Method, device and equipment for determining the location of a leaking cell in a battery pack

Abstract

The application provides a method, device and equipment for determining the position of a leaking battery cell in a battery pack, wherein the method comprises the following steps: measuring the total voltage of the battery pack as a first voltage value by a first voltmeter and a second voltmeter connected in series; connecting the total positive electrode of the battery pack and the shell of the battery pack by two probes of the first voltmeter to obtain a second voltage value, and connecting the total negative electrode of the battery pack and the shell of the battery pack by two probes of the second voltmeter to obtain a third voltage value; if the absolute value of the difference between half of the first voltage value and the second voltage value is greater than a first preset value, then performing a ratio operation on the second voltage value and the rated voltage value of a single battery cell in the battery pack to obtain a first ratio value, and determining the position of the leaking battery cell in the battery pack according to the first ratio value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery energy storage, and in particular to a method and device for determining the location of a leaking cell in a battery pack. BACKGROUND

[0002] In the prior art, it is difficult to detect the specific leakage point in a battery pack. If leakage occurs in the battery pack, it will cause harm to personnel safety. Although some manufacturers have proposed methods for detecting specific faults of intermediate leakage in a battery pack, the detection process is complex and the detection cost is high. SUMMARY

[0003] To solve the above technical problems, the present application provides a method and device for determining the location of a leaking cell in a battery pack. In the present application, the total voltage of the battery pack is measured by a first voltmeter and a second voltmeter connected in series as a first voltage value; two probes of the first voltmeter are connected to the total positive electrode of the battery pack and the shell of the battery pack to obtain a second voltage value, and two probes of the second voltmeter are connected to the total negative electrode of the battery pack and the shell of the battery pack to obtain a third voltage value; if the absolute value of the difference between half of the first voltage value and the second voltage value is greater than a first preset value, a first ratio is obtained by ratio operation of the second voltage value and the rated voltage value of a single cell in the battery pack, and the location of the leaking cell in the battery pack is determined according to the first ratio.

[0004] In a first aspect, the present application provides a method for determining the location of a leaking cell in a battery pack, comprising:

[0005] measuring the total voltage of the battery pack by a first voltmeter and a second voltmeter connected in series as a first voltage value;

[0006] connecting two probes of the first voltmeter to the total positive electrode of the battery pack and the shell of the battery pack to obtain a second voltage value, and connecting two probes of the second voltmeter to the total negative electrode of the battery pack and the shell of the battery pack to obtain a third voltage value;

[0007] if the absolute value of the difference between half of the first voltage value and the second voltage value is greater than a first preset value, a first ratio is obtained by ratio operation of the second voltage value and the rated voltage value of a single cell in the battery pack, and the location of the leaking cell in the battery pack is determined according to the first ratio; or,

[0008] if the absolute value of the difference between half of the first voltage value and the third voltage value is greater than a first preset value, a second ratio is obtained by ratio operation of the third voltage value and the rated voltage value of a single cell in the battery pack, and the location of the leaking cell in the battery pack is determined according to the second ratio.

[0009] In an alternative embodiment, the N cells in the battery pack are connected in series in turn, the first cell physically connected to the total negative electrode of the battery pack is numbered 1, the second cell connected in series with the first cell in the battery pack is numbered 2, and the numbering of the N cells in the battery pack is completed in turn based on the series connection order of the cells, wherein the first cell physically connected to the total positive electrode of the battery pack is numbered N;

[0010] The position of the cell with leakage in the battery pack is determined according to the first ratio, and specifically includes:

[0011] The first cell physically connected to the total positive electrode of the battery pack is determined as the starting point of counting based on the first ratio, and the first ratio of cells with leakage is determined based on the series connection order of the N cells in the battery pack, wherein the first ratio is less than or equal to N.

[0012] In an alternative embodiment, the N cells in the battery pack are connected in series in turn, the first cell physically connected to the total negative electrode of the battery pack is numbered 1, the second cell connected in series with the first cell in the battery pack is numbered 2, and the numbering of the N cells in the battery pack is completed in turn based on the series connection order of the cells, wherein the first cell physically connected to the total positive electrode of the battery pack is numbered N;

[0013] The position of the cell with leakage in the battery pack is determined according to the second ratio, and specifically includes:

[0014] The third ratio is obtained by increasing the second ratio by 1, and the first cell physically connected to the total negative electrode of the battery pack is determined as the starting point of counting, and the third ratio of cells with leakage is determined based on the series connection order of the N cells in the battery pack, wherein the third ratio is less than or equal to N.

[0015] In an alternative embodiment, the detection circuit for detecting the leakage of the battery pack includes a first measurement circuit for detecting the leakage current value of the cell in the battery pack, and a second measurement circuit connected in series with the first side of the first measurement circuit, wherein the second side of the first measurement circuit is connected to the shell of the battery pack; wherein

[0016] The first measurement circuit includes a first measurement branch, a second measurement branch, and a third voltmeter, wherein

[0017] The first measurement branch includes a first resistor and a first switch, and the second measurement branch includes a second resistor and a second switch; the first measurement branch and the second measurement branch are connected in parallel, and the third voltmeter is used to measure the voltage value of the first resistor in the first measurement branch and the voltage value of the second resistor in the second measurement branch, respectively, wherein the resistance value of the first resistor is greater than the resistance value of the second resistor;

[0018] The second measurement circuit includes a third resistor and a third switch connected in series with each other; the third switch is connected to the total positive electrode of the battery pack, and the third resistor is connected to the first measurement circuit.

[0019] Before connecting the total positive pole of the battery pack and the shell of the battery pack by two probes of the first voltmeter to obtain a second voltage value, and connecting the total negative pole of the battery pack and the shell of the battery pack by two probes of the second voltmeter to obtain a third voltage value, the position determination method further comprises:

[0020] When the first switch and the third switch are turned on, and the second switch is turned off, so that the first measurement branch and the second measurement circuit are turned on, and the second measurement branch is turned off, the voltage value of the first resistor measured by the third voltmeter is a fourth voltage value, and the first current value of the first resistor is obtained by calculation according to the obtained resistance value of the first resistor, wherein the third resistor is used for current limiting of the turned-on first measurement branch and the second measurement circuit;

[0021] When the second switch and the third switch are turned on, and the first switch is turned off, so that the first measurement branch is turned off, and the second measurement branch and the second measurement circuit are turned on, the voltage value of the second resistor measured by the third voltmeter is a fifth voltage value, and the second current value of the second resistor is obtained according to the obtained resistance value of the second resistor, wherein the second current value is greater than or equal to the first current value, and the third resistor is also used for current limiting of the turned-on second measurement branch and the second measurement circuit;

[0022] If the absolute value of the difference between the second current value and the first current value is less than or equal to a second preset value, the second current value is taken as the leakage current value of the battery cell in the battery pack;

[0023] It is judged whether the leakage current value is less than or equal to a third preset value, and if the leakage current value is greater than the third preset value, it is determined that the battery pack leaks electricity.

[0024] In an optional implementation, a detection circuit for detecting leakage of a battery pack comprises: a first measurement circuit for detecting a leakage current value of a battery cell in the battery pack, and a second measurement circuit connected in series with a first side of the first measurement circuit, wherein a second side of the first measurement circuit is connected to a shell of the battery pack;

[0025] The first measurement circuit comprises: a first measurement branch, a second measurement branch, and a third voltmeter, wherein,

[0026] The first measurement branch comprises a first resistor and a first switch, and the second measurement branch comprises a second resistor and a second switch; the first measurement branch and the second measurement branch are connected in parallel, and the third voltmeter is used for measuring a voltage value of the first resistor in the first measurement branch and a voltage value of the second resistor in the second measurement branch, respectively, wherein the resistance value of the first resistor is greater than the resistance value of the second resistor;

[0027] The second measuring circuit comprises a fourth resistor and a fourth switch connected in series; the fourth switch is connected to the total negative pole of the battery pack, and the fourth resistor is connected to the first measuring circuit;

[0028] Before the total positive pole of the battery pack and the shell of the battery pack are connected by two probes of the first voltmeter to obtain a second voltage value, and the total negative pole of the battery pack and the shell of the battery pack are connected by two probes of the second voltmeter to obtain a third voltage value, the position determining method further comprises:

[0029] When the first switch and the fourth switch are turned on, the second switch is turned off, so that the first measuring branch and the second measuring circuit are turned on, and the second measuring branch is turned off, the voltage value of the first resistor measured by the third voltmeter is a fourth voltage value, and the first current value of the first resistor is obtained by calculation according to the obtained resistance value of the first resistor; wherein the fourth resistor is used for current limiting of the turned-on first measuring branch and second measuring circuit;

[0030] When the second switch and the fourth switch are turned on, the first switch is turned off, so that the first measuring branch is turned off, and the second measuring branch and the second measuring circuit are turned on, the voltage value of the second resistor measured by the third voltmeter is a fifth voltage value, and the second current value of the second resistor is obtained according to the obtained resistance value of the second resistor; wherein the second current value is greater than or equal to the first current value, and the fourth resistor is also used for current limiting of the turned-on second measuring branch and second measuring circuit;

[0031] If the absolute value of the difference between the second current value and the first current value is less than or equal to a second preset value, the second current value is taken as the leakage current value of the battery cell in the battery pack;

[0032] It is judged whether the leakage current value is less than or equal to a third preset value, if the leakage current value is greater than the third preset value, it is determined that the battery pack leaks electricity.

[0033] In an optional implementation, the two probes of the first voltmeter comprise a first probe and a second probe, and the two probes of the second voltmeter comprise a third probe and a fourth probe;

[0034] The total voltage of the battery pack is measured by the first voltmeter and the second voltmeter connected in series, and specifically comprises:

[0035] The first probe of the first voltmeter is connected to the total positive pole of the battery pack, the second probe of the first voltmeter is connected to the third probe of the second voltmeter, and the fourth probe of the second voltmeter is connected to the total negative pole of the battery pack, so as to realize the series connection of the first voltmeter and the second voltmeter and measure the total voltage of the battery pack, and obtain the total voltage of the battery pack as the first voltage value; wherein the second probe and the third probe are connected together and connected to the shell of the battery pack.

[0036] In an alternative embodiment, the first probe of the first voltmeter is connected to the total positive pole of the battery pack through a fifth switch, and the fourth probe of the second voltmeter is connected to the total negative pole of the battery pack through a sixth switch.

[0037] The total voltage of the battery pack is measured by the first voltmeter and the second voltmeter connected in series, specifically comprising:

[0038] The first probe of the first voltmeter is connected to the fifth switch, the second probe of the first voltmeter is connected to the third probe of the second voltmeter, and the fourth probe of the second voltmeter is connected to the sixth switch, and the total voltage of the battery pack is measured by the first voltmeter and the second voltmeter connected in series, to obtain the first voltage value of the total voltage of the battery pack.

[0039] In an alternative embodiment, the two probes of the first voltmeter include a first probe and a second probe, and the two probes of the second voltmeter include a third probe and a fourth probe.

[0040] The first probe of the first voltmeter is connected to the total positive pole of the battery pack through a fifth switch, and the fourth probe of the second voltmeter is connected to the total negative pole of the battery pack through a sixth switch, the second probe of the first voltmeter is connected to the shell of the battery pack through a seventh switch, and the third probe of the second voltmeter is also connected to the shell of the battery pack through the seventh switch.

[0041] The two probes of the first voltmeter are connected to the total positive pole of the battery pack and the shell of the battery pack respectively to obtain a second voltage value, and the two probes of the second voltmeter are connected to the total negative pole of the battery pack and the shell of the battery pack respectively to obtain a third voltage value, specifically comprising:

[0042] The first probe of the first voltmeter is connected to the fifth switch, and the total positive pole of the battery pack is connected through the fifth switch, the second probe of the first voltmeter is connected to the seventh switch, and the shell of the battery pack is connected through the seventh switch to obtain the second voltage value, and the third probe of the second voltmeter is connected to the seventh switch, the shell of the battery pack is connected through the seventh switch, and the fourth probe of the second voltmeter is connected to the sixth switch, the total negative pole of the battery pack is connected through the sixth switch to obtain the third voltage value.

[0043] In a second aspect, the application provides a device for determining the position of a leakage cell in a battery pack, comprising a measurement module, an operation module, and a determination module, wherein,

[0044] The measuring module is configured to measure a total voltage of the battery pack as a first voltage value by a first voltmeter and a second voltmeter connected in series with each other;

[0045] The measuring module is further configured to obtain a second voltage value by connecting a total positive electrode of the battery pack and a shell of the battery pack by two probes of the first voltmeter, and obtain a third voltage value by connecting a total negative electrode of the battery pack and the shell of the battery pack by two probes of the second voltmeter;

[0046] The calculating module is configured to perform a ratio operation on the second voltage value and a rated voltage value of a single cell in the battery pack to obtain a first ratio value, if an absolute value of a difference between a half of the first voltage value and the second voltage value is greater than a first preset value;

[0047] The determining module is configured to determine a position of a cell with a leakage current in the battery pack according to the first ratio value;

[0048] The calculating module is further configured to perform a ratio operation on the third voltage value and the rated voltage value of the single cell in the battery pack to obtain a second ratio value, if an absolute value of a difference between the half of the first voltage value and the third voltage value is greater than the first preset value;

[0049] The determining module is further configured to determine the position of the cell with the leakage current in the battery pack according to the second ratio value.

[0050] In an optional embodiment, the position determining device of the cell with the leakage current in the battery pack further comprises:

[0051] a detection circuit for detecting a leakage current of the battery pack and a judging module; wherein,

[0052] The detection circuit for detecting the leakage current of the battery pack comprises a first measuring circuit for measuring the leakage current of the cell in the battery pack, and a second measuring circuit connected in series with a first side of the first measuring circuit, wherein a second side of the first measuring circuit is connected to a shell of the battery pack; wherein,

[0053] The first measuring circuit comprises a first measuring branch, a second measuring branch, and a third voltmeter, wherein,

[0054] The first measuring branch comprises a first resistor and a first switch, and the second measuring branch comprises a second resistor and a second switch; the first measuring branch and the second measuring branch are connected in parallel, and the third voltmeter is configured to measure a voltage value of the first resistor in the first measuring branch and a voltage value of the second resistor in the second measuring branch, respectively, wherein a resistance value of the first resistor is greater than a resistance value of the second resistor;

[0055] The second measuring circuit comprises a third resistor and a third switch connected in series with each other; the second measuring circuit is connected to a total positive electrode of the battery pack by the third switch, and connected to the first measuring circuit by the third resistor;

[0056] The operation module is further configured to:

[0057] When the first switch and the third switch are turned on and the second switch is turned off, the first measurement branch is connected to the second measurement circuit, and the second measurement branch is disconnected, the third voltmeter measures a fourth voltage value of the first resistor, and a first current value of the first resistor is obtained by calculation according to the obtained resistance value of the first resistor, wherein the third resistor is used for current limiting of the connected first measurement branch and second measurement circuit; and

[0058] When the second switch and the third switch are turned on and the first switch is turned off, the first measurement branch is disconnected, and the second measurement branch is connected to the second measurement circuit, the third voltmeter measures a fifth voltage value of the second resistor, and a second current value of the second resistor is obtained according to the obtained resistance value of the second resistor; wherein the second current value is greater than or equal to the first current value, and the third resistor is further used for current limiting of the connected second measurement branch and second measurement circuit.

[0059] The judgment module is configured to:

[0060] If the absolute value of the difference between the second current value and the first current value is less than or equal to a second preset value, the second current value is taken as the leakage current value of the battery cell in the battery pack.

[0061] It is judged whether the leakage current value is less than or equal to a third preset value, and if the leakage current value is greater than the third preset value, it is determined that the battery pack leaks electricity.

[0062] In a third aspect, the application provides a device for determining the position of a battery cell leaking electricity in a battery pack, a memory and a processor connected to the memory, the memory is used to store application program code, and the processor is configured to call the program code and execute the method for determining the position of a battery cell leaking electricity in a battery pack according to the first aspect.

[0063] The application provides a method, device and equipment for determining the position of a leaking battery cell in a battery pack, wherein the method comprises the following steps: measuring the total voltage of the battery pack as a first voltage value through a first voltmeter and a second voltmeter connected in series; connecting the total positive electrode of the battery pack and the shell of the battery pack through two probes of the first voltmeter to obtain a second voltage value, and connecting the total negative electrode of the battery pack and the shell of the battery pack through two probes of the second voltmeter to obtain a third voltage value; if the absolute value of the difference between half of the first voltage value and the second voltage value is greater than a first preset value, then performing ratio operation on the second voltage value and the rated voltage value of a single battery cell in the battery pack to obtain a first ratio value, and determining the position of the leaking battery cell in the battery pack according to the first ratio value; or if the absolute value of the difference between half of the first voltage value and the third voltage value is greater than the first preset value, then performing ratio operation on the third voltage value and the rated voltage value of a single battery cell in the battery pack to obtain a second ratio value, and determining the position of the leaking battery cell in the battery pack according to the second ratio value. BRIEF DESCRIPTION OF DRAWINGS

[0064] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0065] Figure 1 It is a schematic flow chart of the method for determining the position of a leaking battery cell in a battery pack provided by the application.

[0066] Figure 2 It is a schematic flow chart of the system for determining the position of a leaking battery cell in a battery pack provided by the application.

[0067] Figure 3 It is a schematic diagram of the device for determining the position of a leaking battery cell in a battery pack provided by the application.

[0068] Figure 4 It is a schematic diagram of the device for determining the position of a leaking battery cell in a battery pack provided by the application. DETAILED DESCRIPTION

[0069] The technical solutions in the application will be described clearly and completely in the following with reference to the drawings in the application. Obviously, the described embodiments are some embodiments of the application, but not all the embodiments. Based on the embodiments in the application, all the other embodiments obtained by those skilled in the art without any creative effort are within the protection scope of the application.

[0070] It should be noted that the first, second, third, fourth, sixth, seventh, eighth, ninth in the present application are only used to distinguish different switches, voltmeters, voltage values, current values, preset values, ratios, measurement circuits, measurement branches, resistors, probes, etc., and have no other meanings, which should not limit the protection scope of the present application.

[0071] Referring to Figure 1 , it is a flowchart of a method for determining the position of a battery pack in the present application. As shown in Figure 1 , specifically, the position determination method can include but is not limited to the following steps:

[0072] S101, the total voltage of the battery pack is measured by the first and second voltmeters connected in series as the first voltage value.

[0073] Specifically, when the two probes of the first voltmeter include: the first probe, the second probe; the two probes of the second voltmeter include: the third probe, the fourth probe, the first probe and the second probe can be two different probes on the first voltmeter, and the third probe and the fourth probe can be two different probes on the second voltmeter.

[0074] The total voltage of the battery pack is measured by the first and second voltmeters connected in series as the first voltage value, which can include but is not limited to:

[0075] The first probe of the first voltmeter is connected to the total positive electrode of the battery pack, the second probe of the first voltmeter is connected to the third probe of the second voltmeter, and the fourth probe of the second voltmeter is connected to the total negative electrode of the battery pack, so as to realize the series connection of the first and second voltmeters and measure the total voltage of the battery pack, and obtain the total voltage of the battery pack as the first voltage value; wherein the second probe and the third probe are connected together with the shell of the battery pack. Wherein the first and second voltmeters can be the same type of voltmeter for measuring voltage value.

[0076] Preferably, the first and second voltmeters are connected in series and measure the total voltage of the battery pack to obtain the total voltage of the battery pack as the first voltage value, which can be: the sum of the measurement value of the first voltmeter and the measurement value of the second voltmeter as the total voltage of the battery pack, that is, the first voltage value.

[0077] Optionally, when the first probe of the first voltmeter is connected between the total positive electrode of the battery pack and the fifth switch is provided, and the fourth probe of the second voltmeter is connected between the total negative electrode of the battery pack and the sixth switch is provided,

[0078] The total voltage of the battery pack is measured by the first and second voltmeters connected in series as the first voltage value, which can include but is not limited to:

[0079] The first probe of the first voltmeter is connected to the fifth switch, the total positive pole of the battery pack is connected through the fifth switch, the third probe of the second voltmeter is connected to the second probe of the first voltmeter, and the fourth probe of the second voltmeter is connected to the sixth switch, and the total negative pole of the battery pack is connected through the sixth switch, so that the first voltmeter and the second voltmeter are connected in series, the total voltage of the battery pack is measured, and the total voltage of the battery pack is obtained as the first voltage value. The fifth switch and the sixth switch are two different switches of the same type.

[0080] In S102, the two probes of the first voltmeter are connected to the total positive pole and the shell of the battery pack respectively to obtain a second voltage value, and the two probes of the second voltmeter are connected to the total negative pole and the shell of the battery pack respectively to obtain a third voltage value.

[0081] Specifically, the two probes of the first voltmeter include a first probe and a second probe, and the two probes of the second voltmeter include a third probe and a fourth probe.

[0082] The first probe of the first voltmeter is connected to the total positive pole of the battery pack through the fifth switch, the fourth probe of the second voltmeter is connected to the total negative pole of the battery pack through the sixth switch, the second probe of the first voltmeter is connected to the shell of the battery pack through the seventh switch, and the third probe of the second voltmeter is also connected to the shell of the battery pack through the seventh switch. The seventh switch, the fifth switch and the sixth switch are different switches of the same type.

[0083] In S102, the two probes of the first voltmeter are connected to the total positive pole and the shell of the battery pack respectively to obtain a second voltage value, and the two probes of the second voltmeter are connected to the total negative pole and the shell of the battery pack respectively to obtain a third voltage value.

[0084] The first probe of the first voltmeter is connected to the fifth switch, the total positive pole of the battery pack is connected through the fifth switch, the third probe of the second voltmeter is connected to the seventh switch, the shell of the battery pack is connected through the seventh switch, and the second voltage value is obtained. At the same time, the third probe of the second voltmeter is connected to the seventh switch, the shell of the battery pack is connected through the seventh switch, and the fourth probe of the second voltmeter is connected to the sixth switch, and the total negative pole of the battery pack is connected through the sixth switch to obtain the third voltage value.

[0085] Preferably, the detection circuit for detecting the leakage of the battery pack comprises a first measurement circuit for detecting the leakage current value of the battery cell, and a second measurement circuit connected in series with the first side of the first measurement circuit, wherein the second side of the first measurement circuit is connected to the shell of the battery pack; wherein

[0086] The first measuring circuit comprises a first measuring branch, a second measuring branch and a third voltmeter, wherein,

[0087] The first measuring branch comprises a first resistor and a first switch, and the second measuring branch comprises a second resistor and a second switch; the first measuring branch and the second measuring branch are connected in parallel, and the third voltmeter is used to measure the voltage value of the first resistor in the first measuring branch and the voltage value of the second resistor in the second measuring branch, respectively, wherein the resistance of the first resistor is greater than the resistance of the second resistor; the third voltmeter can be a voltmeter of the same type as the first voltmeter and the second voltmeter, which can measure the voltage value of the resistor.

[0088] When the second measuring circuit comprises a third resistor and a third switch connected in series with each other; the third switch is connected to the total positive electrode of the battery pack, and the third resistor is connected to the first measuring circuit;

[0089] Before the two probes of the first voltmeter are connected to the total positive electrode of the battery pack and the shell of the battery pack to obtain a second voltage value, and the two probes of the second voltmeter are connected to the total negative electrode of the battery pack and the shell of the battery pack to obtain a third voltage value, the following steps can also be included:

[0090] When the first switch and the third switch are turned on, and the second switch is turned off, so that the first measuring branch is turned on and the second measuring branch is turned off, the voltage value of the first resistor measured by the third voltmeter is a fourth voltage value, and the first current value of the first resistor is obtained by calculation according to the obtained resistance value of the first resistor, wherein the third resistor is used to limit the current of the turned-on first measuring branch and the second measuring circuit; or,

[0091] When the second switch and the third switch are turned on, and the first switch is turned off, so that the first measuring branch is turned off and the second measuring branch is turned on, the voltage value of the second resistor measured by the third voltmeter is a fifth voltage value, and the second current value of the second resistor is obtained according to the obtained resistance value of the second resistor; wherein the second current value is greater than or equal to the first current value, and the third resistor is also used to limit the current of the turned-on second measuring branch and the second measuring circuit;

[0092] If the absolute value of the difference between the second current value and the first current value is less than or equal to a second preset value, the second current value is taken as the leakage current value of the battery cell in the battery pack, wherein the second preset value can be 0.001 A;

[0093] It is judged whether the leakage current value is less than or equal to a third preset value, and if the leakage current value is greater than the third preset value, it is determined that the battery pack leaks. Preferably, the value of the third preset value can be 0.02 A.

[0094] Preferably, the detection circuit for detecting the leakage current of the battery pack comprises: a first measurement circuit for detecting the leakage current value of the battery cell in the battery pack, and a second measurement circuit connected in series with the first side of the first measurement circuit, wherein the second side of the first measurement circuit is connected to the shell of the battery pack.

[0095] The first measurement circuit can comprise, but is not limited to: a first measurement branch, a second measurement branch, and a third voltmeter, wherein,

[0096] The first measurement branch comprises a first resistor and a first switch, and the second measurement branch comprises a second resistor and a second switch; the first measurement branch and the second measurement branch are connected in parallel; the third voltmeter is used to measure the voltage value of the first resistor in the first measurement branch and the voltage value of the second resistor in the second measurement branch, respectively, wherein the resistance value of the first resistor is greater than the resistance value of the second resistor, and the resistors in the different parallel measurement branches are different.

[0097] When the second measurement circuit comprises a fourth resistor and a fourth switch connected in series with each other; the fourth switch is connected to the total negative electrode of the battery pack, and the fourth resistor is connected to the first measurement circuit.

[0098] It should be noted that the first measurement branch and the second measurement branch are branches in parallel relationship, and the first measurement branch and the second measurement branch are not turned on at the same time, i.e. only the first measurement branch or the second measurement branch is turned on at the same time, by switching the switches in different measurement branches at different times, the measurement branches comprising different resistors are turned on at different times, so as to realize the difference in current value in different measurement branches.

[0099] Before the two probes of the first voltmeter are connected to the total positive electrode of the battery pack and the shell of the battery pack to obtain the second voltage value, and the two probes of the second voltmeter are connected to the total negative electrode of the battery pack and the shell of the battery pack to obtain the third voltage value, the following steps can be included, but are not limited to:

[0100] When the first switch and the fourth switch are turned on, and the second switch is turned off, so that the first measurement branch is turned on with the second measurement circuit, and the second measurement branch is turned off, the voltage value of the first resistor measured by the third voltmeter is the fourth voltage value, and the first current value flowing through the first resistor is obtained by calculation according to the obtained resistance value of the first resistor, wherein the fourth resistor can be used for current limiting or voltage dividing of the turned-on first measurement branch and the second measurement circuit; that is, the first current value of the first resistor is the ratio of the fourth voltage value to the resistance value of the first resistor.

[0101] When the second switch and the fourth switch are turned on, the first switch is turned off, the first measuring branch is disconnected, and the second measuring branch is connected to the second measuring circuit, the third voltmeter measures the voltage value of the second resistor as a fifth voltage value, and the second current value flowing through the second resistor is obtained according to the obtained resistance value of the second resistor; wherein the second current value is greater than or equal to the first current value, wherein the fourth resistor can also be used for current limiting or voltage dividing of the connected second measuring branch and second measuring circuit; that is, the second current value of the second resistor is the ratio of the fifth voltage value to the resistance value of the second resistor.

[0102] If the absolute value of the difference between the second current value and the first current value is less than or equal to the second preset value, the second current value is taken as the leakage current value of the battery cell in the battery pack.

[0103] If the leakage current value is greater than the third preset value, it is determined that the battery pack leaks electricity.

[0104] Preferably, the first measuring circuit comprises: a first measuring branch comprising a first resistor and a first switch, a second measuring branch comprising a second resistor and a second switch, and a third voltmeter, and can further comprise:

[0105] a third measuring branch and a fourth measuring branch; wherein

[0106] The third measuring branch can be a measuring branch comprising a fifth resistor and an eighth switch, and the fourth measuring branch can be a measuring branch comprising a sixth resistor and a ninth switch. Wherein the second resistor is less than or equal to the first resistor, the resistance value of the first resistor is less than or equal to the fifth resistor in the third measuring branch, and the resistance value of the first resistor is also less than or equal to the sixth resistor in the fourth measuring branch. That is, the resistors in different measuring branches are different.

[0107] The first measuring branch, the second measuring branch, the third measuring branch, and the fourth measuring branch belong to parallel branches, and the first measuring branch, the second measuring branch, the third measuring branch, and the fourth measuring branch are not connected at the same time. That is, at the same time, only one of the above measuring branches is connected. The first measuring branch, the second measuring branch, the third measuring branch, and the fourth measuring branch are connected in parallel.

[0108] Preferably, the first measuring circuit comprises: a first measuring branch, a second measuring branch, and a third voltmeter, and can further comprise: a fifth measuring branch, wherein the fifth measuring branch is a branch comprising a seventh switch, and the first measuring branch, the second measuring branch, and the fifth measuring branch are connected in parallel.

[0109] It should be noted that if the absolute value of the difference between the second current value and the first current value is less than or equal to the second preset value, when the second preset value is set to be infinitely close to 0, the second current value is infinitely close to the first current value.

[0110] In S103, if the absolute value of the difference between the half of the first voltage value and the second voltage value is greater than the first preset value, a ratio operation is performed on the second voltage value and the rated voltage value of the single cell in the battery pack to obtain a first ratio, and the position of the cell with leakage in the battery pack is determined according to the first ratio; or, if the absolute value of the difference between the half of the first voltage value and the third voltage value is greater than the first preset value, a ratio operation is performed on the third voltage value and the rated voltage value of the single cell in the battery pack to obtain a second ratio, and the position of the cell with leakage in the battery pack is determined according to the second ratio.

[0111] It should be noted that the first preset value in the embodiment of the application can be 0.1V, the first ratio can be a positive integer, and the second ratio can also be a positive integer. The sum of the first ratio and the second ratio is the number of cells in the battery pack. When the battery pack has N cells, the sum of the first ratio and the second ratio is N; wherein N is a positive integer.

[0112] Specifically, the N cells in the battery pack are connected in series in turn, the first cell connected to the total negative electrode of the battery pack is numbered 1, the second cell connected in series with the first cell in the battery pack is numbered 2, and the numbering of the N cells in the battery pack is completed in turn based on the series connection order of the cells, wherein the first cell connected to the total positive electrode of the battery pack is numbered N.

[0113] According to the first ratio, the position of the cell with leakage in the battery pack is determined, which can specifically include but is not limited to:

[0114] According to the first ratio, the first cell connected to the total positive electrode of the battery pack is determined as the starting point of counting, and based on the series connection order of the N cells in the battery pack, it is determined that the first ratio of cells leak, which can be because the negative electrode of the first ratio of cells leaks, so that the negative electrode of the first ratio of cells leaks, wherein the first ratio is less than or equal to N.

[0115] Preferably, the N cells in the battery pack are connected in series in turn, the first cell connected to the total negative electrode of the battery pack is numbered 1, the second cell connected in series with the first cell in the battery pack is numbered 2, and the numbering of the N cells in the battery pack is completed in turn based on the series connection order of the cells, wherein the first cell connected to the total positive electrode of the battery pack is numbered N.

[0116] According to the second ratio, the position of the cell with leakage in the battery pack is determined, which can specifically include:

[0117] The second ratio is increased by 1 to obtain a third ratio, based on the series order of the N cells in the battery pack, the third ratio of cells are determined to be leaked, and the negative electrode of the third ratio of cells can be leaked, wherein the third ratio is less than or equal to N.

[0118] For example, the battery pack includes 7 cells in series, wherein the rated voltage value of each cell is 3.2V.

[0119] If the total voltage of the battery pack is measured by the first and second voltmeters connected in series as 22.4V, that is, the first voltage value is 22.4V, then half of the first voltage value is 11.2V.

[0120] The second voltage value is obtained by connecting the total positive electrode of the battery pack and the shell of the battery pack through the two probes of the first voltmeter as 19.2V, and the third voltage value is obtained by connecting the total negative electrode of the battery pack and the shell of the battery pack through the two probes of the second voltmeter as 3.2V. Then the absolute value of the difference between 11.2V and 19.2V is 2V, and when the first preset value is 0.1V, the first ratio is determined by calculation. Specifically as follows:

[0121] By calculating 19.2V / 3.2V=6, the first ratio can be 6, and the first cell physically connected to the total positive electrode of the battery pack is determined as the counting starting point. The negative electrode of the 6th cell is leaked. By calculating 3.2V / 3.2V=1, the second ratio can be 1, and the third ratio is 2. Based on the series order of the 7 cells in the battery pack, it is determined that the negative electrode of the 2nd cell is leaked.

[0122] For example, the first voltmeter is V1, the second voltmeter is V2, the first switch is K1, the first resistor is R3, the second switch is K2, the second resistor is R4, the third switch is S1, the third resistor is R1, the third voltmeter is V3, the fourth switch is S2, the fourth resistor is R2, the fifth switch is S3, the sixth switch is S4, the seventh switch is K25, the fifth resistor is R5, the eighth switch is K3, the sixth resistor is R26, and the ninth switch is K24. For example, as shown in Figure 2 , Figure 2 It can be a system schematic diagram for executing the method for determining the position of the leaked cell in the battery pack. The system can include but is not limited to: V1, V2, V3, K1, K2, K3, K24, K25, R1, R2, R3, R4, R5, R26, battery pack and other devices. In this application, the method for determining the position of the leaked cell in the battery pack is executed by the devices in the system.

[0123] Specifically, the total voltage of the battery pack is measured as a first voltage value through V1 and V2 connected in series with each other; a second voltage value is obtained by connecting the total positive electrode of the battery pack and the shell of the battery pack through the two probes of V1, and a third voltage value is obtained by connecting the total negative electrode of the battery pack and the shell of the battery pack through the two probes of V2; if the absolute value of the difference between half of the first voltage value and the second voltage value is greater than a first preset value, a first ratio is obtained by performing a ratio operation on the second voltage value and the rated voltage value of a single cell in the battery pack, and the position of the cell with leakage in the battery pack is determined according to the first ratio; or, if the absolute value of the difference between half of the first voltage value and the third voltage value is greater than the first preset value, a second ratio is obtained by performing a ratio operation on the third voltage value and the rated voltage value of a single cell in the battery pack, and the position of the cell with leakage in the battery pack is determined according to the second ratio.

[0124] Preferably, the detection circuit for detecting the leakage of the battery pack can comprise: a first measurement circuit for detecting the leakage current value of the cell in the battery pack, and a second measurement circuit connected in series with the first side of the first measurement circuit, wherein the second side of the first measurement circuit is connected to the shell of the battery pack.

[0125] The first measurement branch comprises R3 and K1, and the second measurement branch comprises R4 and K2.

[0126] Therefore, the first measurement circuit can comprise but is not limited to: a first measurement branch comprising R3 and K1, a second measurement branch comprising R4 and K2, and V3; wherein V3 can be used to measure the voltage value of R3 in the first measurement branch and the voltage value of R4 in the second measurement branch, respectively; the first measurement branch and the second measurement branch are connected in parallel,

[0127] When the second measurement circuit can be R1 and S1 connected in series with each other; S1 is connected to the total positive electrode of the battery pack, and R1 is connected to the first measurement circuit.

[0128] Before the second voltage value is obtained by connecting the total positive electrode of the battery pack and the shell of the battery pack through the two probes of V1, and the third voltage value is obtained by connecting the total negative electrode of the battery pack and the shell of the battery pack through the two probes of V2, the following steps can be included but are not limited to:

[0129] When K1 and S1 are turned on and K2 is turned off, so that the first measurement branch and the second measurement circuit are turned on, and the second measurement branch is turned off, the voltage value of R3 is measured as a fourth voltage value through V3, and the first current value flowing through R3 is obtained by calculation according to the obtained resistance value of R3, wherein R1 is used to limit the current of the turned-on first measurement branch and second measurement circuit; the first current value flowing through R3 is the ratio of the fourth voltage value to the resistance value of R3.

[0130] When K2 and S1 are connected and K1 is disconnected, the first measurement branch is disconnected and the second measurement branch is connected to the second measurement circuit. The voltage value of R4 is measured by V3 to be the fifth voltage value. Based on the obtained resistance value of R4, the second current value of R4 is obtained. The second current value is greater than or equal to the first current value. R1 is also used to limit the current of the connected second measurement branch and the second measurement circuit.

[0131] If the absolute value of the difference between the second current value and the first current value is less than or equal to the second preset value, then the second current value will be used as the leakage current value of the cell in the battery pack.

[0132] Determine whether the leakage current value is less than or equal to a third preset value. If the leakage current value is greater than the third preset value, then the battery pack is determined to be leaking current.

[0133] Preferably, the first measurement circuit may include, in addition to a first measurement branch including R3 and K1, and a second measurement branch including R4 and K2, also including but not limited to:

[0134] The third and fourth measurement branches; among them...

[0135] The third measurement branch can be a measurement branch including R5 and K3, and the fourth measurement branch can be a measurement branch including R26 and K24.

[0136] Preferably, the first measuring circuit includes, in addition to the first measuring branch, the second measuring branch, and the third voltmeter, a fifth measuring branch, wherein the fifth measuring branch may be a measuring branch including K25; that is, using the fifth measuring branch, the two probes of the first voltmeter can be connected to the positive terminal of the battery pack and the casing of the battery pack respectively to obtain a second voltage value; using the fifth measuring branch, the two probes of the second voltmeter can be connected to the negative terminal of the battery pack and the casing of the battery pack respectively to obtain a third voltage value.

[0137] Preferably, the two probes of V1 include a first probe and a second probe; the two probes of V2 include a third probe and a fourth probe.

[0138] The total voltage of the battery pack is measured using V1 and V2 connected in series as the first voltage value, which may specifically include:

[0139] By connecting the first probe of V1 to the positive terminal of the battery pack, connecting the second probe of V1 to the third probe of V2, and connecting the fourth probe of V2 to the negative terminal of the battery pack, V1 and V2 are connected in series, and the total voltage of the battery pack is measured to obtain the first voltage value. Among them, after the second probe and the third probe are connected, they can be connected to the battery pack casing based on K25 in the fifth measurement branch.

[0140] Preferably, the first probe of V1 is connected between the total positive poles of the battery pack with S3, and the fourth probe of the second voltmeter is connected between the total negative poles of the battery pack with S4;

[0141] When the first measuring circuit and the second measuring circuit are provided with switches, the total voltage of the battery pack measured by the V1 and the V2 voltmeters connected in series is the first voltage value, which can specifically include:

[0142] The first probe of V1 is connected to the conducting S3, the total positive poles of the battery pack are connected through the conducting S3, the second probe of V1 is connected to the third probe of the second voltmeter, and the fourth probe of V2 is connected to the conducting S4, the total negative poles of the battery pack are connected through the conducting S4, so as to realize the series connection of V1 and V2, and measure the total voltage of the battery pack to obtain the first voltage value of the total voltage of the battery pack.

[0143] Preferably, the first probe of V1 is connected between the total positive poles of the battery pack with S3, and the fourth probe of V2 is connected between the total negative poles of the battery pack with S4, the second probe of V1 is connected between the shells of the battery pack with K25, and the third probe of V2 is also connected between the shells of the battery pack with K25;

[0144] The two probes of V1 are connected to the total positive poles of the battery pack and the shells of the battery pack respectively to obtain the second voltage value, and at the same time, the two probes of V2 are connected to the total negative poles of the battery pack and the shells of the battery pack respectively to obtain the third voltage value, which can specifically include but not limited to:

[0145] The first probe of V1 is connected to the conducting S3, and the total positive poles of the battery pack are connected through the conducting S3, the second probe of V1 is connected to the conducting K25, and the shells of the battery pack are connected through the conducting K25 to obtain the second voltage value, at the same time, the third probe of V2 is connected to the conducting K25, the shells of the battery pack are connected through the conducting K25, and the fourth probe of V2 is connected to the conducting S4, the total negative poles of the battery pack are connected through the conducting S4 to obtain the third voltage value.

[0146] Figure 3 Another example shows the structure of the position determination device for the electric core of the battery pack, as shown in Figure 3 As shown in the figure, the position determination device 30 can include but not limited to: a measurement module 301, an operation module 302 and a determination module 303; wherein,

[0147] The measurement module 301 can be used to measure the total voltage of the battery pack by the first voltmeter and the second voltmeter connected in series;

[0148] The measuring module 301 is further configured to: connect the total positive pole of the battery pack and the shell of the battery pack by two probes of a first voltmeter to obtain a second voltage value, and connect the total negative pole of the battery pack and the shell of the battery pack by two probes of a second voltmeter to obtain a third voltage value;

[0149] The calculating module 302 is configured to: if an absolute value of a difference between half of the first voltage value and the second voltage value is greater than a first preset value, perform a ratio operation on the second voltage value and a rated voltage value of a single cell in the battery pack to obtain a first ratio value;

[0150] The determining module 303 is configured to: determine a position of a cell leaking current in the battery pack according to the first ratio value;

[0151] The calculating module 302 is further configured to: if an absolute value of a difference between half of the first voltage value and the third voltage value is greater than the first preset value, perform a ratio operation on the third voltage value and the rated voltage value of the single cell in the battery pack to obtain a second ratio value;

[0152] The determining module 303 is further configured to: determine the position of the cell leaking current in the battery pack according to the second ratio value.

[0153] Preferably, the determining module 303 is specifically configured to:

[0154] when N cells in the battery pack are connected in series, a first cell physically connected to the total negative pole of the battery pack is numbered 1, a second cell connected in series with the first cell in the battery pack is numbered 2, and the numbering of the N cells in the battery pack is sequentially completed based on the series connection order of the cells,

[0155] based on the first ratio value, the first cell physically connected to the total positive pole of the battery pack is determined as a counting starting point, and first ratio value cells are determined to leak current based on the series connection order of the N cells in the battery pack, wherein the first cell physically connected to the total positive pole of the battery pack is numbered N, and the first ratio value is less than or equal to N;

[0156] Preferably, the determining module 303 is specifically configured to:

[0157] when N cells in the battery pack are connected in series, a first cell physically connected to the total negative pole of the battery pack is numbered 1, a second cell connected in series with the first cell in the battery pack is numbered 2, and the numbering of the N cells in the battery pack is sequentially completed based on the series connection order of the cells,

[0158] the second ratio value is increased by 1 to obtain a third ratio value, and based on the series connection order of the N cells in the battery pack, third ratio value cells are determined to leak current, that is, the negative poles of the third ratio value cells are determined to leak current, wherein the third ratio value is less than or equal to N.

[0159] Preferably, the measuring module 301 can be used specifically for:

[0160] When the two probes of the first voltmeter include: a first probe, a second probe, and the two probes of the second voltmeter include: a third probe, a fourth probe,

[0161] By connecting the first probe of the first voltmeter to the total positive pole of the battery pack, connecting the second probe of the first voltmeter to the third probe of the second voltmeter, and connecting the fourth probe of the second voltmeter to the total negative pole of the battery pack, the first voltmeter and the second voltmeter are connected in series, and the total voltage of the battery pack is measured, obtaining the total voltage of the battery pack as the first voltage value; wherein the second probe and the third probe are connected together and connected to the shell of the battery pack.

[0162] Preferably, the measuring module 301 can be used specifically for:

[0163] When the first probe of the first voltmeter is connected between the total positive pole of the battery pack and the fifth switch, and the fourth probe of the second voltmeter is connected between the total negative pole of the battery pack and the sixth switch,

[0164] Connect the first probe of the first voltmeter to the fifth switch, connect the total positive pole of the battery pack through the fifth switch, connect the second probe of the first voltmeter to the third probe of the second voltmeter, and connect the fourth probe of the second voltmeter to the sixth switch. Connect the total negative pole of the battery pack through the sixth switch to realize the series connection of the first voltmeter and the second voltmeter, and measure the total voltage of the battery pack, obtaining the total voltage of the battery pack as the first voltage value.

[0165] Preferably, the measuring module 301 can be used specifically for:

[0166] When the first probe of the first voltmeter is connected between the total positive pole of the battery pack and the fifth switch, and the fourth probe of the second voltmeter is connected between the total negative pole of the battery pack and the sixth switch, the second probe of the first voltmeter is connected between the shell of the battery pack and the seventh switch, and the third probe of the second voltmeter is also connected between the shell of the battery pack and the seventh switch,

[0167] Connect the first probe of the first voltmeter to the fifth switch, and connect the total positive pole of the battery pack through the fifth switch, connect the second probe of the first voltmeter to the seventh switch, and connect the shell of the battery pack through the seventh switch, obtain the second voltage value after measurement, and at the same time, connect the third probe of the second voltmeter to the seventh switch, connect the shell of the battery pack through the seventh switch, and connect the fourth probe of the second voltmeter to the sixth switch. Connect the total negative pole of the battery pack through the sixth switch to obtain the third voltage value after measurement.

[0168] Preferably, the position determining device 30 can comprise, but not limited to, a measuring module 301, a calculating module 302 and a determining module 303, and can further comprise, but not limited to:

[0169] a detecting circuit for detecting the leakage current of the battery pack and a determining module; wherein,

[0170] the detecting circuit for detecting the leakage current of the battery pack comprises a first measuring circuit for detecting the leakage current of the battery pack, and a second measuring circuit connected in series with the first side of the first measuring circuit, wherein the second side of the first measuring circuit is connected to the shell of the battery pack; wherein,

[0171] the first measuring circuit comprises a first measuring branch, a second measuring branch and a third voltmeter, wherein,

[0172] the first measuring branch comprises a first resistor and a first switch, and the second measuring branch comprises a second resistor and a second switch; the first measuring branch and the second measuring branch are connected in parallel, and the third voltmeter is used for measuring the voltage value of the first resistor in the first measuring branch and the voltage value of the second resistor in the second measuring branch, respectively, wherein the resistance value of the first resistor is greater than the resistance value of the second resistor;

[0173] when the second measuring circuit comprises a third resistor and a third switch connected in series with each other, the second measuring circuit is connected to the total positive electrode of the battery pack through the third switch and connected to the first measuring circuit through the third resistor;

[0174] the calculating module 302 can be further used for:

[0175] when the first switch and the third switch are turned on and the second switch is turned off, so that the first measuring branch is turned on and the second measuring branch is turned off, the voltage value of the first resistor measured by the third voltmeter is a fourth voltage value, and the first current value of the first resistor is obtained by calculation according to the obtained resistance value of the first resistor, wherein the third resistor is used for current limiting of the turned-on first measuring branch and the second measuring circuit; and

[0176] when the second switch and the third switch are turned on and the first switch is turned off, so that the first measuring branch is turned off and the second measuring branch is turned on, the voltage value of the second resistor measured by the third voltmeter is a fifth voltage value, and the second current value of the second resistor is obtained according to the obtained resistance value of the second resistor, wherein the second current value is greater than or equal to the first current value, and the third resistor is further used for current limiting of the turned-on second measuring branch and the second measuring circuit;

[0177] the determining module can be used for:

[0178] If an absolute value of a difference between the second current value and the first current value is less than or equal to a second preset value, the second current value is taken as the leakage current value of the battery cell in the battery pack.

[0179] If the leakage current value is greater than a third preset value, it is determined that the battery pack leaks electricity.

[0180] Preferably, when the second measuring circuit comprises a fourth resistor and a fourth switch connected in series, the fourth switch is connected to a total negative electrode of the battery pack, and the fourth resistor is connected to the first measuring circuit,

[0181] The operation module 302 can also be configured to:

[0182] When the first switch and the fourth switch are turned on and the second switch is turned off, the first measuring branch and the second measuring circuit are turned on, and the second measuring branch is turned off, the fourth resistor is used to limit the current of the turned-on first measuring branch and the second measuring circuit, the third voltmeter is used to measure a fourth voltage value of the first resistor, and the first current value of the first resistor is obtained by calculation according to the obtained resistance value of the first resistor.

[0183] When the second switch and the fourth switch are turned on and the first switch is turned off, the first measuring branch is turned off, the second measuring branch and the second measuring circuit are turned on, the third resistor is used to limit the current of the turned-on second measuring branch and the second measuring circuit, the third voltmeter is used to measure a fifth voltage value of the second resistor, and the second current value of the second resistor is obtained according to the obtained resistance value of the second resistor.

[0184] The judgment module can also be configured to:

[0185] If an absolute value of a difference between the second current value and the first current value is less than or equal to a second preset value, the second current value is taken as the leakage current value of the battery cell in the battery pack.

[0186] If the leakage current value is greater than a third preset value, it is determined that the battery pack leaks electricity.

[0187] The application provides a position determination device of a battery cell leaking electricity in a battery pack, Figure 4 is a structural schematic diagram of the determination device provided by the application. In the embodiment of the application, Figure 4 The position determination device in the embodiment of the application can be configured to execute the position determination method of the battery cell leaking electricity in the battery pack in the method in the embodiment of the application. Figure 1

[0188] As shown in Figure 4 ​As shown, the location determination device 40 may include, but is not limited to, a processor 41 and a memory 42;

[0189] It should be noted that memory 42 is coupled to processor 41, and memory 42 can be used to store... Figure 1 The application code for determining the location of the leaking battery cell in the battery pack in the embodiment is configured by processor 41 to call... Figure 1 The application code for determining the location of leaking cells in the battery pack in the embodiment is used for execution. Figure 1 The embodiment describes a method for determining the location of a leaking battery cell in the battery pack. Specifically,

[0190] Processor 41 can be used for:

[0191] The total voltage of the battery pack is measured by a first voltmeter and a second voltmeter connected in series, and this is the first voltage value.

[0192] A second voltage value is obtained by connecting the two probes of the first voltmeter to the positive terminal of the battery pack and the battery pack casing, respectively; and a third voltage value is obtained by connecting the two probes of the second voltmeter to the negative terminal of the battery pack and the battery pack casing, respectively.

[0193] If the absolute value of the difference between half of the first voltage value and the second voltage value is greater than a first preset value, then the second voltage value is compared with the rated voltage value of a single cell in the battery pack to obtain a first ratio. Based on this first ratio, the location of the leaking cell in the battery pack is determined; or...

[0194] If the absolute value of the difference between half of the first voltage value and the third voltage value is greater than the first preset value, then the third voltage value is compared with the rated voltage value of a single cell in the battery pack to obtain a second ratio. The location of the leaking cell in the battery pack is determined based on the second ratio. More specifically, when the battery pack includes N cells, the second ratio is increased by 1 to obtain a third ratio. Taking the first cell physically connected to the total negative terminal of the battery pack as the counting starting point, the number of leaking cells in the third ratio is determined based on the series sequence of the N cells in the battery pack, where the third ratio is less than or equal to N.

[0195] Understandable, regarding Figure 4 For the specific implementation of the location determination device 40, please refer to [reference needed]. Figures 1-3 The specific implementation examples are not described here.

[0196] It should be understood that the location determination device 40 is only one example provided in the embodiments of this application, and the location determination device 40 may have more or fewer components than those shown, may combine two or more components, or may be implemented with different configurations of components.

[0197] It should be noted that,Figures 1-4 The various embodiments described can be combined with each other.

[0198] Figures 1-4 The above merely serves as an example for describing the embodiments of the present application, and should not be used to limit the protection scope of the present application.

[0199] Those skilled in the art can clearly understand that the devices, apparatuses and method steps of the examples described in combination with the embodiments disclosed in the present application can be realized by electronic hardware, computer software or a combination of both. In order to clearly illustrate the interchangeability of hardware and software, the components and steps of the examples have been described in general terms in the above description. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0200] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described apparatus and device can refer to the corresponding process in the foregoing method embodiments, which will not be repeated here.

[0201] In several embodiments provided in the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the components and steps of the examples are described. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0202] The above-described embodiments of the system and device are merely illustrative, and in addition, the coupling or direct coupling or communication connection between the displayed or discussed each other can be indirect coupling or communication connection through some interfaces, devices, apparatuses, circuits or modules, and can also be electrical, mechanical or other form of connection.

[0203] Based on such understanding, the technical scheme of the present application, essentially or in other words, the part of the prior art that contributes to the present application, or the whole or part of the technical scheme can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in various embodiments of the present application. The aforementioned storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0204] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for determining the location of a leaking cell in a battery pack, characterized in that, The total voltage of the battery pack is measured by a first voltmeter and a second voltmeter connected in series, and this is the first voltage value. A second voltage value is obtained by connecting the two probes of the first voltmeter to the positive terminal of the battery pack and the battery pack casing, respectively; and a third voltage value is obtained by connecting the two probes of the second voltmeter to the negative terminal of the battery pack and the battery pack casing, respectively. If the absolute value of the difference between half of the first voltage value and the second voltage value is greater than a first preset value, then the second voltage value is compared with the rated voltage value of a single cell in the battery pack to obtain a first ratio. Based on this first ratio, the location of the leaking cell in the battery pack is determined; or... If the absolute value of the difference between half of the first voltage value and the third voltage value is greater than the first preset value, then the third voltage value is compared with the rated voltage value of a single cell in the battery pack to obtain a second ratio, and the location of the leaking cell in the battery pack is determined based on the second ratio. The detection circuit for detecting leakage current in the battery pack includes: a first measuring circuit for detecting the leakage current value of the cells in the battery pack, and a second measuring circuit connected in series with a first side of the first measuring circuit, wherein the second side of the first measuring circuit is connected to the casing of the battery pack; wherein... The first measurement circuit includes: a first measurement branch, a second measurement branch, and a third voltmeter, wherein, The first measurement branch includes: a first resistor and a first switch; the second measurement branch includes: a second resistor and a second switch. The second measurement circuit includes: a third resistor and a third switch connected in series; the third switch is connected to the positive terminal of the battery pack, and the third resistor is connected to the first measurement circuit. Before obtaining a second voltage value by connecting the two probes of the first voltmeter to the positive terminal of the battery pack and the battery pack casing respectively, and simultaneously obtaining a third voltage value by connecting the two probes of the second voltmeter to the negative terminal of the battery pack and the battery pack casing respectively, the position determination method further includes: When the first switch and the third switch are turned on and the second switch is turned off, the first measuring branch is connected to the second measuring circuit. When the second measuring branch is turned off, the voltage value of the first resistor is measured by the third voltmeter and the fourth voltage value is obtained. Based on the obtained resistance value of the first resistor, the first current value of the first resistor is calculated. The third resistor is used to limit the current of the connected first measuring branch and the second measuring circuit. When the second and third switches are turned on and the first switch is turned off, the first measuring branch is disconnected and the second measuring branch is connected to the second measuring circuit. The voltage value of the second resistor is measured by the third voltmeter as the fifth voltage value. Based on the obtained resistance value of the second resistor, the second current value of the second resistor is obtained. The second current value is greater than the first current value. The third resistor is also used to limit the current in the connected second measuring branch and the second measuring circuit. If the absolute value of the difference between the second current value and the first current value is less than or equal to the second preset value, then the second current value will be used as the leakage current value of the cell in the battery pack. Determine whether the leakage current value is less than or equal to a third preset value. If the leakage current value is greater than the third preset value, then the battery pack is determined to be leaking current. The first measurement circuit also includes: The third and fourth measurement branches; among them... The third measurement branch can be a measurement branch including the fifth resistor and the eighth switch; the fourth measurement branch can be a measurement branch including the sixth resistor and the ninth switch; the resistors in different measurement branches are different; The first measurement branch, the second measurement branch, the third measurement branch, and the fourth measurement branch are parallel branches, and the first measurement branch, the second measurement branch, the third measurement branch, and the fourth measurement branch are not simultaneously turned on. That is, at any given time, only one of the above multiple measurement branches is turned on; the first measurement branch, the second measurement branch, the third measurement branch, and the fourth measurement branch are connected in parallel. The first measurement circuit further includes a fifth measurement branch, wherein the fifth measurement branch includes a seventh switch. The fifth measurement branch is used to connect the two probes of the first voltmeter to the positive terminal of the battery pack and the casing of the battery pack respectively to obtain a second voltage value; and the fifth measurement branch is used to connect the two probes of the second voltmeter to the negative terminal of the battery pack and the casing of the battery pack respectively to obtain a third voltage value.

2. The method for determining the location of a leaking cell in a battery pack as described in claim 1, characterized in that, The battery pack has N cells connected in series. The first cell physically connected to the negative electrode of the battery pack is numbered 1, and the second cell connected in series with the first cell is numbered 2. Based on the series connection order of the cells, the N cells in the battery pack are numbered sequentially, where the first cell physically connected to the positive electrode of the battery pack is numbered N. The location of the leaking battery cell in the battery pack is determined based on the first ratio, specifically including: Based on the first ratio, the first cell physically connected to the total positive electrode of the battery pack is determined as the counting starting point. Based on the series sequence of N cells in the battery pack, the leakage of the first ratio of cells is determined, wherein the first ratio is less than or equal to N.

3. The method for determining the location of a leaking cell in a battery pack as described in claim 1, characterized in that, The battery pack has N cells connected in series. The first cell physically connected to the negative electrode of the battery pack is numbered 1, and the second cell connected in series with the first cell is numbered 2. Based on the series connection order of the cells, the N cells in the battery pack are numbered sequentially, where the first cell physically connected to the positive electrode of the battery pack is numbered N. The location of the leaking battery cell in the battery pack is determined based on the second ratio, specifically including: The second ratio is increased by 1 to obtain the third ratio. Taking the first cell physically connected to the total negative terminal of the battery pack as the counting starting point, the leakage of the third ratio cell is determined based on the series sequence of the N cells in the battery pack, where the third ratio is less than or equal to N.

4. The method for determining the location of a leaking cell in a battery pack as described in claim 1, characterized in that, The first measurement branch and the second measurement branch are connected in parallel. The third voltmeter is used to measure the voltage value of the first resistor in the first measurement branch and the voltage value of the second resistor in the second measurement branch, wherein the resistance value of the first resistor is greater than the resistance value of the second resistor.

5. The method for determining the location of a leaking cell in a battery pack as described in claim 1, characterized in that, The first voltmeter has two probes: a first probe and a second probe; the second voltmeter has two probes: a third probe and a fourth probe. The total voltage of the battery pack is measured using a first voltmeter and a second voltmeter connected in series, which is the first voltage value. Specifically, this includes: By connecting the first probe of the first voltmeter to the positive terminal of the battery pack, connecting the second probe of the first voltmeter to the third probe of the second voltmeter, and connecting the fourth probe of the second voltmeter to the negative terminal of the battery pack, the first voltmeter and the second voltmeter are connected in series to measure the total voltage of the battery pack and obtain the total voltage of the battery pack as the first voltage value; wherein, after the second probe and the third probe are connected, they are connected to the casing of the battery pack.

6. The method for determining the location of a leaking cell in a battery pack as described in claim 5, characterized in that, A fifth switch is provided between the first probe of the first voltmeter and the total positive terminal of the battery pack, and a sixth switch is provided between the fourth probe of the second voltmeter and the total negative terminal of the battery pack. The total voltage of the battery pack is measured using a first voltmeter and a second voltmeter connected in series, which is the first voltage value. Specifically, this includes: Connect the first probe of the first voltmeter to the fifth switch, which is on, and then connect the fifth switch to the positive terminal of the battery pack. Connect the second probe of the first voltmeter to the third probe of the second voltmeter, and connect the fourth probe of the second voltmeter to the sixth switch, which is on, and then connect the sixth switch to the negative terminal of the battery pack. This allows the first and second voltmeters to be connected in series, and the total voltage of the battery pack is measured to obtain the first voltage value.

7. The method for determining the location of a leaking cell in a battery pack as described in claim 1, characterized in that, The first voltmeter has two probes: a first probe and a second probe; the second voltmeter has two probes: a third probe and a fourth probe. A fifth switch is provided between the first probe of the first voltmeter and the positive terminal of the battery pack; a sixth switch is provided between the fourth probe of the second voltmeter and the negative terminal of the battery pack; a seventh switch is provided between the second probe of the first voltmeter and the outer casing of the battery pack; and the seventh switch is also provided between the third probe of the second voltmeter and the outer casing of the battery pack. A second voltage value is obtained by connecting the two probes of the first voltmeter to the positive terminal of the battery pack and the battery pack casing, respectively. Simultaneously, a third voltage value is obtained by connecting the two probes of the second voltmeter to the negative terminal of the battery pack and the battery pack casing, respectively. Specifically, this includes: A second voltage value is obtained by connecting the first probe of the first voltmeter to the fifth switch, which is in operation, and then connecting the fifth switch to the positive terminal of the battery pack. A second voltage value is obtained by connecting the second probe of the first voltmeter to the seventh switch, which is in operation, and then connecting the seventh switch to the battery pack casing. A third voltage value is obtained by connecting the third probe of the second voltmeter to the seventh switch, which is in operation, and then connecting the fourth probe of the second voltmeter to the sixth switch, which is in operation, and then connecting the sixth switch to the negative terminal of the battery pack.

8. A device for determining the location of a leaking battery cell in a battery pack, characterized in that, include: The module consists of a measurement module, a calculation module, and a determination module; among which, The measurement module is used to measure the total voltage of the battery pack as a first voltage value using a first voltmeter and a second voltmeter connected in series. The measurement module is also used to: obtain a second voltage value by connecting the two probes of the first voltmeter to the positive terminal of the battery pack and the casing of the battery pack respectively, and to obtain a third voltage value by connecting the two probes of the second voltmeter to the negative terminal of the battery pack and the casing of the battery pack respectively. The calculation module is used to: if the absolute value of the difference between half of the first voltage value and the second voltage value is greater than the first preset value, then perform a ratio calculation between the second voltage value and the rated voltage value of a single cell in the battery pack to obtain the first ratio; The determining module is used to: determine the location of the leaking battery cell in the battery pack based on the first ratio; The calculation module is also used to: if the absolute value of the difference between half of the first voltage value and the third voltage value is greater than the first preset value, then perform a ratio calculation between the third voltage value and the rated voltage value of a single cell in the battery pack to obtain a second ratio; The determining module is also used to: determine the location of the leaking cell in the battery pack based on the second ratio; The location determination device further includes: a detection circuit for detecting battery pack leakage and a judgment module; wherein, The detection circuit for detecting battery pack leakage includes: a first measuring circuit for detecting the leakage current value of the cells in the battery pack; and a second measuring circuit connected in series with a first side of the first measuring circuit, wherein the second side of the first measuring circuit is connected to the casing of the battery pack; wherein... The first measurement circuit includes: a first measurement branch, a second measurement branch, and a third voltmeter, wherein, The first measurement branch includes: a first resistor and a first switch; the second measurement branch includes: a second resistor and a second switch. The second measurement circuit includes a third resistor and a third switch connected in series; the second measurement circuit is connected to the positive terminal of the battery pack through the third switch and to the first measurement circuit through the third resistor. The computing module is also used for: When the first and third switches are turned on and the second switch is turned off, the first measuring branch is connected to the second measuring circuit. When the second measuring branch is disconnected, the voltage value of the first resistor is measured by the third voltmeter as the fourth voltage value. Based on the obtained resistance value of the first resistor, the first current value of the first resistor is calculated. The third resistor is used to limit the current in the connected first measuring branch and the second measuring circuit. When the second and third switches are turned on and the first switch is turned off, the first measuring branch is disconnected and the second measuring branch is connected to the second measuring circuit. The voltage value of the second resistor is measured by the third voltmeter as the fifth voltage value. Based on the obtained resistance value of the second resistor, the second current value of the second resistor is obtained. The second current value is greater than the first current value. The third resistor is also used to limit the current in the connected second measuring branch and the second measuring circuit. The judgment module is used for: If the absolute value of the difference between the second current value and the first current value is less than or equal to the second preset value, then the second current value will be used as the leakage current value of the cell in the battery pack. Determine whether the leakage current value is less than or equal to a third preset value. If the leakage current value is greater than the third preset value, then the battery pack is determined to be leaking current. The first measurement circuit also includes: The third and fourth measurement branches; among them... The third measurement branch can be a measurement branch including the fifth resistor and the eighth switch; the fourth measurement branch can be a measurement branch including the sixth resistor and the ninth switch; the resistors in different measurement branches are different; The first measurement branch, the second measurement branch, the third measurement branch, and the fourth measurement branch are parallel branches, and the first measurement branch, the second measurement branch, the third measurement branch, and the fourth measurement branch are not simultaneously turned on. That is, at any given time, only one of the above multiple measurement branches is turned on; the first measurement branch, the second measurement branch, the third measurement branch, and the fourth measurement branch are connected in parallel. The first measurement circuit further includes a fifth measurement branch, wherein the fifth measurement branch includes a seventh switch. The fifth measurement branch is used to connect the two probes of the first voltmeter to the positive terminal of the battery pack and the casing of the battery pack respectively to obtain a second voltage value; and the fifth measurement branch is used to connect the two probes of the second voltmeter to the negative terminal of the battery pack and the casing of the battery pack respectively to obtain a third voltage value.

9. The device for determining the location of a leaking cell in a battery pack as described in claim 8, characterized in that, The first measurement branch and the second measurement branch are connected in parallel. The third voltmeter is used to measure the voltage value of the first resistor in the first measurement branch and the voltage value of the second resistor in the second measurement branch, wherein the resistance value of the first resistor is greater than the resistance value of the second resistor.

10. A device for determining the location of a leaking cell in a battery pack, characterized in that, A memory and a processor connected to the memory, the memory being used to store application code, the processor being configured to call the application code to execute the method for determining the location of a leaking cell in a battery pack as described in any one of claims 1 to 7.

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