Battery cell temperature calculation method and device, equipment and storage medium

Abstract

The embodiment of the invention discloses a cell temperature calculation method and device, equipment and a storage medium, and the method comprises the steps: obtaining the initial temperature of a target control body for the target control body in a plurality of control bodies; the target control body is any one of the plurality of control bodies; according to the initial temperature of the target control body and heat information in the target calculation period, the temperature of the target control body after the target calculation period is finished is determined, and the heat information in the target calculation period comprises heat exchange between the target control body and the target object in the target calculation period and heat generated by the target control body; the target object comprises at least one of an external environment where the battery cell is located, an adjacent control body and a temperature adjusting device; according to the temperatures of the multiple control bodies after the target calculation period is finished, temperature information of the battery cell after the target calculation period is finished is determined, and the temperature information comprises the highest temperature and / or the lowest temperature. The accuracy of temperature calculation can be improved.

Description

Technical Field

[0001] The embodiments of the present application relate to vehicle battery management technology, including but not limited to a method and device for calculating the temperature of battery cells, equipment, and storage media. Background Art

[0002] To ensure the safety of vehicle batteries, it is usually necessary to calculate the temperature of the batteries, for example, calculate the current temperature of the batteries or predict the temperature after a period of time.

[0003] In related technologies, the commonly adopted solution is usually to use the temperature collected by sensors as the real-time temperature or perform temperature prediction based on the temperature collected by sensors. However, since the temperature distribution is not uniform during the operation of the batteries, the temperature collected by sensors may not be accurate, which may lead to errors in temperature calculation. Summary of the Invention

[0004] The method and device for calculating the temperature of battery cells, equipment, and storage media provided by the embodiments of the present application are implemented as follows:

[0005] On the one hand, an embodiment of the present application provides a method for calculating the temperature of battery cells, which is applied to a battery management system in a vehicle. The vehicle includes battery cells, and the battery cells include a plurality of pre-divided control bodies. The method includes:

[0006] For a target control body among the plurality of control bodies, obtain the initial temperature of the target control body; the target control body is any one of the plurality of control bodies;

[0007] According to the initial temperature of the target control body and the heat information within a target calculation period, determine the temperature of the target control body after the end of the target calculation period. The heat information within the target calculation period includes: the heat exchanged between the target control body and a target object within the target calculation period and its own heat generation. The target object includes at least one of the external environment where the battery cell is located, adjacent control bodies, and a temperature control device;

[0008] According to the temperatures of the plurality of control bodies after the end of the target calculation period, determine the temperature information of the battery cell after the end of the target calculation period. The temperature information includes the highest temperature and / or the lowest temperature.

[0009] On the other hand, an embodiment of the present application further provides a device for calculating the temperature of battery cells, which is applied to a battery management system in a vehicle. The vehicle includes battery cells, and the battery cells include a plurality of pre-divided control bodies. The device includes: an acquisition module, a calculation module, and a result module;

[0010] The acquisition module is used to obtain the initial temperature of a target control body for a target control body among the plurality of control bodies; the target control body is any one of the plurality of control bodies;

[0011] A calculation module, configured to determine the temperature of a target control volume after the end of a target calculation period according to the initial temperature of the target control volume and the heat information within the target calculation period, where the heat information within the target calculation period includes: the heat exchanged between the target control volume and a target object within the target calculation period and the heat generated by itself, and the target object includes at least one of the external environment where the battery cell is located, an adjacent control volume, and a temperature control device;

[0012] A result module, configured to determine the temperature information of the battery cell after the end of the target calculation period according to the temperatures of multiple control volumes after the end of the target calculation period, where the temperature information includes the highest temperature and / or the lowest temperature.

[0013] The computer device provided by an embodiment of the present application includes a memory and a processor. The memory stores a computer program that can run on the processor, and when the processor executes the program, the method of the embodiment of the present application is implemented.

[0014] The computer-readable storage medium provided by an embodiment of the present application stores a computer program thereon, and when the computer program is executed by a processor, the method provided by the embodiment of the present application is implemented.

[0015] In the battery cell temperature calculation method, device, equipment, and storage medium provided by the embodiments of the present application, for a target control volume among multiple control volumes, the initial temperature of the target control volume can be obtained; according to the initial temperature of the target control volume and the heat information within the target calculation period, the temperature of the target control volume after the end of the target calculation period can be determined; and then, according to the temperatures of multiple control volumes after the end of the target calculation period, the temperature information of the battery cell after the end of the target calculation period can be determined. Among them, by dividing the battery cell into multiple target control volumes, the temperature of each area in the battery cell can be determined more accurately, and then the temperature of the battery cell can be calculated based on the temperature of each target control volume, which can improve the accuracy of battery cell temperature calculation. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0017] Figure 1 It is a schematic diagram of the battery cell structure provided by an embodiment of the present application;

[0018] Figure 2 It is a schematic flowchart of the battery cell temperature calculation method provided by an embodiment of the present application;

[0019] Figure 3Schematic diagram of the structure of each control body in the battery cell provided in the embodiments of the present application;

[0020] Figure 4 Another flowchart of the battery cell temperature calculation method provided in the embodiments of the present application;

[0021] Figure 5 Another flowchart of the battery cell temperature calculation method provided in the embodiments of the present application;

[0022] Figure 6 Schematic diagram of the interface for displaying the current temperature of the battery cell provided in the embodiments of the present application;

[0023] Figure 7 Schematic diagram of the interface for displaying the temperature change curve of the battery cell provided in the embodiments of the present application;

[0024] Figure 8 Schematic diagram of the structure of the battery cell temperature calculation device provided in the embodiments of the present application;

[0025] Figure 9 Schematic diagram of the structure of the computer device provided in the embodiments of the present application. Detailed implementation manners

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will further describe the specific technical solutions of the present application in detail with reference to the accompanying drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application but are not intended to limit the scope of the present application.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0028] In the following descriptions, reference is made to "some embodiments", which describe a subset of all possible embodiments. However, it can be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0029] It should be noted that the terms "first / second / third" involved in the embodiments of the present application are used to distinguish similar or different objects and do not represent a specific order for the objects. It can be understood that "first / second / third" can be interchanged with a specific order or sequence when allowed, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0030] During the operation of the battery management system of a vehicle, in order to control the vehicle in a timely manner, for example, cooling or heating the battery during charging, it is usually necessary to obtain the temperature of the battery, which can be the current temperature of the battery or the predicted temperature after a period of time.

[0031] In the related art, the commonly adopted solution is to use the temperature collected by the sensor for temperature calculation. However, since the temperature distribution of the battery is not uniform during operation, the temperature collected by the sensor may not be accurate. If the temperature calculation is based on the temperature collected by the sensor during the operation of the battery, there may be errors in the temperature calculation. For example, an incorrect real-time temperature may be obtained, or an incorrect predicted temperature may be obtained, etc.

[0032] In order to solve the problems existing in the related art, an electrode core temperature calculation method is provided in the embodiments of the present application. Next, the hardware structure of the electrode core provided in the embodiments of the present application will be explained.

[0033] Figure 1 The schematic diagram of the electrode core structure provided in the embodiments of the present application is shown in Figure 1 , Figure 1 The content shown is a cross-sectional view of the electrode core. The electrode core is divided into multiple control bodies. Among them, Figure 1 it is explained by taking 10 control bodies as an example. In the actual implementation process, other division methods can also be adopted according to actual needs or the battery structure, and it is not limited by the division method shown in Figure 1 .

[0034] Among them, the electrode core includes: an electrode core body, an upper shell, and positive and negative electrode posts. In Figure 1 , the electrode core body is divided into four control bodies, that is, Figure 1 the control bodies 1-4 in Figure 1 ; the upper shell is divided into four control bodies, that is,

[0035] the control bodies 5-8 in

[0036] ; the positive and negative electrode posts are control bodies 9 and 10 respectively.

[0037] Among them, during the process of temperature reduction, the temperature adjustment medium can be a coolant, and the temperature of the battery cell is reduced by the low temperature of the coolant; during the process of heating, the temperature adjustment medium can be a heating liquid, and the temperature of the battery cell is increased by the high temperature of the heating liquid.

[0038] It should be noted that during the process of dividing the battery cell, the dimensions of each control volume can be recorded, such as: the side length, area, etc. of each face of each control volume, and the adjacency relationship of each control volume can be recorded, such as: Figure 1 For the control volume 3 in, it is adjacent to the control volume 1 on the upper side, adjacent to the control volume on the right side, adjacent to the temperature adjustment device on the lower side, and adjacent to the external environment on the remaining sides.

[0039] Next, based on the above structure of the battery cell, the implementation process of the battery cell temperature calculation method provided in the embodiments of the present application will be explained.

[0040] Figure 2 For the flow schematic diagram of the battery cell temperature calculation method provided in the embodiments of the present application, please refer to Figure 2 , a battery cell temperature calculation method, including:

[0041] S210: For a target control volume among multiple control volumes, obtain the initial temperature of the target control volume.

[0042] It should be noted that the execution subject of this method can be the battery management system (BMS, Battery Management System) of the vehicle, and the battery cell can be the battery cell in the battery set on the vehicle. The battery cell can be pre-divided into multiple control volumes, such as Figure 1 The battery cell structure shown in can be divided into 10 control volumes, where the target control volume is any one of the multiple control volumes.

[0043] In one embodiment, the division of multiple control volumes can be carried out according to actual needs, can be carried out according to the circuit structure in the battery cell, or can be carried out according to calculation needs. The division method is not limited herein.

[0044] Among them, the target control volume can be Figure 1 Any one of the control volumes shown in, such as: control volume 3.

[0045] The initial temperature of the target control volume can be the temperature of the target control volume before temperature calculation. For example: if it is a calculation before charging, it can be the temperature when not charged; if it is a calculation before work, it can be the temperature when the battery starts to supply power to the vehicle; if it is a real-time calculation, it can be the temperature at the start of the calculation.

[0046] It should be noted that if the battery is neither charged nor working, it can be determined that the battery is in a state with a uniform temperature distribution. In this case, the temperature collected by the temperature sensor set at control volume 7 is the temperature of each control volume in the battery cell; if the battery is working or being charged, it can be determined that the battery is in a state with a non-uniform temperature distribution. In this case, the temperature collected by the temperature sensor set at control volume 7 can only represent the temperature of control volume 7.

[0047] If the initial temperature corresponds to the temperature when the battery is not charged or not working, the temperature collected by the temperature sensor can be used as the initial temperature. If the initial temperature corresponds to the temperature when the battery is working or being charged, the temperature obtained from the previous calculation can be used as the initial temperature.

[0048] S220: Determine the temperature of the target control volume at the end of the target calculation period based on the initial temperature of the target control volume and the heat information during the target calculation period.

[0049] It should be noted that after obtaining the initial temperature of the target control volume, temperature calculation can be performed based on the initial temperature of the target control volume and the heat information during the target calculation period.

[0050] In one embodiment, the target calculation period can be the period for temperature calculation, and the duration of this period can be set according to actual needs and will not be specifically limited here.

[0051] The target calculation period can include a step size and the number of iterations. Among them, the step size refers to the prediction duration corresponding to the result of each iteration, and the number of iterations refers to the number of times of temperature calculation within this target calculation period.

[0052] For example: If the temperature calculation is real-time calculation, the step size in the target calculation period can be equal to the calculation duration of this calculation period, and the number of iterations can be one; if the temperature calculation is for predicting future temperature, the step size in the target calculation period can be greater than the calculation duration of this calculation period, and the number of iterations can be multiple.

[0053] For example: If the calculation duration of the vehicle's BMS in the target calculation period is 0.1 s, during real-time calculation, the step size can be 0.1 s and the number of iterations can be 1 time. In this way, the determination of real-time temperature can be achieved; during the prediction of future temperature, the step size can be 2 s and the number of iterations can be 24 times. In this way, the prediction of the temperature 48 s later can be achieved.

[0054] It should be noted that the heat information during the target calculation period includes: the heat exchanged between the target control volume and the target object and the heat generated by itself during the target calculation period.

[0055] Among them, the target object includes at least one of the external environment where the battery cell is located, adjacent control volumes, and the temperature control device.

[0056] The external environment where the battery cell is located refers to the external space where the battery is located; the adjacent control volume can be other control volumes adjacent to the target control volume. For example, for Figure 1 control volume 3 in, its adjacent control volumes can be control volume 1 and control volume 4; the temperature control device can be the aforementioned temperature control device for outputting coolant or heating liquid.

[0057] Among them, the exchanged heat refers to the heat exchange situation between the target control volume and the adjacent target object. If the temperature of the target control volume is greater than the temperature of the target object, the heat exchange can be a decrease in heat; if the temperature of the target control volume is less than the temperature of the target object, the heat exchange can be an increase in heat. The self-generated heat can be the heat generated by the internal circuit of the target control volume during operation.

[0058] The temperature of the target control volume after the target calculation period ends refers to the temperature of the target control volume obtained after the target calculation period is calculated. Among them, if the moment after the target calculation period ends is equal to the current moment, or the difference between the moment after the target calculation period ends and the current moment is less than or equal to the preset threshold, the temperature of the target control volume at this moment can be used as the real-time temperature; if the moment after the target calculation period ends is greater than the current moment, or the difference between the moment after the target calculation period ends and the current moment is greater than the preset threshold, the temperature of the target control volume at this moment can be used as the predicted temperature.

[0059] S230: Determine the temperature information of the battery cell after the target calculation period ends according to the temperatures of multiple control volumes after the target calculation period ends.

[0060] It should be noted that for any target control volume, the scheme of S220 can be used to calculate the temperature after the target calculation period ends; during the calculation of the real-time temperature, for Figure 1 the temperature of control volume 7 in, since the temperature sensor is set at control volume 7, the temperature collected by the temperature sensor can be used as the temperature of control volume 7 after the target calculation period ends.

[0061] After obtaining the temperatures of multiple control volumes after the target calculation period ends through step S220 or the temperature sensor, the temperature information of the battery cell after the target calculation period ends can be determined according to the temperatures of multiple control volumes after the target calculation period ends.

[0062] Among them, the temperature information includes the maximum temperature and / or the minimum temperature.

[0063] It should be noted that the highest temperature can be the temperature of the control volume with the highest temperature among them, and the lowest temperature can be the temperature of the control volume with the lowest temperature among them.

[0064] In the method for calculating the temperature of the battery cell provided in the embodiment of the present application, for a target control volume among multiple control volumes, the initial temperature of the target control volume can be obtained; according to the initial temperature of the target control volume and the heat information within the target calculation period, the temperature of the target control volume at the end of the target calculation period can be determined; furthermore, according to the temperatures of the multiple control volumes at the end of the target calculation period, the temperature information of the battery cell at the end of the target calculation period can be determined. Among them, by dividing the battery cell into multiple target control volumes, the temperature of each region in the battery cell can be determined more accurately, and then the temperature of the battery cell can be calculated based on the temperature of each target control volume, which can improve the accuracy of calculating the temperature of the battery cell.

[0065] To more clearly explain the calculation process of the temperature of the battery cell of the target control volume provided in the embodiment of the present application, the following will be explained by taking one control volume as an example.

[0066] Figure 3 For the structural schematic diagram of each control volume in the battery cell provided in the embodiment of the present application, please refer to Figure 3 , Figure 3 The control volume shown can be Figure 1 any one of the control volumes shown in

[0067] It should be noted that the target control volume can be a regular three-dimensional shape. For example: it can be in the shape of a quadrangular prism or a cylinder. Taking the battery cell shown in Figure 1 as an example, control volumes 1 - 8 can all be in the shape of a quadrangular prism; control volumes 9 - 10 can be in the shape of a quadrangular prism or a cylinder, and no specific limitation is made here.

[0068] For a control volume in the shape of a quadrangular prism, it can have six faces, and each face can correspond to a target object. Please refer to Figure 3 , the left and right two faces can be recorded as the faces in the x-axis direction, the left face can be used as the x1 face, and the right face can be used as the x2 face; the front and back two faces can be recorded as the faces in the y-axis direction, the front face can be used as the y1 face, and the back face can be used as the y2 face; the upper and lower two faces can be recorded as the faces in the z-axis direction, the upper face can be used as the z1 face, and the lower face can be used as the z2 face.

[0069] It should be noted that Figure 3Taking a quadrangular prism as an example for explanation, in the actual implementation process, the control volumes 9 and 10 can also be in the shape of a cylinder. If it is in the shape of a cylinder, the two faces in the z-axis direction can remain unchanged, and the four faces in the x and y-axis directions will be combined into one face, and the common contact object of this face is the external environment.

[0070] Next, based on the structure of the above control volume, another feasible implementation manner of the battery cell temperature calculation method provided in the embodiments of the present application will be explained.

[0071] Figure 4 Another flow diagram of the battery cell temperature calculation method provided in the embodiments of the present application is shown. Please refer to Figure 4 , before determining the temperature of the target control volume at the end of the target calculation period according to the initial temperature of the target control volume and the heat information within the target calculation period, the method further includes:

[0072] S410: Determine the heat exchanged between the target control volume and the target object within the target calculation period according to the product of the preset coefficient of each face of the target control volume and the temperature change difference.

[0073] Taking Figure 1 the control volume 3 in Figure 3 as an example, the control volume 3 can be in the shape of a quadrangular prism. Please refer to the control volume structure shown in

[0074] The control volume 3 can have six faces, and each face has a corresponding preset coefficient and temperature change difference. Among them, the preset coefficient is determined by the thermal conductivity of the face where the target object is located, the contact area with the target object, and the contact surface thickness of the target control volume, and the temperature change difference is determined by the difference between the initial temperature of the target control volume and the object temperature of the target object.

[0075] For the heat exchanged on any one face, the calculation formula is as follows:

[0076]

[0077] Among them, △Q can be the heat exchanged between a certain face of the target control volume and the target object, is the preset coefficient, where k is the thermal conductivity of the face where the target object is located, A is the contact area with the target object, D is the contact surface thickness of the target control volume, and (T0 - T) is the temperature change difference, where T0 is the initial temperature of the target control volume and T is the object temperature of the target object.

[0078] Taking the control volume 3 as an example, for the overall heat exchanged of the control volume 3, the calculation formula is as follows:

[0079]

[0080] Among them, △Q3 can be the heat exchanged between all the surfaces of the control volume 3 and all the target objects, k x , k y , k z are the thermal conductivities respectively indicating two surfaces on the x-axis, two surfaces on the y-axis, and two surfaces on the z-axis, A x1 , A x2 , A y1 , A y2 , A z1 , A z2 respectively indicate the contact areas between the x1 surface, x2 surface, y1 surface, y2 surface, z1 surface, and z2 surface and the target objects on the corresponding surfaces, D x1 , D x2 , D y1 , D y2 , D z1 , D z2 respectively indicate the contact surface thicknesses of the x1 surface, x2 surface, y1 surface, y2 surface, z1 surface, and z2 surface, refers to the initial temperature of the control volume 3, respectively indicate the object temperatures of the corresponding target objects on the x1 surface, x2 surface, y1 surface, y2 surface, z1 surface, and z2 surface.

[0081] Through the above formula, the heat exchanged by each target control volume can be calculated respectively.

[0082] It should be noted that the thermal conductivity of the surface where the target object is located can be a preset value, and the magnitude of this value depends on the material used for this surface; the contact area with the target object and the contact surface thickness of the target control volume can be fixed values obtained by pre-measurement. For example: during the process of dividing each control volume, the corresponding contact area and the thickness of each contact surface can be obtained.

[0083] Among them, each control volume can include length, width, and height. For the contact surface composed of length and width, the contact area of this contact surface is the product of length and width, and the thickness of this contact surface is the height; for the contact surface composed of length and height, the contact area of this contact surface is the product of length and height, and the thickness of this contact surface is the width; for the contact surface composed of height and width, the contact area of this contact surface is the product of height and width, and the thickness of this contact surface is the length.

[0084] In the method for calculating the cell temperature provided by the embodiments of the present application, the heat exchanged between the target control volume and the target object within the target calculation period can be determined according to the product of the preset coefficient of each surface of the target control volume and the temperature change difference. Among them, through the preset coefficient and the temperature change difference, the heat exchanged between each surface of the target control volume and the target object on the corresponding surface can be calculated more accurately, so that the heat exchanged between the target control volume as a whole and multiple target objects can be accurately obtained.

[0085] It should be noted that among the above-mentioned multiple parameters, the object temperature of the target object can be obtained through prediction or calculation. For different target objects, the determination method of the object temperature is different. The determination processes of the object temperature of different target objects will be explained separately below.

[0086] In one embodiment, when the target object is an adjacent control volume, the object temperature of the target object is determined by the average value of the initial temperature of the target control volume and the initial temperature of the adjacent control volume.

[0087] Continuing to take control volume 3 as an example, the upper surface of control volume 3 is adjacent to control volume 1, and the right surface of control volume 3 is adjacent to control volume 4.

[0088] For control volume 3, the upper surface corresponds to the z1 surface, and the right surface corresponds to the y2 surface. Then the calculation formulas for the object temperature of the target object on these two surfaces are as follows:

[0089]

[0090] Among them, can be the initial temperature of control volume 1, can be the initial temperature of control volume 4.

[0091] In one embodiment, when the target object is the external environment where the battery cell is located, the object temperature of the target object is determined by the control volume weight, the initial temperature of the target control volume, the environment weight, and the external environment temperature. Among them, the control volume weight is determined by the thermal conductivity of the surface where the external environment is located and the contact surface thickness of the target control volume, and the environment weight is determined by the convective heat transfer coefficient of the surface where the external environment is located.

[0092] Continuing to take control volume 3 as an example, the left, front, and rear surfaces of control volume 3 are all adjacent to the external environment.

[0093] For control volume 3, the left surface corresponds to the y1 surface, the front surface corresponds to the x1 surface, and the rear surface corresponds to the x2 surface. Then the calculation formulas for the object temperature of the target object on these three surfaces are as follows:

[0094]

[0095] Among them, h x is the convective heat transfer coefficient of the two surfaces on the x-axis, h y is the convective heat transfer coefficient of the two surfaces on the y-axis, T amb is the external environment temperature. Among them, can be the control volume weight, can be the environment weight.

[0096] In one embodiment, when the target object is a temperature control device:

[0097] If the time difference between the moment after the end of the target calculation period and the current moment is less than or equal to a preset threshold, the object temperature of the target object is obtained by a sensor in the temperature control device that detects the temperature of the temperature control medium.

[0098] It should be noted that if the time difference between the moment after the end of the target calculation period and the current moment is less than or equal to the preset threshold, it can be determined that the current temperature calculation is in the process of determining the real-time temperature, and the object temperature of the target object is measurable. The temperature obtained by the sensor in the temperature control device that detects the temperature of the temperature control medium can be used as the object temperature of the target object. Among them, the sensor in the temperature control device that detects the temperature of the temperature control medium can be set at the inlet and outlet of the coolant or heating liquid, and the inlet temperature or the outlet temperature can be used as the object temperature of the target object. In the actual implementation process, any one of these two temperatures can be used as the object temperature of the target object, and no specific limitation is made here.

[0099] Among them, if it is necessary to determine the highest temperature of the battery cell at the current moment, the higher one of the inlet temperature and the outlet temperature can be used as the object temperature of the target object; if it is necessary to determine the lowest temperature of the battery cell at the current moment, the lower one of the inlet temperature and the outlet temperature can be used as the object temperature of the target object.

[0100] If the time difference between the moment after the end of the target calculation period and the current moment is greater than the preset threshold, the object temperature of the target object is determined by the control volume weight, the initial temperature of the target control volume, the temperature control device weight, and the temperature of the temperature control medium in the temperature control device. Among them, the control volume weight is determined by the thermal conductivity of the surface where the temperature control device is located and the contact surface thickness of the target control volume, and the temperature control device weight is determined by the convective heat transfer coefficient of the surface where the temperature control device is located.

[0101] It should be noted that if the time difference between the moment after the end of the target calculation period and the current moment is greater than the preset threshold, it can be determined that the current temperature calculation is in the process of predicting the future temperature, and the object temperature of the target object is not measurable and can be obtained by calculation.

[0102] Continuing to take Control Volume 3 as an example, the bottom of Control Volume 3 is adjacent to the temperature control device.

[0103] For Control Volume 3, the bottom corresponds to the z2 surface, the front corresponds to the x1 surface, and the back corresponds to the x2 surface. Then the calculation formulas for the object temperatures of the target objects on these three surfaces are as follows:

[0104]

[0105] Among them, h z is the convective heat transfer coefficient of the two surfaces on the z-axis, T clntis the temperature of the temperature control medium in the temperature control device. For example, it can be the temperature of the coolant; It can be the control body weight, It can be the temperature control device weight.

[0106] It should be noted that when the temperature control device is in the three states of cooling on, heating on, or not on, the value of h z will be different.

[0107] In the method for calculating the cell temperature provided by the embodiments of the present application, different calculation methods can be used to determine the object temperature of the target object under different conditions of the target object, so that the temperature of the target object can be accurately calculated, and further the accuracy of the heat exchange between the target control body and the target object can be improved.

[0108] Next, another feasible implementation manner of the method for calculating the cell temperature provided by the embodiments of the present application will be explained.

[0109] Figure 5 For another flow diagram of the method for calculating the cell temperature provided by the embodiments of the present application, please refer to Figure 5 , before determining the temperature of the target control body at the end of the target calculation period according to the initial temperature of the target control body and the heat information within the target calculation period, the method further includes:

[0110] S510: Obtain the current and internal resistance of the target control body within the target calculation period.

[0111] It should be noted that the internal resistance of the target control body within the target calculation period can be obtained by looking up a table. For example, it can be obtained by querying the state of charge table (SOC, State Of Charge) of the battery temperature. Different methods can be used to obtain the current within the target calculation period.

[0112] In one embodiment, when the time difference between the end time of the target calculation period and the current time is greater than a preset threshold, the current and internal resistance within the target calculation period are obtained by querying the state of charge table of the battery temperature.

[0113] It should be noted that when the time difference between the end time of the target calculation period and the current time is greater than a preset threshold, it can be determined that the current temperature calculation is in the process of future temperature prediction, and the current cannot be directly obtained and can be obtained by looking up a table.

[0114] In one embodiment, when the time difference between the end time of the target calculation period and the current time is less than or equal to a preset threshold, the resistance within the target calculation period is obtained by querying the state of charge table of the battery temperature, and the current within the target calculation period is obtained by current sampling.

[0115] It should be noted that when the time difference between the moment after the end of the target calculation period and the current moment is less than or equal to a preset threshold, it can be determined that the current temperature calculation is in the process of determining the real-time temperature. The current can be directly obtained, and the current at the current moment can be obtained by means of current sampling, and the current at the current moment is used as the current within the target calculation period.

[0116] S520: Determine the self-generated heat of the target control volume within the target calculation period according to the current and internal resistance of the target control volume within the target calculation period.

[0117] It should be noted that after obtaining the current and internal resistance of the target control volume within the target calculation period, the self-generated heat of the target control volume within the target calculation period can be calculated. The specific calculation formula is as follows:

[0118]

[0119] Among them, Q is the heat generated by the target control volume within the target calculation period, I is the current of the target control volume within the target calculation period, and R is the internal resistance of the target control volume within the target calculation period.

[0120] In the cell temperature calculation method provided by the embodiments of the present application, the current and internal resistance of the target control volume within the target calculation period can be obtained; the self-generated heat of the target control volume within the target calculation period is determined according to the current and internal resistance of the target control volume within the target calculation period. Among them, through the current and internal resistance of the target control volume within the target calculation period, the self-generated heat of the target control volume within the target calculation period can be calculated more accurately.

[0121] The following explains the specific formula for calculating the temperature after the end of the target calculation period for the target control volume:

[0122]

[0123] Among them, △Q0 is the heat exchanged between the target control volume and each target object within the target calculation period, Q is the self-generated heat of the target control volume within the target calculation period, △t is the step size of the target calculation period, m is the mass of the target control volume, c is the specific heat capacity of the target control volume, is the initial temperature of the target control volume, is the temperature of the target control volume after the end of the target calculation period. The specific result of the temperature of the target control volume after the end of the target calculation period can be calculated through the above formula.

[0124] During the process of real-time temperature calculation and future temperature prediction, the meanings of the various parameters in the above formula will have more specific results. Now, the implementation process of real-time temperature calculation will be explained below.

[0125] In one embodiment, according to the initial temperature of the target control volume and the heat information within the target calculation period, the temperature of the target control volume at the end of the target calculation period is determined, including: when the time difference between the moment at the end of the target calculation period and the current moment is less than or equal to a preset threshold, the temperature of the target control volume at the current moment is determined based on the initial temperature of the target control volume in the target calculation period, the heat information at the current moment, the mass of the target control volume, and the specific heat capacity of the target control volume.

[0126] Among them, the product of the step size of the target calculation period and the number of iterations is less than or equal to a preset duration. The product of the heat information at the current moment and the step size of the target calculation period is equal to the product of the mass of the target control volume, the specific heat capacity of the target control volume, and the first interval temperature difference. The first interval temperature difference is the difference between the temperature of the target control volume at the current moment and the initial temperature in the target calculation period. The initial temperature of the target control volume in the target calculation period is equal to the temperature at the end of the previous target calculation period.

[0127] During the process of real-time temperature calculation, the step size △t of the target calculation period can take a value of 0.1 s, and the number of iterations can be 1 time.

[0128] It should be noted that the step size of the target calculation period refers to the corresponding time of the temperature obtained for each iterative calculation. For example: if the step size is 0.1 s, the temperature obtained for each iterative calculation is the temperature after 0.1 s. Since the operating cycle of the single-chip microcomputer of the battery management system is also 0.1 s, that is, the calculation of the temperature after 0.1 s is achieved within the operating time of 0.1 s, that is, the real-time calculation of the temperature is achieved.

[0129] Optionally, the preset duration can be, for example, 0.1 s. When the product of the step size of the target calculation period and the number of iterations is less than or equal to the preset duration, it can be determined that the real-time temperature calculation is being performed. The temperature obtained each time is the current temperature. That is to say, the temperature of the target control volume at the end of the target calculation period is the temperature of the target control volume at the current moment.

[0130] For the above formula for calculating the temperature at the end of the target calculation period, △Q0 is the heat exchanged between the target control volume and each target object at the current moment, Q is the self-generated heat of the target control volume at the current moment, △t is the step size of the target calculation period, which can be 0.1 s for example, m is the mass of the target control volume, c is the specific heat capacity of the target control volume, is the temperature at the end of the previous target calculation period, is the temperature at the current moment, which is the first interval temperature difference. Through the above formula, the temperature of the target control volume at the current moment can be calculated, thus realizing real-time temperature calculation.

[0131] In the method for calculating the temperature of the battery cell provided by the embodiments of the present application, when the time difference between the moment after the end of the target calculation period and the current moment is less than or equal to a preset threshold, the temperature of the target control volume at the current moment can be determined according to the initial temperature of the target control volume in the target calculation period, the heat information at the current moment, the mass of the target control volume, and the specific heat capacity of the target control volume. Among them, the temperature of the target control volume at the current moment can be accurately calculated through the initial temperature of the target control volume in the target calculation period, the heat information at the current moment, the mass of the target control volume, and the specific heat capacity of the target control volume.

[0132] In one embodiment, after determining the temperature information of the battery cell after the end of the target calculation period according to the temperatures of multiple control volumes after the end of the target calculation period, the method further includes: displaying the temperature of the battery cell at the current moment, where the temperature of the battery cell at the current moment includes: the temperature of the target control volume with the highest temperature at the current moment and / or the temperature of the target control volume with the lowest temperature at the current moment.

[0133] It should be noted that the real-time temperature is the temperature at the current moment. After obtaining the temperature of the target control volume at the current moment, the temperature of the battery cell at the current moment can be determined.

[0134] Optionally, the temperature of each target control volume at the current moment can be calculated in the above manner, where Figure 1 for the other control volumes except control volume 7, the temperature at the current moment can be calculated in the above manner. For control volume 7, since the temperature sensor is installed on control volume 7, the real-time detected temperature of the temperature sensor can be used as the temperature of control volume 7 at the current moment.

[0135] After obtaining the temperature of each control volume at the current moment, the temperature of the battery cell at the current moment can be obtained, and the temperature of the battery cell at the current moment can be displayed.

[0136] Figure 6 For the schematic diagram of the interface for displaying the current temperature of the battery cell provided in the embodiments of the present application, please refer to Figure 6 , in Figure 6 the highest temperature and the lowest temperature of the battery cell can be displayed, Figure 6 the displayed content in

[0137] Figure 6The content shown is the highest temperature and the lowest temperature in real time. During actual implementation, it is also possible to display one of the temperatures, or display the specific temperature of each control volume, which is not specifically limited here.

[0138] Exemplary: Figure 6 The highest temperature shown is 50 °C and the lowest temperature is 40 °C.

[0139] In the method for calculating the temperature of the battery cell provided by the embodiment of the present application, the temperature of the battery cell at the current moment can be displayed. The temperature of the battery cell at the current moment includes: the temperature of the target control volume with the highest temperature at the current moment and / or the temperature of the target control volume with the lowest temperature at the current moment. Among them, by displaying the temperature of the battery cell at the current moment, the user can timely understand the current temperature of the battery cell, so that the battery control can be more accurate.

[0140] The above process is the implementation process of real-time temperature calculation. During actual implementation, in addition to performing real-time temperature calculation, it is also possible to predict future temperatures.

[0141] In one embodiment, according to the initial temperature of the target control volume and the heat information within the target calculation period, determining the temperature of the target control volume after the end of the target calculation period includes: when the time difference between the moment after the end of the target calculation period and the current moment when the battery cell is in the charging state is less than or equal to the preset threshold, according to the initial temperature of the target control volume, the heat information of at least one prediction period, the mass of the target control volume, and the specific heat capacity of the target control volume, determining the temperature of the target control volume after at least one prediction period.

[0142] Among them, the target calculation period includes at least one prediction period. The product of the step size and the number of iterations within at least one prediction period is greater than the preset duration. The starting temperature of the target control volume in the first prediction period is equal to the initial temperature of the target control volume. The initial temperature of the target control volume is obtained by the temperature sensor of the battery cell when the battery cell is in the non-charging state. The starting temperature of the target control volume in other prediction periods except the first prediction period is equal to the end temperature of the previous prediction period. For any one prediction period, the product of the heat information of the prediction period and the step size of the prediction period is equal to the product of the mass of the target control volume, the specific heat capacity of the target control volume, and the second interval temperature difference. The second interval temperature difference is the difference between the end temperature and the starting temperature of the target control volume in the prediction period.

[0143] During the process of predicting future temperatures, the target calculation period can include multiple prediction periods. The step size △t within one prediction period can take a value of 2 s, and the number of iterations within one prediction period can be 24 times.

[0144] It should be noted that the step size of the prediction period refers to the corresponding time of the temperature obtained each time the iterative calculation is performed within the prediction period. For example, if the step size is 2s, then each time the iterative calculation is performed, the predicted temperature 2s later is obtained. If there can be 24 iterations within each prediction period, the temperature obtained after 24 iterations is the temperature 48s later. That is to say, a prediction period can obtain the temperature 48s later. Since the operating period of the single-chip microcomputer of the battery management system is 0.1s, the prediction period can be 0.1s. That is, the prediction of the temperature 48s later is realized within the operating time of 0.1s, that is, the prediction of the future temperature is realized.

[0145] Optionally, the preset duration can be, for example, 0.1s. When the product of the step size and the number of iterations of the prediction period is greater than the preset duration, it can be determined that the prediction of the future temperature is being performed, and the temperature obtained each time the calculation is performed is the prediction after a certain period of time. That is to say, the temperature of the target control body after at least one prediction period is the predicted temperature of the target control body after a certain period of time.

[0146] For the above formula for calculating the temperature after the end of the target calculation period, △Q0 is the heat exchange amount between the target control body and each target object within each prediction period, Q is the heat generated by the target control body itself within each prediction period, △t is the step size of each prediction period, which can be, for example, 2s, m is the mass of the target control body, and c is the specific heat capacity of the target control body. is the starting temperature of each prediction period, is the ending temperature of each prediction period, is the second interval temperature difference. Through the above formula, the temperature of the target control body after at least one prediction period can be calculated, thus realizing the prediction of the future temperature.

[0147] It should be noted that for If it is the first prediction period, then is obtained by the temperature sensor of the battery cell when the battery cell is not charging; if it is the second prediction period and subsequent prediction periods, then is the ending temperature of the previous prediction period, that is

[0148] During the process of temperature prediction, the time to be predicted is determined. For example: If the battery temperature 90 minutes later needs to be predicted, the corresponding number of prediction periods can be determined, and then the corresponding number of prediction periods can be executed to achieve the prediction.

[0149] Among them, according to the foregoing explanation, the battery temperature can be predicted 48 seconds later for each prediction cycle. If the battery temperature 90 minutes later is to be predicted, it can be determined that 123 prediction cycles need to be executed. Furthermore, the number of prediction cycles can be determined. Since the operation cycle of each prediction cycle is 0.1 s, 123 cycles need 11.3 seconds. That is to say, the single-chip microcomputer of the battery management system can predict the battery temperature 90 minutes later after running for 12.3 seconds.

[0150] In the core temperature calculation method provided by the embodiments of the present application, when the time difference between the moment after the target calculation cycle ends when the core is in the charging state and the current moment is less than or equal to a preset threshold, according to the initial temperature of the target control body, the heat information of at least one prediction cycle, the mass of the target control body, and the specific heat capacity of the target control body, the temperature of the target control body after at least one prediction cycle can be determined. Among them, through the initial temperature of the target control body, the heat information of at least one prediction cycle, the mass of the target control body, and the specific heat capacity of the target control body, the temperature of the target control body after at least one prediction cycle can be accurately calculated, so that temperature prediction can be more accurately realized.

[0151] In one embodiment, after determining the temperature information of the core after the target calculation cycle ends according to the temperatures of multiple control bodies after the target calculation cycle ends, the method further includes: displaying the temperature change curve of the core.

[0152] Among them, the temperature change curve is used to characterize the temperature change of at least one of the following target control bodies: the temperature change of the target control body with the highest temperature and the temperature change of the target control body with the lowest temperature when the temperature control device is not turned on; the temperature change of the target control body with the highest temperature when the temperature control device is turned on for cooling; the temperature change of the target control body with the lowest temperature when the temperature control device is turned on for heating.

[0153] It should be noted that the temperature displayed by the temperature change curve is the change of the predicted temperature in the future for a period of time. Each time an iteration is performed, or each time a prediction cycle is executed, one or more temperature values can be obtained, and these discrete temperature values can be fitted into the corresponding curve, so that the temperature change curve can be obtained.

[0154] Optionally, the temperature change curve of each target control body can be calculated in the above manner. After obtaining the temperature change curve of each target control body, the temperature change curve of the core can be obtained, and the temperature change curve of the core can be displayed.

[0155] Figure 7 For the schematic diagram of the interface for displaying the temperature change curve of the core provided in the embodiments of the present application, please refer toFigure 7 , in Figure 7 , multiple temperature change curves of the battery cells can be displayed. For example, it can include the temperature change conditions of the target control body with the highest temperature and the temperature change conditions of the target control body with the lowest temperature when the temperature control device is not turned on; the temperature change conditions of the target control body with the highest temperature when the temperature control device is turned on for cooling; the temperature change conditions of the target control body with the lowest temperature when the temperature control device is turned on for heating.

[0156] Figure 7 The content shown in

[0157] is the above four temperature change curves. In the actual implementation process, some of the temperature change curves can also be displayed, or the temperature change curves of each control body can be displayed, which is not specifically limited here. Figure 7 The curve shown is that the time step Δt of the prediction period is taken as 2 s, and each prediction period is iterated 24 times. Then, each time the single-chip microcomputer of the battery control system runs once, it can run for 0.1 s and can predict the temperature 48 s later. The next time it runs, it continues to calculate based on the prediction result of the previous run.

[0158] If the temperature within the next 90 min is predicted, the single-chip microcomputer needs to run 123 times in total, for a total of 12.3 s. When it runs to 12.4 s, the temperatures at each part of the battery cell are uniformly reset to the temperature at the current moment (the temperature at the current moment can be obtained by the aforementioned method of calculating the real-time temperature), and then the next round of operation can be carried out.

[0159] In the actual implementation process, the relevant parameters of the calculation can be calibrated. Different iteration times, time step lengths, and grid densities of the displayed images can be set according to the computing power of the in-vehicle BMS chip to find a balance between the operation speed and accuracy.

[0160] Figure 7 Among the multiple curves shown, the highest curve (curve 3) can be the temperature change curve of the target control body with the lowest temperature when the temperature control device is turned on for heating; the second-highest curve (curve 1) can be the temperature change curve of the target control body with the highest temperature when the temperature control device is not turned on; the second-next highest curve (curve 2) can be the temperature change curve of the target control body with the lowest temperature when the temperature control device is not turned on, and the lowest curve (curve 4) can be the temperature change curve of the target control body with the highest temperature when the temperature control device is turned on for cooling.

[0161] According to Figure 7 , it can be obtained that the reset period is about 12 - 13 s. Among them, the temperature 90 minutes later can be predicted at 12.3 s.

[0162] The above is shown in the following chartFigure 7 Data information of the corresponding four curves:

[0163]

[0164]

[0165] Table 1

[0166] The content shown in Table 1 is Figure 7 The temperature change of the four curves within a target calculation period (12.3 s) in [reference]. Taking the first set of data in the table as an example, at the initial time, for the predicted time being the current moment, for Curve 1, the SOC is 5% and the temperature is 23°C; for Curve 2, the SOC is 5% and the temperature is 21°C; for Curve 3, the SOC is 5% and the temperature is 23°C; for Curve 4, the SOC is 5% and the temperature is 23°C.

[0167] Through the calculation of multiple prediction periods, each prediction period can be iterated 24 times, and the numbers at each stage in Table 1 above can be obtained. Among them, after 12.4 s, the temperatures at each part of the battery cell are uniformly reset to the temperature at the current moment (the temperature at the current moment can be obtained by the aforementioned method of calculating the real-time temperature), and then the next round of operation can be carried out.

[0168] In the battery cell temperature calculation method provided by the embodiments of the present application, the temperature change curve of the battery cell can be displayed. Among them, by displaying the temperature change curves of the battery cell under different conditions, users can timely understand the temperature change of the battery cell in the future period of time, so as to more accurately control the battery.

[0169] It should be understood that although the steps in the above flowcharts are sequentially shown according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, at least a part of the steps in the above flowcharts may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same moment, but can be executed at different moments. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least a part of other steps or sub-steps or stages of other steps.

[0170] Based on the foregoing embodiments, an embodiment of the present application provides a core temperature calculation device. The device includes each module included therein, as well as each unit included in each module, and can be implemented by a processor; of course, it can also be implemented by specific logic circuits; during implementation, the processor can be a central processing unit (CPU), a microprocessor (MPU), a digital signal processor (DSP), or a field programmable gate array (FPGA), etc.

[0171] Figure 8 The following is a schematic structural diagram of the core temperature calculation device provided in the embodiment of the present application. Please refer to Figure 8 The device includes: an acquisition module 810, a calculation module 820, and a result module 830;

[0172] The acquisition module 810 is configured to acquire the initial temperature of a target control volume among a plurality of control volumes; the target control volume is any one of the plurality of control volumes;

[0173] The calculation module 820 is configured to determine the temperature of the target control volume at the end of the target calculation period according to the initial temperature of the target control volume and the heat information within the target calculation period. The heat information within the target calculation period includes: the heat exchanged between the target control volume and the target object within the target calculation period and its own heat generation. The target object includes at least one of the external environment where the core is located, an adjacent control volume, and a temperature control device;

[0174] The result module 830 is configured to determine the temperature information of the core at the end of the target calculation period according to the temperatures of the plurality of control volumes at the end of the target calculation period. The temperature information includes the maximum temperature and / or the minimum temperature.

[0175] In one embodiment, the calculation module 820 is further configured to determine the heat exchanged between the target control volume and the target object within the target calculation period according to the product of the preset coefficient of each surface of the target control volume and the temperature change difference. Wherein, the preset coefficient is determined by the thermal conductivity of the surface where the target object is located, the contact area with the target object, and the thickness of the contact surface of the target control volume. The temperature change difference is determined by the difference between the initial temperature of the target control volume and the object temperature of the target object.

[0176] In one embodiment, in the case where the target object is the adjacent control volume, the object temperature of the target object is determined by the average value of the initial temperature of the target control volume and the initial temperature of the adjacent control volume.

[0177] In one embodiment, in the device, when the target object is the external environment where the battery cell is located, the object temperature of the target object is determined by the control volume weight, the initial temperature of the target control volume, the environment weight, and the external environment temperature. Among them, the control volume weight is determined by the thermal conductivity of the surface where the external environment is located and the contact surface thickness of the target control volume, and the environment weight is determined by the convective heat transfer coefficient of the surface where the external environment is located.

[0178] In one embodiment, in the device, when the target object is the temperature control device:

[0179] If the time difference between the moment after the end of the target calculation period and the current moment is less than or equal to a preset threshold, the object temperature of the target object is obtained by a sensor for detecting the temperature of the temperature control medium in the temperature control device;

[0180] If the time difference between the moment after the end of the target calculation period and the current moment is greater than the preset threshold, the object temperature of the target object is determined by the control volume weight, the initial temperature of the target control volume, the temperature control device weight, and the temperature of the temperature control medium in the temperature control device. Among them, the control volume weight is determined by the thermal conductivity of the surface where the temperature control device is located and the contact surface thickness of the target control volume, and the temperature control device weight is determined by the convective heat transfer coefficient of the surface where the temperature control device is located.

[0181] In one embodiment, the calculation module 820 is further configured to obtain the current and internal resistance of the target control volume during the target calculation period. Among them, when the time difference between the moment after the end of the target calculation period and the current moment is greater than the preset threshold, the current and internal resistance during the target calculation period are obtained by querying the remaining power status table of the battery temperature; when the time difference between the moment after the end of the target calculation period and the current moment is less than or equal to the preset threshold, the resistance during the target calculation period is obtained by querying the remaining power status table of the battery temperature, and the current during the target calculation period is obtained by current sampling;

[0182] The self-heat generation amount of the target control volume during the target calculation period is determined according to the current and internal resistance of the target control volume during the target calculation period.

[0183] In one embodiment, the calculation module 820 is specifically configured to, when the time difference between the moment after the end of the target calculation period and the current moment is less than or equal to a preset threshold, determine the temperature of the target control body at the current moment according to the initial temperature of the target control body in the target calculation period, the heat information at the current moment, the mass of the target control body, and the specific heat capacity of the target control body, where the product of the step size of the target calculation period and the number of iterations is less than or equal to a preset duration, the product of the heat information at the current moment and the step size of the target calculation period is equal to the product of the mass of the target control body, the specific heat capacity of the target control body, and the first interval temperature difference, the first interval temperature difference is the difference between the temperature of the target control body at the current moment and the initial temperature in the target calculation period, and the initial temperature of the target control body in the target calculation period is equal to the temperature after the end of the previous target calculation period.

[0184] In one embodiment, the result module 830 is further configured to display the temperature of the battery cell at the current moment, where the temperature of the battery cell at the current moment includes: the temperature of the target control body with the highest temperature and / or the temperature of the target control body with the lowest temperature at the current moment.

[0185] In one embodiment, the calculation module 820 is specifically configured to, when the battery cell is in a charging state and the time difference between the moment after the end of the target calculation period and the current moment is less than or equal to a preset threshold, determine the temperature of the target control body after at least one prediction period according to the initial temperature of the target control body, the heat information of at least one prediction period, the mass of the target control body, and the specific heat capacity of the target control body, where the target calculation period includes at least one prediction period, the product of the step size of the at least one prediction period and the number of iterations is greater than a preset duration, the starting temperature of the target control body in the first prediction period is equal to the initial temperature of the target control body, and the initial temperature of the target control body is obtained by the temperature sensor of the battery cell when the battery cell is not charged; the starting temperature of the target control body in other prediction periods except the first prediction period is equal to the end temperature of the previous prediction period, and for any prediction period, the product of the heat information of the prediction period and the step size of the prediction period is equal to the product of the mass of the target control body, the specific heat capacity of the target control body, and the second interval temperature difference, and the second interval temperature difference is the difference between the end temperature and the starting temperature of the target control body in the prediction period.

[0186] In one embodiment, the result module 830 is further configured to display a temperature change curve of the battery cell, where the temperature change curve is used to characterize the temperature change of at least one of the following target control volumes: the temperature change of the target control volume with the highest temperature and the temperature change of the target control volume with the lowest temperature when the temperature control device is not turned on; the temperature change of the target control volume with the highest temperature when the temperature control device is turned on for cooling; the temperature change of the target control volume with the lowest temperature when the temperature control device is turned on for heating.

[0187] In the battery cell temperature calculation device provided by the embodiments of the present application, for the target control volume among multiple control volumes, the initial temperature of the target control volume can be obtained; according to the initial temperature of the target control volume and the heat information within the target calculation period, the temperature of the target control volume at the end of the target calculation period can be determined; furthermore, according to the temperatures of multiple control volumes at the end of the target calculation period, the temperature information of the battery cell at the end of the target calculation period can be determined. Among them, by dividing the battery cell into multiple target control volumes, the temperature of each area in the battery cell can be determined more accurately. Furthermore, the temperature of the battery cell can be calculated based on the temperature of each target control volume, which can improve the accuracy of battery cell temperature calculation.

[0188] The description of the above device embodiments is similar to the description of the above method embodiments and has similar beneficial effects to the method embodiments. For the technical details not disclosed in the device embodiments of the present application, please refer to the description of the method embodiments of the present application for understanding.

[0189] It should be noted that in the embodiments of the present application Figure 8 The division of the battery cell temperature calculation device shown into modules is illustrative, merely a logical function division, and there may be other division methods in actual implementation. In addition, each functional unit in the various embodiments of the present application may be integrated in one processing unit, may exist independently physically, or two or more units may be integrated in one unit. The above integrated units may be implemented in the form of hardware, or in the form of software functional units, or in the form of a combination of software and hardware.

[0190] It should be noted that in the embodiments of the present application, if the above-mentioned method is implemented in the form of software function modules and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the embodiments of the present application, in essence or the part that contributes to the related technology, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing an electronic device to execute all or part of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), magnetic disks, or optical discs that can store program codes. In this way, the embodiments of the present application are not limited to any specific combination of hardware and software.

[0191] Figure 9 The following is a schematic structural diagram of the computer device provided in the embodiments of the present application. Please refer to Figure 9 In the embodiments of the present application, a computer device is provided. This computer device can be the controller of the above-mentioned BMS, and its internal structure diagram can be as Figure 9 shown. The computer device includes a processor 920, a memory, and a network interface 940 connected through a system bus 910. Among them, the processor 920 of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium 931 and an internal memory 932. The non-volatile storage medium 931 stores an operating system, computer programs, and a database. The internal memory 932 provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium 931. The database of the computer device is used to store data. The network interface 940 of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor 920, the above-mentioned method is implemented.

[0192] The embodiments of the present application provide a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps in the method provided in the above embodiments are implemented.

[0193] The embodiments of the present application provide a computer program product containing instructions. When it runs on a computer, it causes the computer to execute the steps in the method provided in the above method embodiments.

[0194] Those skilled in the art can understand that Figure 9 the structure shown in

[0195] In one embodiment, the cell temperature calculation device provided by the present application can be implemented in the form of a computer program, and the computer program can run on a computer device as shown in Figure 9 . Each program module that makes up the above device can be stored in the memory of the computer device. The computer program composed of each program module enables the processor to execute the steps in the methods of various embodiments of the present application described in this specification.

[0196] It should be noted here that the descriptions of the above storage medium and device embodiments are similar to those of the above method embodiments and have similar beneficial effects to the method embodiments. For the technical details not disclosed in the storage medium, storage medium and device embodiments of the present application, please refer to the descriptions of the method embodiments of the present application for understanding.

[0197] It should be understood that the phrase "in one embodiment" or "in an embodiment" or "in some embodiments" mentioned throughout the specification means that specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, the phrases "in one embodiment", "in an embodiment" or "in some embodiments" that appear throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in various embodiments of the present application, the magnitudes of the sequence numbers of the above processes do not mean the order of execution, and the order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application. The sequence numbers of the embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments. The above descriptions of the various embodiments tend to emphasize the differences between the various embodiments, and the same or similar parts can be referred to each other. For the sake of brevity, they will not be repeated herein.

[0198] The term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, object A and / or object B can represent three situations: object A exists alone, object A and object B exist simultaneously, and object B exists alone.

[0199] It should be noted that in this article, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such a process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including that element.

[0200] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The embodiments described above are merely illustrative. For example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation. For example, multiple modules or components can be combined, or can be integrated into another system, or some features can be ignored, or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed with each other can be through some interfaces, and the indirect coupling or communication connection of devices or modules can be electrical, mechanical, or other forms.

[0201] The modules described above as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules; they can be located in one place or distributed to multiple network units; some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0202] In addition, each functional module in the embodiments of the present application can be all integrated in a processing unit, or each module can be separately used as a unit, or two or more modules can be integrated in a unit; the above-mentioned integrated modules can be implemented in the form of hardware, or in the form of a combination of hardware and software functional units.

[0203] Those of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions. The foregoing program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps including the above method embodiments; and the foregoing storage medium includes: removable storage devices, read-only memory (ROM), magnetic disks, or optical disks, etc., which can store program codes.

[0204] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the embodiments of the present application essentially or the part that contributes to the related technology can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions to enable an electronic device to execute all or part of the methods described in the various embodiments of the present application. And the foregoing storage medium includes: removable storage devices, ROM, magnetic disks, or optical disks, etc., which can store program codes.

[0205] The methods disclosed in several method embodiments provided in the present application can be arbitrarily combined without conflict to obtain new method embodiments.

[0206] The features disclosed in several product embodiments provided by this application can be combined arbitrarily without conflict to obtain new product embodiments.

[0207] The features disclosed in several method or device embodiments provided by this application can be combined arbitrarily without conflict to obtain new method embodiments or device embodiments.

[0208] As mentioned above, it is only the implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of changes or substitutions, which should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. A method for calculating battery core temperature, characterized in that: A battery management system applied to a vehicle, the vehicle comprising a battery cell, the battery cell comprising a plurality of pre-divided control bodies, the method comprising: For a target control body among the multiple control bodies, acquiring an initial temperature of the target control body; the target control body is any one of the multiple control bodies; Determine the temperature of the target control body after the target calculation cycle ends according to the initial temperature of the target control body and the heat information in the target calculation cycle, wherein the heat information in the target calculation cycle includes: the heat exchanged between the target control body and the target object and the heat generated by the target control body itself in the target calculation cycle, wherein the target object includes at least one of the external environment where the battery cell is located, an adjacent control body, and a temperature regulating device; According to the temperatures of the multiple control bodies after the target calculation cycle ends, the temperature information of the battery cell after the target calculation cycle ends is determined, and the temperature information includes the highest temperature and / or the lowest temperature.

2. The method according to claim 1, characterized in that: Before determining the temperature of the target control body after the target calculation cycle ends based on the initial temperature of the target control body and the heat information in the target calculation cycle, the method further includes: The heat exchanged between the target control body and the target object during the target calculation period is determined based on the product of a preset coefficient and a temperature change difference on each surface of the target control body, wherein the preset coefficient is determined by the thermal conductivity of the surface where the target object is located, the contact area with the target object, and the contact surface thickness of the target control body, and the temperature change difference is determined by the difference between the initial temperature of the target control body and the object temperature of the target object.

3. The method according to claim 2, characterized in that In the case that the target object is the adjacent control body, the object temperature of the target object is determined by the average of the initial temperature of the target control body and the initial temperature of the adjacent control body.

4. The method according to claim 2, characterized in that: In the case where the target object is the external environment where the battery cell is located, the object temperature of the target object is determined by the control body weight, the initial temperature of the target control body, the environmental weight and the external environment temperature, wherein the control body weight is determined by the thermal conductivity of the surface where the external environment is located and the contact surface thickness of the target control body, and the environmental weight is determined by the convection heat transfer coefficient of the surface where the external environment is located.

5. The method according to claim 2, characterized in that: When the target object is the temperature control device: If the time difference between the moment when the target calculation cycle ends and the current moment is less than or equal to a preset threshold, the object temperature of the target object is obtained by a sensor in the temperature control device that detects the temperature of the temperature control medium; If the time difference between the moment after the end of the target calculation cycle and the current moment is greater than the preset threshold, the object temperature of the target object is determined by the control body weight, the initial temperature of the target control body, the temperature control device weight and the temperature of the temperature control medium in the temperature control device, wherein the control body weight is determined by the thermal conductivity of the surface where the temperature control device is located and the contact surface thickness of the target control body, and the temperature control device weight is determined by the convection heat transfer coefficient of the surface where the temperature control device is located.

6. The method according to claim 1, characterized in that Before determining the temperature of the target control body after the target calculation cycle ends based on the initial temperature of the target control body and the heat information in the target calculation cycle, the method further includes: Obtaining the current and internal resistance of the target control body within the target calculation cycle, wherein, when the time difference between the moment after the end of the target calculation cycle and the current moment is greater than a preset threshold, the current and internal resistance within the target calculation cycle are obtained by querying the remaining power state table of the battery temperature; when the time difference between the moment after the end of the target calculation cycle and the current moment is less than or equal to the preset threshold, the resistance within the target calculation cycle is obtained by querying the remaining power state table of the battery temperature, and the current within the target calculation cycle is obtained by current sampling; The self-heat generation of the target control body in the target calculation period is determined according to the current and internal resistance of the target control body in the target calculation period.

7. The method according to claim 1, characterized in that The step of determining the temperature of the target control body after the target calculation period ends according to the initial temperature of the target control body and the heat information in the target calculation period includes: When the time difference between the moment after the end of the target calculation cycle and the current moment is less than or equal to a preset threshold, the temperature of the target control body at the current moment is determined according to the initial temperature of the target control body in the target calculation cycle, the heat information at the current moment, the mass of the target control body and the specific heat capacity of the target control body, wherein the product of the step length of the target calculation cycle and the number of iterations is less than or equal to the preset duration, the product of the heat information at the current moment and the step length of the target calculation cycle is equal to the product of the mass of the target control body, the specific heat capacity of the target control body and the first interval temperature difference, the first interval temperature difference is the difference between the temperature of the target control body at the current moment and the initial temperature in the target calculation cycle, and the initial temperature of the target control body in the target calculation cycle is equal to the temperature after the end of the previous target calculation cycle.

8. The method according to claim 7, characterized in that After determining the temperature information of the battery cell after the target calculation cycle ends according to the temperatures of the multiple control bodies after the target calculation cycle ends, the method further includes: The temperature of the battery cell at the current moment is displayed, where the temperature of the battery cell at the current moment includes: the temperature of the target control body with the highest temperature at the current moment and / or the temperature of the target control body with the lowest temperature at the current moment.

9. The method according to claim 1, characterized in that: The step of determining the temperature of the target control body after the target calculation period ends according to the initial temperature of the target control body and the heat information in the target calculation period includes: When the battery cell is in a charging state and the time difference between the moment after the end of the target calculation cycle and the current moment is less than or equal to a preset threshold, the temperature of the target control body after at least one prediction cycle is determined according to the initial temperature of the target control body, the heat information of at least one prediction cycle, the mass of the target control body and the specific heat capacity of the target control body, wherein the target calculation cycle includes at least one prediction cycle, the product of the step length of the at least one prediction cycle and the number of iterations is greater than the preset time length, the starting temperature of the target control body in the first prediction cycle is equal to the initial temperature of the target control body, and the initial temperature of the target control body is obtained by the temperature sensor of the battery cell when the battery cell is not charged; the starting temperature of the target control body in other prediction cycles except the first prediction cycle is equal to the ending temperature of the previous prediction cycle, and for any prediction cycle, the product of the heat information of the prediction cycle and the step length of the prediction cycle is equal to the product of the mass of the target control body, the specific heat capacity of the target control body and the second interval temperature difference, and the second interval temperature difference is the difference between the ending temperature and the starting temperature of the target control body in the prediction cycle.

10. The method according to claim 9, characterized in that After determining the temperature information of the battery cell after the target calculation cycle ends according to the temperatures of the multiple control bodies after the target calculation cycle ends, the method further includes: The temperature change curve of the battery cell is displayed, and the temperature change curve is used to characterize the temperature change of at least one of the following target control bodies: when the temperature control device is not turned on, the temperature change of the target control body with the highest temperature and the temperature change of the target control body with the lowest temperature; when the temperature control device is turned on for cooling, the temperature change of the target control body with the highest temperature; when the temperature control device is turned on for heating, the temperature change of the target control body with the lowest temperature.

11. A battery core temperature calculation device, characterized in that: A battery management system applied to a vehicle, the vehicle comprising a battery cell, the battery cell comprising a plurality of pre-divided control bodies, the device comprising: an acquisition module, a calculation module, and a result module; The acquisition module is used to acquire the initial temperature of a target control body among the multiple control bodies; the target control body is any one of the multiple control bodies; The calculation module is used to determine the temperature of the target control body after the target calculation cycle ends according to the initial temperature of the target control body and the heat information in the target calculation cycle, wherein the heat information in the target calculation cycle includes: the heat exchanged between the target control body and the target object and the heat generated by the target control body itself in the target calculation cycle, wherein the target object includes at least one of the external environment where the battery cell is located, an adjacent control body and a temperature control device; The result module is used to determine the temperature information of the battery cell after the target calculation cycle ends according to the temperatures of the multiple control bodies after the target calculation cycle ends, and the temperature information includes the highest temperature and / or the lowest temperature.

12. A computer device comprising a memory and a processor, wherein the memory stores a computer program executable on the processor, wherein: When the processor executes the program, the steps of the method according to any one of claims 1 to 10 are implemented.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 10 is implemented.

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