Battery charge state estimation method, device, equipment and medium

Abstract

The invention discloses a battery charge state estimation method and device, equipment and a medium. The battery charge state estimation method comprises the following steps: acquiring temperature information, rated capacity, charge and discharge current information, initial battery charge state and open-circuit voltage of a battery; determining a capacity temperature compensation function corresponding to the temperature information according to the temperature information; determining the effective capacity of the battery according to the temperature information, the rated capacity and the capacity temperature compensation function; determining a first battery charge state according to the initial battery charge state, the charge and discharge current information and the effective capacity by using an ampere-hour integral method; determining a second battery state of charge according to the open-circuit voltage and the effective capacity by using an open-circuit voltage method; and determining an actual battery state of charge according to the first battery state of charge and the second battery state of charge. The actual state of charge of the battery is obtained by adopting the method for estimating the state of charge of the battery, so that the accuracy of estimating the state of charge of the battery is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery state of charge estimation method, device, equipment and medium. BACKGROUND

[0002] SOC (State of Charge) is the remaining capacity of the battery, also known as the state of charge, which is defined as the ratio of the remaining capacity to the rated capacity of the battery, usually expressed in percentage. Its value range is 0-1, when SOC = 0, it means the battery is completely discharged, and when SOC = 1, it means the battery is fully charged.

[0003] At present, the methods for calculating SOC include open circuit voltage method and ampere-hour integral method. The existing battery SOC estimation technology has the following defects: 1. Static capacity calibration: the traditional method relies on fixed nominal capacity and does not consider the dynamic influence of temperature on battery chemical activity, resulting in virtual high capacity in high temperature environment and sudden drop of capacity in low temperature environment (error can reach more than 30%). 2. Linear compensation limitation: most schemes use single linear temperature compensation, which cannot match the nonlinear decay characteristics of lead-acid / lithium battery at extreme temperature (such as capacity cutting at-20℃ due to electrolyte freezing). 3. Lack of data cooperation: ampere-hour integral method (coulomb counting) and open circuit voltage method (OCV) work independently, lack of dynamic calibration mechanism under temperature compensation, and cumulative error is significant. SUMMARY

[0004] The present application provides a battery state of charge estimation method, device, equipment and medium to solve the problems of existing battery state of charge estimation method being greatly affected by temperature, linear compensation having limitations, and ampere-hour integral method and open circuit voltage method working independently increasing the error of battery state of charge estimation.

[0005] In a first aspect, the present application provides a battery state of charge estimation method, which comprises:

[0006] Obtaining temperature information, rated capacity, charge and discharge current information, initial battery state of charge, static state information and open circuit voltage of the battery;

[0007] Determining a capacity temperature compensation function corresponding to the temperature information according to the temperature information;

[0008] Determining the effective capacity of the battery according to the temperature information, the rated capacity and the capacity temperature compensation function;

[0009] Determining a first battery state of charge according to the initial battery state of charge, the charge and discharge current information and the effective capacity by using ampere-hour integral method;

[0010] determining a second battery state of charge according to the temperature information, the open circuit voltage, and a temperature-compensated open circuit voltage-state of charge mapping table;

[0011] determining an actual battery state of charge according to the standing state information, the temperature information, the charging and discharging current information, the first battery state of charge, and the second battery state of charge.

[0012] Optionally, the temperature information corresponds to a capacity temperature compensation function according to the temperature information, and the capacity temperature compensation function comprises:

[0013] if the temperature information T satisfies 15℃ < T≤ 30℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated.

[0014] if the temperature information T satisfies 0℃ < T≤ 15℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(0.85+0.01×T).

[0015] if the temperature information T satisfies -20℃ < T≤ 0℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(0.85+T×11 / 800).

[0016] if the temperature information T satisfies T≤ -20℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×0.5.

[0017] if the temperature information T satisfies 30℃ < T≤ 40℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(1+0.01×(T-30)).

[0018] if the temperature information T satisfies T> 40℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×1.1.

[0019] wherein C_eff represents the effective capacity, and C_rated represents the rated capacity.

[0020] Optionally, the temperature information corresponds to a capacity temperature compensation function according to the temperature information, and the capacity temperature compensation function comprises:

[0021] if the temperature information T satisfies 28℃≤ T≤ 32℃, a Sigmoid function is used for dynamic interpolation.

[0022] Optionally, the first battery state of charge is determined according to the initial battery state of charge, the charging and discharging current information and the effective capacity by using ampere-hour integration method, and the method comprises the following steps:

[0023] The first battery state of charge is determined according to the initial battery state of charge, the charging and discharging current information, the effective capacity and the following corresponding relationship:

[0024] SOC_1=SOC_0+(∫Idt / C_eff)×100%;

[0025] Wherein, SOC_1 represents the first battery state of charge, SOC_0 represents the initial battery state of charge, I represents the charging and discharging current information, and C_eff represents the effective capacity.

[0026] Optionally, the initial battery state of charge of the battery is obtained, and the method comprises the following steps:

[0027] The initial open-circuit voltage and initial temperature information of the battery in a static state before charging and discharging are obtained;

[0028] The initial battery state of charge is determined according to the initial open-circuit voltage, the initial temperature information and the open-circuit voltage-state of charge mapping table after temperature compensation.

[0029] Optionally, the actual battery state of charge is determined according to the static state information, the temperature information, the charging and discharging current information, the first battery state of charge and the second battery state of charge, and the method comprises the following steps:

[0030] The first weight factor of the first battery state of charge and the second weight factor of the second battery state of charge are determined according to the static state information, the temperature information and the charging and discharging current information;

[0031] The actual battery state of charge is determined according to the first battery state of charge, the second battery state of charge, the first weight factor and the second weight factor.

[0032] Optionally, the first weight factor of the first battery state of charge and the second weight factor of the second battery state of charge are determined according to the static state information, the temperature information and the charging and discharging current information, and the method comprises the following steps:

[0033] If the battery is in a static state and the time S in the static state satisfies S>30min, the first weight factor α satisfies: α=0.1, and the second weight factor β satisfies: β=0.9;

[0034] If the charging and discharging current information I satisfies |I|>0.5xC_rated, or the temperature information satisfies AT>5℃ / min per minute, the first weight factor a satisfies a=0.8, and the second weight factor b satisfies b=0.2, wherein C_rated represents the rated capacity;

[0035] Otherwise, the first weight factor a satisfies a=0.4, and the second weight factor b satisfies b=0.6;

[0036] Wherein, 0≤a≤1, 0≤b≤1, and a+b=1;

[0037] Determining the actual battery state of charge according to the first battery state of charge, the second battery state of charge, the first weight factor, and the second weight factor, comprising:

[0038] Determining the actual battery state of charge according to the first battery state of charge, the second battery state of charge, the first weight factor, the second weight factor, and the following corresponding relationship:

[0039] SOC_real=a×SOC_1+b×SOC_2;

[0040] Wherein, SOC_real represents the actual battery state of charge, SOC_1 represents the first battery state of charge, and SOC_2 represents the second battery state of charge.

[0041] In a second aspect, an embodiment of the present application provides a battery state of charge estimation device for executing the battery state of charge estimation method as described in the first aspect, and the battery state of charge estimation device comprises:

[0042] A battery information acquisition unit is configured to acquire temperature information, a rated capacity, charging and discharging current information, an initial battery state of charge, static state information, and an open circuit voltage of a battery.

[0043] A temperature compensation unit is configured to determine a capacity temperature compensation function corresponding to the temperature information according to the temperature information.

[0044] A battery effective capacity determination unit is configured to determine an effective capacity of the battery according to the temperature information, the rated capacity, and the capacity temperature compensation function.

[0045] A first battery state of charge determination unit is configured to determine a first battery state of charge according to the initial battery state of charge, the charging and discharging current information, and the effective capacity by using an ampere-hour integration method.

[0046] a second battery state of charge determination unit configured to determine a second battery state of charge according to the temperature information, the open-circuit voltage, and a temperature-compensated open-circuit voltage-state of charge mapping table by using an open-circuit voltage method;

[0047] a real battery state of charge determination unit configured to determine a real battery state of charge according to the static state information, the temperature information, the charge-discharge current information, the first battery state of charge, and the second battery state of charge.

[0048] In a third aspect, an embodiment of the present application provides a battery state of charge estimation device, which comprises:

[0049] one or more processors;

[0050] a storage device configured to store one or more programs;

[0051] When the one or more programs are executed by the one or more processors, the one or more processors implement the battery state of charge estimation method according to the first aspect.

[0052] In a fourth aspect, an embodiment of the present application provides a storage medium having a computer program stored thereon, which, when executed by a processor, implements the battery state of charge estimation method according to the first aspect.

[0053] The technical solution of the embodiment of the present application determines the capacity temperature compensation function corresponding to the temperature information according to the temperature information first, then determines the effective capacity of the battery according to the temperature information, the rated capacity, and the capacity temperature compensation function, and then respectively obtains the first battery state of charge and the second battery state of charge after temperature compensation by using the ampere-hour integral method and the open-circuit voltage method, and finally determines the real battery state of charge according to the first battery state of charge and the second battery state of charge, thereby solving the problems that the existing battery state of charge estimation method is greatly affected by temperature, linear compensation has limitations, and the ampere-hour integral method and the open-circuit voltage method work independently to increase the battery state of charge estimation error, and being conducive to improving the accuracy of battery state of charge estimation.

[0054] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiments description. Obviously, the drawings in the following description only show some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative effort based on these drawings.

[0056] Figure 1 The flow chart of the battery state of charge estimation method provided by the embodiment of the present application;

[0057] Figure 2 The flow chart of another battery state of charge estimation method provided by the embodiment of the present application;

[0058] Figure 3 The structural schematic diagram of the battery state of charge estimation device provided by the embodiment of the present application;

[0059] Figure 4 The structural schematic diagram of the battery state of charge estimation device provided by the embodiment of the present application; DETAILED DESCRIPTION

[0060] In order to make the personnel in the technical field better understand the present application, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort should belong to the protection scope of the present application.

[0061] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily limit to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices. The terms "up", "down", "left", "right", etc. indicate the orientation or positional relationship shown in the drawings, and are only used to illustrate the relative positional relationship between the components or components, and do not particularly limit the specific installation orientation of the components or components.

[0062] Figure 1A flowchart of a battery state of charge estimation method provided by an embodiment of the present application is shown in FIG. 1. The battery state of charge estimation method in the embodiment of the present application is applicable to a situation where the battery state of charge needs to be estimated. The battery state of charge estimation method can be executed by a battery state of charge estimation device, which can be implemented by software and / or hardware and specifically configured in a battery state of charge estimation apparatus. Referring to FIG. 1, the battery state of charge estimation method comprises the following steps. Figure 1 The battery state of charge estimation method in the embodiment of the present application comprises the following steps.

[0063] In S110, temperature information, rated capacity, charge and discharge current information, initial battery state of charge, static state information and open circuit voltage of the battery are obtained.

[0064] For example, the battery state of charge estimation device in the embodiment of the present application can be communicatively connected with a temperature sensor arranged on the battery, and thus the temperature information of the battery can be obtained through the temperature sensor.

[0065] The rated capacity of the battery is pre-stored in a storage, and the battery state of charge estimation device in the embodiment of the present application can be communicatively connected with the storage, and thus the rated capacity can be obtained from the storage when needed.

[0066] The battery state of charge estimation device in the embodiment of the present application can also be communicatively connected with a current sensor arranged in or near the charge and discharge circuit of the battery, and thus the charge and discharge current information of the battery can be obtained through the current sensor. It should be noted that when the battery is charging, the obtained charge and discharge current information is the charging current, and the charging current is positive; when the battery is discharging, the obtained charge and discharge current information is the discharging current, and the discharging current is negative.

[0067] As a feasible implementation, the initial battery state of charge of the battery is obtained by: obtaining initial open circuit voltage and initial temperature information when the battery is in a static state before charging and discharging; and determining the initial battery state of charge according to the initial open circuit voltage, the initial temperature information and a temperature-compensated open circuit voltage-state of charge mapping table.

[0068] For example, the initial battery state of charge can be obtained by the open circuit voltage (OCV) method. Specifically, the battery state of charge estimation device in the embodiment of the present application can also be communicatively connected with a voltage sensor for obtaining the open circuit voltage of the battery. When the time when the battery is in a static state (not charging or discharging) exceeds a preset time, the polarization voltage will dissipate. The battery state of charge estimation device can obtain the open circuit voltage of the battery through the voltage sensor, and then determine the battery state of charge corresponding to the obtained open circuit voltage by querying the temperature-compensated open circuit voltage-state of charge mapping table pre-stored in the storage, and take the state of charge as the initial battery state of charge when the battery is powered on this time.

[0069] In another possible implementation, the battery state of charge at the last time of battery shutdown can also be used as the initial battery state of charge at the present time of power-on. Specifically, at the last time of normal shutdown, the battery state of charge estimation device in the embodiment of the present application can write the final battery state of charge into the storage. At the present time of power-on, the battery state of charge estimation device can directly read this value as the initial battery state of charge.

[0070] In a possible implementation, the battery state of charge estimation device in the embodiment of the present application can determine the static state information of the battery according to the obtained charge and discharge current information and the voltage information of the battery. Specifically, only when the charge and discharge current information is less than a preset minimum current threshold (for example, 0.005C), the voltage change rate is less than a preset minimum voltage change rate threshold (for example, 0.1 mV / min), and the charge and discharge current information and the voltage change rate satisfy the above conditions for more than a preset time threshold (for example, 30 min), it is determined that the battery is in a static state.

[0071] It should be noted that the open circuit voltage (OCV) refers to the terminal voltage of the battery when the internal electrochemical reaction reaches the equilibrium state after the battery is static (not charged or discharged) for a long enough time. The battery state of charge estimation device in the embodiment of the present application can obtain the open circuit voltage of the battery through the corresponding voltage sensor after determining that the battery is in a static state.

[0072] S120, determining a capacity temperature compensation function corresponding to the temperature information according to the temperature information.

[0073] It can be understood that the influence of temperature on the capacity of the battery is nonlinear, and the temperature information of the battery in different temperature ranges usually corresponds to different capacity temperature compensation functions. It should be noted that the capacity temperature compensation function in the embodiment of the present application refers to a function that can describe the relationship between the actual capacity of the battery and the temperature change.

[0074] As a feasible implementation, the capacity temperature compensation function corresponding to the temperature information is determined according to the temperature information, including: if the temperature information T satisfies 15℃ < T≤ 30℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated; if the temperature information T satisfies 0℃ < T≤ 15℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(0.85+0.01×T); if the temperature information T satisfies -20℃ < T≤ 0℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(0.85+T×11 / 800); if the temperature information T satisfies T≤ -20℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×0.5; if the temperature information T satisfies 30℃ < T≤ 40℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(1+0.01×(T-30)); if the temperature information T satisfies T> 40℃, the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×1.1; wherein, C_eff represents the effective capacity, and C_rated represents the rated capacity.

[0075] The T×11 / 800 is introduced instead of a fixed slope when the temperature of the battery is close to -20℃ (for example, the attenuation slope is increased from 0.6% to 0.8% when the temperature is -10℃), so that the change of the battery capacity is closer to the capacity drop characteristics of the lead-acid battery near the freezing point. When the temperature T of the battery is less than or equal to -20℃, the effective capacity of the battery is forced to be 50% of the rated capacity, and a protection mode is triggered, so that an extreme temperature failure protection mechanism is constructed, and the reliability of the battery system is improved.

[0076] The embodiment of the application constructs a six-segment temperature compensation function, and realizes dynamic calibration of the battery capacity in a full temperature range (-30℃~60℃).

[0077] Optionally, the capacity temperature compensation function corresponding to the temperature information is determined according to the temperature information, and the method further includes: if the temperature information T satisfies 28℃≤ T≤ 32℃, the Sigmoid function is used for dynamic interpolation.

[0078] It can be understood that the capacity of the battery in the interval of 28℃~32℃ is prone to jump, and the capacity is very sensitive to temperature change, so as to ensure the accuracy of the effective capacity, the embodiment of the application eliminates the jump by using a nonlinear boundary smoothing processing technology.

[0079] For example, the embodiment of the application can eliminate the capacity jump at 30℃±2℃ by using the Sigmoid function for dynamic interpolation in the interval of 28℃~32℃.

[0080] S130, determining the effective capacity of the battery according to the temperature information, the rated capacity and the capacity temperature compensation function.

[0081] For example, after determining the capacity temperature compensation function corresponding to the current battery temperature information, the current temperature information and the rated capacity of the battery can be substituted into the capacity temperature compensation function, and the effective capacity of the battery can be obtained.

[0082] S140, determining the first battery state of charge by using the ampere-hour integration method according to the initial battery state of charge, the charging and discharging current information and the effective capacity.

[0083] As a feasible implementation, the first battery state of charge is determined by using the ampere-hour integration method according to the initial battery state of charge, the charging and discharging current information and the effective capacity, comprising:

[0084] The first battery state of charge is determined according to the initial battery state of charge, the charging and discharging current information, the effective capacity and the following corresponding relationship: SOC_1=SOC_0+(∫Idt / C_eff)×100%, wherein SOC_1 represents the first battery state of charge, SOC_0 represents the initial battery state of charge, I represents the charging and discharging current information, and C_eff represents the effective capacity.

[0085] The embodiment of the application accumulates the charging and discharging electric quantity by taking the dynamic effective capacity C_eff compensated by temperature as the upper limit of the coulomb counter integration, replaces the fixed rated capacity, realizes real-time calibration of the effective capacity, and is beneficial to improving the accuracy of the first battery state of charge obtained by using the ampere-hour integration method.

[0086] Moreover, the embodiment of the application calibrates the coulomb counter cumulative error by using the open-circuit voltage-state of charge mapping table compensated by temperature (for example, the full-charge voltage at 40℃=13.25V) during the static period of the battery, realizes cooperation of the open-circuit voltage and temperature, and can further improve the accuracy of the first battery state of charge obtained by using the ampere-hour integration method.

[0087] S150, determining the second battery state of charge by using the open-circuit voltage method according to the temperature information, the open-circuit voltage, and the open-circuit voltage-state of charge mapping table compensated by temperature.

[0088] For example, when the battery is in a static state, the temperature information and the open-circuit voltage of the current battery can be obtained first, and then the open-circuit voltage-state of charge mapping table compensated by temperature pre-stored in the storage can be queried according to the temperature information and the open-circuit voltage to determine the second battery state of charge corresponding to the current temperature information and the open-circuit voltage.

[0089] S160, determine the actual battery state of charge according to the static state information, the temperature information, the charge and discharge current information, the first battery state of charge and the second battery state of charge.

[0090] The embodiment of the application fuses the results of two battery state of charge estimation methods, that is, the first battery state of charge obtained by using the ampere-hour integration method and the second battery state of charge obtained by using the open circuit voltage method. It can be understood that when the static state information, the temperature information and the charge and discharge current information of the battery are different, the influence degrees of the first battery state of charge and the second battery state of charge on the actual battery state of charge to be finally determined are different, and the relationships between the first battery state of charge, the second battery state of charge and the actual battery state of charge are also different.

[0091] The technical scheme of the embodiment of the application determines the capacity temperature compensation function corresponding to the temperature information according to the temperature information first, then determines the effective capacity of the battery according to the temperature information, the rated capacity and the capacity temperature compensation function, and then obtains the first battery state of charge and the second battery state of charge after temperature compensation by using the ampere-hour integration method and the open circuit voltage method respectively, and finally determines the actual battery state of charge according to the first battery state of charge and the second battery state of charge, thereby solving the problems that the existing battery state of charge estimation method is greatly affected by temperature, linear compensation has limitations, and the ampere-hour integration method and the open circuit voltage method work independently to increase the battery state of charge estimation error, and being conducive to improving the accuracy of battery state of charge estimation.

[0092] Figure 2 The flowchart of another battery state of charge estimation method provided by the embodiment of the application is shown in Figure 2 The embodiment shown in the figure details how to determine the actual battery state of charge according to the static state information, the temperature information, the charge and discharge current information, the first battery state of charge and the second battery state of charge, and the reference Figure 2 The battery state of charge estimation method in the embodiment of the application comprises:

[0093] S210, obtain the temperature information, the rated capacity, the charge and discharge current information, the initial battery state of charge, the static state information and the open circuit voltage of the battery.

[0094] S220, determine the capacity temperature compensation function corresponding to the temperature information according to the temperature information.

[0095] S230, determine the effective capacity of the battery according to the temperature information, the rated capacity and the capacity temperature compensation function.

[0096] S240, determine the first battery state of charge according to the initial battery state of charge, the charge and discharge current information and the effective capacity by using the ampere-hour integration method.

[0097] S250, determining the second battery state of charge according to the temperature information, the open circuit voltage, and the open circuit voltage-state of charge mapping table compensated by temperature.

[0098] S260, determining a first weight factor of the first battery state of charge and a second weight factor of the second battery state of charge according to the resting state information, the temperature information, and the charging and discharging current information.

[0099] As a feasible implementation, the determining of the first weight factor of the first battery state of charge and the second weight factor of the second battery state of charge according to the resting state information, the temperature information, and the charging and discharging current information comprises: if the battery is in the resting state and the time S in the resting state satisfies S>30 min, the first weight factor a satisfies: a=0.1, and the second weight factor b satisfies: b=0.9; if the charging and discharging current information I satisfies: |I|>0.5xC_rated, or the temperature information satisfies: AT>5℃ / min per minute, the first weight factor a satisfies: a=0.8, and the second weight factor b satisfies: b=0.2, wherein C_rated represents the rated capacity; otherwise (i.e. in other cases except the above two cases), the first weight factor a satisfies: a=0.4, and the second weight factor b satisfies: b=0.6; wherein 0≤a≤1, 0≤b≤1, and a+b=1.

[0100] S270, determining the actual battery state of charge according to the first battery state of charge, the second battery state of charge, the first weight factor, and the second weight factor.

[0101] As a feasible implementation, the determining of the actual battery state of charge according to the first battery state of charge, the second battery state of charge, the first weight factor, and the second weight factor comprises:

[0102] The actual battery state of charge is determined according to the first battery state of charge, the second battery state of charge, the first weight factor, the second weight factor, and the following corresponding relationship:

[0103] SOC_real=a×SOC_1+b×SOC_2, wherein SOC_real represents the actual battery state of charge, SOC_1 represents the first battery state of charge, and SOC_2 represents the second battery state of charge.

[0104] Based on the same inventive concept, the embodiment of the present application also provides a battery state of charge estimation device, Figure 3 A structural schematic diagram of the battery state of charge estimation device provided by the embodiment of the present application is shown in Figure 3 The battery state of charge estimation device in the embodiment of the present application comprises:

[0105] The battery information acquisition unit 310 is configured to acquire temperature information, rated capacity, charge-discharge current information, initial battery state of charge, standing state information, and open circuit voltage of the battery.

[0106] The temperature compensation unit 320 is configured to determine a capacity temperature compensation function corresponding to the temperature information according to the temperature information.

[0107] The battery effective capacity determination unit 330 is configured to determine the effective capacity of the battery according to the temperature information, the rated capacity, and the capacity temperature compensation function.

[0108] The first battery state of charge determination unit 340 is configured to determine the first battery state of charge according to the initial battery state of charge, the charge-discharge current information, and the effective capacity by using the ampere-hour integration method.

[0109] The second battery state of charge determination unit 350 is configured to determine the second battery state of charge according to the temperature information, the open circuit voltage, and the temperature-compensated open circuit voltage-state of charge mapping table by using the open circuit voltage method.

[0110] The actual battery state of charge determination unit 360 is configured to determine the actual battery state of charge according to the standing state information, the temperature information, the charge-discharge current information, the first battery state of charge, and the second battery state of charge.

[0111] The battery state of charge estimation device provided by the embodiments of the present application can execute the battery state of charge estimation method provided by any of the embodiments of the present application, and has the corresponding function modules and beneficial effects of the execution method.

[0112] Figure 4 A structural schematic diagram of a battery state of charge estimation device 400 that can be used to implement embodiments of the present application is shown, which is intended to represent various forms of digital computers, such as laptops, desktops, tablets, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The battery state of charge estimation device can also represent various forms of mobile devices, such as personal digital processors, cellular telephones, smart phones, wearable devices (such as headsets, glasses, watches, etc.), and other similar computing devices. The components shown here, their connections, and their functions, are meant to be examples only, and are not intended to limit the implementations of the present application described and / or claimed in this document.

[0113] As Figure 4As shown, the battery state of charge estimation device 400 includes at least one processor 410, and a memory, such as a read-only memory (ROM) 420, a random access memory (RAM) 430, etc., communicatively connected to the at least one processor 410, where the memory stores computer programs executable by the at least one processor. The processor 410 can perform various appropriate actions and processes according to the computer programs stored in the read-only memory (ROM) 420 or loaded from the storage unit 480 into the random access memory (RAM) 430. Various programs and data required for the operation of the battery state of charge estimation device 400 can also be stored in the RAM 430. The processor 410, the ROM 420, and the RAM 430 are connected to each other through a bus 440. An input / output (I / O) interface 450 is also connected to the bus 440.

[0114] Various components in the battery state of charge estimation device 400 are connected to the I / O interface 450, including an input unit 460, such as a keyboard, a mouse, etc., an output unit 470, such as various types of displays, a speaker, etc., a storage unit 480, such as a magnetic disk, an optical disk, etc., and a communication unit 490, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 490 allows the battery state of charge estimation device 400 to exchange information / data with other devices through a computer network, such as the Internet, and / or various telecommunication networks.

[0115] The processor 410 can be various general and / or special purpose processing components with processing and computing capabilities. Some examples of the processor 410 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 410 performs various methods and processes described above, such as the battery state of charge estimation method.

[0116] In some embodiments, the battery state of charge estimation method can be implemented as a computer program tangibly embodied in a computer readable storage medium, such as the storage unit 480. In some embodiments, part or all of the computer program can be loaded and / or installed onto the battery state of charge estimation device 400 via the ROM 420 and / or the communication unit 490. When the computer program is loaded onto the RAM 430 and executed by the processor 410, one or more steps of the battery state of charge estimation method described above can be performed. Alternatively, in other embodiments, the processor 410 can be configured to perform the battery state of charge estimation method by any other appropriate means, such as by means of firmware.

[0117] The various embodiments of the systems and techniques described above can be implemented in digital electronic circuitry, integrated circuitry, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on a chip (SOC), a load programmable logic device (CPLD), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include implementation in one or more computer programs that are executable and / or interpretable on a programmable system including at least one programmable processor, which can be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0118] Computer programs used to implement the processes of the application can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the computer program

[0119] In the context of the present application, a computer-readable storage medium can be a tangible medium that can contain or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. The computer-readable storage medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium can be a machine-readable signal medium. More specific examples of the machine-readable storage medium will include one or more lines of a program of instructions in a transitory signal, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0120] To provide for interaction with a user, the systems and techniques described here can be implemented on a battery state of charge estimation 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 a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the battery state of charge estimation device. Other kinds of devices can be used to provide for interaction with a user as well; for example, 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, speech, or tactile input.

[0121] The systems and techniques described here can be implemented in a computing system that includes a back end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front end component (e.g., a user computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such back end, middleware, 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), blockchain network, and the Internet.

[0122] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server is generally remote and in

[0123] It should be understood that the steps shown in the various forms above can be reordered, added to, or removed. For example, the steps described in the present disclosure can be performed in parallel, in series, or in a different order, without limitation, as long as the desired results of the present disclosure are achieved.

[0124] The above detailed description does not limit the scope of the application. Various modifications, combinations, sub-combinations and alternatives can be made to the detailed description. Any modification, equivalent replacement and improvement etc. made within the spirit and principle of the application shall be included in the scope of the application.

Claims

1. A method for estimating the state of charge of a battery, characterized in that, The battery state-of-charge estimation method includes: Acquire battery temperature information, rated capacity, charge / discharge current information, initial battery state of charge, resting state information, and open-circuit voltage; Determine the capacity temperature compensation function corresponding to the temperature information based on the temperature information; The effective capacity of the battery is determined based on the temperature information, the rated capacity, and the capacity-temperature compensation function. The first battery state of charge is determined using the ampere-hour integration method based on the initial battery state of charge, the charge / discharge current information, and the effective capacity. The state of charge of the second battery is determined using the open-circuit voltage method, based on the temperature information, the open-circuit voltage, and the temperature-compensated open-circuit voltage-state-of-charge mapping table. The actual battery state of charge is determined based on the static state information, the temperature information, the charge / discharge current information, the first battery state of charge, and the second battery state of charge.

2. The battery state of charge estimation method according to claim 1, characterized in that, Determining the capacity temperature compensation function corresponding to the temperature information based on the temperature information includes: If the temperature information T satisfies: 15℃<T≤30℃, then the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated; If the temperature information T satisfies: 0℃<T≤15℃, then the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(0.85+0.01×T) If the temperature information T satisfies: -20℃<T≤0℃, then the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(0.85+T×11 / 800) If the temperature information T satisfies: T≤-20℃, then the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×0.5; If the temperature information T satisfies: 30℃<T≤40℃, then the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff=C_rated×(1+0.01×(T-30)). If the temperature information T satisfies: T > 40℃, then the capacity temperature compensation function corresponding to the temperature information T is as follows: C_eff = C_rated × 1.1; Wherein, C_eff represents the effective capacity, and C_rated represents the rated capacity.

3. The battery state-of-charge estimation method according to claim 2, characterized in that, Determining the capacity temperature compensation function corresponding to the temperature information based on the temperature information also includes: If the temperature information T satisfies: 28℃≤T≤32℃, then the Sigmoid function is used for dynamic interpolation.

4. The battery state of charge estimation method according to claim 1, characterized in that, The first battery state of charge is determined using the ampere-hour integration method based on the initial battery state of charge, the charge / discharge current information, and the effective capacity, including: The first battery state of charge is determined based on the initial battery state of charge, the charge / discharge current information, the effective capacity, and the following correspondence: SOC_1=SOC_0+(∫Idt / C_eff)×100%; Wherein, SOC_1 represents the first battery state of charge, SOC_0 represents the initial battery state of charge, I represents the charge / discharge current information, and C_eff represents the effective capacity.

5. The battery state of charge estimation method according to claim 1, characterized in that, Obtain the initial state of charge of the battery, including: Obtain the initial open-circuit voltage and initial temperature information of the battery when it is in a static state before charging and discharging; The initial battery state of charge is determined based on the initial open-circuit voltage, the initial temperature information, and the temperature-compensated open-circuit voltage-state-of-charge mapping table.

6. The battery state of charge estimation method according to claim 1, characterized in that, Determining the actual battery state of charge (SOC) based on the resting state information, the temperature information, the charge / discharge current information, the first battery SOC, and the second battery SOC includes: The first weighting factor of the first battery state of charge and the second weighting factor of the second battery state of charge are determined based on the static state information, the temperature information and the charge / discharge current information. The actual battery state of charge is determined based on the first battery state of charge, the second battery state of charge, the first weighting factor, and the second weighting factor.

7. The battery state of charge estimation method according to claim 1, characterized in that, Determining a first weighting factor for the state of charge of the first battery and a second weighting factor for the state of charge of the second battery based on the static state information, the temperature information, and the charge / discharge current information includes: If the battery is in a static state and the static state time S satisfies S>30min, then the first weighting factor α satisfies: α=0.1, and the second weighting factor β satisfies: β=0.9; If the charging / discharging current information I satisfies: |I|>0.5×C_rated, or the temperature information change per minute ΔT satisfies: ΔT>5℃ / min, then the first weighting factor α satisfies: α=0.8, the second weighting factor β satisfies: β=0.2, and C_rated represents the rated capacity; Otherwise, the first weighting factor α satisfies: α=0.4, and the second weighting factor β satisfies: β=0.6; Where 0≤α≤1, 0≤β≤1, and α+β=1; Determining the actual battery state of charge (SBC) based on the first battery SBC, the second battery SBC, the first weighting factor, and the second weighting factor includes: The actual battery state of charge (SBC) is determined based on the first battery SBC, the second battery SBC, the first weighting factor, the second weighting factor, and the following correspondence: SOC_real=α×SOC_1+β×SOC_2; Wherein, SOC_real represents the actual state of charge of the battery, SOC_1 represents the first state of charge of the battery, and SOC_2 represents the second state of charge of the battery.

8. A battery state-of-charge estimation apparatus, used to perform the battery state-of-charge estimation method as described in any one of claims 1-7, characterized in that, The battery state-of-charge estimation device includes: The battery information acquisition unit is used to acquire battery temperature information, rated capacity, charge and discharge current information, initial battery state of charge, resting state information, and open circuit voltage. A temperature compensation unit is used to determine the capacity temperature compensation function corresponding to the temperature information based on the temperature information. A battery effective capacity determination unit is used to determine the effective capacity of the battery based on the temperature information, the rated capacity, and the capacity-temperature compensation function. The first battery state of charge determination unit is used to determine the first battery state of charge using the ampere-hour integration method based on the initial battery state of charge, the charging and discharging current information and the effective capacity. The second battery state of charge determination unit is used to determine the state of charge of the second battery by using the open-circuit voltage method, based on the temperature information, the open-circuit voltage, and the temperature-compensated open-circuit voltage-state of charge mapping table. The actual battery state of charge determination unit is used to determine the actual battery state of charge based on the static state information, the temperature information, the charge / discharge current information, the first battery state of charge, and the second battery state of charge.

9. A battery state of charge estimation device, characterized in that, The battery state-of-charge estimation device includes: One or more processors; Storage device for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the battery state-of-charge estimation method as described in any one of claims 1-7.

10. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the battery state-of-charge estimation method as described in any one of claims 1-7.

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