Charging simulation method and device

Abstract

The invention relates to a charging simulation method and device, and relates to the technical field of batteries, and the method comprises the steps: simulating the charging process of a battery pack based on a battery pack charging simulation model, and detecting the temperature rise data of the battery pack charging simulation model in the simulation charging process; the battery pack charging simulation model comprises a heat conduction assembly in the battery pack; the battery pack charging simulation model is constructed based on thermal characteristic parameters of the battery pack; the thermal characteristic parameters of the battery pack comprise at least one of the following items: a volume heat source of the battery pack and contact thermal resistance between adjacent heat conduction assemblies of the battery pack. Therefore, the heat transfer influence of the heat conduction assembly in the battery pack during charging of the battery pack is considered, the battery pack charging simulation model can truly reflect the heat transfer condition of the heat conduction assembly in the battery pack, and the simulation precision of the battery pack is improved.

Description

Technical Field

[0001] This application relates to the technical field of batteries, in particular to the technical field of battery packs for new energy vehicles, and specifically relates to a charging simulation method and device. Background Art

[0002] With the increasing awareness of environmental protection, new energy vehicles, as a green and sustainable means of transportation, have developed rapidly. As the core component of new energy vehicles, the charging time of the battery pack directly affects the user experience. At the same time, the charging time of the battery pack also directly affects the charging convenience and endurance of new energy vehicles. During the vehicle charging process, charging current, charging voltage, temperature, etc. all affect the charging time of the battery pack. Among them, the influence of temperature on the charging time is particularly important. Therefore, it is necessary to construct a battery pack model to simulate the temperature change during the battery pack charging process, so as to optimize the design of the battery pack and avoid overheating of the battery pack during charging.

[0003] In related technologies, by configuring the thermal material physical property parameters of each component in the three-dimensional geometric model of the battery pack, the heat generation rate of the heat source components of the battery pack is calculated and assigned to the heat source components. And based on the three-dimensional geometric model of the battery pack, the temperature rise data of the battery pack is simulated and solved. In another related technology, the cell simulation parameters in the cell simulation model are corrected. Based on the corrected cell simulation parameters, a battery pack simulation model is configured, and the battery pack is simulated and analyzed and tested under working conditions according to the battery pack simulation model to obtain simulation analysis results and test results, and the battery pack simulation model is corrected, so as to predict the temperature of the battery pack under different working conditions according to the corrected battery pack simulation model. These two methods only consider the influence of the battery cells and heat source components of the battery pack on the temperature rise data of the battery pack, and do not consider the heat transfer influence of the internal components of the battery pack during charging. The battery pack model cannot accurately simulate the charging situation of the battery pack, and the temperature rise data of the battery pack is inaccurate. Summary of the Invention

[0004] The purpose of the embodiments of this application is to provide a charging simulation method and device, aiming to solve the technical problem that the battery pack model in related technologies cannot accurately simulate the charging situation of the battery pack and the temperature rise data of the battery pack is inaccurate.

[0005] In order to achieve the above purpose, the technical solutions adopted in the embodiments of this application are as follows:

[0006] In a first aspect, an embodiment of the present application provides a charging simulation method, which includes: simulating the charging process of a battery pack based on a battery pack charging simulation model, and detecting the temperature rise data of the battery pack charging simulation model during the simulated charging process; the battery pack charging simulation model includes a heat conduction component inside the battery pack; the battery pack charging simulation model is constructed based on the thermal characteristic parameters of the battery pack; the thermal characteristic parameters of the battery pack include at least one of the following: the volume heat source of the battery pack, the contact thermal resistance between adjacent heat conduction components of the battery pack.

[0007] According to the above technical means, the volume heat source of the battery pack and the contact thermal resistance between adjacent heat conduction components of the battery pack can accurately reflect the heat generation capacity and heat generation intensity of the heat conduction components inside the battery pack. By constructing the battery pack charging simulation model based on the volume heat source of the battery pack and the contact thermal resistance between adjacent heat conduction components of the battery pack, the accuracy of the battery pack charging simulation model can be improved. In addition, considering the heat transfer influence of the heat conduction components inside the battery pack during battery pack charging, through the battery pack charging simulation model including the heat conduction components inside the battery pack, the charging process of the battery pack can be realistically simulated, so as to more accurately determine the temperature rise data of the battery pack, in order to optimize the design of the battery pack based on the temperature rise data.

[0008] In a possible implementation manner, the thermal characteristic parameters of the battery pack are determined based on a first simulation model and the physical characteristic parameters of the heat conduction components inside the battery pack.

[0009] According to the above technical means, by adding the heat conduction components inside the battery pack to the first simulation model, the heat transfer influence of the heat conduction components inside the battery pack during battery pack charging is considered when constructing the battery pack charging simulation model. The battery pack charging simulation model can truly reflect the heat transfer situation of the heat conduction components inside the battery pack, improving the simulation accuracy of the battery pack. The battery pack charging simulation model can accurately simulate the temperature rise situation of the battery pack during charging, thus avoiding over-temperature situations when the battery pack is charging.

[0010] In a possible implementation manner, the volume heat source of the battery pack is determined based on the heat generation amount of the heat conduction component, the heat generation amount of the battery cells of the battery pack, and the geometric dimensions of the heat conduction component and the geometric dimensions of the battery cells in the first simulation model; wherein, the heat generation amount of the heat conduction component is determined based on the resistance value of the heat conduction component and the current of the battery pack.

[0011] According to the above technical means, through the heat generation amounts and the geometric dimensions of the heat conduction component and the battery cells, the volume heat source of the battery pack can be accurately determined, thereby improving the accuracy of the battery pack charging simulation model.

[0012] In a possible implementation, the heat generation of the battery cell is determined as follows: By performing electrochemical analysis on the battery model, the heat generation weight coefficients of different heat generation types of the battery cell in different State of Charge (SOC) sections are determined; the heat generation types of the battery cell include at least one of the following: ohmic heat, polarization heat, and side reaction heat; based on the heat and heat generation weight coefficients of different heat generation types of the battery cell, the heat generation of the battery cell is determined.

[0013] According to the above technical means, by performing electrochemical analysis to determine the heat generation weight coefficients of the battery cell in different SOC sections, it can more accurately reflect the temperature change of the battery in different SOC sections. Based on the heat and heat generation weight system of different heat generation types of the battery cell, the heat generation of the battery cell can be accurately determined, thereby improving the accuracy of the charging simulation method.

[0014] In a possible implementation, during the process of simulating the charging of the battery pack based on the battery pack charging simulation model, the volume heat source of the heat conduction component is adjusted according to the detected current and temperature of the battery pack.

[0015] According to the above technical means, based on the current and temperature of the battery pack, dynamically adjusting the volume heat source of the heat conduction component can improve the accuracy and flexibility of the charging simulation method.

[0016] In a possible implementation, the physical property parameters of the heat conduction component include the assembly relationship of the heat conduction component; the contact thermal resistance between adjacent heat conduction components of the battery pack is determined based on the first simulation model and the assembly relationship of the heat conduction component.

[0017] According to the above technical means, by determining the contact thermal resistance between adjacent heat conduction components, the influence of the contact of the heat conduction components on heat transfer is considered, so as to more accurately construct the battery pack charging simulation model.

[0018] In a possible implementation, the contact thermal resistance between adjacent heat conduction components of the battery pack is determined as follows: A third simulation model is constructed based on the assembly relationship of the heat conduction components of the battery pack and the first simulation model; the third simulation model is a simulation model obtained by removing other components in the first simulation model except for the multiple heat conduction components with an interface; the electrochemical analysis is respectively performed on the third simulation model under different working conditions to determine the contact thermal resistance between adjacent heat conduction components of the battery pack under different working conditions; wherein, different working conditions include at least one of the following: different contact pressures between adjacent heat conduction components with an interface, different surface roughnesses of the heat conduction components, and different oxidation degrees of the heat conduction components.

[0019] According to the above technical means, through electrochemical analysis, the contact thermal resistance between adjacent heat conduction components can be accurately determined, improving the accuracy of the battery pack charging simulation model.

[0020] In a possible implementation, the battery pack charging simulation model is constructed as follows: set the volumetric heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack in the first simulation model to obtain the battery pack charging simulation model.

[0021] According to the above technical means, by setting the volumetric heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack in the first simulation model, the battery pack charging simulation model can accurately simulate the charging condition of the battery pack, improving the accuracy of the battery pack temperature rise data.

[0022] In a possible implementation, setting the volumetric heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack in the first simulation model is achieved as follows: configure the volumetric heat source of the battery pack on the heat-conducting components and the battery cells in the first simulation model; wherein, the volumetric heat source is configured in each grid unit of the non-uniform grid of the battery cell, and the non-uniform grid is divided based on the gradient distribution of the electrode thickness of the battery cell; and / or, set the contact thermal resistance between adjacent heat-conducting components of the battery pack at the interface of adjacent heat-conducting components in the first simulation model.

[0023] According to the above technical means, by setting the volumetric heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack in the first simulation model, the battery pack charging simulation model can accurately simulate the heat generation condition of each component during charging of the battery pack and the heat transfer process between components, presenting the internal thermal state of the battery pack more realistically.

[0024] In a possible implementation, the resistance value of the heat-conducting component is determined as follows: perform electrochemical analysis on the first simulation model based on the simulation requirements of the battery pack to obtain the electrochemical parameters of the battery pack; based on the electrochemical parameters of the battery pack, remove other components except the heat-conducting component in the first simulation model to obtain the second simulation model; perform electrochemical simulation on the second simulation model to determine the resistance value of the heat-conducting component.

[0025] According to the above technical means, by removing other components except the heat-conducting component in the first simulation model, the focus of the second simulation model is concentrated on the heat-conducting component. Performing electrochemical simulation on the second simulation model can more accurately determine the resistance value of the heat-conducting component, avoiding the interference of other components, thereby improving the accuracy of the battery pack charging simulation model.

[0026] In a possible implementation, the second simulation model is constructed based on an electromotive force model, a resistance heating model, and an electromagnetic field model.

[0027] Based on the above technical means, a second simulation model is constructed based on the electromotive force mode, the resistance heating model, and the electromagnetic field model, realizing a full-chain simulation from micro to macro, which can more accurately and quickly determine the resistance value of the heat conduction component, thereby improving the accuracy of the battery pack charging simulation model.

[0028] In a possible implementation manner, the heat conduction component includes at least one of the following: copper busbar, aluminum busbar, and aluminum bar.

[0029] Based on the above technical means, by adding a copper busbar, an aluminum busbar, and an aluminum bar to the battery pack charging simulation model, the influence of the heat transfer between the copper busbar, the aluminum busbar, and the aluminum bar on the battery pack charging simulation model is considered, improving the accuracy of the battery pack charging simulation model. Thereby, the accuracy of the temperature rise data simulated by the battery pack charging simulation model when simulating the battery pack charging is improved.

[0030] In a second aspect, an embodiment of the present application provides a charging simulation device, which includes a simulation module and a detection module. The simulation module is used to simulate the charging process of the battery pack based on the battery pack charging simulation model; the detection module is used to detect the temperature rise data of the battery pack charging simulation model during the simulated charging process; the battery pack charging simulation model includes the heat conduction component inside the battery pack; the battery pack charging simulation model is constructed based on the thermal characteristic parameters of the battery pack; the thermal characteristic parameters of the battery pack include at least one of the following: the volume heat source of the battery pack, the contact thermal resistance between adjacent heat conduction components of the battery pack.

[0031] In a possible implementation manner, the thermal characteristic parameters of the battery pack are determined based on the first simulation model and the physical characteristic parameters of the heat conduction component inside the battery pack.

[0032] In a possible implementation manner, the volume heat source of the battery pack is determined based on the heat generation amount of the heat conduction component, the heat generation amount of the battery cells of the battery pack, and the geometric dimensions of the heat conduction component and the geometric dimensions of the battery cells in the first simulation model; wherein, the heat generation amount of the heat conduction component is determined based on the resistance value of the heat conduction component and the current of the battery pack.

[0033] In a possible implementation manner, the heat generation amount of the battery cell is determined by the following method: by performing electrochemical analysis on the battery model, determining the heat generation weight coefficients of different heat generation types of the battery cell in different state of charge (SOC) sections; the heat generation types of the battery cell include at least one of the following: ohmic heat, polarization heat, and side reaction heat; based on the heat amounts and heat generation weight coefficients of different heat generation types of the battery cell, determining the heat generation amount of the battery cell.

[0034] In some embodiments, during the process of simulating the charging process of the battery pack based on the battery pack charging simulation model, the volume heat source of the heat conduction component is adjusted according to the detected current and temperature of the battery pack.

[0035] In a possible implementation, the physical property parameters of the heat conduction component include the assembly relationship of the heat conduction component; the contact thermal resistance between adjacent heat conduction components of the battery pack is determined based on the first simulation model and the assembly relationship of the heat conduction component.

[0036] In a possible implementation, the contact thermal resistance between adjacent heat conduction components of the battery pack is determined as follows: constructing a third simulation model based on the assembly relationship of the heat conduction components of the battery pack and the first simulation model; the third simulation model is a simulation model obtained by removing other components in the first simulation model except for the multiple heat conduction components with interfaces; respectively performing electrochemical analysis on the third simulation model under different working conditions to determine the contact thermal resistance between adjacent heat conduction components of the battery pack under different working conditions; where the different working conditions include at least one of the following: different contact pressures between adjacent heat conduction components with interfaces, different surface roughnesses of the heat conduction components, and different oxidation degrees of the heat conduction components.

[0037] In a possible implementation, the battery pack charging simulation model is constructed as follows: setting the volume heat source of the battery pack and / or the contact thermal resistance between adjacent heat conduction components of the battery pack in the first simulation model to obtain the battery pack charging simulation model.

[0038] In a possible implementation, configuring the volume heat source of the battery pack on the heat conduction component and the battery cell in the first simulation model; where the volume heat source is configured in each grid unit of the non-uniform grid of the battery cell, and the non-uniform grid is divided based on the gradient distribution of the electrode thickness of the battery cell; and / or, setting the contact thermal resistance between adjacent heat conduction components of the battery pack at the interface between adjacent heat conduction components in the first simulation model.

[0039] In a possible implementation, the resistance value of the heat conduction component is determined as follows: performing electrochemical analysis on the first simulation model based on the simulation requirements of the battery pack to obtain the electrochemical parameters of the battery pack; based on the electrochemical parameters of the battery pack, removing other components in the first simulation model except for the heat conduction component to obtain a second simulation model; performing electrochemical simulation on the second simulation model to determine the resistance value of the heat conduction component.

[0040] In a possible implementation, the second simulation model is constructed based on the electromotive force model, the resistance heating model, and the electromagnetic field model.

[0041] In a possible implementation, the heat conduction component includes at least one of the following: copper busbar, aluminum busbar, aluminum bar.

[0042] In a third aspect, an embodiment of the present application provides an electronic device, which includes: a processor and a memory for storing processor-executable instructions; wherein, the processor is configured to execute instructions to implement the charging simulation method of any of the above embodiments.

[0043] Fourthly, an embodiment of the present application provides a computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the charging simulation method of any of the above embodiments is implemented.

[0044] Fifthly, an embodiment of the present application provides a computer program product, which includes computer program instructions. When the computer program instructions are executed by a processor, the charging simulation method of any of the above embodiments is implemented.

[0045] It should be noted that for the technical effects brought by any implementation manner in the second to fifth aspects, reference may be made to the technical effects brought by the corresponding implementation manner in the first aspect, which will not be elaborated here.

[0046] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The drawings here are incorporated into the specification and form a part of this specification, showing the embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application, and do not constitute an improper limitation to the present application.

[0048] Figure 1 is a flowchart of a charging simulation method shown according to an exemplary embodiment;

[0049] Figure 2 is a flowchart of constructing a charging simulation model of a battery pack shown according to an exemplary embodiment;

[0050] Figure 3 is a schematic structural diagram of a first simulation model shown according to an exemplary embodiment;

[0051] Figure 4 is a schematic structural diagram of an aluminum bar shown according to an exemplary embodiment;

[0052] Figure 5 is a schematic structural diagram of a copper bar (aluminum bar) shown according to an exemplary embodiment;

[0053] Figure 6 is a flowchart of another method for constructing a charging simulation model of a battery pack shown according to an exemplary embodiment;

[0054] Figure 7 is a schematic structural diagram of heat conduction components overlapping each other shown according to an exemplary embodiment;

[0055] Figure 8 is a schematic diagram of the contact between a copper bar and an aluminum bar shown according to an exemplary embodiment;

[0056] Figure 9 is a flowchart of yet another method for constructing a battery pack charging simulation model shown according to an exemplary embodiment;

[0057] Figure 10 is a flowchart of yet another method for constructing a battery pack charging simulation model shown according to an exemplary embodiment;

[0058] Figure 11 is a flowchart of a method for determining the resistance value of a heat conducting component shown according to an exemplary embodiment;

[0059] Figure 12 is a schematic diagram of copper bars (aluminum bars) with different structures shown according to an exemplary embodiment;

[0060] Figure 13 is a schematic diagram of aluminum bars with different structures shown according to an exemplary embodiment;

[0061] Figure 14 is a flowchart of yet another method for constructing a battery pack charging simulation model shown according to an exemplary embodiment;

[0062] Figure 15 is a block diagram of a charging simulation device shown according to an exemplary embodiment;

[0063] Figure 16 is a block diagram of an electronic device shown according to an exemplary embodiment. Detailed implementation manners

[0064] In order to enable those of ordinary skill in the art to better understand the technical solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0065] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that such used data may be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order different from those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0066] In the present application, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, article or device including the element.

[0067] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0068] As mentioned in the background technology, the current charging methods of new energy vehicle battery packs can be roughly divided into DC fast charging and AC slow charging. Among them, the factors that affect the simulation of the DC fast charging time of the battery pack include the type of battery pack, charging current, charging voltage, temperature, etc. The influence of temperature on charging time is particularly important. In the battery pack bench test, due to the high temperature of the thermal conductive component of the battery pack, the temperature is transferred to the battery cell, resulting in frequent over-temperature of the battery cell and pole at the connection with the thermal conductive component of the battery pack. Therefore, it is necessary to simulate the temperature changes of the battery pack during charging by constructing a battery pack model and optimize the design of the battery pack to avoid this phenomenon.

[0069] In the related art, the modeling method of the battery pack is mostly numerical simulation, which simulates the temperature rise of the battery pack during charging by building a three-dimensional model of the battery pack. The three-dimensional model of the battery pack includes the upper cover, box, bottom plate, cold plate, battery module, etc. However, since the thermal conductive components inside the battery pack are not built in the three-dimensional model of the battery pack, the simulation results are inaccurate when the charging process of the battery pack is simulated based on the three-dimensional model of the battery pack, and the temperature rise of the battery cells at the connection of the thermal conductive components cannot be accurately simulated. In addition, when the finite element model of the battery pack in the related art simulates the connection of the components in the battery pack, it only simulates the contact between the pole ear and the air domain in the battery pack, and does not consider the influence of the thermal conductive components in the battery pack. When calculating the heat transfer of the components in the battery pack, the pole ear and the air in the battery pack directly exchange heat, which does not meet the actual engineering problems. In addition, most of the related technologies use heat transfer models to simulate the actual overcurrent state of the battery pack, focusing more on the cell level or system level, without considering independent modeling for specific components, and without subdividing the modeling objects, resulting in low accuracy of battery pack simulation.

[0070] In view of this, the present application provides a charging simulation method, which simulates the charging process of a battery pack based on a battery pack charging simulation model, and detects the temperature rise data of the battery pack charging simulation model during the simulated charging process; the battery pack charging simulation model includes a heat conduction component inside the battery pack. It can be seen that the present application takes into account the heat transfer effect of the heat conduction component inside the battery pack during charging. By using the battery pack charging simulation model that includes the heat conduction component inside the battery pack, the charging process of the battery pack can be realistically simulated, so as to more accurately determine the temperature rise data of the battery pack, and optimize the design of the battery pack based on the temperature rise data.

[0071] For ease of understanding, the charging simulation method provided by the present application will be specifically introduced below with reference to the accompanying drawings.

[0072] In some embodiments, the execution subject of the charging simulation method provided by the embodiments of the present application can be any one of the following: a server cluster composed of multiple servers, a single server, a computer, a server, or a processor or processing chip in a computer, etc., which can perform charging simulation, and the embodiments of the present application do not limit this.

[0073] Figure 1 is a flowchart of a charging simulation method shown according to an exemplary embodiment. As Figure 1 shown, the charging simulation method includes the following steps:

[0074] S101. Simulate the charging process of the battery pack based on the battery pack charging simulation model.

[0075] Among them, the battery pack charging simulation model includes a heat conduction component inside the battery pack.

[0076] In some embodiments, the heat conduction component includes at least one of the following: a copper busbar, an aluminum busbar, and an aluminum bar.

[0077] In some embodiments, the battery pack charging simulation model is constructed based on the thermal characteristic parameters of the battery pack. Among them, the thermal characteristic parameters of the battery pack are determined based on the first simulation model and the physical characteristic parameters of the heat conduction component inside the battery pack; the first simulation model includes the heat conduction component inside the battery pack.

[0078] In some embodiments, the thermal characteristic parameters of the battery pack include at least one of the following: the volume heat source of the battery pack, the contact thermal resistance between adjacent heat conduction components of the battery pack.

[0079] In some embodiments, the physical characteristic parameters of the heat conduction component include at least one of the following: the resistance value of the heat conduction component, the assembly relationship of the heat conduction component.

[0080] As a possible implementation, when the physical characteristic parameters of the heat conduction component include the resistance value of the heat conduction component, the volumetric heat source of the battery pack is determined based on the first simulation model and the resistance value of the heat conduction component.

[0081] Exemplarily, the volumetric heat source of the battery pack is determined based on the heat generation of the heat conduction component, the heat generation of the battery cells of the battery pack, and the geometric dimensions of the heat conduction component and the battery cells in the first simulation model; wherein, the heat generation of the heat conduction component is determined based on the resistance value of the heat conduction component and the current of the battery pack.

[0082] It should be noted that the heat generation of the battery cell can be determined in the following way: by performing electrochemical analysis on the battery model, determining the heat generation weight coefficients of different heat generation types of the battery cell in different State of Charge (SOC) sections; based on the heat and heat generation weight coefficients of different heat generation types of the battery cell, determining the heat generation of the battery cell.

[0083] Wherein, the heat generation types of the battery cell include at least one of the following: ohmic heat, polarization heat, and side reaction heat.

[0084] As a possible implementation, during the process of simulating the charging of the battery pack based on the battery pack charging simulation model, the volumetric heat source of the heat conduction component is adjusted according to the detected current and temperature of the battery pack.

[0085] As a possible implementation, when the physical characteristic parameters of the heat conduction component include the assembly relationship of the heat conduction component, the contact thermal resistance between adjacent heat conduction components of the battery pack is determined based on the first simulation model and the assembly relationship of the heat conduction component.

[0086] Exemplarily, the contact thermal resistance between adjacent heat conduction components of the battery pack is determined by the following method: constructing a third simulation model based on the assembly relationship of the heat conduction components of the battery pack and the first simulation model; the third simulation model is a simulation model obtained by removing other components in the first simulation model except for the multiple heat conduction components with an interface; performing electrochemical analysis on the third simulation model under different working conditions respectively to determine the contact thermal resistance between adjacent heat conduction components of the battery pack under different working conditions.

[0087] Wherein, different working conditions include at least one of the following: different contact pressures between adjacent heat conduction components with an interface, different surface roughnesses of the heat conduction components, and different oxidation degrees of the heat conduction components.

[0088] In some embodiments, the battery pack charging simulation model is constructed by the following method: setting the volumetric heat source of the battery pack and / or the contact thermal resistance between adjacent heat conduction components of the battery pack in the first simulation model to obtain the battery pack charging simulation model.

[0089] Exemplarily, setting the volumetric heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack in the first simulation model is achieved in the following manner: configuring the volumetric heat source of the battery pack on the heat-conducting components and the battery cells in the first simulation model; and / or, setting the contact thermal resistance between adjacent heat-conducting components of the battery pack at the interface of adjacent heat-conducting components in the first simulation model.

[0090] Among them, the volumetric heat source is configured in each grid unit of the non-uniform grid of the battery cell, and the non-uniform grid is divided based on the gradient distribution of the electrode thickness of the battery cell.

[0091] In some embodiments, the resistance value of the heat-conducting component can be determined in the following manner: performing electrochemical analysis on the first simulation model based on the simulation requirements of the battery pack to obtain the electrochemical parameters of the battery pack; based on the electrochemical parameters of the battery pack, removing other components except the heat-conducting component in the first simulation model to obtain a second simulation model; performing electrochemical simulation on the second simulation model to determine the resistance value of the heat-conducting component.

[0092] Exemplarily, the second simulation model is constructed based on the electromotive force model, the resistance heating model, and the electromagnetic field model.

[0093] It can be understood that the above battery pack charging simulation model pays more attention to the heat transfer between the busbar (aluminum bar), the aluminum tab, the terminal post, and the battery cell, and the heat transfer of the key components of the battery pack. By simulating the charging process of the battery pack through the above battery pack charging simulation model, the accuracy of the charging simulation analysis can be improved.

[0094] It should be noted that in the construction of the battery pack simulation model based on the busbar, aluminum bar, and aluminum tab in the related art, the heat-conducting component is usually regarded as an ideal conductor, only paying attention to the electrical conductivity of the heat-conducting component, or the heat-conducting component is simplified to a homogeneous material to simplify the heat conduction path.

[0095] However, from the perspective of the Joule heat effect, as high-current conductors, the busbar and the tab, the Joule heat generated by the resistance of the heat-conducting component is one of the main heat sources of the battery pack. If the heat-conducting component is directly ignored, the simulation results of the battery pack cannot accurately reflect the temperature rise situation of the battery pack. From the perspective of the heat conduction path, the thermal conductivity of the busbar, aluminum bar, and aluminum tab is much higher than that of other components in the battery pack. Therefore, the busbar, aluminum bar, and aluminum tab can accelerate the transfer of heat in the battery pack to the connection parts such as the battery cell tab.

[0096] In addition, if the heat conduction component is not properly designed, local hot spots may be formed in the battery pack, thus affecting the safety of the battery pack. Therefore, the heat conduction component needs to be included in the first simulation model. The battery pack charging simulation model provided by the embodiments of the present application combines the electrical conductivity and heat conductivity of the heat conduction component, and more realistically simulates the simulation model of the battery pack during the charging process. The battery pack charging simulation model provided by the embodiments of the present application accurately simulates the heat generation process and heat transfer process of the heat conduction component, can more realistically reflect the temperature rise situation during the battery pack charging process, and can significantly improve the accuracy of the battery pack charging simulation model. Based on this, the battery pack charging simulation method provided by the embodiments of the present application can not only issue a warning before the battery pack overheats and gets out of control, but also provide an optimization basis for the heat dissipation design of the battery pack, improving the safety and reliability during the battery pack charging process.

[0097] It can be understood that the battery pack charging simulation method provided by the embodiments of the present application effectively simulates the heat transfer path of the heat conduction component by performing a thermodynamic analysis on the battery pack charging simulation model in advance and setting the volume heat source and contact thermal resistance, improves the accuracy of the battery pack charging simulation model, and simulates the complete temperature rise situation of the battery cell during the early simulation process. Whether the battery cell exceeds the temperature rise threshold can be found during the simulation process, avoiding the risk of the battery cell overheating in the bench test, and effectively reducing the R & D cycle and R & D cost.

[0098] Exemplarily, the construction process of the above battery pack charging simulation model can refer to the following steps S201 - S203, which will not be elaborated here.

[0099] S102. Detect the temperature rise data of the battery pack charging simulation model during the simulated charging process.

[0100] It can be understood that the charging simulation method provided by the embodiments of the present application takes into account the heat transfer influence of the heat conduction component inside the battery pack during battery pack charging. Through the battery pack charging simulation model including the heat conduction component inside the battery pack, the charging process of the battery pack under different working conditions can be realistically simulated, so as to more accurately obtain the temperature rise data of the battery pack charging simulation model during the simulated charging process, timely discover the over-temperature situation of the battery pack and prevent it, avoid the over-temperature situation in the bench test of the battery pack, and reduce the R & D cycle and R & D cost of the battery pack.

[0101] The construction of the battery pack charging simulation model will be specifically introduced below.

[0102] In some embodiments, the battery pack charging simulation model is constructed based on the thermal characteristic parameters of the battery pack, such as Figure 2 shown, and can be specifically implemented as the following steps:

[0103] S201. Obtain the first simulation model of the battery pack.

[0104] Among them, the first simulation model includes the internal heat conduction components of the battery pack. The heat conduction components include at least one of the following: copper busbar, aluminum busbar, and aluminum tab.

[0105] In some embodiments, the first simulation model of the battery pack can be constructed by obtaining the simulation data of each component of the battery pack and the simulation requirements of the battery pack. Among them, the simulation requirements are the process requirements of the battery pack and the operating conditions requirements of the battery pack. The operating conditions requirements represent various types of operating conditions problems that occur when the battery pack is in normal use. The first simulation model can be a three-dimensional model in the computer-aided design (CAD) format of the battery pack, or a planar model containing the dimensional data of each component of the battery pack.

[0106] In some embodiments, each component of the battery pack can be determined based on the actual application scenario of the battery pack and the type of the battery pack.

[0107] It should be noted that in the thermodynamics principle of the battery pack, after the copper busbar, aluminum busbar, and aluminum tab generate heat, the heat is transferred to adjacent components through heat transfer for heat dissipation. The components adjacent to the copper busbar, aluminum busbar, and aluminum tab are the pole column and the battery cell, resulting in an increase in the temperature rise data of the pole column and the battery cell. The heat dissipation of the copper busbar, aluminum busbar, and aluminum tab affects the simulation of the battery cell heating in the battery pack. The method for constructing the battery pack charging simulation model of the present application can truly simulate the heating situation of the battery pack by adding the copper busbar, aluminum busbar, and aluminum tab to the first simulation model, so as to accurately simulate the charging duration of the battery pack.

[0108] Figure 3 is a schematic structural diagram of a first simulation model shown according to an exemplary embodiment, as Figure 3 shown, the first simulation model includes a top cover 301, a copper busbar (aluminum busbar) 302, a battery cell 303, a frame 304, an aluminum tab 305, and a pole column 306. The positional relationship between the components of the battery pack is as Figure 3 shown.

[0109] Figure 4 is a schematic structural diagram of an aluminum tab 305 shown according to an exemplary embodiment, as Figure 4 shown, there are various aluminum tabs 305 with different structures in the battery pack.

[0110] Figure 5 is a schematic structural diagram of a copper busbar (aluminum busbar) 302 shown according to an exemplary embodiment, as Figure 5 shown, there are three copper busbars (aluminum busbars) 302 with different structures in the battery pack.

[0111] S202. Determine the thermal characteristic parameters of the battery pack based on the first simulation model and the physical characteristic parameters of the heat conduction components.

[0112] Among them, the thermal characteristic parameters of the battery pack include at least one of the following: the volumetric heat source of the battery pack, and the contact thermal resistance between adjacent heat-conducting components of the battery pack.

[0113] It should be noted that from the above Figure 4 and Figure 5 it can be seen that the battery pack includes various aluminum bars with different structures and various copper bars (aluminum bars) with different structures. Therefore, the battery pack includes multiple heat-conducting components.

[0114] In some embodiments, the components that generate heat in the battery pack can be determined according to the first simulation model and the physical characteristic parameters of the heat-conducting components, and the calorific value of the heat-generating components can be calculated to determine the volumetric heat source of the battery pack.

[0115] It should be noted that the copper bars, aluminum bars, and aluminum bars have electrical conductivity, and the calorific value of the heat-conducting components can be calculated by calculating the resistance values of the copper bars, aluminum bars, and aluminum bars to determine the volumetric heat source of the battery pack.

[0116] In some embodiments, based on the resistance values of multiple heat-conducting components, the calorific value of each heat-conducting component can be calculated respectively. And the calorific value of other heat-generating components in the battery pack can be determined, such as the calorific value of the battery cells. Thus, based on the calorific value of each heat-conducting component, the calorific value of other heat-generating components, and the size information of the heat-generating components in the first simulation model, the volumetric heat source of the battery pack can be calculated.

[0117] It should be noted that the volumetric heat source represents the heat generated by a unit volume of an object per unit time, and the unit is W / m 3 . In the battery pack, the volumetric heat source is used to reflect the heat generation ability and heat generation intensity of each component inside the battery pack.

[0118] In some embodiments, the contact thermal resistance between adjacent heat-conducting components of the battery pack can be determined by performing electrochemical analysis on the first simulation model according to the physical characteristic parameters of multiple heat-conducting components.

[0119] S203. Construct a battery pack charging simulation model based on the thermal characteristic parameters of the battery pack.

[0120] In some embodiments, based on the thermal characteristic parameters of the battery pack, the volumetric heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack can be set in the first simulation model to obtain a battery pack charging simulation model.

[0121] It should be understood that by setting the volume heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack in the first simulation model in the method for constructing a battery pack charging simulation model of the present application, the internal heat transfer path of the battery pack can be effectively simulated, and the simulation accuracy of the battery pack can be improved. Based on the battery pack charging simulation model, the temperature rise situation of the battery pack during charging can be accurately simulated, the over-temperature situation of the battery pack can be detected in time and prevented, the over-temperature situation in the bench test of the battery pack can be avoided, and the R & D cycle and R & D cost of the battery pack are reduced.

[0122] In some embodiments, the physical property parameters of the heat-conducting components include the resistance value of the heat-conducting components and / or the assembly relationship of the heat-conducting components. As Figure 6 shown, the above step S202 can be specifically implemented through the following steps S2021 and / or S2022:

[0123] S2021. Construct a third simulation model based on the assembly relationship of the heat-conducting components of the battery pack and the first simulation model.

[0124] In a possible implementation manner, based on the assembly relationship of the heat-conducting components of the battery pack, the interfaces between multiple heat-conducting components are determined. There may be multiple interfaces between multiple heat-conducting components. For each interface, a third simulation model including only the heat-conducting components constituting the interface can be established based on the first simulation model.

[0125] S2022. Perform electrochemical analysis on the third simulation model under different working conditions to determine the contact thermal resistance between adjacent heat-conducting components of the battery pack under different working conditions.

[0126] In some embodiments, based on the assembly relationship of the heat-conducting components of the battery pack, electrochemical analysis is performed on the first simulation model to determine the contact thermal resistance between adjacent heat-conducting components of the battery pack.

[0127] In a possible implementation manner, based on the physical parameters of the heat-conducting components, the contact properties of the interface, such as the friction coefficient, contact stiffness, etc., are set in the third simulation model. Electrochemical analysis is performed on the third simulation model to simulate the heat transfer process between the heat-conducting components constituting the interface, and the contact thermal resistance corresponding to the interface is calculated. Thus, the contact thermal resistance corresponding to each interface, that is, the contact thermal resistance between adjacent heat-conducting components of the battery pack, is calculated.

[0128] It should be noted that there are few interfaces where the copper busbar (aluminum busbar) and the aluminum bar are in complete contact. The gaps between the non-contact interfaces between the copper busbar (aluminum busbar) and the aluminum bar are often filled with air, and heat is conducted through this air gap layer. Compared with the completely contact solid surface, this situation increases the additional transfer resistance, and this additional resistance is the contact thermal resistance. By determining the contact thermal resistance between adjacent heat-conducting components of the battery pack, the temperature rise situation of the copper busbar (aluminum busbar) conducting to the aluminum bar can be truly simulated.

[0129] Figure 7 It is a schematic diagram showing the overlapping structure of heat-conducting components according to an exemplary embodiment. As Figure 7 shown, the heat-conducting components include aluminum bars 305 and copper bars (aluminum bars) 302. In the battery pack, there are situations where multiple heat-conducting components overlap to generate contact surfaces.

[0130] Figure 8 It is a schematic diagram showing the contact between a copper bar and an aluminum bar according to an exemplary embodiment. As Figure 8 shown, the copper bar 801 and the aluminum bar 802 are in contact with each other to generate an interface 803.

[0131] In some embodiments, as Figure 9 shown, the above step S2021 can be specifically implemented through the following steps S2021a - S2021b:

[0132] S2021a. Calculate the heat generation of the heat-conducting component based on the resistance value of the heat-conducting component and the current of the battery pack.

[0133] In some embodiments, the heat generation of each heat-conducting component in multiple heat-conducting components can be calculated based on the resistance value of each heat-conducting component and the current of the battery pack, in combination with the Joule's law formula. Among them, the current of the battery pack is the current input when the battery pack charging simulation model simulates the battery pack charging process. The magnitude of the current can be set according to simulation requirements and actual situations, and the current is used to characterize the allowable charging current magnitude of the battery cells in the battery pack under different temperatures and states of charge (SOC).

[0134] S2021b. Determine the volume heat source of the battery pack based on the heat generation of the heat-conducting component, the heat generation of the battery cells of the battery pack, and the geometric dimensions of the heat-conducting component and the battery cells in the first simulation model.

[0135] In some embodiments, the heat generation of the battery cells of the battery pack can be calculated through the internal resistance value of the battery cells and the current of the battery pack.

[0136] It should be noted that the internal resistance value of the battery cell changes with temperature and SOC. When the temperature decreases, the viscosity of the electrolyte inside the battery cell increases, the ion diffusion resistance increases, and the internal resistance value of the battery cell rises. When the temperature increases, the ion activity inside the battery cell enhances, and the internal resistance value of the battery cell decreases. Under different SOC states, the electrochemical state inside the battery is different, and the internal resistance value of the battery cell will also fluctuate. When the SOC value is at a relatively low level, for example, the SOC value is less than 20%, the quantity of active substances inside the battery cell is relatively small, and the internal resistance value of the battery cell rises. When the SOC value is at a medium level, for example, the SOC value is between 20% - 80%, the active substances inside the battery cell can participate in the electrochemical reaction more fully, the internal resistance value of the battery cell is relatively stable, and the internal resistance value of the battery cell is lower. When the SOC value is at a relatively high level, for example, the SOC value is close to 100%, the concentration of the electrolyte inside the battery cell changes, and the internal resistance value of the battery cell rises.

[0137] In some embodiments, the volume of each heat - generating component inside the battery pack, that is, the volume of the heat - conducting component and the volume of the battery cell, can be calculated respectively based on the geometric dimensions of the heat - conducting component and the geometric dimensions of the battery cell in the first simulation model. And the volume heat source of the battery pack is calculated based on the following expression (1):

[0138]

[0139] Wherein, q represents the volume heat source of the battery pack. Q represents the heat generation quantity of the heat - conducting component and the heat generation quantity of the battery cell of the battery pack. V represents the volume of the heat - conducting component and the volume of the battery cell of the battery pack. Δt represents the heat - generating duration of the battery pack.

[0140] In some embodiments, the heat generation quantity of the battery cell can be determined in the following manner: by performing electrochemical analysis on the battery model, determining the heat generation weight coefficients of different heat - generating types of the battery cell in different state - of - charge (SOC) sections; and determining the heat generation quantity of the battery cell based on the heat quantity and heat generation weight coefficients of different heat - generating types of the battery cell.

[0141] Exemplarily, the heat - generating types of the battery cell include at least one of the following: ohmic heat, polarization heat, and side - reaction heat.

[0142] Among them, ohmic heat is used to represent the heat generated when electrons and ions encounter resistance during movement in the battery cell when current passes through the internal resistance of the battery cell. For example, ohmic heat can be determined by Ohm's law (I 2 R).

[0143] Polarization heat is used to represent the energy loss caused by the uneven distribution of charges on the electrode surface (polarization phenomenon) during the electrochemical reaction process, which is released in the form of heat. For example, polarization heat can be determined based on the dynamic RC model.

[0144] The side reaction heat is used to represent the heat generated by unexpected electrochemical reactions (such as electrolyte decomposition, electrode material corrosion, etc.) occurring inside the battery cell. For example, the side reaction heat is the electrochemical heat generation based on the Arrhenius equation.

[0145] It should be noted that the heat generation weight coefficient can be determined in the following way: By adjusting the parameters of the battery model, simulating the operating states of the battery cell in different SOC sections, calculating the heat generation amounts of different heat generation types in each SOC section according to the output of the battery model, comparing the heat generation amounts of different heat generation types with the total heat generation amount, and determining the heat generation weight coefficient.

[0146] It can be understood that in the field of heat source settings of the battery pack, most of the related technologies assume that the heat source inside the battery pack is uniform, adopt a homogenized heat source distribution in the battery pack simulation model, consider that the heat generation inside the battery cell is uniform, do not consider that there are differences in the heat generation rates of different regions inside the battery cell under different SOC states, only use the ohmic internal resistance to calculate the heat generation, cannot accurately reflect the heat generation process of the battery cell, and the related technologies rely on static parameters, and the heat source parameters of the heat conduction components used are mostly fixed values based on the laboratory standard working conditions, without considering the dynamic influence of factors such as temperature and battery pack aging on the heat source parameters during the actual discharge process of the battery pack.

[0147] In addition, when building the battery pack simulation model, the related technologies simplify the heat coupling path inside the battery pack, only focus on the heat generation of the battery cell body, and ignore the heat generation due to the contact resistance at the joints of the copper busbars and aluminum bars. The battery pack simulation model usually regards the connectors of the copper busbars and aluminum bars as ideal conductors, and this assumption has a large deviation from the actual situation.

[0148] Based on this, when calculating the heat generation amount of the battery cell in the embodiments of the present application, starting from the multi-level heat generation perspective of the battery cell, the heat generation types of the battery cell are divided into ohmic heat, polarization heat and side reaction heat. Through electrochemical analysis, the heat generation weight coefficient in different SOC sections is determined, and a battery pack charging simulation model is established in combination with spatial heterogeneity (that is, there are differences in the heat generation rates of different regions inside the battery cell).

[0149] In some embodiments, during the process of simulating the charging of the battery pack based on the battery pack charging simulation model, the volume heat source of the heat conduction component is adjusted according to the detected current and temperature of the battery pack.

[0150] It should be noted that through the dynamic feedback compensation mechanism, according to the detected current and temperature of the battery pack in real time, the volume heat source of the heat conduction component is dynamically adjusted, so that the battery pack charging simulation model can more accurately reflect the charging process of the battery pack.

[0151] In some embodiments, such as Figure 10As shown, the above step S203 can be specifically implemented through the following steps S2031 and / or S2032:

[0152] S2031. Configure the volume heat source of the battery pack on the heat conduction component and the battery cell in the first simulation model.

[0153] Among them, the volume heat source is configured in each grid unit of the non-uniform grid of the battery cell, and the non-uniform grid is divided based on the gradient distribution of the electrode thickness of the battery cell.

[0154] It should be noted that based on the gradient distribution of the internal electrode thickness of the battery cell (such as the design of thick edges and thin middle), the battery cell is divided into non-uniform grids, and the volume heat source of the battery cell is determined based on the volume heat source in each grid unit of the non-uniform grid divided based on the battery cell, so as to accurately simulate the formation mechanism of local hot spots of the battery cell during the actual operation of the battery pack.

[0155] In some embodiments, the material properties of the heat conduction component and the battery cell, such as density, specific heat capacity, thermal conductivity, etc., can be set in the first simulation model. And specify the heat generating components in the first simulation model, namely the copper bar (aluminum bar), aluminum tab and battery cell. Input the volume heat source of the battery pack into the corresponding component settings in the first simulation model.

[0156] S2032. Set the contact thermal resistance between adjacent heat conduction components of the battery pack on the interface between adjacent heat conduction components in the first simulation model.

[0157] In some embodiments, perform computational fluid dynamics (CFD) mesh division on the first simulation model to determine the position of the interface between adjacent heat conduction components in the first simulation model. Set the corresponding contact thermal resistance at the position of the interface in the first simulation model.

[0158] It should be understood that a copper bar (aluminum bar) and an aluminum tab are built in the first simulation model. And calculate the heat generation amount through the resistance of the copper bar (aluminum bar) and the aluminum tab and assign it to the volume heat source. By setting the contact thermal resistance of the copper bar (aluminum bar) and the aluminum tab, the real temperature rise situation from the copper bar (aluminum bar) to the aluminum tab to the terminal post and finally connecting to the battery cell can be truly simulated.

[0159] In some embodiments, the contact thermal resistance is used to represent the introduction of additional transfer resistance at the interface between the copper bar (aluminum bar) and the aluminum tab. At the interface between the copper bar (aluminum bar) and the aluminum tab, the actual contact between the copper bar (aluminum bar) and the aluminum tab only occurs on some discrete area elements (i.e., the microscopic discrete areas where the copper bar and the aluminum tab actually make physical contact), and the actually non-contact interface is filled with a medium (such as air). The heat generated by the heat conduction component is conducted through the medium. Compared with the completely contact interface, the above-mentioned interface between the copper bar (aluminum bar) and the aluminum tab will introduce additional transfer resistance, that is, the contact thermal resistance.

[0160] It should be noted that the existence of contact thermal resistance can make the heat transfer process between heat conduction components more complex, thus increasing the difficulty of simulating heat transfer. However, the setting of contact thermal resistance is crucial for truly reflecting the temperature rise situation in the heat transfer process between heat conduction components. In the embodiments of the present application, the contact thermal resistance between adjacent heat conduction components is determined based on bench tests.

[0161] Exemplarily, by designing multi-variable coupling experiments such as contact pressure, surface roughness, oxidation degree, etc., the characteristic curves of contact thermal resistance under different working conditions are obtained, and a dynamic mapping relationship between contact thermal resistance and pressure parameters is established.

[0162] It can be understood that through the dynamic mapping relationship between the contact thermal resistance and pressure parameters obtained by bench tests, the contact thermal resistance between adjacent heat conduction components can be obtained more accurately. Through the contact thermal resistance, the thermal conductivity between adjacent heat conduction components can be obtained more accurately, thus significantly improving the accuracy of the battery pack charging simulation model.

[0163] In addition, the contact thermal resistance determined by bench tests can also be used to reverse calibrate the battery pack charging simulation model and optimize the influence of multi-variables such as contact pressure, surface roughness, oxidation degree, etc. on the contact thermal resistance.

[0164] In some embodiments, as Figure 11 shown, the resistance value of the above-mentioned heat conduction component can be determined through the following steps S1101 - S1103:

[0165] S1101. Perform electrochemical analysis on the first simulation model based on the simulation requirements of the battery pack to obtain the electrochemical parameters of the battery pack.

[0166] S1102. Based on the electrochemical parameters of the battery pack, remove other components in the first simulation model except the heat conduction component to obtain the second simulation model.

[0167] In some embodiments, for each of the multiple heat conduction components, the first simulation model can be lap-jointed based on the electrochemical parameters of the battery pack. Retain the key components, that is, the heat conduction component. Remove other components in the first simulation model except the heat conduction component to obtain the second simulation model corresponding to the heat conduction component.

[0168] Figure 12 is a schematic diagram of a copper bar (aluminum bar) with a different structure shown according to an exemplary embodiment. As Figure 12 shown, there are three different structures of copper bars (aluminum bars) 1201, copper bar (aluminum bar) 1202, and copper bar (aluminum bar) 1203 in the battery pack.

[0169] Figure 13Schematic diagram of aluminum bars with different structures shown according to an exemplary embodiment, as Figure 13 shown, there are six aluminum bars with different structures in the battery pack: aluminum bar 1301, aluminum bar 1302, aluminum bar 1303, aluminum bar 1304, aluminum bar 1305, and aluminum bar 1306.

[0170] It should be noted that, in combination with the above Figure 12 and Figure 13 , the interior of the battery pack includes multiple heat-conducting components with different structures. For each heat-conducting component with a specific structure, a corresponding second simulation model can be constructed. Therefore, there are also multiple second simulation models.

[0171] It should also be noted that the lapping process is an operation for optimizing and integrating the model structure and component relationships. Based on the electrochemical analysis results, according to the physical structure, electrical connection, and heat conduction relationship of the battery pack, each component in the first simulation model is reorganized, adjusted, and screened to obtain the second simulation model.

[0172] S1103. Conduct electrochemical simulation on the second simulation model to determine the resistance value of the heat-conducting component.

[0173] In some embodiments, electrochemical simulation can be performed on the second simulation model to determine the conduction situation of the heat-conducting component in the battery pack under specific current conditions, so as to determine the resistance value of the heat-conducting component.

[0174] A possible implementation method, in combination with the above Figure 12 , corresponding second simulation models can be established for three different structures of copper bars (aluminum bars) respectively and electrochemical simulation analysis can be performed on each of them to determine the resistance value of each structure of copper bar (aluminum bar).

[0175] Another possible implementation method, in combination with the above Figure 13 , corresponding second simulation models can be established for six different structures of aluminum bars respectively and electrochemical simulation analysis can be performed on each of them to determine the resistance value of each structure of aluminum bar.

[0176] It should be understood that by simplifying the battery pack components in the first simulation model that do not participate in thermodynamic conduction, the second simulation model can be obtained more accurately. Accurately simulate the conductivity and heat transfer of the heat-conducting component, truly reflect the heat conduction relationship of the battery pack, and improve the calculation accuracy of the resistance value of the heat-conducting component.

[0177] In some embodiments, the second simulation model is constructed based on the electromotive force model, resistance heating model, and electromagnetic field model.

[0178] A possible implementation is that the electromotive force model can accurately capture the potential distribution of the battery pack during the electrochemical process. Combining with the heat generation mechanism of the battery pack (such as irreversible heat or reversible heat, etc.), the electromotive force model can dynamically analyze the ohmic resistance and diffusion resistance generated by the polarization effect inside the battery cell, and is especially suitable for SOC (state of charge) / power interpolation simulation in power battery thermal management.

[0179] Another possible implementation is that the resistance heating model directly quantifies the Joule heat effect through the coupling calculation of the current density inside the battery cell and the conductivity of the heat conduction component. The resistance heating model supports the input of real physical property parameters (such as density related to temperature, specific heat capacity polynomial), so as to accurately evaluate the thermal coupling relationship between the temperature rise and internal resistance of the components inside the battery pack under complex working conditions.

[0180] Yet another possible implementation is that the electromagnetic field model can simulate the action of magnetic fields on conductive fluids or solid materials (such as molten metals, plasmas). Combining with the magnetic vector potential solver and multi-physics coupling capabilities, the electromagnetic field model can analyze the influence of electromagnetic forces, Lorentz forces, etc. on the internal resistance distribution of the battery pack, and is especially suitable for scenarios such as motor cooling, transformers, etc.

[0181] It should be noted that in related technologies, when calculating the resistance value of the heat conduction component, empirical formula simplification, static equivalent circuit or single physical field analysis are usually adopted. However, the above methods have certain limitations and cannot comprehensively and dynamically reflect the complex relationship between the resistance value of the heat conduction component and various physical factors.

[0182] Based on this, the battery pack charging simulation model provided in the embodiments of the present application adopts an electro-thermal coupling iteration method, dynamically predicts the resistance value of the heat conduction component based on multi-physics coupling, integrates the electromotive force model, resistance heating model and electromagnetic field model in the simulation software, and establishes a second simulation model related to temperature and current frequency inside the heat conduction component.

[0183] Figure 14 It is a flowchart showing yet another construction of a battery pack charging simulation model according to an exemplary embodiment, as Figure 14 shown, and includes the following steps:

[0184] S1401. Obtain the first simulation model of the battery pack, where the first simulation model includes the heat conduction component inside the battery pack.

[0185] S1402. Conduct an electrochemical analysis on the first simulation model, construct a second simulation model corresponding to the heat conduction component, and calculate the resistance value of the heat conduction component.

[0186] S1403. Calculate the heat generation amount of the heat conduction component according to the resistance value of the heat conduction component, and calculate the volume heat source of the battery pack.

[0187] S1404. Calculate the contact thermal resistance between adjacent heat conduction components according to the assembly relationship between adjacent heat conduction components.

[0188] S1405. Set the volume heat source of the battery pack and the contact thermal resistance between adjacent heat conduction components in the first simulation model to obtain a battery pack charging simulation model.

[0189] The above mainly introduces the solution provided by the embodiments of the present application from the perspective of methods. To implement the above functions, the charging simulation device or electronic device includes corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should easily realize that, combining the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed in the way of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present application.

[0190] The embodiments of the present application can, according to the above method, exemplarily divide the functional modules of the charging simulation device or electronic device. For example, the charging simulation device or electronic device can include respective functional modules corresponding to each functional division, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiments of the present application is illustrative, only a logical functional division, and there can be other division methods in actual implementation.

[0191] Figure 15 is a block diagram of a charging simulation device shown according to an exemplary embodiment. Refer to Figure 15 , the charging simulation device 1500 includes: a simulation module 1501 and a detection module 1502.

[0192] The simulation module 1501 is used to simulate the charging process of the battery pack based on the battery pack charging simulation model; the detection module 1502 is used to detect the temperature rise data of the battery pack charging simulation model during the simulated charging process; the battery pack charging simulation model includes heat conduction components inside the battery pack; the battery pack charging simulation model is constructed based on the thermal characteristic parameters of the battery pack; the thermal characteristic parameters of the battery pack include at least one of the following: the volume heat source of the battery pack, the contact thermal resistance between adjacent heat conduction components of the battery pack. In a possible implementation manner, the thermal characteristic parameters of the battery pack are determined based on the first simulation model and the physical characteristic parameters of the heat conduction components inside the battery pack.

[0193] In a possible implementation, the volumetric heat source of the battery pack is determined based on the heat generation of the heat conducting component, the heat generation of the battery cells of the battery pack, and the geometric dimensions of the heat conducting component and the battery cells in the first simulation model; wherein, the heat generation of the heat conducting component is determined based on the resistance value of the heat conducting component and the current of the battery pack.

[0194] In a possible implementation, the heat generation of the battery cells is determined by the following method: by performing an electrochemical analysis on the battery model, determining the heat generation weight coefficients of different heat generation types of the battery cells in different state of charge (SOC) sections; the heat generation types of the battery cells include at least one of the following: ohmic heat, polarization heat, and side reaction heat; based on the heat amounts and heat generation weight coefficients of different heat generation types of the battery cells, determining the heat generation of the battery cells.

[0195] In some embodiments, during the simulation of the charging process of the battery pack based on the battery pack charging simulation model, the volumetric heat source of the heat conducting component is adjusted according to the detected current and temperature of the battery pack.

[0196] In a possible implementation, the physical property parameters of the heat conducting component include the assembly relationship of the heat conducting component; the contact thermal resistance between adjacent heat conducting components of the battery pack is determined based on the first simulation model and the assembly relationship of the heat conducting component.

[0197] In a possible implementation, the contact thermal resistance between adjacent heat conducting components of the battery pack is determined by the following method: constructing a third simulation model based on the assembly relationship of the heat conducting components of the battery pack and the first simulation model; the third simulation model is a simulation model obtained by removing other components in the first simulation model except for the multiple heat conducting components with interfaces; performing an electrochemical analysis on the third simulation model under different working conditions respectively to determine the contact thermal resistance between adjacent heat conducting components of the battery pack under different working conditions; wherein, different working conditions include at least one of the following: different contact pressures between adjacent heat conducting components with interfaces, different surface roughnesses of the heat conducting components, and different oxidation degrees of the heat conducting components.

[0198] In a possible implementation, the battery pack charging simulation model is constructed by the following method: setting the volumetric heat source of the battery pack and / or the contact thermal resistance between adjacent heat conducting components of the battery pack in the first simulation model to obtain the battery pack charging simulation model.

[0199] In a possible implementation, the volumetric heat source of the battery pack is configured on the heat conducting component and the battery cells in the first simulation model; wherein, the volumetric heat source is configured in each grid unit of the non-uniform grid of the battery cells, and the non-uniform grid is divided based on the gradient distribution of the electrode thickness of the battery cells; and / or, the contact thermal resistance between adjacent heat conducting components of the battery pack is set on the interface between adjacent heat conducting components in the first simulation model.

[0200] In a possible implementation, the resistance value of the heat-conducting component is determined in the following manner: Electrochemical analysis is performed on the first simulation model based on the simulation requirements of the battery pack to obtain the electrochemical parameters of the battery pack; based on the electrochemical parameters of the battery pack, other components in the first simulation model except the heat-conducting component are removed to obtain a second simulation model; electrochemical simulation is performed on the second simulation model to determine the resistance value of the heat-conducting component.

[0201] In a possible implementation, the second simulation model is constructed based on an electromotive force model, a resistance heating model, and an electromagnetic field model.

[0202] In a possible implementation, the heat-conducting component includes at least one of the following: copper busbar, aluminum busbar, aluminum bar.

[0203] According to the above technical means, through a battery pack charging simulation model including the internal heat-conducting component of the battery pack, the charging process of the battery pack can be truly simulated. Thus, the temperature rise data of the battery pack can be determined more accurately, so as to optimize the design of the battery pack based on the temperature rise data.

[0204] Regarding the device in the above embodiments, the specific manners in which each module performs operations have been described in detail in the embodiments related to the method, and will not be elaborated herein.

[0205] Figure 16 is a block diagram of an electronic device shown according to an exemplary embodiment. As Figure 16 shown, the electronic device 1600 includes but is not limited to: a processor 1601 and a memory 1602.

[0206] Among them, the above-mentioned memory 1602 is used to store the executable instructions of the above-mentioned processor 1601. It can be understood that the above-mentioned processor 1601 is configured to execute instructions to implement the charging simulation method in the above embodiments.

[0207] It should be noted that those skilled in the art can understand that Figure 16 the structure of the electronic device shown in Figure 16 does not constitute a limitation on the electronic device, and the electronic device may include more or fewer components than

[0208] The processor 1601 is the control center of the electronic device, connecting various parts of the entire electronic device through various interfaces and circuits. By running or executing software programs and / or modules stored in the memory 1602, and by invoking the data stored in the memory 1602, it executes various functions of the electronic device and processes data, thereby monitoring the electronic device as a whole. The processor 1601 may include one or more processing units. Optionally, the processor 1601 may integrate an application processor and a modem processor. Among them, the application processor mainly processes the operating system, user interface, application programs, etc., and the modem processor mainly processes wireless communication. It can be understood that the above-mentioned modem processor may not be integrated into the processor 1601 either.

[0209] The memory 1602 can be used to store software programs and various data. The memory 1602 mainly includes a program storage area and a data storage area. Among them, the program storage area can store the operating system, application programs required by at least one functional module (such as a determination unit, a processing unit, etc.). In addition, the memory 1602 may include high-speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, or other non-volatile solid-state storage devices.

[0210] In an exemplary embodiment, there is also provided a computer-readable storage medium including instructions, such as the memory 1602 including instructions. The above instructions can be executed by the processor 1601 of the electronic device 1600 to implement the charging simulation method in the above embodiment.

[0211] In actual implementation, Figure 15 the functions of the simulation module 1501 and the detection module 1502 in Figure 16 can both be implemented by the processor 1601 in

[0212] invoking the computer programs stored in the memory 1602. The specific execution process can refer to the description of the method part in the above embodiment, and will not be elaborated here.

[0213] In an exemplary embodiment, the embodiment of the present application also provides a computer program product including one or more instructions. The one or more instructions can be executed by the processor 1601 of the electronic device to complete the charging simulation method in the above embodiment.

[0214] It should be noted that when one or more instructions in the above-mentioned computer-readable storage medium or in the computer program product are executed by the processor of the electronic device, the various processes of the above-mentioned method embodiments are implemented, and the same technical effects as those of the above-mentioned method can be achieved. To avoid repetition, details are not described here again.

[0215] From the description of the above embodiments, those skilled in the art can clearly understand that for the convenience and brevity of description, only the above division of each functional module is used as an example. In actual applications, the above functions can be allocated to different functional modules according to needs, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0216] In several embodiments provided in the present application, it should be understood that the disclosed device and method can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of modules or units is only a logical functional division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be through some interfaces. The indirect coupling or communication connection of the device or unit can be in electrical, mechanical or other forms.

[0217] The units described as separate components may or may not be physically separated. The components displayed as units may be one physical unit or multiple physical units, that is, they may be located in one place, or they may be distributed to multiple different places. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0218] In addition, each functional unit in the various embodiments of the present application can be integrated in one processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0219] When an integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of the embodiments of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions for causing a device (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute all or part of the steps of the methods of the various embodiments of the present application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, ROM, RAM, magnetic disks, or optical discs that can store program codes.

[0220] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A charging simulation method, characterized in that: The charging simulation method comprises: The charging process of the battery pack is simulated based on a battery pack charging simulation model, and the temperature rise data of the battery pack charging simulation model during the simulated charging process is detected; the battery pack charging simulation model includes a heat-conducting component inside the battery pack; the battery pack charging simulation model is constructed based on the thermal characteristic parameters of the battery pack; the thermal characteristic parameters of the battery pack include at least one of the following: the volume heat source of the battery pack, and the contact thermal resistance between adjacent heat-conducting components of the battery pack.

2. The charging simulation method according to claim 1, characterized in that: The thermal characteristic parameters of the battery pack are determined based on a first simulation model and physical characteristic parameters of a heat-conducting component inside the battery pack.

3. The charging simulation method according to claim 2, characterized in that: The volume heat source of the battery pack is determined based on the heat generated by the heat conductive component, the heat generated by the battery cell of the battery pack, and the geometric dimensions of the heat conductive component and the geometric dimensions of the battery cell in the first simulation model; wherein the heat generated by the heat conductive component is determined based on the resistance value of the heat conductive component and the current of the battery pack.

4. The charging simulation method according to claim 3, characterized in that: The calorific value of the battery cell is determined by: By performing electrochemical analysis on the battery model, determining the heat generation weight coefficients of different heat generation types of the battery cell in different state of charge (SOC) sections; the heat generation type of the battery cell includes at least one of the following: ohmic heat, polarization heat and side reaction heat; The calorific value of the battery cell is determined based on the heat of different heat generating types of the battery cell and the heat generating weight coefficient.

5. The charging simulation method according to claim 3, characterized in that: In a process of simulating the charging of a battery pack based on the battery pack charging simulation model, the volume heat source of the heat conductive component is adjusted according to the detected current and temperature of the battery pack.

6. The charging simulation method according to claim 2, characterized in that: The physical characteristic parameters of the heat-conducting components include the assembly relationship of the heat-conducting components; the contact thermal resistance between adjacent heat-conducting components of the battery pack is determined based on the first simulation model and the assembly relationship of the heat-conducting components.

7. The charging simulation method according to claim 4, characterized in that: The contact thermal resistance between adjacent heat-conducting components of the battery pack is determined by: A third simulation model is constructed based on the assembly relationship of the heat-conducting components of the battery pack and the first simulation model; the third simulation model is a simulation model obtained by eliminating other components in the first simulation model except for the multiple heat-conducting components with interfaces; Electrochemical analysis is performed on the third simulation model under different working conditions to determine the contact thermal resistance between adjacent thermally conductive components of the battery pack under different working conditions; wherein the different working conditions include at least one of the following: different contact pressures between adjacent thermally conductive components at interfaces, different surface roughnesses of thermally conductive components, and different degrees of oxidation of thermally conductive components.

8. The charging simulation method according to claim 2, characterized in that: The battery pack charging simulation model is constructed in the following way: The volume heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack are set in the first simulation model to obtain the battery pack charging simulation model.

9. The charging simulation method according to claim 8, characterized in that: Setting the volume heat source of the battery pack and / or the contact thermal resistance between adjacent heat-conducting components of the battery pack in the first simulation model is achieved in the following manner: Arrange a volume heat source of the battery pack on the heat-conducting components and the battery cells in the first simulation model; wherein the volume heat source is arranged in each grid unit of the non-uniform grid of the battery cells, and the non-uniform grid is divided based on the gradient distribution of the electrode thickness of the battery cells; and / or, A contact thermal resistance between adjacent heat-conducting components of the battery pack is set on the interface between adjacent heat-conducting components in the first simulation model.

10. The charging simulation method according to claim 3, characterized in that: The resistance value of the thermally conductive component is determined by: Performing electrochemical analysis on the first simulation model based on the simulation requirements of the battery pack to obtain electrochemical parameters of the battery pack; Based on the electrochemical parameters of the battery pack, other components except the heat conductive component in the first simulation model are eliminated to obtain a second simulation model; Performing electrochemical simulation on the second simulation model to determine the resistance value of the heat conducting component.

11. The charging simulation method according to claim 10, characterized in that: The second simulation model is constructed based on the electromotive force model, the resistance heating model and the electromagnetic field model.

12. The charging simulation method according to any one of claims 1 to 11, characterized in that: The heat-conducting component includes at least one of the following: a copper busbar, an aluminum busbar, and an aluminum bar.

13. A charging simulation device, characterized in that: The charging simulation device comprises: a simulation module and a detection module; The simulation module is used to simulate the charging process of the battery pack based on the battery pack charging simulation model; The detection module is used to detect the temperature rise data of the battery pack charging simulation model during the simulated charging process; the battery pack charging simulation model includes a thermal conductive component inside the battery pack; the battery pack charging simulation model includes a thermal conductive component inside the battery pack; the battery pack charging simulation model is constructed based on the thermal characteristic parameters of the battery pack; the thermal characteristic parameters of the battery pack include at least one of the following: the volume heat source of the battery pack, and the contact thermal resistance between adjacent thermal conductive components of the battery pack.

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