A battery temperature monitoring scheme evaluation method and related equipment

Abstract

The present application discloses a battery temperature monitoring scheme evaluation method, device, equipment and readable storage medium, including: generating simulated battery cell internal resistance and current change data according to basic battery cell performance parameters, battery cell power MAP table, evaluation environment temperature and internal resistance growth coefficient; simulating and constructing Q-R curve based on current change data and simulated battery cell internal resistance, and determining the maximum battery cell internal resistance; designing NTC arrangement scheme and heat insulation scheme applied to battery box, and setting abnormal internal resistance battery cell and temperature monitoring scheme; obtaining thermal simulation temperature monitoring results by conducting thermal simulation on battery box according to the whole battery box digital model and vehicle operation conditions; analyzing thermal simulation temperature monitoring results according to battery cell safety performance criteria and BMS over-temperature alarm threshold criteria, and generating rationality evaluation results. The present application not only improves the accuracy and rationality of battery temperature monitoring, but also provides strong support for the design and optimization of battery systems.

Description

Technical Field

[0001] The present application relates to the field of battery simulation, and more specifically, to a battery temperature monitoring scheme evaluation method and related equipment. Background Art

[0002] Battery cell temperature monitoring is a key indicator for evaluating the dynamic performance of battery cells and formulating control strategies, especially when the battery pack contains multiple battery cells. However, in actual engineering applications, due to factors such as the hardware and software conditions of the battery management system (BMS), the layout of the electrical wiring harness, and cost control, it is impossible to install a temperature detector (NTC) sensor on each battery cell to achieve comprehensive dynamic temperature monitoring.

[0003] The existing technical solutions mainly focus on the location of the highest and lowest temperature points in the battery system under normal operating conditions in the NTC arrangement, and use this as the basis for judging the performance of the battery system and the safety design. This design idea believes that as long as the NTC points are arranged in the highest and lowest temperature areas, the design requirements can be met. However, this solution does not take into account the impact of changes in the internal resistance of the battery cell under abnormal conditions, such as micro-short circuits, cold solder joints, leakage, etc. in the battery cell. In particular, when an abnormality occurs in a battery cell at a non-NTC point, whether the over-temperature alarm can be triggered in time to ensure the safety of the entire battery system.

[0004] In addition, in the actual thermal runaway insulation design of the battery system, in order to save costs, the thickness and even material of the insulation materials inside different battery modules may be different, and not every battery cell must be separated by insulation materials. Different designs will affect the heat conduction of the battery cell in the thickness direction, so that when a battery cell is abnormal, its heat conduction effect on the adjacent battery cells varies due to different insulation schemes. In particular, when an abnormality or even thermal runaway occurs at a non-NTC position, the insulation material with low thermal conductivity and large thickness will hinder the conduction of heat along the thickness direction of the battery cell, resulting in the temperature data of the adjacent NTC position unable to reflect significant changes in a timely manner, thereby increasing the safety risk of the battery system.

[0005] In summary, the existing evaluation methods are still insufficient in evaluating the rationality of battery temperature monitoring solutions. Summary of the invention

[0006] In view of this, the present application provides a battery temperature monitoring scheme evaluation method, device, equipment and readable storage medium, which comprehensively considers the characteristics of the thermal runaway insulation scheme between battery cells, the change of internal resistance under abnormal conditions, the performance parameters of the battery cells under different operating conditions, and the insulation characteristics of the built-in materials of the battery cells. It not only improves the accuracy and rationality of battery temperature monitoring, but also provides strong support for the design and optimization of battery systems.

[0007] In a first aspect, the present application provides a battery temperature monitoring scheme evaluation method, comprising:

[0008] Generate simulated cell internal resistance and current change data based on the basic cell performance parameters, cell power MAP table, assessed ambient temperature, and preset internal resistance growth coefficient;

[0009] Based on the current change data and the simulated battery cell internal resistance, a QR curve is simulated to characterize the relationship between the battery cell heating value and the internal resistance change under different working conditions, and the maximum battery cell internal resistance is determined;

[0010] Design an NTC arrangement scheme and a heat insulation scheme for the battery box, and set an abnormal internal resistance battery cell and a temperature monitoring scheme, wherein the NTCs are evenly spaced along the battery cell arrangement position, and the abnormal internal resistance battery cell is any battery cell between two NTCs;

[0011] According to the digital model of the battery box and the operating conditions of the whole vehicle, a thermal simulation is performed on the battery box by setting the abnormal internal resistance battery cell to the maximum battery cell internal resistance to obtain a thermal simulation temperature monitoring result;

[0012] The thermal simulation temperature monitoring result is analyzed according to the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion to generate a rationality evaluation result of the temperature monitoring scheme.

[0013] Optionally, based on the basic parameters of the battery performance, the battery power MAP table, the evaluation environment temperature and the preset internal resistance growth coefficient, simulated battery internal resistance and current change data are generated, including:

[0014] Generate the cell internal resistance calculation benchmark data based on the basic cell performance parameters, the evaluation ambient temperature, and the system power MAP table converted from the cell power MAP table;

[0015] Determine the simulated cell internal resistance according to the cell internal resistance initial value in the cell internal resistance calculation benchmark data and a preset internal resistance growth coefficient;

[0016] According to the temperature power threshold parameter in the battery cell internal resistance calculation benchmark data, combined with the simulated battery cell internal resistance, the current accompanying power change relationship is determined, and current change data is generated.

[0017] Optionally, based on the basic parameters of the battery cell performance, the evaluation ambient temperature, and the system power MAP table converted from the battery cell power MAP table, the battery cell internal resistance calculation benchmark data is generated, including:

[0018] Based on the basic performance parameters of the battery cells, determine the internal resistance performance parameters, open circuit voltage performance parameters and initial value of the internal resistance of the battery cells at the same temperature and charge state;

[0019] The cell power MAP table is converted into a system power MAP table according to the correlation between the cell level power and the system level power, and the temperature power threshold parameter is defined in combination with the internal resistance performance parameter, the open circuit voltage performance parameter and the evaluation ambient temperature;

[0020] The battery cell internal resistance initial value and the temperature power threshold parameter are integrated to generate battery cell internal resistance calculation benchmark data.

[0021] Optionally, the current and power change relationship is:

[0022]

[0023] Among them, OCV is the open circuit voltage performance parameter; R is the simulated battery cell internal resistance; P is the temperature power threshold parameter.

[0024] Optionally, the correlation between the cell level power and the system level power is:

[0025]

[0026] in, The power of a single battery cell at the system level; is the average power value at the cell level; is the temperature; ζ is the energy conversion coefficient, which is between 0.8 and 0.95; T is the ambient temperature or the cell temperature; SOC is the kneading function, which takes the average value of the cell state of charge.

[0027] Optionally, the thermal simulation temperature monitoring result is analyzed according to a preset battery cell safety performance criterion and a BMS over-temperature alarm threshold criterion to generate a rationality evaluation result of the temperature monitoring scheme, including:

[0028] If the thermal simulation temperature monitoring result can simultaneously meet the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion requirement, then the rationality evaluation result of the temperature monitoring scheme is determined to be a reasonable setting;

[0029] If the thermal simulation temperature monitoring result cannot simultaneously meet the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion requirements, the rationality evaluation result of the temperature monitoring scheme is determined to be unreasonable, and the temperature monitoring scheme is optimized.

[0030] Optionally, the safety performance criterion of the battery cell is that the maximum built-in temperature of the battery cell with abnormal internal resistance obtained by simulation under vehicle working conditions is lower than the closed-cell temperature of the thermal insulation material;

[0031] The BMS over-temperature alarm threshold judgment criterion is that the adjacent NTC monitoring value of the abnormal internal resistance battery cell reaches the BMS alarm setting threshold.

[0032] In a second aspect, the present application also provides a battery temperature monitoring scheme evaluation device, comprising:

[0033] The basic parameter unit is used to generate simulated cell internal resistance and current change data according to the basic parameters of cell performance, cell power MAP table, evaluation ambient temperature and preset internal resistance growth coefficient;

[0034] A relationship curve unit, for simulating and constructing a QR curve representing the relationship between the heating value and the internal resistance change of the battery cell under different working conditions based on the current change data and the simulated battery cell internal resistance, and determining the maximum battery cell internal resistance;

[0035] A scheme design unit is used to design an NTC arrangement scheme and a heat insulation scheme for the battery box, and set an abnormal internal resistance battery cell and a temperature monitoring scheme, wherein the NTCs are evenly spaced along the battery cell arrangement position, and the abnormal internal resistance battery cell is any battery cell between two NTCs;

[0036] A simulation monitoring unit is used to perform thermal simulation on the battery box according to the digital model of the battery box and the operating condition of the whole vehicle by setting the abnormal internal resistance battery cell to the maximum battery cell internal resistance to obtain a thermal simulation temperature monitoring result;

[0037] The analysis and evaluation unit is used to analyze the thermal simulation temperature monitoring result according to the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion, and generate a rationality evaluation result of the temperature monitoring scheme.

[0038] In a third aspect, the present application also provides a battery temperature monitoring solution evaluation device, including a memory and a processor;

[0039] The memory is used to store programs;

[0040] The processor is used to execute the program to implement each step of the battery temperature monitoring solution evaluation method as described in any one of the above items.

[0041] A readable storage medium having a computer program stored thereon, characterized in that when the computer program is executed by a processor, each step of the battery temperature monitoring scheme evaluation method as described in any one of the above items is implemented.

[0042] It can be seen from the above technical solutions that the embodiments of the present application provide a battery temperature monitoring solution evaluation method, device, equipment and readable storage medium. When evaluating the battery temperature monitoring solution, the present application not only considers the performance of the battery cell under normal operating conditions, but also introduces the battery cell internal resistance increase coefficient to simulate the change in internal resistance of the battery cell under abnormal conditions. This enables the present application to more accurately evaluate the temperature monitoring needs of the battery cell when facing increased internal resistance or internal safety risks. The simulated battery cell internal resistance and current change data are calculated based on the battery cell's own performance parameters, and a QR curve is constructed to characterize the relationship between the battery cell's heat generation and internal resistance change under different operating conditions, and the maximum battery cell internal resistance is determined, which can better reflect the changes in the battery cell in actual use, thereby improving the accuracy and rationality of the evaluation.

[0043] Secondly, during the evaluation process, this application fully considered the impact of different insulation schemes on the temperature monitoring of the battery system. By designing the NTC arrangement scheme and insulation scheme applied to the battery box, and setting the abnormal internal resistance battery cells and temperature monitoring scheme, this application can evaluate the impact of different insulation material thicknesses, materials, and spacing arrangements on heat conduction between battery cells. At the same time, thermal simulation is performed in combination with the digital model of the battery box and the operating conditions of the whole vehicle to simulate the temperature changes of the battery cells under different insulation schemes, so as to more accurately evaluate the rationality of the temperature monitoring scheme.

[0044] In addition, by setting the location and number of abnormal internal resistance cells, the present invention can timely discover and optimize the safety weaknesses of the battery system during the development and design stage. At the same time, combined with the preset cell safety performance criteria and the BMS over-temperature alarm threshold criteria, it can analyze the thermal simulation temperature monitoring results and generate a rationality evaluation result for the temperature monitoring scheme, providing strong support for the design and optimization of the battery system. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0046] Figure 1 A schematic diagram of calculation parameters of abnormal battery cell heat generation disclosed in an embodiment of the present application;

[0047] Figure 2 A flowchart of a battery temperature monitoring solution evaluation method disclosed in an embodiment of the present application;

[0048] Figure 3A QR curve diagram of a maximum charging power at a high temperature of 45°C disclosed in an embodiment of the present application;

[0049] Figure 4 A QR curve diagram of a maximum charging power at a high temperature of 35°C disclosed in an embodiment of the present application;

[0050] Figure 5 A schematic diagram of an NTC arrangement scheme disclosed in an embodiment of the present application;

[0051] Figure 6 A schematic diagram of another NTC arrangement scheme disclosed in an embodiment of the present application;

[0052] Figure 7 A schematic diagram of a battery temperature monitoring scheme evaluation device disclosed in an embodiment of the present application;

[0053] Figure 8 This is a hardware structure block diagram of a battery temperature monitoring solution evaluation device disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0055] The present application can be used in many general or special computing device environments or configurations, such as personal computers, server computers, handheld or portable devices, tablet devices, multi-processor devices, distributed computing environments including any of the above devices or equipment, etc.

[0056] An embodiment of the present application provides a battery temperature monitoring scheme evaluation method, which can be applied to various systems or platforms involving battery temperature monitoring management or design testing, and can also be applied to various computer terminals or smart terminals. The execution subject can be a processor or server of the computer terminal or smart terminal.

[0057] Before introducing the solution of this application, the implementation principle of this application is first introduced.

[0058] According to the performance and usage strategy of lithium batteries, during the use of the battery system, especially in the early stage of life or when the internal resistance of the battery cell is in a normal state, the system design usually reserves a safety margin to ensure stable operation. At this stage, the maximum voltage Umax and minimum voltage Umin of the battery cell's open circuit voltage (CCV) in the working state, as well as the maximum power Pmax of charging and discharging can all remain constant.

[0059] However, as the battery life increases or the internal resistance of the battery increases to a certain critical value due to abnormal phenomena such as internal short circuit, poor soldering, leakage, etc., that is, the maximum internal resistance of the battery in this application, the voltage limit and charging power of the battery will be limited. Figure 1 As shown in the figure, during this stage, the heat generation Q of the battery cell will reach its maximum value. Subsequently, due to power limitation, the charge and discharge current will also decrease, the energy consumption of the battery itself will increase, the internal friction will increase, and the battery management system (BMS) will take measures to avoid reaching the lower limit voltage, which will further lead to power limitation. With these changes, the heat generation Q of the battery cell itself will gradually decrease. It is worth noting that the occurrence of the maximum battery cell internal resistance may be an accidental occurrence.

[0060] Based on the usage characteristics of the above-mentioned batteries, when the heat generated by the abnormal battery cell reaches the maximum value, that is, its own heat generation increases significantly, the rationality of the temperature alarm threshold setting of the battery system and the appropriateness of the NTC (negative temperature coefficient thermistor) layout of the monitoring point can be evaluated based on the system design plan (including the battery cell insulation plan and NTC arrangement plan).

[0061] Next, the present application scheme is introduced. The present application proposes the following technical scheme, please see below for details.

[0062] Figure 2 This is a flow chart of a battery temperature monitoring solution evaluation method disclosed in an embodiment of the present application.

[0063] like Figure 2 As shown, the method may include:

[0064] Step S1, generating simulated cell internal resistance and current change data according to the basic cell performance parameters, the cell power MAP table, the assessed ambient temperature and the preset internal resistance growth coefficient.

[0065] Specifically, first of all, based on the basic performance parameters of the battery cell, these parameters include the internal resistance and open circuit voltage at different temperatures and charge states. These key data are usually obtained by measuring the battery cell, which provides a basis for calculating the limiting internal resistance (Rlimit) of the battery cell. Considering that the battery system is composed of multiple battery cell units and their related electrical components connected in series and parallel, there are consistency differences in the production and manufacturing process between the battery cells, and the system energy dissipation caused by the size of electrical components and welding when the battery cells are connected in series and parallel, it is necessary to calculate and convert the system-level system power MAP table based on the battery cell's charge and discharge power limit MAP table at different temperatures and SOCs (i.e., the battery cell power MAP table), that is, the power parameters at different temperatures and SOCs.

[0066] In addition, considering that the change range of the internal resistance DCR of the battery cell during practical use or under internal abnormal conditions is difficult to predict, the internal resistance R0 of the battery cell in the initial state is used as the internal resistance reference value, and the R value growth coefficient, i.e. the internal resistance growth coefficient, is introduced to simulate the gradual increase of the internal resistance of the battery cell, and generate the simulated battery cell internal resistance, which helps to more accurately predict the performance and temperature changes of the battery cell during actual use. The smaller the internal resistance growth coefficient, the higher the accuracy of the simulated battery cell internal resistance increase, which is generally 0.001~0.1.

[0067] Since the power values ​​of the battery cells at different temperatures and SOCs are different, in order to evaluate the heat generation of the battery cells and their temperature monitoring values ​​under harsh working conditions, it is necessary to select an appropriate power threshold based on the evaluation ambient temperature. Under high temperature conditions, in order to be more conservative and safe in evaluation, the maximum power threshold (that is, the power value when the battery cell power is not limited at high temperature) can be selected as the temperature power threshold parameter under charge / discharge conditions. The temperature power threshold parameter is combined with the simulated battery cell internal resistance, and according to the basic principles of electrochemistry, current change data can be further generated.

[0068] Step S2: Based on the current change data and the simulated battery cell internal resistance, a QR curve is simulated to characterize the relationship between the battery cell heating value and the internal resistance change under different working conditions, and the maximum battery cell internal resistance is determined.

[0069] Specifically, based on the current change data generated in step S1 and the simulated cell internal resistance, a QR curve representing the relationship between the cell heating value and the internal resistance change under different working conditions can be constructed, and the maximum cell internal resistance Rmax can be determined. In this process, the current change data I and the simulated cell internal resistance R obtained in step S1 are used as input parameters. For a single cell, the cell heating value Q can be calculated by the formula: Q=I²*R.

[0070] By calculating the cell heat value Q under different working conditions (such as different temperatures, different SOCs, different charge and discharge rates, etc.), a series of corresponding cell internal resistance R values ​​can be obtained. Plotting these data points on a coordinate system, with the cell internal resistance R as the horizontal coordinate and the cell heat value Q as the vertical coordinate, you can get the QR curve, which intuitively shows the heating of the cell under different internal resistances. At this point, by analyzing the QR curve, you can determine the maximum cell internal resistance Rmax under given working conditions. Figure 3 and Figure 4 Shown are two QR curves under the conditions of maximum charging power at 45°C and maximum charging power at 35°C. The maximum cell internal resistance Rmax corresponding to the maximum charging power at 45°C is 1.29mΩ, and the maximum cell internal resistance Rmax corresponding to the maximum charging power at 35°C is 1.51mΩ.

[0071] Step S3: designing the NTC arrangement scheme and thermal insulation scheme for the battery box, and setting the abnormal internal resistance cell and temperature monitoring scheme.

[0072] Specifically, this application designs the NTC (negative temperature coefficient thermistor) arrangement and insulation scheme in the battery box, and sets up a temperature monitoring scheme for cells with abnormal internal resistance. In the specific implementation, the NTCs are evenly spaced along the cell arrangement position to ensure comprehensive monitoring of the temperature in the battery box. At the same time, the cell with abnormal internal resistance is set as any cell between two NTCs. This layout allows the abnormal cell to be quickly captured by the adjacent NTC to detect the temperature change signal.

[0073] When designing the NTC arrangement and insulation scheme, it is necessary to determine the location of abnormal internal resistance of the battery cell under harsh conditions and the preliminary scheme for temperature monitoring based on the specific structure of the battery box. Among them, the selection of the thickness of the thermal cotton between the battery cells is a key factor. Usually, the thickness of the thermal insulation cotton is fixed, such as 1mm, but it can also be adjusted appropriately according to the different structural requirements of the battery box. It is worth noting that the thicker the thermal insulation cotton, the greater its thermal resistance in the thickness direction. Under the condition of a certain charge and discharge current, the heat generated by the abnormal battery cell will be relatively large, and the transfer of heat from the abnormal battery cell to the normal battery cell will be hindered to a certain extent. Therefore, in order to obtain more stringent battery cell heat transfer and temperature rise evaluation results, the battery cell module area covered by thicker thermal insulation cotton is usually selected as the evaluation object to ensure the rationality of the design. The design principle is that the greater the thermal resistance between the abnormal battery cell and the normal battery cell, the better, that is, the more difficult it is to detect, the better, which can be adjusted by adjusting the foam and / or increasing the NTC.

[0074] In addition, the design of the thermal insulation scheme between cells must also follow certain principles. If the thermal insulation cotton between cells is arranged every 2 or more cells, then there must be thermal insulation cotton between the NTC monitoring position cell and the abnormal cell to reduce the interference of heat transfer on the temperature monitoring results. When selecting the abnormal cell position, it needs to be determined according to the arrangement of the NTC, and it is usually preferred to be in the middle of the interval cell. Figure 5 and Figure 6 In the arrangement shown, if the NTC is separated by 4 cells, any of the middle cells is selected as a potential abnormal cell; if the NTC is separated by 5 or 6 cells, a middle cell is also selected as the monitoring object. Such a layout and selection principle can maximize the accuracy and reliability of temperature monitoring and provide a strong guarantee for the safe operation of the battery system.

[0075] Step S4: According to the digital model of the battery box and the operating condition of the whole vehicle, a thermal simulation is performed on the battery box by setting the abnormal internal resistance battery cell to the maximum battery cell internal resistance to obtain a thermal simulation temperature monitoring result.

[0076] Specifically, based on the battery box digital model and various working conditions of the vehicle in actual operation, the battery box thermal simulation is carried out by setting an abnormal cell with maximum internal resistance (Rmax). The implementation of this step first depends on the selection of abnormal cells with internal resistance and the determination of the temperature monitoring scheme, and on this basis, the temperature change of abnormal cells under specific working conditions and the response of the monitoring point NTC (negative temperature coefficient thermistor) are predicted.

[0077] In thermal simulation design, the number and thickness of thermal insulation cotton and the position of NTC are all parameters that can be optimized. Generally speaking, thermal insulation cotton is laid between any two adjacent battery cells to reduce heat transfer, but it is also possible to consider setting thermal insulation cotton between multiple battery cells based on actual conditions, such as cost, weight and other factors. Such design flexibility helps us find the best insulation solution.

[0078] During the simulation, the maximum cell internal resistance is assigned to the set abnormal cell, while the internal resistance of other cells remains normal. The cutoff condition of the simulation is that the maximum temperature of the abnormal cell reaches the diaphragm closed-cell temperature threshold, or the temperature of the NTC monitoring point reaches the alarm threshold set by the battery management system (BMS), at which time it is considered that thermal runaway is about to occur. By simulating the charging and discharging process, it can be observed that the abnormal cell generates more heat due to the increase in internal resistance, which in turn causes the temperature of the adjacent cells to rise. This process is achieved by calculating the heat generated by the abnormal cell and considering its impact on other cells. After the simulation is completed, the thermal simulation temperature monitoring results are output, which can be the current-temperature (IT) curves of the abnormal cell and normal cell detection points.

[0079] Step S5: analyzing the thermal simulation temperature monitoring result according to the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion, and generating a rationality evaluation result of the temperature monitoring scheme.

[0080] Specifically, the cell safety performance criterion is that the maximum built-in temperature of the abnormal internal resistance cell obtained by simulation under vehicle conditions is lower than the closed-pore temperature of the thermal insulation material. The cell safety performance criterion is based on the mechanism of thermal runaway of the cell and is determined by the key data obtained by simulation under vehicle conditions, especially the maximum internal temperature of the abnormal internal resistance cell. When the thermal stability inside the cell changes, resulting in increased self-heating and possible thermal runaway, the performance of the porous diaphragm material inside the cell will change. This change is usually manifested as shrinkage of the diaphragm, which may cause internal short circuits and pose a serious threat to the safety of the battery system. In order to ensure the safe operation of the battery system, a safety threshold must be set, that is, the maximum built-in temperature of the abnormal cell obtained by simulation under vehicle conditions must be lower than the closed-pore temperature of the thermal insulation material. The closed-pore temperature refers to the temperature point at which the pore structure of the thermal insulation material changes at high temperature, thereby losing its thermal insulation performance. If the maximum temperature of the abnormal cell exceeds this threshold, it means that the thermal insulation material may no longer be able to effectively prevent further heat transfer, thereby increasing the risk of thermal runaway. By meeting the safety performance criteria of the battery cells, it can be ensured that the battery system will not cause safety hazards due to excessive temperatures of abnormal battery cells during operation.

[0081] The BMS over-temperature alarm threshold criterion is that the adjacent NTC monitoring value of the abnormal internal resistance battery cell reaches the BMS alarm setting threshold. This criterion is determined based on the adjacent NTC monitoring value of the abnormal internal resistance battery cell. When this monitoring value reaches the alarm threshold set by the BMS, the system will trigger an over-temperature alarm. During the charging and discharging process, the battery cell with abnormal internal resistance will transfer heat to the adjacent battery cell due to its high heat generation. This heat transfer will cause the temperature of the adjacent NTC monitoring point to rise. Once this temperature exceeds the alarm threshold set by the BMS, the vehicle system will immediately issue a battery cell over-temperature alarm. This means that the NTC monitoring point needs to be able to accurately capture the abnormal increase in battery cell temperature and trigger the alarm mechanism when necessary to ensure that the battery system can respond quickly when an abnormal situation occurs, thereby avoiding potential safety hazards.

[0082] There are two situations in which the rationality evaluation results of the temperature monitoring scheme are generated:

[0083] First, if the thermal simulation temperature monitoring result can simultaneously meet the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion requirements, then the rationality evaluation result of the temperature monitoring scheme is determined to be a reasonable setting;

[0084] Second, if the thermal simulation temperature monitoring result cannot simultaneously meet the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion requirements, the rationality evaluation result of the temperature monitoring scheme is determined to be unreasonable, and the temperature monitoring scheme is optimized.

[0085] Specifically, after thermal simulation temperature monitoring, it was found that the results obtained can meet the requirements of the preset battery cell safety performance criteria and the BMS over-temperature alarm threshold criteria. In other words, the built-in maximum temperature of the battery cell with abnormal internal resistance during the simulation process is always lower than the closed-cell temperature of the insulation material, ensuring the thermal safety performance of the battery cell. At the same time, the temperature of the adjacent NTC monitoring point also reaches the alarm threshold set by the BMS. When the temperature rises abnormally, the BMS can issue an alarm in time to alert the operator. It can be determined that the rationality assessment result of the temperature monitoring scheme is "reasonable setting".

[0086] In another case, the thermal simulation temperature monitoring results failed to meet the requirements of both the preset battery cell safety performance criteria and the BMS over-temperature alarm threshold criteria. Specifically, the built-in maximum temperature of the battery cell with abnormal internal resistance exceeds the closed-cell temperature of the insulation material, or the temperature of the adjacent NTC monitoring point does not reach the alarm threshold set by the BMS. In this case, the thermal safety performance of the battery cell cannot be guaranteed, and the alarm mechanism of the BMS cannot be triggered in time, thereby increasing the safety risks of the battery system. Therefore, we determined that the rationality assessment result of the temperature monitoring scheme was "unreasonable setting", and the temperature monitoring scheme needs to be optimized to improve its accuracy and reliability.

[0087] By evaluating the thermal simulation temperature monitoring results, the rationality of the temperature monitoring plan can be judged, and corresponding optimization adjustments can be made according to the evaluation results by adjusting the thickness of the insulation cotton, increasing the number of NTCs, re-determining the location of the temperature anomaly points, etc., and the simulation can be re-performed to judge the rationality, so as to finally obtain a reasonable temperature monitoring plan.

[0088] It can be seen from the above technical solutions that the embodiments of the present application provide a battery temperature monitoring solution evaluation method, device, equipment and readable storage medium. When evaluating the battery temperature monitoring solution, the present application not only considers the performance of the battery cell under normal operating conditions, but also introduces the battery cell internal resistance increase coefficient to simulate the change in internal resistance of the battery cell under abnormal conditions. This enables the present application to more accurately evaluate the temperature monitoring needs of the battery cell when facing increased internal resistance or internal safety risks. The simulated battery cell internal resistance and current change data are calculated based on the battery cell's own performance parameters, and a QR curve is constructed to characterize the relationship between the battery cell's heat generation and internal resistance change under different operating conditions, and the maximum battery cell internal resistance is determined, which can better reflect the changes in the battery cell in actual use, thereby improving the accuracy and rationality of the evaluation.

[0089] Secondly, during the evaluation process, this application fully considered the impact of different insulation schemes on the temperature monitoring of the battery system. By designing the NTC arrangement scheme and insulation scheme applied to the battery box, and setting the abnormal internal resistance battery cells and temperature monitoring scheme, this application can evaluate the impact of different insulation material thicknesses, materials, and spacing arrangements on heat conduction between battery cells. At the same time, thermal simulation is performed in combination with the digital model of the battery box and the operating conditions of the whole vehicle to simulate the temperature changes of the battery cells under different insulation schemes, so as to more accurately evaluate the rationality of the temperature monitoring scheme.

[0090] In addition, by setting the location and number of abnormal internal resistance cells, the present invention can timely discover and optimize the safety weaknesses of the battery system during the development and design stage. At the same time, combined with the preset cell safety performance criteria and the BMS over-temperature alarm threshold criteria, it can analyze the thermal simulation temperature monitoring results and generate a rationality evaluation result for the temperature monitoring scheme, providing strong support for the design and optimization of the battery system.

[0091] In some embodiments of the present application, step S1, generating simulated cell internal resistance and current change data according to the basic cell performance parameters, the cell power MAP table, the evaluated ambient temperature and the preset internal resistance growth coefficient, is introduced, which may specifically include:

[0092] Step S11, generating battery cell internal resistance calculation benchmark data according to battery cell performance basic parameters, evaluation ambient temperature, and a system power MAP table converted based on a battery cell power MAP table.

[0093] Specifically, first, based on the basic performance parameters of the battery cell, determine the performance parameters such as the internal resistance and open circuit voltage of the battery cell at the same temperature and state of charge, as well as the initial value of the battery cell internal resistance. Next, using the correlation between the battery cell level power and the system level power, the battery cell power MAP table is converted into a system power MAP table. In this conversion process, the mean of the energy conversion coefficient and the battery cell state of charge, as well as the influence of the ambient temperature or the battery cell temperature are taken into account, thereby defining the temperature power threshold parameters. Finally, the initial value of the battery cell internal resistance and the temperature power threshold parameters are integrated to form a benchmark data set for the calculation of the battery cell internal resistance. Therefore, the process of obtaining the system power MAP table and generating the benchmark data for the calculation of the battery cell internal resistance may include:

[0094] ① Based on the basic performance parameters of the battery cell, determine the internal resistance performance parameters, open circuit voltage performance parameters and initial value of the battery cell internal resistance at the same temperature and charge state;

[0095] ② According to the correlation between the cell-level power and the system-level power, the cell power MAP table is converted into the system power MAP table, and the temperature power threshold parameter is defined in combination with the internal resistance performance parameter, the open circuit voltage performance parameter and the evaluation ambient temperature;

[0096] The correlation between the cell level power and the system level power is:

[0097]

[0098] in, The power of a single battery cell at the system level; is the average power value at the cell level; is the temperature; ζ is the energy conversion coefficient, which is between 0.8 and 0.95; T is the ambient temperature or the cell temperature; SOC is the kneading function, which takes the average value of the cell state of charge.

[0099] ③ Integrate the initial value of the battery cell internal resistance and the temperature power threshold parameter to generate battery cell internal resistance calculation benchmark data.

[0100] Step S12: determining the simulated cell internal resistance according to the cell internal resistance initial value in the cell internal resistance calculation benchmark data and in combination with a preset internal resistance growth coefficient.

[0101] Specifically, considering that the change range of the internal resistance DCR of the battery cell during practical use or under internal abnormal conditions is difficult to predict, the internal resistance R0 of the battery cell in the initial state is used as the internal resistance reference value, and the R value growth coefficient is introduced to generate a simulated battery cell internal resistance to simulate the gradual increase of the internal resistance of the battery cell during use or under internal abnormal conditions, which can be expressed as the following relationship:

[0102]

[0103] Specifically, the initial internal resistance value R0 of the battery cell can be obtained by looking up a table related to temperature t and state of charge SOC. In order to simulate the gradual increase of the internal resistance of the battery cell, the internal resistance growth coefficient λ is introduced. This coefficient reflects the growth of the internal resistance of the battery cell over time, usage conditions and other factors. The smaller the value of λ, the higher the accuracy of the simulation of the increase of the internal resistance of the battery cell, and the value is usually between 0.001 and 0.1.

[0104] Step S13, calculating the temperature power threshold parameter in the reference data according to the cell internal resistance, combining the simulated cell internal resistance, determining the current-power variation relationship, and generating current variation data.

[0105] Specifically, firstly, based on the evaluation of the ambient temperature T and the various parameters obtained in the previous steps, the basic principles of electrochemistry are used for deduction, where the power P is expressed as the product of the current I and the equivalent circuit voltage CCV, that is, P=I*CCV. The equivalent circuit voltage CCV is the difference between the open circuit voltage OCV and the voltage drop caused by the current I through the internal resistance R, that is, CCV=OCV-I*R. Combining the above formulas, we can get a quadratic equation for the current I: I²*RI*OCV+P=0, which reveals the relationship between current, internal resistance, open circuit voltage and power.

[0106] At the same time, the relationship between charging and discharging power and internal resistance R is introduced: Ln(P)=-Ln(R)+Ln(a), where a is a constant introduced to simplify the formula, which is equal to (OCV-Umin)*Umin, and Umin represents the minimum voltage threshold allowed for battery cell discharge.

[0107] Combining the above formulas, the relationship between current and power change can be finally generated, and the relationship between current and power change is:

[0108]

[0109] Among them, OCV is the open circuit voltage performance parameter; R is the simulated battery cell internal resistance; P is the temperature power threshold parameter.

[0110] By using the relationship between current and power change, the temperature power threshold parameter in the reference data can be calculated according to the internal resistance of the battery cell, and the current change data can be generated in combination with the simulated internal resistance of the battery cell.

[0111] The present application is further described below with an example. Figure 5 and Figure 6 The two design alternatives shown are evaluated and compared.

[0112] Working conditions description:

[0113] 1. The initial temperature of the environment and the battery cell is set to 35°C.

[0114] 2. The initial state of charge (SOC) of the battery cell is 100%.

[0115] 3. The thermal management strategy is: start when the maximum temperature of the battery cell Tmax reaches or exceeds 32°C, and shut down when Tmax drops to 28°C or below. The inlet water temperature of the thermal management system is kept constant at 25°C, and the flow rate is 10L / min.

[0116] 4. The working condition requires discharging at a maximum current of 450A until the SOC drops to 0%. During this process, there is an abnormal cell with an internal resistance of 1.51mΩ.

[0117] Result judgment:

[0118] During the discharge process, when the readings of the NTC temperature sensor tend to balance (i.e., the temperature change is no longer significant), it is observed that the maximum temperature recorded by the NTC A sensor at the two-cell position is 56°C, which is lower than the cell overtemperature threshold of 57°C set by the battery management system (BMS). However, the maximum temperature recorded by the NTC B sensor at the one-cell position is 59.26°C, which is higher than the BMS cell overtemperature threshold of 57°C.

[0119] The highest temperature of the abnormal cell reached 96.3°C, but this temperature is still lower than the closed-pore temperature line of the cell separator, which is 143°C. Therefore, from the perspective of cell thermal safety, the temperature of the abnormal cell is still within the safe range.

[0120] Evaluation conclusion:

[0121] According to the above working condition description and result judgment, when this technical solution is used for evaluation, under the current working conditions and insulation solution, the layout of solution B can meet the battery safety performance criteria and BMS over-temperature alarm threshold criteria. However, the layout of solution A cannot meet the battery safety performance criteria and BMS over-temperature alarm threshold criteria at the same time, so the layout of solution A has safety risks.

[0122] In summary, in order to ensure the safe operation of the battery system, it is recommended to optimize the layout of scheme A, or consider adopting other more effective thermal management strategies.

[0123] A battery temperature monitoring scheme evaluation device provided in an embodiment of the present application is described below. The battery temperature monitoring scheme evaluation device described below and the battery temperature monitoring scheme evaluation method described above can refer to each other.

[0124] See also Figure 7 , Figure 7 A schematic diagram of a battery temperature monitoring scheme evaluation device disclosed in an embodiment of the present application.

[0125] like Figure 7 As shown, the battery temperature monitoring scheme evaluation device may include:

[0126] The basic parameter unit 110 is used to generate simulated cell internal resistance and current change data according to the basic parameters of cell performance, the cell power MAP table, the evaluation environment temperature and the preset internal resistance growth coefficient;

[0127] A relationship curve unit 120 is used to simulate and construct a QR curve representing the relationship between the heating value and the internal resistance change of the battery cell under different working conditions based on the current change data and the simulated battery cell internal resistance, and determine the maximum battery cell internal resistance;

[0128] The scheme design unit 130 is used to design an NTC arrangement scheme and a heat insulation scheme for the battery box, and set an abnormal internal resistance battery cell and a temperature monitoring scheme, wherein the NTCs are evenly spaced along the battery cell arrangement position, and the abnormal internal resistance battery cell is any battery cell between two NTCs;

[0129] The simulation monitoring unit 140 is used to perform thermal simulation on the battery box according to the digital model of the battery box and the operating condition of the whole vehicle by setting the abnormal internal resistance battery cell to the maximum battery cell internal resistance to obtain a thermal simulation temperature monitoring result;

[0130] The analysis and evaluation unit 150 is used to analyze the thermal simulation temperature monitoring result according to the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion, and generate a rationality evaluation result of the temperature monitoring scheme.

[0131] It can be seen from the above technical solutions that the embodiments of the present application provide a battery temperature monitoring solution evaluation method, device, equipment and readable storage medium. When evaluating the battery temperature monitoring solution, the present application not only considers the performance of the battery cell under normal operating conditions, but also introduces the battery cell internal resistance increase coefficient to simulate the change in internal resistance of the battery cell under abnormal conditions. This enables the present application to more accurately evaluate the temperature monitoring needs of the battery cell when facing increased internal resistance or internal safety risks. The simulated battery cell internal resistance and current change data are calculated based on the battery cell's own performance parameters, and a QR curve is constructed to characterize the relationship between the battery cell's heat generation and internal resistance change under different operating conditions, and the maximum battery cell internal resistance is determined, which can better reflect the changes in the battery cell in actual use, thereby improving the accuracy and rationality of the evaluation.

[0132] Secondly, during the evaluation process, this application fully considered the impact of different insulation schemes on the temperature monitoring of the battery system. By designing the NTC arrangement scheme and insulation scheme applied to the battery box, and setting the abnormal internal resistance battery cells and temperature monitoring scheme, this application can evaluate the impact of different insulation material thicknesses, materials, and spacing arrangements on heat conduction between battery cells. At the same time, thermal simulation is performed in combination with the digital model of the battery box and the operating conditions of the whole vehicle to simulate the temperature changes of the battery cells under different insulation schemes, so as to more accurately evaluate the rationality of the temperature monitoring scheme.

[0133] In addition, by setting the location and number of abnormal internal resistance cells, the present invention can timely discover and optimize the safety weaknesses of the battery system during the development and design stage. At the same time, combined with the preset cell safety performance criteria and the BMS over-temperature alarm threshold criteria, it can analyze the thermal simulation temperature monitoring results and generate a rationality evaluation result for the temperature monitoring scheme, providing strong support for the design and optimization of the battery system.

[0134] Optionally, the basic parameter unit may include:

[0135] A benchmark data unit is used to generate benchmark data for calculating the internal resistance of a battery cell based on basic parameters of battery cell performance, an evaluation environment temperature, and a system power MAP table converted from a battery cell power MAP table;

[0136] A simulated internal resistance unit, used to determine the simulated battery cell internal resistance according to the battery cell internal resistance calculation initial value in the reference data and in combination with a preset internal resistance growth coefficient;

[0137] The current data unit is used to calculate the temperature power threshold parameter in the reference data according to the internal resistance of the battery cell, determine the relationship between current and power change in combination with the simulated internal resistance of the battery cell, and generate current change data.

[0138] Optionally, the reference data unit may include:

[0139] The parameter analysis unit is used to determine the internal resistance performance parameters, open circuit voltage performance parameters and initial value of the internal resistance of the battery cell at the same temperature and charge state based on the basic performance parameters of the battery cell;

[0140] A power threshold unit, used to convert the cell power MAP table into a system power MAP table according to the correlation between the cell level power and the system level power, and to define a temperature power threshold parameter in combination with the internal resistance performance parameter, the open circuit voltage performance parameter and the evaluated ambient temperature;

[0141] The data integration unit is used to integrate the initial value of the battery cell internal resistance and the temperature power threshold parameter to generate battery cell internal resistance calculation benchmark data.

[0142] Optionally, the current and power change relationship is:

[0143]

[0144] Among them, OCV is the open circuit voltage performance parameter; R is the simulated battery cell internal resistance; P is the temperature power threshold parameter.

[0145] Optionally, the correlation between the cell level power and the system level power is:

[0146]

[0147] in, It is the power of a single battery cell at the system level; is the average power value at the cell level; is the temperature; ζ is the energy conversion coefficient, which is between 0.8 and 0.95; T is the ambient temperature or the cell temperature; SOC is the kneading function, which takes the average value of the cell state of charge.

[0148] Optionally, the analysis and evaluation unit may include:

[0149] A first evaluation unit is used to evaluate the rationality of the temperature monitoring scheme as being reasonably set when the thermal simulation temperature monitoring result can simultaneously meet the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion requirements;

[0150] The second evaluation unit is used to evaluate the rationality of the temperature monitoring scheme as unreasonable setting when the thermal simulation temperature monitoring result cannot simultaneously meet the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion requirements, and optimize the temperature monitoring scheme.

[0151] Optionally, the safety performance criterion of the battery cell is that the maximum built-in temperature of the battery cell with abnormal internal resistance obtained by simulation under vehicle working conditions is lower than the closed-cell temperature of the thermal insulation material;

[0152] The BMS over-temperature alarm threshold judgment criterion is that the adjacent NTC monitoring value of the abnormal internal resistance battery cell reaches the BMS alarm setting threshold.

[0153] The battery temperature monitoring scheme evaluation device provided in the embodiment of the present application can be applied to a battery temperature monitoring scheme evaluation device. Figure 8 The hardware structure diagram of the battery temperature monitoring solution evaluation device is shown in FIG. Figure 8 , the hardware structure of the battery temperature monitoring scheme evaluation device may include: at least one processor 1, at least one communication interface 2, at least one memory 3 and at least one communication bus 4;

[0154] In the embodiment of the present application, the number of the processor 1, the communication interface 2, the memory 3, and the communication bus 4 is at least one, and the processor 1, the communication interface 2, and the memory 3 communicate with each other through the communication bus 4;

[0155] The processor 1 may be a central processing unit CPU, or an application-specific integrated circuit ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention, etc.;

[0156] The memory 3 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), etc., such as at least one disk memory;

[0157] The memory stores a program, and the processor can call the program stored in the memory, wherein the program is used to:

[0158] Generate simulated cell internal resistance and current change data based on the basic cell performance parameters, cell power MAP table, assessed ambient temperature, and preset internal resistance growth coefficient;

[0159] Based on the current change data and the simulated battery cell internal resistance, a QR curve is simulated to characterize the relationship between the battery cell heating value and the internal resistance change under different working conditions, and the maximum battery cell internal resistance is determined;

[0160] Design an NTC arrangement scheme and a heat insulation scheme for the battery box, and set an abnormal internal resistance battery cell and a temperature monitoring scheme, wherein the NTCs are evenly spaced along the battery cell arrangement position, and the abnormal internal resistance battery cell is any battery cell between two NTCs;

[0161] According to the digital model of the battery box and the operating conditions of the whole vehicle, a thermal simulation is performed on the battery box by setting the abnormal internal resistance battery cell to the maximum battery cell internal resistance to obtain a thermal simulation temperature monitoring result;

[0162] The thermal simulation temperature monitoring result is analyzed according to the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion to generate a rationality evaluation result of the temperature monitoring scheme.

[0163] Optionally, the detailed functions and extended functions of the program may refer to the above description.

[0164] The embodiment of the present application further provides a readable storage medium, which may store a program suitable for execution by a processor, wherein the program is used to:

[0165] Generate simulated cell internal resistance and current change data based on the basic cell performance parameters, cell power MAP table, assessed ambient temperature, and preset internal resistance growth coefficient;

[0166] Based on the current change data and the simulated battery cell internal resistance, a QR curve is simulated to characterize the relationship between the battery cell heating value and the internal resistance change under different working conditions, and the maximum battery cell internal resistance is determined;

[0167] Design an NTC arrangement scheme and a heat insulation scheme for the battery box, and set an abnormal internal resistance battery cell and a temperature monitoring scheme, wherein the NTCs are evenly spaced along the battery cell arrangement position, and the abnormal internal resistance battery cell is any battery cell between two NTCs;

[0168] According to the digital model of the battery box and the operating conditions of the whole vehicle, a thermal simulation is performed on the battery box by setting the abnormal internal resistance battery cell to the maximum battery cell internal resistance to obtain a thermal simulation temperature monitoring result;

[0169] The thermal simulation temperature monitoring result is analyzed according to the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion to generate a rationality evaluation result of the temperature monitoring scheme.

[0170] Optionally, the detailed functions and extended functions of the program may refer to the above description.

[0171] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0172] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0173] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery temperature monitoring scheme evaluation method, characterized in that: include: Generate simulated cell internal resistance and current change data according to the basic cell performance parameters, the cell power MAP table, the evaluation environment temperature and the preset internal resistance growth coefficient, wherein the basic cell performance parameters include the cell internal resistance and open circuit voltage values ​​at different temperatures and charge states; Based on the current change data and the simulated battery cell internal resistance, a QR curve is simulated to characterize the relationship between the battery cell heating value and the internal resistance change under different working conditions, and the maximum battery cell internal resistance is determined; Design an NTC arrangement scheme and a heat insulation scheme for the battery box, and set an abnormal internal resistance battery cell and a temperature monitoring scheme, wherein the NTCs are evenly spaced along the battery cell arrangement position, and the abnormal internal resistance battery cell is any battery cell between two NTCs; According to the digital model of the battery box and the operating conditions of the whole vehicle, a thermal simulation is performed on the battery box by setting the abnormal internal resistance battery cell to the maximum battery cell internal resistance to obtain a thermal simulation temperature monitoring result; Analyze the thermal simulation temperature monitoring result according to the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion, and generate a rationality evaluation result of the temperature monitoring scheme; The method generates simulated cell internal resistance and current change data according to the basic cell performance parameters, the cell power MAP table, the evaluated ambient temperature and the preset internal resistance growth coefficient, including: Generate the cell internal resistance calculation benchmark data based on the basic cell performance parameters, the evaluation ambient temperature, and the system power MAP table converted from the cell power MAP table; Determine the simulated cell internal resistance according to the cell internal resistance initial value in the cell internal resistance calculation benchmark data and a preset internal resistance growth coefficient; According to the temperature power threshold parameter in the battery cell internal resistance calculation benchmark data, combined with the simulated battery cell internal resistance, a current accompanying power change relationship is determined, and current change data is generated.

2. The method according to claim 1, characterized in that The method of generating the cell internal resistance calculation benchmark data based on the basic cell performance parameters, the evaluation ambient temperature and the system power MAP table converted based on the cell power MAP table includes: Based on the basic performance parameters of the battery cells, determine the internal resistance performance parameters, open circuit voltage performance parameters and initial value of the internal resistance of the battery cells at the same temperature and charge state; The cell power MAP table is converted into a system power MAP table according to the correlation between the cell level power and the system level power, and the temperature power threshold parameter is defined in combination with the internal resistance performance parameter, the open circuit voltage performance parameter and the evaluation ambient temperature; The battery cell internal resistance initial value and the temperature power threshold parameter are integrated to generate battery cell internal resistance calculation benchmark data.

3. The method according to claim 2, characterized in that The relationship between the current and power change is: ； Among them, OCV is the open circuit voltage performance parameter; R is the simulated battery cell internal resistance; P is the temperature power threshold parameter.

4. The method according to claim 2, characterized in that: The correlation between the cell level power and the system level power is: ； in, It is the power of a single battery cell at the system level; is the average power value at the cell level; is the temperature; ζ is the energy conversion coefficient, which is between 0.8 and 0.95; T is the ambient temperature; SOC is the kneading function, which takes the average value of the battery cell state of charge.

5. The method according to claim 1, characterized in that The analyzing the thermal simulation temperature monitoring result according to the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion to generate a rationality evaluation result of the temperature monitoring scheme includes: If the thermal simulation temperature monitoring result can simultaneously meet the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion requirement, then the rationality evaluation result of the temperature monitoring scheme is determined to be a reasonable setting; If the thermal simulation temperature monitoring result cannot simultaneously meet the preset battery cell safety performance criterion and the BMS over-temperature alarm threshold criterion requirements, the rationality evaluation result of the temperature monitoring scheme is determined to be unreasonable, and the temperature monitoring scheme is optimized.

6. The method according to claim 1, characterized in that The safety performance criterion of the battery cell is that the maximum built-in temperature of the battery cell with abnormal internal resistance obtained by simulation under vehicle working conditions is lower than the closed-cell temperature of the thermal insulation material; The BMS over-temperature alarm threshold judgment criterion is that the adjacent NTC monitoring value of the abnormal internal resistance battery cell reaches the BMS alarm setting threshold.

7. A battery temperature monitoring scheme evaluation device, characterized in that: include: A basic parameter unit is used to generate simulated cell internal resistance and current change data according to the basic cell performance parameters, the cell power MAP table, the assessed ambient temperature, and the preset internal resistance growth coefficient. The basic cell performance parameters include the cell internal resistance and open circuit voltage values ​​at different temperatures and charge states. A relationship curve unit, for simulating and constructing a QR curve representing the relationship between the heating value and the internal resistance change of the battery cell under different working conditions based on the current change data and the simulated battery cell internal resistance, and determining the maximum battery cell internal resistance; A scheme design unit is used to design an NTC arrangement scheme and a heat insulation scheme for the battery box, and set an abnormal internal resistance battery cell and a temperature monitoring scheme, wherein the NTCs are evenly spaced along the battery cell arrangement position, and the abnormal internal resistance battery cell is any battery cell between two NTCs; A simulation monitoring unit is used to perform thermal simulation on the battery box according to the digital model of the battery box and the operating condition of the whole vehicle by setting the abnormal internal resistance battery cell to the maximum battery cell internal resistance to obtain a thermal simulation temperature monitoring result; An analysis and evaluation unit, configured to analyze the thermal simulation temperature monitoring result according to a preset battery cell safety performance criterion and a BMS over-temperature alarm threshold criterion, and generate a rationality evaluation result of the temperature monitoring scheme; The method generates simulated cell internal resistance and current change data according to the basic cell performance parameters, the cell power MAP table, the evaluated ambient temperature and the preset internal resistance growth coefficient, including: Generate the cell internal resistance calculation benchmark data based on the basic cell performance parameters, the evaluation ambient temperature, and the system power MAP table converted from the cell power MAP table; Determine the simulated cell internal resistance according to the cell internal resistance initial value in the cell internal resistance calculation benchmark data and a preset internal resistance growth coefficient; According to the temperature power threshold parameter in the battery cell internal resistance calculation benchmark data, combined with the simulated battery cell internal resistance, a current accompanying power change relationship is determined, and current change data is generated.

8. A battery temperature monitoring scheme evaluation device, characterized in that: including memory and processor; The memory is used to store programs; The processor is used to execute the program to implement each step of the battery temperature monitoring solution evaluation method according to any one of claims 1 to 6.

9. A readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, each step of the battery temperature monitoring scheme evaluation method according to any one of claims 1 to 6 is implemented.

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