Method and apparatus for determining battery soc based on battery model

Abstract

The application relates to a battery SOC determination method and device based on a battery model, which comprises the following steps: acquiring a battery model corresponding to a battery, a numerical value of a parameter of the battery model, and a mapping relationship between an open-circuit voltage of the battery and an SOC; acquiring a real-time voltage of the battery measured at a current moment; and determining an SOC at a next moment according to the numerical value of the parameter, the mapping relationship between the open-circuit voltage of the battery and the SOC, a measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment. The application realizes observation of battery power based on a battery model, and can realize accurate estimation of the SOC of the battery under a changing load only by measuring the real-time voltage of the battery.

Description

Technical Field

[0001] This application relates to the field of battery management technology, and in particular to a method and apparatus for determining battery SOC based on a battery model. Background Technology

[0002] Determining the State of Charge (SOC) is one of the fundamental functions of a Battery Management System (BMS). The SOC provides a crucial parameter for the operation of end products containing the battery (e.g., laptops, electric vehicles).

[0003] Currently, achieving high-precision battery power management typically requires an additional power management chip to calculate the remaining battery power. In existing technologies, a common approach is to use an ADC (Analog-to-Digital Converter) as the voltage measurement unit, and calculate the remaining power using a voltage-to-power mapping table.

[0004] However, under dynamic loads, the sampling accuracy of the ADC is limited and cannot reach a very high level. Moreover, for changes in current load, especially in systems with high-frequency changes, the battery's internal resistance and capacitance effects can cause sudden and gradual changes in the battery voltage measurement, which can interfere with real-time power conversion and make it impossible to accurately determine the remaining power through the measured voltage. Summary of the Invention

[0005] To address the problems of existing technologies, this application provides a battery SOC determination scheme based on a battery model. This scheme is based on a battery model corresponding to the battery, and obtains the relationship between the SOC at the next time step and the parameters of the battery model, the SOC at the current time step, and the real-time voltage of the battery at the current time step through the battery model. Finally, the SOC at the next time step is determined by the parameters of the battery model step, the SOC at the current time step, and the real-time voltage of the battery at the current time step, thereby determining the SOC of the battery at each time step.

[0006] According to a first aspect of this application, a method for determining battery SOC based on a battery model is provided, characterized in that it includes:

[0007] Obtain the battery model corresponding to the battery, the numerical values ​​of the parameters of the battery model, and the mapping relationship between the battery open-circuit voltage and SOC;

[0008] Obtain the real-time voltage of the battery as measured at the current moment; and

[0009] Based on the values ​​of the parameters, the mapping relationship between the battery open-circuit voltage and SOC, the measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment, the SOC at the next moment is determined.

[0010] According to a second aspect of this application, a device for determining battery SOC based on a battery model is provided, characterized in that it comprises:

[0011] The first acquisition module is used to acquire the battery model corresponding to the battery, the value of the parameters of the battery model, and the mapping relationship between the battery open-circuit voltage and SOC.

[0012] The second acquisition module is used to acquire the real-time voltage of the battery measured at the current moment; and

[0013] The first determining module is used to determine the SOC at the next moment based on the value of the parameter, the mapping relationship between the battery open-circuit voltage and SOC, the measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment.

[0014] According to a third aspect of this application, a chip is provided, characterized in that the chip includes a processor, the processor being configured to perform the determination method as described in the first aspect; or,

[0015] The chip includes the determining device as described in the second aspect.

[0016] According to a fourth aspect of this application, a battery management system is provided for performing the determination method as described in the first aspect.

[0017] According to a fifth aspect of this application, an electronic device is provided, comprising:

[0018] Processor; and

[0019] A memory storing computer instructions that, when executed by the processor, cause the processor to perform the method described in the first aspect.

[0020] According to a sixth aspect of this application, a non-transitory computer storage medium is provided, which stores a computer program that, when executed by a plurality of processors, causes the processors to perform the method described in the first aspect.

[0021] According to the battery model-based method and apparatus for determining battery SOC provided in this application, a battery model corresponding to the battery is determined according to the specific requirements of the SOC determination process, and the relevant parameters and values ​​of the battery model are obtained. After determining the relationship between the battery SOC and relevant information (such as the parameters of the battery model and the measured real-time voltage), the battery SOC is determined based on the relevant information. Thus, since, except for the real-time voltage, the parameters of the battery model and other relevant information are fixed or known at the current moment during the battery SOC determination process, only the real-time voltage of the battery at the current moment needs to be obtained to determine the SOC value at the next moment based on the relationship between the battery SOC and relevant information. This application enables the observation of battery capacity based on a battery model; by simply measuring the real-time voltage of the battery, an accurate estimation of the battery SOC under varying loads can be achieved. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings, without exceeding the scope of protection claimed by this application.

[0023] Figure 1 This is a flowchart of a method for determining battery SOC based on a battery model according to an embodiment of this application.

[0024] Figure 2 This is a schematic diagram of a simplified battery model.

[0025] Figure 3 This is a schematic diagram of a first-order battery model.

[0026] Figure 4 This is a schematic diagram of a second-order battery model.

[0027] Figure 5 This is a flowchart of a method for determining battery SOC based on a battery model according to another embodiment of this application.

[0028] Figure 6 This is a flowchart of a method for determining battery SOC based on a battery model according to yet another embodiment of this application.

[0029] Figure 7 This is a flowchart of a method for determining battery SOC based on a battery model according to another embodiment of this application.

[0030] Figure 8 This is a schematic diagram of a battery SOC determination device based on a battery model according to an embodiment of this application.

[0031] Figure 9 This is a schematic diagram of a battery SOC determination device based on a battery model according to another embodiment of this application.

[0032] Figure 10 This is a schematic diagram of a battery SOC determination device based on a battery model according to yet another embodiment of this application.

[0033] Figure 11 This is a schematic diagram of a battery SOC determination device based on a battery model according to another embodiment of this application.

[0034] Figure 12 This is a structural diagram of an electronic device provided in this application. Detailed Implementation

[0035] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] According to one aspect of this application, a method for determining battery SOC based on a battery model is provided. Figure 1 This is a flowchart of a method for determining battery SOC based on a battery model according to an embodiment of this application. Figure 1 As shown, the method includes the following steps.

[0037] Step S101: Obtain the battery model corresponding to the battery, the numerical values ​​of the parameters of the battery model, and the mapping relationship between the battery open-circuit voltage and SOC.

[0038] According to some embodiments, the battery first needs to be modeled, that is, the corresponding battery model needs to be determined for the battery. Figure 2 , Figure 3 and Figure 4 Schematic diagrams of a simplified battery model, a first-order battery model, and a second-order battery model are shown respectively. Those skilled in the art can choose a simpler battery model according to actual needs, such as... Figure 2 The model shown, or you can choose a more complex battery model, such as Figure 3 The model shown is an example. For instance, if the system containing the battery has high timeliness requirements during operation, a more complex battery model can be used, while if the load change frequency of the system containing the battery is low, a simpler battery model can be selected.

[0039] According to some embodiments, after determining the battery model, the parameters of the battery model can be obtained, for example, Figure 2The parameters of the model shown include resistance R0. Figure 3 The parameters of the model shown include resistance R0, resistance Rp, and capacitance Cp. Figure 4 The parameters of the model shown include resistors R0, R1, and R2, and capacitors C1 and C2. The specific values ​​of these battery model parameters vary depending on the battery. These values ​​can be obtained in two ways: first, directly from the battery manufacturer; and second, by modeling the battery using simulation software such as MATLAB or SCILAB, and then adjusting the model to match the battery test results through parameter testing. For the second method, the battery's internal resistance, internal capacitance, total capacity, and its relationship to temperature or aging can be modeled, verified, and state equations constructed to predict internal parameters, thus achieving a more accurate testing scheme. When the parameter values ​​obtained through the first method differ from those obtained through the second method, the values ​​obtained through the second method are usually considered more accurate.

[0040] According to some embodiments, the mapping relationship between battery open-circuit voltage and SOC can also be obtained, and a mapping table between battery open-circuit voltage and battery capacity can be established. The mapping relationship between battery open-circuit voltage and SOC can be obtained directly from the battery manufacturer or through measurement.

[0041] Step S102: Obtain the real-time voltage of the battery measured at the current moment.

[0042] According to some embodiments, the real-time voltage of the battery is measured using a battery voltage sensor, such as an ADC, to obtain the real-time voltage value.

[0043] Step S103: Determine the SOC at the next moment based on the values ​​of the parameters, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment.

[0044] Before determining the SOC at the next moment based on the parameter values, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment, it is necessary to establish the relationship between the SOC at the next moment and the parameter values, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment. This relationship varies depending on the battery model selected.

[0045] by Figure 2 Taking the battery model shown as an example. Figure 2 In the equation (1), the open-circuit voltage is calculated as follows:

[0046] SOC(t)=f(U oc(t)) (1)

[0047] Among them, U oc (t) represents the battery open-circuit voltage, U l I(t) represents the real-time voltage of the battery, and I(t) represents the current.

[0048] According to the definition of battery capacity, the battery SOC is calculated as shown in equation (2):

[0049] U oc (t)=U l (t)-R0·I(t) (2)

[0050] Where SOC(t) represents the SOC of the battery at time t, t0 represents the SOC of the battery at time t0, and Qn represents the total battery capacity.

[0051] In addition, the mapping relationship between the battery open-circuit voltage and the battery SOC can be shown in equations (3) and (4):

[0052]

[0053] f -1 (SOC(t))=U oc (t) (4)

[0054] After transformation, we can obtain the state equation shown in equation (5):

[0055]

[0056] Discretizing equation (5) yields equation (6):

[0057]

[0058] Among them, t k and t k+1 Let k and k+1 represent time k and time k, respectively.

[0059] Equation (6) shows that the SOC at the next moment can be determined by the parameter values, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment. In this way, the battery SOC at each moment can be obtained through continuous iteration.

[0060] by Figure 3 Taking the battery model shown as an example. Figure 3 In the equation (7), the open-circuit voltage is calculated as follows:

[0061] U oc (t)=U k (t)-R0·I(t)-Up (t) (7)

[0062] Among them, U oc (t) represents the battery open-circuit voltage, U l Up(t) represents the real-time voltage of the battery, Up(t) represents the voltage across the capacitor, which is the internal state value of the battery model, and I(t) represents the current.

[0063] The internal state values ​​of the battery model are shown in equation (8):

[0064]

[0065] The calculation of battery SOC and the mapping relationship between battery open-circuit voltage and battery SOC are shown in equations (2), (3) and (4), respectively.

[0066] After transformation, we can obtain the state equations shown in equations (9) and (10):

[0067]

[0068]

[0069] Discretizing equations (9) and (10) yields equations (11) and (12):

[0070]

[0071]

[0072] Equations (11) and (12) show that the SOC at the next moment can be determined by the parameter values, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC and internal state values ​​of the battery model at the current moment. In this way, the battery SOC at each moment can be obtained by continuous iteration.

[0073] by Figure 4 Taking the battery model shown as an example. Figure 4 In the equation (13), the open-circuit voltage is calculated as follows:

[0074] U oc (t)=U L (t)-R0·I(t)-U1(t)-U2(t) (13)

[0075] Among them, U oc (t) represents the battery open-circuit voltage, U LU(t) represents the real-time voltage of the battery, U1(t) and U2(t) represent the internal state values ​​of the battery model at the terminals of capacitors C1 and C2, respectively, and I(t) represents the current.

[0076] The internal state values ​​of the battery model at both ends of capacitors C1 and C2 are shown in equations (14) and (15):

[0077]

[0078]

[0079] The calculation of battery SOC and the mapping relationship between battery open-circuit voltage and battery SOC are shown in equations (2), (3) and (4), respectively.

[0080] After transformation, we can obtain the state equations shown in equations (16), (17), and (18):

[0081]

[0082]

[0083]

[0084] Discretizing equations (16), (17), and (18) yields equations (19), (20), and (21):

[0085]

[0086]

[0087]

[0088] Equations (19), (20), and (21) show that the SOC at the next moment can be determined by the parameter values, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC and internal state values ​​of the battery model at the current moment. In this way, the battery SOC at each moment can be obtained through continuous iteration.

[0089] so, Figure 1 Step S103 may specifically include: determining the SOC at the next moment based on the value of the parameter, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, the SOC at the current moment, and the internal state value of the battery model at the current moment.

[0090] The internal state values ​​of the battery model are also obtained through continuous iterative processing, such as... Figure 3and Figure 4 In the battery model shown, the internal state value of the battery model at the next moment is related to the value of the battery model parameters, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the internal state value of the battery model at the current moment.

[0091] In this way, it also provides Figure 5 The method for determining battery SOC based on a battery model is shown. (Compared to...) Figure 1 Compared to steps S501 to S503, Figure 1 Steps S101 to S103 shown are the same, except that... Figure 5 The method shown may also include:

[0092] Step S504: Determine the internal state value for the next moment based on the values ​​of the parameters, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the internal state value of the battery model at the current moment.

[0093] According to some embodiments, in order to determine the SOC at each time point through iteration, it is necessary to know the time interval for measuring the real-time voltage and the SOC at the start of the measurement, i.e., the SOC at the initial time.

[0094] First, the measurement time interval can be set according to actual needs. In some embodiments, different time intervals can be selected to measure the battery's real-time voltage based on the frequency of load changes. Generally, the faster the battery load changes, the shorter the time interval should be; the sampling frequency for real-time voltage is usually more than twice the load change frequency. For example, if the load change frequency is 2Hz, then the real-time voltage should be sampled at least 4 times per second, typically more than 20 times, with a corresponding time interval of no more than 0.25 seconds. This allows low-power devices to select an extremely low real-time voltage sampling frequency in standby mode, reducing device power consumption.

[0095] In this way, it also provides Figure 6 The method for determining battery SOC based on a battery model is shown. (Compared to...) Figure 5 Compared to steps S601 to S604, Figure 5 Steps S501 to S504 shown are the same, the difference is that Figure 6 The method shown may also include:

[0096] Step S605: Determine the measurement time interval based on the frequency of load change of the battery.

[0097] Secondly, the initial State of Charge (SOC) can be determined by obtaining the battery's initial open-circuit voltage and then using the mapping relationship between the battery's open-circuit voltage and SOC. There are two ways to obtain the initial open-circuit voltage. The first method is when the current is very small (e.g., when the connected load is in standby mode with very low power consumption), less than a preset value. In this case, the voltage drop within the battery is very small and can be ignored; the measured real-time voltage at this point is taken as the battery's initial open-circuit voltage. The second method is when the system containing the battery is stable, the current value is stable and known, and the battery's voltage drop can be obtained based on the current and the battery's internal resistance. Combined with the measured real-time voltage, the battery's initial open-circuit voltage can be obtained.

[0098] According to other embodiments, in order to determine the SOC and internal state values ​​of the battery model at each time point through iteration, it is also necessary to know the internal state values ​​of the battery model at the initial time. The initial open-circuit voltage value of the battery can be obtained in two ways. In the first way, the internal state value of the battery model at the initial time can be set to 0. In the second way, with the current value stable, the internal state value of the battery model at the initial time is calculated based on the current value and the resistance corresponding to the capacitor in the battery model.

[0099] In this way, it also provides Figure 7 The method for determining battery SOC based on a battery model is shown. (Compared to...) Figure 6 In comparison, steps S701 to S705 are the same as... Figure 6 Steps S601 to S605 shown are the same, except that... Figure 7 The method shown may also include:

[0100] Step S706: Obtain the open-circuit voltage value of the battery at the initial moment;

[0101] Step S707: Obtain the SOC at the initial time based on the open-circuit voltage value at the initial time and the mapping relationship between the battery open-circuit voltage and SOC.

[0102] Furthermore, step S706 specifically includes:

[0103] If the battery current is less than a preset value, the measured real-time voltage is determined as the open-circuit voltage value of the battery at the initial moment; or

[0104] When the battery is in a stable state, the open-circuit voltage value of the battery at the initial moment is determined based on the current in the stable state and the measured real-time voltage.

[0105] The battery SOC determination scheme based on the battery model presented in this application is applicable not only to the battery discharge process, but also to the battery charging process, and even to the process of charging and discharging simultaneously. Moreover, this application adopts an iterative approach, using the state information of the previous moment to determine the current state information. This not only improves the accuracy of determining the battery capacity, but also, even if there are errors in the battery measurement (including errors in the initial state and errors in the real-time voltage measured later), these errors can be corrected through continuous iteration, resulting in a continuous reduction in the calculated error and more accurate battery capacity values ​​obtained subsequently.

[0106] According to another aspect of this application, a device method for battery SOC based on a battery model is provided. Figure 8 This is an applicable diagram of a battery SOC determination device based on a battery model according to an embodiment of this application. Figure 8 As shown, the device includes the following modules.

[0107] The first acquisition module 801 is used to acquire the battery model corresponding to the battery, the numerical values ​​of the parameters of the battery model, and the mapping relationship between the battery open-circuit voltage and SOC.

[0108] According to some embodiments, the battery first needs to be modeled, that is, the corresponding battery model needs to be determined for the battery. Figure 2 , Figure 3 and Figure 4 Schematic diagrams of a simplified battery model, a first-order battery model, and a second-order battery model are shown respectively. Those skilled in the art can choose a simpler battery model according to actual needs, such as... Figure 2 The model shown, or you can choose a more complex battery model, such as Figure 3 The model shown is an example. For instance, if the system containing the battery has high timeliness requirements during operation, a more complex battery model can be used, while if the load change frequency of the system containing the battery is low, a simpler battery model can be selected.

[0109] According to some embodiments, after determining the battery model, the parameters of the battery model can be obtained, for example, Figure 2 The parameters of the model shown include resistance R0. Figure 3 The parameters of the model shown include resistance R0, resistance Rp, and capacitance Cp. Figure 4The parameters of the model shown include resistors R0, R1, and R2, and capacitors C1 and C2. The specific values ​​of these battery model parameters vary depending on the battery. These values ​​can be obtained in two ways: first, directly from the battery manufacturer; and second, by modeling the battery using simulation software such as MATLAB or SCILAB, and then adjusting the model to match the battery test results through parameter testing. For the second method, the battery's internal resistance, internal capacitance, total capacity, and its relationship to temperature or aging can be modeled, verified, and state equations constructed to predict internal parameters, thus achieving a more accurate testing scheme. When the parameter values ​​obtained through the first method differ from those obtained through the second method, the values ​​obtained through the second method are usually considered more accurate.

[0110] According to some embodiments, the mapping relationship between battery open-circuit voltage and SOC can also be obtained, and a mapping table between battery open-circuit voltage and battery capacity can be established. The mapping relationship between battery open-circuit voltage and SOC can be obtained directly from the battery manufacturer or through measurement.

[0111] The second acquisition module 802 is used to acquire the real-time voltage of the battery measured at the current moment.

[0112] According to some embodiments, the real-time voltage of the battery is measured using a battery voltage sensor, such as an ADC, to obtain the real-time voltage value.

[0113] The first determining module 803 is used to determine the SOC at the next moment based on the value of the parameter, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment.

[0114] Before determining the SOC at the next moment based on the parameter values, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment, it is necessary to establish the relationship between the SOC at the next moment and the parameter values, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment. This relationship varies depending on the selected battery model.

[0115] according to Figure 3 and Figure 4 Battery model, Figure 8 The determination module 803 can be used to: determine the SOC at the next moment based on the value of the parameter, the mapping relationship between the battery open circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, the SOC at the current moment, and the internal state value of the battery model at the current moment.

[0116] The internal state values ​​of the battery model are also obtained through continuous iterative processing, such as... Figure 3 and Figure 4 In the battery model shown, the internal state value of the battery model at the next moment is related to the value of the battery model parameters, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the internal state value of the battery model at the current moment.

[0117] In this way, it also provides Figure 9 The apparatus shown is for determining the battery's state of charge (SOC) based on a battery model. Figure 8 In comparison, modules 901 to 903 and Figure 8 Modules 801 to 803 shown are the same, the difference being that... Figure 9 The apparatus shown may also include:

[0118] The second determining module 904 is used to determine the internal state value at the next moment based on the value of the parameter, the mapping relationship between the battery open-circuit voltage and SOC, the set measurement time interval, the real-time voltage at the current moment, and the internal state value of the battery model at the current moment.

[0119] According to some embodiments, in order to determine the SOC at each time point through iteration, it is necessary to know the time interval for measuring the real-time voltage and the SOC at the start of the measurement, i.e., the SOC at the initial time.

[0120] First, the measurement time interval can be set according to actual needs. In some embodiments, different time intervals can be selected to measure the battery's real-time voltage based on the frequency of load changes. Generally, the faster the battery load changes, the shorter the time interval should be; the sampling frequency for real-time voltage is usually more than twice the load change frequency. For example, if the load change frequency is 2Hz, then the real-time voltage should be sampled at least 4 times per second, typically more than 20 times, with a corresponding time interval of no more than 0.25 seconds. This allows low-power devices to select an extremely low real-time voltage sampling frequency in standby mode, reducing device power consumption.

[0121] In this way, it also provides Figure 10 The apparatus shown is for determining the battery's state of charge (SOC) based on a battery model. Figure 9 In comparison, modules 1001 to 1004 and Figure 9 Modules 901 to 904 shown are the same, the difference being that... Figure 10 The apparatus shown may also include:

[0122] The third determining module 1005 is used to determine the measurement time interval based on the frequency of load change of the battery.

[0123] Secondly, the initial State of Charge (SOC) can be determined by obtaining the battery's initial open-circuit voltage and then using the mapping relationship between the battery's open-circuit voltage and SOC. There are two ways to obtain the initial open-circuit voltage. The first method is when the current is very small (e.g., when the connected load is in standby mode with very low power consumption), less than a preset value. In this case, the voltage drop within the battery is very small and can be ignored; the measured real-time voltage at this point is taken as the battery's initial open-circuit voltage. The second method is when the system containing the battery is stable, the current value is stable and known, and the battery's voltage drop can be obtained based on the current and the battery's internal resistance. Combined with the measured real-time voltage, the battery's initial open-circuit voltage can be obtained.

[0124] According to other embodiments, in order to determine the SOC and internal state values ​​of the battery model at each time point through iteration, it is also necessary to know the internal state values ​​of the battery model at the initial time. The initial open-circuit voltage value of the battery can be obtained in two ways. In the first way, the internal state value of the battery model at the initial time can be set to 0. In the second way, with the current value stable, the internal state value of the battery model at the initial time is calculated based on the current value and the resistance corresponding to the capacitor in the battery model.

[0125] In this way, it also provides Figure 11 The apparatus shown is for determining the battery's state of charge (SOC) based on a battery model. Figure 10 In comparison, modules 1101 to 1105 and Figure 10 Modules 1001 to 1005 shown are the same, the difference being that... Figure 11 The apparatus shown may also include:

[0126] The third acquisition module 1106 is used to acquire the open-circuit voltage value of the battery at the initial moment;

[0127] The fourth acquisition module 1107 permanently acquires the SOC at the initial moment based on the open-circuit voltage value at the initial moment and the mapping relationship between the battery open-circuit voltage and SOC.

[0128] Furthermore, the third acquisition module 1106 is specifically used for:

[0129] If the battery current is less than a preset value, the measured real-time voltage is determined as the open-circuit voltage value of the battery at the initial moment; or

[0130] When the battery is in a stable state, the open-circuit voltage value of the battery at the initial moment is determined based on the current in the stable state and the measured real-time voltage.

[0131] According to the battery model-based method and apparatus for determining battery SOC provided in this application, a battery model corresponding to the battery is determined according to the specific requirements of the SOC determination process, and the relevant parameters and values ​​of the battery model are obtained. After determining the relationship between the battery SOC and relevant information (such as the parameters of the battery model and the measured real-time voltage), the battery SOC is determined based on the relevant information. Thus, since, except for the real-time voltage, the parameters of the battery model and other relevant information are fixed or known at the current moment during the battery SOC determination process, only the real-time voltage of the battery at the current moment needs to be obtained to determine the SOC value at the next moment based on the relationship between the battery SOC and relevant information. This application enables the observation of battery capacity based on a battery model; by simply measuring the real-time voltage of the battery, an accurate estimation of the battery SOC under varying loads can be achieved.

[0132] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0133] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this application.

[0134] In the several embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical or other forms.

[0135] See Figure 12 , Figure 12 An electronic device is provided, including a processor and a memory. The memory stores computer instructions, which, when executed by the processor, cause the processor to perform the computer instructions to achieve the following: Figure 1 , Figures 5 to 7 The method and its detailed scheme are shown.

[0136] It should be understood that the above-described device embodiments are merely illustrative, and the device disclosed in this invention can be implemented in other ways. For example, the division of units / modules described in the above embodiments is only a logical functional division, and there may be other division methods in actual implementation. For example, multiple units, modules, or components may be combined, integrated into another system, or some features may be ignored or not executed.

[0137] Furthermore, unless otherwise specified, the functional units / modules in the various embodiments of the present invention can be integrated into one unit / module, or each unit / module can exist physically separately, or two or more units / modules can be integrated together. The integrated units / modules described above can be implemented in hardware or as software program modules.

[0138] If the integrated unit / module is implemented in hardware, the hardware can be digital circuits, analog circuits, etc. The physical implementation of the hardware structure includes, but is not limited to, transistors, memristors, etc. Unless otherwise specified, the processor or chip can be any suitable hardware processor, such as a CPU, GPU, FPGA, DSP, and ASIC, etc. Unless otherwise specified, the on-chip cache, off-chip memory, and storage can be any suitable magnetic or magneto-optical storage medium, such as resistive random access memory (RRAM), dynamic random access memory (DRAM), static random access memory (SRAM), enhanced dynamic random access memory (EDRAM), high-bandwidth memory (HBM), hybrid memory cube (HMC), etc.

[0139] If the integrated unit / module is implemented as a software program module and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer electronic device (which may be a personal computer, server, or network electronic device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this disclosure. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0140] This application also provides a chip. In some embodiments, the chip includes a processor, the processor being configured to perform, for example... Figure 1 , Figures 5 to 7 The method and its refinement are shown. In other embodiments, the chip includes, as... Figures 8 to 11 The prediction device shown.

[0141] This application also provides a battery management system for performing tasks such as... Figure 1 , Figures 5 to 7 The method and its detailed scheme are shown.

[0142] This application embodiment also provides a non-transitory computer storage medium storing a computer program, which, when executed by multiple processors, causes the processors to perform actions such as... Figure 1 , Figures 5 to 7 The method and its detailed scheme are shown.

[0143] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this application. Furthermore, any changes or modifications made by those skilled in the art based on the ideas of this application, and on the specific implementation methods and application scope of this application, are all within the scope of protection of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for determining battery SOC based on a battery model, characterized in that, include: Obtain the battery model corresponding to the battery, the numerical values ​​of the parameters of the battery model, and the mapping relationship between the battery open-circuit voltage and SOC; The battery model is a simplified battery model, a first-order battery model, or a second-order battery model. Only the real-time voltage of the battery measured at the current moment is obtained; and Based on the values ​​of the parameters, the mapping relationship between the battery open-circuit voltage and SOC, the measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment, the SOC at the next moment is determined by discretizing the state equation of the battery model.

2. The determination method as described in claim 1, characterized in that, Also includes: Based on the values ​​of the parameters, the mapping relationship between the battery open-circuit voltage and SOC, the measurement time interval, the real-time voltage at the current moment, and the internal state value of the battery model at the current moment, the internal state value at the next moment is determined.

3. The determination method as described in claim 1, characterized in that, The step of determining the SOC at the next moment based on the values ​​of the parameters, the mapping relationship between the battery open-circuit voltage and SOC, the measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment includes: Based on the values ​​of the parameters, the mapping relationship between the battery open-circuit voltage and SOC, the measurement time interval, the real-time voltage at the current moment, the SOC at the current moment, and the internal state value of the battery model at the current moment, the battery SOC at the next moment is determined.

4. The determination method according to any one of claims 1 to 3, characterized in that, Also includes: The measurement time interval is determined based on the frequency of load changes in the battery.

5. The determination method according to any one of claims 1 to 3, characterized in that, Also includes: Obtain the open-circuit voltage value of the battery at the initial moment; The initial SOC is obtained based on the open-circuit voltage value at the initial moment and the mapping relationship between the battery open-circuit voltage and SOC.

6. The determination method according to any one of claims 1 to 3, characterized in that, The process of obtaining the open-circuit voltage value of the battery at the initial moment includes: If the battery current is less than a preset value, the measured real-time voltage is determined as the open-circuit voltage value of the battery at the initial moment; or When the battery is in a stable state, the open-circuit voltage value of the battery at the initial moment is determined based on the current in the stable state and the measured real-time voltage.

7. The determination method according to any one of claims 1 to 3, characterized in that, The parameters include one or more resistance parameters and / or one or more capacitance parameters.

8. A device for determining battery SOC based on a battery model, characterized in that, include: The first acquisition module is used to acquire the battery model corresponding to the battery, the value of the parameters of the battery model, and the mapping relationship between the battery open-circuit voltage and SOC. The battery model is a simplified battery model, a first-order battery model, or a second-order battery model. The second acquisition module is used to acquire only the real-time voltage of the battery measured at the current moment; as well as The first determining module is used to determine the SOC at the next moment by discretizing the state equation of the battery model based on the value of the parameter, the mapping relationship between the battery open-circuit voltage and SOC, the measurement time interval, the real-time voltage at the current moment, and the SOC at the current moment.

9. A chip, characterized in that, The chip includes a processor for performing the determination method as described in any one of claims 1 to 7; or... The chip includes the determining device as described in claim 8.

10. A battery management system, characterized in that, Used to perform the determination method as described in any one of claims 1 to 7.

11. An electronic device, characterized in that, It includes at least a memory and a processor, wherein the memory stores a computer program, and the processor, when executing the computer program in the memory, implements the steps of the method according to any one of claims 1 to 7.

12. A computer-readable storage medium, characterized in that, The computer-readable medium stores a computer program that, when executed by a processor, implements the method of any one of claims 1 to 7.

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