Battery design method, device and equipment for lithium precipitation current and lithium precipitation amount and storage medium

Abstract

The invention relates to the technical field of lithium ion batteries, and discloses a battery design method, device and equipment for lithium precipitation current and lithium precipitation quantity and a storage medium, and the method comprises the following steps: in the charging process of a lithium battery, measuring the voltage difference between a surface electrode and a negative electrode of the battery in real time by using a voltage detection circuit; calculating the lithium precipitation current of the battery according to the voltage difference; and obtaining the lithium precipitation capacity of the battery according to the integral of the lithium precipitation current to the time. The method aims at solving the problems that in the prior art, the lithium precipitation phenomenon is poor in real-time monitoring capacity and insufficient in quantitative analysis requirement in the battery fast charging process, and the method can effectively measure the surface lithium precipitation initial SOC, the lithium precipitation current and the lithium precipitation capacity under different electrochemical systems, different battery formulas and different working steps; and a powerful support is provided for evaluating the limit fast charging capability and the limit multiplying power capability of the battery and formulating the limit fast charging capability of the power battery.

Description

Technical Field

[0001] This application relates to the technical field of lithium-ion batteries, and particularly to a battery design method, device, equipment, and storage medium for lithium plating current and lithium plating amount. Background Art

[0002] The popularization of new energy electric vehicles has not only promoted the transformation and upgrading of the automotive industry but also provided strong support for environmental protection and energy sustainable development. However, with the rapid growth of the electric vehicle market, users' requirements for driving range and charging speed are getting higher and higher. To meet these demands, major battery cell manufacturers have invested a large amount of financial resources and personnel in the research and development of fast charging technologies for battery cells. However, fast charging technologies have also brought a series of new challenges, among which the most prominent one is the problem of lithium plating on the negative electrode. Lithium plating will not only reduce the effective capacity of the battery, increase the internal resistance, but also may cause short circuits and safety problems. Therefore, how to effectively detect and control the lithium plating phenomenon has become a hot and difficult issue in the current research on battery fast charging technologies.

[0003] The core goal of fast charging technology is to provide sufficient electric energy for electric vehicles in the shortest possible time. This requires the battery to be able to accept current quickly while maintaining an efficient and stable charging process. However, fast charging will cause large current density and temperature changes inside the battery, thus increasing the risk of lithium plating. In addition to the charging time, users also hope to charge as much electric energy as possible each time to extend the driving range of the electric vehicle. This requires the battery to maintain a high energy density and cycle stability during fast charging. However, the lithium plating phenomenon will significantly reduce the effective capacity of the battery, affecting the user experience. Lithium plating is one of the most serious problems during fast charging. When the potential of the battery negative electrode drops to a certain level, lithium ions cannot be effectively embedded into the negative electrode material but precipitate on the negative electrode surface to form metallic lithium deposits. These precipitated lithium metals will not only reduce the effective capacity of the battery but also may cause safety problems such as short circuits and thermal runaway. Therefore, how to effectively detect and control the lithium plating phenomenon has become a key issue in the current research on battery fast charging technologies. To effectively detect and control the lithium plating phenomenon, researchers have developed a variety of lithium plating detection methods. However, these methods all have certain limitations and cannot meet the requirements for real-time monitoring and quantitative analysis of the lithium plating phenomenon during fast charging. Summary of the Invention

[0004] The main purpose of this application is to provide a battery design method, device, equipment and storage medium for lithium plating current and lithium plating amount, aiming to solve the problems of poor real-time monitoring ability of lithium plating phenomenon and insufficient quantitative analysis demand in the prior art during the fast charging process of the battery. The method of this application can effectively measure the initial SOC of surface lithium plating, lithium plating current and lithium plating capacity under different electrochemical systems, different battery formulations and different working steps, providing strong support for evaluating the ultimate fast charging ability, ultimate rate ability of the battery and formulating the ultimate fast charging ability of power batteries.

[0005] To achieve the above object, this application provides a battery design method for lithium plating current and lithium plating amount, and the battery design method for lithium plating current and lithium plating amount includes:

[0006] During the charging process of the lithium battery, use a voltage detection circuit to measure the voltage difference between the surface electrode of the battery and the negative electrode in real time;

[0007] Calculate the lithium plating current of the battery according to the voltage difference;

[0008] Obtain the lithium plating capacity of the battery by integrating the lithium plating current with respect to time.

[0009] In an embodiment, the step of using a voltage detection circuit to measure the voltage difference between the surface electrode of the battery and the negative electrode in real time during the charging process of the lithium battery further includes:

[0010] Arrange a porous copper foil or a porous copper mesh on the surface of the negative electrode as the surface electrode;

[0011] Establish a connection between the voltage detection circuit, the surface electrode and the negative electrode;

[0012] During the charging process of the lithium battery, use the voltage detection circuit to detect the voltage between the surface electrode and the negative electrode to ensure that the voltage difference between the surface electrode of the battery and the negative electrode can be measured.

[0013] In an embodiment, before the step of calculating the lithium plating current of the battery according to the voltage difference, it further includes:

[0014] Conduct a fast charge test on the battery while monitoring the voltage difference and the total charging current;

[0015] Record the change of the voltage difference and determine the time point when the lithium plating phenomenon of the battery starts.

[0016] In an embodiment, the step of recording the change of the voltage difference and determining the time point when the lithium plating phenomenon of the battery starts further includes:

[0017] Combined with the charging current and charging time of the battery, calculate the current SOC value of the battery;

[0018] When the increment change of the voltage difference starts to appear, determine the critical SOC value corresponding to the occurrence of surface lithium plating in the battery;

[0019] According to the critical SOC value corresponding to the occurrence of surface lithium plating in the battery, determine the starting time point of the lithium plating phenomenon in the battery.

[0020] In one embodiment, the step of calculating the lithium plating current of the battery according to the voltage difference includes:

[0021] According to the starting time of the occurrence of surface lithium plating in the battery, record the increase amount of the voltage difference and the total electronic resistance of the graphite;

[0022] Calculate the lithium plating current according to the increase amount of the voltage difference and the total electronic resistance of the graphite.

[0023] In one embodiment, the step of obtaining the lithium plating capacity of the battery by integrating the lithium plating current with respect to time includes:

[0024] Determine the integration interval according to the starting time point and the ending time of the occurrence of the lithium plating phenomenon;

[0025] Integrate the lithium plating current within the determined integration interval to obtain the lithium plating capacity of the battery.

[0026] In one embodiment, before the step of using a voltage detection circuit to continuously measure the voltage difference between the surface electrode and the negative electrode of the battery during the charging process of the lithium battery, it includes:

[0027] Detect the working state of the battery;

[0028] When the working state of the battery is in a working state without a fault indication, execute the step of using a voltage detection circuit to continuously measure the voltage difference between the surface electrode and the negative electrode of the battery during the charging process of the lithium battery.

[0029] In addition, to achieve the above object, the present application also proposes a battery design device for lithium plating current and lithium plating amount, and the battery design device for lithium plating current and lithium plating amount includes: a voltage detection module, a lithium plating current module, and a lithium plating capacity module;

[0030] The voltage detection module, during the charging process of the lithium battery, uses a voltage detection circuit to continuously measure the voltage difference between the surface electrode and the negative electrode of the battery;

[0031] The lithium plating current module calculates the lithium plating current of the battery according to the voltage difference;

[0032] The lithium plating capacity module obtains the lithium plating capacity of the battery by integrating the lithium plating current with respect to time.

[0033] In addition, to achieve the above object, the present application also provides a battery design device for analyzing lithium plating current and lithium plating amount, the device comprising: a memory, a processor, and a computer program stored on the memory and executable on the processor, the computer program being configured to implement the steps of the battery design method for analyzing lithium plating current and lithium plating amount as described above.

[0034] In addition, to achieve the above object, the present application also provides a computer storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the battery design method for analyzing lithium plating current and lithium plating amount as described above are implemented.

[0035] One or more of the above technical solutions provided by the present application may have the following advantages or at least achieve the following technical effects: The present application discloses a battery design method, device, equipment and storage medium for analyzing lithium plating current and lithium plating amount. The method includes: during the charging process of a lithium battery, using a voltage detection circuit to measure in real time the voltage difference between the surface electrode of the battery and the negative electrode; calculating the lithium plating current of the battery according to the voltage difference; and obtaining the lithium plating capacity of the battery by integrating the lithium plating current over time. The present application aims to solve the problems of poor real-time monitoring ability of lithium plating phenomenon and insufficient quantitative analysis requirements in the prior art during the fast charging process of the battery. The method of the present application can effectively measure the surface lithium plating starting SOC, lithium plating current and lithium plating capacity under different electrochemical systems, different battery formulations and different working steps, providing strong support for evaluating the ultimate fast charging ability, ultimate rate ability of the battery and formulating the ultimate fast charging ability of power batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present application, and for those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0037] Figure 1 It is a schematic flowchart of the first embodiment of the battery design method for analyzing lithium plating current and lithium plating amount of the present application;

[0038] Figure 2 It is a schematic flowchart of the second embodiment of the battery design method for analyzing lithium plating current and lithium plating amount of the present application;

[0039] Figure 3 It is a schematic flowchart of the third embodiment of the battery design method for analyzing lithium plating current and lithium plating amount of the present application;

[0040] Figure 4 This is a schematic flowchart of the fourth embodiment of the battery design method for the lithium plating current and lithium plating amount in this application.

[0041] The realization of the purpose, functional features, and advantages of this application will be further described in conjunction with the embodiments with reference to the accompanying drawings. Specific embodiments

[0042] Next, the technical solutions in the embodiments of this application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope of protection of this application.

[0043] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of this application, then the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0044] In addition, if there are descriptions such as "first", "second", etc. involved in the embodiments of this application, then the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or the solution where A and B are satisfied simultaneously. In addition, the technical solutions between the embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0045] It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0046] This paper presents an innovative built-in surface electrode solution. By detecting the voltage difference between the surface electrode and the negative electrode, it accurately determines the initial State of Charge (SOC) at which surface lithium plating occurs, as well as the current and final amount of lithium plating based on the change in the voltage difference. This solution uses porous conductive materials (such as porous copper foil, porous copper mesh) as surface electrodes, which are compatible with the chemical and electrochemical environment of lithium batteries and do not affect the intercalation and deintercalation process of lithium ions. The built-in surface electrode is the core component of this solution, and its selection needs to meet the following requirements:

[0047] Be compatible with the chemical and electrochemical environment of lithium batteries and do not cause chemical reactions or electrochemical corrosion;

[0048] Do not affect the intercalation and deintercalation process of lithium ions and ensure the normal operation of the battery;

[0049] The material should have a porous structure to increase the surface area and improve the uniformity of current distribution;

[0050] Have a moderate thickness for easy installation inside the power battery.

[0051] Based on the above requirements, this solution selects porous copper foil and porous copper mesh as the electrode materials on the negative electrode surface, and porous aluminum foil and porous aluminum mesh as the electrode materials on the positive electrode surface. These materials are not only consistent with the current collector materials of power batteries, have good electrochemical and chemical stability, but are also easy to process and install.

[0052] During the battery charging process, the voltage difference between the surface electrode and the negative electrode (V_surface - negative) can reflect the distribution of the electron current on the surface of the negative electrode. When the battery is in a stationary state, the value of V_surface - negative is 0; when the battery is charged at a low C-rate with a constant current, V_surface - negative shows a stable value throughout the entire state of charge (SOC), and there is a linear relationship with the charging rate. This is because the electron current gradually decreases through the lithium intercalation reaction in graphite, and the electron resistance of each layer of graphite is the same, resulting in a stable value of V_surface - negative. When lithium plating occurs during fast charging of the battery, the value of V_surface - negative will increase slightly. This is because the lithium plating process generates an additional electron current, leading to an increase in the electron voltage drop. Therefore, by monitoring the change of V_surface - negative, the critical SOC at which surface lithium plating occurs can be quickly identified. Calculation of the lithium plating current and the amount of lithium plating: Based on the information of V_surface - negative, the lithium plating current and the amount of lithium plating can be calculated. By disassembling the battery and observing the morphological changes on the surface of the negative electrode, the occurrence and distribution of the lithium plating phenomenon are verified; by comparing the changes of V_surface - negative at different charging rates, the influence of fast charging on the lithium plating phenomenon is analyzed; according to the calculation results, the variation laws of the lithium plating current and the amount of lithium plating with the charging process are analyzed; the accuracy and reliability of this scheme are evaluated, and improvement and optimization suggestions are put forward. In the low C-rate charge and discharge test, V_surface - negative shows a stable value throughout the entire SOC, and there is a linear relationship between V_surface - negative and the charging rate during the charging process. This verifies the stability and linear relationship of V_surface - negative, providing a reliable basis for subsequent fast charging tests. In the fast charging test, when the battery is charged to a certain SOC, the value of V_surface - negative begins to increase slightly. This indicates that lithium plating starts to occur on the surface of the battery negative electrode at this time. By recording the change of V_surface - negative, the critical SOC at which surface lithium plating occurs can be accurately identified. At the same time, based on the increase amount of V_surface - negative and the total electron resistance of graphite, the lithium plating current and the amount of lithium plating can be calculated. By disassembling the battery and observing the morphological changes on the surface of the negative electrode, it is found that lithium ions can be evenly intercalated into the interior of graphite at the place where the surface electrode is arranged, showing the golden yellow color of lithium-filled graphite. This verifies that the arrangement of the surface electrode has little influence on the normal operation of the battery, and at the same time proves the effectiveness of this scheme. Calculation results of the lithium plating current and the amount of lithium plating: Based on the increase amount of V_surface - negative and the total electron resistance of graphite, the lithium plating current and the amount of lithium plating are calculated. The results show that both the lithium plating current and the amount of lithium plating gradually increase with the progress of the charging process during fast charging. This verifies that this scheme can accurately calculate the lithium plating current and the amount of lithium plating, providing strong support for subsequent battery performance optimization and safety management. This paper proposes an innovative built-in surface electrode scheme. By detecting the voltage difference between the surface electrode and the negative electrode, accurate monitoring of the lithium plating phenomenon during the fast charging process of power batteries is achieved. This scheme uses a porous conductive material as the surface electrode, which is compatible with the chemical and electrochemical environment of lithium batteries and does not affect the lithium ion deintercalation process at the same time. Experimental results show that this scheme can accurately identify the critical SOC at which surface lithium plating occurs and calculate the lithium plating current and the amount of lithium plating.This provides strong support for subsequent battery performance optimization and safety management.

[0053] During the design and manufacturing process of lithium batteries, the phenomenon of lithium plating is an issue that requires key attention. Lithium plating refers to the phenomenon that during the battery charging process, lithium ions cannot be fully embedded into the negative electrode material, but metallic lithium deposits are formed on the surface of the negative electrode. This not only causes loss of battery capacity, but may also trigger internal short circuits in the battery, reducing the safety and cycle life of the battery. Therefore, it is of great significance to develop a battery design method that can monitor and control the lithium plating phenomenon in real time. This application proposes a battery design method for lithium plating current and lithium plating amount in the first embodiment. Please refer to Figure 1 The battery design method for lithium plating current and lithium plating amount includes steps S10 to S30:

[0054] Step S10: During the charging process of the lithium battery, use a voltage detection circuit to measure the voltage difference between the surface electrode of the battery and the negative electrode in real time;

[0055] Step S20: Calculate the lithium plating current of the battery according to the voltage difference;

[0056] Step S30: Obtain the lithium plating capacity of the battery according to the integral of the lithium plating current over time.

[0057] It should be noted that in this embodiment, this application proposes a battery design method for lithium plating current and lithium plating amount. By monitoring the lithium plating situation of the battery in real time, problems and abnormal conditions existing in the production process can be discovered in a timely manner and processed and improved. At the same time, the battery can also be classified and screened according to the lithium plating situation of the battery to ensure the quality and consistency of the battery. The following is a detailed description of the above steps:

[0058] Step S10: Measure the voltage difference between the surface electrode and the negative electrode of the battery in real time. The voltage detection circuit is the core part for real-time monitoring of the battery voltage difference. When designing, the accuracy, response speed, and stability of the circuit need to be considered. The voltage detection circuit usually consists of parts such as high-precision resistors, operational amplifiers, analog-to-digital converters (ADCs), and microcontrollers (MCUs). The high-precision resistor is used for voltage division to reduce the high voltage of the battery to the range acceptable by the ADC; the operational amplifier is used to increase the gain and stability of the circuit; the ADC is used to convert the analog voltage signal into a digital signal for the MCU to process; the MCU is responsible for receiving the data from the ADC and performing subsequent processing and analysis. When designing the circuit, it is necessary to ensure that the input impedance of the circuit is high enough to avoid affecting the battery voltage. At the same time, the filter design of the circuit is also very important to eliminate noise and interference and improve the measurement accuracy. In addition, the temperature characteristics of the circuit need to be considered to ensure stable measurement accuracy at different temperatures. After the circuit is completed, calibration and testing are required. Calibration can be carried out by comparing with a standard voltage source and adjusting the parameters in the circuit to ensure the measurement accuracy. The testing includes static testing and dynamic testing. Static testing is used to verify the measurement accuracy of the circuit in a stable state, and dynamic testing is used to evaluate the response speed and stability of the circuit during the charging and discharging process of the battery. To achieve real-time measurement, high-speed ADCs and MCUs need to be used. The high-speed ADC can quickly collect the battery voltage signal and convert it into a digital signal. The MCU is responsible for processing these digital signals, calculating the voltage difference, and storing or sending the results to other systems for processing. The selection of the sampling frequency needs to be determined according to the charging and discharging characteristics of the battery and the required measurement accuracy. Generally speaking, the higher the sampling frequency, the better the measurement accuracy and real-time performance. However, too high a sampling frequency will also increase the power consumption and data processing volume of the system. Therefore, it is necessary to select an appropriate sampling frequency on the premise of ensuring measurement accuracy and real-time performance. The MCU needs to process the collected data, including filtering, denoising, calibration, etc. The processed data can be stored in the internal memory for subsequent analysis and processing. At the same time, the MCU can also send the data to other systems or devices through the communication interface to achieve remote monitoring and analysis. To achieve real-time measurement, corresponding software needs to be written. The software design needs to consider aspects such as real-time performance, stability, and reliability. At the same time, the software also needs to be optimized to improve the processing speed and reduce the power consumption. For example, mechanisms such as interrupt processing and timers can be used to improve the real-time performance of the software; the processing power consumption and memory occupancy can be reduced by optimizing algorithms and data structures.

[0059] Step S20: Calculate the lithium plating current of the battery based on the voltage difference. To calculate the lithium plating current of the battery based on the voltage difference, a corresponding calculation model needs to be established. The calculation model of the lithium plating current is based on the electrochemical principle of the battery. During the battery charging process, when the battery voltage reaches or exceeds a certain threshold, lithium ions cannot be fully embedded in the negative electrode material, and metallic lithium deposition forms on the surface of the negative electrode. This threshold is usually referred to as the lithium plating voltage. By measuring the difference between the battery voltage and the lithium plating voltage, the magnitude of the lithium plating current can be calculated. Determining some key parameters is required to establish the lithium plating current calculation model, such as the lithium plating voltage, battery internal resistance, electrode materials, etc. These parameters can be obtained through experimental measurements or by referring to relevant literature. Among them, the lithium plating voltage is the core parameter of the model, which determines the occurrence of the lithium plating phenomenon and the magnitude of the lithium plating current. After establishing the model, verification is needed. Verification can be carried out by comparing with experimental data and adjusting the parameters in the model to ensure the accuracy and reliability of the model. At the same time, the scope of application and limitations of the model also need to be considered to make appropriate adjustments and optimizations in practical applications.

[0060] To calculate the lithium plating current, appropriate calculation methods and algorithms need to be adopted. The numerical calculation method is a commonly used calculation method and can be used to solve complex electrochemical equations. In the calculation of the lithium plating current, the numerical calculation method can be used to solve the electrochemical process inside the battery, thereby obtaining the magnitude of the lithium plating current. For example, numerical calculation methods such as the finite element method and the finite difference method can be used for solving. The machine learning algorithm is a data-driven algorithm and can be used to establish the mapping relationship between the battery state and the lithium plating current. By collecting a large amount of battery charge-discharge data and lithium plating current data, the machine learning model can be trained to achieve the prediction and calculation of the lithium plating current. Commonly used machine learning algorithms include support vector machines, neural networks, etc. When calculating the lithium plating current, attention needs to be paid to the calculation accuracy and efficiency. The calculation accuracy determines the accuracy and reliability of the result; the calculation efficiency determines the real-time performance and response speed of the system. Therefore, it is necessary to improve the calculation efficiency on the premise of ensuring the calculation accuracy. For example, techniques such as parallel computing and optimized algorithms can be used to improve the calculation efficiency.

[0061] Step S30: Obtain the lithium plating capacity of the battery by integrating the lithium plating current over time. In the calculation of the lithium plating capacity, the lithium plating current can be regarded as a function of time. By integrating this function, the magnitude of the lithium plating capacity can be obtained. There are various integration methods, such as definite integral and indefinite integral, etc. In the calculation of the lithium plating capacity, the definite integral method is usually adopted. The definite integral method requires determining the upper and lower limits of the integral, that is, the time range of the integral. This range can be determined according to the charge-discharge characteristics of the battery and the required measurement accuracy. First, it is necessary to collect the lithium plating current data of the battery; then, integrate the data according to the integration method and the time range; finally, obtain the magnitude of the lithium plating capacity.

[0062] It should be particularly noted that during the calculation process, attention needs to be paid to the accuracy and integrity of the data to avoid affecting the results. To verify and optimize the calculation results of the lithium deposition capacity, experimental verification and data analysis are required. Experimental verification is carried out by comparing with the standard method to verify the accuracy and reliability of the calculation results. In the experiment, methods such as capacity testing and electrochemical impedance spectroscopy can be used to measure the lithium deposition capacity of the battery and compare it with the calculation results. Through comparison and analysis, the accuracy and reliability of the calculation method can be evaluated, and necessary adjustments and optimizations can be made to the calculation method. Data analysis is to further analyze and process the calculation results. Through data analysis, the charge-discharge characteristics of the battery, the occurrence law of the lithium deposition phenomenon, and the influencing factors can be understood. At the same time, the calculation method can also be improved and optimized according to the data analysis results to improve the calculation accuracy and efficiency. During the verification and optimization process, some optimization strategies need to be adopted to improve the calculation accuracy and efficiency. For example, parallel computing technology can be used to accelerate the calculation process; adaptive integration methods can be used to improve the integration accuracy; machine learning algorithms can be used to establish the mapping relationship between the battery state and the lithium deposition capacity, etc. These optimization strategies can be selected and applied according to the actual situation.

[0063] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar content as that in the above-mentioned first embodiment can be referred to the above introduction and will not be repeated hereinafter. Please refer to Figure 2 , in this embodiment, the step of using the voltage detection circuit to continuously measure the voltage difference between the surface electrode and the negative electrode of the battery during the charging process of the lithium battery further includes:

[0064] Step S11: Arrange a porous copper foil or a porous copper mesh on the surface of the negative electrode as the surface electrode;

[0065] Step S12: Establish a connection between the voltage detection circuit, the surface electrode, and the negative electrode;

[0066] Step S13: During the charging process of the lithium battery, use the voltage detection circuit to detect the voltage between the surface electrode and the negative electrode to ensure that the voltage difference between the surface electrode and the negative electrode of the battery can be measured.

[0067] Specifically, in this embodiment, during the charging process of the lithium battery, real-time monitoring of the internal voltage of the battery is crucial to ensure the safe and efficient operation of the battery. To accurately measure the voltage difference between the surface electrode and the negative electrode inside the battery, an innovative method is proposed in this paper, that is, a porous copper foil or a porous copper mesh is arranged on the surface of the negative electrode as the surface electrode, and a connection is established with the negative electrode through a voltage detection circuit to achieve real-time monitoring of the voltage. This method can not only improve the measurement accuracy but also effectively reflect the voltage distribution and changes inside the battery, providing strong support for battery management and control. The following is a detailed description of the above steps:

[0068] Step S11: Arrange a porous copper foil or a porous copper mesh on the surface of the negative electrode as the surface electrode. Both the porous copper foil and the porous copper mesh have good electrical conductivity and corrosion resistance and are ideal surface electrode materials. The porous structure can increase the contact area between the electrode and the electrolyte and improve the electrochemical performance of the battery. When selecting, factors such as the purity, porosity, and thickness of the material need to be comprehensively considered to ensure that the performance of the electrode meets the requirements of the battery. The preparation of the porous copper foil can adopt methods such as electrochemical deposition, powder metallurgy, or laser drilling. The electrochemical deposition method forms a uniform pore structure on the surface of the copper foil by controlling the current and voltage; the powder metallurgy method mixes copper powder with a pore-forming agent and then presses and forms it, and then obtains a porous structure through sintering treatment; the laser drilling method uses a laser beam to drill holes in the copper foil to form the required pore structure. The preparation of the porous copper mesh can adopt methods such as weaving or stretching to form a mesh structure with a uniform pore structure.

[0069] The prepared porous copper foil or porous copper mesh needs to be subjected to performance evaluation, including tests of indicators such as electrical conductivity, corrosion resistance, and porosity. These tests can ensure that the performance of the electrode meets the requirements of the battery and provide strong support for subsequent battery design and manufacturing. The surface electrode should be arranged at the center position or key area on the surface of the negative electrode to ensure that it can accurately reflect the voltage distribution and changes inside the battery. At the same time, the connection and isolation between the electrode and other parts of the battery also need to be considered to avoid adverse effects on the battery performance. The fixing method of the surface electrode can adopt methods such as welding, bonding, or mechanical fixing. The welding method realizes a firm connection by melting the metal between the electrode and the negative electrode at high temperature; the bonding method uses an adhesive to bond the electrode to the negative electrode; the mechanical fixing method fixes the electrode on the negative electrode through mechanical components such as screws and buckles. When selecting the fixing method, the firmness of the connection, electrical conductivity, and the impact on the battery performance need to be comprehensively considered. After the arrangement and fixing are completed, the surface electrode needs to be inspected and tested to ensure that its connection is firm, the conductivity is good, and it will not have an adverse impact on the battery performance. These inspections can include visual inspection, conductivity test, and corrosion resistance test, etc.

[0070] Step S12: Connect the voltage detection circuit to the surface electrode and the negative electrode. The voltage detection circuit usually consists of components such as high-precision resistors, operational amplifiers, analog-to-digital converters (ADCs), and microcontrollers (MCUs). The high-precision resistor is used for voltage division to reduce the high voltage of the battery to a range acceptable to the ADC; the operational amplifier is used to improve the gain and stability of the circuit; the ADC is used to convert the analog voltage signal into a digital signal for the MCU to process; and the MCU is responsible for receiving the data from the ADC and performing subsequent processing and analysis. When designing the voltage detection circuit, factors such as circuit accuracy, response speed, stability, and power consumption need to be considered. Accuracy determines the measurement accuracy, response speed determines the timeliness of real-time monitoring, and stability determines the reliability of the circuit during long-term operation. At the same time, the power consumption of the circuit also needs to be considered to ensure that it does not have an adverse impact on battery performance. When selecting circuit components, factors such as component performance, price, and reliability need to be comprehensively considered. For example, high-precision resistors should be selected with low temperature coefficients and low noise; operational amplifiers should be selected with high gain, low noise, and low power consumption; ADCs should be selected with high resolution, low power consumption, and fast conversion rates; and MCUs should be selected with high performance, low power consumption, and rich peripherals. After the voltage detection circuit design is completed, it needs to be connected to the surface electrode and the negative electrode. The connection method can be welding, plugging, or wireless connection, etc. The welding method melts the metal between the circuit component and the electrode through high temperature to achieve a firm connection; the plugging method uses components such as plugs and sockets to connect the circuit component and the electrode together; the wireless connection method uses wireless communication technology to transmit data between the circuit component and the electrode. When selecting the connection method, factors such as connection firmness, conductivity, maintainability, and impact on battery performance need to be comprehensively considered. After establishing the connection method, the connection needs to be optimized to improve the reliability and stability of the connection. For example, the redundant connection method can be adopted, that is, increasing multiple connection points to improve the connection firmness; anti-loosening measures can also be adopted, such as using locking screws or buckles and other components to prevent the connection from loosening. In addition, the anti-interference of the connection also needs to be considered to avoid the impact of external interference on the measurement accuracy. After the connection establishment and optimization are completed, the connection needs to be inspected and tested to ensure that it is firmly connected, has good conductivity, and does not have an adverse impact on battery performance. These inspections can include visual inspection, conductivity test, and stability test, etc.

[0071] Step S13: During the charging process of the lithium battery, use a voltage detection circuit to detect the voltage between the surface electrode and the negative electrode to ensure that the voltage difference between the surface electrode and the negative electrode of the battery can be measured. During the charging process of the lithium battery, it is necessary to use a voltage detection circuit to monitor the voltage between the surface electrode and the negative electrode in real time. The monitoring frequency should be determined according to the charging characteristics of the battery and the required measurement accuracy. Generally speaking, the higher the monitoring frequency, the better the measurement accuracy and real-time performance. However, too high a monitoring frequency will also increase the power consumption and data processing volume of the system. Therefore, it is necessary to select an appropriate monitoring frequency on the premise of ensuring measurement accuracy and real-time performance. During the real-time monitoring process, it is necessary to process and analyze the collected voltage data. The processing process can include steps such as filtering, denoising, and calibration to improve the accuracy and reliability of the measurement. At the same time, it is also necessary to store and record the processed data for subsequent analysis and diagnosis. During the real-time monitoring process, if an abnormal voltage or a voltage exceeding the preset threshold is detected, the alarm mechanism should be triggered immediately, and corresponding protection measures should be taken. For example, the charging power supply can be cut off or the charging current can be reduced to avoid overcharging of the battery or other safety accidents. Based on the real-time monitoring of the voltage between the surface electrode and the negative electrode, it is necessary to calculate and analyze the voltage difference.

[0072] The calculation method of the voltage difference can adopt a simple subtraction operation, that is, subtracting the voltage of the negative electrode from the voltage of the surface electrode. During the calculation process, it is necessary to pay attention to the consistency of the voltage reference point and unit to ensure the accuracy of the calculation result. After obtaining the voltage difference, it is necessary to further analyze and process it. The analysis process can include steps such as trend analysis, anomaly detection, and fault diagnosis. Through trend analysis, the change of the voltage difference with the charging time can be understood; through anomaly detection, the abnormal situation of the voltage difference can be found in time; through fault diagnosis, it can be judged whether there are faults or safety hazards in the battery. The measurement and analysis results of the voltage difference can be applied to the management and control of the battery. For example, the charging strategy can be adjusted according to the change of the voltage difference to optimize the charging efficiency and safety of the battery; the analysis results can also be fed back to the battery manufacturer or R & D team for improvement and optimization of the battery design and manufacturing.

[0073] Furthermore, in this embodiment, before the step of calculating the lithium plating current of the battery according to the voltage difference, the following steps are further included:

[0074] Perform a fast charging test on the battery while monitoring the voltage difference and the total charging current;

[0075] Record the change of the voltage difference and determine the time point when the lithium plating phenomenon of the battery starts.

[0076] Specifically, in this embodiment, monitoring the battery state by measuring the voltage difference and further calculating the lithium plating current is a complex but important process. The following are the detailed steps and explanations for performing a fast charge test, monitoring the voltage difference and the total charging current, and recording the change of the voltage difference to determine the starting time point of the lithium plating phenomenon in the battery before calculating the lithium plating current of the battery based on the voltage difference:

[0077] Ensure the use of high-precision current and voltage measuring instruments to guarantee the accuracy and reliability of the data. Conduct the test in a laboratory environment with constant temperature and humidity to eliminate the influence of external factors on the test results. Record the battery's power and voltage in the initial state to ensure that the battery is within the normal operating range. Check the connection status of the battery to ensure that the connection between the voltage detection circuit and the surface electrode and the negative electrode is firm and has good conductivity. Use professional equipment to quickly charge the battery. During the charging process, monitor the voltage difference (i.e., the voltage difference between the surface electrode and the negative electrode) and the total charging current in real time.

[0078] Analyze the change trend of the voltage difference to judge the polarization degree and impedance change inside the battery. Monitor the change of the voltage difference during the fast charge process. When the voltage difference rises sharply, this may indicate that lithium plating has occurred inside the battery. Determine the starting time point of the lithium plating phenomenon in the battery according to the change of the voltage difference. This time point is of great significance for subsequent analysis of battery performance, optimization of the charging strategy, and prevention of battery safety accidents. After determining the starting time point of the lithium plating phenomenon in the battery, the lithium plating current can be further calculated based on the voltage difference and the internal parameters of the battery (such as internal resistance, polarization voltage, etc.). This step requires the use of more complex electrochemical models and algorithms to accurately evaluate the lithium plating situation of the battery. When performing the fast charge test, ensure the safety performance of the battery to prevent safety accidents caused by safety hazards such as battery overheating and overload. Use high-precision measuring instruments and professional data analysis software to ensure the accuracy and reliability of the data. To improve the reliability of the experimental results, it is recommended to conduct multiple repeated experiments and take the average value as the final result. During the experiment, continuously monitor the battery state, including parameters such as power, voltage, and temperature, to ensure that the battery is within the normal operating range.

[0079] Furthermore, in this embodiment, the step of recording the change of the voltage difference and determining the starting time point of the lithium plating phenomenon in the battery further includes:

[0080] Combined with the charging current and charging time of the battery, calculate the current SOC value of the battery;

[0081] When the voltage difference starts to show an incremental change, determine the critical SOC value corresponding to the occurrence of surface lithium plating in the battery;

[0082] Determine the starting time point of the lithium plating phenomenon of the battery according to the critical SOC value corresponding to the occurrence of surface lithium plating of the battery.

[0083] Specifically, in this embodiment, in the step of recording the change of the voltage difference to determine the starting time point of the lithium plating phenomenon of the battery, by combining the charging current, charging time, and SOC (State of Charge, that is, the battery power) value of the battery, the starting time point of the lithium plating phenomenon of the battery can be determined more accurately. The following are the detailed steps and descriptions:

[0084] Calculate the current SOC value, and record the charging current and charging time of the battery in real time. Use the rated capacity (Ah) of the battery, the real-time recorded charging current (A), and charging time (h), and calculate the current charged power of the battery by integrating or accumulating. Divide the charged power by the rated capacity of the battery to obtain the current SOC value of the battery.

[0085] During the charging process, continuously monitor the change of the voltage difference (that is, the voltage difference between the surface electrode of the battery and the negative electrode). When the voltage difference starts to show an obvious incremental change, this usually means that some abnormal reactions start to occur inside the battery, such as the lithium plating phenomenon. Record the SOC value corresponding to when the voltage difference starts to show an incremental change as the critical SOC value. This value represents the threshold at which the battery starts to have surface lithium plating during the charging process. According to the recorded critical SOC value, trace back to the time point when this SOC value is reached during the charging process. Determine the time point when the critical SOC value is reached as the starting time point of the lithium plating phenomenon of the battery. Ensure that the measurement data of the charging current, charging time, and voltage difference are accurate to improve the accuracy of the calculation of the SOC value and the critical SOC value. To improve the reliability of the experimental results, it is recommended to conduct multiple repeated experiments and take the average value as the final result. During the experiment, continuously monitor the state of the battery, including parameters such as power, voltage, and temperature, to ensure that the battery is within the normal working range.

[0086] Based on the first embodiment and / or the second embodiment of the present application, in the third embodiment of the present application, the same or similar content as in the above-mentioned first embodiment and second embodiment can be referred to the above introduction and will not be repeated hereinafter. On this basis, please refer to Figure 3 . In this embodiment, step S20, the step of calculating the lithium plating current of the battery according to the voltage difference, includes;

[0087] Step S21, record the increase amount of the voltage difference and the total electron resistance of graphite according to the starting time of the surface lithium plating of the battery;

[0088] Step S22, calculate the lithium plating current according to the increase amount of the voltage difference and the total electron resistance of graphite.

[0089] Specifically, in this embodiment, by measuring the increase in the voltage difference of the battery and the total electronic resistance of the graphite, and establishing a relationship model between the voltage difference and the lithium plating current, the magnitude of the lithium plating current when the battery exhibits lithium plating can be calculated. This method is of great significance for understanding the chemical reaction state inside the battery and the migration of lithium ions, and can provide strong support for the research, production, and use of lithium-ion batteries. The following are the detailed steps and explanations:

[0090] Step S21: According to the starting time of surface lithium plating in the battery, record the increase in the voltage difference and the total electronic resistance of the graphite. Through experimental observation or data analysis, determine the time point when lithium plating begins to occur during the charging process of the battery. This time point can be inferred by monitoring the changes in parameters such as the voltage, current, and temperature of the battery.

[0091] For example, methods such as the voltage differential method and the static voltage method can be used to detect the lithium plating behavior of the negative electrode. These methods can judge whether the battery has lithium plating by analyzing the voltage curve, voltage differential curve, etc. of the battery. After the battery exhibits lithium plating, continue to monitor the change in the voltage difference of the battery. Record the increase in the voltage difference over time starting from the lithium plating starting time. The increase in the voltage difference can reflect the intensity of the chemical reaction inside the battery and the migration of lithium ions. If the voltage difference increases rapidly, it may indicate that the chemical reaction inside the battery is relatively intense and the migration speed of lithium ions is relatively fast. As the main component of the negative electrode of a lithium-ion battery, the electronic resistance of graphite has an important impact on the battery performance. After the battery exhibits lithium plating, it is necessary to measure the total electronic resistance of the graphite. The electronic resistance of graphite can be measured by methods such as electrochemical impedance spectroscopy (EIS). EIS is a non-destructive electrochemical testing technique that can measure parameters such as the impedance and capacitance of various parts inside the battery. By measuring the electronic resistance of graphite, the electron transfer situation inside the battery and the performance state of graphite can be understood.

[0092] Step S22: Calculate the lithium plating current based on the increase in voltage difference and the total electron resistance of graphite. To calculate the lithium plating current, a relationship model between the voltage difference and the lithium plating current needs to be established. This model can be established through methods such as theoretical analysis and fitting of experimental data. Theoretically, there is a certain relationship between the voltage difference and the lithium plating current. When lithium plating occurs in the battery, the migration of lithium ions will cause a redistribution of charges inside the battery, thus forming a voltage difference. At the same time, the magnitude of the lithium plating current will also affect the migration speed of lithium ions and the change in voltage difference. Therefore, a mathematical model can be established to describe this relationship. After establishing the relationship model between the voltage difference and the lithium plating current, the actually measured increase in voltage difference and the total electron resistance of graphite can be substituted into the model for calculation. Through calculation, the magnitude of the lithium plating current when lithium plating occurs in the battery can be obtained. This current value can reflect the migration speed of lithium ions inside the battery and the severity of the lithium plating phenomenon. To verify the accuracy of the calculation results, other methods can be used for comparison and verification. For example, the severity of the lithium plating phenomenon can be indirectly evaluated by measuring parameters such as the capacity attenuation and internal resistance change of the battery, and compared with the calculation results. If the calculation results are consistent with the actual situation, it indicates that the established relationship model between the voltage difference and the lithium plating current is accurate and can be used for subsequent experiments and analyses.

[0093] It should be particularly noted that the increase in voltage difference is affected by various factors, including the charging rate of the battery, temperature, battery capacity, and the chemical reaction state inside the battery, etc.

[0094] The faster the charging rate, the more intense the chemical reaction inside the battery, the faster the migration speed of lithium ions, and the greater the possible increase in voltage difference.

[0095] Temperature affects both the chemical reaction rate inside the battery and the migration speed of lithium ions. Generally, the higher the temperature, the faster the chemical reaction rate, the faster the migration speed of lithium ions, and the greater the possible increase in voltage difference.

[0096] The larger the battery capacity, the more complex the chemical reaction inside the battery, and the more difficult the migration and storage of lithium ions. Therefore, the increase in voltage difference may also be greater.

[0097] The chemical reaction state inside the battery also has an important impact on the increase in voltage difference. For example, when lithium plating occurs in the battery, the chemical reaction inside the battery will become more intense, and the migration speed of lithium ions will also increase, resulting in an increase in the increase in voltage difference.

[0098] Based on the first embodiment and / or the second embodiment and / or the third embodiment of the present application, in the fourth embodiment of the present application, the content that is the same as or similar to the above-mentioned embodiment one, embodiment two, and embodiment three can be referred to the above introduction and will not be repeated hereinafter. On this basis, please refer toFigure 4 。In this embodiment, step S30, the step of obtaining the lithium deposition capacity of the battery according to the integral of the lithium deposition current with respect to time, includes:

[0099] Step S31, determining an integration interval according to the start time point and the end time when the lithium deposition phenomenon starts to occur;

[0100] Step S32, integrating the lithium deposition current within the determined integration interval to obtain the lithium deposition capacity of the battery.

[0101] Specifically, in this embodiment, the process of obtaining the lithium deposition capacity of the battery according to the integral of the lithium deposition current with respect to time is mainly based on the principle of the current integration method. That is, by integrating the lithium deposition current with respect to time, the total amount of lithium deposited in the battery within a specific time period can be calculated. This method is of great significance for quantifying the lithium deposition phenomenon of the battery, evaluating the health status of the battery, and optimizing the charge and discharge strategy of the battery. The following are the detailed steps and explanations:

[0102] Step S31: Determine the integration interval. The integration interval is a key parameter in the current integration method, which determines the time range for integrating the lithium deposition current. In step S31, we need to determine this interval according to the start time point and the end time when the lithium deposition phenomenon starts to occur. To accurately identify the start and end time points of the lithium deposition phenomenon, it is usually necessary to rely on the battery management system (BMS) or other professional battery monitoring devices. These devices can monitor parameters such as the voltage, current, and temperature of the battery in real time, and identify the occurrence of the lithium deposition phenomenon through algorithm analysis. The start time point of the lithium deposition phenomenon is usually closely related to the charging process of the battery. When the battery is charged to a certain specific voltage or current threshold, lithium ions may start to be unable to be smoothly embedded in the negative electrode, thus triggering the lithium deposition phenomenon. Therefore, we can monitor the charging process of the battery and combine the voltage change increment of the battery to identify the start time point of the lithium deposition phenomenon.

[0103] The end time point of the lithium plating phenomenon is relatively difficult to determine because it may be affected by various factors, such as the charge-discharge strategy of the battery, temperature, and the internal structure of the battery. However, we can roughly judge the end of the lithium plating phenomenon by observing the stability of parameters such as the voltage and current of the battery. When these parameters remain stable within a certain period of time, we can consider that the lithium plating phenomenon has ended. When determining the integration interval, we need to consider various factors comprehensively to ensure the accuracy and reliability of the integration. Based on the historical data and charge-discharge strategy of the battery, we can roughly determine the time period when the lithium plating phenomenon may occur according to experience and use it as the integration interval. This method is simple and easy to implement, but there may be certain errors. By real-time monitoring parameters such as the voltage and current of the battery and combining algorithm analysis to dynamically determine the integration interval. This method can more accurately reflect the actual occurrence of the lithium plating phenomenon, but continuous monitoring and analysis of the battery are required. Under laboratory conditions, determine the integration interval by simulating the charge-discharge process of the battery and observing the occurrence of the lithium plating phenomenon. This method can more accurately determine the integration interval, but the cost is high and the operation is complex.

[0104] Step S32: Integrate the lithium plating current. The current integration method is a commonly used method for calculating the amount of electricity. It calculates the amount of electricity discharged or charged by the battery within a specific time period by integrating the current over time. Similarly, we can also calculate the total amount of lithium deposited by the battery within a specific time period by integrating the lithium plating current over time. When integrating the lithium plating current, we need to select a suitable integration method to ensure the accuracy and efficiency of the integration. Solve the integral value by numerical calculation methods. This method is applicable to complex current change functions and long integration intervals. Common numerical integration methods include the trapezoidal method, Simpson's method, etc. When the current change function has a clear mathematical expression, we can solve the integral value by analytical methods. This method is usually more accurate and has higher calculation efficiency.

[0105] To accurately calculate the integral value, we need to perform high-precision data sampling on the lithium plating current. The sampling frequency should be high enough to capture the rapid changes in the current. According to the characteristics of the lithium plating phenomenon and the charge-discharge strategy of the battery, we can divide the integration interval into multiple sub-intervals and integrate each sub-interval separately. This helps to improve the accuracy and efficiency of the integration. During the integration process, we need to perform error analysis on the integration result to evaluate its accuracy. This can be achieved by comparing the results of different integration methods, analyzing sampling errors and integration errors, etc.

[0106] To ensure the accuracy and reliability of the integration results, we need to verify them. The accuracy of the integration results is verified through battery charge and discharge experiments under laboratory conditions. This can be achieved by comparing the measured lithium deposition capacity with the lithium deposition capacity calculated by integration. The rationality of the integration results is verified based on the electrochemical principles and mathematical models of the battery. This can be achieved by analyzing the changes in parameters such as the voltage and current of the battery and the internal structure of the battery. The data used in the integration process is verified to ensure its accuracy and integrity. This can be achieved by checking the data acquisition, processing, and storage processes.

[0107] Other embodiments or specific implementation manners of the battery design device for lithium deposition current and lithium deposition amount in this application can refer to the above method embodiments, which will not be elaborated here.

[0108] It should be noted that in this article, the terms "including", "comprising", or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or system including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article, or system. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of another identical element in the process, method, article, or system including that element.

[0109] The serial numbers of the above embodiments of this application are only for description and do not represent the superiority or inferiority of the embodiments.

[0110] Through the description of the above embodiments, those skilled in the art can clearly understand that the above embodiment methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases, the former is a better implementation method. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as a read-only memory / random access memory, magnetic disk, optical disk), and includes several instructions for causing a terminal device (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in various embodiments of this application.

[0111] The above are only the preferred embodiments of this application, and do not limit the patent scope of this application accordingly. Any equivalent structure or equivalent process transformation made by using the specification and drawings of this application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of this application.

Claims

1. A battery design method for lithium plating current and lithium plating amount, characterized in that, The battery design method for the lithium plating current and lithium plating amount includes: During the charging process of the lithium battery, use a voltage detection circuit to measure the voltage difference between the surface electrode of the battery and the negative electrode in real time; Calculate the lithium plating current of the battery according to the voltage difference; Obtain the lithium plating capacity of the battery according to the integral of the lithium plating current with respect to time.

2. The method according to claim 1, wherein The step of using a voltage detection circuit to measure the voltage difference between the surface electrode of the battery and the negative electrode in real time during the charging process of the lithium battery further includes: Arrange a porous copper foil or a porous copper mesh on the surface of the negative electrode as the surface electrode; Establish a connection between the voltage detection circuit, the surface electrode, and the negative electrode; During the charging process of the lithium battery, use the voltage detection circuit to detect the voltage between the surface electrode and the negative electrode to ensure that the voltage difference between the surface electrode of the battery and the negative electrode can be measured.

3. The method according to claim 2, wherein Before the step of calculating the lithium plating current of the battery according to the voltage difference, it further includes: Conduct a fast charging test on the battery while monitoring the voltage difference and the total charging current; Record the change of the voltage difference and determine the starting time point of the lithium plating phenomenon of the battery.

4. The method according to claim 3, characterized in that, The step of recording the change of the voltage difference and determining the starting time point of the lithium plating phenomenon of the battery further includes: Combine the charging current and charging time of the battery to calculate the current SOC value of the battery; When the voltage difference starts to show an incremental change, determine the critical SOC value corresponding to the surface lithium plating of the battery; Determine the starting time point of the lithium plating phenomenon of the battery according to the critical SOC value corresponding to the surface lithium plating of the battery.

5. The method according to claim 4, characterized in that The step of calculating the lithium plating current of the battery according to the voltage difference includes: According to the starting time of the surface lithium plating of the battery, record the increase amount of the voltage difference and the total electron resistance of graphite; Calculate the lithium plating current according to the increase amount of the voltage difference and the total electron resistance of graphite.

6. The method according to claim 5, characterized in that The step of obtaining the lithium plating capacity of the battery according to the integral of the lithium plating current with respect to time includes: Determine the integration interval according to the starting time point and the ending time of the lithium plating phenomenon; Integrate the lithium plating current within the determined integration interval to obtain the lithium plating capacity of the battery.

7. The method according to claim 6, wherein Before the step of using a voltage detection circuit to measure the voltage difference between the surface electrode of the battery and the negative electrode in real time during the charging process of the lithium battery, it includes: Detect the working state of the battery; When the working state of the battery is in a working state without a fault indication, execute the step of using a voltage detection circuit to measure the voltage difference between the surface electrode of the battery and the negative electrode in real time during the charging process of the lithium battery.

8. A battery design device for lithium deposition current and lithium deposition amount, characterized in that, The battery design device for the lithium plating current and lithium plating amount includes: a voltage detection module, a lithium plating current module, and a lithium plating capacity module; The voltage detection module, during the charging process of the lithium battery, uses a voltage detection circuit to measure the voltage difference between the surface electrode of the battery and the negative electrode in real time; The lithium plating current module calculates the lithium plating current of the battery according to the voltage difference; The lithium plating capacity module obtains the lithium plating capacity of the battery according to the integral of the lithium plating current with respect to time.

9. A battery design device for lithium plating current and lithium plating amount, characterized in that, The battery design device for the lithium plating current and lithium plating amount includes: a memory, a processor, and a computer program stored on the memory and executable on the processor. When the computer program is executed by the processor, it implements the steps of the battery design method for the lithium plating current and lithium plating amount according to any one of claims 1 to 7.

10. A computer storage medium, characterized in that, A computer program is stored on the computer storage medium. When the computer program is executed by a processor, it implements the steps of the battery design method for the lithium plating current and lithium plating amount according to any one of claims 1 to 7.

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