A detection method, system, device and storage medium for virtual connection of a battery sampling line

Abstract

The present invention provides a method, system, device and storage medium for detecting a loose connection of a battery sampling line. The method includes: obtaining the current and the first voltage difference of each sampled battery cell in a battery pack within a preset time; determining the sampled battery cells with a current less than a preset current threshold and a first voltage difference greater than or equal to a first preset voltage threshold as marked battery cells, and obtaining the positions of the marked battery cells; based on the positions of the marked battery cells, determining whether there are two adjacent marked battery cells; if there are two adjacent marked battery cells, determining whether the second voltage difference between the two adjacent marked battery cells is less than or equal to a second preset voltage threshold; if the second voltage difference is less than or equal to the second preset voltage threshold, determining the sampling line between the two adjacent marked battery cells as a loose connection point. Through the method, system, device and storage medium for detecting a loose connection of a battery sampling line provided by the present invention, the loose connection condition of the battery pack can be effectively detected.

Description

Technical Field

[0001] The present invention relates to the field of battery detection, and particularly to a method, system, device and storage medium for detecting virtual connection of a battery sampling line. Background Art

[0002] With the popularization of new energy vehicles such as pure electric vehicles, hybrid vehicles and hydrogen fuel vehicles, more and more people choose new energy vehicles, and the market share of new energy vehicles is also increasing. However, fires and other battery-related problems of new energy vehicles occur from time to time. Especially when there is a virtual connection in the sampling wire harness of the vehicle battery, it causes an increase in contact internal resistance, resulting in problems such as vehicle flameout, difficult starting and malfunction of the central control, with extremely high risks. Therefore, how to identify in advance whether the sampling wire harness of the battery voltage is virtually connected has become a key issue.

[0003] In the prior art, a BMS (Battery Management System) is used to detect the battery voltage. However, the BMS can only detect the open circuit and short power supply conditions of the sampling circuit, and cannot detect whether the sampling wire harness is virtually connected. Moreover, when a virtual connection occurs, the voltage fluctuation will cause the BMS to make incorrect logical judgments, resulting in continuous overcharging of the sampling wire core, leading to more serious traffic accidents. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art that the virtual connection of the sampling wire cannot be detected, so as to provide a method, system, device and storage medium for detecting the virtual connection of a battery sampling line.

[0005] According to a first aspect, the present invention provides a method for detecting virtual connection of a battery sampling line, the method comprising:

[0006] Obtaining the current and the first voltage difference of each sampling battery cell in the battery pack within a preset time;

[0007] Determining the sampling battery cells with the current less than a preset current threshold and the first voltage difference greater than or equal to a first preset voltage threshold as marked battery cells, and obtaining the positions of the marked battery cells;

[0008] Based on the positions of the marked battery cells, determining whether there are two adjacent marked battery cells;

[0009] If there are two adjacent marked battery cells, determining whether the second voltage difference between the two adjacent marked battery cells is less than or equal to a second preset voltage threshold;

[0010] If the second voltage difference is less than or equal to the second preset voltage threshold, determining that the sampling line between the two adjacent marked battery cells is a virtual connection point.

[0011] In this method, when there is a loose connection in the battery pack sampling line, the contact resistance at the corresponding contact position will inevitably increase. The increase in contact resistance will cause the sampling voltage to decrease. Therefore, by obtaining the first voltage difference of the sampled battery cells in the battery pack, the loose connection can be judged based on the voltage change. The sampled battery cells that meet the conditions of both current and the first voltage difference are marked, and the positions of the marked battery cells are determined. By gradually judging the positions of the marked battery cells, the specific position of the loose connection point can be judged, so as to realize the early detection of the loose connection situation of the battery pack, avoid the vehicle being continuously overcharged due to the voltage change caused by the loose connection of the sampling line in the BMS, and effectively detect the loose connection situation of the battery pack.

[0012] In one embodiment, the method further includes:

[0013] If there are no two adjacent marked battery cells, it is judged whether the current marked battery cell is the first battery cell or the last battery cell of the battery pack;

[0014] If the current marked battery cell is the first battery cell or the last battery cell of the battery pack, it is judged whether the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located are in parallel;

[0015] If the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located are not in parallel, it is judged whether a copper bar is connected to the adjacent position of the current marked battery cell;

[0016] If no copper bar is connected to the adjacent position of the current marked battery cell, it is determined that the negative sampling line of the first battery cell of the battery pack is broken, and the positive sampling line of the last battery cell of the battery pack is determined as the loose connection point.

[0017] In this method, when there are no two adjacent marked battery cells, the position of the current marked battery cell in the battery pack can be judged, the connection relationship between the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located can be judged, and whether a copper bar is connected to the adjacent position of the current marked battery cell can be judged, so as to determine the specific position of the loose connection point, increase the multiple possibilities of judging the existence of the loose connection point, and gradually judge the position of the loose connection point to improve the accuracy of the loose connection point position.

[0018] In one embodiment, the method further includes:

[0019] If a copper bar is connected to the adjacent position of the current marked battery cell, it is judged whether the current marked battery cell is the battery cell where the negative sampling line of the copper bar is located;

[0020] If the current marked battery cell is the battery cell where the negative sampling line of the copper bar is located, it is judged whether the current marked battery cell is the first sampled battery cell of the battery sampling chip;

[0021] If the currently marked battery cell is the first sampled battery cell of the battery sampling chip, then determine that the negative sampling line of the copper bar and the negative sampling line of the currently marked battery cell are virtual connection points.

[0022] In this method, when there is no copper bar connected to the adjacent position of the currently marked battery cell, it is possible to determine the specific position of the currently marked battery cell, so as to determine whether the currently marked battery cell is the first sampled battery cell of the battery sampling chip, so as to determine the specific position of the virtual connection point, increase the various possibilities of determining the existence of the virtual connection point, and gradually determine the position of the virtual connection point, improving the accuracy of the virtual connection point position.

[0023] In one embodiment, the method further includes:

[0024] If the currently marked battery cell is not the first sampled battery cell of the battery sampling chip, then determine that the negative sampling line of the copper bar is the virtual connection point.

[0025] In this method, when the currently marked battery cell is not the first sampled battery cell, the specific position of the virtual connection point can be determined.

[0026] In one embodiment, the method further includes:

[0027] If the currently marked battery cell is the battery cell where the positive sampling line of the copper bar is located, then determine whether the currently marked battery cell is the last sampled battery cell of the battery sampling chip;

[0028] If the currently marked battery cell is the last sampled battery cell of the battery sampling chip, then determine that the positive sampling line of the copper bar and the positive sampling line of the currently marked battery cell are virtual connection points.

[0029] In this method, when there is a copper bar connected to the adjacent position of the currently marked battery cell, it is possible to determine the specific position of the currently marked battery cell. When the currently marked battery cell is the battery cell where the positive sampling line of the copper bar is located and is the last sampled battery cell of the battery sampling chip, the position of the virtual connection point can be determined, increasing the various possibilities of determining the existence of the virtual connection point, and gradually determining the position of the virtual connection point, improving the accuracy of the specific position of the virtual connection point.

[0030] In one embodiment, the method further includes:

[0031] If the currently marked battery cell is not the last sampled battery cell of the battery sampling chip, then determine that the positive sampling line of the copper bar is the virtual connection point.

[0032] In this method, when the currently marked battery cell is not the last sampled battery cell, the specific position of the virtual connection point can be determined, increasing the various possibilities of determining the existence of the virtual connection point, and gradually determining the position of the virtual connection point, improving the accuracy of the virtual connection position.

[0033] In one embodiment, the method further includes:

[0034] Obtain the third voltage difference between the marked battery cell and the normal battery cell;

[0035] If the third voltage difference is less than the third preset voltage threshold, determine whether the voltage of the marked battery cell is always less than the preset value within the set duration during charging or discharging of the battery pack;

[0036] If the voltage of the marked battery cell is always less than the preset value within the set duration during charging or discharging of the battery pack, give an early warning for the virtual contact point.

[0037] In this method, by comparing the voltage differences between the marked battery cell and the normal battery cell, it is judged whether the voltage of the marked battery cell meets the conditions during charging or discharging of the battery pack, and when the conditions are met, an early warning is given for the virtual contact point to give an early warning for safety accidents and prevent the occurrence of safety accidents.

[0038] According to a second aspect, the present invention provides a detection system for virtual connection of battery sampling lines, the system comprising:

[0039] A first acquisition module, configured to acquire the current and the first voltage difference of each sampling battery cell in the battery pack within a preset time;

[0040] A second acquisition module, configured to determine the sampling battery cell with the current less than the preset current threshold and the first voltage difference greater than or equal to the first preset voltage threshold as the marked battery cell, and acquire the position of the marked battery cell;

[0041] A first judgment module, configured to judge whether there are two adjacent marked battery cells based on the position of the marked battery cell;

[0042] A second judgment module, configured to, if there are two adjacent marked battery cells, judge whether the second voltage difference between the two adjacent marked battery cells is less than or equal to the second preset voltage threshold;

[0043] A determination module, configured to, if the second voltage difference is less than or equal to the second preset voltage threshold, determine the sampling line between the two adjacent marked battery cells as the virtual contact point.

[0044] According to a third aspect, the present invention provides a computer device, comprising a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to execute the method for detecting virtual connection of battery sampling lines according to any one of the first aspect and its optional embodiments.

[0045] According to a fourth aspect, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the method for detecting a loose connection of a battery sampling line according to any one of the first aspect and its optional embodiments. Description of the Drawings

[0046] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0047] Figure 1 is a flowchart of a method for detecting a loose connection of a battery sampling line according to an embodiment of the present invention;

[0048] Figure 2 is a schematic diagram of a loose connection of the V1 negative electrode sampling line according to an embodiment of the present invention;

[0049] Figure 3 is a schematic diagram of a loose connection of the sampling line between the V1 negative electrode and the Vn positive electrode according to an embodiment of the present invention;

[0050] Figure 4 is a schematic diagram of a loose connection of any one of the two sampling lines before and after connecting the copper bus according to an embodiment of the present invention;

[0051] Figure 5 is a schematic diagram of a loose connection at the negative electrode sampling point of the battery cell and an adjacent copper bus according to an embodiment of the present invention;

[0052] Figure 6 is a schematic diagram of a loose connection at the last sampling point and an adjacent previous position being a copper bus according to an embodiment of the present invention;

[0053] Figure 7 is a schematic diagram of the single-cell voltage sampling point and the positive and negative electrodes according to an embodiment of the present invention;

[0054] Figure 8 is a block diagram of the structure of a detection system for a loose connection of a battery sampling line according to an embodiment of the present invention;

[0055] Figure 9 is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. Detailed Embodiments

[0056] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work belong to the scope of protection of the present invention.

[0057] With the popularization of new energy vehicles, the market share of new energy vehicles is getting higher and higher. However, with the occurrence of battery-related problems such as the fire of new energy vehicles, improving the safety performance of automotive batteries has become a top priority. At present, the BMS system can only locate the open circuit of the sampling line of the cell voltage and the short power supply lamp failure, and cannot locate the virtual connection of the single-cell voltage sampling line. However, the virtual connection of the sampling line will cause an increase in the BMS contact resistance. Since the resistance value is not fixed, the collected single-cell voltage is abnormal, resulting in incorrect diagnosis by the BMS, resulting in limited vehicle power or abnormal interruption of vehicle power. Even due to the incorrect activation of other functions, the state of charge of the battery is incorrect, resulting in overcharging of the vehicle cell, and ultimately leading to dangerous times such as battery thermal runaway.

[0058] In order to detect the virtual connection of the battery sampling line, an embodiment of the present invention provides a method for detecting the virtual connection of the battery sampling line, as Figure 1 shown, the method includes the following steps S1 to S5.

[0059] Step S1: Obtain the current and the first voltage difference of each sampling cell in the battery pack within a preset time.

[0060] In the embodiment of the present invention: Obtain the current I 1 at time t 2 and I t1 at time t t2 for each sampling cell in the battery pack; and obtain the first voltage difference ΔV1 of each sampling cell at time t 1 and time t 2 . Specifically, V1 t1 -V1 t2 =ΔV1, V2 t1 -V2 t2 =ΔV2... Vn t1 -Vn t2 =ΔVn. When the sampling line is virtually connected, the cell voltage will change correspondingly. Therefore, obtaining the first voltage difference is convenient for judging the possibility of virtual connection of the sampling line.

[0061] Step S2: Determine the sampling cells with current less than the preset current threshold and the first voltage difference greater than or equal to the first preset voltage threshold as marked cells, and obtain the positions of the marked cells.

[0062] In the embodiment of the present invention: Denote the voltage of the marked cell as V标 Mark the position of the marked battery cell as R 标 The preset current threshold is denoted as I, where I is a current value close to static. When the absolute values of I t1 and I t2 are both less than I, the current is less than the preset current threshold; the first preset voltage threshold is denoted as U1, and U1 can be determined according to the sampling errors of the AFE (battery sampling chip) of different sampled battery cells. It should be noted that the preset current threshold I and the first preset voltage threshold U1 can both be set with corresponding thresholds according to different application scenarios of different battery packs. Through the big data monitoring platform, according to the voltage mutation of the battery cells under small current or static working conditions, the corresponding battery cells are marked, so as to compare the marked battery cell voltage with the voltages of other battery cells.

[0063] Step S3: Based on the positions of the marked battery cells, determine whether there are two marked battery cells with adjacent positions.

[0064] In the embodiment of the present invention: The big data monitoring platform receives the upload of vehicle battery-related data and, according to the pre-input electrical schematic diagram and the relevant characteristics of the sampling chip, as Figures 2 - 7 shown. In the electrical schematic diagram and the relevant characteristic diagram of the sampled battery cells, the positions of the busbars, the AFE power supply and sampling common line positions are respectively marked, and the positions of the first battery cell and the last battery cell sampled by each AFE, or the battery cells associated therewith, so that according to the current relevant characteristics of the sampled battery cells and the position schematic diagram of sampling failure, after determining the virtual connection of the corresponding sampling line, the change of the battery cell voltage can be judged. Through big data analysis and calculation of vehicle battery-related data, the positions corresponding to the single-cell sampling voltage, the working state and working current of the vehicle.

[0065] Step S4: If there are two marked battery cells with adjacent positions, then determine whether the second voltage difference between the two marked battery cells with adjacent positions is less than or equal to the second preset voltage threshold.

[0066] In the embodiment of the present invention: Locate the positions of the already marked battery cells, determine whether there are two adjacent battery cells both marked. If there are two adjacent battery cells both marked, then continue to determine whether the absolute value of the difference of ΔVt between the two adjacent battery cells is ≤ U2, and U2 is determined according to the consistency error of different battery cells themselves and the sampling error of the AFE, and different settings for each item.

[0067] Step S5: If the second voltage difference is less than or equal to the second preset voltage threshold, then determine that the sampling line between the two marked battery cells with adjacent positions is a virtual connection point.

[0068] In an embodiment of the present invention: If the second voltage difference is less than or equal to the second preset voltage threshold, it is considered that there may be a loose connection in the sampling line between these two battery cells, and the sampling line between the two adjacent marked battery cells is determined as the suspected loose connection point L 虚 , otherwise stop marking these two battery cells.

[0069] Through the above embodiments, when the sampling line of the battery pack has a loose connection, the contact resistance at the corresponding contact position will inevitably increase, and the increase in the contact resistance will cause the sampling voltage to decrease. Therefore, by obtaining the first voltage difference of the sampling battery cells in the battery pack, the loose connection can be judged through the voltage change, and the sampling battery cells that meet the conditions of both current and the first voltage difference are marked, and the positions of the marked battery cells are determined. By gradually judging the positions of the marked battery cells, the specific position of the loose connection point can be judged, so as to realize the early detection of the loose connection situation of the battery pack, avoid the vehicle from being continuously overcharged due to the voltage change caused by the loose connection of the sampling line in the BMS, and effectively detect the loose connection situation of the battery pack.

[0070] In one embodiment, the method further includes:

[0071] Step S31, if there are no two adjacent marked battery cells, judge whether the current marked battery cell is the first battery cell or the last battery cell of the battery pack.

[0072] Step S32, if the current marked battery cell is the first battery cell or the last battery cell of the battery pack, judge whether the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located are in parallel.

[0073] Step S33, if the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located are not in parallel, judge whether there is a copper bar connected to the adjacent position of the current marked battery cell.

[0074] Step S34, if there is no copper bar connected to the adjacent position of the current marked battery cell, determine that the negative sampling line of the first battery cell of the battery pack is broken, and determine that the positive sampling line of the last battery cell of the battery pack is the loose connection point.

[0075] In an embodiment of the present invention: The copper bar is a connecting component inside the battery pack. The copper bar is connected to the conductive main bus bar. On the one hand, it can connect and conduct electricity, and on the other hand, it is convenient for heat dissipation in time to keep the temperature inside the battery module normal.

[0076] If it is determined that there are no two adjacent cells that are both marked, then determine whether the currently marked cell is the first or the last cell for AFE voltage sampling. If so, determine whether the power supply of the AFE where this cell is located is in parallel with the voltage sampling line. If there is a parallel connection, then determine whether all the single cells collected by this AFE are less than the single cell voltage where the AFE is located. If there is no parallel connection, then determine whether there is a connecting copper bar at the adjacent position of the marked cell. If there is a connecting copper bar, then jump to step S331. If there is no connecting copper bar at the adjacent position of the currently marked cell, it is considered that the negative sampling line of the first cell is broken, and the positive sampling line of the last cell may be loosely connected. Record that the negative sampling line of the first cell of the AFE is broken, and determine that the positive sampling line of the last cell is the suspected loose connection point L 虚 。

[0077] It should be noted that if there are no two adjacent marked cells, not only determine whether the currently marked cell is the first or the last cell, but also perform this operation on each marked cell to make judgments on all the marked cells.

[0078] In another embodiment, the method further includes:

[0079] Step S331, if there is a copper bar connected at the adjacent position of the currently marked cell, then determine whether the currently marked cell is the cell where the negative sampling line of the copper bar is located.

[0080] Step S332, if the currently marked cell is the cell where the negative sampling line of the copper bar is located, then determine whether the currently marked cell is the first sampled cell of the battery sampling chip;

[0081] Step S333, if the currently marked cell is the first sampled cell of the battery sampling chip, then determine that the negative sampling line of the copper bar and the negative sampling line of the currently marked cell are loose connection points.

[0082] In the embodiment of the present invention: Locate the positions of the already marked cells. If there are no two adjacent cells that are both marked, then determine whether there is a connecting copper bar at the adjacent position of the marked cell. If so, determine whether the currently marked cell is the cell where the negative sampling line of the copper bar is located. If so, continue to determine whether this cell is the first sampled cell of the AFE. If so, it is considered that the negative sampling line of the copper bar and the negative sampling line of the first cell of the AFE may both be loosely connected. Record the negative sampling line of the copper bar and the negative sampling line of the first cell of the AFE as the suspected loose connection point L 虚 。

[0083] By determining whether the currently marked cell is the cell where the negative sampling line of the copper bar is located, the specific position of the loosely connected sampling line is further narrowed down to improve the accuracy of the loose connection point position.

[0084] In another embodiment, the method further includes:

[0085] Step S334, if the currently marked battery cell is not the first sampled battery cell of the battery sampling chip, determine that the negative sampling line of the copper bar is a virtual contact point.

[0086] In the embodiment of the present invention: If the battery cell is not the first sampled battery cell of the AFE, it is considered that there may be a virtual connection in the negative sampling line of the copper bar, and record the negative sampling line of the copper bar as a suspected virtual connection point L 虚 . When it is determined that the currently marked battery cell is not the first sampled battery cell of the battery sampling chip, determine the specific position of the virtual contact point to improve the accuracy of the position of the virtual contact point.

[0087] In another embodiment, the method further includes:

[0088] Step S3311, if the currently marked battery cell is the battery cell where the positive sampling line of the copper bar is located, determine whether the currently marked battery cell is the last sampled battery cell of the battery sampling chip.

[0089] Step S3312, if the currently marked battery cell is the last sampled battery cell of the battery sampling chip, determine that the positive sampling line of the copper bar and the positive sampling line of the currently marked battery cell are virtual contact points.

[0090] In the embodiment of the present invention: Locate the positions of the already marked battery cells. If it is determined that there are no two adjacent battery cells that are both marked, determine whether the adjacent position of the currently marked battery cell is connected to the copper bar. If so, determine whether the currently marked battery cell is the battery cell where the positive sampling of the copper bar is located. If so, continue to determine whether the battery cell is the last sampled battery cell of the AFE. If so, it is considered that there may be virtual connections in both the positive sampling line of the copper bar and the positive sampling line of the last battery cell of the AFE, and record the positive sampling line of the copper bar and the positive sampling line of the last battery cell of the AFE as suspected virtual connection points L 虚 .

[0091] If the currently marked battery cell is the battery cell where the positive sampling line of the copper bar is located, continue to determine whether the specific position of the currently marked battery cell is the last sampled battery cell of the battery sampling chip. After determining the specific position of the currently marked battery cell, determine the specific position of the currently marked battery cell as the virtual contact point, so as to improve the accuracy of the position of the virtual contact point.

[0092] In another embodiment, the method further includes:

[0093] Step S3313, if the currently marked battery cell is not the last sampled battery cell of the battery sampling chip, determine that the positive sampling line of the copper bar is a virtual contact point.

[0094] In the embodiment of the present invention: if the battery cell is not the last battery cell of the AFE, it is considered that the copper busbar positive electrode sampling line may have a virtual connection, and the copper busbar positive electrode sampling line is recorded as a suspected virtual connection point L. When the current marked battery cell is not the last sampled battery cell of the battery sampling chip, the specific position of the virtual connection point is determined to judge a variety of virtual connection situations, and the virtual connection point position is reduced in turn to improve the accuracy of the virtual connection point position.

[0095] Eliminate the cells associated with the marked sampling points at the above positions and the cells associated with the confirmed single cell voltage sampling lines being open, shorted to ground, or shorted to power.

[0096] In another embodiment, the method further comprises:

[0097] Step S61, obtaining a third voltage difference between the marked battery cell and the normal battery cell.

[0098] Step S62: if the third voltage difference is less than the third preset voltage threshold, it is determined whether the voltage of the marked cell is always less than the preset value within a set time period when the battery pack is being charged or discharged.

[0099] Step S63: If the voltage of the marked cell is always less than a preset value within a set time period when the battery pack is being charged or discharged, a warning is issued for the virtual contact.

[0100] In the embodiment of the present invention: the third voltage difference between the marked battery cell and the normal battery cell is recorded as ΔV 标 , where V 标 -V 1 =ΔV 标 1. V 标 -V 2 =ΔV 标 2……V 标 -V n =ΔV 标 n. The duration is set to Y days, and the value of Y can be changed according to the actual application scenario of the battery pack. The preset value can be a normal voltage value or other voltage values, which are not limited here.

[0101] Among them, normal cells refer to cells other than the cells associated with the sampling points marked in the above steps and the cells associated with the confirmed open circuit or short circuit of the single cell voltage sampling line. Based on the comparison data and the change of the single cell voltage under different working conditions, the location of the sampling virtual contact point is confirmed through the big data early warning platform, and the specific virtual contact location is pushed to the after-sales personnel, and it is detected whether the single cell has any abnormality. If an abnormality occurs, the owner is notified in time for repair.

[0102] Through the above embodiments, by judging various possible situations of virtual contacts and successively judging the positions of virtual contacts, the range of virtual contacts is gradually narrowed to determine the final position of virtual contacts, so as to improve the accuracy of virtual contacts.

[0103] Among them, the third preset voltage threshold is X, and the value of X is close to 0 or negative. If the third voltage difference ΔV 标 ≥ the third preset voltage threshold X, stop marking the battery cell.

[0104] If the third voltage difference ΔV 标 < the third preset voltage threshold X, continue to judge whether the voltage of the marked battery cell always remains low when the vehicle where the battery pack is located is charging or discharging, that is, whether it is always less than the third preset voltage threshold X and lasts for Y days. If the voltage of the marked battery cell always remains low and lasts for Y days when the vehicle where the battery pack is located is charging or discharging, give a warning about the virtual contact.

[0105] Among them, for warning about the virtual contact, the position of the virtual contact can be sent to after-sales personnel to facilitate the after-sales personnel to remind the vehicle owner to go to the automobile sales service shop for repair as soon as possible, or it can also be sent to the vehicle owner to facilitate the vehicle owner to go to the automobile sales service shop for repair by himself.

[0106] Further, the method further includes:

[0107] Step S71, if ΔV 标 are all < X, judge whether the marked battery cell accidentally has its voltage transiently greater than U3 and then immediately recovers during the driving of the vehicle where the battery pack is located, and lasts for Y days. If the marked battery cell accidentally has its voltage transiently greater than U3 and then immediately recovers during the driving of the vehicle where the battery pack is located, and lasts for Y days, give a warning about the virtual contact, so as to enable the vehicle owner to drive safely when there is no safety accident during vehicle driving, give an early warning about the safety accident before the occurrence of a safety accident, reduce the possibility of safety accidents such as thermal runaway, and give a warning about the virtual contact when the accidental voltage changes, so as to remind the vehicle owner or after-sales personnel.

[0108] Step S72, if ΔV 标 are all < X, continue to judge whether the marked battery cell has a voltage fluctuation frequency that is Z% greater than that of other battery cells and a duty cycle exceeding W% under the same current, and lasts for Y days. Among them, other battery cells are all single battery cells except those with the open circuit, short circuit to ground, or short circuit to power of the confirmed single battery voltage sampling line and the marked battery cells. If the marked battery cell has a voltage fluctuation frequency that is Z% greater than that of other battery cells and a duty cycle exceeding W% under the same current, and lasts for Y days, give a warning about the virtual contact, so as to give a warning about the virtual contact when the voltage of the marked battery cell fluctuates, so as to remind the vehicle owner or after-sales personnel.

[0109] Step S73, if ΔV 标 are all < X and meet the project passive equalization activation condition, the passive equalization will convert the excess power in the battery into heat energy through the energy-consuming element for consumption, thereby improving the inconsistency of voltage and power between battery cells. When it is detected that the position cell of the marked cell changes slowly from the lowest position to the medium or highest position, that is, the monomer voltage ranking rises by N positions, the virtual contact point will be warned to remind the vehicle owner or after-sales personnel when the position of the marked cell changes.

[0110] In summary, if ΔV 标 are all < X and meet any of the following conditions:

[0111] (1) Whether the marked cell always remains low during vehicle charging or discharging;

[0112] (2) The voltage fluctuation frequency of the marked cell is Z% greater than that of other cells, and the working cycle ratio exceeds W%;

[0113] (3) The voltage of the marked cell transiently decreases > U3 during driving and then immediately recovers.

[0114] Among them, the real-time voltage of the battery at the marked position + the previous memory ΔV * k ≥ the set maximum overcharge voltage, where the k value can be revised according to the system error detected subsequently. Then the suspected position L marked in the above steps 虚 is changed to confirm the virtual connection position of the sampling line and push it to the after-sales personnel, and let the after-sales personnel remind the vehicle owner to go to the automobile sales service store for repair as soon as possible.

[0115] It should be noted that the changes of the parameters Y, Z, W, and N vary with the application scenario of the battery pack.

[0116] Based on the same inventive concept, the present invention also provides a detection system for virtual connection of a battery sampling line.

[0117] Figure 8 is a structural block diagram of a detection system for virtual connection of a battery sampling line proposed according to an exemplary embodiment. As Figure 8 shown, the system includes:

[0118] The first acquisition module 1 is used to acquire the current and the first voltage difference of each sampling cell in the battery pack within a preset time. For specific content, refer to the relevant description of step S1 above, and details will not be elaborated here.

[0119] The second acquisition module 2 is configured to determine the sampled battery cells with a current less than a preset current threshold and a first voltage difference greater than or equal to a first preset voltage threshold as marked battery cells, and acquire the positions of the marked battery cells. For specific content, refer to the relevant description of step S2 above, and details will not be elaborated here.

[0120] The first judgment module 3 is configured to judge whether there are two adjacent marked battery cells based on the positions of the marked battery cells. For specific content, refer to the relevant description of step S3 above, and details will not be elaborated here.

[0121] The second judgment module 4 is configured to, if there are two adjacent marked battery cells, judge whether the second voltage difference between the two adjacent marked battery cells is less than or equal to a second preset voltage threshold. For specific content, refer to the relevant description of step S4 above, and details will not be elaborated here.

[0122] The first determination module 5 is configured to, if the second voltage difference is less than or equal to the second preset voltage threshold, determine the sampling line between the two adjacent marked battery cells as a virtual connection point. For specific content, refer to the relevant description of step S5 above, and details will not be elaborated here.

[0123] In one embodiment, the system further includes:

[0124] The third judgment module is configured to, if there are no two adjacent marked battery cells, judge whether the current marked battery cell is the first battery cell or the last battery cell of the battery pack. For specific content, refer to the relevant description of step S31 above, and details will not be elaborated here.

[0125] The fourth judgment module is configured to, if the current marked battery cell is the first battery cell or the last battery cell of the battery pack, judge whether the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located are in parallel. For specific content, refer to the relevant description of step S32 above, and details will not be elaborated here.

[0126] The fifth judgment module is configured to, if the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located are not in parallel, judge whether a copper bar is connected to the adjacent position of the current marked battery cell. For specific content, refer to the relevant description of step S33 above, and details will not be elaborated here.

[0127] The second determination module is configured to, if no copper bar is connected to the adjacent position of the current marked battery cell, determine that the negative sampling line of the first battery cell of the battery pack is broken, and determine that the positive sampling line of the last battery cell of the battery pack is a virtual connection point. For specific content, refer to the relevant description of step S34 above, and details will not be elaborated here.

[0128] In one embodiment, the system further includes:

[0129] The sixth judgment module is used to judge whether the currently marked battery cell is the battery cell where the negative sampling line of the copper bar is located if a copper bar is connected to the adjacent position of the currently marked battery cell. For specific content, refer to the relevant description in step S331 above, and details will not be elaborated here.

[0130] The seventh judgment module is used to judge whether the currently marked battery cell is the first sampled battery cell of the battery sampling chip if the currently marked battery cell is the battery cell where the negative sampling line of the copper bar is located. For specific content, refer to the relevant description in step S332 above, and details will not be elaborated here.

[0131] The third determination module is used to determine that the negative sampling line of the copper bar and the negative sampling line of the currently marked battery cell are virtual connection points if the currently marked battery cell is the first sampled battery cell of the battery sampling chip. For specific content, refer to the relevant description in step S333 above, and details will not be elaborated here.

[0132] In one embodiment, the system further includes:

[0133] The fourth determination module is used to determine that the negative sampling line of the copper bar is a virtual connection point if the currently marked battery cell is not the first sampled battery cell of the battery sampling chip. For specific content, refer to the relevant description in step S334 above, and details will not be elaborated here.

[0134] In one embodiment, the system further includes:

[0135] The eighth judgment module is used to judge whether the currently marked battery cell is the last sampled battery cell of the battery sampling chip if the currently marked battery cell is the battery cell where the positive sampling line of the copper bar is located. For specific content, refer to the relevant description in step S3311 above, and details will not be elaborated here.

[0136] The fifth determination module is used to determine that the positive sampling line of the copper bar and the positive sampling line of the currently marked battery cell are virtual connection points if the currently marked battery cell is the last sampled battery cell of the battery sampling chip. For specific content, refer to the relevant description in step S3312 above, and details will not be elaborated here.

[0137] In one embodiment, the system further includes:

[0138] The sixth determination module is used to determine that the positive sampling line of the copper bar is a virtual connection point if the currently marked battery cell is not the last sampled battery cell of the battery sampling chip. For specific content, refer to the relevant description in step S3313 above, and details will not be elaborated here.

[0139] In one embodiment, the system further includes:

[0140] The third acquisition module is used to acquire the third voltage difference between the marked battery cell and the normal battery cell. For specific content, refer to the relevant description in step S61 above, and details will not be elaborated here.

[0141] A ninth determination module, configured to determine whether the voltage of the marked battery cell is always less than a preset value within a set duration when the battery pack is charging or discharging if a third voltage difference is less than a third preset voltage threshold. For specific content, refer to the relevant description in step S62 above, and details will not be elaborated here.

[0142] An early warning module, configured to give an early warning about a virtual connection point if the voltage of the marked battery cell is always less than a preset value within a set duration when the battery pack is charging or discharging. For specific content, refer to the relevant description in step S63 above, and details will not be elaborated here.

[0143] For specific limitations and beneficial effects of the above detection system based on virtual connection of battery sampling lines, refer to the limitations on the detection method of virtual connection of battery sampling lines in the above text, and details will not be elaborated here. Each of the above modules can be implemented in whole or in part by software, hardware, and their combinations. Each of the above modules can be embedded in a processor in a computer device in hardware form or be independent of it, or can be stored in a memory in a computer device in software form, so as to facilitate the processor to call and execute the operations corresponding to each of the above modules.

[0144] Figure 9 is a schematic diagram of the hardware structure of a computer device according to an exemplary embodiment. As Figure 9 shown, the device includes one or more processors 910 and a memory 920. The memory 920 includes persistent memory, volatile memory, and a hard disk. Figure 9 Here, one processor 910 is taken as an example. The device may further include: an input device 990 and an output device 940.

[0145] The processor 910, the memory 920, the input device 990, and the output device 940 may be connected through a bus or other means. Figure 9 Here, connection through a bus is taken as an example.

[0146] The processor 910 may be a central processing unit (CPU). The processor 910 may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. chips, or combinations of the above types of chips. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0147] The memory 920, as a non-transitory computer-readable storage medium, includes persistent memory, volatile memory, and a hard disk, and can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as program instructions / modules corresponding to the service management method in the embodiments of the present application. The processor 910 executes various functional applications and data processing of the server by running the non-transitory software programs, instructions, and modules stored in the memory 920, that is, implements any one of the above-mentioned methods for detecting virtual connection of the battery sampling line.

[0148] The memory 920 may include a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function; the data storage area can store data used according to needs, etc. In addition, the memory 920 may include high-speed random access memory, and may also include non-transitory memory, such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some embodiments, the memory 920 may optionally include a memory remotely disposed relative to the processor 910, and these remote memories can be connected to the data processing device through a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an enterprise intranet, a local area network, a mobile communication network, and combinations thereof.

[0149] The input device 990 can receive input digital or character information, and generate key signal inputs related to user settings and function controls. The output device 940 may include a display device such as a display screen.

[0150] One or more modules are stored in the memory 920, and when executed by one or more processors 910, they execute the method for detecting virtual connection of the battery sampling line as Figure 1 shown.

[0151] The above product can execute the method provided by the embodiments of the present invention, and has functional modules and beneficial effects corresponding to the execution method. Technical details not described in detail in this embodiment can be specifically referred to the relevant descriptions in the embodiments as Figure 1 shown.

[0152] The embodiments of the present invention also provide a non-transitory computer storage medium, and the computer storage medium stores computer-executable instructions, and the computer-executable instructions can execute the methods in any of the above method embodiments. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (abbreviation: HDD), or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above types of memories.

[0153] Obviously, the above embodiments are merely examples for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A method for detecting loose connection of battery sampling lines, characterized in that, the method includes: Obtain the current and the first voltage difference of each sampled battery cell in the battery pack within a preset time; specifically, obtain the current I 1 at time t 2 and I t1 of each sampled battery cell in the battery pack at time t t2 , obtain the voltages Vn 1 and Vn 2 of each sampled battery cell in the battery pack at time t t1 and t t2 , and calculate the first voltage difference ΔVn = Vn t1 - Vn t2 ; When the current is less than a preset current threshold, that is, when the absolute values of I t1 and I t2 are both less than the current value I close to static, and the first voltage difference is greater than or equal to the first preset voltage threshold, the sampled battery cell is determined as a marked battery cell, and the position of the marked battery cell is obtained; Based on the positions of the marked battery cells, determine whether there are two marked battery cells adjacent in position; If there are two marked battery cells adjacent in position, then determine whether the absolute value of the difference between the ΔVn of the two marked battery cells adjacent in position, that is, the second voltage difference, is less than or equal to the second preset voltage threshold; If the second voltage difference is less than or equal to the second preset voltage threshold, then determine that the sampling line between the two marked battery cells adjacent in position is a loose connection point.

2. The method according to claim 1, characterized in that, the method further includes: If there are no two marked battery cells adjacent in position, then determine whether the current marked battery cell is the first battery cell or the last battery cell of the battery pack; If the current marked battery cell is the first battery cell or the last battery cell of the battery pack, then determine whether the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located are in parallel; If the power supply line and the voltage sampling line of the battery sampling chip where the current marked battery cell is located are not in parallel, then determine whether there is a copper bar connected to the adjacent position of the current marked battery cell; If there is no copper bar connected to the adjacent position of the current marked battery cell, then determine that the negative sampling line of the first battery cell of the battery pack is broken, and determine that the positive sampling line of the last battery cell of the battery pack is a loose connection point.

3. The method according to claim 2, characterized in that, the method further includes: If there is a copper bar connected to the adjacent position of the current marked battery cell, then determine whether the current marked battery cell is the battery cell where the negative sampling line of the copper bar is located; If the current marked battery cell is the battery cell where the negative sampling line of the copper bar is located, then determine whether the current marked battery cell is the first sampling battery cell of the battery sampling chip; If the current marked battery cell is the first sampling battery cell of the battery sampling chip, then determine that the negative sampling line of the copper bar and the negative sampling line of the current marked battery cell are loose connection points.

4. The method according to claim 3, characterized in that, the method further includes: If the current marked battery cell is not the first sampling battery cell of the battery sampling chip, then determine that the negative sampling line of the copper bar is a loose connection point.

5. The method according to claim 3, characterized in that, the method further includes: If the current marked battery cell is the battery cell where the positive sampling line of the copper bar is located, then determine whether the current marked battery cell is the last sampling battery cell of the battery sampling chip; If the current marked battery cell is the last sampling battery cell of the battery sampling chip, then determine that the positive sampling line of the copper bar and the positive sampling line of the current marked battery cell are loose connection points.

6. The method according to claim 5, characterized in that, the method further includes: If the current marked battery cell is not the last sampling battery cell of the battery sampling chip, then determine that the positive sampling line of the copper bar is a loose connection point.

7. The method according to any one of claims 1-6, characterized in that, the method further includes: Obtain the third voltage difference between the marked battery cell and the normal battery cell; If the third voltage difference is less than the third preset voltage threshold, then determine whether the voltage of the marked battery cell is always less than the preset value within the set time when the battery pack is charging or discharging; If the voltage of the marked battery cell is always less than the preset value within the set duration during battery pack charging or discharging, a warning is given for the virtual contact point.

8. A detection system for virtual connection of a battery sampling line, characterized in that, the system includes: The first acquisition module is used to obtain the current and the first voltage difference of each sampled battery cell in the battery pack within a preset time; specifically, to obtain the current and the first voltage difference of each sampled battery cell in the battery pack within a preset time. 1 Time and t 2 The current I at the moment t1 and I t2 , obtain the sampling cells in the battery pack at t 1 Time and t 2 Voltage Vn at the moment t1 and Vn t2 , and calculate the first voltage difference ΔVn = Vn t1 -Vn t2 ; A second acquisition module, configured to determine a sampled battery cell with a current less than a preset current threshold, that is, when the absolute values of I t1 and I t2 are both less than the current value I close to static, and the first voltage difference is greater than or equal to a first preset voltage threshold, as a marked battery cell, and obtain the position of the marked battery cell; A first judgment module, configured to judge whether there are two adjacent marked battery cells based on the positions of the marked battery cells; A second judgment module, configured to, if there are two adjacent marked battery cells, judge whether the absolute value of the difference between ΔVn of the two adjacent marked battery cells, that is, the second voltage difference, is less than or equal to a second preset voltage threshold; A determination module, configured to, if the second voltage difference is less than or equal to the second preset voltage threshold, determine that the sampling line between the two adjacent marked battery cells is a virtual contact point.

9. A computer device, characterized in that, it includes a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to execute the detection method for virtual connection of a battery sampling line according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, the computer-readable storage medium stores computer instructions, and the computer instructions are used to cause the computer to execute the detection method for virtual connection of a battery sampling line according to any one of claims 1-7.

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