Battery lithium plating detection method and apparatus, and device, vehicle, medium and program product

Abstract

The present disclosure relates to a battery lithium plating detection method and apparatus, and a device, a vehicle, a medium and a program product. The method comprises: determining the actual direct-current internal resistance of a battery in each charge sub-stage during step charge, wherein the step charge comprises at least two charge sub-stages, and the battery is charged at a target charge rate and a constant current in each charge sub-stage; determining the target direct-current internal resistance of the battery in a corresponding charge sub-stage, wherein the target direct-current internal resistance is a predicted value of direct-current internal resistance that is obtained by means of a preset mathematical model; and if the difference value between the actual direct-current internal resistance and the target direct-current internal resistance is greater than a preset difference threshold value, determining that the battery is in a lithium plating state.

Description

Battery lithium deposition detection method, device, equipment, vehicle, medium and program product

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to Chinese patent application No. 202311023352.4 filed on August 14, 2023, filed by Beijing CHJ Automotive Technology Co., Ltd., and entitled “Battery lithium deposition detection method, device, equipment, medium and vehicle”, the full text of which is incorporated by reference into this disclosure. Technical Field

[0003] The present disclosure relates to the field of vehicle technology, and in particular to a battery lithium deposition detection method, device, equipment, vehicle, medium, and program product. Background Art

[0004] During the charging process of a lithium-ion battery, lithium ions are deintercalated from the positive electrode and intercalated into the negative electrode. However, under certain abnormal conditions, the deintercalated lithium ions cannot be intercalated into the negative electrode. Instead, the lithium ions are deposited on the negative electrode's surface, forming a layer of gray material. This phenomenon is called lithium plating. Lithium plating is a wear and tear condition in lithium-ion batteries. After lithium plating occurs, the battery's lifespan declines rapidly, and continued use in this condition can pose safety risks.

[0005] In order to solve the above technical problems, the relevant technology provides the following technical solutions: by superimposing a weak disturbance signal during the constant current charging process to measure the battery impedance corresponding to different charge capacities (State of Charge, SOC) at different frequencies, and extracting the change law of the real part of the impedance at a specific frequency, if the real part of the impedance or the imaginary part of the impedance shows a rapid decrease trend at the set charge capacity as the charging progresses, it indicates that lithium plating has occurred, and the charging current can be reduced until the charging is completed. However, since the change in charging current can also cause a sudden change in the battery's impedance, if the sudden decrease in impedance during the charging process is used as a criterion for lithium plating and applied to the step charge (STC) process, it is easy to cause a misjudgment of lithium plating.

[0006] Summary of the Invention

[0007] The present disclosure provides a battery lithium deposition detection method, device, equipment, vehicle, medium and program product.

[0008] The present disclosure first provides a battery lithium deposition detection method, comprising:

[0009] Determining an actual DC internal resistance of the battery in each charging sub-stage during a step-charging process, wherein the step-charging process includes at least two charging sub-stages, and the battery is charged at a target charging rate constant current in each charging sub-stage;

[0010] Determining a target DC internal resistance of the battery in a corresponding charging sub-stage; wherein the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model;

[0011] If the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold, it is determined that the battery is in a lithium deposition state.

[0012] The disclosed embodiment compares the difference between the actual DC internal resistance and the target DC internal resistance of the battery in each charging sub-stage during the step-by-step charging process with a preset difference threshold. When the difference between the two is greater than the preset difference threshold, it indicates that the actual DC internal resistance deviates significantly from the target DC internal resistance, thereby determining that the battery is in a lithium deposition state. The battery is not affected by current changes during the step-by-step charging process, thereby reducing false positives in lithium deposition and achieving fast and accurate online lithium deposition detection.

[0013] The present disclosure also provides a battery lithium deposition detection device, comprising:

[0014] a first determining module configured to determine an actual DC internal resistance of the battery in each charging sub-stage during a step-charging process; wherein the step-charging process includes at least two charging sub-stages, and the battery is charged at a target charging rate constant current in each charging sub-stage;

[0015] a second determining module configured to determine a target DC internal resistance of the battery in a corresponding charging sub-stage; wherein the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model;

[0016] The third determining module is configured to determine that the battery is in a lithium deposition state if a difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold.

[0017] The present disclosure also provides a battery lithium deposition detection device, comprising: a memory and a processor;

[0018] The memory stores executable programs or instructions;

[0019] The processor runs the program or instruction to implement the battery lithium deposition detection method as described above.

[0020] The present disclosure also provides a vehicle, comprising a controller and a battery; wherein the controller is configured to execute any of the above-described battery lithium deposition detection methods.

[0021] The present disclosure also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor of an electronic device, the battery lithium deposition detection method as described above can be implemented.

[0022] The present disclosure also provides a computer program; the computer program includes computer-readable code, and when the computer-readable code is executed in a processor of an electronic device, the processor in the electronic device can implement the battery lithium deposition detection method as described above.

[0023] The present disclosure also provides a computer program product, which includes a computer-readable code, or a non-volatile computer-readable storage medium carrying the computer-readable code. When the computer-readable code runs in a processor of an electronic device, the processor in the electronic device can implement the battery lithium deposition detection method as described above.

[0024] The technical solution provided by the present disclosure has the following advantages compared with the existing technology:

[0025] The battery lithium deposition detection method provided by the embodiment of the present disclosure determines the actual DC internal resistance of the battery in each charging sub-stage during a step-by-step charging process. The step-by-step charging process includes at least two charging sub-stages. The battery is charged at a target charging rate and constant current in each charging sub-stage. After determining the target DC internal resistance of the battery in the corresponding charging sub-stage, if the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference value, the battery is determined to be in a lithium deposition state, and the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model. Thus, by comparing the difference between the actual DC internal resistance and the target DC internal resistance of the battery in each charging sub-stage during the step-by-step charging process with a preset difference threshold, if the above difference value is greater than the preset difference threshold, it indicates that the actual DC internal resistance deviates significantly from the target DC internal resistance, and the battery is determined to be in a lithium deposition state. This can reduce the degree of interference of current changes during the step-by-step charging process on the process of determining that the battery is in a lithium deposition state, thereby reducing the probability of false positives, and achieving fast and accurate online lithium deposition detection.

[0026] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, rather than limiting the present disclosure. Other features and aspects of the present disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0028] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] FIG1 is a schematic flow chart of a method for detecting lithium deposition in a battery according to an embodiment of the present disclosure;

[0030] FIG2 is a schematic diagram of a curve showing a change in charging rate over time during a step-by-step charging process according to an embodiment of the present disclosure;

[0031] FIG3 is a schematic diagram of a curve showing a change in actual DC internal resistance of a battery over time provided by an embodiment of the present disclosure;

[0032] FIG4 is a schematic diagram of a process for determining the actual DC internal resistance of a battery in each charging sub-stage during a step-by-step charging process according to an embodiment of the present disclosure;

[0033] FIG5 is a schematic diagram of a curve showing a change in actual DC internal resistance over time after smoothing provided by an embodiment of the present disclosure;

[0034] FIG6 is a schematic diagram of a flow chart of determining a target DC internal resistance of a battery in a corresponding charging sub-stage according to an embodiment of the present disclosure;

[0035] FIG7 is a schematic flow chart of another method for detecting lithium deposition in a battery provided by an embodiment of the present disclosure;

[0036] FIG8 is a schematic diagram of a negative electrode potential change curve of a battery in different states provided by an embodiment of the present application;

[0037] FIG9 is a schematic structural diagram of a battery lithium deposition detection device provided in an embodiment of the present disclosure;

[0038] FIG10 is a schematic structural diagram of an electronic device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0039] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features therein can be combined with each other in the absence of conflict.

[0040] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0041] In order to solve the technical problems raised in the background technology section, the embodiments of the present disclosure provide a battery lithium deposition detection method, device, equipment, vehicle, medium and program product. The battery lithium deposition detection method includes: determining the actual DC internal resistance of the battery in each charging sub-stage during a step-by-step charging process; wherein the step-by-step charging process includes at least two charging sub-stages, and the battery is charged at a target charging rate constant current in each charging sub-stage; determining the target DC internal resistance of the battery in the corresponding charging sub-stage; wherein the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model; and the corresponding charging sub-stage includes the qth charging sub-stage, q is an integer greater than or equal to 1 and less than or equal to Q; Q is used to characterize the number of charging sub-stages included in the at least two charging sub-stages; if the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold, it is determined that the battery is in a lithium deposition state. Therefore, by comparing the difference between the actual DC internal resistance and the target DC internal resistance of the battery in each charging sub-stage during the step-by-step charging process with the preset difference threshold, when the difference between the two is greater than the preset difference threshold, it indicates that the actual DC internal resistance deviates greatly from the target DC internal resistance, and the battery is determined to be in a lithium deposition state. It is not affected by the current changes during the step-by-step charging process of the battery, reduces the misjudgment of lithium deposition, and realizes fast and accurate online lithium deposition detection.

[0042] The battery lithium deposition detection method, device, equipment, vehicle, medium and program product provided by the embodiments of the present disclosure will be exemplarily described below with reference to Figures 1 to 10.

[0043] FIG1 is a flow chart of a method for detecting lithium deposition in a battery according to an embodiment of the present disclosure. Referring to FIG1 , the method for detecting lithium deposition in a battery may include the following steps:

[0044] S110: Determine the actual DC internal resistance of the battery in each charging sub-stage during the step-by-step charging process.

[0045] The step-by-step charging process includes at least two charging sub-stages; the battery is charged at a target charging rate and constant current in each charging sub-stage.

[0046] In one embodiment, the charge rate is used to characterize the speed of battery charging, and is specifically used to indicate the current value required for the battery to be charged to its rated capacity within a specified time.

[0047] As the charging process continues, the battery's charge capacity gradually increases. The step-by-step charging process is divided into at least two charging sub-stages according to the charge capacity from low to high. The charging sub-stages and charge capacity intervals can correspond one-to-one, and each charging sub-stage corresponds to a target charging rate.

[0048] Figure 2 is a schematic diagram of a curve showing the change of charging rate over time during the step-by-step charging process provided by an embodiment of the present disclosure. In Figure 2, the horizontal axis is time, which can be measured in seconds (S), and the vertical axis is the charging rate, which can be measured in charging speed (C).

[0049] As shown in Figure 2, in the charging sub-stage corresponding to the lower charge capacity range, charging is performed at a higher charge rate. As the charge capacity increases, the charging rate is reduced in a step-by-step manner. In the charging sub-stage corresponding to the higher charge capacity range, charging is performed at a lower charge rate, thereby giving full play to the advantage of step-by-step charging: maximizing the battery's fast charging capability.

[0050] In one embodiment, the actual DC internal resistance can be obtained by measuring the battery using a measuring instrument or device; for example, when the measuring instrument or device includes an electrochemical workstation, the real part of the battery impedance can be obtained by measuring the battery using the electrochemical workstation.

[0051] In one embodiment, the actual DC internal resistance can also be obtained indirectly; for example, the voltage and current values ​​of the battery in the charging sub-stage can be used to obtain the ratio of the battery voltage change to the corresponding current change as the actual DC internal resistance.

[0052] Optionally, in each charging sub-phase, a square wave pulse excitation of a preset frequency is superimposed on the charging current.

[0053] The square wave pulse has a rectangular profile, and its rise and fall times are much shorter than the pulse duration. During each charging sub-stage, the battery is charged at a constant current. When a square wave pulse of a preset frequency is superimposed on the charging current, the corresponding charging current fluctuates, and so does the voltage. The battery's voltage and current values ​​during the square wave pulse excitation process are obtained, and the ratio of the change in voltage to the change in current over the preset duration is used as the actual DC internal resistance.

[0054] It is understood that the embodiments of the present disclosure only exemplify the use of square wave pulse excitation, and do not constitute a limitation on the battery lithium deposition detection method provided in the embodiments of the present disclosure. In other embodiments, other waveform excitations, such as sine pulse excitation and cosine pulse excitation, may also be used, which is not limited here.

[0055] S120: Determine a target DC internal resistance of the battery in a corresponding charging sub-stage.

[0056] The target DC internal resistance is a predicted value of the DC internal resistance obtained through a preset mathematical model.

[0057] In one embodiment, the corresponding charging sub-stage includes the qth charging sub-stage; q is an integer greater than or equal to 1 and less than or equal to Q; Q is an integer greater than or equal to 2 and is used to characterize the number of charging sub-stages included in the at least two charging sub-stages.

[0058] In one embodiment, the target DC internal resistance may be an ideal DC internal resistance when the battery is charged with a constant current.

[0059] In one embodiment, the preset mathematical model can be established based on the correlation between the target DC internal resistance and the charge capacity; illustratively, the charge capacity of the corresponding charging sub-stage is input into the preset mathematical model, and the charge capacity of the corresponding charging sub-stage is processed by the preset mathematical model to obtain the target DC internal resistance of the corresponding charging sub-stage.

[0060] S130: If the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold, determine that the battery is in a lithium deposition state.

[0061] Accordingly, if the difference between the actual DC internal resistance and the target DC internal resistance is less than or equal to the preset difference threshold, the operation of determining whether the battery is in the lithium deposition state may not be performed.

[0062] In practical applications, the battery state includes a lithium deposition state and a non-lithium deposition state.

[0063] Figure 3 is a schematic diagram of a curve showing the change in the actual DC internal resistance of a battery provided by an embodiment of the present disclosure over time. In Figure 3, the horizontal axis can be time in seconds (s), and the vertical axis can be the actual DC internal resistance in milliohms (mΩ).

[0064] In Figure 3, the solid line shows the curve of the actual DC internal resistance of the battery changing over time when the battery is in the lithium deposition state, and the dotted line shows the curve of the actual DC internal resistance of the battery changing over time when the battery is in the non-lithium deposition state. Referring to Figure 3, the actual DC internal resistance of the battery in the lithium deposition state is smaller than that in the non-lithium deposition state, thereby increasing the difference between the actual DC internal resistance of the battery in the lithium deposition state and the target DC resistance.

[0065] Therefore, the degree of deviation between the actual DC internal resistance and the target DC internal resistance can be represented by the difference between the actual DC internal resistance and the target DC internal resistance, so as to determine whether the battery is in a lithium deposition state; for example, if the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold, it can be determined that the battery is in a lithium deposition state, and if the difference between the actual DC internal resistance and the target DC resistance is not greater than the preset difference threshold, it can be determined that the battery is in a non-lithium deposition state.

[0066] In one embodiment, the difference between the actual DC internal resistance and the target DC internal resistance includes at least one of an absolute difference, a relative difference, and a ratio between the two; for example, when the absolute difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset absolute difference, that is, |actual DC internal resistance-target DC internal resistance|>preset absolute difference, it can be indicated that the actual DC internal resistance deviates greatly from the target DC internal resistance, and it is determined that the battery is in a lithium deposition state; for another example, when the relative difference between the actual DC internal resistance and the target DC internal resistance is greater than the preset relative difference, that is, |actual DC internal resistance-target DC internal resistance|÷target DC internal resistance×100%>preset relative difference, it can be indicated that the actual DC internal resistance deviates greatly from the target DC resistance, and it is determined that the battery is in a lithium deposition state; for another example, when the ratio of the actual DC internal resistance to the target DC resistance is less than the preset ratio, that is, actual DC internal resistance÷target DC resistance<preset ratio, it can be indicated that the actual DC resistance deviates greatly from the target DC resistance, and it can be determined that the battery is in a lithium deposition state.

[0067] It should be noted that the embodiment of the present disclosure divides the step-type charging process into at least two charging sub-stages. In each charging sub-stage, the difference between the actual DC internal resistance and the target DC internal resistance is compared with the preset difference value to determine whether the battery is in a lithium deposition state. The above-mentioned technical solution provided by the embodiment of the present disclosure is different from the related art in which the sudden reduction of battery impedance is used as the basis for judging lithium deposition. The detection result is not affected by the current change during the step-type charging process, thereby improving the stability and accuracy of the battery state.

[0068] As can be seen from the above, the battery lithium plating detection method provided by the embodiment of the present disclosure determines the actual DC internal resistance of the battery in each charging sub-stage during the step-by-step charging process, and the step-by-step charging process includes at least two charging sub-stages. The battery is charged at a target charging rate constant current in each charging sub-stage. After determining the target DC internal resistance of the battery in the corresponding charging sub-stage, if the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference value, it is determined that the battery is in a lithium plating state, and the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model. Thus, by comparing the difference between the actual DC internal resistance and the target DC resistance of the battery in each charging sub-stage during the step-by-step charging process with a preset difference threshold, if the above difference value is greater than the preset difference threshold, it indicates that the deviation between the actual DC internal resistance and the target DC internal resistance is large, and the battery is determined to be in a lithium plating state, thereby reducing the interference degree of the current change during the step-by-step charging process of the battery on the process of determining that the battery is in a lithium plating state, thereby reducing the probability of misjudgment of lithium plating, and achieving fast and accurate online lithium plating detection.

[0069] Based on the above embodiment, determining the actual DC internal resistance of the battery in each charging sub-stage during the step-by-step charging process can be achieved through the process shown in Figure 4. Figure 4 is a schematic diagram of the process of determining the actual DC internal resistance of the battery in each charging sub-stage during the step-by-step charging process according to an embodiment of the present disclosure. As shown in Figure 4, the process may include the following steps:

[0070] S411. Obtain the voltage and current values ​​of the battery during the charging process.

[0071] In one embodiment, during the battery charging process, the voltage value and the current value may be obtained in real time or at preset intervals.

[0072] S412: Obtain a voltage change and a current change corresponding to a first preset time period according to the voltage value and the current value.

[0073] In one embodiment, the voltage change is the difference between the voltage value at the end of the first preset time period and the voltage value at the start of the first preset time period, and the current change is the difference between the current value at the end of the first preset time period and the current value at the start of the first preset time period; exemplarily, the first preset time period can be set to N time steps or preset time intervals for obtaining voltage values / current values, and N can be an integer greater than or equal to 2.

[0074] S413. Determine the actual DC internal resistance.

[0075] The actual DC internal resistance is equal to the ratio of the change in voltage value to the change in current value.

[0076] From the above, it can be seen that the battery lithium deposition detection method provided by the embodiment of the present disclosure calculates the actual DC internal resistance by the ratio of the voltage value change to the current value change, which not only simplifies the analysis process of the actual DC internal resistance, but also can reflect the actual change of the battery internal resistance, thereby improving the accuracy of the actual DC internal resistance.

[0077] Based on the above embodiments, the battery lithium deposition detection method provided in the embodiments of the present disclosure may further perform the following operations:

[0078] An average value of the current actual DC internal resistance and a previously preset number of actual DC internal resistances is calculated, and the average value is determined as the current actual DC internal resistance.

[0079] It should be noted that the curve shown in Figure 3 is drawn based on the original data; the actual DC internal resistance obtained by calculation is prone to jitter noise due to sampling errors and the influence of the test environment. To filter out the jitter noise, the curve of the actual DC internal resistance changing over time can be smoothed.

[0080] In one embodiment, the smoothing of the curve of the actual DC internal resistance changing over time can be achieved by:

[0081] The current actual DC internal resistance and a preset number (M-1) of actual DC internal resistances before it are selected, and the average value of the selected M actual DC internal resistances is calculated. The average value is the current actual DC internal resistance after smoothing. The average value can be calculated using formula (1):

[0082] in is the current actual DC internal resistance after smoothing, and k is the sequence number of the current DC internal resistance.

[0083] Figure 5 is a schematic diagram of a curve showing the change of the actual DC internal resistance over time after smoothing provided by an embodiment of the present disclosure. The physical meanings of the ordinate and abscissa in Figure 5 are the same as those in Figure 3.

[0084] In FIG5 , the preset number is set to 39, that is, M is equal to 40, and the current actual DC internal resistance (whose sequence number is k, where k is an integer greater than or equal to 40) and the 39 actual DC internal resistances before it (corresponding sequence numbers are: k-39, k-38, k-37, ..., k-1) are selected. The average value of the selected 40 actual DC internal resistances (corresponding sequence numbers are k-39 to k) is calculated. The average value of each 40 actual DC internal resistances is selected and calculated in sequence, that is, the average value of the 1st to 40th actual DC internal resistances is calculated, and the average value of the 2nd to 41st actual DC internal resistances is calculated. This is repeated in this way to obtain a smoothed curve of the actual DC internal resistance changing with time.

[0085] It should be noted that, in the initial stage of battery lithium plating detection, when the number of actual DC internal resistances determined is less than or equal to the preset number (i.e., k is less than or equal to 39), the actual DC internal resistance corresponding to this period is equal to 0; when the number of actual DC internal resistances to be determined is greater than the preset number (i.e., k is greater than or equal to 40), the first smoothed actual DC internal resistance can be obtained.

[0086] As can be seen from the above, in the battery lithium deposition detection method provided by the embodiment of the present disclosure, the average value is determined by the above method, which can filter out the jitter noise generated by sampling error and the influence of the test environment.

[0087] Based on the above embodiments, in the battery lithium deposition detection method provided by the embodiment of the present disclosure, determining the target DC internal resistance of the battery in the corresponding charging sub-stage can be achieved through the process shown in Figure 6. Figure 6 is a schematic diagram of the process of determining the target DC internal resistance of the battery in the corresponding charging sub-stage provided by the embodiment of the present disclosure. As shown in Figure 6, the process may include the following steps:

[0088] S621: Obtain the current charge capacity of the battery and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs.

[0089] S622: Substitute the current charge capacity, the charge capacity at the initial moment of the charging sub-stage to which the current moment belongs, and the actual DC internal resistance into a preset mathematical model to obtain a target DC internal resistance corresponding to the current moment;

[0090] Among them, the target DC internal resistance in the preset mathematical model is exponentially related to the charge capacity.

[0091] In one embodiment, as the charge capacity increases, the target DC internal resistance tends to decrease.

[0092] In one embodiment, the preset mathematical model can be expressed by formula (2);

[0093] Among them, Z is the target DC internal resistance, Z0 is the actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs, SOC0 is the charge capacity at the initial moment of the charging sub-stage to which the current moment belongs, SOC is the charge capacity at the current moment, and A and m are characteristic parameters in the preset mathematical model.

[0094] As can be seen from the above, the battery lithium deposition detection method provided by the embodiments of the present disclosure obtains the battery's current charge capacity, the charge capacity at the initial moment of the charging sub-stage to which the current moment belongs, and the actual DC internal resistance. These data are then substituted into a preset mathematical model to obtain the target DC internal resistance for the current charging sub-stage. In the preset mathematical model, the target DC internal resistance and charge capacity are exponentially related. Thus, through this operation, the accuracy of the target DC internal resistance for the current charging sub-stage can be improved.

[0095] Based on the above embodiments, in the battery lithium deposition detection method provided by the embodiment of the present disclosure, the preset mathematical model includes characteristic parameters; the above method may further perform the following operations:

[0096] The charge capacity and actual DC internal resistance at the current moment, as well as the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs, are substituted into a preset mathematical model to obtain the actual values ​​of the characteristic parameters corresponding to the current moment; based on the actual values ​​of the characteristic parameters corresponding to the current moment, the characteristic parameters in the preset mathematical model are corrected.

[0097] The modified preset mathematical model is used to calculate the target DC internal resistance at the next moment.

[0098] In this embodiment, the current charge capacity and actual DC internal resistance, as well as the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs, are substituted into a preset mathematical model, and an extended Kalman filter (EQF) algorithm is used to identify the actual values ​​of characteristic parameters (e.g., A and m) corresponding to the current moment. Based on the actual values ​​of the characteristic parameters, the characteristic parameters in the preset mathematical model used to calculate the target DC internal resistance at the current moment are then corrected, such that the corrected characteristic parameters are equal to the actual values ​​of the characteristic parameters corresponding to the current moment. The target DC internal resistance at the next moment is predicted using the corrected preset mathematical model. Alternatively, the previous charge capacity and actual DC internal resistance, as well as the previous charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the previous moment belongs, are substituted into the preset mathematical model, and the actual values ​​of the characteristic parameters A and m corresponding to the current moment are identified using the EQF algorithm. The characteristic parameters in the preset mathematical model are then corrected, such that the corrected characteristic parameters are equal to the actual values ​​of the characteristic parameters corresponding to the previous moment, and the target DC internal resistance at the current moment is calculated using the corrected preset mathematical model.

[0099] By performing the above-mentioned real-time identification and correction of the characteristic parameters A and m in the preset mathematical model, the accuracy of the target DC internal resistance is improved.

[0100] Based on the above embodiments, the battery lithium deposition detection method provided in the embodiments of the present disclosure may further perform the following operations:

[0101] Determine the current charging substage and the corresponding target charging rate based on the battery's current charge capacity and a preset charging table; and determine that the battery charging rate is equal to the target charging rate corresponding to the current charging substage.

[0102] Among them, in the preset charging table, the step-by-step charging process is divided into at least two charging sub-stages according to the charge capacity from low to high. Each charging sub-stage corresponds to a target charging rate, and the target charging rates corresponding to different charging sub-stages are different; the target charging rate decreases step by step with the increase of charge capacity.

[0103] In one embodiment, a preset charging table is stored in a battery management system (BMS); when the battery charge capacity is equal to 100%, the BMS cuts off the charging path between the external power supply and the battery to reduce the risk of battery overcharging; when the battery charge capacity is lower than the set minimum charge capacity, the BMS cuts off the discharge path between the battery and the external power device to reduce the risk of battery overdischarge, thereby extending the battery life.

[0104] Exemplarily, in the preset charging table, the step-by-step charging process can be divided into five charging sub-stages according to the charge capacity from low to high. The first charge capacity interval is [0, 20%), and the corresponding target charging rate is K1; the second charge capacity interval is [20%, 40%), and the corresponding target charging rate is K2; the third charge capacity interval is [40%, 60%), and the corresponding target charging rate is K3; the fourth charge capacity interval is [60%, 80%), and the corresponding target charging rate is K4; the fifth charge capacity interval is [80%, 100%), and the corresponding target charging rate is K5; among which, the size relationship of the target charging rates corresponding to the five charging sub-stages is: K1>K2>K3>K4>K5>0.

[0105] It is understood that the embodiment of the present disclosure only exemplifies the step-by-step charging process, including five charging sub-stages and the corresponding relationship between the five charging sub-stages and the charge capacity intervals, but does not constitute a limitation on the battery lithium deposition detection method provided by the embodiment of the present disclosure. In other embodiments, the step-by-step charging sub-stages can be divided according to the requirements of the battery lithium deposition detection method, and the number of charging sub-stages can be two, three, four, six, or more, which is not limited here.

[0106] Based on the above embodiments, the battery lithium deposition detection method provided in the embodiments of the present disclosure can also be implemented by determining the target DC internal resistance of the battery in the corresponding charging sub-stage in the following manner:

[0107] If the fluctuation rate of the battery's charging rate within the second preset time period is less than or equal to the fluctuation threshold, a target DC internal resistance of the battery in the corresponding charging sub-stage is determined.

[0108] When the charging sub-stage is switched, the charging rate of the battery is adjusted to the target charging rate corresponding to the charging sub-stage after the switch.

[0109] Accordingly, if the fluctuation rate of the battery's charging rate within the second preset time period is not greater than the fluctuation threshold, the operation of determining the target DC internal resistance of the battery in the corresponding charging sub-stage may not be performed.

[0110] In one embodiment, the fluctuation rate of the battery's charge rate within the second preset time period is less than or equal to the fluctuation threshold, which can indicate that the battery's charge rate remains stable within the second preset time period.

[0111] For example, as the charging process progresses, the battery's charge capacity gradually increases. When the charge capacity exceeds the current charge capacity interval and enters the next charge capacity interval, the corresponding charging sub-stage is switched, and the battery's charge rate is also switched to the target charge rate corresponding to the charging sub-stage after the switch. Since a decrease in the charge rate will cause a decrease in the charging current, that is, an increase in the current variation, the calculated actual DC internal resistance decreases. Therefore, if the charge rate after the switch is less than the charge rate before the switch, the difference between the corresponding actual DC internal resistance and the target internal resistance is likely to exceed the preset difference threshold, but lithium plating does not necessarily occur in the battery at this time. This may lead to a misjudgment of lithium plating; therefore, in order to reduce the misjudgment of lithium plating caused by the above situation, if the fluctuation rate of the battery's charging rate within the second preset time period is less than or equal to the fluctuation threshold, that is, the battery's charging rate has not switched, the step of determining the target DC internal resistance of the battery in the corresponding charging sub-stage and its subsequent steps are determined; and if the battery's charging rate changes within the second preset time period, that is, the battery enters the next charging sub-stage, the battery's charging rate is switched (the corresponding charging current is also switched), then the step of determining the target DC internal resistance of the battery in the corresponding charging sub-stage and its subsequent steps may not be executed, and lithium plating detection may not be performed.

[0112] For example, as shown in Figure 3 or Figure 5, compared with the state without lithium deposition, the actual DC internal resistance corresponding to moments a, b, c and d when the battery is in the lithium deposition state is abnormally reduced; wherein, the reduction in DC internal resistance corresponding to moments a, c and d is the abnormal reduction in actual DC internal resistance caused by lithium deposition of the battery, while moment b is the abnormal reduction in actual DC internal resistance caused by switching of the charging rate (or charging current).

[0113] It should be noted that the battery charging rate can be determined in advance, and then the target DC internal resistance of the battery in the corresponding charging sub-stage can be determined by the above method; and the battery charging rate can be determined by the method provided in the above embodiment.

[0114] From the above, it can be seen that this embodiment can reduce the probability of abnormal reduction of actual DC internal resistance caused by switching of charging rate (or charging current), thereby reducing the probability of misjudgment of lithium plating.

[0115] FIG7 is a flow chart of another method for detecting lithium deposition in a battery according to an embodiment of the present disclosure. Referring to FIG7 , the above process may include the following steps:

[0116] S710: Obtain current and voltage values ​​of the battery during a step-by-step charging process, wherein the current and voltage values ​​change periodically over time.

[0117] In each charging sub-stage of the step-type charging, the battery is charged with a constant current; by superimposing a pulse wave of a preset frequency on the charging current for excitation, the frequency of the current value and voltage value pulse wave changes periodically, and the pulse wave may include a square wave pulse, which is not limited here.

[0118] S720: Calculate the actual DC internal resistance based on the current value and the voltage value.

[0119] Exemplarily, based on the current value and voltage value and the corresponding preset time length, the voltage change and current change corresponding to the preset time length are calculated, and the ratio of the voltage change to the current change is used as the actual DC internal resistance.

[0120] S730: Determine whether current switching occurs

[0121] Exemplarily, the current charging current (or charging rate) of the battery is compared with the charging current (or charging rate) of the previous acquisition cycle. If the deviation between the current charging current (or charging rate) and the charging current (or charging rate) of the previous acquisition cycle exceeds the preset deviation threshold, it is determined that current switching has occurred, and the judgment result is yes. At this time, S740 can be executed; if the deviation between the current charging current (or charging rate) and the charging current (or charging rate) of the previous acquisition cycle does not exceed the preset deviation threshold, it is determined that current switching has not occurred, and the judgment result is no. At this time, S750 can be executed.

[0122] S740: Do not perform lithium plating detection.

[0123] S750: Calculate the target DC internal resistance of the battery using a preset mathematical model.

[0124] Exemplarily, the charge capacity and actual DC internal resistance at the previous moment, as well as the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the previous moment belongs, are substituted into a preset mathematical model to determine the characteristic parameters corresponding to the previous moment; then the charge capacity at the current moment, as well as the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs, are substituted into the preset mathematical model, the characteristic parameters in the preset mathematical model being the characteristic parameters corresponding to the previous moment determined in the previous step, and the target DC internal resistance corresponding to the current moment is calculated.

[0125] S760: When the deviation between the actual DC internal resistance and the target DC internal resistance is greater than a preset threshold, determine that the battery is in a lithium deposition state.

[0126] Exemplarily, when the deviation between the actual DC internal resistance and the target DC internal resistance is greater than a preset threshold, it is determined that the battery is in a lithium deposition state; when the deviation between the actual DC internal resistance and the target DC internal resistance is less than or equal to the preset threshold, it is determined that the battery is not in a lithium deposition state.

[0127] The disclosed embodiment also verifies the test results of the above-mentioned battery lithium deposition detection method. Figure 8 is a schematic diagram of the negative electrode potential change curve of batteries in different states provided by the embodiment of the present application. The horizontal axis of Figure 8 is time, in seconds (s), and the vertical axis is the negative electrode point (N). As shown in Figure 8, the negative electrode potential of the battery in the non-lithium deposition state is above 0V, while the negative electrode potential of the battery in the lithium deposition state drops to below 0V at time a, time c, and time d, indicating that lithium deposition has occurred in the battery, verifying the accuracy of the lithium deposition detection result.

[0128] Based on the same inventive concept, the present disclosure also provides a battery lithium deposition detection device. FIG9 is a schematic structural diagram of the battery lithium deposition detection device provided by the present disclosure. As shown in FIG9, the battery lithium deposition detection device 900 includes:

[0129] A first determining module 901 is configured to determine an actual DC internal resistance of the battery in each charging sub-stage during a step-charging process, wherein the step-charging process includes at least two charging sub-stages, and the battery is charged at a target charging rate and constant current in each charging sub-stage;

[0130] A second determining module 902 is configured to determine a target DC internal resistance of the battery in a corresponding charging sub-stage; wherein the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model;

[0131] The third determining module 903 is configured to determine that the battery is in a lithium deposition state if the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold.

[0132] In one embodiment, the first determination module 901 is configured to obtain the voltage value and current value of the battery during the charging process; obtain the voltage change and current change corresponding to the first preset time length based on the voltage value and current value; determine the actual DC internal resistance; wherein the actual DC internal resistance is equal to the ratio of the voltage value change to the current value change.

[0133] In one embodiment, the first determining module 901 is configured to calculate an average value of the current actual DC internal resistance and a preset number of actual DC internal resistances, and determine the average value as the current actual DC internal resistance.

[0134] In one embodiment, the second determination module 902 is configured to obtain the charge capacity of the battery at the previous moment and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs; substitute the charge capacity at the current moment and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs into a preset mathematical model to obtain the target DC internal resistance corresponding to the charging sub-stage at the current moment; wherein the target DC internal resistance in the preset mathematical model is exponentially related to the charge capacity.

[0135] In one embodiment, the preset mathematical model includes characteristic parameters, and the second determination module 902 is configured to substitute the charge capacity and actual DC internal resistance at the previous moment and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the previous moment belongs into the preset mathematical model to obtain the actual values ​​of the characteristic parameters corresponding to the current moment; based on the actual values ​​of the characteristic parameters corresponding to the current moment, the characteristic parameters of the preset mathematical model are corrected; wherein the corrected preset mathematical model is used to calculate the target DC internal resistance at the next moment.

[0136] In one embodiment, the battery lithium plating detection device also includes: a fourth determination module, configured to determine the charging sub-stage and the corresponding target charging rate at the current moment according to the current charge capacity of the battery and a preset charging table, and determine that the charging rate of the battery is equal to the target charging rate corresponding to the charging sub-stage at the current moment; wherein, in the preset charging table, the step-by-step charging process is divided into at least two charging sub-stages according to the charge capacity from low to high, each charging sub-stage corresponds to a target charging rate, and different charging sub-stages correspond to different target charging rates, and the target charging rate decreases step by step with the increase of the charge capacity.

[0137] In one embodiment, the fourth determination module is configured to determine the target DC internal resistance of the battery in the corresponding charging sub-stage if the fluctuation rate of the battery's charging rate within a second preset time period is less than or equal to a fluctuation threshold; wherein, when the charging sub-stage is switched, the battery's charging rate is adjusted to the target charging rate corresponding to the charging sub-stage after the switch.

[0138] In some embodiments, the battery lithium deposition detection device further includes: an excitation module configured to superimpose a square wave pulse excitation of a preset frequency on the charging current in each charging sub-stage.

[0139] The device can be implemented using software and / or hardware and can be integrated into any processor or electronic device with computing capabilities. For any content not described in detail in the device embodiments of the present disclosure, reference can be made to the description in any method embodiment of the present disclosure.

[0140] Based on the above embodiments, FIG10 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present disclosure. Referring to FIG10 , the electronic device 1000 includes: a memory 1001 and a processor 1002; the memory 1001 stores executable programs or instructions; the processor 1002 runs the programs or instructions to implement any of the above-mentioned battery lithium deposition detection methods, which has corresponding beneficial effects. To avoid repeated description, it will not be repeated here.

[0141] The processor 1002 may be a central processing unit (CPU) or other forms of processing units with data processing capabilities and / or instruction execution capabilities, and may control other components in the computer to perform desired functions.

[0142] The memory 1001 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory. Non-volatile memory may include, for example, read-only memory (ROM), a hard disk, a flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 1002 may execute the program instructions to implement the method steps of the various embodiments of the present disclosure described above and / or other desired functions.

[0143] Based on the above implementation, the present disclosure further provides a vehicle, which includes the above electronic device.

[0144] Exemplarily, the vehicle may further include other on-board equipment or devices, such as a vehicle control unit and a storage unit, etc., which are not limited here.

[0145] On the basis of the above-mentioned embodiments, an embodiment of the present disclosure further provides a computer-readable storage medium on which a computer program or instruction is stored. When the computer program or instruction is executed by a processor, the processor executes the method steps of various embodiments of the present disclosure to implement any of the above-mentioned battery lithium deposition detection methods.

[0146] The computer-readable medium may be included in the electronic device, or may exist independently without being incorporated into the electronic device.

[0147] Computer readable storage media can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can include, but is not limited to, a system, device or component of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, RAM, ROM, an erasable programmable read-only memory (EPROM), a 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 thereof.

[0148] In addition to the above-mentioned methods and apparatuses, embodiments of the present disclosure may also be a computer program product, which includes computer program instructions. When the computer program instructions are executed by a processor, the processor is caused to perform the method steps of various embodiments of the present disclosure.

[0149] The computer program product may be written in any combination of one or more programming languages ​​to implement the operations of embodiments of the present invention, including object-oriented programming languages ​​such as Java, C++, and conventional procedural programming languages ​​such as C or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's computing device, as a stand-alone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0150] Based on the foregoing embodiments, an embodiment of the present application further provides a computer program product, which includes a computer-readable code, or a non-volatile computer-readable storage medium carrying the computer-readable code; when the computer-readable code runs in a processor of an electronic device, the processor of the electronic device can implement a battery lithium deposition detection method as provided in any of the previous embodiments.

[0151] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0152] The foregoing description is intended only to provide specific embodiments of the present disclosure, intended to enable those skilled in the art to understand and implement the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is not intended to be limited to the embodiments described herein, but rather to be construed in the broadest manner consistent with the principles and novel features disclosed herein. Industrial Applicability

[0153] The present disclosure relates to a battery lithium deposition detection method, apparatus, equipment, vehicle, medium, and program product. The method includes: determining the actual DC internal resistance of the battery in each charging sub-stage during a step-by-step charging process; the step-by-step charging process includes at least two charging sub-stages, and the battery is charged at a target charging rate and constant current in each charging sub-stage; determining the target DC internal resistance of the battery in the corresponding charging sub-stage; the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model; if the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold, determining that the battery is in a lithium deposition state. The present disclosure determines that the battery is in a lithium deposition state when the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold, thereby achieving fast and accurate online lithium deposition detection.

Claims

1. A battery lithium deposition detection method, the method comprising: Determine the actual DC internal resistance of the battery in each charging sub-stage during the step-type charging process; wherein the step-type charging process includes at least two charging sub-stages, and the battery is charged at a target charging rate constant current in each charging sub-stage; Determining a target DC internal resistance of the battery in a corresponding charging sub-stage; wherein the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model; If the difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold, it is determined that the battery is in a lithium deposition state.

2. The battery lithium deposition detection method according to claim 1, wherein determining the actual DC internal resistance of the battery in each charging sub-stage during the step-by-step charging process comprises: Obtaining the voltage and current values ​​of the battery during charging; According to the voltage value and the current value, obtaining a voltage change amount and a current change amount corresponding to a first preset time length; Determine the actual DC internal resistance; wherein the actual DC internal resistance is equal to the ratio of the voltage value change to the current value change.

3. The battery lithium deposition detection method according to claim 2, further comprising: Calculate the average value of the current actual DC internal resistance and the actual DC internal resistance of the previous preset number; The average value is determined as the current actual DC internal resistance.

4. According to any one of claims 1 to 3, the step of determining the target DC internal resistance of the battery in the corresponding charging sub-stage comprises: Obtaining the charge capacity of the battery at the current moment and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs; The charge capacity at the current moment and the charge capacity and the actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs are substituted into the preset mathematical model to obtain the target DC internal resistance of the charging sub-stage corresponding to the current moment; wherein the target DC internal resistance in the preset mathematical model is exponentially related to the charge capacity.

5. The battery lithium deposition detection method according to claim 4, wherein the preset mathematical model includes characteristic parameters, and the method further comprises: Substituting the charge capacity and actual DC internal resistance at the current moment and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs into the preset mathematical model to obtain the actual value of the characteristic parameter corresponding to the current moment; Based on the actual value of the characteristic parameter corresponding to the current moment, the characteristic parameter in the preset mathematical model is corrected; wherein the corrected preset mathematical model is used to calculate the target DC internal resistance at the next moment.

6. The battery lithium deposition detection method according to claim 4, further comprising: According to the charge capacity of the battery at the current moment and the preset charging table, the charging sub-stage to which the current moment belongs and the corresponding target charging rate are determined; wherein, in the preset charging table, the step-by-step charging is performed from low to high according to the charge capacity. The charging process is divided into at least two charging sub-stages; each charging sub-stage corresponds to a target charging rate, different charging sub-stages correspond to different target charging rates, and the target charging rate decreases step by step with the increase of charge capacity; Determine that the charging rate of the battery is equal to the target charging rate corresponding to the charging sub-stage at the current moment.

7. The battery lithium deposition detection method according to claims 4-6, wherein determining the target DC internal resistance of the battery in the corresponding charging sub-stage comprises: If the fluctuation rate of the charging rate of the battery within a second preset time period is less than or equal to a fluctuation threshold, the target DC internal resistance of the battery in the corresponding charging sub-stage is determined; wherein, when the charging sub-stage is switched, the charging rate of the battery is adjusted to the target charging rate corresponding to the charging sub-stage after the switch.

8. The battery lithium deposition detection method according to claim 1, further comprising: In each of the charging sub-phases, a square wave pulse excitation of a preset frequency is superimposed on the charging current.

9. A battery lithium deposition detection device, comprising: A first determination module is configured to determine an actual DC internal resistance of the battery in each charging sub-stage during a step-by-step charging process; wherein the step-by-step charging process includes at least two charging sub-stages, and the battery is charged at a target charging rate constant current in each charging sub-stage; A second determination module is configured to determine a target DC internal resistance of the battery in a corresponding charging sub-stage; wherein the target DC internal resistance is a predicted value of the DC internal resistance obtained by a preset mathematical model; The third determination module is configured to determine that the battery is in a lithium deposition state if a difference between the actual DC internal resistance and the target DC internal resistance is greater than a preset difference threshold.

10. The battery lithium deposition detection device according to claim 9, The first determination module is configured to obtain the voltage value and current value of the battery during the charging process; obtain the voltage change and current change corresponding to the first preset time according to the voltage value and the current value; and determine the actual DC internal resistance; wherein, The actual DC internal resistance is equal to the ratio of the voltage value change to the current value change.

11. The battery lithium deposition detection device according to claim 10, wherein the first determination module is configured to calculate an average value of a current actual DC internal resistance and a previously preset number of actual DC internal resistances, and determine the average value as the current actual DC internal resistance.

12. According to any one of claims 9 to 11, the battery lithium deposition detection device, the second determination module is configured to obtain the charge capacity of the battery at the current moment and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs; substitute the charge capacity at the current moment and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs into the preset mathematical model to obtain the target DC internal resistance of the charging sub-stage corresponding to the current moment; wherein, The target DC internal resistance in the preset mathematical model is exponentially related to the charge capacity.

13. The battery lithium deposition detection device according to claim 12, wherein the preset mathematical model includes characteristic parameters, and the second determination module is further configured to substitute the charge capacity and actual DC internal resistance at the current moment and the charge capacity and actual DC internal resistance at the initial moment of the charging sub-stage to which the current moment belongs into the preset mathematical model to obtain the actual value of the characteristic parameter corresponding to the current moment; based on the actual value of the characteristic parameter corresponding to the current moment, the characteristic parameters of the preset mathematical model are corrected; wherein, The modified preset mathematical model is used to calculate the target DC internal resistance at the next moment.

14. The battery lithium deposition detection device according to claim 12, further comprising: A fourth determination module is configured to determine the charging substage and the corresponding target charging rate at the current moment according to the current charge capacity of the battery and a preset charging table; Determine that the charging rate of the battery is equal to the target charging rate corresponding to the charging substage to which the current moment belongs; wherein, in the preset charging table, the step-by-step charging process is divided into at least two charging substages according to the charge capacity from low to high; each charging substage corresponds to a target charging rate, and different charging substages correspond to different target charging rates; the target charging rate in the preset charging table decreases step by step with the increase of the charge capacity in the preset charging table.

15. The battery lithium deposition detection device according to claim 14, wherein the fourth determination module is further configured to determine the target DC internal resistance of the battery in the corresponding charging sub-stage if the fluctuation rate of the battery's charging rate within the second preset time period is less than or equal to a fluctuation threshold; wherein, When the charging sub-stage is switched, the charging rate of the battery is adjusted to a target charging rate corresponding to the charging sub-stage after the switching.

16. The battery lithium deposition detection device according to claim 9, further comprising: The excitation module is configured to superimpose a square wave pulse excitation of a preset frequency on the charging current in each charging sub-stage.

17. A battery lithium deposition detection device, comprising: Memory and processor; The memory stores executable programs or instructions; The processor runs the program or instruction to implement the battery lithium deposition detection method as described in any one of claims 1-8.

18. A vehicle comprising a controller and a battery; wherein: The controller is used to execute the battery lithium deposition detection method as described in any one of claims 1 to 8.

19. A computer-readable storage medium having a computer program or instruction stored thereon, wherein when the computer program is executed by a processor of an electronic device, the battery lithium deposition detection method as described in any one of claims 1 to 8 can be implemented.

20. A computer program; the computer program comprises a computer readable code, and when the computer readable code is executed in a processor of an electronic device, the processor in the electronic device can implement the battery lithium deposition detection method as claimed in any one of claims 1 to 8.

21. A computer program product, comprising a computer-readable code, or a non-volatile computer-readable storage medium carrying the computer-readable code, wherein when the computer-readable code runs in a processor of an electronic device, the processor in the electronic device can implement the battery lithium deposition detection method as described in any one of claims 1 to 8.

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