SOC (State of Charge) estimation method and device of battery pack and electronic equipment

Abstract

The invention discloses an SOC estimation method and device for a battery pack and electronic equipment, and has the beneficial effects that the SOC of the battery pack is obtained based on a first SOC data set, and the calculation is simple and efficient; the first SOC data of the single batteries are screened through the threshold range, the single batteries meeting the threshold range and the SOC of the single batteries are found out, and the influence of the abnormal SOC is avoided; the threshold range is combined with the SOC of the single battery at the historical moment, so that the error caused by electric sudden change of the result is avoided, and the result is more accurate; obtaining an SOC estimation value based on the second SOC data set and an SOC estimation model; the SOC estimation model combines the second SOC data and the weight of the single battery, considers the contribution degree of the single battery in the battery pack, optimizes the estimation result, and improves the accuracy; the group SOC and the SOC estimation value are fused to generate a final SOC; the fusion model considers the importance degree of two times of data, the result is more accurate, and the accuracy is improved.

Description

Technical Field

[0001] The present invention belongs to the field of batteries, and in particular relates to a method and device for estimating the SOC of a battery pack, and electronic equipment. Background Art

[0002] With the rapid development of new energy technologies, energy storage systems are increasingly being used in power systems. SOC estimation of energy storage systems is one of the key technologies in battery management systems (BMS). Accurate SOC estimation can effectively improve battery efficiency, extend battery life, and ensure safe operation of the system.

[0003] At present, for the estimation of the state of charge (SOC) in conventional batteries, domestic and foreign scholars have proposed some methods, such as the ampere-hour integration method, the Kalman filter method, the adaptive Kalman filter method, etc. However, on the one hand, these methods usually still have some shortcomings. For example, the ampere-hour integration method is simple and easy to implement, but the cumulative error caused by factors such as current sampling gradually increases, resulting in an increase in the error of SOC estimation, which cannot meet the requirements of long-term use in actual engineering; the Kalman filter method is widely used because of its small calculation amount and easy implementation; the adaptive Kalman filter algorithm often does not consider the temperature factor and the charge and discharge rate factor. The reason is that under ideal laboratory conditions, these two factors do not change much, but in actual engineering applications, such as the energy feedback process of electric vehicles, the temperature and charge and discharge rate will have a great impact on the accuracy of battery SOC estimation. On the other hand, these methods are usually applicable to conventional batteries (or battery packs) and are not applicable to hybrid energy storage devices. In addition, the methods used in the prior art to estimate the state of charge (SOC) in hybrid energy storage devices have large errors. In actual use, they usually have low accuracy and do not meet actual needs.

[0004] Therefore, developing a SOC estimation method with high accuracy and strong applicability is a technical problem to be solved. Summary of the invention

[0005] Based on this, it is necessary to provide a method, device and electronic device for estimating the SOC of a battery pack in response to the problems of the prior art.

[0006] In a first aspect, an embodiment of the present application provides a method for estimating the SOC of a battery pack, comprising the following steps: S1: Obtaining the operating parameters of the battery pack at the current moment and the initial parameters at the initial moment; S2: based on the operating parameters, the initial parameters and the ampere-hour integration method, obtaining first SOC data of multiple battery cells of the battery pack at the current moment, wherein the multiple first SOC data constitute a first SOC data set; S3: based on the first SOC data set, obtaining the battery pack SOC at the current moment; S4: Determine whether each of the first SOC data in the first SOC data set meets a preset condition; S4: in response to the first SOC data satisfying a preset condition, the first SOC data satisfying the preset condition is recorded as second SOC data, and all second SOC data constitute a second SOC data set; S5: obtaining an estimated SOC value of the battery pack at the current moment based on the second SOC data set and the SOC estimation model; S6: The estimated SOC value at the current moment and the group SOC are combined and calculated to obtain the final SOC value of the battery pack at the current moment; Among them, the SOC estimation model is expressed by the following formula: (1); Among them, the final SOC value of the battery pack at the current moment is expressed by the following formula: (2); in, is the estimated SOC value, is the total number of data in the second SOC data set, The second SOC data set is Second SOC data, For the The weight of the second SOC data, satisfy ; is the final SOC value, For group SOC, is the fusion coefficient, .

[0007] Preferably, the first SOC data is expressed by the following formula: (3); in, is the total number of battery cells in the battery pack, For the The first SOC data of each battery cell, For the The SOC of each battery cell at the initial moment, is the initial moment, For the current moment, is the available capacity of the battery, is the Coulomb efficiency.

[0008] Preferably, the preset condition is expressed by the following formula: (4); in, is the minimum SOC threshold, is the maximum SOC threshold.

[0009] Preferably, the minimum SOC threshold and maximum SOC threshold Obtained through: Acquire third SOC data of multiple battery cells of the battery pack at each time point at multiple time points before the current time point, and obtain multiple third SOC data sets corresponding to the multiple time points; Obtaining an average SOC, a minimum SOC, and a maximum SOC of all battery cells based on a plurality of third SOC data sets; Based on the average SOC, minimum SOC, maximum SOC and threshold calculation model, the minimum SOC threshold is obtained. and maximum SOC threshold .

[0010] Preferably, the threshold calculation model is expressed by the following formula: (5); (6); in, is the average SOC of all battery cells, is the minimum SOC of all battery cells, is the maximum SOC of all battery cells.

[0011] Preferably, It is expressed by the following formula: (7); in, To obtain the total number of times of the third SOC data, For the The average SOC of multiple battery cells at a certain moment is expressed by the following formula: (8); in, For the Moment The SOC of a single battery.

[0012] Preferably, It is expressed by the following formula: (9); in, For the The minimum SOC of multiple battery cells at a certain moment is expressed by the following formula: (10).

[0013] Preferably, It is expressed by the following formula: (11); in, For the The maximum SOC of multiple battery cells at a certain moment is expressed by the following formula: (12).

[0014] In a second aspect, an embodiment of the present application provides a SOC estimation device for a battery pack, comprising: A data acquisition unit, used to acquire the operating parameters of the battery pack at the current moment and the initial parameters at the initial moment; a data processing unit, configured to obtain first SOC data of a plurality of battery cells of a battery pack at a current moment based on the operating parameter, the initial parameter and the ampere-hour integration method, wherein the plurality of first SOC data constitute a first SOC data set; a condition judgment unit, configured to judge whether each of the first SOC data in the first SOC data set meets a preset condition; a condition response unit, configured to, in response to the first SOC data satisfying a preset condition, record the first SOC data satisfying the preset condition as second SOC data, and all second SOC data constitute a second SOC data set; A data generating unit, configured to obtain an estimated SOC value of the battery pack at a current moment based on the second SOC data set and the SOC estimation model; A data fusion unit is used to fuse the current SOC estimation value and the battery pack SOC to obtain the final SOC value of the battery pack at the current moment; Among them, the SOC estimation model is expressed by the following formula: (1); Among them, the final SOC value of the battery pack at the current moment is expressed by the following formula: (2); in, is the estimated SOC value, is the total number of data in the second SOC data set, The second SOC data set is Second SOC data, For the The weight of the second SOC data, satisfy ; is the final SOC value, For group SOC, is the fusion coefficient, .

[0015] In a third aspect, an embodiment of the present application provides an electronic device, the electronic device comprising: processor; a memory for storing instructions executable by the processor; The processor is used to read the executable instructions from the memory and execute the executable instructions to implement the method described in the first aspect above.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) The first SOC data set of multiple battery cells is obtained by using the ampere-hour integration method, and the group SOC of the battery pack is obtained based on the first SOC data set. The calculation is simple, efficient and has high accuracy. (2) The first SOC data of the battery cell at the current moment is screened through a preset threshold range, and the SOC data of all battery cells that meet the preset threshold range are found to form a second SOC data set, thereby preventing abnormal SOC beyond the threshold range from affecting the accuracy of the result; at the same time, the setting of the preset threshold range combines the SOC data of battery cells at multiple historical moments, thereby avoiding the error caused by the sudden change of battery cells at a single moment, making the result more accurate, and the method is simple and efficient; (3) Based on the second SOC data set and the SOC estimation model, an SOC estimation value of the battery pack is obtained; the SOC estimation model combines the second SOC data of the battery cells that meet the conditions and the weights of the corresponding battery cells, comprehensively considers the contribution of the battery cells in the entire battery pack, further optimizes the SOC estimation result, and improves the calculation accuracy; (4) The two data obtained above: group SOC and SOC estimation value, are fused through the fusion model to generate the final SOC estimation value; the fusion model takes into account the importance of the two data and sets the fusion coefficient in a specific range, making the result more precise and further improving the accuracy of the result.

[0017] The SOC estimation method and device of the present application fully consider multiple groups of SOC data of multiple battery cells of a battery pack at historical moments and current moments, avoid abnormal results caused by single data abnormalities, and thus improve the SOC estimation precision and accuracy of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] By referring to the following drawings, the exemplary embodiments of the present invention can be more completely understood. The drawings are used to provide a further understanding of the embodiments of the present application, and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present invention and do not constitute a limitation of the present invention. In the drawings, the same reference numerals generally represent the same parts or steps.

[0019] Figure 1 A flow chart of a method for estimating the SOC of a battery pack provided in an embodiment of the present application; Figure 2 A schematic diagram of a SOC estimation device for a battery pack provided in an embodiment of the present application; Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0020] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0021] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0022] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] Example 1 Reference Figure 1 This embodiment discloses a method for estimating the SOC of a battery pack, comprising the following steps: S1: Obtaining the operating parameters of the battery pack at the current moment and the initial parameters at the initial moment; Specifically, the operating parameters of the battery can be collected through the battery management system. The battery management system is mainly composed of a single cell management layer, a battery pack management layer and a battery group management layer. Among them, the single cell management layer is responsible for collecting single cell information such as battery voltage and temperature, communicating with the outside through CAN (Controller Area Network), and connecting with the outside through a daisy chain; the battery group management layer is responsible for collecting various single cell information uploaded by the single cell management layer, and collecting information such as the battery group voltage, charging and discharging current, etc., while the battery group management layer is responsible for collecting various battery information uploaded by the single cell management layer and the battery group management layer.

[0024] The battery management system can be connected to the battery at one end and to the control and electronic system at the other end, and communicate through the CAN protocol. Ultimately, the battery terminal voltage, excitation current, battery temperature, resistance and other data collected by the battery management system are used as operating parameters.

[0025] The SOC (State of Charge) estimation of the battery system. After the battery system has been used for a period of time or has been unused for a long time, the ratio of the remaining capacity to the capacity in the fully charged state is SOC. The value range of SOC is 0 to 1. When SOC = 0, it means that the battery is fully discharged, and when SOC = 1, it means that the battery is fully charged.

[0026] The embodiment of the present invention obtains the operating parameters of the battery system as a basis for estimating the SOC. The battery state of charge SOC of the battery system at this time can be estimated through the operating parameters of the battery system. In an optional embodiment of the present invention, the operating parameters include at least one of battery voltage, battery current, cycle life, number of cycles, and battery temperature.

[0027] S2: based on the operating parameters, the initial parameters and the ampere-hour integration method, obtaining first SOC data of multiple battery cells of the battery pack at the current moment, wherein the multiple first SOC data constitute a first SOC data set; The ampere-hour integration method is a common method of power accumulation. It estimates the SOC of the battery by accumulating the power of the battery during charging and discharging. The principle of the ampere-hour integration method is to regard the battery as a closed system, measure the energy charged into and discharged from the battery, and record and monitor the battery power for a long time. It can give the remaining power of the battery at any time during operation.

[0028] Specifically, the battery pack of this embodiment includes 16 (i.e. ) battery cells, the first SOC data is expressed by the following formula: (3); in, For the The first SOC data of each battery cell is as follows: , … ; For the The SOC of each battery cell at the initial moment, is the initial moment, For the current moment, is the available capacity of the battery, is the Coulomb efficiency.

[0029] In this embodiment, the ampere-hour integration method is used to obtain the first SOC data set of multiple battery cells, and the group SOC of the battery pack is obtained based on the first SOC data set. The calculation is simple, efficient and accurate.

[0030] S3: based on the first SOC data set, obtaining the battery pack SOC at the current moment; In this embodiment, the battery pack SOC is obtained based on the first SOC data set, which is expressed by the following formula: (13); S4: determining whether each of the first SOC data in the first SOC data set meets a preset condition; Specifically, due to the long-term use of the battery pack, its own performance will vary, so the selection of the threshold is related to the historical SOC obtained during the long-term use of the battery pack. The SOC conditions at different times can be included in the threshold setting process, making the selection of the threshold more practical and more accurate. The safety of the battery pack can be ensured through the setting of the threshold and the judgment of the battery pack, thereby ensuring the accuracy of the calculation results.

[0031] S5: in response to the first SOC data satisfying the preset condition, the first SOC data satisfying the preset condition is recorded as the second SOC data, and all the second SOC data constitute a second SOC data set; Specifically, in this embodiment, the preset conditions are: (4); in, is the minimum SOC threshold, is the maximum SOC threshold.

[0032] Specifically, the minimum SOC threshold and maximum SOC threshold Obtained through: Acquire third SOC data of multiple battery cells of a battery pack at multiple moments before the current moment at each moment, and obtain multiple third SOC data sets corresponding to the multiple moments; Obtaining an average SOC, a minimum SOC, and a maximum SOC of all battery cells based on a plurality of third SOC data sets; Based on the average SOC, minimum SOC, maximum SOC and threshold calculation model, the minimum SOC threshold is obtained. and maximum SOC threshold .

[0033] In this embodiment, the threshold calculation model is expressed by the following formula: (5); (6); in, is the average SOC of all battery cells, is the minimum SOC of all battery cells, is the maximum SOC of all battery cells.

[0034] Specifically, It is expressed by the following formula: (7); in, The total number of moments for obtaining the third SOC data may be set as required, such as 100 moments, 1000 moments, etc., which is not specifically limited in this embodiment; For the The average SOC of multiple battery cells at a certain moment is expressed by the following formula: (8); in, For the Moment The SOC of a single battery.

[0035] In this embodiment, the first SOC data of the battery cells at the current moment are screened through a preset threshold range, and the SOC data of all battery cells that meet the preset threshold range are found to form a second SOC data set, so as to avoid the abnormal SOC exceeding the threshold range from affecting the accuracy of the result; at the same time, the setting of the preset threshold range combines the SOC data of the battery cells at multiple historical moments, which can effectively prevent the error caused by the sudden change of the battery cells when some single cells in the battery pack are overcharged or over-discharged during the charging and discharging process of the battery pack, so that the result is more accurate, and the method is simple and efficient; Specifically, It is expressed by the following formula: (9); in, For the The minimum SOC of multiple battery cells at a certain moment is expressed by the following formula: (10).

[0036] Specifically, It is expressed by the following formula: (11); in, For the The maximum SOC of multiple battery cells at a certain moment is expressed by the following formula: (12).

[0037] After the maximum SOC threshold and the minimum SOC threshold of the battery pack SOC are determined in this embodiment, it can ensure that the SOC of the battery pack is between the maximum SOC threshold and the minimum SOC threshold, and can display the continuity and smoothness of the battery pack SOC without jumps, effectively ensuring that the battery pack will not be over-discharged or over-charged due to SOC evaluation deviation, thereby extending the service life of the battery pack.

[0038] S6: obtaining an estimated SOC value of the battery pack at the current moment based on the second SOC data set and the SOC estimation model; Among them, the SOC estimation model is expressed by the following formula: (1); in, is the estimated SOC value, is the total number of data in the second SOC data set ( ), The second SOC data set is Second SOC data, For the The weight of the second SOC data, satisfy .

[0039] In this embodiment With The target battery pack SOC of each battery cell is related, and can be set as needed in actual work, and is not specifically limited in this embodiment.

[0040] This step obtains the SOC estimation value of the battery pack and the SOC estimation model based on the second SOC data set and the SOC estimation model; the SOC estimation model combines the second SOC data of the battery cells that meet the conditions and the weights of the corresponding battery cells, comprehensively considers the contribution of the battery cells in the entire battery pack, further optimizes the SOC estimation structure, and improves the calculation accuracy.

[0041] S7: The estimated SOC value at the current moment and the group SOC are combined and calculated to obtain the final SOC value of the battery pack at the current moment; Among them, the final SOC value of the battery pack at the current moment is expressed by the following formula: (2); In this embodiment, is the final SOC value, For group SOC, is the fusion coefficient, . The setting is to balance the consideration of the two battery pack SOC values, and can be adjusted as needed in practice.

[0042] In this step, the SOC and SOC estimated values ​​of the two data groups calculated above are fused through a fusion model to generate the final SOC estimated value; the fusion model considers the importance of the two data respectively and sets the fusion coefficient in a specific range to make the result more precise, further improving the accuracy of the structure.

[0043] Compared with the prior art, the present invention has the following beneficial effects: (1) The first SOC data set of multiple battery cells is obtained by using the ampere-hour integration method, and the group SOC of the battery pack is obtained based on the first SOC data set. The calculation is simple, efficient and has high accuracy. (2) The first SOC data of the battery cell at the current moment is screened through a preset threshold range, and the SOC data of all battery cells that meet the preset threshold range are found to form a second SOC data set, thereby preventing abnormal SOC beyond the threshold range from affecting the accuracy of the result; at the same time, the setting of the preset threshold range combines the SOC data of battery cells at multiple historical moments, thereby avoiding the error caused by the sudden change of battery cells at a single moment, making the result more accurate, and the method is simple and efficient; (3) Based on the second SOC data set and the SOC estimation model, an SOC estimation value of the battery pack is obtained; the SOC estimation model combines the second SOC data of the battery cells that meet the conditions and the weights of the corresponding battery cells, comprehensively considers the contribution of the battery cells in the entire battery pack, further optimizes the SOC estimation result, and improves the calculation accuracy; (4) The two data obtained above: group SOC and SOC estimation value, are fused through the fusion model to generate the final SOC estimation value; the fusion model takes into account the importance of the two data and sets the fusion coefficient in a specific range, making the result more precise and further improving the accuracy of the result.

[0044] The SOC estimation method and device of the present application fully consider multiple groups of SOC data of multiple battery cells of a battery pack at historical moments and current moments, avoid abnormal results caused by single data abnormalities, and thus improve the SOC estimation precision and accuracy of the battery pack.

[0045] Example 2 Reference Figure 2 , this embodiment discloses a SOC estimation device for a battery pack, comprising: The data acquisition unit 201 is used to acquire the operating parameters of the battery pack at the current moment and the initial parameters at the initial moment; A data processing unit 202 is used to obtain first SOC data of multiple battery cells of the battery pack at a current moment based on the operating parameters, the initial parameters and the ampere-hour integration method, wherein the multiple first SOC data constitute a first SOC data set; A first data generating unit 203, configured to obtain a battery pack SOC at a current moment based on the first SOC data set; A condition judgment unit 204, configured to judge whether each of the first SOC data in the first SOC data set meets a preset condition; A condition response unit 205, configured to, in response to the first SOC data satisfying a preset condition, record the first SOC data satisfying the preset condition as second SOC data, and all second SOC data constitute a second SOC data set; A second data generating unit 206, configured to obtain an estimated SOC value of the battery pack at a current moment based on the second SOC data set and the SOC estimation model; The data fusion unit 207 is used to fuse the current SOC estimation value and the battery pack SOC to obtain the final SOC value of the battery pack at the current moment; Among them, the SOC estimation model is expressed by the following formula: (1); Among them, the final SOC value of the battery pack at the current moment is expressed by the following formula: (2); in, is the estimated SOC value, is the total number of data in the second SOC data set, The second SOC data set is Second SOC data, For the The weight of the second SOC data, satisfy ; is the final SOC value, For group SOC, is the fusion coefficient, .

[0046] The device provided in the embodiment of the present application can implement the above method, and the system can be implemented by software, hardware, or a combination of software and hardware. For example, the system may include integrated or separate functional modules or units to perform the corresponding steps in the above methods. In some implementations of the embodiments of the present application, the system provided in the embodiment of the present application is based on the same inventive concept as the method provided in the previous embodiment of the present application, and has the same beneficial effect. No further description is given here.

[0047] Example 3 Please refer to Figure 3 , which shows a schematic diagram of an electronic device provided by some embodiments of the present application. Figure 3 As shown, the electronic device 30 includes: a processor 300, a memory 301, a bus 302 and a communication interface 303, and the processor 300, the communication interface 303 and the memory 301 are connected via the bus 302; the memory 301 stores a computer program that can be run on the processor 300, and the processor 300 executes the aforementioned method of the present application when running the computer program.

[0048] The memory 301 may include a high-speed random access memory (RAM), and may also include a non-volatile memory, such as at least one disk memory. The communication connection between the system network element and at least one other network element is realized through at least one communication interface 303 (which may be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. may be used.

[0049] The bus 302 may be an ISA bus, a PCI bus, or an EISA bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. The memory 301 is used to store programs, and the processor 300 executes the programs after receiving execution instructions. The method disclosed in any implementation of the above-mentioned embodiment of the present application may be applied to the processor 300, or implemented by the processor 300.

[0050] The processor 300 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the hardware integrated logic circuit or software instructions in the processor 300. The above processor 300 can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a readily available programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as a hardware decoding processor to be executed, or the hardware and software modules in the decoding processor can be executed. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 301, and the processor 300 reads the information in the memory 301 and completes the steps of the above method in combination with its hardware.

[0051] The electronic device provided in the embodiment of the present application and the method provided in the embodiment of the present application are based on the same inventive concept and have the same beneficial effects as the method adopted, operated or implemented by them.

[0052] It should be noted that the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the systems, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of the boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0053] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0054] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0055] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0056] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0057] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, and other media that can store program codes.

[0058] 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 it. 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. These modifications or replacements do not deviate the essence of the corresponding technical solutions 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.

Claims

1. A method for estimating the SOC of a battery pack, characterized in that: The steps include: S1: Obtaining the operating parameters of the battery pack at the current moment and the initial parameters at the initial moment; S2: based on the operating parameters, the initial parameters and the ampere-hour integration method, obtaining first SOC data of multiple battery cells of the battery pack at the current moment, wherein the multiple first SOC data constitute a first SOC data set; S3: based on the first SOC data set, obtaining the battery pack SOC at the current moment; S4: Determine whether each of the first SOC data in the first SOC data set meets a preset condition; S5: in response to the first SOC data satisfying a preset condition, the first SOC data satisfying the preset condition is recorded as second SOC data, and all second SOC data constitute a second SOC data set; S6: obtaining an estimated SOC value of the battery pack at the current moment based on the second SOC data set and the SOC estimation model; S7: The estimated SOC value at the current moment and the group SOC are combined and calculated to obtain the final SOC value of the battery pack at the current moment; Among them, the SOC estimation model is expressed by the following formula: （1）； Among them, the final SOC value of the battery pack at the current moment is expressed by the following formula: （2）； in, is the estimated SOC value, is the total number of data in the second SOC data set, The second SOC data set is Second SOC data, For the The weight of the second SOC data, satisfy ; is the final SOC value, For group SOC, is the fusion coefficient, .

2. The method according to claim 1, characterized in that The first SOC data is expressed by the following formula: （3）； in, is the total number of battery cells in the battery pack, For the The first SOC data of each battery cell, For the The SOC of each battery cell at the initial moment, is the initial moment, For the current moment, is the available capacity of the battery, is the Coulomb efficiency.

3. The method according to claim 2, characterized in that The preset condition is expressed by the following formula: （4）； in, is the minimum SOC threshold, is the maximum SOC threshold.

4. The method according to claim 3, characterized in that: Minimum SOC threshold and maximum SOC threshold Obtained through: Acquire third SOC data of multiple battery cells of the battery pack at each time point at multiple time points before the current time point, and obtain multiple third SOC data sets corresponding to the multiple time points; Obtaining an average SOC, a minimum SOC, and a maximum SOC of all battery cells based on a plurality of third SOC data sets; Based on the average SOC, minimum SOC, maximum SOC and threshold calculation model, the minimum SOC threshold is obtained. and maximum SOC threshold .

5. The method according to claim 4, characterized in that The threshold calculation model is expressed by the following formula: （5）； （6）； in, is the average SOC of all battery cells, is the minimum SOC of all battery cells, is the maximum SOC of all battery cells.

6. The method according to claim 5, characterized in that It is expressed by the following formula: （7）； in, To obtain the total number of times of the third SOC data, For the The average SOC of multiple battery cells at a certain moment is expressed by the following formula: （8）； in, For the Moment The SOC of a single battery.

7. The method according to claim 6, characterized in that It is expressed by the following formula: （9）； in, For the The minimum SOC of multiple battery cells at a certain moment is expressed by the following formula: （10）。 8. The method according to claim 7, characterized in that It is expressed by the following formula: （11）； in, For the The maximum SOC of multiple battery cells at a certain moment is expressed by the following formula: （12）。 9. A battery pack SOC estimation device, characterized in that: include: A data acquisition unit, used to acquire the operating parameters of the battery pack at the current moment and the initial parameters at the initial moment; a data processing unit, configured to obtain first SOC data of a plurality of battery cells of a battery pack at a current moment based on the operating parameter, the initial parameter and the ampere-hour integration method, wherein the plurality of first SOC data constitute a first SOC data set; A first data generating unit, configured to obtain a group SOC of the battery pack at a current moment based on the first SOC data set; a condition judgment unit, configured to judge whether each of the first SOC data in the first SOC data set meets a preset condition; a condition response unit, configured to, in response to the first SOC data satisfying a preset condition, record the first SOC data satisfying the preset condition as second SOC data, and all second SOC data constitute a second SOC data set; A second data generating unit, configured to obtain an estimated SOC value of the battery pack at a current moment based on the second SOC data set and the SOC estimation model; A data fusion unit is used to fuse the current SOC estimation value and the battery pack SOC to obtain the final SOC value of the battery pack at the current moment; Among them, the SOC estimation model is expressed by the following formula: （1）； Among them, the final SOC value of the battery pack at the current moment is expressed by the following formula: （2）； in, is the estimated SOC value, is the total number of data in the second SOC data set, The second SOC data set is Second SOC data, For the The weight of the second SOC data, satisfy ; is the final SOC value, For group SOC, is the fusion coefficient, .

10. An electronic device, characterized in that: The electronic device comprises: processor; a memory for storing instructions executable by the processor; The processor is used to read the executable instructions from the memory and execute the executable instructions to implement the method according to any one of claims 1 to 8.

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