Voltage prediction method, device, system and storage medium considering historical current

Abstract

The present invention provides a voltage prediction method, device, system, and storage medium that consider historical current, belonging to the technical field of battery pack voltage prediction. The method includes: obtaining the battery cell voltage and the total current of the battery pack at the end of the historical current; determining the corrected terminal voltage of the battery cell based on the battery cell voltage, the total current of the battery pack, and the first-order circuit equivalent model of the battery pack; correcting the first-order circuit equivalent model based on the corrected terminal voltage to obtain a first-order circuit equivalent correction model; determining the corrected voltage value of the battery cell based on the first-order circuit equivalent correction model, and determining the voltage prediction value of the battery pack based on the corrected voltage value of the battery cell. When the present invention performs voltage prediction using the first-order circuit equivalent correction model, the influence of historical current is taken into account, and the influence of historical current on voltage prediction is taken into account, thereby improving the accuracy of the determined voltage prediction value.

Description

Technical Field

[0001] The present invention relates to the technical field of battery pack voltage prediction, and in particular to a voltage prediction method, device, system and storage medium that consider historical current. Background Art

[0002] Generally speaking, in the field of low-voltage battery systems, vehicle manufacturers need to implement the power prediction function. The specific power prediction strategy in the low-voltage field is: after using a specific current operating condition as the current input, the voltage value of the battery pack is predicted.

[0003] Experimental verification found that when the historical current represents a discharge condition, the greater the historical current, the lower the battery pack voltage. When the historical current represents a charge condition, the greater the historical current, the higher the battery pack voltage. This means that historical current has a certain impact on voltage prediction. However, existing technologies do not consider the impact of historical current when predicting voltage, resulting in low voltage prediction accuracy.

[0004] Therefore, there is an urgent need to provide a voltage prediction method, device, system and storage medium that take historical current into account, so as to eliminate the adverse effects of false trajectories on traffic flow results and improve the accuracy of traffic flow statistics results in cross-sectional areas. Summary of the Invention

[0005] In view of this, it is necessary to provide a voltage prediction method, device, system and storage medium that take historical current into account to solve the technical problem in the prior art that the influence of historical current on predicted voltage is not taken into account, resulting in low accuracy of predicted voltage value.

[0006] On the one hand, in order to solve the above technical problems, the present invention provides a voltage prediction method considering historical current, comprising:

[0007] Obtain the cell voltage and total current of the battery pack at the end of the historical current;

[0008] Determining a corrected terminal voltage of the battery cell based on the battery cell voltage, the total current of the battery pack and a first-order circuit equivalent model of the battery pack;

[0009] Correcting the first-order circuit equivalent model based on the correction terminal voltage to obtain a first-order circuit equivalent correction model;

[0010] A cell correction voltage value is determined based on the first-order circuit equivalent correction model, and a voltage prediction value of the battery pack is determined based on the cell correction voltage value.

[0011] In a possible implementation, the correction terminal voltage is:

[0012] Vxz =OCV-Voltage input -Current input ×R 0

[0013] Where, V xz is the corrected terminal voltage at the end of the historical current; OCV is the open circuit voltage at the end of the historical current; Voltage input is the cell voltage at the end of the historical current; Current input The total current of the battery pack at the end of the historical current; R 0 is the internal resistance in ohms.

[0014] In a possible implementation, the first-order circuit equivalent correction model is:

[0015]

[0016]

[0017] Where, Correct the voltage value for the battery cell; is the open circuit voltage at time t, is the total current of the battery pack at time t; is the polarization voltage at time t; is the polarization internal resistance; is a polarized capacitor.

[0018] In a possible implementation, before determining the cell correction voltage value based on the first-order circuit equivalent correction model, the method further includes:

[0019] Determining an influence coefficient of the correction terminal voltage based on multiple measurement results of the historical current;

[0020] Optimizing the first-order circuit equivalent correction model based on the influence coefficient to obtain a first-order circuit equivalent optimization model;

[0021] Then, determining the cell correction voltage value based on the first-order circuit equivalent correction model includes:

[0022] The cell correction voltage value is determined based on the first-order circuit equivalent optimization model.

[0023] In a possible implementation, the first-order circuit equivalent optimization model is:

[0024]

[0025]

[0026] Where, Correct the voltage value for the battery cell; is the open circuit voltage at time t, is the total current of the battery pack at time t; is the optimized polarization voltage at time t; R 0 is the internal resistance in ohms; is the polarization internal resistance; is the polarized capacitance; V xz is the corrected terminal voltage at the end of the historical current; is the influence coefficient of the correction terminal voltage.

[0027] In a possible implementation, determining the cell correction voltage value based on the first-order circuit equivalent correction model includes:

[0028] determining physical parameters associated with the first-order circuit equivalent modified model;

[0029] Determining target physical parameters at a target state of charge and a target temperature based on a mapping relationship between the physical parameters, the state of charge, and the temperature;

[0030] The cell correction voltage value is determined based on the target physical parameter and the first-order circuit equivalent correction model.

[0031] In one possible implementation, determining the predicted voltage value of the battery pack based on the corrected cell voltage value includes:

[0032] Obtaining the number of battery cells in the battery pack, and determining a first battery pack voltage value based on the number of battery cells and the battery cell corrected voltage value;

[0033] obtaining a total battery pack current and an additional resistance of the battery pack, and determining a second battery pack voltage value based on the total battery pack current and the additional resistance;

[0034] The sum of the first battery pack voltage value and the second battery pack voltage value is used as the voltage prediction value.

[0035] On the other hand, the present invention also provides a voltage prediction device taking into account historical current, comprising:

[0036] A historical current related parameter acquisition unit is used to obtain the cell voltage and total current of the battery pack at the end of the historical current;

[0037] a cell terminal voltage correction unit, configured to determine a corrected terminal voltage of the cell based on the cell voltage, the total current of the battery pack, and a first-order circuit equivalent model of the battery pack;

[0038] an equivalent model correction unit, configured to correct the first-order circuit equivalent model based on the correction terminal voltage to obtain a first-order circuit equivalent correction model;

[0039] A voltage prediction unit is used to determine a cell correction voltage value based on the first-order circuit equivalent correction model, and to determine a voltage prediction value of the battery pack based on the cell correction voltage value.

[0040] On the other hand, the present invention also provides a battery management system, including a memory and a processor, wherein:

[0041] The memory is used to store programs;

[0042] The processor is coupled to the memory and is configured to execute the program stored in the memory to implement the steps of the voltage prediction method considering historical current described in any one of the possible implementations above.

[0043] On the other hand, the present invention also provides a computer-readable storage medium for storing computer-readable programs or instructions, which, when executed by a processor, can implement the steps in the voltage prediction method considering historical current described in any of the above possible implementation methods.

[0044] The beneficial effects of the present invention are as follows: the voltage prediction method considering historical current provided by the present invention obtains the cell voltage and the total current of the battery pack at the end of the historical current, and determines the corrected terminal voltage of the cell under the influence of the historical current based on the cell voltage and the total current of the battery pack, and then corrects the first-order circuit equivalent model based on the corrected terminal voltage. This can take the influence of the historical current into account when subsequently predicting the voltage through the first-order circuit equivalent correction model, and takes into account the influence of the historical current on the voltage prediction, thereby improving the accuracy of the determined voltage prediction value. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0046] Figure 1 A schematic flow chart of an embodiment of a voltage prediction method considering historical current provided by the present invention;

[0047] Figure 2 A schematic diagram of an embodiment of a first-order equivalent circuit provided by the present invention;

[0048] Figure 3A schematic diagram of a flow chart of an embodiment of determining the influence coefficient of the correction terminal voltage provided by the present invention;

[0049] Figure 4 A schematic diagram of an embodiment of the process of determining the corrected voltage value of the battery cell in step S104 provided by the present invention;

[0050] Figure 5 A schematic diagram of another embodiment of the first-order equivalent circuit provided by the present invention;

[0051] Figure 6 A schematic diagram of an embodiment of a flow chart for determining a voltage prediction value in step S104 provided by the present invention;

[0052] Figure 7 A schematic structural diagram of an embodiment of a voltage prediction device taking into account historical current provided by the present invention;

[0053] Figure 8 This is a schematic structural diagram of an embodiment of the battery management system provided by the present invention. DETAILED DESCRIPTION

[0054] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0055] It should be understood that the schematic drawings are not drawn to scale. The flowcharts used in the present invention illustrate operations implemented according to some embodiments of the present invention. It should be understood that the operations of the flowcharts can be implemented out of sequence, and steps that have no logical contextual relationship can be reversed in order or implemented simultaneously. In addition, those skilled in the art, guided by the content of the present invention, can add one or more other operations to the flowcharts or remove one or more operations from the flowcharts. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different networks and / or processor systems and / or microcontroller systems.

[0056] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0057] The present invention provides a voltage prediction method, device, system and storage medium considering historical current, which are described below respectively.

[0058] Figure 1 A flow chart of an embodiment of a voltage prediction method considering historical current provided by the present invention is shown as follows: Figure 1 As shown in Figure 2, the voltage prediction methods considering historical current include:

[0059] S101. Obtain the cell voltage and total current of the battery pack at the end of the historical current.

[0060] Specifically, a charge / discharge test is performed on the battery pack based on the historical current, and the cell voltage and the total current of the battery pack are obtained at the end of the test, that is, at the end of the historical current.

[0061] The relationship between a battery cell and a battery pack is that a battery pack includes multiple battery cells.

[0062] S102 . Determine a corrected terminal voltage of the battery cell based on the battery cell voltage, the total current of the battery pack, and a first-order circuit equivalent model of the battery pack.

[0063] In a specific embodiment of the present invention, the first-order circuit equivalent model is constructed based on the first-order equivalent circuit. Figure 2 As shown, it includes an ideal voltage source (open circuit voltage: OCV), an ohmic internal resistance R0, a polarization internal resistance R1 and a polarization capacitor C1, wherein the polarization internal resistance R1 and the polarization capacitor C1 are connected in parallel.

[0064] Among them, the ideal voltage source is related to the state of charge (SOC) of the battery.

[0065] S103 , correcting the first-order circuit equivalent model based on the correction terminal voltage to obtain a first-order circuit equivalent correction model.

[0066] Since the correction terminal voltage is determined by the historical current, the first-order circuit equivalent correction model obtained after correction includes the influence of the historical current on it.

[0067] S104 : Determine a cell correction voltage value based on a first-order circuit equivalent correction model, and determine a battery pack voltage prediction value based on the cell correction voltage value.

[0068] It should be understood that the voltage prediction method considering current history in the embodiments of the present invention can be implemented in any device based on the voltage prediction method considering current history, such as a battery management system (BMS). Specifically, the voltage prediction method considering current history is stored in the aforementioned device as a pre-programmed program. When the device is powered on, the program is invoked and the voltage prediction method considering current history is implemented.

[0069] Compared with the prior art, the voltage prediction method taking historical current into consideration provided by the embodiment of the present invention obtains the cell voltage and total current of the battery pack at the end of the historical current, and determines the corrected terminal voltage of the cell under the influence of the historical current based on the cell voltage and the total current of the battery pack, and then corrects the first-order circuit equivalent model based on the corrected terminal voltage. This can take the influence of the historical current into account when subsequently predicting the voltage through the first-order circuit equivalent correction model, and take into account the influence of the historical current on the voltage prediction, thereby improving the accuracy of the determined voltage prediction value.

[0070] In a specific embodiment of the present invention, the correction terminal voltage is:

[0071] V xz =OCV-Voltage input -Current input ×R 0

[0072] Where, V xz is the corrected terminal voltage at the end of the historical current; OCV is the open circuit voltage at the end of the historical current; Voltage input is the cell voltage at the end of the historical current; Current input It is the total current of the battery pack at the end of the historical current.

[0073] In a specific embodiment of the present invention, the first-order circuit equivalent correction model is:

[0074]

[0075]

[0076] Where, Correct the voltage value for the battery cell; is the open circuit voltage at time t, is the total current of the battery pack at time t; is the polarization voltage at time t.

[0077] It can be seen from the above formula that the embodiment of the present invention takes the historical current into consideration before determining the corrected voltage value of the battery cell each time, thereby ensuring the accuracy of the corrected voltage value of the battery cell.

[0078] After analyzing a large number of historical current test results, it is found that the historical current has limited influence on the voltage prediction value. In order to avoid excessive consideration of the influence of the historical current on the voltage prediction value, a reasonable historical current influence factor is introduced. In some embodiments of the present invention, Figure 3 As shown, before step S104, the voltage prediction method considering historical current further includes:

[0079] S301, determining an influence coefficient of the correction terminal voltage based on multiple measurement results of historical current;

[0080] S302, optimizing the first-order circuit equivalent correction model based on the influence coefficient to obtain a first-order circuit equivalent optimization model;

[0081] The step S104 of determining the cell correction voltage value based on the first-order circuit equivalent correction model includes:

[0082] The cell correction voltage value is determined based on the first-order circuit equivalent optimization model.

[0083] The embodiment of the present invention determines the influence coefficient of the correction terminal voltage based on multiple measurement results of historical current, thereby achieving quantitative evaluation of the influence, thereby making the constructed first-order circuit equivalent optimization model more consistent with the actual situation, and further improving the accuracy of the voltage prediction value.

[0084] In a specific embodiment of the present invention, the first-order circuit equivalent optimization model is:

[0085]

[0086]

[0087] Where, Correct the voltage value for the battery cell; is the open circuit voltage at time t, is the total current of the battery pack at time t; is the optimized polarization voltage at time t; R 0 is the internal resistance in ohms; is the polarization internal resistance; is the polarized capacitance; V xz is the corrected terminal voltage at the end of the historical current; is the influence coefficient of the correction terminal voltage.

[0088] The process of determining the influence coefficient k is as follows: putting the test results into the first-order circuit equivalent correction model, and using the data fitting method to calculate the most appropriate influence coefficient.

[0089] In a specific embodiment of the present invention, the influence coefficient k=0.2.

[0090] From the formula of the first-order circuit equivalent correction model above, it can be seen that in the process of solving the first-order circuit equivalent correction model, the ohmic internal resistance must be determined first. R 0. Polarization internal resistance , polarized capacitor Parameters such as , the accurate determination of these parameters can ensure the accuracy of the cell correction voltage value. Therefore, in some embodiments of the present invention, such as Figure 4 As shown, the step S104 of determining the cell correction voltage value based on the first-order circuit equivalent correction model includes:

[0091] S401. Determine physical parameters related to a first-order circuit equivalent correction model.

[0092] The physical parameters can be determined based on the physical meanings corresponding to the symbols in the first-order circuit equivalent correction model.

[0093] S402 : Determine target physical parameters at a target state of charge and a target temperature based on a mapping relationship between physical parameters, state of charge, and temperature.

[0094] The mapping relationship can be stored in different forms such as tables and graphs.

[0095] S403 : Determine a cell correction voltage value based on the target physical parameters and the first-order circuit equivalent correction model.

[0096] The embodiment of the present invention determines the target physical parameter based on parameters of multiple dimensions: state of charge, temperature, etc., thereby improving the accuracy of the determined target physical parameter and further improving the accuracy of the corrected voltage value of the battery cell.

[0097] Specifically, the process of establishing the mapping relationship can be as follows: in the life storage of the battery pack, a cycle test is performed under different temperature conditions with a specific current working condition, the test results are obtained, and the test results are analyzed using the least squares method to obtain R 0. R 1 and C 1.

[0098] Among them, the specific current condition is a current condition proposed from the perspective of functional safety. It is generally derived from the current pulse of side-by-side parking obtained by the vehicle manufacturer through actual testing, and is generally a discharge current condition.

[0099] In a specific embodiment of the present invention, the mapping relationship is stored in the form of a graph, that is:R 0. The relationship between temperature and current, R 1. The relationship between temperature and current and C 1. The relationship between temperature and current is stored in the form of a three-dimensional graph. The current SOC, temperature and current can be checked through the three-dimensional graph. R 0 value, R 1 value and C 1 value.

[0100] Since in practical applications, Figure 5 As shown, the battery pack includes an additional resistor R3 in addition to the battery cell. The additional resistor R3 is connected in series with the parallel structure of the polarization internal resistance and the polarization capacitor. Therefore, in some embodiments of the present invention, as shown in FIG. Figure 6 As shown, the step S104 of determining the voltage prediction value of the battery pack based on the corrected voltage value of the battery cell includes:

[0101] S601: Acquire the number of battery cells in a battery pack, and determine a first battery pack voltage value based on the number of battery cells and a corrected battery cell voltage value.

[0102] Specifically, the first battery pack voltage value is the product of the battery cell correction voltage value and the number of battery cells.

[0103] S602 : Obtain a total battery pack current and an additional resistance of the battery pack, and determine a second battery pack voltage value based on the total battery pack current and the additional resistance.

[0104] Specifically, the second battery pack voltage value is the product of the total battery pack current and the additional resistance.

[0105] S603 : Taking the sum of the first battery pack voltage value and the second battery pack voltage value as a voltage prediction value.

[0106] Specifically, the voltage prediction value is:

[0107]

[0108] Where, is the voltage prediction value; N is the number of battery cells.

[0109] To sum up, the voltage prediction method considering historical current proposed in the embodiment of the present invention, the first-order circuit equivalent model of the battery cell takes into account the influence of historical current and quantifies this influence through the influence coefficient, that is: accurately considers the influence of historical current and improves the accuracy of the final determined voltage prediction value.

[0110] In order to better implement the voltage prediction method considering historical current in the embodiment of the present invention, based on the voltage prediction method considering historical current, the embodiment of the present invention also provides a voltage prediction device considering historical current, such as Figure 7 As shown, the voltage prediction device 700 considering historical current includes:

[0111] The historical current related parameter acquisition unit 701 is used to obtain the cell voltage and total current of the battery pack at the end of the historical current;

[0112] The cell terminal voltage correction unit 702 is used to determine the corrected terminal voltage of the cell based on the cell voltage, the total current of the battery pack and the first-order circuit equivalent model of the battery pack;

[0113] An equivalent model correction unit 703 is configured to correct the first-order circuit equivalent model based on the correction terminal voltage to obtain a first-order circuit equivalent correction model;

[0114] The voltage prediction unit 704 is configured to determine a cell correction voltage value based on a first-order circuit equivalent correction model, and determine a voltage prediction value of the battery pack based on the cell correction voltage value.

[0115] The voltage prediction device 700 considering historical current provided in the above embodiment can implement the technical solution described in the above embodiment of the voltage prediction method considering historical current. The specific implementation principles of the above modules or units can refer to the corresponding contents in the above embodiment of the voltage prediction method considering historical current, which will not be repeated here.

[0116] like Figure 8 As shown, the present invention also provides a battery management system 800. The battery management system 800 includes a processor 801, a memory 802 and a display 803. Figure 8 Only some of the components of the battery management system 800 are shown, but it should be understood that implementation of all of the shown components is not required, and more or fewer components may be implemented instead.

[0117] In some embodiments, the processor 801 may be a central processing unit (CPU), a microprocessor, or other data processing chip, configured to execute program codes or process data stored in the memory 802 , such as the voltage prediction method considering historical current in the present invention.

[0118] In some embodiments, the memory 802 may be an internal storage unit of the battery management system 800, such as a hard disk or memory of the battery management system 800. In other embodiments, the memory 802 may also be an external storage device of the battery management system 800, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the battery management system 800.

[0119] Furthermore, the memory 802 may include both an internal storage unit of the battery management system 800 and an external storage device. The memory 802 is used to store application software installed in the battery management system 800 and various data.

[0120] In some embodiments, display 803 can be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen. Display 803 is used to display information about battery management system 800 and to present a visual user interface. Components 801-803 of battery management system 800 communicate with each other via a system bus.

[0121] In some embodiments of the present invention, when the processor 801 executes the voltage prediction program considering historical current in the memory 802, the following steps may be implemented:

[0122] Obtain the cell voltage and total current of the battery pack at the end of the historical current;

[0123] Determine the corrected terminal voltage of the battery cell based on the battery cell voltage, the total current of the battery pack and the first-order circuit equivalent model of the battery pack;

[0124] Correcting the first-order circuit equivalent model based on the correction terminal voltage to obtain the first-order circuit equivalent correction model;

[0125] The cell correction voltage value is determined based on the first-order circuit equivalent correction model, and the voltage prediction value of the battery pack is determined based on the cell correction voltage value.

[0126] It should be understood that, when the processor 801 executes the voltage prediction program considering historical current in the memory 802 , in addition to the above functions, it can also implement other functions. For details, please refer to the description of the corresponding method embodiment above.

[0127] The battery management system 800 in the embodiment of the present invention can be installed in passenger cars and commercial vehicles.

[0128] Accordingly, an embodiment of the present invention also provides a computer-readable storage medium, which is used to store computer-readable programs or instructions. When the program or instructions are executed by a processor, it can implement the steps or functions of the voltage prediction method considering historical current provided in the above-mentioned method embodiments.

[0129] Those skilled in the art will appreciate that all or part of the process flow of the above-described method embodiment can be implemented by instructing related hardware (such as a processor, controller, etc.) through a computer program, and the computer program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a magnetic disk, an optical disk, a read-only memory, or a random access memory.

[0130] The above is a detailed introduction to the voltage prediction method, device, system and storage medium that take into account historical current provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for technical personnel in this field, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A voltage prediction method considering historical current, characterized in that: include: Obtain the cell voltage and total current of the battery pack at the end of the historical current; Determining a corrected terminal voltage of the battery cell based on the battery cell voltage, the total current of the battery pack and a first-order circuit equivalent model of the battery pack; Correcting the first-order circuit equivalent model based on the correction terminal voltage to obtain a first-order circuit equivalent correction model; Determining a cell corrected voltage value based on the first-order circuit equivalent correction model, and determining a voltage prediction value of the battery pack based on the cell corrected voltage value; The correction terminal voltage is: V xz =OCV-Voltage input -Current input ×R 0 Where, V xz is the corrected terminal voltage at the end of the historical current; OCV is the open circuit voltage at the end of the historical current; Voltage input is the cell voltage at the end of the historical current; Current input The total current of the battery pack at the end of the historical current; R 0 is the internal resistance in ohms; The first-order circuit equivalent correction model is: Where, Correct the voltage value for the battery cell; is the open circuit voltage at time t, is the total current of the battery pack at time t; is the polarization voltage at time t; is the polarization internal resistance; is a polarized capacitor.

2. The voltage prediction method considering historical current according to claim 1, characterized in that: Before determining the cell correction voltage value based on the first-order circuit equivalent correction model, the method further includes: Determining an influence coefficient of the correction terminal voltage based on multiple measurement results of the historical current; Optimizing the first-order circuit equivalent correction model based on the influence coefficient to obtain a first-order circuit equivalent optimization model; Then, determining the cell correction voltage value based on the first-order circuit equivalent correction model includes: The cell correction voltage value is determined based on the first-order circuit equivalent optimization model.

3. The voltage prediction method considering historical current according to claim 2, characterized in that: The first-order circuit equivalent optimization model is: Where, Correct the voltage value for the battery cell; is the open circuit voltage at time t, is the total current of the battery pack at time t; is the optimized polarization voltage at time t; R 0 is the internal resistance in ohms; is the polarization internal resistance; is the polarized capacitance; V xz is the corrected terminal voltage at the end of the historical current; is the influence coefficient of the correction terminal voltage.

4. The voltage prediction method considering historical current according to claim 1, characterized in that: The determining of the cell correction voltage value based on the first-order circuit equivalent correction model includes: determining physical parameters associated with the first-order circuit equivalent modified model; Determining target physical parameters at a target state of charge and a target temperature based on a mapping relationship between the physical parameters, the state of charge, and the temperature; The cell correction voltage value is determined based on the target physical parameter and the first-order circuit equivalent correction model.

5. The voltage prediction method considering historical current according to claim 1, characterized in that: Determining a predicted voltage value of the battery pack based on the corrected voltage value of the battery cell includes: Obtaining the number of battery cells in the battery pack, and determining a first battery pack voltage value based on the number of battery cells and the battery cell corrected voltage value; obtaining a total battery pack current and an additional resistance of the battery pack, and determining a second battery pack voltage value based on the total battery pack current and the additional resistance; The sum of the first battery pack voltage value and the second battery pack voltage value is used as the voltage prediction value.

6. A voltage prediction device considering historical current, characterized in that: include: A historical current related parameter acquisition unit is used to obtain the cell voltage and total current of the battery pack at the end of the historical current; a cell terminal voltage correction unit, configured to determine a corrected terminal voltage of the cell based on the cell voltage, the total current of the battery pack, and a first-order circuit equivalent model of the battery pack; an equivalent model correction unit, configured to correct the first-order circuit equivalent model based on the correction terminal voltage to obtain a first-order circuit equivalent correction model; a voltage prediction unit, configured to determine a cell-corrected voltage value based on the first-order circuit equivalent correction model, and determine a voltage prediction value of the battery pack based on the cell-corrected voltage value; The correction terminal voltage is: V xz =OCV-Voltage input -Current input ×R 0 Where, V xz is the corrected terminal voltage at the end of the historical current; OCV is the open circuit voltage at the end of the historical current; Voltage input is the cell voltage at the end of the historical current; Current input The total current of the battery pack at the end of the historical current; R 0 is the internal resistance in ohms; The first-order circuit equivalent correction model is: Where, Correct the voltage value for the battery cell; is the open circuit voltage at time t, is the total current of the battery pack at time t; is the polarization voltage at time t; is the polarization internal resistance; is a polarized capacitor.

7. A battery management system, characterized in that: comprising a memory and a processor, wherein, The memory is used to store programs; The processor is coupled to the memory and is configured to execute the program stored in the memory to implement the steps of the voltage prediction method considering historical current as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that Used to store computer-readable programs or instructions, which, when executed by a processor, can implement the steps of the voltage prediction method considering historical current as described in any one of claims 1 to 5.

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