Method and device for calculating SOH (state of health) of energy storage system

Abstract

The embodiment of the invention provides a method and device for calculating the SOH of an energy storage system, and the method comprises the steps: calculating the cycle life and the calendar life of a battery in the energy storage system, and obtaining a first SOH value of the battery according to the cycle life and the calendar life; according to the first SOH value of the battery, determining a capacity recession stage of the battery, and based on the capacity recession stage of the battery, determining an SOH calculation mode of the battery; and calculating a real SOH value of the battery according to the SOH calculation mode of the battery.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage BMS, and in particular to a method and device for calculating the state of health (SOH) of an energy storage system. Background Art

[0002] With the development of new energy technologies, secondary batteries represented by lithium batteries have gradually been applied to energy storage systems, electric vehicles, military equipment, aerospace and other fields, bringing great convenience to people's daily production and life. Battery SOH (State of Health) is an important indicator for evaluating battery performance. It is of great significance for understanding the working condition of the battery, predicting battery performance degradation and optimizing battery usage strategies. However, the SOH algorithm is an important component of the battery management system and is an important indicator used to indicate the health of the battery to the user. There are many factors that affect the health of the battery. For example, temperature, number of charge and discharge cycles, usage time, etc. are all important factors that can affect battery degradation. In energy storage application scenarios, the application cost of complex model-based algorithms is relatively high. Therefore, it is very necessary to provide an SOH algorithm that conforms to the battery capacity degradation characteristics. Summary of the Invention

[0003] In view of this, embodiments of the present application provide a method for calculating the state of health (SOH) of an energy storage system. One or more embodiments of the present application also relate to an apparatus for calculating the state of health (SOH) of an energy storage system, a computing device, a computer-readable storage medium, and a computer program to address technical deficiencies in the prior art.

[0004] According to a first aspect of an embodiment of the present application, a method for calculating the state of health (SOH) of an energy storage system is provided, comprising:

[0005] Calculating the cycle life and calendar life of a battery in the energy storage system respectively, and obtaining a first SOH value of the battery according to the cycle life and calendar life;

[0006] determining a capacity decay stage of the battery according to a first SOH value of the battery, and determining a method for calculating the SOH of the battery based on the capacity decay stage of the battery;

[0007] The actual SOH value of the battery is calculated according to the SOH calculation method of the battery.

[0008] Preferably, respectively calculating the cycle life and calendar life of a battery in the energy storage system includes:

[0009] Obtaining the current cumulative discharge capacity, rated capacity, and rated number of charge and discharge cycles of the battery in the energy storage system, and calculating the current cycle life of the battery based on the cumulative discharge capacity, rated capacity, and rated number of charge and discharge cycles;

[0010] Obtain the current system time, factory time, and warranty time of the energy storage system, and calculate the calendar life of the battery based on the current system time, factory time, and warranty time.

[0011] Preferably, obtaining the first SOH value of the battery according to the cycle life and calendar life includes:

[0012] comparing the cycle life to the calendar life;

[0013] If the cycle life is less than the calendar life, taking the cycle life as the first SOH value of the battery;

[0014] If the cycle life is greater than the calendar life, the calendar life is used as the first SOH value of the battery.

[0015] Preferably, determining the capacity decay stage of the battery according to the first SOH value of the battery includes:

[0016] comparing a first SOH value of the battery with a preset battery attenuation value;

[0017] If the first SOH value of the battery is greater than or equal to the battery attenuation value, determining that the capacity decay stage of the battery is a normal stage;

[0018] If the first SOH value of the battery is less than the battery attenuation value, it is determined that the capacity decay stage of the battery is an abnormal stage.

[0019] Preferably, based on the capacity decay stage of the battery, a calculation method for determining the SOH of the battery includes:

[0020] If the capacity decay stage of the battery is a normal stage, determining that the SOH calculation method of the battery is a first SOH calculation method;

[0021] If the capacity decay stage of the battery is an abnormal stage, the SOH calculation method of the battery is determined to be the second SOH calculation method.

[0022] Preferably, according to the SOH calculation method of the battery, calculating the true SOH value of the battery includes:

[0023] Obtain a correspondence table containing different SOH intervals and their corresponding decay factors;

[0024] When it is determined that the SOH calculation method of the battery is the first SOH calculation method, determining a first degradation factor corresponding to the first SOH value of the battery according to the correspondence table;

[0025] The real SOH value of the battery is calculated using the first SOH value of the battery and the first degradation factor.

[0026] Preferably, according to the SOH calculation method of the battery, calculating the true SOH value of the battery includes:

[0027] Obtain a correspondence table containing different SOH intervals and their corresponding decay factors;

[0028] When it is determined that the SOH calculation method of the battery is the second SOH calculation method, determining a second degradation factor corresponding to the first SOH value of the battery according to the correspondence table, and respectively calculating a cycle life degradation rate and a calendar life degradation rate of the battery;

[0029] Calculating the current cycle life of the battery according to the cycle life decay rate of the battery, and calculating the current calendar cycle life of the battery according to the calendar life decay rate of the battery;

[0030] The actual SOH value of the battery is calculated using the current cycle life of the battery, the current calendar cycle life, and the second degradation factor.

[0031] According to a second aspect of an embodiment of the present application, a device for calculating the state of health (SOH) of an energy storage system is provided, comprising:

[0032] a calculation module configured to respectively calculate a cycle life and a calendar life of a battery in the energy storage system, and obtain a first SOH value of the battery according to the cycle life and the calendar life;

[0033] a determination module configured to determine a capacity decay stage of the battery according to a first SOH value of the battery, and determine a method for calculating the SOH of the battery based on the capacity decay stage of the battery;

[0034] The SOH calculation module is configured to calculate the real SOH value of the battery according to the SOH calculation method of the battery.

[0035] According to a third aspect of an embodiment of the present application, a computing device is provided, including:

[0036] memory and processor;

[0037] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement any one of the steps of the method for calculating the state of health (SOH) of an energy storage system.

[0038] According to a fourth aspect of an embodiment of the present application, a computer-readable storage medium is provided, which stores computer-executable instructions. When the instructions are executed by a processor, the steps of any one of the methods for calculating the state of health (SOH) of an energy storage system are implemented.

[0039] According to a fifth aspect of an embodiment of the present application, a computer program is provided, wherein when the computer program is executed in a computer, the computer is caused to execute the steps of the above-mentioned method for calculating the state of health SOH of an energy storage system.

[0040] The solution for calculating the state of health (SOH) of an energy storage system provided in an embodiment of the present application is to respectively calculate the cycle life and calendar life of a battery in the energy storage system, and obtain a first SOH value of the battery based on the cycle life and calendar life; determine the capacity decay stage of the battery based on the first SOH value of the battery, and determine the SOH calculation method of the battery based on the capacity decay stage of the battery; and calculate the true SOH value of the battery based on the SOH calculation method of the battery. The solution for calculating the state of health (SOH) of an energy storage system provided in the embodiment of the present application is specifically designed for industrial and commercial energy storage systems, and aims to take into account cycle life and calendar life, so that the factors affecting battery capacity decay are not limited to the number of charge and discharge cycles. As the usage time increases, it will also have a corresponding impact on the battery life; secondly, different decay factors are added in different SOH intervals, so that the SOH of the battery in different decay stages is closer to the actual battery decay trend and the true value, with relatively higher accuracy; thirdly, after the SOH is less than 70%, the system can still smoothly calculate the battery's SOH and display the battery's decay process; finally, since the actual battery decay rate will become faster and faster after the battery life is less than 70%, the maximum decay rate of the cycle life and calendar life is taken to calculate the SOH after the SOH is less than 70%, which is more in line with the characteristics of battery decay. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a flow chart of a method for calculating the state of health (SOH) of an energy storage system provided by one embodiment of the present application;

[0042] Figure 2 1 is a schematic diagram of a device for calculating the state of health (SOH) of an energy storage system provided by one embodiment of the present application;

[0043] Figure 3This is an overall flow chart of an algorithm method for providing an SOH greater than or equal to 70% according to an embodiment of the present application;

[0044] Figure 4 This is an overall flow chart of an algorithm method for achieving an SOH of less than 70% provided by one embodiment of the present application;

[0045] Figure 5 This is a structural block diagram of a computing device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0046] The following description sets forth many specific details to facilitate a thorough understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar generalizations without violating the scope of the present application. Therefore, the present application is not limited to the specific implementations disclosed below.

[0047] The terms used in one or more embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of the present application. The singular forms "a", "the" and "the" used in one or more embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in one or more embodiments of the present application refers to and includes any or all possible combinations of one or more associated listed items.

[0048] It should be understood that although the terms first, second, etc. may be used to describe various information in one or more embodiments of the present application, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of one or more embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0049] In energy storage applications, the SOH of an energy storage system should reflect the number of charge and discharge cycles and operating hours of the system's batteries—that is, the battery's cycle life and calendar life. This should smoothly reflect the battery's health throughout its entire lifecycle and conform to normal battery degradation characteristics. Furthermore, compared to SOH algorithms that calculate cycle life and calendar life, model-based algorithms offer less accuracy improvement. Therefore, an SOH algorithm that conforms to battery capacity degradation characteristics is effective.

[0050] In this application, a method for calculating the state of health (SOH) of an energy storage system is provided. This application also relates to an apparatus for calculating the state of health (SOH) of an energy storage system, a computing device, a computer-readable storage medium, and a computer program, which are described in detail one by one in the following embodiments.

[0051] Figure 1 A flow chart of a method for calculating the state of health (SOH) of an energy storage system according to an embodiment of the present application is shown, which specifically includes the following steps.

[0052] Step S101: Calculating the cycle life and calendar life of a battery in an energy storage system respectively, and obtaining a first SOH value of the battery according to the cycle life and calendar life;

[0053] In an optional embodiment, respectively calculating the cycle life and calendar life of a battery in the energy storage system includes:

[0054] Obtaining the current cumulative discharge capacity, rated capacity, and rated number of charge and discharge cycles of the battery in the energy storage system, and calculating the current cycle life of the battery based on the cumulative discharge capacity, rated capacity, and rated number of charge and discharge cycles;

[0055] Obtain the current system time, factory time, and warranty time of the energy storage system, and calculate the calendar life of the battery based on the current system time, factory time, and warranty time.

[0056] In an optional embodiment, obtaining a first SOH value of the battery according to the cycle life and calendar life includes:

[0057] comparing the cycle life to the calendar life;

[0058] If the cycle life is less than the calendar life, taking the cycle life as the first SOH value of the battery;

[0059] If the cycle life is greater than the calendar life, the calendar life is used as the first SOH value of the battery.

[0060] Step S102: determining a capacity decay stage of the battery according to a first SOH value of the battery, and determining a method for calculating the SOH of the battery based on the capacity decay stage of the battery;

[0061] In an optional implementation, determining the capacity decay stage of the battery according to the first SOH value of the battery includes:

[0062] comparing a first SOH value of the battery with a preset battery attenuation value;

[0063] If the first SOH value of the battery is greater than or equal to the battery attenuation value, determining that the capacity decay stage of the battery is a normal stage;

[0064] If the first SOH value of the battery is less than the battery attenuation value, it is determined that the capacity decay stage of the battery is an abnormal stage. Wherein, the battery attenuation value is preferably 70%, and may also be other values.

[0065] In an optional embodiment, based on the capacity decay stage of the battery, determining the calculation method of the SOH of the battery includes:

[0066] If the capacity decay stage of the battery is a normal stage, determining that the SOH calculation method of the battery is a first SOH calculation method;

[0067] If the capacity decay stage of the battery is an abnormal stage, the SOH calculation method of the battery is determined to be the second SOH calculation method.

[0068] Step S103: Calculate the actual SOH value of the battery according to the SOH calculation method of the battery.

[0069] In an optional embodiment, according to the SOH calculation method of the battery, calculating the true SOH value of the battery includes:

[0070] Obtain a correspondence table containing different SOH intervals and their corresponding decay factors;

[0071] When it is determined that the SOH calculation method of the battery is the first SOH calculation method, determining a first degradation factor corresponding to the first SOH value of the battery according to the correspondence table;

[0072] The real SOH value of the battery is calculated using the first SOH value of the battery and the first degradation factor.

[0073] In an optional embodiment, according to the SOH calculation method of the battery, calculating the true SOH value of the battery includes:

[0074] Obtain a correspondence table containing different SOH intervals and their corresponding decay factors;

[0075] When it is determined that the SOH calculation method of the battery is the second SOH calculation method, determining a second degradation factor corresponding to the first SOH value of the battery according to the correspondence table, and respectively calculating a cycle life degradation rate and a calendar life degradation rate of the battery;

[0076] Calculating the current cycle life of the battery according to the cycle life decay rate of the battery, and calculating the current calendar cycle life of the battery according to the calendar life decay rate of the battery;

[0077] The actual SOH value of the battery is calculated using the current cycle life of the battery, the current calendar cycle life, and the second degradation factor.

[0078] The solution for calculating the state of health (SOH) of an energy storage system provided in the embodiment of the present application is specifically designed for industrial and commercial energy storage systems, and aims to take into account cycle life and calendar life, so that the factors affecting battery capacity decay are not limited to the number of charge and discharge cycles. As the usage time increases, it will also have a corresponding impact on the battery life; secondly, different decay factors are added in different SOH intervals, so that the SOH of the battery in different decay stages is closer to the actual battery decay trend and the true value, with relatively higher accuracy; thirdly, after the SOH is less than 70%, the system can still smoothly calculate the battery's SOH and display the battery's decay process; finally, since the actual battery decay rate will become faster and faster after the battery life is less than 70%, the maximum decay rate of the cycle life and calendar life is taken to calculate the SOH after the SOH is less than 70%, which is more in line with the characteristics of battery decay.

[0079] In calculating the SOH of the energy storage system, the present application firstly considers not only the attenuation of the battery's cycle life caused by the number of charge and discharge cycles of the battery, but also the attenuation of the calendar life caused by the working hours; secondly, in calculating the SOH of the energy storage system, the attenuation of the SOH is made to conform to the overall trend of battery capacity attenuation; finally, in calculating the SOH of the energy storage system, after the SOH decays to 70%, it is considered that the battery life has ended, and a message to replace the battery is prompted. At this point, even if the user continues to use it, the system SOH is always fixed at 70%. In theory, after the battery decays to 70%, the battery decay rate will become faster and faster. Therefore, after the battery decays to 70%, the system can still smoothly display the battery's health status in a manner that conforms to the battery degradation characteristics.

[0080] During the charge and discharge process, the cumulative discharge capacity of the battery is calculated at all times, and the battery cycle life is calculated by adding the cumulative discharge capacity to the current rated capacity of the battery. Similarly, the calendar life of the battery is obtained by adding the current system time and the factory time. Finally, the minimum value of the two is taken and converted to obtain the current SOH of the battery.

[0081] During the battery capacity decay process, the decay factor τ is added to make the SOH decay conform to the overall characteristics of battery capacity decay:

[0082]

[0083] During the gradual decay of the battery's state of health, generally when the battery's state of health decays to 70%, it is considered that the battery life has ended and the conditions for battery replacement have been met. However, due to factors such as the temporary non-satisfaction of the replacement conditions, the battery's state of health continues to decay. It is necessary to calculate the battery SOH based on the decay rate of the cycle life and calendar life in the process of SOH from the current moment to 75%.

[0084] The following combined Figure 3 Taking the application of the method for calculating the health status SOH of the energy storage system provided by this application in the field of power system management as an example, the method for calculating the health status SOH of the energy storage system is further explained. Figure 3 The flowchart of the algorithm for determining if the SOH is greater than or equal to 70% according to one embodiment of the present application is shown. Specifically, the algorithm includes: calculating the number of charge and discharge cycles by accumulating discharge capacity, and comparing this with the rated number of charge and discharge cycles to calculate the cycle life; similarly, calculating the calendar life of the system by comparing the operating time and the warranty period, taking the minimum value, and finally converting the SOH to the range of [70%, 100%]. In addition, different decay factors are used depending on the range of the SOH:

[0085]

[0086] Note: The decay factor can be set to different values depending on the project. A decay factor greater than 1 indicates accelerated battery aging, while a decay factor less than 1 indicates slower battery aging. Setting the decay factor allows you to better reflect the actual battery degradation trend during operation.

[0087] During the operation of the energy storage BMS system, when the SOH is greater than or equal to 70%, the SOH is calculated as follows: Figure 3 As shown, the specific steps include:

[0088] First, obtain the cumulative discharge capacity, rated capacity, and rated charge and discharge cycle number, and calculate the percentage of cycle number to capacity attenuation number:

[0089] soh_cycle = cumulative discharge capacity / (rated capacity * rated charge and discharge cycle number) * 100%;

[0090] Then, obtain the system time, factory time, and warranty time, and calculate the percentage of running time to warranty time:

[0091] soh_calendar = (system time - factory time) / warranty time * 100%;

[0092] Secondly, determine the relationship between cycle life and calendar life:

[0093] soh_temp=min(soh_cycle,soh_calendar);

[0094] Finally, different decay factors are obtained according to the SOH range, and soh_temp is converted to the range of 70% to 100% to calculate the actual SOH:

[0095] soh=τ*(100-0.3*(100-soh_temp)).

[0096] soh is the actual SOH; τ is the decay factor corresponding to the SOH interval.

[0097] The following combined Figure 4 Taking the application of the method for calculating the health status SOH of the energy storage system provided by this application in the field of power system management as an example, the method for calculating the health status SOH of the energy storage system is further explained. Figure 4 A flowchart of the processing process of an algorithm for SOH less than 70% provided by one embodiment of the present application is shown. Specifically, the flowchart includes: when the SOH is less than 70%, first obtaining the cycle number cycle_75% when the cycle life is 75% and the cycle number cycle_now at the current moment; simultaneously obtaining the operating time operating_75% when the calendar life = 75% and the operating time operating_now at the current moment, and calculating the cycle life decay rate and the calendar life decay rate:

[0098]

[0099] Among them, K cycle is the cycle life attenuation rate; K calendar is the calendar life decay rate; cycle_now is the number of cycles at the current moment; operating_now is the operating time at the current moment; cycle_75% is the number of cycles when the cycle life is 75%; operating_75% is the operating time when the calendar life = 75%.

[0100] And the cycle life decay rate and calendar life decay rate are compared with the decay rate at the previous moment, and the maximum absolute value K_cycle_max and K_calendar_max are taken. The cycle life and calendar life are calculated respectively, and the minimum value is taken.

[0101] During the operation of the energy storage BMS system, when SOH is less than 70%, the calculation of SOH is as follows: Figure 4 As shown, the specific steps include:

[0102] First, obtain the number of cycles when the cycle life is 75% cycle_75% and the number of cycles at the current moment cycle_now, and calculate the decay rate of the cycle life K_cycle(t):

[0103] K_cycle(t)=(soh-75%) / (cycle_now-cycle_75%)

[0104] K_cycle_max(t)=max(|K_cycle(t)|,|K_cycle(t-1)|);

[0105] K_cycle(t) is the decay rate of the cycle life at the current moment; K_cycle(t-1) is the decay rate of the cycle life at the previous moment.

[0106] Then, obtain the operating time operating_75% when the calendar life is 75% and the operating time operating_now at the current moment, and calculate the decay rate of the calendar life K_calendar(t):

[0107] K_calendar(t)=(soh-75%) / (operating_now-operating_75%)

[0108] K_calendar_max(t)=max(|K_calendar(t)|,|K_calendar(t-1)|);

[0109] Next, calculate the cycle life and calendar life at this point:

[0110] soh_cycle=soh_cycle+K_cycle_max*cycle

[0111] soh_calendar=soh_calendar+K_calendar_max*operating_time

[0112] Where cycle is the number of charge and discharge cycles experienced after the SOH is less than 70%, and operating_time is the operating time experienced after the SOH is less than 70%.

[0113] Finally, determine the size of soh_cycle and soh_calendar, take the minimum value, and obtain the corresponding decay factor based on the SOH interval:

[0114] soh=τ*min(soh_cycle, soh_calendar)

[0115] This application takes into account the cycle life and calendar life, so that the factors affecting the battery capacity decay are not limited to the number of charge and discharge cycles. As the usage time increases, it will also have a corresponding impact on the battery life; different decay factors are added in different SOH intervals, so that the battery's SOH is closer to the actual battery decay trend in different decay stages, closer to the true value, and relatively higher in accuracy; after the SOH is less than 70%, the system can still smoothly calculate the battery's SOH and display the battery's decay process; according to the actual battery life is less than 70%, the battery's decay rate will become faster and faster, so after the SOH is less than 70%, the maximum decay rate of the cycle life and calendar life is taken to calculate the SOH, which is more in line with the characteristics of battery decay.

[0116] This application also provides an embodiment of a device for calculating the state of health (SOH) of an energy storage system. Figure 2 FIG1 shows a schematic diagram of a device for calculating the state of health (SOH) of an energy storage system provided by an embodiment of the present application. Figure 2 As shown, the device includes:

[0117] The calculation module 201 is configured to respectively calculate the cycle life and calendar life of a battery in the energy storage system, and obtain a first SOH value of the battery according to the cycle life and calendar life;

[0118] a determination module 202 configured to determine a capacity decay stage of the battery according to a first SOH value of the battery, and determine a method for calculating the SOH of the battery based on the capacity decay stage of the battery;

[0119] The SOH calculation module 203 is configured to calculate the real SOH value of the battery according to the SOH calculation method of the battery.

[0120] The above is a schematic scheme of an apparatus for calculating the state of health (SOH) of an energy storage system according to this embodiment. It should be noted that the technical scheme of the apparatus for calculating the state of health (SOH) of an energy storage system and the technical scheme of the method for calculating the state of health (SOH) of an energy storage system described above are based on the same concept. For details not described in detail in the technical scheme of the apparatus for calculating the state of health (SOH) of an energy storage system, please refer to the description of the technical scheme of the method for calculating the state of health (SOH) of an energy storage system described above.

[0121] Figure 5 The block diagram shows a structure of a computing device 500 according to one embodiment of the present application. The components of the computing device 500 include, but are not limited to, a memory 510 and a processor 520. The processor 520 is connected to the memory 510 via a bus 530, and a database 550 is used to store data.

[0122] The computing device 500 also includes an access device 540 that enables the computing device 500 to communicate via one or more networks 560. Examples of such networks include a public switched telephone network (PSTN), a local area network (LAN), a wide area network (WAN), a personal area network (PAN), or a combination of communication networks such as the Internet. The access device 540 may include one or more of any type of network interface (e.g., a network interface card (NIC)), whether wired or wireless, such as an IEEE 802.11 wireless local area network (WLAN) wireless interface, a Worldwide Interoperability for Microwave Access (Wi-MAX) interface, an Ethernet interface, a universal serial bus (USB) interface, a cellular network interface, a Bluetooth interface, a near field communication (NFC) interface, and the like.

[0123] In one embodiment of the present application, the above components of the computing device 500 and Figure 5 Other components not shown in the figure may also be connected to each other, for example, via a bus. Figure 5 The computing device structure block diagram shown is for illustrative purposes only and is not intended to limit the scope of the present application. Those skilled in the art may add or replace other components as needed.

[0124] Computing device 500 can be any type of stationary or mobile computing device, including a mobile computer or mobile computing device (e.g., a tablet computer, a personal digital assistant, a laptop computer, a notebook computer, a netbook computer, etc.), a mobile phone (e.g., a smartphone), a wearable computing device (e.g., a smartwatch, smart glasses, etc.), or other types of mobile devices, or a stationary computing device such as a desktop computer or PC. Computing device 500 can also be a mobile or stationary server.

[0125] The processor 520 is configured to execute the following computer-executable instructions, which, when executed by the processor, implement the steps of the method for calculating the state of health (SOH) of the energy storage system.

[0126] The above is a schematic diagram of a computing device according to this embodiment. It should be noted that the technical solution of this computing device and the technical solution of the method for calculating the state of health (SOH) of an energy storage system described above are based on the same concept. For details not described in detail in the technical solution of the computing device, please refer to the description of the technical solution of the method for calculating the state of health (SOH) of an energy storage system described above.

[0127] An embodiment of the present application further provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the method for calculating the state of health (SOH) of an energy storage system.

[0128] The above is a schematic diagram of a computer-readable storage medium according to this embodiment. It should be noted that the technical solution of this storage medium and the technical solution of the method for calculating the state of health (SOH) of an energy storage system described above are based on the same concept. For details not described in detail in the technical solution of the storage medium, please refer to the description of the technical solution of the method for calculating the state of health (SOH) of an energy storage system described above.

[0129] An embodiment of the present application further provides a computer program, wherein when the computer program is executed in a computer, the computer is caused to execute the steps of the above-mentioned method for calculating the state of health (SOH) of an energy storage system.

[0130] The above is a schematic scheme of a computer program of this embodiment. It should be noted that the technical scheme of this computer program and the technical scheme of the method for calculating the state of health (SOH) of an energy storage system described above are based on the same concept. For details not described in detail in the technical scheme of the computer program, please refer to the description of the technical scheme of the method for calculating the state of health (SOH) of an energy storage system described above.

[0131] The foregoing description describes specific embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in an order different from that described in the embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order shown or the sequential order to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0132] The computer instructions include computer program code, which may be in source code form, object code form, executable file, or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content contained in the computer-readable medium may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0133] It should be noted that for the aforementioned method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the embodiments of the present application are not limited by the order of the actions described, because according to the embodiments of the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the embodiments of the present application.

[0134] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0135] The preferred embodiments of the present application disclosed above are intended only to help illustrate the present application. The optional embodiments do not describe all details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made based on the content of the embodiments of the present application. This application selects and specifically describes these embodiments in order to better explain the principles and practical applications of the embodiments of the present application, so that those skilled in the art can better understand and utilize the present application. This application is limited only by the claims and their full scope and equivalents.

Claims

1. A method for calculating the state of health (SOH) of an energy storage system, characterized in that: include: Calculating the cycle life and calendar life of a battery in the energy storage system respectively, and obtaining a first SOH value of the battery according to the cycle life and calendar life; determining a capacity decay stage of the battery according to a first SOH value of the battery, and determining a method for calculating the SOH of the battery based on the capacity decay stage of the battery; The actual SOH value of the battery is calculated according to the SOH calculation method of the battery.

2. The method according to claim 1, characterized in that Calculating the cycle life and calendar life of batteries in energy storage systems separately includes: Obtaining the current cumulative discharge capacity, rated capacity, and rated number of charge and discharge cycles of the battery in the energy storage system, and calculating the current cycle life of the battery based on the cumulative discharge capacity, rated capacity, and rated number of charge and discharge cycles; Obtain the current system time, factory time, and warranty time of the energy storage system, and calculate the calendar life of the battery based on the current system time, factory time, and warranty time.

3. The method according to claim 2, characterized in that Obtaining a first SOH value of the battery according to the cycle life and calendar life includes: comparing the cycle life to the calendar life; If the cycle life is less than the calendar life, taking the cycle life as the first SOH value of the battery; If the cycle life is greater than the calendar life, the calendar life is used as the first SOH value of the battery.

4. The method according to claim 3, characterized in that Determining the capacity decay stage of the battery according to the first SOH value of the battery includes: comparing a first SOH value of the battery with a preset battery attenuation value; If the first SOH value of the battery is greater than or equal to the battery attenuation value, determining that the capacity decay stage of the battery is a normal stage; If the first SOH value of the battery is less than the battery attenuation value, it is determined that the capacity decay stage of the battery is an abnormal stage.

5. The method according to claim 4, characterized in that Based on the capacity decay stage of the battery, a calculation method for determining the SOH of the battery includes: If the capacity decay stage of the battery is a normal stage, determining that the SOH calculation method of the battery is a first SOH calculation method; If the capacity decay stage of the battery is an abnormal stage, the SOH calculation method of the battery is determined to be the second SOH calculation method.

6. The method according to claim 5, characterized in that According to the battery SOH calculation method, calculating the actual SOH value of the battery includes: Obtain a correspondence table containing different SOH intervals and their corresponding decay factors; When it is determined that the SOH calculation method of the battery is the first SOH calculation method, determining a first degradation factor corresponding to the first SOH value of the battery according to the correspondence table; The real SOH value of the battery is calculated using the first SOH value of the battery and the first degradation factor.

7. The method according to claim 5, characterized in that According to the battery SOH calculation method, calculating the actual SOH value of the battery includes: Obtain a correspondence table containing different SOH intervals and their corresponding decay factors; When it is determined that the SOH calculation method of the battery is the second SOH calculation method, determining a second degradation factor corresponding to the first SOH value of the battery according to the correspondence table, and respectively calculating a cycle life degradation rate and a calendar life degradation rate of the battery; Calculating the current cycle life of the battery according to the cycle life decay rate of the battery, and calculating the current calendar cycle life of the battery according to the calendar life decay rate of the battery; The actual SOH value of the battery is calculated using the current cycle life of the battery, the current calendar cycle life, and the second degradation factor.

8. A device for calculating the state of health (SOH) of an energy storage system, characterized in that: include: a calculation module configured to respectively calculate a cycle life and a calendar life of a battery in the energy storage system, and obtain a first SOH value of the battery according to the cycle life and the calendar life; a determination module configured to determine a capacity decay stage of the battery according to a first SOH value of the battery, and determine a method for calculating the SOH of the battery based on the capacity decay stage of the battery; The SOH calculation module is configured to calculate the real SOH value of the battery according to the SOH calculation method of the battery.

9. A computing device comprising: memory and processor; The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the method for calculating the health state SOH of the energy storage system as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions, when executed by a processor, implement the steps of the method for calculating the state of health (SOH) of an energy storage system according to any one of claims 1 to 7.

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