Battery pack condensation prevention and control method, device, system and storage medium

Abstract

The application provides a condensation prevention and control method, device and system of a battery pack and a storage medium. The method comprises the following steps: constructing a multi-physical field coupling model of the battery pack based on temperature field related parameters and humidity field related parameters of the battery pack; inputting initial working condition data of the battery pack into the multi-physical field coupling model to obtain an initial temperature of a material surface corresponding to a target region of the battery pack; determining a risk level of the material surface corresponding to the target region forming condensation based on a dew point temperature of the target region and the initial temperature, and performing condensation prevention and control on the target region according to the risk level. Through implementation of the application scheme, the possibility of condensation in each region of the battery pack is accurately evaluated and quantified, and then condensation prevention and control measures can be actively taken before condensation is formed, and the safety hazards of the battery pack caused by condensation in dead angle regions that cannot be visually observed can be avoided as much as possible.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a method, apparatus, system and storage medium for preventing condensation in a battery pack. Background Technology

[0002] With the rapid development of new energy technologies, the reliability of battery packs has received widespread attention. Condensation can occur within battery packs due to factors such as temperature and humidity changes, leading to an increase in liquid water and potentially causing short circuits, corrosion, and performance degradation. Numerous quality issues caused by condensation have already emerged in the market. Related technologies typically employ passive protection methods for condensation control. This involves checking for condensation after external environmental changes and battery pack charge / discharge tests, and then visually inspecting the battery pack to determine if condensation has occurred. Only after condensation has appeared can appropriate measures be taken. However, the relatively complex structure of battery packs means that functional checks and visual inspection may not be sufficient to detect condensation within the internal structure in a timely manner, making it difficult to resolve condensation-related failures promptly. Summary of the Invention

[0003] This application provides a method, apparatus, system, and storage medium for preventing condensation in battery packs, aiming to solve the problem of untimely condensation prevention in related technologies.

[0004] To achieve the above objectives, the first aspect of this application provides a method for preventing condensation in a battery pack. The method includes: constructing a multiphysics coupling model of the battery pack based on temperature field-related parameters and humidity field-related parameters; inputting initial operating condition data of the battery pack into the multiphysics coupling model to obtain the initial temperature of the material surface corresponding to a target area of ​​the battery pack; determining the risk level of condensation formation on the material surface corresponding to the target area based on the dew point temperature of the target area and the initial temperature; and implementing condensation prevention and control measures in the target area according to the risk level.

[0005] The solution provided in this application constructs a multiphysics coupling model based on temperature and humidity field parameters. This allows for a quantitative assessment of the probability of condensation occurring in target areas within the battery pack, determining the risk level of condensation formation on the corresponding material surfaces. Consequently, proactive condensation prevention measures can be implemented before condensation forms, minimizing the risk of battery pack failure due to condensation. Furthermore, by implementing this solution, the multiphysics coupling model can accurately assess and quantify the likelihood of condensation in various areas within the battery pack based on the battery pack's operating data, minimizing the risk of condensation formation in blind spots that cannot be visually observed, thus preventing potential safety hazards to the battery pack.

[0006] In some optional embodiments, constructing a multiphysics coupling model of the battery pack based on the temperature field-related parameters and humidity field-related parameters of the battery pack includes: determining a temperature field model based on the temperature field-related parameters; determining a humidity field model based on the humidity field-related parameters; and coupling the temperature field model and the humidity field model to determine the multiphysics coupling model of the battery pack.

[0007] In the solution provided in this application, the linkage between temperature, humidity and dew point can be established by coupling the temperature field model and the humidity field model, thereby enabling accurate calculation of the surface temperature of each region inside the battery pack.

[0008] In some optional embodiments, the temperature field-related parameters include at least the theoretical operating condition data of the battery pack, the fluid velocity field, and the thermal properties of the materials corresponding to each region within the battery pack. The thermal properties include at least the thermal conductivity, density, and specific heat capacity of the materials. Determining the temperature field model based on the temperature field-related parameters includes: determining the total heat source term of the first governing equation based on the theoretical operating condition data, wherein the theoretical operating condition data includes a first theoretical heat corresponding to the self-generated heat of the battery pack and a second theoretical heat corresponding to an external heat source, and the total heat source term is the sum of the first theoretical heat and the second theoretical heat; determining the heat conduction term of the first governing equation based on the thermal conductivity; determining the heat convection term of the first governing equation based on the fluid velocity field, the density, and the specific heat capacity; and determining the temperature field model based on the total heat source term, the heat conduction term, and the heat convection term.

[0009] In the solution provided in this application, influencing factors such as operating condition data, fluid velocity field, and material thermophysical parameters are introduced during the construction of the temperature field model to more accurately quantify the influence of heat source changes, heat conduction, heat convection and other processes on temperature field changes, thereby enabling more accurate prediction of the temperature distribution and variation law of the battery pack temperature field.

[0010] In some alternative embodiments, the method further includes: obtaining the theoretical operating current and theoretical cell resistance of the battery pack; and determining the first theoretical heat based on the theoretical operating current and theoretical cell resistance of the battery pack.

[0011] In the solution provided in this application, the self-generated heat of the battery pack under theoretical operating conditions can be determined based on the theoretical operating current and cell resistance, and applied to the construction process of the temperature field model to better achieve condensation control and thermal management of the battery pack.

[0012] In some alternative embodiments, the temperature field-related parameters further include a first convective heat transfer coefficient;

[0013] The method further includes: determining the first boundary conditions of the temperature field model based on the thermophysical parameters and the first convective heat transfer coefficient; and determining the first target output result of the first governing equation based on the first boundary conditions.

[0014] In the solution provided in this application, the heat exchange mode between the temperature field model and the external environment is defined by setting boundary conditions, and the physical constraints in the actual working conditions are fully considered, so that the temperature field model can accurately reflect the actual physical process, thereby improving the computational efficiency and stability of the temperature field model.

[0015] In some optional embodiments, the humidity field-related parameters include the humidity diffusion coefficient of the battery pack, the fluid velocity field accumulation term, and the humidity source term. The accumulation term indicates the rate of change of humidity over time, and the humidity source term indicates the humidity generation rate or humidity consumption rate of the battery pack per unit volume per unit time. Determining the humidity field model based on the humidity field-related parameters includes: determining the diffusion term of the second governing equation based on the humidity diffusion coefficient; determining the convective transport term of the second governing equation based on the fluid velocity field; and determining the humidity field model based on the diffusion term, the convective transport term, the accumulation term, and the humidity source term.

[0016] In the solution provided in this application, the temperature field model of the battery pack is determined based on the diffusion term, the convection transport term, the accumulation term, and the humidity source term. This can better simulate the distribution and transport of moisture inside or around the battery pack, thereby enabling more accurate condensation prediction.

[0017] In some alternative embodiments, the humidity field related parameters further include a second convective heat transfer coefficient, and the method further includes: determining a second boundary condition for the humidity field model based on the second convective heat transfer coefficient; and determining a second objective output result of the second governing equation based on the second boundary condition.

[0018] In the solution provided in this application, the second boundary conditions of the humidity field model are determined based on the second convective heat transfer coefficient. By defining the variation law of the humidity field on the model boundary, the humidity field model can accurately reflect the actual physical process of the humidity field, while reducing the computational complexity.

[0019] In some optional embodiments, the step of model coupling the temperature field model and the humidity field model to determine the multiphysics coupling model of the battery pack includes: identifying the correlation factors between the temperature field model and the humidity field model; embedding the quantization relationship of the correlation factors into the temperature field model and the humidity field model respectively, and determining the bidirectional data interaction logic between the temperature field model and the humidity field model; and based on the bidirectional data interaction logic, performing bidirectional correction on the parameters of the temperature field model and the humidity field model to obtain a converged multiphysics coupling model of the battery pack.

[0020] In the solution provided in this application, two independent single-field models (i.e., temperature field model and humidity field model) are connected into a whole coupled model that can transmit information to each other based on the correlation factor effect, so as to obtain solid surface temperature and risk level assessment results that are closer to the real situation.

[0021] In some optional embodiments, the method further includes: performing finite element mesh generation on the three-dimensional geometric model of the battery pack based on the multiphysics coupling model to obtain a finite element mesh model, wherein the finite element mesh model includes mesh elements corresponding to each region of the battery pack; loading the multiphysics coupling model onto the finite element mesh model for simulation processing to obtain simulation results; and determining the solution coupling model corresponding to each mesh element of the three-dimensional geometric model based on the simulation results, wherein each solution coupling model is used to determine the material surface temperature of the corresponding mesh element under different operating conditions.

[0022] The solution provided in this application uses mesh cutting and simulation processing to optimize the multiphysics coupling model, which can effectively reduce the computational load of the model and improve the computational accuracy.

[0023] In some optional embodiments, the method further includes: comparing the simulation results of the multiphysics coupling model with the actual measurement results of the battery pack to obtain an error comparison result, wherein the simulation results include the simulated temperature of the material surface of each mesh cell under full operating conditions, and the actual measurement results include the measured temperature of the material surface of the region corresponding to each mesh cell in the battery pack under full operating conditions; and correcting the relevant solution coupling model according to the error comparison result to obtain a corrected target solution coupling model, wherein the relevant solution coupling model includes all the solution coupling models that cause the error.

[0024] In the solution provided in this application, after the construction of the multiphysics coupling model is completed, the model parameters can be corrected based on the simulation results and actual measurement results. The determined influencing factors (including the temperature field related parameters and humidity field related parameters mentioned above) can be corrected based on the error comparison results. Furthermore, when new influencing factors are discovered, they can be introduced into the multiphysics coupling model, thereby continuously improving the calculation accuracy of solving the coupling model.

[0025] In some optional embodiments, determining the risk level of condensation formation on the material surface corresponding to the target area based on the dew point temperature of the target area and the initial temperature includes: inputting the dew point temperature of the target area and the initial temperature into a preset condensation probability assessment model to determine the probability of condensation occurrence in the target area; and determining the risk level of condensation formation on the material surface corresponding to the target area based on the probability of condensation occurrence.

[0026] In the solution provided in this application, a condensation probability assessment model is used to clarify the mapping standard between condensation probability and failure rate. This allows the condensation probability assessment model to quantitatively assess whether condensation failure may occur in the overall battery pack and in local locations based on the calculation results of the multi-physics coupling model and the relevant dew point temperature. In other words, it determines the risk level of condensation formation on the material surface corresponding to the target area of ​​the battery pack, so as to take timely preventive measures when condensation may occur.

[0027] In some alternative embodiments, the method further includes: obtaining the water vapor temperature-humidity ratio and ambient temperature in the environment where the target area is located; and determining the dew point temperature of the target area based on the water vapor temperature-humidity ratio and the ambient temperature.

[0028] The solution provided in this application determines the dew point temperature of the target area by combining the water vapor temperature-humidity ratio and ambient temperature in the target area environment. This eliminates the need for expensive dedicated dew point measurement equipment, which helps reduce the production and maintenance costs of the battery pack.

[0029] In some optional embodiments, the battery pack is connected to a gas conditioning device; the step of controlling condensation in the target area according to the risk level includes: controlling the gas conditioning device to perform nitrogen replacement with the battery pack to adjust the humidity field of the battery pack; acquiring the real-time humidity value of the battery pack and determining the real-time humidity value as the real-time operating condition data of the battery pack; inputting the real-time operating condition data into the multiphysics coupling model to output the real-time temperature of the material surface of the target area; redetermining the risk level of condensation in the target area based on the dew point temperature of the target area and the real-time temperature; if the redetermined risk level does not meet the preset condensation control conditions of the battery pack, controlling the gas conditioning device to stop the nitrogen replacement operation.

[0030] In the solution provided in this application, when the risk level of condensation formation in the battery pack is high, the humidity field of the battery pack can be adjusted by a gas conditioning device until the humidity value inside the battery pack is controlled within a reasonable range. Through the cooperation between the multiphysics coupling model and the gas conditioning device, the condensation problem in the battery pack can be improved from the source, thereby enhancing the reliability of the battery pack.

[0031] A second aspect of this application provides a condensation control device for a battery pack, comprising: a construction module for constructing a multiphysics coupling model of the battery pack based on temperature field-related parameters and humidity field-related parameters of the battery pack; a determination module for inputting initial operating condition data of the battery pack into the multiphysics coupling model to obtain the initial temperature of the material surface corresponding to a target area of ​​the battery pack; and a control module for determining the risk level of condensation formation on the material surface corresponding to the target area based on the dew point temperature of the target area and the initial temperature, and controlling condensation in the target area according to the risk level.

[0032] A third aspect of this application provides a condensation prevention system for a battery pack, comprising: a memory and a processor, wherein the processor is configured to execute a determination machine program stored in the memory; when the processor executes the determination machine program, it implements the condensation prevention method for the battery pack provided in the first aspect of this application.

[0033] In some alternative embodiments, the condensation control system for the battery pack further includes a gas conditioning device communicatively connected to the processor, the gas conditioning device also being connected to the battery pack for nitrogen purging of the battery pack.

[0034] The fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements the condensation prevention method for the battery pack provided in the first aspect of this application.

[0035] It is understood that the beneficial effects of the second to fourth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1A schematic diagram illustrating a scenario for a battery pack condensation control method provided in some embodiments of this application;

[0038] Figure 2 A flowchart illustrating a method for preventing condensation in a battery pack, provided for some embodiments of this application;

[0039] Figure 3 A detailed flowchart illustrating the condensation control method for a battery pack provided in some embodiments of this application;

[0040] Figure 4 A schematic diagram of a condensation control device provided in some embodiments of this application;

[0041] Figure 5 A schematic diagram of the structure of a condensation control system for a battery pack provided in some embodiments of this application;

[0042] Figure 6 This application provides a schematic diagram of the structure of a gas regulating device and a battery pack according to some embodiments;

[0043] Figure 7 This is a schematic diagram of the structure of a computer-readable storage medium for storing or carrying program code that implements the condensation prevention method for a battery pack provided in the embodiments of this application, as provided in some embodiments of this application. Detailed Implementation

[0044] To make the inventive objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0045] In the following description, when referring to the accompanying drawings, the same numbers in different drawings denote the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0046] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0047] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0048] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0049] Furthermore, in the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0050] In related technologies, condensation protection methods for battery packs are typically passive. Measures taken to address potential safety issues caused by condensation are usually reactive rather than proactive. Furthermore, battery pack structures are relatively complex, and condensation may occur in locations not directly observable by the naked eye, making it difficult to detect visually. For multi-layered battery packs, condensate may even flow along the structural interfaces to the lower layers, expanding the risk area. Therefore, quantitatively characterizing the probability of condensation in battery packs and implementing proactive condensation control measures has become a major challenge for designers.

[0051] To address the aforementioned issues, and considering that condensation formation depends on two key factors—temperature and humidity—and that these two fields influence each other, the condensation prevention method, apparatus, system, and storage medium for battery packs provided in this application construct a multi-physics coupling model based on the temperature and humidity field parameters of the battery pack. This model is used to locate the dynamic correlation between the temperature and humidity fields, thereby accurately assessing the risk level of condensation. Consequently, proactive preventative measures can be taken before condensation occurs, significantly improving the reliability of the battery pack.

[0052] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments.

[0053] Please see Figure 1 , Figure 1This is a schematic diagram illustrating a scenario of a condensation control method for a battery pack 101 provided in some embodiments of this application. The application scenario of this condensation control method can be a condensation control system 100 for the battery pack 101. The condensation control system 100 can be integrated into the battery management system (BMS) or it can be a system independent of the battery management system, without any limitation.

[0054] The condensation control system 100 may include a data acquisition module 1001, a decision-making module 1002, and an execution module 1003. The data acquisition module 1001, decision-making module 1002, and execution module 1003 can be connected to the battery pack 101 respectively. The data acquisition module 1001 can acquire operating data of the battery pack 101, including operating current, cell resistance, internal temperature, external temperature, internal humidity, and external humidity. Correspondingly, the data acquisition module 1001 may include a temperature sensor. The system includes a humidity sensor and a data acquisition submodule for obtaining battery status parameters. The data acquisition submodule can be a sensor or a specific sampling circuit, used to directly or indirectly acquire battery status parameters such as operating current and cell resistance of the battery pack 101. Multiple temperature sensors can be set, and these sensors can be installed both inside and outside the battery pack 101 to acquire internal and external temperature values. Similarly, multiple humidity sensors can be set, both inside and outside the battery pack 101, to acquire internal and external humidity values; no limitation is placed on this. The decision module 1002 can assess the risk level of condensation in the battery pack 101 based on the operating data acquired by the data acquisition module 1001. The execution module 1003 can proactively control condensation in the battery pack 101 based on the risk level determined by the decision module 1002.

[0055] Please see Figure 2 , Figure 2 This application provides a flowchart illustrating a method for preventing condensation in a battery pack, as shown in some embodiments. In specific embodiments, this method can be applied to, for example... Figure 1 The condensation control system shown below describes the specific process of condensation control for this battery pack as follows:

[0056] S201. Based on the temperature field-related parameters and humidity field-related parameters of the battery pack, construct a multi-physics coupling model of the battery pack.

[0057] In this embodiment, temperature field-related parameters can refer to parameters related to heat sources that may affect changes in the temperature field, and humidity field-related parameters can refer to various moisture-related parameters that may cause changes in the humidity field of the battery pack. In the condensation control method of this embodiment, the influence of temperature and humidity on the probability of condensation formation is fully considered. A multiphysics coupling model is constructed based on temperature field-related parameters and humidity field-related parameters, which helps improve the accuracy of material surface temperature calculation and the precision of risk level prediction.

[0058] In some optional embodiments, a multi-physics coupling model of the battery pack is constructed based on the temperature field-related parameters and humidity field-related parameters of the battery pack, including: determining a temperature field model based on the temperature field-related parameters; determining a humidity field model based on the humidity field-related parameters; and coupling the temperature field model and the humidity field model to determine the multi-physics coupling model of the battery pack.

[0059] In the solution provided in this application, the temperature field model can refer to a mathematical model of the temperature field change over time at various spatial locations within the battery pack, and the humidity field model can refer to a mathematical model of the humidity field change over time at various spatial locations within the battery pack, where the relative or absolute humidity changes over time. In this embodiment, the linkage between temperature, humidity, and dew point can be established through the coupling between the temperature field model and the humidity field model, thereby enabling accurate calculation of the surface temperature of each region inside the battery pack.

[0060] In some optional embodiments, the temperature field-related parameters include at least the theoretical operating condition data of the battery pack, the fluid velocity field, and the thermal properties of the materials corresponding to each region within the battery pack. These thermal properties include at least the thermal conductivity, density, and specific heat capacity of the materials. Based on the temperature field-related parameters, a temperature field model is determined, including: determining the total heat source term of the first governing equation based on the theoretical operating condition data, wherein the theoretical operating condition data includes the first theoretical heat generated by the battery pack itself and the second theoretical heat generated by an external heat source, and the total heat source term is the sum of the first and second theoretical heats; determining the heat conduction term of the first governing equation based on the thermal conductivity; determining the heat convection term of the first governing equation based on the fluid velocity field, density, and specific heat capacity; and determining the temperature field model based on the total heat source term, the heat conduction term, and the heat convection term.

[0061] In the solution provided in this application, the relevant parameters of each temperature field can be obtained through theoretical calculations, database searches, or empirical tests, without any limitations. Theoretical operating condition data can be operating condition data determined during the battery pack design or testing phase. Introducing theoretical operating condition data when constructing the temperature field model allows the model to better simulate the temperature changes of the battery pack under transient and alternating loads. The fluid velocity field describes the flow of fluid media (such as air, coolant in liquid cooling plates, etc.) inside the battery pack, including flow velocity, flow direction, and distribution. During product development, the fluid velocity field can be determined using fluid dynamics software and stored in a database. When constructing the temperature field model, it can be directly retrieved from the database. Thermophysical parameters can be used to characterize the thermophysical properties of various materials constituting the battery pack (such as cells, busbars, cooling plates, thermal insulation, thermally conductive adhesive, shell, etc.). By applying the thermophysical parameters of materials of different components in the model, the changes in the temperature field under different operating conditions can be better simulated. Based on the embodiments of this application, influencing factors such as operating condition data, fluid velocity field, and material thermophysical parameters are introduced during the construction of the temperature field model to more accurately quantify the impact of heat source changes, heat conduction, and heat convection on temperature field changes, thereby enabling more precise prediction of the temperature distribution and variation patterns of the battery pack temperature field. In this embodiment, the process of determining the temperature field model mainly includes: determining the first governing equation of the temperature field model.

[0062] In some implementations, the first governing equation can be expressed as:

[0063]

[0064] in, Represents the heat conduction term. Represents the heat convection term. Represents the total heat source term. Indicates thermal conductivity. Indicates density, Indicates specific heat capacity. Represents the gradient operator, Represents temperature variable. express The rate of change and direction of change in the temperature field. This represents the fluid velocity field.

[0065] In some optional embodiments, the condensation control method further includes: obtaining the theoretical operating current and theoretical cell resistance of the battery pack; and determining the first theoretical heat based on the theoretical operating current and theoretical cell resistance of the battery pack.

[0066] In the solution provided in this application, the self-generated heat of the battery pack under theoretical operating conditions can be determined based on the theoretical operating current and cell resistance, and applied to the construction process of the temperature field model to better achieve condensation control and thermal management of the battery pack.

[0067] In some implementations, the first theoretical heat can be calculated using the following formula:

[0068]

[0069] in, Represents the first theoretical heat. Indicates the theoretical operating current. Indicates the theoretical cell resistance. This refers to the heat generated by the battery pack's self-generated heat sources other than Joule heat. These other heat sources can be one or more of the following: reaction heat, side reaction heat, polarization heat, etc., during battery pack operation.

[0070] In some optional embodiments, the temperature field related parameters also include a first convective heat transfer coefficient; the condensation control method further includes: determining the first boundary conditions of the temperature field model based on the thermophysical parameters and the first convective heat transfer coefficient; and determining the first target output result of the first governing equation based on the first boundary conditions.

[0071] In the solution provided in this application, the boundary conditions of the temperature field model are determined based on the thermal property parameters and the first convective heat transfer coefficient. By setting the boundary conditions, the heat exchange mode (convection and heat transfer) between the temperature field model and the external environment is defined, and the physical constraints in the actual working conditions are fully considered, so that the temperature field model can accurately reflect the actual physical process, thereby improving the computational efficiency and stability of the temperature field model.

[0072] In some implementations, the expression for the first boundary condition can be:

[0073]

[0074] in, Indicates thermal conductivity. Indicates temperature. Indicates the normal direction of the solid surface. This represents the temperature gradient along the normal direction of the solid surface. Indicates the first convective heat transfer coefficient. This represents the solid surface temperature output by the temperature field model. This represents the fluid temperature output by the temperature field model.

[0075] In some optional embodiments, the humidity field-related parameters include the humidity diffusion coefficient of the battery pack, the fluid velocity field accumulation term, and the humidity source term. The accumulation term indicates the rate of change of humidity over time, and the humidity source term indicates the humidity generation rate or humidity consumption rate of the battery pack per unit volume per unit time. Based on the humidity field-related parameters, the humidity field model is determined, including: determining the diffusion term of the second governing equation based on the humidity diffusion coefficient; determining the convective transport term of the second governing equation based on the fluid velocity field; and determining the humidity field model based on the diffusion term, convective transport term, accumulation term, and humidity source term.

[0076] In the solution provided in this application, the parameters related to the humidity field model can be obtained through theoretical calculations, database searches, or empirical tests, and are not limited thereto. The humidity diffusion coefficient can be used to represent the ease with which moisture diffuses in materials or air. The diffusion term represents humidity diffusion due to concentration gradients. The convection transport term represents humidity transport due to fluid flow (such as cooling air). Determining the temperature field model of the battery pack based on the diffusion term, convection transport term, accumulation term, and humidity source term can better simulate the distribution and transport of moisture inside or around the battery pack, thereby enabling more accurate condensation prediction. In this embodiment, the process of determining the humidity field model mainly includes: determining the second governing equation of the humidity field model.

[0077] In some implementations, the second governing equation can be expressed as:

[0078]

[0079] in, Indicates humidity variable, Indicates time, Represents the fluid velocity field. Represents the gradient operator, express The rate of change and direction of change in the humidity field. Indicates the humidity diffusion coefficient. Indicates cumulative terms. This represents a stream transmission term, indicating that... Represents the diffusion term. This indicates a humidity source item.

[0080] In some optional embodiments, the humidity field related parameters also include a second convective heat transfer coefficient, and the condensation control method further includes: determining a second boundary condition of the humidity field model based on the second convective heat transfer coefficient; and determining a second objective output result of the second control equation based on the second boundary condition.

[0081] In the solution provided in this application, the second boundary condition of the humidity field model is determined based on the second convective heat transfer coefficient. By defining the variation law of the humidity field on the model boundary, the humidity field model can accurately reflect the actual physical process of the humidity field, while reducing the computational complexity. It can be understood that the setting of the second boundary condition, while satisfying the completeness of the mathematical solution of the second governing equation, also achieves reasonable physical constraints and efficiency optimization of the humidity field, laying the computational foundation for subsequent multi-field coupling and risk level assessment processes. It also enables the humidity field model to realistically and efficiently guide the design and optimization of the battery pack.

[0082] In some implementations, the expression for the second boundary condition can be:

[0083]

[0084] in, Indicates the normal direction of the solid surface. This represents the humidity gradient along the normal direction of the solid surface. Indicates the second convective heat transfer coefficient. This represents the solid surface humidity output by the humidity field model. This represents the fluid humidity output by the humidity field model.

[0085] In some optional embodiments, the temperature field model and the humidity field model are coupled to determine the multi-physics coupling model of the battery pack, including: identifying the correlation factors between the temperature field model and the humidity field model; embedding the quantification relationship of the correlation factors into the temperature field model and the humidity field model respectively, and determining the bidirectional data interaction logic between the temperature field model and the humidity field model; and based on the bidirectional data interaction logic, performing bidirectional correction on the parameters of the temperature field model and the humidity field model to obtain the converged multi-physics coupling model of the battery pack.

[0086] In the solution provided in this application, the correlation factor can refer to the specific factors that influence each other in the temperature field and humidity field. For example, the correlation factor can be relative humidity, moisture diffusion coefficient, etc. In the condensation control method of this application embodiment, the correlation factor between the temperature field model and the humidity field model is identified. Then, the correlation factor can be quantified by expression and embedded into the model, so that the temperature field model and the humidity field model can be bidirectionally corrected based on each other's calculation results. In this way, based on the correlation factor effect, two independent single-field models (i.e., the temperature field model and the humidity field model) are connected into a whole coupled model that can transmit information to each other, so as to obtain a solid surface temperature and risk level assessment result that is closer to the real situation.

[0087] In some optional embodiments, the condensation control method further includes: performing finite element mesh generation on the three-dimensional geometric model of the battery pack based on a multiphysics coupling model to obtain a finite element mesh model, wherein the finite element mesh model includes mesh elements corresponding to each region of the battery pack; loading the multiphysics coupling model onto the finite element mesh model for simulation processing to obtain simulation results, and determining the solution coupling model corresponding to each mesh element of the three-dimensional geometric model based on the simulation results, wherein each solution coupling model is used to determine the material surface temperature of the corresponding mesh element under different operating conditions.

[0088] In the solution provided in this application, the finite element method is used to mesh the three-dimensional geometric model of the battery pack, decomposing the multiphysics coupling model into each mesh element. This establishes a computational framework for simulation processing, allowing simulation software to perform calculations based on this framework, obtain simulation results, and determine the corresponding solution coupling model. This embodiment, by employing mesh segmentation and simulation processing to optimize the multiphysics coupling model, effectively reduces the computational load and improves computational accuracy.

[0089] Understandably, in some specific implementations, when meshing the three-dimensional geometric model of the battery pack, the mesh can be refined in areas with a high risk of condensation. High-risk areas can refer to gaps between cells, contact points between the casing and the cells, areas near heat dissipation components, and poorly sealed seams, etc., so that the temperature and humidity calculation accuracy in these areas is high enough. For large areas of the casing and open areas with lower risk, the mesh can be appropriately simplified to balance calculation efficiency.

[0090] In some optional embodiments, the condensation control method further includes: comparing the simulation results of the multiphysics coupling model with the actual measurement results of the battery pack to obtain an error comparison result, wherein the simulation results include the simulated temperature of the material surface of each grid cell under full operating conditions, and the actual measurement results include the measured temperature of the material surface of the region corresponding to each grid cell in the battery pack under full operating conditions; and correcting the relevant solution coupling model according to the error comparison result to obtain the corrected target solution coupling model, wherein the relevant solution coupling model includes all solution coupling models that cause the error.

[0091] In the solution provided in this application, after the construction of the multiphysics coupling model is completed, the model parameters can be corrected based on the simulation results and actual measurement results. That is, the determined influencing factors (including the temperature field related parameters and humidity field related parameters mentioned above) can be corrected. The database table storing the influencing factors can be updated based on the newly determined influencing factors. New influencing factors can also be introduced into the multiphysics coupling model when they are discovered, thereby continuously improving the calculation accuracy of solving the coupling model.

[0092] It is understood that, in some specific implementations, the aforementioned actual measurement results can be actual measurement results from the market or actual measurement results from the testing end. Error analysis is performed based on the error comparison between the actual measurement results and the simulation results to identify the sources of influencing factors affecting the simulation results. Then, the model parameters can be progressively corrected based on the sources of these influencing factors. That is, iterative verification is performed based on the simulation results and actual measurement results until the error comparison between the simulation results and the actual measurement results is less than a preset threshold, ultimately obtaining a target solution coupled model that meets the accuracy requirements. In this embodiment, the battery pack can refer to the battery pack installed in an electric vehicle. When using market measurement results for model correction, information such as the ambient temperature inside and outside the battery pack, the ambient humidity inside and outside the battery pack, the operating condition data of the vehicle where the battery pack is located, and the insulation status of the battery pack can be considered as the main sources of influencing factors. When using testing end measurement results for model correction, information such as the ambient temperature inside and outside the battery pack, the ambient humidity inside and outside the battery pack, the operating condition data of the vehicle where the battery pack is located, the insulation status of the battery pack, the temperature of other heat sources in the battery pack, and fluid velocity can be considered as the main sources of influencing factors. No restrictions are imposed here.

[0093] S202. Input the initial operating condition data of the battery pack into the multiphysics coupling model to obtain the initial temperature of the material surface corresponding to the target area of ​​the battery pack.

[0094] In this embodiment, the operating condition data may include external environmental parameters of the battery pack and material-related parameters within the battery pack. External environmental parameters may include the external ambient temperature, external ambient humidity, and vehicle current operating conditions. Material-related parameters within the battery pack may include the material types of materials in different areas of the battery pack and the battery pack's digital model. The battery pack's digital model may include the battery pack's operating current, cell resistance, heat values ​​of various internal and external heat sources, and the total heat value of the battery pack's heat sources, etc., without limitation. By inputting the current initial operating condition data of the battery pack into a multiphysics coupling model, the initial temperature of the material surface corresponding to the target area of ​​the battery pack under the current operating condition can be calculated through the solution coupling model of the multiphysics coupling model. It is understood that the target area can refer to a high-risk area in the battery pack that is prone to condensation and is under close monitoring, or it can refer to the entire area within the battery pack; there is no limitation.

[0095] S203. Based on the dew point temperature and initial temperature of the target area, determine the risk level of condensation formation on the material surface corresponding to the target area, and carry out condensation control in the target area according to the risk level.

[0096] In this embodiment, condensation control measures include, but are not limited to, real-time status monitoring, issuing alarm signals, adjusting the temperature of the battery pack, and adjusting the humidity of the battery pack, etc., and are not limited thereto. In this embodiment, the risk level of condensation formation on the surface of the battery pack material can be predicted based on the calculation results of the multiphysics coupling model, and then condensation control measures can be proactively taken before condensation forms to minimize the possibility of condensation failure of the battery pack.

[0097] In some optional embodiments, the risk level of condensation formation on the material surface corresponding to the target area is determined based on the dew point temperature and initial temperature of the target area, including: inputting the dew point temperature and initial temperature of the target area into a preset condensation probability assessment model to determine the probability of condensation occurrence in the target area; and determining the risk level of condensation formation on the material surface corresponding to the target area based on the probability of condensation occurrence.

[0098] In the solution provided in this application, a condensation probability assessment model is used to clarify the mapping standard between condensation probability and failure rate. This allows the condensation probability assessment model to quantitatively assess whether condensation failure may occur in the overall battery pack and in local locations based on the calculation results of the multi-physics coupling model and the relevant dew point temperature. In other words, it determines the risk level of condensation formation on the material surface corresponding to the target area of ​​the battery pack, so as to take timely preventive measures when condensation may occur.

[0099] It should be noted that traditional condensation prevention methods typically involve passive protection after condensation risks are discovered during product testing or use. However, the multiphysics coupling model and condensation probability assessment model of this application can be applied to various stages of product development. For example, in the early stages of product development, the multiphysics coupling model and condensation probability assessment model can be used to predict the risk level of condensation generation within the battery pack, allowing for proactive design avoidance of high-risk areas. In the middle stages of product development, the multiphysics coupling model and condensation probability assessment model can guide risk assessment for market-end products. After model optimization, the product does not require actual testing; the actual market risks can be assessed in advance through modeling.

[0100] In some implementations, the expression for the condensation probability assessment model can be:

[0101]

[0102] in, Indicates the probability of condensation occurring. Indicates the initial temperature. Indicates the dew point temperature. Indicates the preset temperature difference range; when hour, ;when hour, It decreases linearly with temperature difference.

[0103] For example, in some implementations, risk levels can be categorized as low risk, medium risk, and high risk. If the condensation probability assessment model outputs the following result: If so, it can be determined that the probability of condensation on the material surface corresponding to the current target area is low, which can be recorded as low risk. The corresponding prevention and control measures can be: maintain moderate attention and do not take special measures. If the output of the condensation probability assessment model is: If the probability of condensation on the material surface in the current target area is generally considered medium risk, then the corresponding control measures could be: no action taken, issue an alarm signal, and remain vigilant. If the condensation probability assessment model outputs the following result: If so, it can be determined that the probability of condensation on the material surface corresponding to the current target area is high, which can be recorded as high risk. The corresponding prevention and control measures can be: issuing an alarm signal and adjusting the temperature and / or humidity of the battery pack.

[0104] In some optional embodiments, the condensation control method further includes: obtaining the water vapor temperature-humidity ratio and ambient temperature in the environment where the target area is located; and determining the dew point temperature of the target area based on the water vapor temperature-humidity ratio and ambient temperature.

[0105] The solution provided in this application determines the dew point temperature of the target area by combining the water vapor temperature-humidity ratio and ambient temperature in the target area environment. This eliminates the need for expensive dedicated dew point measurement equipment, which helps reduce the production and maintenance costs of the battery pack.

[0106] In some implementations, the formula for calculating the dew point temperature of the target area can be:

[0107]

[0108] in, Indicates the dew point temperature. Indicates ambient temperature. This represents the water vapor temperature-humidity ratio. The dew point temperature is calculated using the above formula. The formula is simple, has extremely low calculation delay, and can quickly respond to changes in the battery pack's internal environment, promptly triggering condensation control measures to minimize the risk of short circuits, corrosion, or performance degradation caused by condensation.

[0109] In some optional embodiments, the battery pack is connected to a gas conditioning device; condensation control of the target area is performed according to the risk level, including: controlling the gas conditioning device to perform nitrogen replacement with the battery pack to adjust the humidity field of the battery pack; acquiring the real-time humidity value of the battery pack and determining the real-time humidity value as the real-time operating condition data of the battery pack; inputting the real-time operating condition data into a multiphysics coupling model to output the real-time temperature of the material surface in the target area; redetermining the risk level of condensation in the target area based on the dew point temperature and the real-time temperature of the target area; if the redetermined risk level does not meet the preset condensation control conditions of the battery pack, controlling the gas conditioning device to stop the nitrogen replacement operation.

[0110] In the solution provided in this application, when the risk level of condensation on the material surface corresponding to the target area of ​​the battery pack is high, the gas conditioning device can be controlled to perform nitrogen replacement with the battery pack. Simultaneously, a humidity sensor can collect the real-time humidity value of the battery pack. Based on the collected real-time humidity value, a multiphysics coupling model is used to re-determine the risk level of condensation in the target area. When the re-determined risk level becomes medium or low, the gas conditioning device is controlled to stop the nitrogen replacement operation. In this embodiment, when the risk level of condensation in the battery pack is high, the humidity field of the battery pack can be adjusted by the gas conditioning device until the humidity value inside the battery pack is controlled within a reasonable range. Through the cooperation between the multiphysics coupling model and the gas conditioning device, the condensation problem in the battery pack can be improved from the source, which can greatly improve the reliability of the battery pack.

[0111] In some embodiments, the gas regulating device can be connected to the battery management system of the battery pack. This device can not only prevent condensation in the battery pack but also prevent fires by purging with nitrogen in the event of thermal runaway in the battery cells. It is understood that in other embodiments, other dry gases can be introduced into the battery pack through the gas regulating device to replace the humid gases and reduce the humidity of the battery pack.

[0112] Based on the technical solution of the above-described embodiments of this application, a multiphysics coupling model is constructed by combining temperature field-related parameters and humidity field-related parameters. This allows for a quantitative assessment of the probability of condensation occurring in target areas within the battery pack, i.e., determining the risk level of condensation formation on the material surface corresponding to the target area. Consequently, proactive condensation prevention measures can be taken before condensation forms, minimizing the possibility of condensation failure in the battery pack. Furthermore, by implementing the solution of this application, the multiphysics coupling model can accurately assess and quantify the likelihood of condensation occurring in various areas within the battery pack based on the battery pack's operating data, minimizing the risk of condensation formation in blind spots that cannot be visually observed, thus preventing potential safety hazards to the battery pack.

[0113] To better illustrate the condensation control of the battery pack in the foregoing embodiments, this application also provides a refined method for condensation control of the battery pack. Please refer to [link to relevant documentation]. Figure 3 , Figure 3 This is a detailed flowchart illustrating a method for preventing condensation in a battery pack according to some embodiments of this application, which includes the following steps:

[0114] S301. Determine the temperature field model based on relevant temperature field parameters;

[0115] S302. Determine the humidity field model based on relevant parameters of the humidity field;

[0116] S303, Identify the correlation factors between the temperature field model and the humidity field model;

[0117] S304. Embed the quantitative relationship of the correlation factors into the temperature field model and the humidity field model respectively, and determine the bidirectional data interaction logic between the temperature field model and the humidity field model.

[0118] S305. Based on bidirectional data interaction logic, the parameters of the temperature field model and the humidity field model are bidirectionally corrected to obtain a convergent multiphysics coupling model of the battery pack.

[0119] S306. Based on the multiphysics coupling model, the three-dimensional geometric model of the battery pack is meshed using the finite element method to obtain the finite element mesh model.

[0120] In this embodiment, the finite element mesh model includes mesh elements corresponding to each region of the battery pack;

[0121] S307. Load the multiphysics coupling model into the finite element mesh model for simulation processing, obtain the simulation results, and determine the solution coupling model corresponding to each mesh element of the three-dimensional geometric model based on the simulation results.

[0122] In this embodiment, each solution coupling model is used to determine the material surface temperature of the corresponding mesh element under different working conditions;

[0123] S308. Input the initial operating condition data of the battery pack into the solution coupling model corresponding to the target area of ​​the battery pack to obtain the initial temperature of the material surface corresponding to the target area;

[0124] S309. Based on the dew point temperature and initial temperature of the target area, determine the risk level of condensation formation on the material surface corresponding to the target area, and carry out condensation control in the target area according to the risk level.

[0125] Based on the technical solution of the embodiments of this application described above, a temperature field model and a humidity field model are first constructed separately. A multiphysics coupling model of the temperature field model and the humidity field model is then constructed based on the correlation factor effect. The multiphysics coupling model is optimized through mesh generation and numerical simulation to determine the required solution coupling model. While ensuring the accuracy of the model calculations, the computational complexity of the model is minimized as much as possible. Based on the calculation results of the model, the risk level of condensation formation on the material surface inside the battery pack is assessed. Therefore, condensation prevention measures can be proactively taken before condensation forms, minimizing the possibility of condensation failure in the battery pack and preventing condensation formation in blind spots that cannot be visually observed, thus avoiding potential safety hazards to the battery pack.

[0126] It should be understood that the sequence number of each step in this embodiment does not imply the order in which the steps are executed. The execution order of each step should be determined by its function and internal logic, and should not constitute a unique limitation on the implementation process of this application embodiment.

[0127] Based on the same inventive concept, embodiments of this application also provide related products for implementing the above methods. It should be understood that the implementation solutions proposed by the related products for solving the problems are similar to the above methods.

[0128] This application also provides a condensation prevention device for a battery pack. Please refer to... Figure 4 , Figure 4 This is a schematic diagram of the structure of a condensation control device provided in some embodiments of this application. The condensation control device may include a construction module 401, a determination module 402, and a control module 403, as detailed below:

[0129] Module 401 is used to construct a multi-physics coupling model of the battery pack based on the temperature field-related parameters and humidity field-related parameters of the battery pack.

[0130] The determination module 402 is used to input the initial operating condition data of the battery pack into the multiphysics coupling model to obtain the initial temperature of the material surface corresponding to the target area of ​​the battery pack.

[0131] The prevention and control module 403 is used to determine the risk level of condensation formation on the material surface of the target area based on the dew point temperature and initial temperature of the target area, and to carry out condensation prevention and control in the target area according to the risk level.

[0132] In some embodiments, the construction module 401 can be used to: determine a temperature field model based on temperature field related parameters; determine a humidity field model based on humidity field related parameters; and couple the temperature field model and the humidity field model to determine a multi-physics coupling model of the battery pack.

[0133] In some embodiments, the temperature field-related parameters include at least the theoretical operating condition data of the battery pack, the fluid velocity field, and the thermal properties of the materials corresponding to each region within the battery pack. The thermal properties include at least the thermal conductivity, density, and specific heat capacity of the materials. The construction module 401 can also be used to: determine the total heat source term of the first governing equation based on the theoretical operating condition data, wherein the theoretical operating condition data includes the first theoretical heat corresponding to the self-generated heat of the battery pack and the second theoretical heat corresponding to the external heat source, and the total heat source term is the sum of the first theoretical heat and the second theoretical heat; determine the heat conduction term of the first governing equation based on the thermal conductivity; determine the heat convection term of the first governing equation based on the fluid velocity field, density, and specific heat capacity; and determine the temperature field model based on the total heat source term, the heat conduction term, and the heat convection term.

[0134] In some embodiments, the construction module 401 can also be used to: obtain the theoretical operating current and theoretical cell resistance of the battery pack; and determine the first theoretical heat based on the theoretical operating current and theoretical cell resistance of the battery pack.

[0135] In some embodiments, the temperature field related parameters further include a first convective heat transfer coefficient; the construction module 401 can also be used to: determine the first boundary conditions of the temperature field model based on the thermal property parameters and the first convective heat transfer coefficient; and determine the first target output result of the first governing equation based on the first boundary conditions.

[0136] In some embodiments, the humidity field-related parameters include the humidity diffusion coefficient of the battery pack, the fluid velocity field accumulation term, and the humidity source term. The accumulation term is used to indicate the rate of change of humidity over time, and the humidity source term is used to indicate the humidity generation rate or humidity consumption rate of the battery pack per unit volume per unit time. The construction module 401 can also be used to: determine the diffusion term of the second governing equation based on the humidity diffusion coefficient; determine the convective transport term of the second governing equation based on the fluid velocity field; and determine the humidity field model based on the diffusion term, convective transport term, accumulation term, and humidity source term.

[0137] In some embodiments, the humidity field related parameters further include a second convective heat transfer coefficient, and the construction module 401 can also be used to: determine the second boundary conditions of the humidity field model based on the second convective heat transfer coefficient; and determine the second objective output result of the second governing equation based on the second boundary conditions.

[0138] In some embodiments, the construction module 401 can also be used to: identify the correlation factors between the temperature field model and the humidity field model; embed the quantification relationship of the correlation factors into the temperature field model and the humidity field model respectively, and determine the bidirectional data interaction logic between the temperature field model and the humidity field model; and, based on the bidirectional data interaction logic, perform bidirectional correction on the parameters of the temperature field model and the humidity field model to obtain a converged multiphysics coupling model of the battery pack.

[0139] In some embodiments, the construction module 401 can also be used to: perform finite element meshing on the three-dimensional geometric model of the battery pack based on the multiphysics coupling model to obtain a finite element mesh model, wherein the finite element mesh model includes mesh elements corresponding to each region of the battery pack; load the multiphysics coupling model onto the finite element mesh model for simulation processing to obtain simulation results, and determine the solution coupling model corresponding to each mesh element of the three-dimensional geometric model based on the simulation results, wherein each solution coupling model is used to determine the material surface temperature of the corresponding mesh element under different working conditions.

[0140] In some embodiments, the construction module 401 can also be used to: compare the simulation results of the multiphysics coupling model with the actual measurement results of the battery pack to obtain an error comparison result, wherein the simulation results include the simulated temperature of the material surface of each grid cell under full operating conditions, and the actual measurement results include the measured temperature of the material surface of the region corresponding to each grid cell in the battery pack under full operating conditions; and correct the relevant solution coupling model according to the error comparison result to obtain the corrected target solution coupling model, wherein the relevant solution coupling model includes all solution coupling models that cause errors.

[0141] In some embodiments, the prevention and control module 403 can be used to: input the dew point temperature and initial temperature of the target area into a preset condensation probability assessment model to determine the probability of condensation occurring in the target area; and determine the risk level of condensation formation on the material surface corresponding to the target area based on the probability of condensation occurring.

[0142] In some embodiments, the control module 403 can also be used to: obtain the water vapor temperature-humidity ratio and ambient temperature in the environment where the target area is located; and determine the dew point temperature of the target area based on the water vapor temperature-humidity ratio and ambient temperature.

[0143] In some embodiments, the battery pack is connected to a gas conditioning device; the prevention and control module 403 can also be used to: control the gas conditioning device to perform nitrogen replacement with the battery pack to adjust the humidity field of the battery pack; acquire the real-time humidity value of the battery pack and determine the real-time humidity value as the real-time operating condition data of the battery pack; input the real-time operating condition data into a multiphysics coupling model to output the real-time temperature of the material surface in the target area; redetermine the risk level of condensation in the target area based on the dew point temperature and the real-time temperature of the target area; if the redetermined risk level does not meet the preset condensation prevention and control conditions of the battery pack, control the gas conditioning device to stop the nitrogen replacement operation.

[0144] It should be noted that the condensation control methods for battery packs in the foregoing embodiments can all be implemented based on the condensation control device provided in this embodiment. Those skilled in the art can clearly understand that, for the sake of convenience and brevity, the specific working process of the condensation control device described in this embodiment can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0145] Based on the technical solutions of the above embodiments of this application, a multiphysics coupling model is constructed by combining temperature field-related parameters and humidity field-related parameters. This allows for a quantitative assessment of the probability of condensation occurring in target areas within the battery pack, i.e., determining the risk level of condensation formation on the material surface corresponding to the target area. Consequently, proactive condensation prevention measures can be taken before condensation forms, minimizing the possibility of condensation failure in the battery pack. Furthermore, by implementing the solution of this application, the multiphysics coupling model can accurately assess and quantify the likelihood of condensation occurring in various areas within the battery pack based on the battery pack's operating data, minimizing the risk of condensation formation in blind spots that cannot be visually observed, thus preventing potential safety hazards to the battery pack.

[0146] In addition, this application also provides a condensation prevention system for a battery pack. Please refer to [link to relevant documentation]. Figure 5 , Figure 5 This is a schematic diagram of the structure of a battery pack condensation control system provided in some embodiments of this application. The battery pack condensation control system 500 can be used to implement the battery pack condensation control method in the aforementioned embodiments, and mainly includes a processor 501 and a memory 502. The processor 501 and the memory 502 are electrically connected.

[0147] The processor 501 is the control center of the condensation prevention and control system 500 of the battery pack. It connects various parts of the condensation prevention and control system of the entire battery pack through various interfaces and lines. By running or calling the computer program stored in the memory 502, and calling the data stored in the memory 502, it executes various functions of the condensation prevention and control system of the battery pack and processes data, thereby performing overall monitoring of the condensation prevention and control system of the battery pack.

[0148] The memory 502 can be used to store software programs and modules. The processor 501 executes various functional applications and data processing by running the computer programs and modules stored in the memory 502. The memory 502 may mainly include a program storage area and a data storage area. The program storage area may store the operating system, computer programs required for at least one function, etc.; the data storage area may store data created based on the use of the battery pack's condensation prevention system, etc.

[0149] Furthermore, memory 502 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other volatile solid-state storage device. Accordingly, memory 502 may also include a memory controller to provide processor 501 with access to memory 502.

[0150] In this embodiment, the processor 501 in the battery pack condensation prevention system 500 loads the instructions corresponding to the process of one or more computer programs into the memory 502 according to the following steps, and the processor 501 runs the computer programs stored in the memory 502 to realize various functions.

[0151] In some embodiments, the battery pack condensation control system further includes a gas conditioning device communicatively connected to the processor. The gas conditioning device is also connected to the battery pack for nitrogen purging. In this embodiment, when the risk level of condensation in the battery pack is high, the humidity field of the battery pack can be adjusted using the gas conditioning device until the humidity value within the battery pack is controlled within a reasonable range. Through the cooperation between the multiphysics coupling model and the gas conditioning device, the condensation problem in the battery pack can be improved from the source, significantly enhancing the reliability of the battery pack.

[0152] Furthermore, in some embodiments, such as Figure 6As shown, the gas regulating device includes an air compressor 601 and a nitrogen purging unit 602. The input pipeline of the nitrogen purging unit 602 is connected to the air compressor 601, and the output pipeline of the nitrogen purging unit 602 is connected to the nitrogen filling port 6034 of the battery pack 603. The input pipeline can be equipped with a disconnect ball valve 604, and the output pipeline can be equipped with a balance valve 605 and a flow meter 606. The nitrogen purging unit 602 is equipped with components such as a nitrogen rod 6021, a nitrogen dryer 6022, and an air filter 6023. The battery pack 603 can be equipped with components such as a temperature sensor 6031, an oxygen sensor 6032, and a pressure sensor 6033. After the ball valve 604 is opened, the air compressor 601 can input nitrogen into the nitrogen purging unit 602 (for example, the air compressor 601 can be controlled to stably output nitrogen at a pressure of 7 Bar to the nitrogen purging unit 602). In the nitrogen purging unit 602, impurities in the air source can be filtered by the air filter 6023, nitrogen can be separated from the air source by the nitrogen rod 6021, and nitrogen can be dried by the nitrogen dryer 6022, finally outputting dried nitrogen. After the pressure of the dried nitrogen is regulated by the balance valve 605, it enters the battery pack 603 from the nitrogen charging port 6034 under the control of the flow meter 606 (for example, the flow rate is controlled to be 2 L / min). After nitrogen enters the battery pack 603, the displaced air is discharged through the pressure relief port 6035 of the battery pack 603, gradually replacing the internal air and thus reducing the humidity inside the battery pack 603; at the same time, the temperature sensor 6031, oxygen sensor 6032, and pressure sensor 6033 can be used to monitor the internal environment in real time.

[0153] Please refer to Figure 7 This illustration shows a schematic diagram of a computer-readable storage medium provided in an embodiment of this application. The computer-readable storage medium 700 stores program code 701, which can be called by a processor to execute the methods described in the above method embodiments.

[0154] The computer-readable storage medium 700 may be an electronic memory such as flash memory, EEPROM (Electrically Erasable Programmable Read-Only Memory), EPROM, hard disk, or ROM. Optionally, the computer-readable storage medium 700 includes a non-transitory computer-readable storage medium. The computer-readable storage medium 700 has storage space for program code 701 that performs any of the method steps described above. This program code can be read from or written to one or more computer program products. The program code 701 may be compressed, for example, in a suitable form.

[0155] Since the instructions stored in the storage medium can execute the steps in any of the condensation prevention methods for battery packs provided in the embodiments of this application, the beneficial effects that any of the condensation prevention methods for battery packs provided in the embodiments of this application can achieve can be realized. For details, please refer to the previous embodiments, which will not be repeated here.

[0156] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or modules may be electrical, mechanical, or other forms.

[0157] The modules described as separate components may or may not be physically separate. Similarly, the components shown as modules may or may not be physical modules; they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0158] Furthermore, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0159] If the integrated module is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a readable storage medium and includes several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application.

[0160] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0161] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0162] The above is a description of the condensation prevention method, device, system and storage medium for battery packs provided in this application. For those skilled in the art, based on the ideas of the embodiments of this application, there will be changes in the specific implementation and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for preventing condensation in a battery pack, characterized in that, include: Based on the temperature field parameters of the battery pack, a temperature field model is determined; wherein the temperature field parameters include at least the theoretical operating condition data of the battery pack. Based on the humidity field parameters of the battery pack, a humidity field model is determined; The temperature field model and the humidity field model are coupled to determine the multiphysics coupling model of the battery pack. The initial operating condition data of the battery pack is input into the multiphysics coupling model to obtain the initial temperature of the material surface corresponding to the target area of ​​the battery pack. This includes: based on the multiphysics coupling model, performing finite element mesh generation on the three-dimensional geometric model of the battery pack to obtain a finite element mesh model, wherein the finite element mesh model includes mesh elements corresponding to each region of the battery pack; loading the multiphysics coupling model onto the finite element mesh model for simulation processing to obtain simulation results, and determining the solution coupling model corresponding to each mesh element of the three-dimensional geometric model based on the simulation results, wherein each solution coupling model is used to determine the material surface temperature of the corresponding mesh element under different operating conditions. Based on the dew point temperature of the target area and the initial temperature, the risk level of condensation formation on the material surface corresponding to the target area is determined, and condensation prevention and control measures are implemented in the target area according to the risk level.

2. The condensation control method according to claim 1, characterized in that, The temperature field-related parameters also include the fluid velocity field of the battery pack and the thermal properties of the materials corresponding to each region within the battery pack. The thermal properties include at least the thermal conductivity, density, and specific heat capacity of the materials. The step of determining the temperature field model based on the temperature field-related parameters includes: Based on the theoretical operating condition data, the total heat source term of the first control equation is determined, wherein the theoretical operating condition data includes the first theoretical heat corresponding to the self-generated heat of the battery pack and the second theoretical heat corresponding to the external heat source, and the total heat source term is the sum of the first theoretical heat and the second theoretical heat; Based on the thermal conductivity, determine the heat conduction term of the first governing equation; Based on the fluid velocity field, the density, and the specific heat capacity, the thermal convection term of the first governing equation is determined; The temperature field model is determined based on the total heat source term, the heat conduction term, and the heat convection term.

3. The condensation control method according to claim 2, characterized in that, The method further includes: Obtain the theoretical operating current and theoretical cell resistance of the battery pack; The first theoretical heat is determined based on the theoretical operating current and theoretical cell resistance of the battery pack.

4. The condensation control method according to claim 2, characterized in that, The temperature field-related parameters also include the first convective heat transfer coefficient; The method further includes: Based on the aforementioned thermal property parameters and the first convective heat transfer coefficient, the first boundary conditions of the temperature field model are determined. Based on the first boundary condition, the first objective output result of the first governing equation is determined.

5. The condensation control method according to claim 1, characterized in that, The humidity field related parameters include the humidity diffusion coefficient of the battery pack, the fluid velocity field accumulation term, and the humidity source term. The accumulation term is used to indicate the rate of change of humidity over time, and the humidity source term is used to indicate the humidity generation rate or humidity consumption rate of the battery pack per unit volume per unit time. The step of determining the humidity field model based on the humidity field-related parameters includes: Based on the humidity diffusion coefficient, the diffusion term of the second governing equation is determined; Based on the fluid velocity field, the convective transport term of the second governing equation is determined; The humidity field model is determined based on the diffusion term, the convection transport term, the accumulation term, and the humidity source term.

6. The condensation control method according to claim 5, characterized in that, The humidity field-related parameters also include a second convective heat transfer coefficient; the method further includes: Based on the second convective heat transfer coefficient, the second boundary conditions of the humidity field model are determined; Based on the second boundary condition, the second objective output result of the second governing equation is determined.

7. The condensation control method according to claim 1, characterized in that, The process of coupling the temperature field model and the humidity field model to determine the multiphysics coupling model of the battery pack includes: Identify the correlation factors between the temperature field model and the humidity field model; The quantitative relationships of the correlation factors are embedded into the temperature field model and the humidity field model respectively, and the bidirectional data interaction logic between the temperature field model and the humidity field model is determined. Based on the bidirectional data interaction logic, the parameters of the temperature field model and the humidity field model are bidirectionally corrected to obtain a convergent multiphysics coupling model of the battery pack.

8. The condensation control method according to claim 7, characterized in that, The method further includes: The simulation results of the multiphysics coupling model are compared with the actual measurement results of the battery pack to obtain the error comparison results. The simulation results include the simulated temperature of the material surface of each grid cell under full operating conditions, and the actual measurement results include the measured temperature of the material surface of the region corresponding to each grid cell in the battery pack under full operating conditions. The relevant solution coupling model is corrected based on the error comparison results to obtain the corrected target solution coupling model, wherein the relevant solution coupling model includes all the solution coupling models that cause the error.

9. The condensation control method according to claim 1, characterized in that, The determination of the risk level of condensation formation on the material surface corresponding to the target area based on the dew point temperature and the initial temperature of the target area includes: The dew point temperature and the initial temperature of the target area are input into a preset condensation probability evaluation model to determine the probability of condensation occurring in the target area. Based on the probability of condensation occurrence, the risk level of condensation formation on the material surface corresponding to the target area is determined.

10. The condensation control method according to claim 1, characterized in that, The method further includes: Obtain the water vapor temperature-humidity ratio and ambient temperature in the target area; The dew point temperature of the target area is determined based on the water vapor temperature-humidity ratio and the ambient temperature.

11. The condensation control method according to claim 1, characterized in that, The battery pack is connected to the gas regulating device; The step of controlling condensation in the target area according to the risk level includes: The gas conditioning device is controlled to perform nitrogen replacement with the battery pack in order to adjust the humidity field of the battery pack; The real-time humidity value of the battery pack is obtained and the real-time humidity value is determined as the real-time operating condition data of the battery pack. The real-time operating data is input into the multiphysics coupling model to output the real-time temperature of the material surface in the target area; Based on the dew point temperature of the target area and the real-time temperature, the risk level of condensation in the target area is re-determined. If the redefined risk level does not meet the preset condensation control conditions for the battery pack, the gas regulating device is controlled to stop the nitrogen replacement operation.

12. A condensation control device for a battery pack, characterized in that, include: A construction module is used to determine a temperature field model based on the temperature field-related parameters of the battery pack; wherein the temperature field-related parameters include at least the theoretical operating condition data of the battery pack; a humidity field model is determined based on the humidity field-related parameters of the battery pack; and the temperature field model and the humidity field model are coupled to determine the multiphysics coupling model of the battery pack. The determination module is used to input the initial operating condition data of the battery pack into the multiphysics coupling model to obtain the initial temperature of the material surface corresponding to the target area of ​​the battery pack; including: based on the multiphysics coupling model, performing finite element mesh generation on the three-dimensional geometric model of the battery pack to obtain a finite element mesh model, wherein the finite element mesh model includes mesh elements corresponding to each region of the battery pack; loading the multiphysics coupling model into the finite element mesh model for simulation processing to obtain simulation results, and determining the solution coupling model corresponding to each mesh element of the three-dimensional geometric model based on the simulation results, wherein each solution coupling model is used to determine the material surface temperature of the corresponding mesh element under different operating conditions; The prevention and control module is used to determine the risk level of condensation formation on the material surface corresponding to the target area based on the dew point temperature and the initial temperature of the target area, and to carry out condensation prevention and control in the target area according to the risk level.

13. A condensation control system for a battery pack, characterized in that, Including memory and processor, among which, The processor is used to execute a deterministic machine program stored in the memory; When the processor executes the determining machine program, it implements the steps in the condensation control method as described in any one of claims 1 to 11.

14. The condensation control system according to claim 13, characterized in that, It also includes a gas conditioning device that is communicatively connected to the processor, and the gas conditioning device is also connected to the battery pack for nitrogen purging with the battery pack.

15. A deterministic machine-readable storage medium having a deterministic machine program stored thereon, characterized in that, When the determining machine program is executed by the processor, it implements the steps in the condensation control method as described in any one of claims 1 to 11.

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