Battery testing method, testing device, computing equipment, medium and program product

Abstract

The invention provides a battery testing method and device, computing equipment, a medium and a program product, and belongs to the technical field of batteries. The method comprises the following steps: acquiring the maximum value of the temperature difference between every two sub-regions on the surface of a single battery as a first temperature difference, wherein the sub-regions are different regions on the surface of the single battery; a second temperature difference between the actual temperature of the circulating liquid and the set temperature is obtained, and the single battery is placed in the circulating liquid to be tested; under the condition that any one of the first temperature difference and the second temperature difference is larger than a preset value, the temperature of the circulating liquid is adjusted, and / or the flow of the circulating liquid is adjusted; wherein all the steps are recorded as one-time temperature adjustment, and N times of temperature adjustment are executed, so that the temperature difference between every two sub-regions and the temperature difference between the actual temperature of the circulating liquid and the set temperature are both smaller than preset values, and N is an integer larger than or equal to 1. The method provided by the invention can improve the effectiveness of the battery test result.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery testing method, testing device, computing equipment, medium and program product. Background Art

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development.

[0003] The internal resistance of a battery is an important parameter that reflects the battery's performance, and temperature has a significant impact on the battery's internal resistance. Based on this, the battery needs to be placed in a set temperature environment and tested to evaluate its performance.

[0004] However, during the current battery testing process, the test temperature of the battery is not well controlled, resulting in the effectiveness of the battery test results needing to be further improved. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems in the background technology. To this end, one object of the present application is to provide a battery testing method, testing device, computing equipment, medium and program product to improve the validity of battery test results.

[0006] An embodiment of the first aspect of the present application provides a battery testing method, the method comprising: obtaining the maximum value of the temperature difference between each sub-region on the surface of the battery cell as a first temperature difference, each sub-region being a different region on the surface of the battery cell; obtaining a second temperature difference between the actual temperature of the circulating fluid and a set temperature, wherein the battery cell is placed in the circulating fluid for testing; when either the first temperature difference or the second temperature difference is greater than a preset value, adjusting the temperature of the circulating fluid and / or adjusting the flow rate of the circulating fluid; wherein all the above steps are recorded as one temperature adjustment, and N temperature adjustments are performed so that the temperature difference between each of the sub-regions and the temperature difference between the actual temperature of the circulating fluid and the set temperature are both less than the preset value, and N is an integer greater than or equal to 1.

[0007] In the technical solution of the embodiment of the present application, by performing N times of temperature adjustment, the first temperature difference and the second temperature difference can be continuously obtained, and when either of the first temperature difference and the second temperature difference is greater than a preset value, the temperature and / or flow rate of the circulating fluid is continuously adjusted so that the obtained first temperature difference and the second temperature difference are both less than the preset value. In this way, the maximum value of the temperature difference between each sub-area on the surface of the battery cell is less than the preset value, and while achieving the improvement of the uniformity of the surface temperature of the battery cell, the temperature of the circulating fluid can be controlled to approach or reach the set temperature, so that the temperature of the battery cell immersed in the circulating fluid is also close to or reaches the set temperature, thereby improving the validity of the test results.

[0008] In some embodiments, when either the first temperature difference or the second temperature difference is greater than a preset value, adjusting the temperature of the circulating fluid and / or the flow rate of the circulating fluid includes: when either the first temperature difference or the second temperature difference is greater than a preset value, using the larger of the first temperature difference or the second temperature difference as a temperature deviation value; and adjusting the temperature of the circulating fluid by a first feedback control algorithm and / or adjusting the flow rate of the circulating fluid by a second feedback control algorithm based on the temperature deviation value. Thus, according to the actual temperature deviation value, the feedback control algorithm is used to adjust the temperature and / or flow rate of the circulating fluid to reduce the first temperature difference and the second temperature difference, which can improve the control effect of the temperature.

[0009] In some embodiments, adjusting the temperature of the circulating fluid by the first feedback control algorithm based on the temperature deviation value includes: determining a target temperature of the circulating fluid based on the temperature deviation value; and adjusting the temperature of the circulating fluid by the first feedback control algorithm based on the target temperature and the actual temperature of the circulating fluid. Using the temperature deviation value as a basis for determining the target temperature of the circulating fluid can more specifically reduce the maximum temperature difference between the various sub-areas on the surface of the battery cell, as well as the temperature difference between the circulating fluid and the set temperature, thereby improving the temperature regulation efficiency.

[0010] In some embodiments, the first temperature difference is used as the temperature deviation value, and based on the temperature deviation value, determining the target temperature of the circulating fluid includes: obtaining the current temperature of the circulating fluid, the current temperature being the actual temperature of the circulating fluid at the time of obtaining the temperature deviation value; obtaining the target temperature based on the current temperature and the temperature deviation value; the second temperature difference is used as the temperature deviation value, and based on the temperature deviation value, determining the target temperature of the circulating fluid includes: using the set temperature as the target temperature. Thus, when the first temperature difference is used as the temperature deviation value, the current temperature of the circulating fluid can be adjusted based on the temperature deviation value, so as to effectively control the maximum temperature difference between each sub-area on the surface of the current battery cell, thereby improving the temperature uniformity of the battery cell surface. When the second temperature difference is used as the temperature deviation value, the set temperature is used as the target temperature to adjust the temperature of the circulating fluid to be close to or equal to the set temperature, so that the temperature of the battery cell immersed in the circulating fluid can also be close to or reach the set temperature, thereby improving the validity of the test results.

[0011] In some embodiments, obtaining the target temperature based on the current temperature and the temperature deviation value includes: taking the sum of the current temperature and the temperature deviation value as the target temperature. That is, the temperature of the circulating fluid is increased by the temperature deviation value to reach the target temperature. The reason for the temperature difference on the surface of the battery cell is usually that the self-heating of some parts of the battery cell is more serious, forming a higher temperature area, and the lower temperature area is immersed in the circulating fluid and is closer to the temperature of the circulating fluid. Therefore, in the process of heating the circulating fluid to the target temperature, the sub-area with the lowest temperature in each sub-area on the surface of the battery cell increases with the increase in the temperature of the circulating fluid, and the increased temperature is close to or equal to the temperature deviation value. Since the temperature of the sub-area with the highest temperature in each sub-area on the surface of the battery cell is usually greater than the temperature of the circulating fluid, in the process of heating the circulating fluid, no or less heat is transferred to the sub-area with the highest temperature, so that the temperature rise of the sub-area with the highest temperature is small, so that the maximum temperature difference between the sub-areas on the surface of the battery cell can be effectively reduced in a targeted manner.

[0012] In some embodiments, obtaining the target temperature based on the current temperature and the temperature deviation value includes: when the larger of the temperatures of the two sub-areas forming the first temperature difference is greater than the set temperature, taking the difference between the current temperature and the temperature deviation value as the target temperature; when the larger of the temperatures of the two sub-areas forming the first temperature difference is less than the set temperature, taking the sum of the current temperature and the temperature deviation value as the target temperature. Thus, after repeatedly performing temperature adjustment for multiple times, the first temperature difference can be adjusted to be less than the preset value, and during the adjustment process, the overall temperature of the battery cell can be controlled near the set temperature, which is conducive to achieving a better temperature control effect on the battery cell.

[0013] In some embodiments, based on the temperature deviation value, regulating the flow rate of the circulating fluid through the second feedback control algorithm includes: determining a first target flow rate of the circulating fluid based on the temperature deviation value; and regulating the temperature of the circulating fluid through the second feedback control algorithm based on the first target flow rate and the actual flow rate of the circulating fluid. The flow rate of the circulating fluid can affect the temperature of the circulating fluid. Therefore, the first target flow rate is determined based on the temperature difference deviation value, so that after the flow rate is adjusted to the first target flow rate, the first temperature difference or the second temperature difference can be reduced. In the embodiments of the present application, both the flow rate regulation of the circulating fluid and the temperature regulation of the circulating fluid can be used to diversify the regulation methods. In the event that any regulation method fails, other regulation methods can be used to improve the reliability of temperature control.

[0014] In some embodiments, based on the temperature deviation value, determining the first target flow rate of the circulating fluid includes: obtaining a first mapping relationship, the first mapping relationship is used to characterize the flow rate required to increase or decrease when the temperature of the circulating fluid changes by P degrees, where P is a real number; determining a first change value of the flow rate of the circulating fluid according to the temperature deviation value and the first mapping relationship; obtaining a first current flow rate of the circulating fluid, the first current flow rate being the actual flow rate of the circulating fluid at the moment of obtaining the temperature deviation value; and obtaining a first target flow rate based on the first current flow rate and the first change value. The first current flow rate of the circulating fluid is adjusted based on the first mapping relationship and the temperature deviation value, so that the current temperature of the circulating fluid can change the temperature deviation value to effectively reduce the first temperature difference or the second temperature difference.

[0015] In some embodiments, the first temperature difference is used as the temperature deviation value, and according to the temperature deviation value and the first mapping relationship, determining the first change value of the flow rate of the circulating fluid includes: according to the temperature deviation value and the first mapping relationship, determining the flow rate required to reduce the temperature of the circulating fluid by the temperature deviation value as the first change value; obtaining the first target flow rate based on the first current flow rate and the first change value includes: taking the sum of the first current flow rate and the first change value as the first target flow rate. That is, increasing the flow rate of the circulating fluid by the first change value to achieve the first target flow rate. In the process of increasing the flow rate of the circulating fluid to reduce the temperature of the circulating fluid, the temperature difference between the highest temperature sub-region of each sub-region on the surface of the battery cell and the circulating fluid is greater than the temperature difference between the lowest temperature sub-region and the circulating fluid, so that the heat exchange between the highest temperature sub-region and the circulating fluid is greater than the heat exchange between the lowest temperature sub-region and the circulating fluid, so that the temperature drop of the highest temperature sub-region is greater than the temperature drop of the lowest temperature sub-region, thereby reducing the first temperature difference. In addition, by increasing the flow rate of the circulating fluid, the heat exchange between the circulating fluid and the sub-region with the highest temperature among the sub-regions on the surface of the battery cell can be accelerated, so that the cooling effect of the sub-region with the highest temperature is more obvious, thereby further reducing the first temperature difference.

[0016] In some embodiments, the second temperature difference is used as the temperature deviation value, and the first change value of the flow rate of the circulating fluid is determined according to the temperature deviation value and the first mapping relationship, including: when the actual temperature of the circulating fluid is less than the set temperature, based on the temperature deviation value and the first mapping relationship, the first flow rate of the circulating fluid that increases and the temperature deviation value decreases is determined as the first change value; when the actual temperature of the circulating fluid is greater than the set temperature, based on the temperature deviation value and the first mapping relationship, the second flow rate of the circulating fluid that decreases and the temperature deviation value increases is determined as the first change value. In this way, the temperature of the circulating fluid can be accurately adjusted so that the temperature of the circulating fluid is close to or equal to the set temperature.

[0017] In some embodiments, based on the temperature deviation value, adjusting the temperature of the circulating fluid through the first feedback control algorithm, and adjusting the flow rate of the circulating fluid through the second feedback control algorithm include: determining the target temperature of the circulating fluid based on the temperature deviation value; obtaining the first output value of the first feedback control algorithm based on the deviation value between the target temperature of the circulating fluid and the actual temperature of the circulating fluid; adjusting the temperature of the circulating fluid based on the first output value; and determining the second target flow rate of the circulating fluid based on the first output value; and adjusting the flow rate of the circulating fluid through the second feedback control algorithm based on the second target flow rate and the actual flow rate of the circulating fluid. Thus, the temperature of the circulating fluid is used as the main control, and the temperature of the circulating fluid is regulated according to the first output value output by the first feedback control algorithm. At the same time, the second target flow rate of the circulating fluid is determined according to the first output value, and the flow rate of the circulating fluid is regulated by the second feedback control algorithm to assist in temperature control, thereby improving the efficiency of regulating the temperature of the circulating fluid based on the first output value.

[0018] In some embodiments, when the first mapping relationship is used to characterize the flow rate required to increase or decrease when the temperature of the circulating fluid changes by P degrees, determining the second target flow rate of the circulating fluid based on the first output value includes: determining the second change value of the flow rate of the circulating fluid according to the first output value and the first mapping relationship; obtaining the second current flow rate of the circulating fluid, the second current flow rate being the actual flow rate of the circulating fluid at the moment of obtaining the first output value; and obtaining the second target flow rate based on the second current flow rate and the second change value. The flow rate of the circulating fluid is adjusted based on the first mapping relationship and the first output value, so that the temperature of the circulating fluid can be adjusted simultaneously through temperature adjustment and flow adjustment to achieve the purpose of changing the first output value more quickly.

[0019] In some embodiments, adjusting the temperature of the circulating fluid through the first feedback control algorithm based on the temperature deviation value, and / or adjusting the flow rate of the circulating fluid through the second feedback control algorithm only includes one sub-stage, in which the temperature of the circulating fluid is adjusted through the first feedback control algorithm based on the temperature deviation value, and the flow rate of the circulating fluid is adjusted through the second feedback control algorithm; or, adjusting the temperature of the circulating fluid through the first feedback control algorithm based on the temperature deviation value; or, adjusting the flow rate of the circulating fluid through the second feedback control algorithm based on the temperature deviation value. That is, in the entire adjustment process, the same control method is used for regulation throughout the process, simplifying the control method.

[0020] In some embodiments, adjusting the temperature of the circulating fluid through the first feedback control algorithm based on the temperature deviation value, and / or adjusting the flow rate of the circulating fluid through the second feedback control algorithm includes two consecutive sub-stages, in which the temperature of the circulating fluid is adjusted through the first feedback control algorithm based on the temperature deviation value, or the flow rate of the circulating fluid is adjusted through the second feedback control algorithm based on the temperature deviation value; in the other sub-stage, adjusting the temperature of the circulating fluid through the first feedback control algorithm based on the temperature deviation value, and adjusting the flow rate of the circulating fluid through the second feedback control algorithm are performed. Thus, different control methods are used in different sub-stages, and control can be performed according to different temperature conditions to improve the reliability of temperature control.

[0021] In some embodiments, the method further includes: adjusting the calculation coefficient of the first feedback control algorithm in response to the output value of the first feedback control algorithm; and / or adjusting the calculation coefficient of the second feedback control algorithm in response to the output value of the second feedback control algorithm. Adjusting the calculation coefficients of the first feedback control algorithm and the second feedback control algorithm according to the output value can optimize the control performance and improve the accuracy of temperature control.

[0022] The second aspect of the present application provides a test device for battery testing, which includes a test chamber, a circulating fluid is introduced into the test chamber, and the test chamber is used to accommodate a battery cell; a first temperature acquisition module, which is used to acquire the temperature of each sub-region on the surface of the battery cell, each sub-region being a different region on the surface of the battery cell; a second temperature acquisition module, which is used to acquire a second temperature difference between the actual temperature of the circulating fluid and the set temperature; and an adjustment module, which is used to acquire the maximum value of the temperature difference between each sub-region as the first temperature difference based on the temperature of each sub-region, and adjust the temperature of the circulating fluid and / or the flow rate of the circulating fluid when either the first temperature difference or the second temperature difference is greater than a preset value. Thus, the temperature of the circulating fluid and / or the flow rate of the circulating fluid can be adjusted based on the first temperature difference or the second temperature difference by the adjustment module, so that the maximum value of the temperature difference between each sub-region on the surface of the battery cell is less than the preset value, and the temperature of the circulating fluid can be controlled to approach or reach the set temperature while achieving the improvement of the uniformity of the surface temperature of the battery cell, so that the temperature of the battery cell immersed in the circulating fluid also approaches or reaches the set temperature, thereby improving the validity of the test results.

[0023] In some embodiments, the regulating module includes: a first controller, which is used to use the larger of the first temperature difference and the second temperature difference as the temperature deviation value when either of the first temperature difference and the second temperature difference is greater than a preset value, and adjust the temperature of the circulating fluid through a first feedback control algorithm based on the temperature deviation value; a second controller, which is used to use the larger of the first temperature difference and the second temperature difference as the temperature deviation value when either of the first temperature difference and the second temperature difference is greater than a preset value, and adjust the flow rate of the circulating fluid through a second feedback control algorithm based on the temperature deviation value. Thus, according to the actual temperature deviation value, the feedback control algorithm is used to adjust the temperature and / or flow rate of the circulating fluid to reduce the first temperature difference and the second temperature difference, which can improve the control effect of the temperature.

[0024] In some embodiments, the temperature acquisition module includes: a plurality of temperature acquisition units, the plurality of temperature acquisition units are disposed in a one-to-one correspondence in a plurality of sub-regions, and are used to acquire the temperature of each sub-region, wherein each temperature acquisition unit is in communication connection with the adjustment module, so that the adjustment module receives the temperature value acquired by the temperature acquisition unit. The temperature of each sub-region can be accurately acquired through the plurality of temperature acquisition units, so as to improve the accuracy of temperature control.

[0025] An embodiment of the third aspect of the present application provides a computing device, which includes at least one processor; and at least one memory communicatively connected to the at least one processor, the at least one memory storing instructions, which, when executed individually or collectively by the at least one processor, enable the computing device to execute the method in the above embodiment.

[0026] An embodiment of the fourth aspect of the present application provides a computer-readable storage medium storing instructions, which, when executed individually or collectively by one or more processors of a computing device, cause the computing device to execute the method in the above embodiment.

[0027] An embodiment of the fifth aspect of the present application provides a computer program product, which includes instructions, which, when executed individually or collectively by one or more processors of a computing device, cause the computing device to execute the method in the above embodiment.

[0028] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0030] Figure 1 A schematic diagram of the exploded structure of a battery according to some embodiments of the present application; Figure 2 A schematic diagram of the exploded structure of a battery cell according to some embodiments of the present application; Figure 3 This is one of the flow charts of the temperature control method of some embodiments of the present application; Figure 4 This is one of the schematic diagrams of multiple sub-regions on the surface of a battery cell in some embodiments of the present application; Figure 5 This is a second schematic diagram of multiple sub-regions on the surface of a battery cell in some embodiments of the present application; Figure 6 This is a second flow chart of the temperature control method of some embodiments of the present application; Figure 7 This is a third flow chart of the temperature control method of some embodiments of the present application; Figure 8 This is a fourth flow chart of the temperature control method of some embodiments of the present application; Fig. 9 This is a fifth flow chart of the temperature control method of some embodiments of the present application; Fig.10 An exemplary block diagram of a test device according to some embodiments of the present application; Fig.11 This is one of the schematic diagrams of the testing device of some embodiments of the present application; Fig.12 This is the second schematic diagram of the testing device of some embodiments of the present application; Fig.13 This is a schematic diagram of the structure of the temperature acquisition module in some embodiments of the present application; Fig.14 is a block diagram of an exemplary computing device that can be used with the exemplary embodiments.

[0031] Description of reference numerals: Computing device 1000 , display device 1001 , communication interface 1002 , other input / output (I / O) devices 1003 , bus 1004 , processor 1005 , mass storage device 1006 , memory 1007 , operating system 1008 , application program 1009 , other programs 1010 , program data 1011 ; Testing device 200, first temperature acquisition module 210, second temperature acquisition module 220, adjustment module 230; Battery 100, sub-region 101, temperature acquisition unit 102; Box body 10, first part 11, second part 12; Battery cell 20, end cap 21, electrode terminal 21a, housing 22, electrode assembly 23, and tab 23a; Detection line 1, transmission line 2. DETAILED DESCRIPTION

[0032] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0034] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0035] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0036] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0037] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0038] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0039] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0040] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0041] The internal resistance of the battery is an important parameter for feedback of battery performance, and temperature has a great influence on the internal resistance of the battery. Based on this, it is necessary to place the battery in a set temperature environment and test the battery to evaluate the battery performance. During the test process, the accuracy of temperature control is required to be high.

[0042] In the related art, a thermostat is used to control the temperature, but the temperature control efficiency of the thermostat is low and the accuracy is poor, which may cause the problem of uneven battery temperature.

[0043] In addition, the battery can be placed in a water bath and the temperature of the battery can be controlled by the flow of circulating water in the water bath. However, since some areas of the battery will generate heat during the test, the temperature distribution on the battery surface is uneven, and the temperature of the circulating water cannot be maintained at the set temperature as the test progresses, resulting in reduced validity of the test results.

[0044] Based on the above considerations, a battery testing method is designed, including: obtaining the maximum value of the temperature difference between each sub-area as the first temperature difference; obtaining the second temperature difference between the actual temperature of the circulating fluid and the set temperature; when either the first temperature difference or the second temperature difference is greater than a preset value, adjusting the temperature of the circulating fluid, and / or adjusting the flow rate of the circulating fluid; wherein all the above steps are recorded as one temperature adjustment, and N temperature adjustments are performed so that the obtained first temperature difference and the second temperature difference are both less than the preset value, and N is an integer greater than or equal to 1.

[0045] By performing the temperature adjustment N times, the first temperature difference and the second temperature difference can be continuously obtained, and based on the fact that either of the first temperature difference and the second temperature difference is greater than the preset value, the temperature and / or flow rate of the circulating fluid is continuously adjusted so that the first temperature difference and the second temperature difference obtained are both less than the preset value. In this way, the maximum value of the temperature difference between each sub-area on the surface of the battery cell is less than the preset value, and while achieving the improvement of the uniformity of the surface temperature of the battery cell, the temperature of the circulating fluid can be controlled to approach or reach the set temperature, so that the temperature of the battery cell immersed in the circulating fluid is also close to or reaches the set temperature, thereby improving the validity of the test results.

[0046] The battery disclosed in the embodiment of the present application can be used in, but not limited to, electrical devices such as vehicles, ships or aircraft. A power supply system comprising the battery disclosed in the present application can be used to form the electrical device, which is conducive to improving the stability of battery performance and battery life.

[0047] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0048] Please refer to Figure 1 , Figure 1Schematic diagram of the exploded structure of the battery provided for some embodiments of the present application. The battery 100 includes a housing 10 and a battery cell 20, and the battery cell 20 is accommodated in the housing 10. Among them, the housing 10 is used to provide a storage space for the battery cell 20, and the housing 10 can adopt a variety of structures. In some embodiments, the housing 10 may include a first part 11 and a second part 12, and the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cell 20.

[0049] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in mixed connection, where mixed connection means that the multiple battery cells 20 are connected in series and in parallel. The battery 100 may also include other structures, for example, the battery 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0050] Each battery cell 20 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0051] Please refer to Figure 2 , Figure 2 The schematic diagram of the decomposition structure of a battery cell provided in some embodiments of the present application. A battery cell 20 refers to the smallest unit that constitutes a battery. Figure 2 The battery cell 20 includes an end cover 21, a shell 22, an electrode assembly 23 and other functional components.

[0052] The end cap 21 is a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment. Functional components such as electrode terminals 21a may be provided on the end cap 21. The electrode terminals 21a may be used to electrically connect to the electrode assembly 23 to output or input electrical energy of the battery cell 20.

[0053] The housing 22 is a component used to cooperate with the end cover 21 to form an internal environment of the battery cell 20 , wherein the formed internal environment can be used to accommodate the electrode assembly 23 , electrolyte and other components.

[0054] The electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 23 may be included in the housing 22. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly, and the parts of the positive and negative electrode sheets without active materials each constitute a tab 23a. The positive tab and the negative tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the tab 23a connects the electrode terminals to form a current loop.

[0055] refer to Figures 3 to 5 , the embodiment of the present application provides a battery testing method, the temperature control method includes: Step 110, obtaining the maximum value of the temperature difference between each sub-region 101 on the surface of the battery cell as a first temperature difference, wherein each sub-region is a different region on the surface of the battery cell; Step 120, obtaining a second temperature difference between the actual temperature of the circulating fluid and the set temperature, wherein the battery cell is placed in the circulating fluid for testing; Step 130: When either the first temperature difference or the second temperature difference is greater than a preset value, adjust the temperature of the circulating fluid and / or adjust the flow rate of the circulating fluid.

[0056] Among them, steps 110 to 130 are recorded as one temperature adjustment, and temperature adjustment is performed N times so that the temperature difference between each sub-area 101 and the temperature difference between the actual temperature of the circulating fluid and the set temperature are both less than the preset value, and N is an integer greater than or equal to 1.

[0057] The battery cell is placed in a test chamber with circulating liquid for testing. The circulating liquid refers to a liquid that can circulate in the test chamber. Exemplarily, the test chamber may include a liquid inlet and a liquid outlet arranged on different sides and opposite to each other. The circulating liquid continuously flows into the test chamber from the liquid inlet and flows out from the liquid outlet to form a flow. The battery cell is immersed in the circulating liquid so that the temperature of the battery cell is the same as or close to the temperature of the circulating liquid. By controlling the temperature of the circulating liquid to be the set temperature, the temperature of the battery cell that can be located in the circulating liquid is also close to or equal to the set temperature, thereby controlling the test temperature of the battery.

[0058] The inflow speed of the circulating liquid from the liquid inlet and the outflow speed from the liquid outlet can be close to or the same, so that the volume of the circulating liquid in the test cavity remains substantially unchanged. For example, a liquid supply pump and a liquid extraction pump can be respectively provided at the liquid inlet and the liquid outlet, the liquid supply pump is used to pump the circulating liquid from the liquid inlet into the test cavity, and the liquid extraction pump is used to extract the circulating liquid from the liquid outlet, thereby forming a flow. The rotation speed of the liquid supply pump can be the same as the rotation speed of the liquid extraction pump, so as to control the inflow speed of the circulating liquid from the liquid inlet and the outflow speed from the liquid outlet to be close to or the same.

[0059] In some embodiments, the circulating liquid may be circulating water, the liquid supply pump may be a water supply pump, and the liquid suction pump may be a water suction pump.

[0060] The surface of the battery cell may be the shell surface of the battery cell. The battery cell may include four faces connected in sequence, namely, a first face, a second face, a third face, and a fourth face connected in sequence, wherein the first face is arranged opposite to the third face, the second face is arranged opposite to the fourth face, and the surface areas of the first face and the third face are both greater than the areas of the second face and the fourth face. Exemplarily, the battery cell may be in the shape of a cuboid, and the first face, the second face, the third face, and the fourth face are respectively four side faces of the cuboid connected in sequence.

[0061] Figure 4 and Figure 5 FIG. 4 shows a surface of a battery cell divided into a plurality of sub-regions. Figure 4 as well as Figure 5 As shown, the plurality of sub-regions 101 may be arranged in an array, in a plurality of rows and a plurality of columns.

[0062] In some embodiments, at least part of the first surface or the third surface of the battery cell may be divided into a plurality of sub-areas 101. This is because the first surface and the third surface are opposite to each other, and the temperature distribution of the two surfaces is similar, and the first surface and the third surface are surfaces with larger areas in the battery cell, and the uneven temperature distribution basically occurs in the first surface and the third surface. Based on this, by selecting at least part of the first surface or the third surface to be divided into a plurality of sub-areas 101, the temperature distribution of the battery cell can be obtained.

[0063] like Figure 4 As shown, in some embodiments, the entire first surface or the third surface of the battery cell may be divided into a plurality of sub-regions 101 .

[0064] like Figure 5As shown, in other embodiments, only part of the first surface or the third surface of the battery cell may be divided into a plurality of sub-areas 101. For example, taking the first surface as an example, the first surface includes a central area and a peripheral area arranged around the periphery of the central area, and the central area of ​​the first surface may be divided into a plurality of sub-areas 101. This is because the self-heating phenomenon of the part close to the center of the battery cell is more serious, and the phenomenon of uneven temperature distribution there is also more serious.

[0065] In step 110, the temperature difference between each sub-region 101 refers to the temperature difference between every two sub-regions in the multiple sub-regions 101. For example, when the number of sub-regions is three, namely the first sub-region, the second sub-region and the third sub-region, the temperature difference between each sub-region is: the temperature difference between the first sub-region and the second sub-region, the temperature difference between the first sub-region and the third sub-region, and the temperature difference between the second sub-region and the third sub-region, and the maximum value of these three temperature differences is the first temperature difference. In some embodiments, when the battery cell is placed in the circulating fluid, the temperature of each sub-region can be detected by multiple temperature sensors.

[0066] In step 120, the set temperature may be the test temperature to be reached. During the test, the temperature of the circulating fluid is controlled to be maintained at the set temperature so that the temperature of the battery cell can also be maintained near the set temperature, thereby improving the validity of the test results. In some embodiments, a temperature sensor may be placed in the circulating fluid, for example, a thermocouple may be placed in the circulating fluid to detect the actual temperature of the circulating fluid.

[0067] Step 110 and step 120 may be executed simultaneously, or step 110 may be executed before step 120 , or step 120 may be executed before step 110 .

[0068] In step 130, the preset value may be a threshold value of the temperature difference. Since the first temperature difference is the maximum temperature difference between each sub-area on the surface of the battery cell, when the first temperature difference and the second temperature difference are both less than the preset value, the temperature on the surface of the battery cell is relatively uniform, and the temperature of the circulating fluid is close to or equal to the set temperature.

[0069] In some embodiments, the preset value may be 0.5°C. It is worth noting that the first temperature difference and the second temperature difference are both absolute values ​​of the temperature difference. For example, if the temperature of one of the two sub-areas is 5°C and the temperature of the other sub-area is 10°C, the first temperature difference is 5°C. If the temperature of the circulating fluid is -5°C and the set temperature is 5°C, the second temperature difference is 10°C.

[0070] It is understandable that the first temperature difference and the second temperature difference may be different or the same. When both are greater than a preset value, the temperature of the circulating fluid and / or the flow rate of the circulating fluid are adjusted according to either the first temperature difference or the second temperature difference.

[0071] Performing N temperature adjustments so that the temperature difference between each sub-area and the temperature difference between the actual temperature of the circulating fluid and the set temperature are both less than the preset value means: after executing step 130, executing steps 110 and 120 again to re-acquire the first temperature difference and the second temperature difference, and if either of the re-acquired first temperature difference and the second temperature difference is still the preset value, executing step 130 until the temperature difference between each sub-area and the temperature difference between the actual temperature of the circulating fluid and the set temperature are both less than the preset value. If after performing one temperature adjustment, executing steps 110 and 120 again to re-acquire the first temperature difference and the second temperature difference are both less than the preset value, step 130 does not need to be performed. That is, only one temperature adjustment is required.

[0072] It is understandable that, each time step 130 is performed, when the first temperature difference and the second temperature difference are obtained again, the two sub-regions forming the first temperature difference may be the same as the two sub-regions forming the first temperature difference when the temperature adjustment was performed last time, or they may be different. The value of the first temperature difference may be the same or different. In addition, the magnitude relationship between the first temperature difference and the second temperature difference may also change, or it may not change.

[0073] Exemplarily, when performing the first temperature adjustment, the temperature difference between the first sub-region and the third sub-region is the largest, that is, the temperature difference between the first sub-region and the third sub-region is used as the first temperature difference. After performing the first temperature adjustment, the temperature of each sub-region is obtained again. If the temperature difference between the first sub-region and the third sub-region is reduced but still the largest, the temperature difference between the first sub-region and the third sub-region is still used as the first temperature difference. If the temperature difference between the first sub-region and the third sub-region is less than the temperature difference between the first sub-region and the second sub-region, the temperature difference between the first sub-region and the second sub-region is used as the first temperature difference. The first temperature difference obtained again may be less than the second temperature difference, or may be greater than the first temperature difference. As long as either of the first temperature difference and the second temperature difference obtained again is greater than the preset value, step 130 needs to be executed. After each execution of step 130, the first temperature difference and the second temperature difference are re-obtained until the first temperature difference and the second temperature difference are both less than the preset value.

[0074] As can be seen from the above, in the embodiment of the present application, it is possible to make the newly acquired first temperature difference and the second temperature difference both less than the preset value by performing only one temperature adjustment, or it is possible to make the newly acquired first temperature difference and the second temperature difference both less than the preset value by performing multiple temperature adjustments. However, no matter how many times the temperature adjustment is performed, the method of the embodiment of the present application can eventually make the first temperature difference and the second temperature difference less than the preset value.

[0075] In some embodiments, the circulating fluid may be heated by a heater to increase the temperature of the circulating fluid, and the circulating fluid may be cooled by a cooler to reduce the temperature of the circulating fluid.

[0076] Adjusting the flow rate of the circulating liquid refers to adjusting the flow rate of the circulating liquid flowing into the liquid inlet, and the flow rate of the circulating liquid flowing into the liquid inlet can be adjusted by adjusting the rotation speed of the liquid supply pump. For example, the flow rate of the circulating liquid can be increased by increasing the rotation speed of the liquid supply pump, or the flow rate of the circulating liquid can be reduced by reducing the rotation speed of the liquid supply pump.

[0077] In the above technical solution, by performing N times of temperature adjustment, the first temperature difference and the second temperature difference can be continuously obtained, and based on the fact that either of the first temperature difference and the second temperature difference is greater than the preset value, the temperature and / or flow rate of the circulating fluid is continuously adjusted so that the obtained first temperature difference and the second temperature difference are both less than the preset value. In this way, the maximum value of the temperature difference between each sub-area on the surface of the battery cell is less than the preset value, and while achieving the improvement of the uniformity of the surface temperature of the battery cell, the temperature of the circulating fluid can be controlled to approach or reach the set temperature, so that the temperature of the battery cell immersed in the circulating fluid is also close to or reaches the set temperature, thereby improving the validity of the test results.

[0078] refer to Figure 6 According to some embodiments of the present application, step 130 includes: Step 131, when either the first temperature difference or the second temperature difference is greater than a preset value, the larger one of the first temperature difference and the second temperature difference is used as a temperature deviation value; Step 132: Based on the temperature deviation value, the temperature of the circulating fluid is adjusted by a first feedback control algorithm, and / or the flow rate of the circulating fluid is adjusted by a second feedback control algorithm.

[0079] The first feedback control algorithm and the second feedback control algorithm may both be PID (Proportion Integral Differential) closed-loop control algorithms. The PID closed-loop control algorithm is a control algorithm that combines the three links of proportion, integration and differentiation, which has the same meaning as that generally understood by technicians in the technical field of this application. The calculation coefficients of the first feedback control algorithm and the second feedback control algorithm may be different, and the calculation coefficients refer to the proportional gain, integral proportional constant and differential proportional constant of the PID closed-loop control algorithm.

[0080] In some embodiments, the temperature of the circulating fluid may be adjusted by a first feedback control algorithm so that the temperature of the circulating fluid increases or decreases by a temperature deviation value to reduce the first temperature difference or the second temperature difference that forms the temperature deviation value.

[0081] In other embodiments, the flow rate of the circulating fluid may be adjusted by a second feedback control algorithm so that the temperature of the circulating fluid increases or decreases by a temperature deviation value to reduce the first temperature difference or the second temperature difference that forms the temperature deviation value.

[0082] In some other embodiments, the temperature of the circulating fluid may be adjusted by a first feedback control algorithm, and the flow rate of the circulating fluid may be adjusted by a second feedback control algorithm simultaneously, so as to reduce the first temperature difference or the second temperature difference that forms the temperature deviation value.

[0083] In the above technical solution, based on the actual temperature deviation value, a feedback control algorithm is used to adjust the temperature and / or flow rate of the circulating fluid to reduce the first temperature difference and the second temperature difference, which can improve the temperature control effect.

[0084] According to some embodiments of the present application, adjusting the temperature of the circulating fluid by a first feedback control algorithm based on the temperature deviation value includes: Based on the temperature deviation value, determining a target temperature of the circulating fluid; The temperature of the circulating fluid is adjusted by a first feedback control algorithm based on the target temperature and the actual temperature of the circulating fluid.

[0085] The target temperature is the temperature that the circulating fluid will eventually reach when one temperature adjustment is completed.

[0086] In one temperature adjustment, the temperature of the circulating fluid can be adjusted by the first feedback control algorithm only based on the target temperature and the actual temperature of the circulating fluid until the temperature of the circulating fluid reaches the target temperature. For example, the temperature of the circulating fluid can be adjusted by a heater or a cooler so that the temperature of the circulating fluid reaches the target temperature. Based on the target temperature and the actual temperature of the circulating fluid, the difference between the target temperature and the actual temperature of the circulating fluid can be input as a deviation into the first feedback control algorithm, and the temperature of the circulating fluid can be adjusted based on the output value of the first feedback control algorithm. The actual temperature of the circulating fluid referred to here is the current actual temperature of the circulating fluid, and the current actual temperature of the circulating fluid is the real-time temperature of the circulating fluid during the process of adjusting the temperature of the circulating fluid by the first feedback control algorithm. It can be understood that it is usually necessary to adjust the target temperature by the first feedback control algorithm for multiple times, that is, after each adjustment of the temperature of the circulating fluid based on the output value of the first feedback control algorithm, the current actual temperature of the circulating fluid at this time is obtained, and the deviation between the current actual temperature and the target temperature is input into the first feedback control algorithm again, and the temperature of the circulating fluid is adjusted again based on the output value of the first feedback control algorithm until the temperature of the circulating fluid reaches the target temperature.

[0087] Exemplarily, the first feedback control algorithm is a PID closed-loop control algorithm, and the first feedback control algorithm can be executed by the following formula (1).

[0088] (1) in, represents the output value of the first feedback control algorithm as a function of time, represents the proportional gain of the first feedback control algorithm, represents the integral proportional constant of the first feedback control algorithm, represents the differential proportional constant of the first feedback control algorithm, represents the deviation between the target temperature of the circulating fluid and the current actual temperature of the circulating fluid, and n represents the number of times the temperature of the circulating fluid is adjusted based on the first feedback control algorithm in one temperature adjustment.

[0089] The proportional gain, integral proportional constant and differential proportional constant of the first feedback control algorithm may be set based on experience, or may be adjusted in real time based on the response during the process of regulating the temperature of the circulating fluid.

[0090] In the above technical solution, the temperature deviation value is used as the basis for determining the target temperature of the circulating fluid, which can more specifically reduce the maximum temperature difference between the various sub-areas on the surface of the battery cell, as well as the temperature difference between the circulating fluid and the set temperature, thereby improving the temperature regulation efficiency.

[0091] like Figure 7 As shown, according to some embodiments of the present application, the first temperature difference is used as a temperature deviation value, and based on the temperature deviation value, determining the target temperature of the circulating fluid includes: Step 1321, obtaining the current temperature of the circulating fluid, where the current temperature is the actual temperature of the circulating fluid at the time when the temperature deviation value is obtained; Step 1322, obtaining a target temperature based on the current temperature and the temperature deviation value.

[0092] The second temperature difference is used as a temperature deviation value, and based on the temperature deviation value, determining a target temperature of the circulating fluid includes: The set temperature is used as the target temperature.

[0093] In step 1321, the moment of obtaining the temperature deviation value is the moment of obtaining the first temperature difference. In some embodiments, the current temperature of the circulating fluid can be obtained by a temperature sensor placed in the circulating fluid.

[0094] In step 1321, the sum or difference of the current temperature and the temperature deviation value may be used as the target temperature.

[0095] In the embodiment of the present application, when the first temperature difference is used as the temperature deviation value, the temperature of the circulating fluid is adjusted based on the maximum temperature difference between each sub-region on the surface of the battery cell, so that the temperature of each sub-region on the surface of the battery cell can change to different degrees to reduce the maximum temperature difference between each sub-region on the surface of the battery cell. Since the temperature of each sub-region on the surface of the battery cell is not directly adjusted, but the temperature of the circulating fluid is adjusted to indirectly reduce the maximum temperature difference between each sub-region, after performing one temperature adjustment, even if the temperature of the circulating fluid reaches the target temperature, the first temperature difference will not immediately decrease below the preset value. Based on this, the embodiment of the present application performs N temperature adjustments, and each time the temperature adjustment is performed, the first temperature difference and the second temperature difference are obtained. As long as either the first temperature difference and the second temperature difference is greater than the preset value, step 130 is performed until the first temperature difference and the second temperature difference are both less than the preset value.

[0096] It is understandable that if each sub-region of the battery cell surface is directly adjusted, a temperature adjustment device needs to be provided in each sub-region of the battery cell surface, which not only makes the equipment complicated, but also makes it more likely to cause uneven temperature when adjusting the temperature through multiple temperature adjustment devices.

[0097] Based on the above considerations, in the embodiment of the present application, the temperature of the circulating fluid is adjusted based on the maximum temperature difference of each sub-area on the surface of the battery cell. Taking the actual maximum temperature difference as the basis, it can avoid to a certain extent the problem that the overall temperature of the battery cell deviates too much from the set temperature due to excessive adjustment of the temperature of the circulating fluid. It can also avoid to a certain extent the problem that the effect is minimal due to too small adjustment of the temperature of the circulating fluid.

[0098] The second temperature difference is the difference between the actual temperature of the circulating fluid and the set temperature. Therefore, when the second temperature difference is used as the temperature deviation value, the set temperature is used as the target temperature, so that the temperature of the circulating fluid can reach the set temperature after step 130. It can be understood that when step 130 is performed based on the second temperature difference, the temperature of the circulating fluid is adjusted based on the difference between the actual temperature of the circulating fluid and the set temperature, so that the temperature deviation value can be eliminated by performing step 130 only once, thereby making the temperature of the circulating fluid reach the set temperature.

[0099] In the above technical solution, when the first temperature difference is used as the temperature deviation value, the current temperature of the circulating fluid can be adjusted based on the temperature deviation value, so as to effectively control the maximum temperature difference between each sub-area on the current battery cell surface, thereby improving the temperature uniformity of the battery cell surface. When the second temperature difference is used as the temperature deviation value, the set temperature is used as the target temperature to adjust the temperature of the circulating fluid to be close to or equal to the set temperature, so that the temperature of the battery cell immersed in the circulating fluid can also be close to or reach the set temperature, thereby improving the validity of the test results.

[0100] According to some embodiments of the present application, step 1322 may include: taking the sum of the current temperature and the temperature deviation value as the target temperature.

[0101] In other words, the actual temperature of the current circulating fluid is increased by the temperature deviation value to reach the target temperature. It is understandable that the reason for the temperature difference on the surface of the battery cell is usually due to the serious self-heating of some parts of the battery cell, which makes the temperature of this area higher than the temperature of the circulating fluid, and the area with lower temperature is immersed in the circulating fluid and is closer to the temperature of the circulating fluid. Therefore, in the process of heating the circulating fluid to the target temperature, the circulating fluid transfers heat to the battery cell, so that the sub-area with the lowest temperature among the various sub-areas on the surface of the battery cell increases with the increase of the temperature of the circulating fluid, and the increased temperature is close to or equal to the temperature deviation value. Since the temperature of the highest sub-region among the sub-regions on the surface of the battery cell is usually higher than the current temperature of the circulating fluid, for example, the difference between the temperature of the highest sub-region among the sub-regions on the surface of the battery cell and the current temperature of the circulating fluid is equal to or greater than the temperature deviation value, then in the process of heating the circulating fluid to the target temperature, the temperature of the circulating fluid is always lower than the temperature of the highest sub-region, so that the circulating fluid will not transfer heat to the highest point during the heating process, so that the highest point does not rise in temperature or the temperature rise is small, thereby achieving the purpose of reducing the maximum temperature difference between the sub-regions; for another example, the temperature of the highest sub-region among the sub-regions on the surface of the battery cell is higher than the current temperature of the circulating fluid, but the temperature difference is smaller than the temperature deviation value, then in the process of heating the circulating fluid to the target temperature, only when the temperature of the circulating fluid is higher than the temperature of the highest point, will the circulating fluid transfer heat to the highest point, so that the temperature rise of the highest sub-region among the sub-regions on the surface of the battery cell is smaller than the temperature rise of the lowest sub-region, thereby achieving the purpose of reducing the maximum temperature difference between the sub-regions.

[0102] By taking the sum of the current temperature and the temperature deviation value as the target temperature, the temperature of the sub-region with the lowest temperature among the sub-regions on the surface of the battery cell can be raised so that its temperature approaches or reaches the temperature of the sub-region with the highest temperature among the sub-regions, thereby reducing the temperature difference between the sub-regions. In this way, the overall temperature of the surface of the battery cell is raised. If the maximum temperature of each sub-region on the surface of the battery cell is greater than the set temperature, the overall temperature of the battery cell will be greater than the set temperature after the temperature of the surface of the battery cell is equalized. In this case, by performing temperature adjustment N times in the embodiment of the present application, the second temperature difference can be controlled to be less than the preset value, so that the temperature of the circulating fluid can be maintained near the set temperature, thereby cooling the entire battery cell and returning the overall temperature of the battery cell to near the set temperature.

[0103] In the above technical solution, by taking the sum of the current temperature and the temperature deviation value as the target temperature, the temperature rise of the sub-region with the lowest temperature among the sub-regions is not greater than the temperature deviation value, and the temperature rise of the sub-region with the highest temperature among the sub-regions is less than the temperature rise of the sub-region with the lowest temperature. Therefore, the maximum temperature difference between the sub-regions can be effectively reduced to below the temperature deviation value.

[0104] According to some embodiments of the present application, step 1322 may also include: When the larger of the temperatures of the two sub-areas forming the first temperature difference is greater than the set temperature, the difference between the current temperature and the temperature deviation value is used as the target temperature; When the larger of the temperatures of the two sub-areas forming the first temperature difference is lower than the set temperature, the sum of the current temperature and the temperature deviation value is taken as the target temperature.

[0105] The two sub-regions forming the first temperature difference are the sub-region with the highest temperature and the sub-region with the lowest temperature among the sub-regions.

[0106] If the temperature of the highest temperature sub-region among the sub-regions is greater than the set temperature, the temperature obtained by subtracting the temperature deviation value from the current temperature is used as the target temperature. In the process of cooling the circulating fluid, the temperature difference between the highest temperature sub-region among the sub-regions and the circulating fluid is greater than the temperature difference between the lowest temperature sub-region among the sub-regions, so that the heat exchange rate between the circulating fluid and the highest temperature sub-region among the sub-regions is greater than the heat exchange rate between the circulating fluid and the lowest temperature sub-region. In this way, the temperature drop rate of the highest temperature sub-region is greater than the temperature drop rate of the lowest temperature sub-region, thereby reducing the maximum temperature difference between the sub-regions.

[0107] If the temperature of the lowest sub-region among the sub-regions is lower than the set temperature, the temperature after adding the temperature deviation value to the current temperature is used as the target temperature. In the process of heating the circulating fluid, the temperature rise of the lowest sub-region among the sub-regions is greater than the temperature rise of the highest sub-region, so as to reduce the maximum temperature difference between the sub-regions.

[0108] In the above technical solution, after repeated temperature adjustment, the first temperature difference can be adjusted to be less than the preset value, and during the adjustment process, the overall temperature of the battery cell can be controlled near the set temperature, which is conducive to achieving a better temperature control effect on the battery cell.

[0109] According to some embodiments of the present application, adjusting the flow rate of the circulating fluid by a second feedback control algorithm based on the temperature deviation value includes: determining a first target flow rate of the circulating fluid based on the temperature deviation value; Based on the first target flow rate and the actual flow rate of the circulating fluid, the temperature of the circulating fluid is adjusted by a second feedback control algorithm.

[0110] The flow rate of the circulating fluid can affect the temperature of the circulating fluid. When the flow rate of the circulating fluid is too low, the heat generated during the battery cell test cannot be removed in time, causing the temperature of the circulating fluid to rise. When the flow rate of the circulating fluid is too high, the temperature of the circulating fluid flowing into the liquid inlet is low, which can cause the overall temperature of the circulating fluid to be too low.

[0111] That is, there is a certain relationship between the temperature and flow rate of the circulating fluid. Based on this, the first target flow rate of the circulating fluid can be determined based on the temperature deviation value, so that the temperature of the circulating fluid can change by the temperature deviation value when one temperature adjustment is completed.

[0112] In one temperature adjustment, the flow rate of the circulating fluid can be adjusted by the second feedback control algorithm only based on the first target flow rate and the actual flow rate of the circulating fluid until the circulating fluid reaches the first target flow rate. There is a corresponding relationship between the rotation speed of the liquid supply pump and the flow rate, and the flow rate of the circulating fluid can be adjusted by adjusting the rotation speed of the liquid supply pump.

[0113] Based on the first target flow rate and the actual flow rate of the circulating liquid, the difference between the first target flow rate of the circulating liquid and the actual flow rate of the circulating liquid can be input as a deviation into the second feedback control algorithm, and the flow rate of the circulating liquid is adjusted based on the output value of the second feedback control algorithm. The actual flow rate of the circulating liquid referred to here is the current actual flow rate of the circulating liquid, and the current actual flow rate of the circulating liquid is the real-time flow rate of the circulating liquid in the process of adjusting the flow rate of the circulating liquid by the second feedback control algorithm. It can be understood that it is usually necessary to make multiple adjustments through the second feedback control algorithm to finally reach the first target flow rate, that is, after each adjustment of the flow rate of the circulating liquid based on the output value of the second feedback control algorithm, the current actual flow rate of the circulating liquid at this time is obtained, and the deviation between the current actual flow rate and the first target flow rate is input again into the second feedback control algorithm, and the flow rate of the circulating liquid is adjusted again based on the output value of the second feedback control algorithm until the flow rate of the circulating liquid reaches the target flow rate.

[0114] Exemplarily, the second feedback control algorithm may be a PID closed-loop control algorithm, and the second feedback control algorithm may be executed by the following formula (2).

[0115] (2) in, represents the output value of the second feedback control algorithm as a function of time, represents the proportional gain of the second feedback control algorithm, represents the integral proportional constant of the second feedback control algorithm, represents the differential proportional constant of the second feedback control algorithm, represents the deviation between the first target flow rate of the circulating fluid and the current actual flow rate of the circulating fluid, and n represents the number of times the flow rate of the circulating fluid is adjusted based on the first feedback control algorithm in one temperature adjustment.

[0116] The proportional gain, integral proportional constant and differential proportional constant of the second feedback control algorithm may be set based on experience, or may be adjusted in real time based on the response during the process of regulating the flow of the circulating fluid.

[0117] In some embodiments, the actual flow rate of the circulating fluid may be obtained by a flow meter.

[0118] In the above technical solution, the first target flow rate is determined based on the temperature difference deviation value, so that after the flow rate is adjusted to the first target flow rate, the first temperature difference or the second temperature difference can be reduced. In the embodiment of the present application, both the flow rate adjustment of the circulating fluid and the temperature adjustment of the circulating fluid can be used to diversify the adjustment methods. In the case that any adjustment method fails, other adjustment methods can be used to improve the reliability of temperature control.

[0119] like Figure 8 As shown, according to some embodiments of the present application, determining the first target flow rate of the circulating fluid based on the temperature deviation value includes: Step 1323, obtaining a first mapping relationship, the first mapping relationship is used to represent the flow rate required to increase or decrease when the temperature of the circulating fluid changes by P degrees, where P is a real number; Step 1324, determining a first change value of the flow rate of the circulating fluid according to the temperature deviation value and the first mapping relationship; Step 1325, obtaining a first current flow rate of the circulating fluid, where the first current flow rate is the actual flow rate of the circulating fluid at the moment when the temperature deviation value is obtained; Step 1326, obtaining a first target flow rate based on the first current flow rate and the first change value.

[0120] In step 1323, the first mapping relationship can be obtained by experiments in advance. For example, P can be 1 degree, and based on the first mapping relationship, it can be obtained that the flow rate needs to be reduced by 1L / min when the temperature of the circulating fluid increases by 1 degree, and the flow rate needs to be increased by 1L / min when the temperature of the circulating fluid decreases by 1 degree.

[0121] In step 1324, the flow value required to be increased or decreased corresponding to the temperature deviation value is found in the first mapping relationship as the first change value. The first change value is an absolute value. In actual operation, the flow can be increased or decreased by the first change value.

[0122] In step 1325, the first current flow rate is the flow rate value of the circulating fluid output by the liquid supply pump at the moment when the temperature deviation value is obtained.

[0123] In step 1326, the sum / difference of the first current flow rate and the first change value may be used as the first target flow rate.

[0124] When the first temperature difference is used as the temperature deviation value, the flow rate of the circulating fluid is adjusted based on the maximum temperature difference between the various sub-regions on the surface of the battery cell, so that the temperature of the circulating fluid decreases or increases the temperature deviation value, thereby enabling the temperature of the various sub-regions on the surface of the battery cell to change to different degrees, thereby reducing the maximum temperature difference between the various sub-regions on the surface of the battery cell.

[0125] In the above technical solution, the first current flow rate of the circulating fluid is adjusted based on the first mapping relationship and the temperature deviation value, so that the current temperature of the circulating fluid can change the temperature deviation value to effectively reduce the first temperature difference or the second temperature difference.

[0126] According to some embodiments of the present application, the first temperature difference is used as the temperature deviation value, and step 1324 may include: According to the temperature deviation value and the first mapping relationship, determining the flow rate required to increase the temperature of the circulating fluid to reduce the temperature deviation value as the first change value; Step 1326 may include: taking the sum of the first current flow rate and the first change value as the first target flow rate.

[0127] In other words, no matter what the temperature between the sub-regions on the surface of the battery cell is, when the first temperature difference is used as the temperature deviation value, the first current flow rate is increased by the first change value to reach the first target flow rate.

[0128] In the process of increasing the circulating liquid flow rate to reduce the circulating liquid temperature, the temperature difference between the sub-region with the highest temperature among the sub-regions on the surface of the battery cell and the circulating liquid is greater than the temperature difference between the sub-region with the lowest temperature and the circulating liquid. Therefore, the heat exchange rate between the sub-region with the highest temperature and the circulating liquid is faster than the heat exchange rate between the sub-region with the lowest temperature and the circulating liquid, so that the temperature drop rate of the sub-region with the highest temperature is greater than the temperature drop rate of the sub-region with the lowest temperature, thereby reducing the first temperature difference. In addition, by increasing the circulating liquid flow rate, the heat exchange between the circulating liquid and the sub-region with the highest temperature among the sub-regions on the surface of the battery cell can be further accelerated, thereby accelerating the heat dissipation of the sub-region with the highest temperature to further reduce the first temperature difference.

[0129] In the above technical solution, by taking the sum of the first current flow rate and the first change value as the first target flow rate, the heat dissipation of the sub-region with the highest temperature can be accelerated, so that the temperature drop of the sub-region with the lowest temperature is less than the temperature drop of the sub-region with the highest temperature, thereby effectively reducing the maximum temperature difference between the sub-regions to below the temperature deviation value.

[0130] According to some embodiments of the present application, the second temperature difference is used as the temperature deviation value, and step 1324 includes: When the actual temperature of the circulating fluid is lower than the set temperature, based on the temperature deviation value and the first mapping relationship, a first flow rate at which the temperature of the circulating fluid increases and the temperature deviation value decreases is determined as the first change value; When the actual temperature of the circulating fluid is greater than the set temperature, a second flow rate at which the temperature of the circulating fluid decreases and the temperature deviation value increases is determined as the first change value based on the temperature deviation value and the first mapping relationship.

[0131] That is to say, if the actual temperature of the circulating fluid is lower than the set temperature when the second temperature difference is obtained, the first flow rate required to increase the temperature deviation value is found in the first mapping relationship, and the first flow rate is used as the first change value. The result of subtracting the first change value from the first current flow rate of the circulating fluid is used as the first target flow rate.

[0132] If the actual temperature of the circulating fluid is greater than the set temperature when the second temperature difference is obtained, the first flow rate required to reduce the temperature deviation value is found in the first mapping relationship, and the first flow rate is used as the first change value. The result of adding the first current flow rate of the circulating fluid to the first change value is used as the first target flow rate.

[0133] In the above technical solution, the temperature of the circulating fluid can be accurately adjusted so that the temperature of the circulating fluid is close to or equal to the set temperature.

[0134] like Fig. 9 As shown, according to some embodiments of the present application, based on the temperature deviation value, adjusting the temperature of the circulating fluid by a first feedback control algorithm, and adjusting the flow rate of the circulating fluid by a second feedback control algorithm may include: Step 1327, determining a target temperature of the circulating fluid based on the temperature deviation value; Step 1328, obtaining a first output value of a first feedback control algorithm based on a deviation value between a target temperature of the circulating fluid and an actual temperature of the circulating fluid; Step 1329, adjusting the temperature of the circulating fluid based on the first output value; Step 1330, determining a second target flow rate of the circulating fluid based on the first output value; Step 1331, based on the second target flow rate and the actual flow rate of the circulating fluid, the flow rate of the circulating fluid is adjusted by a second feedback control algorithm.

[0135] The method for executing step 1327 may refer to the above description of determining the target temperature of the circulating fluid based on the temperature deviation value, which will not be described in detail here.

[0136] In step 1328, the deviation between the target temperature of the circulating fluid and the actual temperature of the circulating fluid is input into the above formula (1) to obtain a first output value.

[0137] In step 1329, the first output value is the value to be adjusted. For example, when the temperature of the circulating fluid needs to be increased to the target temperature, the first output value is 0.5, and the temperature of the circulating fluid is increased by 0.5 degrees, and the circulating fluid can be heated by the heater.

[0138] In step 1330, the flow rate required to achieve the first output value of the temperature change of the circulating fluid is determined as the second target flow rate.

[0139] In step 1331, the deviation value between the second target flow rate and the actual flow rate of the circulating fluid is input into the above formula (2), and the flow rate of the circulating fluid is adjusted based on the second output value of the above formula (2), which helps the flow rate of the circulating fluid reach the first output value as soon as possible.

[0140] It is understandable that in step 1328 and step 1329, the temperature of the circulating fluid is directly regulated, for example, by using a heater or a cooler to change the temperature of the circulating fluid to change the first output value. In step 1330 and step 1331, the temperature of the circulating fluid is changed by adjusting the flow rate of the circulating fluid to change the second output value, and the second output value is output as the target value with the second target flow rate corresponding to the first output value. Therefore, in the case of not executing step 1329, it is usually necessary to perform multiple adjustments through the second feedback control algorithm to finally reach the second target flow rate, so that the temperature of the circulating fluid changes to the first output value. In other words, if step 1329 is executed only once, the temperature of the circulating fluid can reach the change of the first output value. If step 1331 is executed only once, the temperature of the circulating fluid cannot reach the change of the first output value. In this way, it can avoid, to a certain extent, the uncontrollable change of the circulating fluid temperature due to the excessively fast change of the circulating fluid temperature when step 1329 and step 1331 are executed simultaneously.

[0141] Step 1330 and step 1331 are to assist the execution of step 1329. Step 1331 and step 1329 can be executed simultaneously so that the temperature of the circulating fluid can reach the change of the first output value as soon as possible. For example, if the first output value is 0.5, and the temperature of the circulating fluid needs to be increased by 0.5 degrees, the circulating fluid can be heated by the heater at the same time, and the flow rate of the circulating fluid corresponding to the second output value can be reduced until the temperature of the circulating fluid rises to 0.5 degrees. The temperature change of the circulating fluid can be monitored in real time by a temperature sensor placed in the circulating fluid.

[0142] It is understandable that it is usually necessary to make multiple adjustments through the first feedback control algorithm to finally reach the target temperature. Therefore, steps 1328 to 1331 can be repeated multiple times until the temperature of the circulating fluid reaches the target temperature. For example, if the temperature deviation value is 2 degrees, the temperature of the circulating fluid needs to be increased by 2 degrees. The first output value of the first feedback control algorithm is 0.5 degrees. After executing steps 1330 and 1331 to obtain the second output value, the temperature and flow of the circulating fluid are simultaneously regulated to increase the temperature by 0.5 degrees. At this time, it is necessary to increase the circulating fluid by 1.5 degrees. Then, step 1328 is executed again, and the 1.5 degrees is input into formula (1) to obtain a new first output value. The new first output value is 0.1 degrees. After executing steps 1330 and 1331 based on 0.1 degrees to obtain a new second output value, the temperature and flow of the circulating fluid are simultaneously regulated to increase the temperature by 0.1 degrees. The cycle is repeated until the temperature of the circulating fluid is increased by 2 degrees.

[0143] In the above technical solution, the temperature of the circulating fluid is used as the main control, and the temperature of the circulating fluid is regulated according to the first output value output by the first feedback control algorithm. At the same time, the second target flow rate of the circulating fluid is determined according to the first output value, and the flow rate of the circulating fluid is adjusted by the second feedback control algorithm to assist in temperature control, thereby improving the efficiency of regulating the temperature of the circulating fluid based on the first output value.

[0144] According to some embodiments of the present application, when the first mapping relationship is used to characterize the flow rate required to increase or decrease when the temperature of the circulating fluid changes by P degrees, step 1330 includes: Determine a second change value of the flow rate of the circulating fluid according to the first output value and the first mapping relationship; Obtaining a second current flow rate of the circulating fluid, where the second current flow rate is the actual flow rate of the circulating fluid at the moment when the first output value is obtained; The second target flow rate is acquired based on the second current flow rate and the second change value.

[0145] In the first mapping relationship, the flow rate reduction required to increase the temperature of the circulating fluid by the first output value is found as the second change value, or the flow rate increase required to decrease the temperature of the circulating fluid by the first output value is found as the second change value.

[0146] The second target flow rate is obtained based on the second current flow rate and the second change value. If the temperature of the circulating fluid needs to be increased by the first output value, the result of subtracting the second change value from the second current flow rate is used as the second target flow rate. If the temperature of the circulating fluid needs to be reduced by the first output value, the result of increasing the second current flow rate by the second change value is used as the second target flow rate.

[0147] In the above technical solution, the flow rate of the circulating fluid is adjusted based on the first mapping relationship and the first output value, so that the temperature of the circulating fluid can be adjusted simultaneously through temperature adjustment and flow adjustment to achieve the purpose of changing the first output value more quickly.

[0148] According to some embodiments of the present application, step 132 includes only one sub-stage, in which the temperature of the circulating fluid is regulated by a first feedback control algorithm based on the temperature deviation value, and the flow rate of the circulating fluid is regulated by a second feedback control algorithm; or, the temperature of the circulating fluid is regulated by a first feedback control algorithm based on the temperature deviation value; or, the flow rate of the circulating fluid is regulated by a second feedback control algorithm based on the temperature deviation value.

[0149] In the case of performing temperature adjustment N times, step 132 is performed N times, and in each step 132, the temperature of the circulating fluid is adjusted by the first feedback control algorithm based on the temperature deviation value, and the flow rate of the circulating fluid is adjusted by the second feedback control algorithm; or the temperature of the circulating fluid is adjusted by the first feedback control algorithm based on the temperature deviation value; or the flow rate of the circulating fluid is adjusted by the second feedback control algorithm based on the temperature deviation value. The execution method can refer to the relevant description of the above embodiment, and will not be repeated here.

[0150] In the above technical solution, during the entire adjustment process, the same control method is used for regulation, which simplifies the control method.

[0151] According to some embodiments of the present application, step 132 includes two consecutive sub-stages, in which in one sub-stage, the temperature of the circulating fluid is regulated by a first feedback control algorithm based on a temperature deviation value, or the flow rate of the circulating fluid is regulated by a second feedback control algorithm based on the temperature deviation value; in the other sub-stage, the temperature of the circulating fluid is regulated by a first feedback control algorithm based on the temperature deviation value, and the flow rate of the circulating fluid is regulated by a second feedback control algorithm.

[0152] In some embodiments, in step 132, a sub-stage of adjusting the temperature of the circulating fluid by a first feedback control algorithm based on the temperature deviation value, or adjusting the flow rate of the circulating fluid by a second feedback control algorithm based on the temperature deviation value may be first executed. If the temperature of the circulating fluid has not changed by the temperature deviation value after the first preset time, it indicates that a deviation has occurred in the method, and another sub-stage is executed, that is, adjusting the temperature of the circulating fluid by a first feedback control algorithm based on the temperature deviation value, and adjusting the flow rate of the circulating fluid by a second feedback control algorithm. The first preset time can be set based on experience.

[0153] In other embodiments, in step 132, the sub-stages of adjusting the temperature of the circulating fluid by the first feedback control algorithm based on the temperature deviation value and adjusting the flow rate of the circulating fluid by the second feedback control algorithm may also be first executed. If the temperature of the circulating fluid has not changed the temperature deviation value after the second preset time, it means that there is a deviation in this method, and then another sub-stage is executed, that is, the sub-stage of adjusting the temperature of the circulating fluid by the first feedback control algorithm or the sub-stage of adjusting the flow rate of the circulating fluid by the second feedback control algorithm based on the temperature deviation value is executed. Among them, the second preset time can be set according to experience.

[0154] In the above technical solution, different control methods are adopted in different sub-stages, and control can be performed according to different temperature conditions to improve the reliability of temperature control.

[0155] According to some embodiments of the present application, the method further includes: The calculation coefficients of the first feedback control algorithm are adjusted in response to the output value of the first feedback control algorithm; and / or the calculation coefficients of the second feedback control algorithm are adjusted in response to the output value of the second feedback control algorithm.

[0156] The first feedback control algorithm and the second feedback control algorithm may both be PID closed-loop control algorithms.

[0157] The calculation coefficients of the first feedback control algorithm are the proportional gain, the integral proportional constant and the differential proportional constant of the first feedback control algorithm.

[0158] The calculation coefficients of the second feedback control algorithm are the proportional gain, integral proportional constant and differential proportional constant of the second feedback control algorithm.

[0159] The adjustment logic of the calculation coefficients of the first feedback control algorithm and the calculation coefficients of the second feedback control algorithm may be the same, and the following description will be made by taking the adjustment of the calculation coefficients of the first feedback control algorithm as an example.

[0160] When the circulating fluid is regulated based on the first feedback control algorithm, if the output value of the first feedback control algorithm does not oscillate and the temperature of the circulating fluid changes too slowly, the proportional gain of the first feedback control algorithm needs to be increased. If the output value of the first feedback control algorithm oscillates, the integral proportional constant of the first feedback control algorithm needs to be increased, or the differential proportional constant of the first feedback control algorithm needs to be reduced.

[0161] In the above technical solution, the calculation coefficients of the first feedback control algorithm and the second feedback control algorithm are adjusted according to the output value, so as to optimize the control performance and improve the accuracy of temperature control.

[0162] like Fig.10As shown, an embodiment of the present application provides a test device 200 for battery testing, wherein the test device 200 includes a test cavity, into which a circulating fluid is passed, and the test cavity is used to accommodate a battery cell; a first temperature acquisition module 210, used to acquire the temperature of each sub-region on the surface of the battery cell, each sub-region being a different region on the surface of the battery cell; a second temperature acquisition module 220, used to acquire a second temperature difference between an actual temperature of the circulating fluid and a set temperature; an adjustment module 230, used to acquire the maximum value of the temperature difference between each sub-region as a first temperature difference based on the temperature of each sub-region, and to adjust the temperature of the circulating fluid and / or the flow rate of the circulating fluid when either the first temperature difference or the second temperature difference is greater than a preset value.

[0163] The first temperature acquisition module 210 , the second temperature acquisition module 220 and the adjustment module 230 can be used for temperature adjustment in the above embodiments, and for the sake of brevity, they are not described again here.

[0164] In the above technical solution, the temperature of the circulating fluid and / or the flow rate of the circulating fluid can be adjusted based on the first temperature difference or the second temperature difference through the adjustment module 230, so that the maximum value of the temperature difference between each sub-area on the surface of the battery cell is less than a preset value. While improving the uniformity of the surface temperature of the battery cell, the temperature of the circulating fluid can be controlled to approach or reach the set temperature, so that the temperature of the battery cell immersed in the circulating fluid also approaches or reaches the set temperature, thereby improving the validity of the test results.

[0165] According to some embodiments of the present application, the adjustment module 230 includes: a first controller, which is used to use the larger of the first temperature difference and the second temperature difference as the temperature deviation value when either of the first temperature difference and the second temperature difference is greater than a preset value, and adjust the temperature of the circulating fluid through a first feedback control algorithm based on the temperature deviation value; a second controller, which is used to use the larger of the first temperature difference and the second temperature difference as the temperature deviation value when either of the first temperature difference and the second temperature difference is greater than a preset value, and adjust the flow rate of the circulating fluid through a second feedback control algorithm based on the temperature deviation value.

[0166] The first controller and the second controller can obtain the temperature of each sub-region on the surface of the battery cell, and calculate the maximum temperature difference between each sub-region as the first temperature difference, and can also obtain the temperature of the circulating fluid, and calculate the second temperature difference between the circulating fluid and the set temperature, and can also compare the first temperature difference and the second temperature difference, and use the larger one of the first temperature difference and the second temperature difference as the temperature deviation value. Among them, the first controller can adjust the temperature of the circulating fluid through the first feedback control algorithm based on the temperature deviation value, and the second controller can adjust the flow rate of the circulating fluid through the second feedback control algorithm based on the flow deviation value. The first mapping relationship can be pre-stored in the second controller, and the second controller determines the first target flow rate of the circulating fluid based on the temperature deviation value, and adjusts the temperature of the circulating fluid through the second feedback control algorithm based on the deviation value between the first target flow rate and the actual flow rate of the circulating fluid.

[0167] In other words, the first controller and the second controller can execute step 131 and step 132 in the above embodiment. The execution method can refer to the relevant description of the above embodiment and will not be repeated here.

[0168] In some embodiments, step 131 and step 132 in the above embodiments may be performed only by the first controller.

[0169] In some other embodiments, step 131 and step 132 in the above embodiment may also be performed only by the second controller.

[0170] In some other embodiments, step 131 and step 132 in the above embodiment may be performed jointly by the first controller and the second controller. For example, step 1327 to step 1331 in the above embodiment may be performed.

[0171] Before the above step 131 and step 132 are performed by the first controller and the second controller, the set temperatures are firstly set in the first controller and the second controller, and the calculation parameters of the first controller and the second controller are initialized.

[0172] In some embodiments, the temperature of each sub-area and the temperature of the circulating fluid can be obtained through a temperature sensor, and the first controller and the second controller are connected in communication with the temperature sensor to receive the temperature of each sub-area and the temperature of the circulating fluid detected by the temperature sensor. It is worth noting that the second controller is also connected in communication with a flow meter to obtain the actual flow of the circulating fluid through the flow meter, and adjust the flow of the circulating fluid based on the deviation between the actual flow of the circulating fluid and the first target flow or the second target flow.

[0173] The first controller and the second controller may both be PID controllers. Fig.11 and Fig.122 and 3 respectively show the control principle of the first controller for closed-loop regulation of the temperature of the circulating fluid, and the control principle of the second controller for closed-loop regulation of the flow rate of the circulating fluid.

[0174] The first controller calculates the deviation value between the target temperature and the actual temperature of the circulating fluid detected by the temperature sensor through a first feedback control algorithm, and controls the heater or cooler to adjust the temperature of the circulating fluid based on the output value of the first feedback control algorithm, and circulates in sequence until the temperature of the circulating fluid reaches the target temperature.

[0175] The second controller calculates the deviation between the target flow rate and the actual flow rate of the circulating liquid detected by the flowmeter through a second feedback control algorithm, and controls the flow rate of the circulating liquid output by the liquid supply pump based on the output value of the second feedback control algorithm, and circulates in sequence until the flow rate of the circulating liquid reaches the target flow rate. The target flow rate can be the first target flow rate or the second target flow rate in the above embodiment.

[0176] In some embodiments, the test device 200 may further include a power module, the power module is communicatively connected to the first controller and the second controller, and the power module is also communicatively connected to the heater, the cooler, and the liquid supply pump, respectively. The power module is used to obtain the power of the heater or the cooler based on the output value of the first feedback control algorithm, so as to adjust the temperature of the circulating fluid based on the output value of the first feedback control algorithm. The power module is also used to obtain the rotation speed of the liquid supply pump based on the output value of the second feedback control algorithm, so as to adjust the flow rate of the circulating fluid based on the output value of the second feedback control algorithm.

[0177] In the above technical solution, based on the actual temperature deviation value, a feedback control algorithm is used to adjust the temperature and / or flow rate of the circulating fluid to reduce the first temperature difference and the second temperature difference, which can improve the temperature control effect.

[0178] like Fig.13 As shown, according to some embodiments of the present application, the temperature acquisition module includes: a plurality of temperature acquisition units 102, wherein the plurality of temperature acquisition units 102 are disposed in a one-to-one correspondence in a plurality of sub-areas for acquiring the temperature of each sub-area, wherein each temperature acquisition unit 102 is communicatively connected with the adjustment module 230 so that the adjustment module 230 receives the temperature value acquired by the temperature acquisition unit 102.

[0179] Exemplarily, both the first controller and the second controller are in communication connection with each temperature acquisition unit 102 , and are used to receive the temperature of the sub-area detected by each temperature acquisition unit 102 .

[0180] In some embodiments, the temperature acquisition unit 102 may include but is not limited to a thermocouple, wherein the thermocouple may include a detection line 1 and a transmission line 2, the end of the detection line 1 contacts the sub-area to detect the temperature of the sub-area, and the transmission line 2 connects the first controller and the second controller to transmit the detected temperature to the first controller and the second controller in the form of an electrical signal.

[0181] In the above technical solution, the temperature of each sub-area can be accurately acquired through multiple temperature acquisition units 102 to improve the accuracy of temperature control.

[0182] like Fig.14 As shown, an embodiment of the present application provides a computing device 1000, which includes at least one processor 1005; and at least one memory 1007 communicatively connected to the at least one processor 1005, and the at least one memory 1007 stores instructions, which, when executed individually or collectively by the at least one processor, enable the computing device 1000 to execute the method in the above embodiment.

[0183] The computing device 1000 may include at least one processor 1005, memory 1007, (multiple) communication interfaces 1002, display device 1001, other input / output (I / O) devices 1003, and one or more mass storage devices 1006 that can communicate with each other, such as through a system bus 1004 or other appropriate connection. The memory 1007 stores instructions that, when executed by the processor 1005, cause the processor 1005 to perform the method as described in the above embodiments. The computing device 1000 may be a variety of different types of devices. Examples of the computing device 1000 include, but are not limited to: desktop computers, server computers, laptop or netbook computers, mobile devices (e.g., tablet computers, cellular or other wireless phones (e.g., smart phones), notepad computers, mobile stations), wearable devices (e.g., glasses, watches), entertainment devices (e.g., entertainment appliances, set-top boxes communicatively coupled to display devices, game consoles), televisions or other display devices, automotive computers, and the like.

[0184] The processor 1005 may be a single processing unit or multiple processing units, all of which may include a single or multiple computing units or multiple cores. The processor 1005 may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuits, and / or any device that manipulates signals based on operating instructions. Among other capabilities, the processor 1005 may be configured to obtain and execute computer-readable instructions stored in the memory 1007, mass storage device 1006, or other computer-readable media, such as program codes of an operating system 1008, program codes of an application program 1009, program codes of other programs 1010, and the like.

[0185] The memory 1007 and the mass storage device 1006 are examples of computer-readable storage media for storing instructions, which are executed by the processor 1005 to implement the various functions described above. For example, the memory 1007 may generally include both volatile memory and non-volatile memory (e.g., RAM, ROM, etc.). In addition, the mass storage device 1006 may generally include a hard disk drive, a solid-state drive, a removable medium, including external and removable drives, a memory card, a flash memory, a floppy disk, an optical disk (e.g., CD, DVD), a storage array, a network attached storage, a storage area network, etc. The memory 1007 and the mass storage device 1006 may all be collectively referred to herein as memory or computer-readable storage media, and may be a non-transitory medium capable of storing computer-readable, processor-executable program instructions as computer program code, which may be executed by the processor 1005 as a specific machine configured to implement the operations and functions described in the examples herein.

[0186] A plurality of programs may be stored on the mass storage device 1006. These programs include an operating system 1008, one or more application programs 1009, other programs 1010, and program data 1011, and they may be loaded into the memory 1007 for execution. Examples of such application programs or program modules may include, for example, computer program logic (e.g., computer program code or instructions) for implementing the following components / functions: the test apparatus 200 (including the first temperature acquisition module 210, the second temperature acquisition module 220, and the adjustment module 230) and the test method of the battery (including any suitable steps of the temperature control method), and / or other embodiments described herein.

[0187] Although in Fig.14 1000 , but operating system 1008 , application programs 1009 , other programs 1010 , and program data 1011 , or portions thereof, may be implemented using any form of computer-readable media accessible by computing device 1000 .

[0188] One or more communication interfaces 1002 are used to exchange data with other devices, such as through a network, direct connection, etc. Such communication interfaces can be one or more of the following: any type of network interface (e.g., a network interface card (NIC)), a wired or wireless (such as IEEE802.11 wireless LAN (WLAN)) wireless interface, a Worldwide Interoperability for Microwave Access (Wi-MAX) interface, an Ethernet interface, a Universal Serial Bus (USB) interface, a cellular network interface, a Bluetooth™ interface, a Near Field Communication (NFC) interface, etc. The communication interface 1002 can facilitate communication within a variety of network and protocol types, including wired networks (e.g., LAN, cable, etc.) and wireless networks (e.g., WLAN, cellular, satellite, etc.), the Internet, etc. The communication interface 1002 can also provide communication with an external storage device (not shown) such as a storage array, a network attached storage, a storage area network, etc.

[0189] In some examples, a display device 1001 such as a monitor may be included for displaying information and images to a user. Other I / O devices 1003 may be devices that receive various inputs from a user and provide various outputs to the user, and may include a touch input device, a gesture input device, a camera, a keyboard, a remote control, a mouse, a printer, an audio input / output device, and the like.

[0190] The technology described herein can be supported by these various configurations of the computing device 1000, and is not limited to the specific examples of the technology described herein. For example, the functionality can also be implemented in whole or in part on the "cloud" by using a distributed system. The cloud includes and / or represents a platform for resources. The platform abstracts the underlying functionality of the hardware (e.g., server) and software resources of the cloud. Resources may include applications and / or data that can be used when performing computing processing on a server away from the computing device 1000. Resources may also include services provided over the Internet and / or through a subscriber network such as a cellular or Wi-Fi network. The platform can abstract resources and functions to connect the computing device 1000 to other computing devices 1000. Therefore, the implementation of the functions described herein can be distributed throughout the cloud. For example, the functions can be implemented partially on the computing device 1000 and partially through a platform that abstracts the functions of the cloud.

[0191] An embodiment of the present application provides a computer-readable storage medium storing instructions, which, when executed individually or collectively by one or more processors of a computing device, enable the computing device to execute the method in the above embodiment.

[0192] Computer-readable storage media include volatile and nonvolatile, removable and non-removable media implemented by any method or technology for storage of information, such as computer-readable instructions, data structures, program modules, or other data. Computer-readable storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD), or other optical storage devices, magnetic cassettes, magnetic tapes, magnetic disk storage devices or other magnetic storage devices, or any other non-transmission media that can be used to store information for access by computing device 1000.

[0193] An embodiment of the present application provides a computer program product, which includes instructions. When the instructions are executed individually or collectively by one or more processors of a computing device, the computing device executes the method in the above embodiment.

[0194] An embodiment of the present application provides a method for testing a battery, wherein a motor assembly of the battery is placed in a test chamber with circulating fluid for testing.

[0195] Temperature control methods include: Step 110, obtaining the maximum value of the temperature difference between each pair of sub-regions on the surface of the battery cell as a first temperature difference; Step 120, obtaining a second temperature difference between the actual temperature of the circulating fluid and the set temperature; Step 130: When either the first temperature difference or the second temperature difference is greater than a preset value, the larger of the first temperature difference and the second temperature difference is used as a temperature deviation value, and based on the temperature deviation value, the temperature of the circulating fluid is adjusted by a first feedback control algorithm, and / or the flow rate of the circulating fluid is adjusted by a second feedback control algorithm. The first feedback control algorithm and the second feedback control algorithm may both be PID closed-loop control algorithms.

[0196] The temperature adjustment is performed N times so that the obtained first temperature difference and the second temperature difference are both smaller than a preset value, and N is an integer greater than or equal to 1.

[0197] Based on the temperature deviation value, adjusting the temperature of the circulating fluid by a first feedback control algorithm includes: Based on the temperature deviation value, determining a target temperature of the circulating fluid; The temperature of the circulating fluid is adjusted by a first feedback control algorithm based on the target temperature and the actual temperature of the circulating fluid.

[0198] When the first temperature difference is used as the temperature deviation value, determining the target temperature of the circulating fluid based on the temperature deviation value may include: Get the current temperature of the circulating fluid, and use the sum of the current temperature and the temperature deviation as the target temperature.

[0199] Alternatively, based on the fact that the larger of the temperatures of the two sub-areas forming the first temperature difference is greater than the set temperature, the difference between the current temperature and the temperature deviation value may be used as the target temperature; based on the fact that the larger of the temperatures of the two sub-areas forming the first temperature difference is less than the set temperature, the sum of the current temperature and the temperature deviation value may be used as the target temperature.

[0200] When the second temperature difference is used as the temperature deviation value, determining the target temperature of the circulating fluid based on the temperature deviation value may include: using the set temperature as the target temperature.

[0201] Based on the temperature deviation value, adjusting the flow rate of the circulating fluid by the second feedback control algorithm includes: Determining a first change value of the flow rate of the circulating fluid according to the temperature deviation value and the first mapping relationship; Acquire a first current flow rate of the circulating fluid, and acquire a first target flow rate based on the first current flow rate and the first change value; Based on the deviation between the first target flow rate and the actual flow rate of the circulating fluid, the temperature of the circulating fluid is adjusted by a second feedback control algorithm.

[0202] When the first temperature difference is used as the temperature deviation value, obtaining the first target flow rate based on the first current flow rate and the first change value may include: taking the sum of the first current flow rate and the first change value as the first target flow rate.

[0203] When the second temperature difference is used as the temperature deviation value, obtaining the first target flow rate based on the first current flow rate and the first change value may include: based on the actual temperature of the circulating fluid being less than the set temperature, taking the result of subtracting the first change value from the first current flow rate of the circulating fluid as the first target flow rate; based on the actual temperature of the circulating fluid being greater than the set temperature, taking the result of adding the first change value to the first current flow rate of the circulating fluid as the first target flow rate.

[0204] like Fig. 9 As shown, based on the temperature deviation value, adjusting the temperature of the circulating fluid by a first feedback control algorithm, and adjusting the flow rate of the circulating fluid by a second feedback control algorithm include: Step 1327, determining a target temperature of the circulating fluid based on the temperature deviation value; Step 1328, obtaining a first output value of a first feedback control algorithm based on a deviation value between a target temperature of the circulating fluid and an actual temperature of the circulating fluid; Step 1329, adjusting the temperature of the circulating fluid based on the first output value; Step 1330, determining a second target flow rate of the circulating fluid based on the first output value; Step 1331, based on the second target flow rate and the actual flow rate of the circulating fluid, the flow rate of the circulating fluid is adjusted by a second feedback control algorithm.

[0205] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery testing method, characterized in that: include: Acquire the maximum value of the temperature difference between each pair of sub-regions on the surface of the battery cell as a first temperature difference, wherein each of the sub-regions is a different region on the surface of the battery cell; Obtaining a second temperature difference between an actual temperature of a circulating fluid and a set temperature, wherein the battery cell is placed in the circulating fluid for testing; When either the first temperature difference or the second temperature difference is greater than a preset value, the temperature of the circulating fluid is adjusted, and / or the flow rate of the circulating fluid is adjusted; wherein, All the above steps are recorded as one temperature adjustment, and the temperature adjustment is performed N times so that the temperature difference between each sub-area and the temperature difference between the actual temperature of the circulating fluid and the set temperature are both less than the preset value, and N is an integer greater than or equal to 1.

2. The battery testing method according to claim 1, characterized in that: When either the first temperature difference or the second temperature difference is greater than a preset value, adjusting the temperature of the circulating fluid and / or the flow rate of the circulating fluid comprises: When either the first temperature difference or the second temperature difference is greater than a preset value, the larger one of the first temperature difference and the second temperature difference is used as a temperature deviation value; Based on the temperature deviation value, the temperature of the circulating fluid is adjusted by a first feedback control algorithm, and / or the flow rate of the circulating fluid is adjusted by a second feedback control algorithm.

3. The battery testing method according to claim 2, characterized in that: Based on the temperature deviation value, adjusting the temperature of the circulating fluid by the first feedback control algorithm includes: determining a target temperature of the circulating fluid based on the temperature deviation value; The temperature of the circulating fluid is adjusted by the first feedback control algorithm based on the target temperature and the actual temperature of the circulating fluid.

4. The battery testing method according to claim 3, characterized in that: The first temperature difference is used as the temperature deviation value, and the determining the target temperature of the circulating fluid based on the temperature deviation value includes: Acquire the current temperature of the circulating fluid, where the current temperature is the actual temperature of the circulating fluid at the moment when the temperature deviation value is acquired; Acquire the target temperature based on the current temperature and the temperature deviation value; The second temperature difference is used as the temperature deviation value, and the determining the target temperature of the circulating fluid based on the temperature deviation value includes: The set temperature is set as the target temperature.

5. The battery testing method according to claim 4, characterized in that: The acquiring the target temperature based on the current temperature and the temperature deviation value comprises: The sum of the current temperature and the temperature deviation value is used as the target temperature.

6. The battery testing method according to claim 4, characterized in that: The acquiring the target temperature based on the current temperature and the temperature deviation value comprises: When the larger of the temperatures of the two sub-areas forming the first temperature difference is greater than the set temperature, taking the difference between the current temperature and the temperature deviation value as the target temperature; When the larger one of the temperatures of the two sub-areas forming the first temperature difference is lower than the set temperature, the sum of the current temperature and the temperature deviation value is used as the target temperature.

7. The battery testing method according to claim 2, characterized in that: Based on the temperature deviation value, regulating the flow rate of the circulating fluid by the second feedback control algorithm includes: Determining a first target flow rate of the circulating fluid based on the temperature deviation value; Based on the first target flow rate and the actual flow rate of the circulating fluid, the temperature of the circulating fluid is adjusted by the second feedback control algorithm.

8. The battery testing method according to claim 7, characterized in that: Determining the first target flow rate of the circulating fluid based on the temperature deviation value includes: Acquire a first mapping relationship, where the first mapping relationship is used to characterize the flow rate required to increase or decrease when the temperature of the circulating fluid changes by P degrees, where P is a real number; Determining a first change value of the flow rate of the circulating fluid according to the temperature deviation value and the first mapping relationship; Acquire a first current flow rate of the circulating fluid, where the first current flow rate is an actual flow rate of the circulating fluid at the moment when the temperature deviation value is acquired; The first target flow rate is obtained based on the first current flow rate and the first change value.

9. The battery testing method according to claim 8, characterized in that: The first temperature difference is used as the temperature deviation value, and the determining of the first change value of the flow rate of the circulating fluid according to the temperature deviation value and the first mapping relationship includes: According to the temperature deviation value and the first mapping relationship, determining the flow rate required to increase the temperature of the circulating fluid by the temperature deviation value as the first change value; The acquiring the first target flow rate based on the first current flow rate and the first change value comprises: The sum of the first current flow rate and the first change value is taken as the first target flow rate.

10. The battery testing method according to claim 8, characterized in that: The second temperature difference is used as the temperature deviation value, and the determining the first change value of the flow rate of the circulating fluid according to the temperature deviation value and the first mapping relationship includes: When the actual temperature of the circulating fluid is lower than the set temperature, based on the temperature deviation value and the first mapping relationship, determining a first flow rate that is reduced by the temperature deviation value when the temperature of the circulating fluid increases as the first change value; When the actual temperature of the circulating fluid is greater than the set temperature, based on the temperature deviation value and the first mapping relationship, a second flow rate that increases by reducing the temperature of the circulating fluid by the temperature deviation value is determined as the first change value.

11. The battery testing method according to any one of claims 2 to 10, characterized in that: Based on the temperature deviation value, adjusting the temperature of the circulating fluid by the first feedback control algorithm, and adjusting the flow rate of the circulating fluid by the second feedback control algorithm include: determining a target temperature of the circulating fluid based on the temperature deviation value; acquiring a first output value of the first feedback control algorithm based on a deviation value between the target temperature of the circulating fluid and the actual temperature of the circulating fluid; adjusting the temperature of the circulating fluid based on the first output value; and, determining a second target flow rate of the circulating fluid based on the first output value; Based on the second target flow rate and the actual flow rate of the circulating fluid, the flow rate of the circulating fluid is adjusted by the second feedback control algorithm.

12. The battery testing method according to claim 11, characterized in that: In the case where the first mapping relationship is used to characterize the flow rate required to increase or decrease when the temperature of the circulating fluid changes by P degrees, determining the second target flow rate of the circulating fluid based on the first output value includes: Determining a second change value of the flow rate of the circulating fluid according to the first output value and the first mapping relationship; Acquire a second current flow rate of the circulating fluid, where the second current flow rate is an actual flow rate of the circulating fluid at the moment when the first output value is acquired; The second target flow rate is obtained based on the second current flow rate and the second change value.

13. The battery testing method according to claim 11, characterized in that: The step of adjusting the temperature of the circulating fluid by a first feedback control algorithm based on the temperature deviation value, and / or adjusting the flow rate of the circulating fluid by a second feedback control algorithm only includes one sub-stage. In the sub-stage, based on the temperature deviation value, the temperature of the circulating fluid is adjusted by the first feedback control algorithm, and the flow rate of the circulating fluid is adjusted by the second feedback control algorithm; or, Executing, based on the temperature deviation value, adjusting the temperature of the circulating fluid by using the first feedback control algorithm; or, The flow rate of the circulating fluid is adjusted by the second feedback control algorithm based on the temperature deviation value.

14. The battery testing method according to claim 11, characterized in that: The step of adjusting the temperature of the circulating fluid by a first feedback control algorithm based on the temperature deviation value, and / or adjusting the flow rate of the circulating fluid by a second feedback control algorithm includes two consecutive sub-stages. In one of the sub-stages, the temperature of the circulating fluid is adjusted by the first feedback control algorithm based on the temperature deviation value, or, Executing, based on the temperature deviation value, adjusting the flow rate of the circulating fluid by using the second feedback control algorithm; In another sub-stage, the temperature of the circulating fluid is adjusted by the first feedback control algorithm based on the temperature deviation value, and the flow rate of the circulating fluid is adjusted by the second feedback control algorithm.

15. The battery testing method according to claim 11, characterized in that: The method further comprises: adjusting a calculation coefficient of the first feedback control algorithm in response to an output value of the first feedback control algorithm; and / or, A calculation coefficient of the second feedback control algorithm is adjusted in response to an output value of the second feedback control algorithm.

16. A battery testing device, characterized in that: include: A test chamber, into which circulating fluid is passed, and the test chamber is used to accommodate a battery cell; A first temperature acquisition module, used to acquire the temperature of each sub-region on the surface of the battery cell, each of the sub-regions being a different region on the surface of the battery cell; A second temperature acquisition module, used to acquire a second temperature difference between the actual temperature of the circulating fluid and the set temperature; The regulating module is used to obtain the maximum value of the temperature difference between each of the sub-areas as the first temperature difference based on the temperature of each of the sub-areas, and to regulate the temperature of the circulating fluid and / or the flow rate of the circulating fluid when either the first temperature difference or the second temperature difference is greater than a preset value.

17. The battery testing device according to claim 16, characterized in that: The adjustment module comprises: a first controller, configured to use the larger of the first temperature difference and the second temperature difference as a temperature deviation value when either of the first temperature difference and the second temperature difference is greater than the preset value, and to adjust the temperature of the circulating fluid by a first feedback control algorithm based on the temperature deviation value; The second controller is used to use the larger of the first temperature difference and the second temperature difference as the temperature deviation value when either of the first temperature difference and the second temperature difference is greater than the preset value, and to adjust the flow rate of the circulating fluid through a second feedback control algorithm based on the temperature deviation value.

18. The battery testing device according to claim 16 or 17, characterized in that: The temperature acquisition module comprises: A plurality of temperature acquisition units are disposed in the plurality of sub-areas in a one-to-one correspondence, and are used to acquire the temperature of each of the sub-areas, wherein each temperature acquisition unit is communicatively connected to the adjustment module so that the adjustment module receives the temperature value acquired by the temperature acquisition unit.

19. A computing device, characterized in that include: at least one processor; as well as At least one memory is communicatively connected to the at least one processor, the at least one memory stores instructions, and when the instructions are executed by the at least one processor individually or collectively, the computing device performs the method of any one of claims 1 to 15.

20. A computer-readable storage medium, characterized in that: Instructions are stored, which, when executed individually or collectively by one or more processors of a computing device, cause the computing device to perform the method of any one of claims 1 to 15.

21. A computer program product, characterized in that The method comprises instructions which, when executed individually or collectively by one or more processors of a computing device, cause the computing device to perform the method of any one of claims 1 to 15.

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