Power battery SOH (state of health) estimation method and device

Abstract

The invention discloses a power battery SOH estimation method and device. The method comprises the following steps: acquiring current-moment voltage, current and current-moment temperature of a power battery, and recording first accumulated working time when the current-moment temperature is greater than or equal to a preset temperature; according to the current-moment voltage, the current-moment current and the current-moment temperature, calculating an accumulated discharge capacity throughput SOH, a first attenuation SOH, a second attenuation SOH and a third attenuation SOH of the power battery at the current moment; and according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH and the third attenuation SOH, estimating the current SOH of the power battery. According to the method, the discharge capacity throughput, the calendar life, the high temperature and the high SOC working time of the battery serve as SOH decisive parameters, the influence factors of the SOH of the battery are considered in a multi-dimensional mode, parameter singleness is avoided, and due to the fact that the influence factors of the SOH of the battery are considered in a multi-dimensional mode, the estimation precision of the SOH of the battery is effectively improved, and estimation errors are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and in particular to a method and device for estimating the state of health (SOH) of a power battery. Background Art

[0002] Lithium battery state of health (SOH) estimation is one of the core functions of battery management systems. The main methods can be divided into the following categories: methods based on capacity and internal resistance experimental analysis, model-based methods, and data-driven methods. Among them, the commonly used methods in the automotive field are:

[0003] (1) Cumulative capacity throughput method: This method calculates SOH by counting the total charge and discharge capacity of the battery from the initial state (BOL, Beginning of Life) to the current moment and comparing it with the total capacity throughput at the end of the battery life (EOL, End of Life). (2) Dynamic capacity throughput combined with internal resistance method: SOH is estimated by combining capacity throughput and internal resistance changes. (3) Capacity attenuation model based on cycle number: SOH is estimated by accumulating the number of charge and discharge cycles; (4) Data-driven capacity throughput model: Combined with machine learning methods such as LSTM and XGBoost, SOH degradation rules are learned from capacity throughput data, and charge / discharge capacity and voltage curve features such as constant current charging time and IC curve peak are extracted as input to train regression models such as CNN-Transformer and LSTM-XGBoost to predict SOH.

[0004] The above method has the problems of single parameters, low estimation accuracy and large errors. Summary of the Invention

[0005] The present invention provides a method and device for estimating the state of health (SOH) of a power battery, in order to solve the problems of the prior art of single parameters, low estimation accuracy and large errors.

[0006] According to one aspect of the present invention, a method for estimating the state of health (SOH) of a power battery is provided, comprising:

[0007] Obtaining the current voltage, current, and temperature of the power battery, and recording the first accumulated operating time during which the current temperature is greater than or equal to a preset temperature;

[0008] Calculating the cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH of the power battery at the current moment according to the current voltage, the current, and the current temperature;

[0009] The current SOH of the power battery is estimated according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH.

[0010] Optionally, before obtaining the current voltage, current, and temperature of the power battery, the method further includes:

[0011] Retrieve the last power-off time and record the current power-on time.

[0012] Optionally, calculating the cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH of the power battery at the current moment according to the current voltage, the current, and the current temperature includes:

[0013] Calculating the current state of charge (SOC) and the cumulative discharge capacity throughput of the power battery according to the current voltage and the current current, and recording a second cumulative operating time during which the current SOC is greater than or equal to a preset SOC;

[0014] Calculating the cumulative discharge capacity throughput SOH of the power battery at the current moment according to the cumulative discharge capacity throughput at the current moment and the preset total capacity throughput;

[0015] Calculating a first attenuation SOH according to the power-off hold time obtained from the last power-off time and the current power-on time, and a first preset attenuation coefficient;

[0016] Calculating a second attenuation SOH according to the second accumulated working time and a second preset attenuation coefficient;

[0017] A third attenuation SOH is calculated according to the first accumulated operating time and a third preset attenuation coefficient.

[0018] Optionally, estimating the current SOH of the power battery according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH includes:

[0019] Use the following formula to estimate the current SOH of the power battery;

[0020] SOH=100%-SOH cap -SOH calendar -SOH HighSOC -SOH HighT Where SOH cap is the cumulative capacity throughput SOH, SOH calendar is the first attenuation SOH, SOH HighSOC is the second attenuation SOH, SOH HighT It is the third attenuation SOH.

[0021] Optionally, before obtaining the current voltage, current, and temperature of the power battery, the method further includes:

[0022] Determine whether a power-off signal is detected;

[0023] If yes, the power-off time is recorded; if no, the step of determining whether a power-off signal is detected is continued.

[0024] Optionally, the calculating the cumulative discharge capacity throughput SOH of the power battery at the current moment according to the cumulative discharge capacity throughput at the current moment and the preset total capacity throughput includes:

[0025] The following formula is used to calculate the cumulative discharge capacity throughput SOH of the power battery at the current moment;

[0026] Where SOH cap is the cumulative discharge capacity throughput SOH of the power battery at the current moment, Cap(k) is the cumulative discharge capacity throughput from the first power-on to the current moment, and Cap(Total) is the preset total capacity throughput.

[0027] Optionally, calculating the first attenuation SOH according to the power-off hold time obtained from the last power-off time and the current power-on time, and a first preset attenuation coefficient includes:

[0028] The first attenuation SOH is calculated using the following formula:

[0029] SOH calendar =a*T1Sk1; where SOH calendar is the first attenuation SOH, a is a first preset attenuation coefficient, and T1Sk1 is the power-off hold time obtained according to the last power-off time and the current power-on time.

[0030] Optionally, calculating the second attenuation SOH according to the second accumulated operating time and the second preset attenuation coefficient includes:

[0031] The second attenuation SOH is calculated using the following formula:

[0032] SOH HighSOC =b*T2Sk2; where SOH HighSOC is the second attenuation SOH, b is the second preset attenuation coefficient, and T2Sk2 is the second accumulated working time.

[0033] Optionally, calculating the third attenuation SOH according to the first accumulated operating time and a third preset attenuation coefficient includes:

[0034] The third attenuation SOH is calculated using the following formula:

[0035] SOH HighT =c*T3Sk3; where SOH HighT is the third attenuation SOH, c is the third preset attenuation coefficient, and T3Sk3 is the first accumulated working time.

[0036] According to another aspect of the present invention, a power battery SOH estimation device is provided, comprising:

[0037] an acquisition module, the acquisition module being configured to acquire a current voltage, a current current, and a current temperature of the power battery, and record a first accumulated operating time during which the current temperature is greater than or equal to a preset temperature;

[0038] a calculation module, configured to calculate the cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH of the power battery at the current moment according to the current voltage, the current, and the current temperature;

[0039] An estimation module is configured to estimate the current SOH of the power battery according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH.

[0040] The embodiment of the present invention provides a method and device for estimating the SOH of a power battery. The method includes: obtaining the current voltage, current current and temperature of the power battery, and recording the first cumulative working time when the current temperature is greater than or equal to the preset temperature; calculating the cumulative discharge capacity throughput SOH, first attenuation SOH, second attenuation SOH and third attenuation SOH of the power battery at the current moment according to the current voltage, current current and temperature; estimating the current SOH of the power battery according to the cumulative capacity throughput SOH, first attenuation SOH, second attenuation SOH and third attenuation SOH. The technical solution provided by the embodiment of the present invention takes the battery discharge capacity throughput, calendar life, high temperature and high SOC working time as the SOH determining parameters, considers the influencing factors of the battery SOH in multiple dimensions, avoids the single parameter, and effectively improves the estimation accuracy of the battery SOH and reduces the estimation error due to the multi-dimensional consideration of the influencing factors of the battery SOH.

[0041] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 A flow chart of a power battery SOH estimation method provided by an embodiment of the present invention;

[0044] Figure 2 A flowchart of another power battery SOH estimation method provided by an embodiment of the present invention;

[0045] Figure 3 A flow chart of another method for estimating SOH of a power battery provided by an embodiment of the present invention;

[0046] Figure 4 A schematic structural diagram of a power battery SOH estimation device provided by an embodiment of the present invention;

[0047] Figure 5 A schematic diagram of the structure of an electronic device for a power battery SOH estimation method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0049] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0050] Figure 1This is a flow chart of a power battery SOH estimation method provided by an embodiment of the present invention. This embodiment is applicable to the estimation of the SOH of automotive lithium-ion power batteries. The method can be executed by a power battery SOH estimation device, which can be implemented in the form of hardware and / or software and can be configured in any electronic device with communication function. Figure 1 , the method comprising:

[0051] S110: Obtain the current voltage, current, and temperature of the power battery, and record the first accumulated working time during which the current temperature is greater than or equal to a preset temperature.

[0052] The preset temperature can be set based on battery safety specifications or performance requirements. Exceeding this temperature will affect battery life and, in severe cases, pose a safety risk. The preset temperature is typically set at 45°C. The first accumulated operating time is the cumulative continuous operating time of the battery system at a current temperature greater than or equal to the preset temperature. This refers to the cumulative continuous operating time of the battery system at temperatures ≥45°C.

[0053] Specifically, the battery management system obtains the current voltage, current and temperature of the power battery at the current moment; by collecting these three parameters in real time, the working status of the power battery, such as charging and discharging power, energy loss, temperature change, etc., is monitored to provide data support for the status assessment and safety protection of the Battery Management System (BMS).

[0054] S120 , calculating the current cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH of the power battery according to the current voltage, the current, and the current temperature.

[0055] Among them, the first attenuation SOH is the calendar life attenuation SOH; the second attenuation SOH is the attenuation SOH of the battery system working at a high SOC, where high SOC means SOC greater than or equal to 90%; the third attenuation SOH is the attenuation SOH of the battery system working at ≥45°C.

[0056] Specifically, according to the current voltage, the state of charge (SOC) of the power battery at the current moment can be determined, and according to the current SOC, the cumulative working time when the SOC is greater than or equal to 90% can be recorded; according to the current current and time, the discharge capacity throughput of the power battery can be determined; according to the current temperature, the cumulative working time when the current temperature is greater than or equal to the preset temperature can be recorded; before obtaining the current voltage, current and temperature of the power battery, it is necessary to retrieve the last power-off time and record the current power-on time. The power-off shelving time of the battery system can be obtained through the last power-off time and the current power-on time; according to the cumulative discharge capacity throughput, the power-off shelving time of the battery system, the cumulative working time when the current temperature is greater than or equal to the preset temperature, the cumulative working time when the SOC is greater than or equal to 90% and the preset parameters, the cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH and the third attenuation SOH of the power battery at the current moment can be calculated respectively.

[0057] S130 : Estimate the current SOH of the power battery according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH.

[0058] Specifically, the current SOH of the power battery is estimated based on the cumulative capacity throughput SOH, the first decay SOH, the second decay SOH, and the third decay SOH, using a preset SOH prediction model. The preset SOH prediction model includes the relationship between the total SOH (i.e., 100% SOH) and the cumulative capacity throughput SOH, the first decay SOH, the second decay SOH, and the third decay SOH. For example, the difference between the cumulative capacity throughput SOH, the first decay SOH, the second decay SOH, and the third decay SOH is sequentially subtracted from 100% SOH to obtain the current SOH of the power battery.

[0059] The embodiment of the present invention provides a method and device for estimating the SOH of a power battery. The method includes: obtaining the current voltage, current current and temperature of the power battery, and recording the first cumulative working time when the current temperature is greater than or equal to the preset temperature; calculating the cumulative discharge capacity throughput SOH, first attenuation SOH, second attenuation SOH and third attenuation SOH of the power battery at the current moment according to the current voltage, current current and temperature; estimating the current SOH of the power battery according to the cumulative capacity throughput SOH, first attenuation SOH, second attenuation SOH and third attenuation SOH. The technical solution provided by the embodiment of the present invention takes the battery discharge capacity throughput, calendar life, high temperature and high SOC working time as the SOH determining parameters, considers the influencing factors of the battery SOH in multiple dimensions, avoids the single parameter, and effectively improves the estimation accuracy of the battery SOH and reduces the estimation error due to the multi-dimensional consideration of the influencing factors of the battery SOH.

[0060] Figure 2 This is a flow chart of another power battery SOH estimation method provided by an embodiment of the present invention. The embodiment of the present invention further refines the above embodiment on the basis of the above embodiment. Figure 2 ,

[0061] Optionally, before step S110, the method further includes:

[0062] S210: Retrieve the last power-off time and record the current power-on time.

[0063] Specifically, the battery management system retrieves the last power-off time and records the current power-on time.

[0064] S220 , determining whether a power-off signal is detected; if so, executing S230 ; if not, continuing to execute S220 .

[0065] S230: Record the power-off time.

[0066] In some other embodiments, optionally, step S120 specifically includes:

[0067] The current state of charge (SOC) and the accumulated discharge capacity throughput of the power battery are calculated according to the current voltage and the current current, and the second accumulated working time during which the current SOC is greater than or equal to the preset SOC is recorded.

[0068] The cumulative discharge capacity throughput SOH of the power battery at the current moment is calculated based on the cumulative discharge capacity throughput at the current moment and the preset total capacity throughput.

[0069] Specifically, the following formula is used to calculate the cumulative discharge capacity throughput SOH of the power battery at the current moment;

[0070] Where SOH cap is the cumulative discharge capacity throughput SOH of the power battery at the current moment, Cap(k) is the cumulative discharge capacity throughput from the first power-on to the current moment, and Cap(Total) is the preset total capacity throughput.

[0071] A first attenuation SOH is calculated according to the power-off hold time obtained from the last power-off time and the current power-on time, and a first preset attenuation coefficient.

[0072] Among them, the first preset attenuation coefficient is the power battery calendar life attenuation coefficient, which can be pre-set after being obtained through a large number of laboratory tests.

[0073] Specifically, the first attenuation SOH is calculated using the following formula:

[0074] SOH calendar =a*T1Sk1; where SOH calendar is the first attenuation SOH, a is a first preset attenuation coefficient, and T1Sk1 is the power-off hold time obtained according to the last power-off time and the current power-on time.

[0075] A second decay SOH is calculated according to the second accumulated operating time and the second preset decay coefficient.

[0076] The second attenuation coefficient is a attenuation coefficient when the battery has a high SOC, that is, the battery has a current SOC of ≥90%, which can be obtained through a large number of laboratory tests and then pre-set.

[0077] Specifically, the second attenuation SOH is calculated using the following formula:

[0078] SOH HighSOC =b*T2Sk2; where SOH HighSOC is the second attenuation SOH, b is the second preset attenuation coefficient, and T2Sk2 is the second accumulated working time.

[0079] A third attenuation SOH is calculated according to the first accumulated operating time and a third preset attenuation coefficient.

[0080] The third preset attenuation coefficient is the attenuation coefficient for a high battery temperature, that is, a current battery temperature ≥ 45° C., which can be determined through a large number of laboratory tests and then pre-set.

[0081] Specifically, the third attenuation SOH is calculated using the following formula:

[0082] SOH HighT =c*T3Sk3; where SOH HighTis the third attenuation SOH, c is the third preset attenuation coefficient, and T3Sk3 is the first accumulated working time.

[0083] In some special embodiments, optionally, S130 specifically includes:

[0084] Use the following formula to estimate the current SOH of the power battery;

[0085] SOH=100%-SOH cap -SOH calendar -SOH HighSOC -SOH HighT Where SOH cap is the cumulative capacity throughput SOH, SOH calendar is the first attenuation SOH, SOH HighSOC is the second attenuation SOH, SOH HighT It is the third attenuation SOH.

[0086] The following is a detailed explanation of the power battery SOH estimation method provided by the present invention with reference to specific embodiments. Figure 3 A flowchart of another method for estimating SOH of a power battery provided by an embodiment of the present invention is provided. Figure 3 , the method comprising:

[0087] S310: Obtain the current voltage, current, and temperature of the power battery.

[0088] S320: Record the first accumulated working time during which the current temperature is greater than or equal to the preset temperature.

[0089] S330 : Calculate the current SOC and the accumulated discharge capacity throughput of the power battery according to the current voltage and the current.

[0090] S340: Record the second accumulated working time during which the current SOC is greater than or equal to the preset SOC.

[0091] S350: Calculate the cumulative discharge capacity throughput SOH of the power battery at the current moment.

[0092] S360 is executed after S340 .

[0093] S360: Calculate the second attenuation SOH.

[0094] S370 is executed after S320 .

[0095] S370: Calculate the third attenuation SOH.

[0096] S380 and S390 are executed before S310.

[0097] S380: Retrieve the last power-off time and record the current power-on time.

[0098] S390, determine whether a power-off signal is detected; if so, execute S391; if not, continue to execute S390.

[0099] S391. Record the power-off time.

[0100] S392 is executed after S380.

[0101] S392: Calculate the first attenuation SOH.

[0102] S393 is executed after S350 , S360 , S370 , and S392 .

[0103] S393 : Estimate the current SOH of the power battery according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH.

[0104] The technical solution provided by the embodiment of the present invention uses battery discharge capacity throughput, calendar life, high temperature and high SOC working time as SOH determining parameters, and considers the influencing factors of battery SOH in multiple dimensions to avoid a single parameter. Moreover, due to the multi-dimensional consideration of the influencing factors of battery SOH, the estimation accuracy of battery SOH is effectively improved and the estimation error is reduced. In addition, since the real-time acquisition of voltage, current and temperature is a basic function of BMS, this part can be designed as a standardized module, such as sensor interface, data filtering algorithm, etc., which can be directly reused in different types of batteries or products, avoiding the repeated development of hardware drivers and software acquisition logic, saving hardware development time and software debugging costs.

[0105] Figure 4 A schematic diagram of a power battery SOH estimation device provided by an embodiment of the present invention is shown in FIG. Figure 4 The device includes: an acquisition module 410, a calculation module 420 and an estimation module 430.

[0106] The acquisition module 410 is used to obtain the current voltage, current and temperature of the power battery, and record the first accumulated working time during which the current temperature is greater than or equal to a preset temperature.

[0107] The calculation module 420 is used to calculate the current cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH and the third attenuation SOH of the power battery according to the current voltage, the current and the temperature.

[0108] The estimation module 430 is configured to estimate the current SOH of the power battery according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH.

[0109] A power battery SOH estimation device provided by an embodiment of the present invention can execute a power battery SOH estimation method provided by any embodiment of the present invention, and has corresponding functional modules and beneficial effects of the execution method.

[0110] Figure 5 A schematic structural diagram of an electronic device for a power battery SOH estimation method provided in an embodiment of the present invention. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0111] like Figure 5 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., which is communicatively connected to the at least one processor 11. The memory stores a computer program that can be executed by the at least one processor. The processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 into the random access memory (RAM) 13. Various programs and data required for the operation of the electronic device 10 can also be stored in the RAM 13. The processor 11, ROM 12, and RAM 13 are connected to each other via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0112] Multiple components in the electronic device 10 are connected to the I / O interface 15, including an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a magnetic disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks.

[0113] The processor 11 can be any general-purpose and / or specialized processing component with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various specialized artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a method for a power battery SOH estimation device.

[0114] In some embodiments, the power battery SOH estimation method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the power battery SOH estimation method described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to execute the power battery SOH estimation method in any other appropriate manner (e.g., by means of firmware).

[0115] Various embodiments of the systems and techniques described herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system-on-chip systems (SOCs), programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that are executable and / or interpreted on a programmable system that includes at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0116] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the computer program is executed by the processor, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The computer program may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0117] In the context of the present invention, computer-readable storage media can be tangible media that can contain or store a computer program for use with an instruction execution system, device or equipment or used in combination with an instruction execution system, device or equipment. Computer-readable storage media can include but are not limited to electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, computer-readable storage media can be machine-readable signal media. More specific examples of machine-readable storage media can include electrical connections based on one or more lines, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0118] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0119] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0120] A computing system may include clients and servers. The clients and servers are typically remote from each other and typically interact via a communication network. This client-server relationship arises through computer programs running on the respective computers, creating a client-server relationship. The server may be a cloud server, also known as a cloud computing server or cloud host. This server is a hosting product within the cloud computing service ecosystem that addresses the management difficulties and limited scalability of traditional physical hosting and VPS services.

[0121] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved. This is not limited herein.

[0122] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A power battery SOH estimation method, characterized in that: include: Obtaining the current voltage, current, and temperature of the power battery, and recording the first accumulated operating time during which the current temperature is greater than or equal to a preset temperature; Calculating the cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH of the power battery at the current moment according to the current voltage, the current, and the current temperature; The current SOH of the power battery is estimated according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH.

2. The method according to claim 1, characterized in that Before obtaining the current voltage, current and temperature of the power battery, the method further includes: Retrieve the last power-off time and record the current power-on time.

3. The method according to claim 2, characterized in that Calculating the cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH of the power battery at the current moment according to the current voltage, the current, and the current temperature includes: Calculating the current state of charge (SOC) and the cumulative discharge capacity throughput of the power battery according to the current voltage and the current current, and recording a second cumulative operating time during which the current SOC is greater than or equal to a preset SOC; Calculating the cumulative discharge capacity throughput SOH of the power battery at the current moment according to the cumulative discharge capacity throughput at the current moment and the preset total capacity throughput; Calculating a first attenuation SOH according to the power-off hold time obtained from the last power-off time and the current power-on time, and a first preset attenuation coefficient; Calculating a second attenuation SOH according to the second accumulated working time and a second preset attenuation coefficient; A third attenuation SOH is calculated according to the first accumulated operating time and a third preset attenuation coefficient.

4. The method according to claim 1, wherein The estimating the current SOH of the power battery according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH includes: Use the following formula to estimate the current SOH of the power battery; SOH=100%-SOH cap -SOH calendar -SOH HighSOC -SOH HighT Where SOH cap is the cumulative capacity throughput SOH, SOH calendar is the first attenuation SOH, SOH HighSOC is the second attenuation SOH, SOH HighT It is the third attenuation SOH.

5. The method according to claim 1, wherein Before obtaining the current voltage, current and temperature of the power battery, the method further includes: Determine whether a power-off signal is detected; If yes, the power-off time is recorded; if no, the step of determining whether a power-off signal is detected is continued.

6. The method according to claim 3, characterized in that Calculating the cumulative discharge capacity throughput SOH of the power battery at the current moment according to the cumulative discharge capacity throughput at the current moment and the preset total capacity throughput includes: The following formula is used to calculate the cumulative discharge capacity throughput SOH of the power battery at the current moment; Where SOH cap is the cumulative discharge capacity throughput SOH of the power battery at the current moment, Cap(k) is the cumulative discharge capacity throughput from the first power-on to the current moment, and Cap(Total) is the preset total capacity throughput.

7. The method according to claim 3, characterized in that Calculating the first attenuation SOH according to the power-off hold time obtained from the last power-off time and the current power-on time, and the first preset attenuation coefficient includes: The first attenuation SOH is calculated using the following formula: SOH calendar =a*T1Sk1; where SOH calendar is the first attenuation SOH, a is a first preset attenuation coefficient, and T1Sk1 is the power-off hold time obtained according to the last power-off time and the current power-on time.

8. The method according to claim 3, characterized in that The calculating the second attenuation SOH according to the second accumulated working time and the second preset attenuation coefficient includes: The second attenuation SOH is calculated using the following formula: SOH HighSOC =b*T2Sk2; where SOH HighSOC is the second attenuation SOH, b is the second preset attenuation coefficient, and T2Sk2 is the second accumulated working time.

9. The method according to claim 3, characterized in that Calculating the third attenuation SOH according to the first accumulated working time and the third preset attenuation coefficient includes: The third attenuation SOH is calculated using the following formula: SOH HighT =c*T3Sk3; where SOH HighT is the third attenuation SOH, c is the third preset attenuation coefficient, and T3Sk3 is the first accumulated working time.

10. A power battery SOH estimation device, characterized in that: include: an acquisition module, the acquisition module being configured to acquire a current voltage, a current current, and a current temperature of the power battery, and record a first accumulated operating time during which the current temperature is greater than or equal to a preset temperature; a calculation module, configured to calculate the cumulative discharge capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH of the power battery at the current moment according to the current voltage, the current, and the current temperature; An estimation module is configured to estimate the current SOH of the power battery according to the accumulated capacity throughput SOH, the first attenuation SOH, the second attenuation SOH, and the third attenuation SOH.

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