Battery SOC regulation and control method, device and equipment, medium and program product

Abstract

The invention provides a battery SOC regulation and control method, device and equipment, a medium and a program product, and belongs to the technical field of batteries. The battery SOC regulation and control method comprises the following steps: acquiring sampling values of working condition parameters of the electric vehicle in a historical use period; determining an initial regulation mileage according to the sampling value of the working condition parameter and a predetermined failure function and expansion force failure threshold; the failure function represents the relationship between the expansive force and the working condition parameters; according to a predetermined first function, a target SOC corresponding to each selected mileage point in a plurality of selected mileage points in a first mileage interval is determined, the first mileage interval is from the initial regulation mileage to the preset maximum safety mileage, and then an SOC regulation strategy is determined; the SOC adjustment strategy enables the SOC upper limit of the battery to be reduced from the initial regulation mileage and not to exceed the corresponding target SOC when the mileage point is selected. The method can delay swelling force aging of the battery, and has a promoting effect on prolonging the safe service life of the battery.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery SOC control method, device, 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 in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in their development.

[0003] As the battery in an electric vehicle ages, the byproducts of the electrochemical reaction inside the battery gradually accumulate, and the battery's expansion force will gradually increase. When the expansion force exceeds the threshold, it may cause the battery structure to fail, affecting the battery's safe service life, and the battery's safe service life directly affects the user's experience. Therefore, how to reasonably delay the aging of the battery's expansion force and extend the battery's safe service life has a vital impact on the development of battery technology. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems existing in the background technology. To this end, one purpose of the present application is to provide a battery SOC control method, device, equipment, medium and program product, wherein the determined SOC adjustment strategy enables the electric vehicle to start reducing the SOC when the mileage reaches the initial control mileage, so as to reasonably delay the aging of the battery expansion force and promote the extension of the safe service life of the battery.

[0005] An embodiment of the first aspect of the present application provides a battery SOC control method, including: Obtaining sampling values ​​of operating parameters of the electric vehicle during the historical use period; the operating parameters are failure influencing factors corresponding to the battery expansion force aging failure mode; The starting control mileage is determined according to the sampling values ​​of the operating condition parameters and the predetermined failure function and expansion force failure threshold; the failure function represents the relationship between the expansion force and the operating condition parameters; According to a predetermined first function, a target SOC corresponding to each selected mileage point in a first mileage interval is determined, and the first mileage interval is from a starting control mileage to a preset maximum safe mileage; wherein the first function represents a relationship between a target SOC corresponding to a certain mileage and an expansion force and an expansion force failure threshold corresponding to a certain mileage; The SOC regulation strategy is determined based on each selected mileage point and its corresponding target SOC; the SOC regulation strategy is executed when the mileage of the electric vehicle reaches the starting regulation mileage, and the SOC regulation strategy is to reduce the SOC upper limit of the battery from the starting regulation mileage and not exceed the corresponding target SOC when the mileage of the electric vehicle reaches the selected mileage point.

[0006] In the technical solution of the embodiment of the present application, the SOC adjustment strategy can be tailored for the battery of the electric vehicle in different usage scenarios. Thanks to the sampling values ​​of the operating condition parameters being collected in the actual operating conditions of the electric vehicle, the SOC adjustment strategy more accurately adapts to the performance of the battery in the actual usage scenario. Therefore, by using the battery SOC control method of the present application, the SOC can be flexibly adjusted according to the driving habits and usage scenarios of the users of the electric vehicle, and the SOC control is optimized to delay the aging process of the battery expansion force, thereby facilitating the safe extension of the battery service life.

[0007] In some embodiments, failure influencing factors include mileage; determining the starting control mileage based on the sampling values ​​of the operating condition parameters and a predetermined failure function and an expansion force failure threshold, including: determining the maximum mileage of the electric vehicle in the second mileage interval that satisfies the expansion force being less than the expansion force failure threshold based on the sampling values ​​of the operating condition parameters and a predetermined failure function; the second mileage interval is the starting mileage to the maximum safe mileage of the electric vehicle in the historical use period; and determining the maximum mileage as the starting control mileage.

[0008] By using the method of this embodiment, before the battery expansion force exceeds the expansion force failure threshold, the expansion force is reduced by adjusting the SOC upper limit, thereby effectively delaying the aging of the battery expansion force and helping to improve the safe service life of the battery.

[0009] In some embodiments, the second mileage interval includes multiple mileage points that gradually increase according to a preset mileage; determining the maximum mileage of the electric vehicle in the second mileage interval that satisfies the expansion force being less than an expansion force failure threshold includes: determining the expansion force corresponding to each of the multiple mileage points based on the sampling value of the operating condition parameter and a predetermined failure function; comparing the expansion force corresponding to each mileage point with the expansion force failure threshold to obtain a comparison result; determining the maximum value of the mileage points whose comparison result is that the expansion force is less than the expansion force failure threshold as the maximum mileage.

[0010] In this embodiment, the expansion force at each mileage point in the second mileage interval is compared with the expansion force failure threshold, so that the starting control mileage determined in this way is more accurate, which in turn helps to make the determined SOC adjustment strategy more accurate.

[0011] In some embodiments, the expansion force corresponding to each mileage point in a plurality of mileage points is determined based on the sampling values ​​of the operating parameters and a predetermined failure function, including: for future mileage points in the second mileage interval, the expansion force corresponding to the future mileage points is determined based on the average value of the sampling values ​​of each failure influencing factor in the operating parameters, the future mileage points and the failure function.

[0012] In this embodiment, the average value of the sampling values ​​of the operating condition parameters is substituted into the failure function to determine the expansion force corresponding to the future mileage points in the second mileage interval, which can effectively smooth the data fluctuations of the sampling values ​​of the operating condition parameters and reduce the influence of interference in the process of collecting the sampling values ​​of the operating condition parameters on the expansion force estimation.

[0013] In some embodiments, the SOC regulation strategy is to linearly reduce the battery's SOC upper limit from the initial regulation mileage. Compared with the technical solution of SOC stepwise change, the SOC regulation strategy obtained by this embodiment allows the battery's state of charge to decrease steadily without obvious mutations, which has a positive effect on delaying the aging of the battery's expansion force.

[0014] In some embodiments, the step of predetermining the failure function includes: determining at least one failure influencing factor corresponding to the expansion force aging failure mode, the at least one failure influencing factor being used to indicate the factor causing the battery expansion force aging; and determining the failure function according to the expansion force and the at least one failure influencing factor. By determining the failure function according to the failure influencing factor under the battery expansion force aging failure mode, the final failure function can be more consistent with the actual expansion force aging process of the battery, accurately simulate the actual state of the battery, and thus obtain a more accurate SOC adjustment strategy, so as to help extend the safe service life of the battery as much as possible.

[0015] In some embodiments, a failure function is determined based on the expansion force and at least one failure influencing factor, including: obtaining an expansion force collection value of the battery; the expansion force collection value indicates a numerical value corresponding to the expansion force of the battery under multiple states; sampling each failure influencing factor of at least one failure influencing factor under multiple states to obtain multiple failure influencing factor collection values, the multiple failure influencing factor collection values ​​indicating the numerical value corresponding to the failure influencing factor of the battery under multiple states; determining the failure function based on the expansion force collection value and the multiple failure influencing factor collection values ​​corresponding to each failure influencing factor of at least one failure influencing factor.

[0016] This embodiment collects the values ​​of the expansion force and the failure influencing factors respectively under multiple states of the expansion force aging failure mode, so that a more accurate failure function can be obtained based on these collected values.

[0017] In some embodiments, the expansion force failure threshold is predetermined as the minimum value among the failure thresholds of the expansion force failure components. In this way, when the expansion force approaches but does not reach the failure threshold of the expansion force failure component in the battery that is most susceptible to deformation under the expansion force, the SOC begins to be reduced, so as to further reduce the risk of battery failure due to expansion force aging.

[0018] In some embodiments, the failure threshold of the expansion force failure component is predetermined based on the mechanical simulation results of the battery, so that the failure threshold of the expansion force failure component can be determined more accurately and efficiently.

[0019] In some embodiments, after determining the SOC adjustment strategy, it also includes: repeating the above steps at intervals of a preset time length. Compared with a fixed SOC adjustment strategy, this embodiment allows the above steps to be repeated at intervals of a preset time length, so that the SOC adjustment strategy is dynamically adjusted according to the sampled values ​​of the updated operating condition parameters at intervals of a preset time length, so that the SOC adjustment strategy can cope with changes in the actual operating conditions of the electric vehicle, and the rationality of the SOC adjustment strategy is improved.

[0020] An embodiment of a second aspect of the present application provides a battery SOC control device, including: an acquisition module, a first determination module, a second determination module, and a third determination module; An acquisition module is used to obtain sample values ​​of operating parameters of the electric vehicle during a historical use period; the operating parameters are failure influencing factors corresponding to the battery expansion force aging failure mode; A first determination module is used to determine the starting control mileage according to the sampled value of the operating condition parameter and a predetermined failure function and an expansion force failure threshold; the failure function represents the relationship between the expansion force and the operating condition parameter; A second determination module is used to determine a target SOC corresponding to each selected mileage point in a first mileage interval according to a predetermined first function, wherein the first mileage interval is from a starting control mileage to a preset maximum safety mileage; wherein the first function represents a relationship between a target SOC corresponding to a certain mileage and an expansion force and an expansion force failure threshold corresponding to a certain mileage; The third determination module is used to determine the SOC adjustment strategy according to each selected mileage point and its corresponding target SOC; the SOC adjustment strategy makes the battery's SOC upper limit decrease from the starting control mileage and does not exceed the corresponding target SOC when the mileage of the electric vehicle reaches the selected mileage point.

[0021] An embodiment of the third aspect of the present application provides a computing device, comprising: at least one processor; and at least one memory communicatively connected to the at least one processor, wherein the at least one memory stores instructions, and when the instructions are executed individually or collectively by the at least one processor, the computing device executes the battery SOC control method in the above-mentioned embodiment.

[0022] 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, enable the computing device to execute the battery SOC control method in the above-mentioned embodiment.

[0023] An embodiment of the fifth aspect of the present application provides a computer program product, including instructions, which, when executed individually or collectively by one or more processors of a computing device, enable the computing device to execute the battery SOC control method in the above embodiment.

[0024] 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

[0025] 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.

[0026] Figure 1 A schematic diagram of a battery SOC control method provided in some embodiments of the present application; Figure 2 A schematic diagram of an SOC regulation strategy for applying the battery SOC regulation method of an embodiment of the present application to different electric vehicles; Figure 3 A schematic diagram showing a comparison of the SOC regulation strategy before and after the SOC regulation strategy of the battery SOC regulation method according to an embodiment of the present application is updated for the same electric vehicle; Figure 4 A schematic diagram of a battery SOC control device according to some embodiments of the present application; Figure 5 A schematic diagram of a computing device for implementing a battery SOC control method provided in some embodiments of the present application. DETAILED DESCRIPTION

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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).

[0033] 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.

[0034] 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 integrated 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; it can be the internal connection of two elements or the interaction relationship between two elements.

[0035] The term "parallel" in this application includes not only the absolutely parallel situation, but also the roughly parallel situation conventionally recognized in engineering; at the same time, "vertical" also includes not only the absolutely vertical situation, but also the roughly vertical situation conventionally recognized in engineering. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0036] Electric vehicles are gradually becoming the mainstream of the global automobile market, especially driven by environmental protection, energy transformation, and technological progress, the popularity of electric vehicles is accelerating.

[0037] As the battery in an electric vehicle ages, the byproducts of the electrochemical reaction inside the battery gradually accumulate, and the battery's expansion force will gradually increase. When the expansion force exceeds the threshold, it may cause the battery structure to fail, affecting the battery's safe service life, and the battery's safe service life directly affects the user's experience. Therefore, how to reasonably delay the aging of the battery's expansion force and extend the battery's safe service life has a vital impact on the development of battery technology.

[0038] At present, most life extension methods are to control the temperature, humidity, pressure, etc. of the environment in which the electric vehicle is located to simulate a certain working condition, test whether the expansion force of the electric vehicle exceeds the threshold when the mileage reaches multiple preset mileages under a certain working condition, and determine the life extension strategy based on the test results. If the expansion force of any of the multiple preset mileages in the test results exceeds the threshold, the life extension strategy includes reducing the upper limit of the state of charge (SOC) during the battery charging process to a certain preset value when the mileage of the electric vehicle to which the battery belongs reaches the preset mileage.

[0039] However, this life extension method has certain limitations, which makes it difficult to maximize the safe service life of the battery. From one perspective, the life extension strategy determined by this life extension method is a fixed strategy, and the needs of electric vehicles of different models vary greatly. It is difficult to meet the differentiated needs of different models by adopting this unified life extension strategy. From another perspective, this life extension method determines the life extension strategy based on a certain operating condition, which cannot fully reflect the complex operating conditions faced by batteries on electric vehicles in actual use.

[0040] In view of this, a battery SOC control method, device, equipment, medium and program product are designed. By obtaining the sampled values ​​of the operating parameters of the electric vehicle during actual operation, the SOC adjustment strategy can be formulated, which can delay the aging of the battery expansion force and extend the safe service life of the battery. Using this method, the SOC adjustment strategy can be tailored for the battery of the electric vehicle under different operating conditions. The SOC adjustment strategy is more flexible and personalized, and can more accurately adapt to actual needs.

[0041] The battery SOC control method provided in the embodiment of the present application is applied to electric vehicles. The execution subject of the battery SOC control method may be, but is not limited to, the controller of the electric vehicle and the battery management system (BMS) of the battery. Exemplarily, the vehicle control unit (VCU) inside the electric vehicle implements the battery SOC control method. The battery involved in the embodiment of the present application may be, but is not limited to, a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc.

[0042] First, the terms involved in the embodiments of the present application are explained: Cycle temperature: refers to the temperature inside the battery during the charge and discharge cycle; Storage temperature: refers to the ambient temperature of the environment in which the battery is stored; Storage time: refers to the cumulative time that the battery is in storage during its service life. For example, the time between the end of battery charging and the next discharge is the storage time.

[0043] Figure 1 The flowchart of the battery SOC control method provided by some embodiments of the present application is schematically shown. Please refer to Figure 1 The present application embodiment provides a battery SOC control method 100, comprising: S110, obtaining sampling values ​​of operating parameters of the electric vehicle in the historical use period. The operating parameters are failure influencing factors corresponding to the battery expansion force aging failure mode.

[0044] S120, determining the starting control mileage according to the sampled values ​​of the operating condition parameters and a predetermined failure function and an expansion force failure threshold. The failure function represents the relationship between the expansion force and the operating condition parameters.

[0045] S130, according to a predetermined first function, determining a target SOC corresponding to each selected mileage point in a first mileage interval, wherein the first mileage interval is from a starting control mileage to a preset maximum safe mileage. The first function represents a relationship between a target SOC corresponding to a certain mileage and an expansion force and an expansion force failure threshold corresponding to a certain mileage.

[0046] S140, determining an SOC adjustment strategy based on each selected mileage point and its corresponding target SOC; the SOC adjustment strategy is executed when the mileage of the electric vehicle reaches the starting control mileage, and the SOC adjustment strategy is to reduce the battery's SOC upper limit from the starting control mileage and not exceed the corresponding target SOC when the mileage of the electric vehicle reaches the selected mileage point.

[0047] In the embodiments of the present application, the electric vehicle may be a pure electric vehicle, a hybrid electric vehicle, or an extended-range vehicle, etc. In the embodiments of the present application, the term "battery" may include a battery cell, or a series, parallel, or hybrid structure of multiple battery cells (e.g., a battery pack or a battery cell group).

[0048] Before S110, the electric vehicle is put into use during the historical use period, during which the values ​​of the operating parameters are collected at preset sampling periods. This embodiment does not specifically limit the preset sampling period, for example, it can be 1s (seconds), 2s, 3s, 5s, 10s, 1min (minute), etc. In S110, the sampled values ​​of the operating parameters collected by the electric vehicle are received.

[0049] The expansion force failure threshold is predetermined as Fmax. The first function is predetermined as SOC x(n) =f [FM(n) , Fmax], where SOC x(n) It refers to the target SOC corresponding to the mileage of n thousand kilometers, F M(n) It refers to the expansion force corresponding to a mileage of n thousand kilometers. The specific process of determining the failure function, the expansion force failure threshold and the first function will be described in detail below. Among them, the maximum safe mileage (hereinafter referred to as Mmax) can select a reasonable value according to user needs, vehicle model, etc. For example, the maximum safe mileage can be 300,000 kilometers in 10 years, 400,000 kilometers in 15 years, etc.

[0050] In S130, the first mileage interval does not include the initial control mileage, and the multiple selected mileage points include the maximum safe mileage. Substituting the selected mileage points into the first function can determine the corresponding target SOC.

[0051] After determining the target SOC corresponding to the selected mileage point, the SOC adjustment strategy is determined in S140. When the mileage of the electric vehicle reaches the starting control mileage, the SOC adjustment strategy is started and the SOC upper limit is reduced according to the SOC adjustment strategy. When the mileage reaches a certain selected mileage point, the SOC upper limit does not exceed the corresponding target SOC. Among them, the state of charge is the ratio of the available power in the battery to the nominal capacity of the battery, which is also called the remaining power.

[0052] The battery SOC control method of this embodiment determines the target SOC corresponding to the selected mileage point based on the sampled values ​​of the operating parameters of the electric vehicle in the historical use period, and then determines the SOC adjustment strategy. The SOC adjustment strategy is started when the mileage of the electric vehicle reaches the starting control mileage, so that the SOC upper limit is reduced. Therefore, the SOC adjustment strategy is not unified and fixed, but is formulated based on the operating parameters in the actual operating conditions of the electric vehicle. In other words, the SOC adjustment strategy can be tailored for the batteries of electric vehicles in different usage scenarios. In this way, the SOC can be adjusted in a personalized manner for the batteries of electric vehicles with different driving habits and driving scenarios. Thanks to the fact that the sampled values ​​of the operating parameters are collected in the actual operating conditions of the electric vehicle, the SOC adjustment strategy more accurately adapts to the performance of the battery in the actual usage scenario (for example, the electric vehicle is driving in an extremely cold area).

[0053] In summary, by utilizing the battery SOC control method of the present application, the SOC can be flexibly adjusted according to the driving habits and usage scenarios of the electric vehicle users, and the SOC control is optimized to delay the battery expansion force aging process, thereby facilitating the safe extension of the battery service life.

[0054] According to some embodiments of the present application, the step of predetermining the failure function includes step 1 and step 2.

[0055] Step 1: determine at least one failure influencing factor corresponding to the expansion force aging failure mode, where the at least one failure influencing factor is used to indicate a factor causing battery expansion force aging.

[0056] Step 2: determining a failure function based on the expansion force and at least one failure influencing factor.

[0057] It can be understood that the failure mechanism of the battery expansion force aging failure mode is that during the storage and charging and discharging process of the battery, the battery realizes charging and discharging through internal chemical reactions. These chemical reactions may be accompanied by some side reactions and the byproducts will gradually increase. Some solid byproducts will accumulate at the battery pole piece, causing the pole piece thickness to gradually increase, causing compression and deformation of the battery structure, and the battery expansion force to gradually increase, causing the battery expansion force to age or even fail. Among them, the amount of byproducts depends on the chemical reaction rate and time. The chemical reaction rate inside the battery is affected by temperature. Since the chemical reaction mainly occurs during storage and charging and discharging, the temperature that affects the chemical reaction rate mainly refers to the cycle temperature (hereinafter referred to as C temp ) and storage temperature (hereinafter referred to as S temp Storage temperature S temp Ambient temperature that can reflect the use environment of electric vehicles, cycle temperature C temp It can be the temperature of any position inside the battery during the charge and discharge process, for example, it can be, but is not limited to, the temperature of the end cap of the battery, the temperature of the battery shell, etc. The amount of by-products is also affected by the storage time (hereinafter referred to as S). time (indicated) and the number of charge and discharge cycles.

[0058] The failure influencing factors may include any factors that may cause the battery expansion force to age. In combination with the above description, it can be seen that in some optional embodiments, the failure influencing factors may include the cycle temperature C temp , Storage temperature S temp , storage time S time In some other optional embodiments, the failure influencing factors may also include the number of charge and discharge cycles, the use time of the electric vehicle, the mileage of the electric vehicle (hereinafter referred to as Cycle), the state of health (SOH) of the battery, etc. Among them, SOH is the percentage of the current capacity of the battery to the capacity when it leaves the factory.

[0059] In this embodiment, the failure function is determined according to the failure influencing factors under the battery expansion force aging failure mode, so that the final failure function can be more consistent with the actual expansion force aging process of the battery, accurately simulate the actual state of the battery, and thus obtain a more accurate SOC adjustment strategy, which is conducive to extending the safe service life of the battery as much as possible.

[0060] According to some embodiments of the present application, the above step 2 may specifically include:

[0061] Sub-step 1: obtaining a battery expansion force collection value. The expansion force collection value indicates a numerical value corresponding to the expansion force of the battery in multiple states.

[0062] Sub-step 2: sampling each failure influencing factor of at least one failure influencing factor under multiple states to obtain multiple failure influencing factor collected values, wherein the multiple failure influencing factor collected values ​​indicate numerical values ​​corresponding to the failure influencing factor of the battery under multiple states.

[0063] Sub-step 3: determining a failure function according to the expansion force collected value and a plurality of failure influencing factor collected values ​​respectively corresponding to each failure influencing factor of at least one failure influencing factor.

[0064] For example, there are multiple failure influencing factors, and the multiple failure influencing factors are respectively cycle temperature C temp , Storage temperature S temp , storage time S time As well as the mileage, each failure influencing factor and the expansion force can be sampled in multiple states to obtain the collected values.

[0065] For example, the mileage collection value is Cycle0 and the cycle temperature collection value is C temp 0. Storage temperature acquisition value is S temp 0. Storage time acquisition value is S time 0, the corresponding expansion force acquisition value F is obtained M(Cycle0) ; The mileage collection value is Cycle0, and the cycle temperature collection value is C temp 0', storage temperature acquisition value is S temp 0', storage time acquisition value is S time 0', the corresponding expansion force acquisition value F is obtained M(Cycle0) '; The mileage collection value is Cycle0, and the cycle temperature collection value is C temp 0'', storage temperature acquisition value is S temp 0'', storage time acquisition value is S time 0'', the corresponding expansion force acquisition value F is obtained M(Cycle0) ''; When the mileage is Cycle 1 and the cycle temperature is C temp 1. Storage temperature is S temp 1. Storage time is S time 1, the corresponding expansion force acquisition value F is obtained M(Cycle1) , and so on.

[0066] F M(Cycle0) =f(Cycle0,Ctemp 0,S temp 0,S time 0); F M(Cycle0) =f(Cycle0,C temp 0', S temp 0', S time 0'); F M(Cycle0) '' = f (Cycle0, C temp 0'', S temp 0'', S time 0''); … F M(Cycle1) =f(Cycle1,C temp 1, S temp 1, S time 1); … Then the final failure function is obtained by fitting the above collected values: Swelling Force = f(Cycle, C temp , S temp , S time ), In the formula, Swelling Force is the expansion force, Cycle is the mileage, and C temp is the cycle temperature, i.e. the internal temperature of the battery during charging and discharging, S temp is the storage temperature of the battery (i.e. the temperature of the environment where the battery is stored), S time For storage time.

[0067] This embodiment collects the values ​​of the expansion force and the failure influencing factors respectively under multiple states of the expansion force aging failure mode, so that a more accurate failure function can be obtained based on these collected values.

[0068] The process in which the first function is predetermined is: in each state, the relationship between the expansion force and the state of charge can also be determined respectively. For the expansion force and the state of charge, sampling can be performed in multiple states to obtain the collected values. The expansion force at different SOCs during the charging process is shown in Table 1.

[0069] Table 1

[0070] According to the data in Table 1, the relationship between the expansion force and the state of charge can be obtained as the second function: Swelling Force = f (SOC), According to the failure function and the second function mentioned above, the third function can be obtained: Swelling Force = f (Cycle, C temp , S temp , S time , SOC).

[0071] Assume that the state of charge at a certain mileage is SOC x(n) , let the expansion force be equal to the expansion force failure threshold Fmax, and substitute it into the third function to get: Fmax=f(Cycle, C temp , S temp , S time , SOC x(n) ), and then SOC can be obtained x(n) .

[0072] It can be understood that when the mileage is n thousand kilometers, the state of charge is SOC max. If SOC max is set to 100%, the corresponding expansion force is F M(n) , F M(n) It refers to the expansion force corresponding to a mileage of n thousand kilometers. x(n) , Fmax), (SOCmax, F M(n) ), from which the first function can be derived: SOC x(n) =f [F M(n) , Fmax].

[0073] It can be understood that in order to prevent the battery expansion force from exceeding Fmax when the vehicle's mileage reaches n million kilometers, the SOC upper limit can be adjusted to SOC x(n) Therefore, in the first function, SOC x(n) That is the target SOC corresponding to a mileage of n thousand kilometers.

[0074] According to some embodiments of the present application, the failure influencing factor may include mileage. The above S120 may specifically include S210 to S220.

[0075] S210, determining the maximum mileage of the electric vehicle in a second mileage interval that satisfies the expansion force being less than the expansion force failure threshold according to the sampled values ​​of the operating condition parameters and a predetermined failure function. The second mileage interval is from the starting mileage to the maximum safe mileage of the electric vehicle in the historical use period.

[0076] S220, determining the maximum mileage as the starting control mileage.

[0077] In S210, the initial mileage of the battery when it is delivered for use, that is, the initial mileage of the electric vehicle when it is put into use, is 00,000 kilometers. The expansion force corresponding to the mileage point in the second mileage interval that is greater than the initial control mileage exceeds the expansion force failure threshold. Therefore, the initial control mileage is the safety critical mileage where the expansion force does not exceed the expansion force failure threshold.

[0078] By using the method of this embodiment, when the mileage of the electric vehicle reaches the initial control mileage, the SOC adjustment strategy is activated, and the expansion force does not exceed the expansion force failure threshold. That is, before the battery expansion force exceeds the expansion force failure threshold, the expansion force is reduced by adjusting the SOC upper limit to effectively delay the battery expansion force aging, which helps to improve the safe service life of the battery.

[0079] In addition, since the initial control mileage is the maximum mileage that satisfies the expansion force being less than the expansion force failure threshold, the SOC is maintained at a higher value before adjusting the SOC, which is beneficial for the electric vehicle to provide sufficient power support during acceleration and fast driving.

[0080] The second mileage interval may specifically include a plurality of mileage points gradually increasing according to the preset mileage. The preset mileage may be designed according to demand and actual working conditions. The preset mileage is a ten thousand kilometers, and the value range of a is 0.5 to 5. For example, a may be selected from any value of 0.5, 1, 2, 3, 4, 5, etc. The specific implementation methods of the above S210 are various.

[0081] According to some embodiments of the present application, the above S210 may specifically include the following steps: S310, determining an expansion force corresponding to each mileage point among a plurality of mileage points according to a sampling value of an operating condition parameter and a predetermined failure function.

[0082] S320, comparing the expansion force corresponding to each mileage point with the expansion force failure threshold to obtain a comparison result.

[0083] S330, determining the maximum value of the mileage points where the comparison result shows that the expansion force is less than the expansion force failure threshold as the maximum mileage.

[0084] In S310 to S330, the expansion force of each mileage point in the second mileage interval is first determined, and the expansion force of each mileage point is compared with the expansion force failure threshold. The multiple mileage points in the second mileage interval may include historical mileage points and future mileage points. The historical mileage points refer to the mileage that has occurred and the electric vehicle has completed in the historical use period, and the future mileage points refer to the mileage that the electric vehicle will reach in the future.

[0085] Taking the sample values ​​of the working condition parameters of the electric vehicle in the historical use period as shown in Table 2 as an example, for the historical mileage points in the second mileage interval, the sample values ​​in Table 2 are substituted into the failure function, and it can be calculated accordingly: F M(M0) = f(M0, C0, S0, T0); F M(M1) = f(M1, C1, S1, T1); F M(M2) = f(M2, C2, S2, T2); F M(M3) = f(M3, C3, S3, T3); F M(M4) =f(M4,C4,S4,T4).

[0086] Table 2

[0087] According to the sampling values ​​of the working condition parameters and the failure function in Table 2, the expansion force at future mileage points in the second mileage interval can also be predicted by calculation. Assume that the comparison results of the expansion force at each mileage point in the second mileage interval and the expansion force failure threshold are as follows: F M(M0) <Fmax,F M(M1) <Fmax,F M(M2) <Fmax,F M(M3) <Fmax, ..., F M(m-a) <Fmax,F M(m) >Fmax,F M(m+a) >Fmax, ..., F M(n) >Fmax, ..., F M(Mmax) >Fmax, the maximum value of the mileage point where the expansion force is less than the expansion force failure threshold is ma ten thousand kilometers, then ma ten thousand kilometers is determined as the starting control mileage.

[0088] In this embodiment, the expansion force at each mileage point in the second mileage interval is compared with the expansion force failure threshold, so that the starting control mileage determined in this way is more accurate, which in turn helps to make the determined SOC adjustment strategy more accurate.

[0089] According to some embodiments of the present application, the above S310 may specifically include the following steps: For future mileage points in the second mileage interval, the expansion force corresponding to the future mileage points is determined according to the average value of the sampled values ​​of each failure influencing factor in the operating condition parameters, the future mileage points and the failure function.

[0090] Taking the sample values ​​of the working condition parameters of the electric vehicle in the historical use period as shown in Table 2 as an example, F M(n) = f(n,C temp , S temp , S time), where M4<n≤Mmax, and substitute (C0+C1+C2+C3+C4) / 5 into C temp , substitute (S0+S1+S2+S3+S4) / 5 into S temp , substitute (T0+T1+T2+T3+T4) / 5 into S time .

[0091] In some optional embodiments, for future mileage points in the second mileage interval, a certain sampled value of the operating condition parameter may be substituted into the failure function to calculate the expansion force corresponding to the future mileage point.

[0092] In contrast, taking the average value of the sampling values ​​of the operating condition parameters and substituting it into the failure function to determine the expansion force corresponding to the future mileage points in the second mileage interval can effectively smooth the data fluctuations of the sampling values ​​of the operating condition parameters, so that the influence of interference in the process of collecting the sampling values ​​of the operating condition parameters on the expansion force estimation is reduced, which is conducive to making the determined SOC regulation strategy more accurate.

[0093] In some optional embodiments, the specific implementation process of S210 may also include the following steps.

[0094] S410, arranging the starting mileage to the maximum safe mileage of the electric vehicle in the historical use period in order from small to large.

[0095] S420, determining the expansion forces of two adjacent mileage points in sequence according to the sampled values ​​of the operating condition parameters and a predetermined failure function.

[0096] S430: Compare the expansion forces of two adjacent mileage points with an expansion force failure threshold.

[0097] S430, in response to the comparison result that the expansion force corresponding to the smaller of the two similar mileage points is less than the expansion force failure threshold, and the expansion force corresponding to the larger one is greater than the expansion force failure threshold, the smaller one is determined as the starting control mileage.

[0098] By adopting the method of this embodiment, there is no need to calculate the expansion force corresponding to all mileage points. The calculation of the expansion force is ended after the starting control mileage is determined. The amount of calculation is small, which is conducive to improving the efficiency of determining the SOC adjustment strategy.

[0099] It is understandable that the determined starting control mileage may be equal to the warranty mileage, or may be less than the warranty mileage, or greater than the warranty mileage, and the warranty mileage is pre-set. In this article, the warranty mileage refers to the maximum mileage promised by the manufacturer or supplier for the electric vehicle or battery during the warranty period. Depending on the battery type and the configuration of the electric vehicle, the warranty mileage is also different, which can be 50,000 kilometers, 100,000 kilometers, etc.

[0100] Figure 2 The schematic diagram schematically shows the SOC regulation strategy of the battery SOC regulation method of the embodiment of the present application applied to different electric vehicles. Figure 2 In the embodiment of the present application, the battery SOC control method is applied to vehicle A, and the initial control mileage is equal to the warranty mileage (shown as M in the figure). EOW ), the SOC adjustment strategy can be specifically to reduce the SOC upper limit when the mileage of vehicle A reaches the warranty mileage, until the mileage of vehicle A reaches M m When the SOC upper limit is reduced to SOC x(m) ; Then continue to reduce the SOC limit until the mileage of vehicle A reaches M n When the SOC upper limit is reduced to SOC x(n) ; Then lower the SOC limit until the mileage of vehicle A reaches M MAX When the SOC upper limit is reduced to SOC x(MAX) The battery SOC control method of the embodiment of the present application is applied to vehicle B, and the initial control mileage is M m If the mileage of vehicle B reaches the initial control mileage, the SOC upper limit will be lowered until the mileage of vehicle A reaches M. n When the SOC upper limit is reduced to SOC x(n) ; Then continue to reduce the SOC limit until the mileage of vehicle A reaches M MAX When the SOC upper limit is reduced to SOC x(MAX) .

[0101] As in the method disclosed in this article, there are various ways to lower the SOC upper limit. It can be lowered at a uniform rate, lowered in stages, or adjusted based on a preset model.

[0102] According to some embodiments of the present application, the above-mentioned SOC regulation strategy can be specifically configured to linearly reduce the SOC upper limit of the battery from the initial regulation mileage, and reduce it to the corresponding target SOC when the mileage of the electric vehicle reaches a selected mileage point.

[0103] by Figure 2 Taking the SOC adjustment strategy of vehicle A as an example, the SOC corresponding to the warranty mileage is initially set, and then the M is calculated. m Corresponding state of charge limit SOC x(m) In this way, the slope between points a and b can be calculated, that is, the rate of decrease of the state of charge, which reflects the decrease of the SOC for every 10,000 kilometers of the electric vehicle. The upper limit of the battery's SOC decreases linearly, that is, the rate of decrease of the battery's state of charge is constant.

[0104] Compared with the technical solution of step-by-step change of SOC, this embodiment enables the SOC to be uniformly reduced when the mileage of the electric vehicle reaches the initial control mileage, and the battery's state of charge is steadily reduced without obvious mutations, so that the battery's expansion force changes smoothly, which has a positive effect on delaying the aging of the battery's expansion force.

[0105] According to some embodiments of the present application, the expansion force failure threshold may be specifically predetermined as a minimum value among the failure thresholds of the expansion force failure components.

[0106] Here, the expansion force failure component refers to a component affected by the expansion force. As the battery is used for a longer time, the battery gradually expands and deforms, generating expansion force, which causes the expansion force failure component to deform or even be damaged and fail.

[0107] Expansion force failure components can be but are not limited to battery pressure strips, integrated busbars (Cells Contact System, CCS), pole pieces, etc. Among them, in the battery pack and battery cell group, there are two end plates arranged opposite to each other and multiple battery cells arranged in a row, and the multiple battery cells are located between the two end plates. The pressure strip extends along the arrangement direction of the multiple battery cells, and the two ends of the pressure strip are respectively connected to the two end plates. During the use of the battery, the battery cells will generate heat and gas, and the two ends of the multiple battery cells will expand and deform, and the pressure strips and integrated busbars will deform accordingly. For example, the failure threshold of the pressure strip is determined to be F1, the failure threshold of the integrated busbar is determined to be F2, and the failure threshold of the pole piece is determined to be F3. The minimum value of F1, F2, and F3 is the expansion force failure threshold. The expansion force failure component with the smallest failure threshold is the first to deform and be damaged under the action of the expansion force.

[0108] By making the minimum value among the failure thresholds of the expansion force failure components as the expansion force failure threshold, the SOC adjustment strategy formulated using the method of the embodiment of the present application begins to reduce the SOC when the expansion force approaches but has not reached the failure threshold of the expansion force failure component in the battery that is most easily deformed under the action of the expansion force, so as to further reduce the risk of battery failure due to expansion force aging.

[0109] According to some embodiments of the present application, the failure threshold of the expansion force failure component can be specifically predetermined based on the mechanical simulation results of the battery. Specifically, a structural model of the battery pack is built, and a mechanical simulation is performed on the structural model of the battery pack, that is, force is applied to the structural model of the battery pack to simulate the expansion force, and the force value at the moment when the expansion force failure component is deformed and fails is tested, and the failure threshold of the expansion force failure component is determined. Then, by comparing the failure thresholds of each expansion force failure component, the minimum value is taken as the expansion force failure threshold Fmax. In this embodiment, the mechanical simulation method is used to more accurately and efficiently determine the failure threshold of the expansion force failure component.

[0110] According to some embodiments of the present application, after the above S140, the battery SOC control method may further include S150.

[0111] S150, repeating the above steps (ie, S110 to S140) at preset time intervals.

[0112] This embodiment does not impose any specific restrictions on the preset duration. For example, the preset duration can be selected from any value of 1 month, 3 months, half a year, etc. The preset duration can be designed specifically according to the usage habits and usage scenarios of the electric vehicle users. For example, if the usage scenario of the electric vehicle is in an extremely cold area, the preset duration can be selected from a smaller value so that the SOC adjustment strategy can be updated more frequently.

[0113] In a specific embodiment, when the electric vehicle is initially put into use, the mileage increases from 00,000 kilometers to 50,000 kilometers, and S110 to S140 are executed once. At this time, the historical use period in S11 is the time period corresponding to the mileage from 00,000 kilometers to 50,000 kilometers. After that, at a preset interval, assuming that the mileage of the electric vehicle increases from 50,000 kilometers to 70,000 kilometers during this period, S110 to S140 are executed again. At this time, the historical use period in S11 is the time period corresponding to the mileage from 50,000 kilometers to 70,000 kilometers.

[0114] Compared with a fixed SOC adjustment strategy, this embodiment allows S110 to S140 to be repeatedly executed at preset time intervals, so that the SOC adjustment strategy is dynamically adjusted at preset time intervals according to the sampled values ​​of the updated operating parameters, so that the SOC adjustment strategy can cope with changes in the actual operating conditions of the electric vehicle, and the rationality of the SOC adjustment strategy is improved, which can greatly delay the aging of the battery expansion force, thereby facilitating the maximization of the safe service life of the battery.

[0115] Figure 3 The schematic diagram schematically shows the comparison of the SOC adjustment strategy before and after the SOC adjustment strategy of the battery SOC control method of the embodiment of the present application is updated for the same electric vehicle. Figure 3 As shown in the figure, the SOC adjustment strategy before the update and the SOC adjustment strategy after the update are similar in that the starting control mileage is equal to the warranty mileage. When the mileage of the electric vehicle reaches the warranty mileage, the SOC upper limit begins to be reduced until the mileage reaches M m When the SOC upper limit is reduced to SOC x(m) The difference is that the updated SOC regulation strategy enables the electric vehicle to have a mileage of M m After that, continue to reduce SOC until the mileage reaches M n When the SOC upper limit is reduced to SOC x(n) ', SOC x(n) '<SOC x(n); Continue to reduce the SOC limit until the mileage reaches M MAX When the SOC upper limit is reduced to SOC x(MAX) ', SOC x(MAX) '<SOC x(MAX) .

[0116] Based on the same technical concept, the embodiment of the present application also provides a battery SOC control device. The embodiment of the battery SOC control device can refer to the embodiment of the battery SOC control method, and the repeated parts will not be repeated. Figure 4 The schematic diagram of the battery SOC control device of some embodiments of the present application is schematically shown, referring to Figure 4 The battery SOC control device 500 includes an acquisition module 510 , a first determination module 520 , a second determination module 530 and a third determination module 540 .

[0117] The acquisition module 510 is used to obtain the sampled values ​​of the operating parameters of the electric vehicle during the historical use period; the operating parameters are the failure influencing factors corresponding to the battery expansion force aging failure mode.

[0118] The first determination module 520 is used to determine the starting control mileage according to the sampled value of the operating condition parameter and the predetermined failure function and expansion force failure threshold. The failure function represents the relationship between the expansion force and the operating condition parameter.

[0119] The second determination module 530 is used to determine the target SOC corresponding to each selected mileage point in a first mileage interval from the initial control mileage to the preset maximum safety mileage according to a predetermined first function, wherein the first function represents the relationship between the target SOC corresponding to a certain mileage and the expansion force and expansion force failure threshold corresponding to a certain mileage.

[0120] The third determination module 540 is used to determine the SOC adjustment strategy according to each selected mileage point and its corresponding target SOC; the SOC adjustment strategy causes the battery's SOC upper limit to decrease from the starting control mileage and not exceed the corresponding target SOC when the mileage of the electric vehicle reaches the selected mileage point.

[0121] The acquisition module 510, the first determination module 520, the second determination module 530 and the third determination module 540 may correspond to S110 to S140 in the battery SOC control method, respectively, and for the sake of brevity, they are not described here. It should be understood that corresponding to the embodiment of the battery SOC control method, the battery SOC control device 500 may also include more modules.

[0122] It should be noted that the functions of the various modules discussed herein can be divided into multiple modules, and / or at least some functions of multiple modules can be combined into a single module. The specific module discussed herein performing an action includes the specific module itself performing the action, or alternatively the specific module calling or otherwise accessing another component or module that performs the action (or performs the action in conjunction with the specific module). Therefore, the specific module that performs an action can include the specific module itself that performs the action and / or another module that the specific module calls or otherwise accesses and performs the action.

[0123] It should also be understood that various techniques may be described herein in the general context of software hardware elements or program modules. Figure 4 The various modules described can be implemented in hardware or in hardware in combination with software and / or firmware. For example, these modules can be implemented as computer program code / instructions, which are configured to be executed in one or more processors and stored in a computer-readable storage medium. Alternatively, these modules can be implemented as hardware logic / circuits. The hardware logic / circuit may include an integrated circuit chip (which includes a processor (e.g., a central processing unit (CPU), a microcontroller, a microprocessor, a digital signal processor (DSP), etc.), a memory, one or more communication interfaces, and / or one or more components in other circuits), and may optionally execute the received program code and / or include embedded firmware to perform functions.

[0124] Figure 5 A schematic diagram of a computing device for implementing a battery SOC control method provided in some embodiments of the present application. Figure 5 As shown, the embodiment of the present application further provides a computing device 600, which may include at least one processor 605 capable of communicating with each other, such as through a bus 604 or other appropriate connections, a memory 607, (multiple) communication interfaces 602, a display device 601, other input / output (I / O) devices 603, and one or more large-capacity storage devices 606. The memory 607 stores instructions, which, when executed by the processor 605, enable the processor 605 to execute the battery SOC control method in the above-mentioned embodiment.

[0125] The processor 605 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 605 may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuits, and / or any computing device that manipulates signals based on operating instructions. Among other capabilities, the processor 605 may be configured to obtain and execute computer-readable instructions stored in the memory 607, mass storage device 606, or other computer-readable media, such as program codes of an operating system 608, program codes of an application program 609, program codes of other programs 610, and the like.

[0126] The memory 607 and the mass storage device 606 are examples of computer-readable storage media for storing instructions that are executed by the processor 605 to implement the various functions described above. For example, the memory 607 may generally include both volatile memory and non-volatile memory (e.g., RAM, ROM, etc.). In addition, the mass storage device 606 may generally include a hard 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., a CD, a DVD), a storage array, a network attached storage, a storage area network, etc. The memory 607 and the mass storage device 606 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 605 as a specific machine configured to implement the operations and functions described in the examples herein.

[0127] A plurality of programs may be stored on the mass storage device 606. These programs include an operating system 608, one or more application programs 609, other programs 610, and program data 611, and they may be loaded into the memory 607 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: a battery SOC control device 500 (including an acquisition module 510, a first determination module 520, a second determination module 530, and a third determination module 540), a battery SOC control method 100 (including any suitable steps of the battery SOC control method 100), and / or other embodiments described herein.

[0128] Although in Figure 5600 , but operating system 608 , application programs 609 , other programs 610 , and program data 611 , or portions thereof, may be implemented using any form of computer-readable media accessible by computing device 600 .

[0129] One or more communication interfaces 602 are used to exchange data with other computing 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 IEEE 802.11 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 TM interface, a Near Field Communication (NFC) interface, etc. The communication interface 602 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 602 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.

[0130] In some examples, a display device 601 such as a monitor may be included for displaying information and images to a user. Other I / O devices 603 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.

[0131] The techniques described herein can be supported by these various configurations of the computing device 600 and are not limited to the specific examples of the techniques 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 can include applications and / or data that can be used when performing computing processing on a server away from the computing device 600. Resources can 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 600 to other computer devices. 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 600 and partially through a platform that abstracts the functions of the cloud.

[0132] An embodiment of the present application also provides a computer-readable storage medium having instructions stored thereon. When the instructions are executed individually or collectively by one or more processors of a computing device, the computing device executes a method as described in any of the above embodiments.

[0133] 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 a computer device.

[0134] An embodiment of the present application also provides a computer program product, including instructions, which, when executed individually or collectively by one or more processors of a computing device, cause the computing device to execute a method as described in any of the above embodiments.

[0135] 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.

[0136] A specific embodiment of the present application is described below. It should be understood that this specific embodiment is described for illustrative purposes only and should not be interpreted as limiting the present application.

[0137] The battery management system has pre-imported a determined failure function and expansion force failure threshold Fmax. The failure function is as follows: Swelling Force = f(Cycle, C temp , S temp , S time ), In the formula, Swelling Force is the expansion force, Cycle is the mileage, and C temp is the cycle temperature, i.e. the internal temperature of the battery during charging and discharging, S temp is the storage temperature of the battery (i.e. the temperature of the environment where the battery is stored), S time For storage time.

[0138] Obtain the sampling values ​​of the vehicle's operating parameters during the historical use period. The operating parameters include the failure influencing factors corresponding to the battery expansion force aging failure mode. The failure influencing factors are the cycle temperature C temp , Storage temperature Stemp , storage time S time , and mileage Cycle.

[0139] According to the sampling value of the operating condition parameter and the predetermined failure function, the expansion force corresponding to each mileage point in the mileage range from the starting mileage of the vehicle in the historical use period to the preset maximum safe mileage Mmax is determined.

[0140] Among them, the initial mileage of the historical use period of the vehicle to which the battery belongs is 00,000 kilometers at the beginning of its use. Based on this, we can get: F M(M0) = f(M0,C temp , S temp , S time ); F M(M1) = f(M1,C temp , S temp , S time ); F M(M2) = f(M2,C temp , S temp , S time ); F M(M3) = f(M3,C temp , S temp , S time ); … F M(m-a) = f(ma,C temp , S temp , S time ); F M(m) = f(m,C temp , S temp , S time ); F M(m+a) = f(m+a,C temp , S temp , S time ); … F M(n) = f(n,C temp , S temp , S time ); … F M(Mmax) = f(Mmax,C temp , S temp , S time ); Where a is a constant greater than 0, m<n, F M(n) Refers to the expansion force corresponding to a mileage of n thousand kilometers.

[0141] Determine whether the expansion force corresponding to each mileage point is less than the expansion force failure threshold; determine the maximum value of the mileage points where the expansion force is less than the expansion force failure threshold as the maximum mileage; and determine the maximum mileage as the starting control mileage.

[0142] For example, F M(M0) <Fmax,F M(M1) <Fmax,F M(M2) <Fmax,F M(M3) <Fmax, ..., F M(m-a) <Fmax,F M(m) >Fmax,F M(m+a) >Fmax, ..., F M(n) >Fmax, ..., F M(Mmax) >Fmax. Therefore, the maximum value of the mileage point where the expansion force is less than the expansion force failure threshold is ma thousand kilometers, so ma thousand kilometers is determined as the starting control mileage.

[0143] According to a predetermined first function, a target SOC corresponding to each selected mileage point in a first mileage interval from the initial control mileage to the preset maximum safety mileage is determined. The first function is as follows: SOC x(n) =f [F M(n) , Fmax] In the formula, SOC x(n) Refers to the target SOC corresponding to a mileage of n thousand kilometers.

[0144] Taking the starting control mileage as ma kilometers as an example, the first mileage interval is (ma, Mmax], and the selected mileage points may include m+a, ..., n, ..., Mmax. Substitute the selected mileage points into the first function to obtain the target SOC corresponding to each selected mileage point, respectively: SOC x(m+a) ,……,SOC x(n) ,……,SOC x(Mmax) .

[0145] According to the selected mileage point and its corresponding target SOC, the SOC adjustment strategy is determined and executed. The SOC adjustment strategy is to make the battery's SOC upper limit not exceed the corresponding target SOC when the vehicle's mileage reaches the selected mileage point.

[0146] Repeat the above steps at preset intervals.

[0147] Among them, the steps for determining the failure function are: Determine at least one failure influencing factor corresponding to the expansion force aging failure mode; at least one failure influencing factor is the number of charge and discharge cycles, the cycle temperature C temp , Storage temperature S temp , storage time S time .

[0148] For the cycle temperature, storage temperature, storage time, mileage and expansion force, sampling can be performed in multiple states to obtain the collected values. In other words, the expansion force under different cycle temperatures, storage temperatures, storage times and mileage can be measured. For example, when the mileage collection value is Cycle0 and the cycle temperature collection value is C temp 0. Storage temperature acquisition value is S temp 0. Storage time acquisition value is S time 0, the corresponding expansion force acquisition value F is obtained M(Cycle0) ; The mileage collection value is Cycle0, and the cycle temperature collection value is C temp 0', storage temperature acquisition value is S temp 0', storage time acquisition value is S time 0', the corresponding expansion force acquisition value F is obtained M(Cycle0) '; The mileage collection value is Cycle0, and the cycle temperature collection value is C temp 0'', storage temperature acquisition value is S temp 0'', storage time acquisition value is S time 0'', the corresponding expansion force acquisition value F is obtained M(Cycle0) ''; When the mileage is Cycle 1 and the cycle temperature is C temp 1. Storage temperature is S temp 1. Storage time is S time 1, the corresponding expansion force acquisition value F is obtained M(Cycle1) , and so on.

[0149] F M(Cycle0) =f(Cycle0,C temp 0,S temp 0,S time 0); F M(Cycle0) =f(Cycle0,C temp 0', S temp 0', S time 0'); F M(Cycle0) '' = f (Cycle0, C temp 0'', S temp 0'', S time 0''); … F M(Cycle1)=f(Cycle1,C temp 1, S temp 1, S time 1); … The final failure function is then fitted based on these collected values.

[0150] In addition, in each state, the relationship between the expansion force and the state of charge can be determined separately. For the expansion force and the state of charge, samples can be taken in multiple states to obtain the collected values. In other words, the expansion force at different SOCs during the charging process can be measured.

[0151] This gives the functional relationship between the expansion force and the state of charge: Swelling Force = f (SOC) According to the failure function and the second function mentioned above, the third function can be obtained: Swelling Force = f (Cycle, C temp , S temp , S time , SOC).

[0152] Assume that the state of charge at a certain mileage is SOC x(n) , let the expansion force be equal to the expansion force failure threshold Fmax, and substitute it into the third function to get: Fmax=f(Cycle, C temp , S temp , S time , SOC x(n) ), and then SOC can be obtained x(n) .

[0153] It can be understood that when the mileage is n thousand kilometers, the state of charge is SOC max. If SOC max is set to 100%, the corresponding expansion force is F M(n) , F M(n) It refers to the expansion force corresponding to a mileage of n thousand kilometers. x(n) , Fmax), (SOCmax, F M(n) ), from which the first function can be derived: SOC x(n) =f [F M(n) , Fmax].

[0154] It can be understood that in order to prevent the battery expansion force from exceeding Fmax when the vehicle's mileage reaches n million kilometers, the SOC upper limit can be adjusted to SOC x(n) Therefore, in the first function, SOC x(n) That is the target SOC corresponding to a mileage of n thousand kilometers.

[0155] The steps for determining the expansion force failure threshold are as follows: building a structural model of the battery pack, performing mechanical simulation on the structural model of the battery pack, and obtaining the failure thresholds F1, F2, F3, ..., F of each expansion force failure component in the battery pack. n The failure thresholds F1, F2, F3, ..., F n For comparison, take F1, F2, F3, ..., F n The minimum value among them is determined as the expansion force failure threshold Fmax.

[0156] 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 SOC control method, characterized in that: include: Obtaining sample values ​​of operating parameters of the electric vehicle during a historical usage period; The operating condition parameters are failure influencing factors corresponding to the battery expansion force aging failure mode; Determining a starting control mileage according to the sampled values ​​of the operating condition parameters and a predetermined failure function and expansion force failure threshold; The failure function represents the relationship between the expansion force and the operating condition parameter; Determine, according to a predetermined first function, a target SOC corresponding to each selected mileage point in a first mileage interval, wherein the first mileage interval is from the initial control mileage to a preset maximum safety mileage; wherein the first function represents a relationship between the target SOC corresponding to a certain mileage, the expansion force corresponding to a certain mileage, and the expansion force failure threshold; According to each selected mileage point and its corresponding target SOC, an SOC regulation strategy is determined; the SOC regulation strategy is to reduce the battery's SOC upper limit from the starting regulation mileage and not exceed the corresponding target SOC when the mileage of the electric vehicle reaches the selected mileage point.

2. The battery SOC control method according to claim 1, characterized in that: The failure influencing factors include mileage; The step of determining the starting control mileage according to the sampled values ​​of the operating condition parameters and the predetermined failure function and expansion force failure threshold comprises: Determine, according to the sampled values ​​of the operating condition parameters and a predetermined failure function, a maximum mileage of the electric vehicle in a second mileage interval in which the expansion force is less than the expansion force failure threshold; the second mileage interval is from the starting mileage of the electric vehicle in the historical use period to the maximum safe mileage; The maximum mileage is determined as the starting control mileage.

3. The battery SOC control method according to claim 2, characterized in that: The second mileage interval includes a plurality of mileage points that gradually increase according to a preset mileage; The step of determining the maximum mileage of the electric vehicle in the second mileage interval that satisfies the expansion force being less than the expansion force failure threshold comprises: Determining an expansion force corresponding to each of the plurality of mileage points according to the sampled value of the operating condition parameter and a predetermined failure function; Comparing the expansion force corresponding to each mileage point with the expansion force failure threshold to obtain a comparison result; The maximum value of the mileage points where the comparison result shows that the expansion force is less than the expansion force failure threshold is determined as the maximum mileage.

4. The battery SOC control method according to claim 3, characterized in that: Determining the expansion force corresponding to each of the plurality of mileage points according to the sampled value of the operating condition parameter and a predetermined failure function includes: For a future mileage point in the second mileage interval, the expansion force corresponding to the future mileage point is determined according to an average value of the sampled values ​​of each failure influencing factor in the operating condition parameter, the future mileage point and the failure function.

5. The battery SOC control method according to claim 1, characterized in that: The SOC regulation strategy is to reduce the SOC upper limit of the battery linearly starting from the starting regulation mileage.

6. The battery SOC control method according to claim 1, characterized in that: The step of predetermining the failure function comprises: Determine at least one failure influencing factor corresponding to the expansion force aging failure mode, wherein the at least one failure influencing factor is used to indicate a factor causing the expansion force aging of the battery; The failure function is determined based on the expansion force and at least one of the failure influencing factors.

7. The battery SOC control method according to claim 6, characterized in that: Determining the failure function according to the expansion force and at least one of the failure influencing factors includes: Acquire an expansion force collection value of the battery; the expansion force collection value indicates a numerical value corresponding to the expansion force of the battery in multiple states; Sampling each failure influencing factor of at least one of the failure influencing factors in the multiple states to obtain a plurality of failure influencing factor acquisition values, wherein the plurality of failure influencing factor acquisition values ​​indicate a numerical value corresponding to the failure influencing factor of the battery in the multiple states; The failure function is determined according to the expansion force collected value and the plurality of failure influencing factor collected values ​​respectively corresponding to each failure influencing factor of at least one of the failure influencing factors.

8. The battery SOC control method according to any one of claims 1 to 7, characterized in that: The expansion force failure threshold is predetermined as a minimum value among the failure thresholds of the expansion force failure members.

9. The battery SOC control method according to claim 8, characterized in that: The failure threshold of the expansion force failure member is predetermined based on mechanical simulation results of the battery.

10. The battery SOC control method according to claim 1, characterized in that: After determining the SOC adjustment strategy, the method further includes: Repeat the above steps at preset intervals.

11. A battery SOC control device, characterized in that: include: An acquisition module, used to acquire sampled values ​​of operating parameters of the electric vehicle during a historical use period; The operating condition parameters are failure influencing factors corresponding to the battery expansion force aging failure mode; A first determination module is used to determine the starting control mileage according to the sampled value of the operating condition parameter and a predetermined failure function and expansion force failure threshold; The failure function represents the relationship between the expansion force and the operating condition parameter; A second determination module is used to determine a target SOC corresponding to each selected mileage point among a plurality of selected mileage points in a first mileage interval according to a predetermined first function, wherein the first mileage interval is from the starting control mileage to a preset maximum safety mileage; wherein the first function represents a relationship between the target SOC corresponding to a certain mileage, the expansion force corresponding to a certain mileage, and the expansion force failure threshold; The third determination module is used to determine the SOC adjustment strategy according to each selected mileage point and its corresponding target SOC; the SOC adjustment strategy enables the SOC upper limit of the battery to decrease from the starting control mileage and not exceed the corresponding target SOC when the mileage of the electric vehicle reaches the selected mileage point.

12. 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, and the at least one memory stores instructions, which, when executed individually or collectively by the at least one processor, enable the computing device to execute the battery SOC control method described in any one of claims 1 to 10.

13. A computer-readable storage medium, characterized in that: Instructions are stored, and when the instructions are executed individually or collectively by one or more processors of a computing device, the computing device is caused to execute the battery SOC control method according to any one of claims 1 to 10.

14. 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, enable the computing device to execute the battery SOC control method according to any one of claims 1 to 10.

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