high-nickel cathode materials. The upper lines represent precursor dehydration, and the lower lines represent the mixture.

[0092] Specifically, regarding the initiation time of precursor thermal decomposition, the initiation time of elemental precursor thermal decomposition is compared with the initiation time of precursor thermal decomposition in the mixture, such as... Figure 4As shown in the table. Comparative studies revealed that the dehydration time of the precursor in the mixture was generally earlier than that of the elemental precursor. Analysis of this phenomenon using chemical mechanisms and expert knowledge suggests that the reaction patterns of the mixture and individual precursors / lithium sources differ. Their coexistence lowers the reaction temperature of each other; the presence of lithium causes the precursor to dehydrate earlier, while the presence of transition metals causes the lithium source to melt, decompose, and dehydrate earlier. Based on the above analysis, Table 1 shows partial temperature data for the onset of precursor dehydration at different heating rates. Table 3 shows that the temperature variation patterns conform to the above mechanistic analysis.

[0093] Table 3. Partial temperature data of the precursor starting to dehydrate under different heating rates.

[0094]

[0095] The computational module 50 investigates the microscopic multi-reaction coupling components of the identified high-nickel cathode material and proposes a modeling method for the migration of the thermal decomposition initiation temperature of the high-nickel cathode material precursor, as shown in the following formula:

[0096] T b =f(β)=a*e b*β +c(12)

[0097] In formula (12), T b β is the onset temperature of thermal decomposition of the precursor in the mixture, a, b, and c are constants.

[0098] Regarding the relationship between the dehydration initiation temperature and heating rate of the precursor, traditional parameter selection methods, such as k-fold cross-validation, are highly subjective, computationally time-consuming, and have a limited range of manually set parameters, often resulting in suboptimal parameters and failing to achieve optimal overall performance in terms of mean squared error, mean absolute error, and maximum absolute error. In contrast, particle swarm optimization (PSO) offers advantages such as ease of implementation, high accuracy, and fast convergence. Therefore, we consider using the PSO algorithm to identify model parameters. The fitness function of the PSO algorithm is shown in the following formula:

[0099]

[0100] In formula (13), J is the fitness function of the particle swarm optimization algorithm. T is the temperature data obtained from actual experiments. It is a temperature estimate obtained through a mechanistic function.

[0101] To avoid the algorithm getting trapped in local optima, a local adaptive mutation operator is added for adjustment:

[0102]

[0103] In formula (14), w(t) is the weight transferred at time t, j = 1, 2, ..., i = 1, 2, ..., r1 and r2 are random values ​​from 0 to 1, c1 is the local learning factor, c2 is the global learning factor, and V i X i Let p be the particle velocity and position, respectively, and p be the individual optimal position, while BestS be the population optimal position.

[0104] Parameter identification was performed on formula (14), and the results are shown in Table 4, as well as... Figure 5 The loss function of the PSO parameter identification method is shown.

[0105] Table 4. PSO parameter identification results

[0106]

[0107] The high-nickel cathode material precursor thermal decomposition initiation temperature migration system provided in this embodiment, compared with the prior art, employs a subdivision module 10, a first research module 20, an analysis module 30, a second research module 40, and a calculation module 50. Based on chemical reaction mechanisms and expert knowledge, it subdivides the microscopic chemical reaction process of the high-nickel cathode material. According to the segmentation results, it studies the reactions of each chemical element participating in the thermal decomposition reaction during the sintering process of the high-nickel cathode material. Utilizing the similarity between the reaction processes of the elements and the mixture, it analyzes the chemical mechanism of the mixture reaction. Based on data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments, it studies the differences between the reaction processes of the elements and the mixture. Based on these differences and relevant mechanism analysis, it identifies the coupling parts between each reaction. For the coupling parts, it studies them, combining experimental data and chemical mechanisms to propose modeling methods for the corresponding coupling parts, obtaining the variation relationship of the reaction coupling parts under different heating rates. Simultaneously, it uses corresponding parameter identification methods to solve for the parameters within the functional relationship obtained from the reaction coupling parts. The high-nickel cathode material precursor thermal decomposition initiation temperature migration system provided in this embodiment is the first to analyze the coupled part of the thermal decomposition reaction during the sintering process of high-nickel cathode materials. It not only studies the reaction of individual elements, but also effectively solves the reaction coupling problem after the mixing of individual elements. At the same time, it provides an effective reference for macroscopic phenomena from a microscopic perspective. It obtains the variation law of the thermal decomposition initiation temperature of the precursor in high-nickel cathode materials, which provides a basis for subsequent analysis of the phase change and destination tracking of materials, improving sintering efficiency, and improving product performance.

[0108] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if these modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include these modifications and modifications.

Claims

1. A method for migrating the thermal decomposition initiation temperature of a high-nickel cathode material precursor, characterized in that, Includes the following steps: The microscopic chemical reaction process of high-nickel cathode materials is further subdivided based on chemical reaction mechanisms and expert knowledge; Based on the segmented results, the reactions of each chemical element involved in the thermal decomposition reaction during the sintering process of high-nickel cathode material were studied separately. By utilizing the similarity between the reaction processes of elements and mixtures, the chemical mechanism of the reaction in mixtures is analyzed; Based on the data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments, the differences between the reaction processes of elements and mixtures are studied. Based on these differences and in conjunction with relevant mechanism analysis, the coupling parts between the reactions are identified. This study focuses on the coupling component, combining experimental data and chemical mechanisms to propose a modeling method for the coupling component. This method yields the variation relationship of the reaction coupling component under different heating rates. Simultaneously, a corresponding parameter identification method is used to solve for the parameters within the functional relationship obtained for the reaction coupling component.

2. The method for migrating the thermal decomposition initiation temperature of the high-nickel cathode material precursor as described in claim 1, characterized in that, In the step of subdividing the microscopic chemical reaction process of high-nickel cathode materials based on chemical reaction mechanisms and expert knowledge, for the long-term and complex sintering process of high-nickel cathode materials, thermogravimetric data obtained from non-isothermal thermogravimetric experiments at a certain heating rate and unit heat flow rate data obtained from differential scanning calorimetry thermal analysis experiments are used, combined with chemical mechanisms and expert knowledge, to segment the thermal decomposition reaction process of high-nickel cathode materials.

3. The method for migrating the thermal decomposition initiation temperature of the high-nickel cathode material precursor as described in claim 1, characterized in that, In the step of studying the reactions of each chemical element participating in the thermal decomposition reaction during the sintering process of high-nickel cathode material based on the segmented results, the chemical properties of the precursor element before and after the addition of the lithium source are obtained by using experimental data of the individual reaction of the precursor element and experimental data of the reaction of the precursor element and the lithium source LiOH·H2O mixture, based on previous research.

4. The method for migrating the thermal decomposition initiation temperature of the high-nickel cathode material precursor as described in claim 1, characterized in that, The step of studying the differences between the reaction processes of the elemental precursor and the mixture based on the data and information from the non-isothermal thermogravimetric experiment and the differential scanning calorimetry thermal analysis experiment, and finding the coupling parts between each reaction based on the differences and related mechanism analysis, involves comparing the differences between the precursor elemental precursor and the mixture to find the coupling parts between multiple reactions in the high-nickel cathode material.

5. The method for migrating the thermal decomposition initiation temperature of the high-nickel cathode material precursor as described in claim 4, characterized in that, The study focuses on the coupling components, combining experimental data and chemical mechanisms to propose a modeling method for these components. This method yields the relationship between the reaction coupling components at different heating rates. Furthermore, it employs a parameter identification method to solve for the parameters within the functional relationship obtained from the reaction coupling components. Specifically, the study investigates the microscopic multi-reaction coupling components of the identified high-nickel cathode material and proposes a modeling method for the migration of the thermal decomposition initiation temperature of the high-nickel cathode material precursor. The modeling method is shown in the following equation: T b =f(β)=a*e b*β +c Among them, T b β is the onset temperature of thermal decomposition of the precursor in the mixture, a, b, and c are constants.

6. A thermal decomposition initiation temperature migration system for a high-nickel cathode material precursor, characterized in that, include: The subdivision module (10) is used to subdivide the microscopic chemical reaction process of high-nickel cathode materials based on chemical reaction mechanisms and expert knowledge; The first research module (20) is used to study the reactions of each chemical element involved in the thermal decomposition reaction during the sintering process of high-nickel cathode material based on the segmentation results. The analysis module (30) is used to analyze the chemical mechanism of the reaction of the mixture by taking advantage of the similarity between the reaction process of the element and the mixture; The second research module (40) is used to study the differences between the reaction processes of elements and mixtures based on the data and information from non-isothermal thermogravimetric experiments and differential scanning calorimetry thermal analysis experiments. Based on these differences, and in conjunction with relevant mechanism analysis, the coupling parts between each reaction are identified. The calculation module (50) is used to study the coupling part, combine experimental data and chemical mechanism, propose the corresponding modeling method of the coupling part, obtain the change relationship of the reaction coupling part under different heating rates, and at the same time use the corresponding parameter identification method to solve the parameters in the functional relationship obtained by the reaction coupling part.

7. The high-nickel cathode material precursor thermal decomposition initiation temperature migration system as described in claim 6, characterized in that, In the subdivision module (10), for the long-term, complex and ever-changing sintering process of high-nickel cathode materials, the thermogravimetric data obtained by non-isothermal thermogravimetric experiments at a certain heating rate and the unit heat flow rate data obtained by differential scanning calorimetry thermal analysis experiments are used, combined with chemical mechanisms and expert knowledge, to divide the thermal decomposition reaction process of high-nickel cathode materials into segments.

8. The high-nickel cathode material precursor thermal decomposition initiation temperature migration system as described in claim 6, characterized in that, In the first research module (20), based on previous research, the chemical properties of the precursor element before and after the addition of the lithium source are obtained by using experimental data of the reaction of the precursor element alone and experimental data of the reaction of the precursor element and the lithium source LiOH·H2O mixture.

9. The thermal decomposition initiation temperature migration system for high-nickel cathode material precursors as described in claim 6, characterized in that, In the second research module (40), the coupling parts between multiple reactions of high-nickel cathode materials are found by comparing the differences between the precursor element and the mixture.

10. The high-nickel cathode material precursor thermal decomposition initiation temperature migration system as described in claim 9, characterized in that, In the calculation module (50), the microscopic multi-reaction coupling part of the found high-nickel cathode material is studied, and a modeling method for the migration part of the thermal decomposition initiation temperature of the high-nickel cathode material precursor is proposed. The modeling method is shown in the following formula: T b =f(β)=a*e b*β +c Among them, T b β is the onset temperature of thermal decomposition of the precursor in the mixture, a, b, and c are constants.

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