Method, device, computer equipment and storage medium for correcting battery SOC

Abstract

The present invention provides a method, device, computer device and storage medium for correcting the SOC of a battery. The method includes: obtaining the historical operation record of a reference battery; generating a calendar attenuation rate of the reference battery according to the historical operation record of the reference battery; obtaining the actual usage time of a battery to be corrected; and correcting the SOC of the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar attenuation rate. The technical problem that the existing estimation method for the SOC of a battery is inaccurate due to the aging and attenuation of the battery is solved.

Description

Technical Field

[0001] This application belongs to the field of battery management, and particularly relates to a method, device, computer device, and storage medium for correcting the state of charge (SOC) of a battery. Background Art

[0002] In the field of chemical energy storage, lithium-ion batteries have become the first choice for electrical energy storage due to their excellent characteristics such as environmental friendliness and long cycle life. They are widely used not only in the power generation energy storage supporting of renewable energy sources such as wind power and photovoltaic power, but also in the fields of electric vehicles and distributed household energy storage products. The capacity of a single battery is limited, and a large number of batteries are often connected in series and parallel, making the number of batteries extremely large. When the batteries are used for a certain period of time, they will age, their performance will decay, and their consistency will become poor. Therefore, it is particularly crucial to accurately estimate the state of charge (SOC) of the battery PACK.

[0003] It should be noted that with the aging and decay of the battery, the existing methods for estimating the SOC of the battery are inaccurate. Summary of the Invention

[0004] The present invention provides a method, device, computer device, and storage medium for correcting the SOC of a battery, so as to at least solve the technical problem that the existing methods for estimating the SOC of the battery are inaccurate with the aging and decay of the battery.

[0005] According to the first aspect of the present invention, there is provided a method for correcting the SOC of a battery, the method including: obtaining the historical operation record of a reference battery; generating the calendar decay rate of the reference battery according to the historical operation record of the reference battery; obtaining the actual usage time of the battery to be corrected; and correcting the SOC of the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar decay rate.

[0006] Further, correcting the SOC of the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar decay rate includes: obtaining the displayed SOC of the battery to be corrected; determining the actual decay rate of the battery to be corrected from the calendar decay rate according to the actual usage time of the battery to be corrected; and generating the corrected SOC according to the displayed SOC of the battery to be corrected and the actual decay rate of the battery to be corrected.

[0007] Further, it is characterized in that the historical operation record of the reference battery includes: the initial available discharge capacity of the reference battery and the actual discharge amount of the reference battery in the preset SOC range in the nth week (n≥1), wherein generating the calendar decay rate of the reference battery according to the historical operation record of the reference battery includes: obtaining the discharge depth of the reference battery; generating the calendar decay rate of the reference battery according to the discharge depth of the reference battery, the actual discharge amount of the reference battery in the preset SOC range in the nth week, and the initial available discharge capacity of the reference battery, wherein the calendar decay rate of the reference battery includes the decay rate of the reference battery from the 1st week to the nth week.

[0008] Further, the calendar decay rate of the reference battery is generated according to the following formula: rn = (discharge depth * Co - Cn) / Co, where Co is the initial available discharge capacity of the reference battery, Cn is the actual discharge amount of the reference battery in the preset SOC range in the nth week, and rn is the decay rate of the reference battery in the nth week.

[0009] Further, the preset SOC range is 10% - 90%.

[0010] According to the second aspect of the present invention, there is provided a device for correcting the SOC of a battery, the device includes: a first obtaining unit, configured to obtain the historical operation record of a reference battery; a generating unit, configured to generate the calendar decay rate of the reference battery according to the historical operation record of the reference battery; a second obtaining unit, configured to obtain the actual usage time of the battery to be corrected; and a correcting unit, configured to correct the SOC of the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar decay rate.

[0011] Further, the correcting unit includes: a first obtaining module, configured to obtain the displayed SOC of the battery to be corrected; a determining module, configured to determine the actual decay rate of the battery to be corrected from the calendar decay rate according to the actual usage time of the battery to be corrected; and a correcting module, configured to generate the corrected SOC according to the displayed SOC of the battery to be corrected and the actual decay rate of the battery to be corrected.

[0012] Further, the historical operation record of the reference battery includes: the initial available discharge capacity of the reference battery and the actual discharge amount of the reference battery in a preset SOC range in the nth week (n≥1), wherein the generating unit includes: a second obtaining module, configured to obtain the discharge depth of the reference battery; a generating module, configured to generate a calendar decay rate of the reference battery according to the discharge depth of the reference battery, the actual discharge amount of the reference battery in the preset SOC range in the nth week, and the initial available discharge capacity of the reference battery, wherein the calendar decay rate of the reference battery includes the decay rate of the reference battery from the 1st week to the nth week.

[0013] According to a third aspect of the present invention, there is provided a computer device, which includes the device of any one of the above.

[0014] According to a fourth aspect of the present invention, there is provided a computer-readable storage medium, on which a computer program is stored, and when the computer program is run by a processor, it executes the method of any one of the above.

[0015] The present invention provides a method, device, computer device and storage medium for correcting the SOC of a battery. The method includes: obtaining the historical operation record of a reference battery; generating a calendar decay rate of the reference battery according to the historical operation record of the reference battery; obtaining the actual usage time of a battery to be corrected; and correcting the SOC of the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar decay rate. This solves the technical problem that the existing method for estimating the SOC of a battery is inaccurate as the battery ages and decays. Description of the Drawings

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

[0017] Figure 1 is a flowchart of a method for correcting the SOC of a battery shown according to an exemplary embodiment;

[0018] Figure 2 is a schematic diagram of a device for correcting the SOC of a battery shown according to an exemplary embodiment. Detailed Embodiments

[0019] To enable those skilled in the art to better understand the solution of this application, the following will clearly and completely describe the technical solution in the embodiments of this application in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.

[0020] It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of this application described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0021] Example 1:

[0022] As Figure 1 shown, this application provides a method for correcting the battery SOC, and the method may include:

[0023] Step S11, obtaining the historical operation record of the reference battery.

[0024] Specifically, in this solution, a hardware device with data processing functions such as a server can be used as the execution body of the method of this solution. This solution can first obtain the operation record of the reference battery from the BMS system (battery management system). The type of the above-mentioned reference battery can be the same as that of the battery to be corrected. The above-mentioned historical operation record can be the historical operation record of the entire life cycle of the above-mentioned reference battery. The above-mentioned entire life cycle can be the historical operation parameters from the 1st week to the nth week after the battery is installed.

[0025] Step S13, generating the calendar decay rate of the reference battery according to the historical operation record of the reference battery.

[0026] Specifically, in this solution, the calendar decay rate of the reference battery can be generated according to the entire life cycle of the above-mentioned reference battery. It should be noted that the above-mentioned calendar decay rate can be the different decay rates of the reference battery in different cycle weeks after installation. For example, the decay rate r1 in the first week, the decay rate r2 in the second week, and the decay rate in the nth week is r n .

[0027] Step S15: Obtain the actual usage time of the battery to be corrected.

[0028] Specifically, in this solution, the actual usage time of the battery to be corrected can be obtained. The actual usage time of the battery to be corrected can be the number of weeks after the battery to be corrected is installed.

[0029] Step S17: Perform SOC correction on the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar decay rate.

[0030] It should also be noted here that the battery to be corrected is preferably a lithium iron phosphate battery. Because the existing OCV-SOC static calibration method is only applicable to battery types with a continuously changing battery capacity curve slope, such as ternary lithium batteries and lithium titanate batteries. And in this solution, the SOC of the battery to be corrected is corrected by referring to the historical decay rate of the battery. Especially for battery aging and decay, through this solution, the estimation and calibration of the actual available remaining power can be achieved in the case of battery deterioration and poor battery pack consistency. Therefore, this solution solves the technical problem that the existing SOC estimation method of the battery is inaccurate with the aging and decay of the battery.

[0031] Optionally, step S17 of performing SOC correction on the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar decay rate includes:

[0032] Step S171: Obtain the displayed SOC of the battery to be corrected.

[0033] Step S172: Determine the actual decay rate of the battery to be corrected from the calendar decay rate according to the actual usage time of the battery to be corrected.

[0034] Step S173: Generate the corrected SOC according to the displayed SOC of the battery to be corrected and the actual decay rate of the battery to be corrected.

[0035] Specifically, in this solution, the displayed SOC of the battery to be corrected can be obtained, and then the actual decay rate of the battery to be corrected is determined from the calendar decay rate according to the actual usage time of the battery to be corrected. Optionally, the current actual decay rate of the battery to be corrected can be determined from the above calendar decay rate through the number of cycle weeks after the battery to be corrected is installed. Then, the corrected SOC is generated according to the displayed SOC of the battery to be corrected and the actual decay rate of the battery to be corrected.

[0036] In an alternative embodiment, the above step S173 can be calculated by the following formula:

[0037] SOCn = SOC0(1 - r n );

[0038] Wherein, SOC n is the corrected SOC of the battery to be corrected, SOC0 is the displayed SOC of the battery to be corrected, and r n is the current attenuation rate of the battery to be corrected (i.e., the above-mentioned actual attenuation rate).

[0039] Optionally, the historical operation record of the reference battery includes: the initial discharge available capacity of the reference battery and the actual discharge amount of the reference battery in the preset SOC range in the nth week (n≥1). Among them, step S13 generating the calendar attenuation rate of the reference battery according to the historical operation record of the reference battery includes:

[0040] Step S131, obtaining the discharge depth of the reference battery.

[0041] Step S132, generating the calendar attenuation rate of the reference battery according to the discharge depth of the reference battery, the actual discharge amount of the reference battery in the preset SOC range in the nth week, and the initial discharge available capacity of the reference battery. Among them, the calendar attenuation rate of the reference battery includes the attenuation rate of the reference battery from the 1st week to the nth week.

[0042] Optionally, in the above step S132, the calendar attenuation rate of the reference battery can be generated according to the following formula:

[0043] r n = (discharge depth * C o - C n ) / C o , where C o is the initial discharge available capacity of the reference battery, C n is the actual discharge amount of the reference battery in the preset SOC range in the nth week, and r n is the attenuation rate of the reference battery in the nth week.

[0044] The following combines Table 1 to specifically describe the calculation method of the calendar attenuation rate of the above reference battery:

[0045] Table 1

[0046]

[0047] As shown in Table 1 above, this solution obtains the cumulative discharge amount of the reference battery at 90% and 10% of SOC in each week. The attenuation rate of the reference battery in the first cycle and the nth cycle can be calculated by the following formula:

[0048] r1 = (10.24 - 10.20) / 12.8 = 0.31%;

[0049] r2 = (10.22 - 10.20) / 12.8 = 0.15%;

[0050] r3 = (10.22 - 10.20) / 12.8 = 0.15%;

[0051] r n = (10.22 - 8.85) / 12.8 = 10.70%.

[0052] Optionally, the preset SOC range is 10% - 90%.

[0053] In summary, the present application provides a method for correcting the SOC of a battery based on the attenuation rate of a reference battery, which solves the technical problem that the existing method for estimating the SOC of a battery is inaccurate due to the aging and attenuation of the battery.

[0054] Example 2

[0055] This solution also provides a device for correcting the SOC of a battery, which can be used to execute the method of the first embodiment above. As Figure 2 shown, the device may include:

[0056] A first acquisition unit 20 for acquiring the historical operation record of the reference battery; a generation unit 22 for generating the calendar attenuation rate of the reference battery according to the historical operation record of the reference battery; a second acquisition unit 24 for acquiring the actual usage time of the battery to be corrected; and a correction unit 26 for correcting the SOC of the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar attenuation rate.

[0057] Specifically, this solution can first obtain the operation record of the reference battery from the BMS (Battery Management System). The type of the above reference battery can be the same as that of the battery to be corrected. The above historical operation record can be the historical operation record of the entire life cycle of the reference battery. The above entire life cycle can be the historical operation parameters from the 1st week to the nth week after the battery is installed. This solution can also generate the calendar attenuation rate of the reference battery according to the entire life cycle of the reference battery. It should be noted that the above calendar attenuation rate can be the different attenuation rates of the reference battery in different cycle weeks after installation. For example, the attenuation rate r1 in the first week, the attenuation rate r2 in the second week, and the attenuation rate at the nth week is r n . In this solution, the actual usage time of the battery to be corrected can be obtained. The actual usage time of the above battery to be corrected can be the number of weeks after the battery to be corrected is installed.

[0058] It should also be noted here that the battery to be corrected can preferably be a lithium iron phosphate battery. Because the existing method of OCV-SOC static calibration only applies to battery types with continuously changing slopes of the battery capacity curve, such as ternary lithium batteries and lithium titanate batteries. In this solution, the SOC of the battery to be corrected is corrected by referring to the historical decay rate of the battery. Especially for battery aging and decay, this solution can estimate and calibrate the actually available remaining power in the case of battery deterioration and poor battery pack consistency. Therefore, this solution solves the technical problem that the existing SOC estimation method of the battery is inaccurate with the aging and decay of the battery.

[0059] Optionally, the correction unit includes: a first acquisition module for acquiring the displayed SOC of the battery to be corrected; a determination module for determining the actual decay rate of the battery to be corrected from the calendar decay rate according to the actual usage time of the battery to be corrected; and a correction module for generating a corrected SOC according to the displayed SOC of the battery to be corrected and the actual decay rate of the battery to be corrected.

[0060] Specifically, in this solution, the displayed SOC of the battery to be corrected can be acquired, and then the actual decay rate of the battery to be corrected is determined from the calendar decay rate according to the actual usage time of the battery to be corrected. Optionally, the current actual decay rate of the battery to be corrected can be determined from the above calendar decay rate through the number of charge-discharge cycles after the battery to be corrected is installed. Then, a corrected SOC is generated according to the displayed SOC of the battery to be corrected and the actual decay rate of the battery to be corrected.

[0061] Optionally, the historical operation record of the reference battery includes: the initial available discharge capacity of the reference battery and the actual discharge amount of the reference battery in the preset SOC interval in the nth week (n≥1). Among them, the generation unit includes: a second acquisition module for acquiring the depth of discharge of the reference battery; and a generation module for generating the calendar decay rate of the reference battery according to the depth of discharge of the reference battery, the actual discharge amount of the reference battery in the preset SOC interval in the nth week, and the initial available discharge capacity of the reference battery. The calendar decay rate of the reference battery includes the decay rate of the reference battery from the 1st week to the nth week.

[0062] This application also provides a computer device, which includes the device according to any one of the second embodiments.

[0063] This application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is run by a processor, it executes the method according to any one of the first embodiments.

[0064] It can be understood that the same or similar parts in the above embodiments can be referred to each other, and for the content not detailed in some embodiments, reference can be made to the same or similar content in other embodiments.

[0065] It should be noted that in the description of the present application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present application, unless otherwise specified, the meaning of "a plurality of" or "many" refers to at least two.

[0066] It should be understood that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may be an intermediate element at the same time; when an element is referred to as "connected to" another element, it can be directly connected to the other element or there may be an intermediate element at the same time. In addition, the "connection" used here can include wireless connection; the phrase "and / or" includes any unit and all combinations of one or more of the associated listed items.

[0067] Any process or method description shown in the flowchart or described in other ways herein can be understood as: representing a module, segment, or part of code including one or more executable instructions for implementing a specific logical function or process, and the scope of the preferred embodiments of the present application includes additional implementations, where the functions can be executed in a manner that is not shown or discussed in order, including in a substantially simultaneous manner or in a reverse order according to the involved functions, which should be understood by those skilled in the technical field of the embodiments of the present application.

[0068] It should be understood that each part of the present application can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following well-known technologies in the art can be used: discrete logic circuits with logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits with appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0069] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the methods of the above embodiments can be completed by instructing relevant hardware through a program, and the above program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0070] In addition, each functional unit in various embodiments of the present application may be integrated into a processing module, or each unit may exist physically alone, or two or more units may be integrated into one module. The above integrated module may be implemented in the form of hardware or in the form of a software functional module. If the above integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0071] The above-mentioned storage medium may be a read-only memory, a magnetic disk, an optical disc, or the like.

[0072] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0073] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A method for correcting the SOC of a battery, characterized in that, The method includes: Obtaining the historical operation record of the reference battery; Generating the calendar attenuation rate of the reference battery according to the historical operation record of the reference battery; Obtaining the actual usage time of the battery to be corrected; Performing SOC correction on the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar attenuation rate; The historical operation record of the reference battery includes: the initial discharge available capacity of the reference battery and the actual discharge amount of the reference battery in the preset SOC interval in the nth week (n≥1), wherein generating the calendar attenuation rate of the reference battery according to the historical operation record of the reference battery includes: Obtaining the discharge depth of the reference battery; Generating the calendar attenuation rate of the reference battery according to the discharge depth of the reference battery, the actual discharge amount of the reference battery in the preset SOC interval in the nth week, and the initial discharge available capacity of the reference battery, wherein the calendar attenuation rate of the reference battery includes the attenuation rate of the reference battery from the 1st week to the nth week; Generating the calendar attenuation rate of the reference battery according to the following formula: r n = (Depth of discharge * C o - C n ) / C o , where C o is the initial available discharge capacity of the reference battery, C n is the actual discharge amount of the reference battery in the preset SOC range in the nth week, and r n is the attenuation rate of the reference battery in the nth week.

2. The method according to claim 1, wherein Performing SOC correction on the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar attenuation rate includes: Obtaining the displayed SOC of the battery to be corrected; Determining the actual attenuation rate of the battery to be corrected from the calendar attenuation rate according to the actual usage time of the battery to be corrected; Generating the corrected SOC according to the displayed SOC of the battery to be corrected and the actual attenuation rate of the battery to be corrected.

3. The method according to claim 1, wherein The preset SOC interval is 10%-90%.

4. A correction device for battery SOC, characterized in that, The device includes: A first acquisition unit for obtaining the historical operation record of the reference battery; A generation unit for generating the calendar attenuation rate of the reference battery according to the historical operation record of the reference battery; A second acquisition unit for obtaining the actual usage time of the battery to be corrected; A correction unit for performing SOC correction on the battery to be corrected according to the actual usage time of the battery to be corrected and the calendar attenuation rate; The historical operation record of the reference battery includes: the initial discharge available capacity of the reference battery and the actual discharge amount of the reference battery in the preset SOC interval in the nth week (n≥1), wherein the generation unit includes: A second acquisition module for obtaining the discharge depth of the reference battery; A generation module, configured to generate a calendar decay rate of the reference battery according to the depth of discharge of the reference battery, the actual discharge amount of the reference battery in a preset SOC range in the nth week, and the initial available discharge capacity of the reference battery, where the calendar decay rate of the reference battery includes the decay rates of the reference battery from the 1st week to the nth week; generating the calendar decay rate of the reference battery according to the following formula: r n =(Depth of discharge * C o - C n ) / C o , where C o is the initial available discharge capacity of the reference battery, C n is the actual discharge amount of the reference battery in the preset SOC range in the nth week, and r n is the decay rate of the reference battery in the nth week.

5. The device according to claim 4, characterized in that, The correction unit includes: A first acquisition module for obtaining the displayed SOC of the battery to be corrected; A determination module for determining the actual attenuation rate of the battery to be corrected from the calendar attenuation rate according to the actual usage time of the battery to be corrected; A correction module for generating the corrected SOC according to the displayed SOC of the battery to be corrected and the actual attenuation rate of the battery to be corrected.

6. A computer device, characterized in that, The computer device includes the device according to any one of claims 4 to 5.

7. A computer-readable storage medium, characterized in that, A computer program is stored on the computer-readable storage medium, and when the computer program is run by a processor, it executes the method according to any one of claims 1 to 3.

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