Test method, device, equipment and storage medium for internal resistance of copper busbar inside battery

Abstract

The present invention belongs to the technical field of lithium batteries, and discloses a test method, device, equipment and storage medium for the internal resistance of a copper bar inside a battery. The test method includes: collecting the voltage of a battery pack, judging whether the jumper copper bar in the battery pack has an influence on the voltage of the battery pack; if so, controlling the voltage value of the battery pack to change under preset conditions, wherein, in the battery pack, the voltage value of the battery cell connected to the jumper copper bar can change with the change of the preset conditions and the resistance value of the jumper copper bar; when the voltage value of the battery pack stops changing, obtaining the highest voltage and the lowest voltage of the battery cell in the battery pack; and determining the compensation resistance value of the jumper copper bar according to the highest voltage, the lowest voltage and the preset conditions. The present invention solves the problems existing in the method for measuring the internal resistance of the jumper copper bar in the prior art.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium batteries, and in particular relates to a method, device, equipment and storage medium for testing the internal resistance of a copper busbar inside a battery. Background Art

[0002] Lithium iron phosphate battery is a lithium-ion battery that uses lithium iron phosphate as the positive electrode material and carbon as the negative electrode material. Lithium iron phosphate battery has the advantages of high operating voltage, high energy density, long cycle life, good safety performance, low self-discharge rate and no memory effect. Lithium iron phosphate battery is widely used in forklifts and other equipment due to its good safety and low cost.

[0003] At present, there are two main methods for collecting and compensating the voltage of the copper bar across the battery pack. One is to use the equipment, charger, and load to charge / discharge the battery pack at a constant current, and then use a multimeter or other voltage measuring instrument to measure the voltage across the copper bar. The resistance of the copper bar is calculated by the formula R=U / I (i.e., the voltage across the copper bar divided by the charge / discharge current), and then written into the battery software (battery management system) for compensation; the other is to directly measure the resistance of the copper bar across the copper bar with a DC impedance tester, and then write it into the battery software (battery management system) for compensation;

[0004] Since the voltage acquisition process of the battery management system of the battery pack is mainly fixed by bolts or welding, and the measurement is mainly done by needle contact or test clip contact, and the measurement position has a great influence on the result, when the battery pack structure is precisely arranged or the structure is complex, accurate measurement cannot be performed, which easily leads to compensation deviation after the actual measurement result is written into the battery management system. At the same time, the above two battery pack jumper copper busbar voltage acquisition and compensation methods both require manual measurement. When the battery pack is assembled, it is impossible to measure. It can only be measured before the battery pack is assembled or after the battery pack cover is removed. In addition, when the battery pack structure is complex, there will be insufficient space for copper busbar measurement, which may easily lead to factors such as inability to measure or poor measurement position affecting the accuracy of the measurement results.

[0005] In summary, a method for measuring the internal resistance of a copper busbar connected across a battery is urgently needed in the relevant field, so that the method can overcome the problems existing in the method for measuring the internal resistance of a copper busbar connected across a battery in the above-mentioned prior art. Summary of the invention

[0006] The present invention provides a method, device, equipment and storage medium for testing the internal resistance of a copper busbar inside a battery, which are used to solve the problems existing in the method for measuring the internal resistance of a cross-connected copper busbar in the prior art.

[0007] In order to solve the above technical problems, in a first aspect, the present invention provides a method for testing the internal resistance of a copper busbar inside a battery, comprising:

[0008] Collecting the voltage of the battery pack, and determining whether the jumper copper busbar in the battery pack has an impact on the voltage of the battery pack;

[0009] If yes, the voltage value of the battery pack is controlled to change under a preset condition, wherein, in the battery pack, the voltage value of the battery cell connected to the jumper copper bar can change with the change of the preset condition and the resistance value of the jumper copper bar;

[0010] When the voltage value of the battery pack stops changing, obtaining the highest voltage and the lowest voltage of the battery cells in the battery pack;

[0011] The compensation resistance of the jumper copper bus is determined according to the highest voltage, the lowest voltage and the preset condition.

[0012] Optionally, collecting the voltage of the battery pack and determining whether the jumper copper bus in the battery pack has an impact on the voltage of the battery pack includes:

[0013] The battery pack is charged and discharged to determine whether the voltage change of the battery cells in the battery pack exceeds a normal level. If so, it is determined that the jumper copper busbar in the battery pack has an impact on the voltage of the battery pack.

[0014] Optionally, charging and discharging the battery pack to determine whether a voltage change of a cell in the battery pack exceeds a normal level includes:

[0015] Charging the battery pack, and observing the position of the highest voltage cell at the charging terminal of the battery pack when charging;

[0016] Discharging the battery pack, and observing the lowest voltage cell position where the lowest voltage at the end of discharge of the battery pack is located during discharge;

[0017] It is determined whether the highest voltage cell position is the same as the lowest voltage cell position, and if so, it is determined that the voltage change during charging and discharging in the battery pack exceeds a normal level.

[0018] Optionally, if yes, controlling the voltage value of the battery pack to change under a preset condition includes:

[0019] If yes, a preset constant current value is used to discharge the battery pack, and the voltage value of the battery pack is controlled to change with the discharge time.

[0020] Optionally, determining the compensation resistance of the jumper copper bus according to the highest voltage, the lowest voltage and the preset condition includes:

[0021] Recording a first voltage difference between a highest voltage and a lowest voltage of cells in the battery pack when the battery pack is discharged using a first constant current value;

[0022] recording a second voltage difference between a highest voltage and a lowest voltage of cells in the battery pack when the battery pack is discharged using a second constant current value, wherein the first constant current value is greater than the second constant current value;

[0023] Calculating a constant current difference between the first constant current value and the second constant current value, and a voltage difference between the first voltage difference and the second voltage difference;

[0024] The quotient of the voltage difference and the constant current difference is calculated to obtain the compensation resistance of the jumper copper busbar.

[0025] Optionally, discharging the battery pack and observing the position of the lowest voltage cell at the lowest discharge end voltage when the battery pack is discharged includes:

[0026] The battery pack is discharged at a constant current using a preset multiple of the rated current until the battery system triggers a protection mechanism, and the position of the lowest voltage cell at the lowest discharge end voltage of the battery pack during discharge is observed.

[0027] Optionally, after charging the battery pack and observing the highest voltage cell position where the highest voltage at the charging terminal of the battery pack is located during charging, and before discharging the battery pack and observing the lowest voltage cell position where the lowest voltage at the discharge terminal of the battery pack is located during discharging, the method further includes:

[0028] The battery pack is left to stand for a preset time until the battery pack is in a stable state.

[0029] In a second aspect, the present invention provides a device for testing the internal resistance of a copper busbar in a battery, comprising:

[0030] A judgment module, used for collecting the voltage of the battery pack and judging whether the jumper copper bar in the battery pack has an impact on the voltage of the battery pack;

[0031] A control module, if used to control the voltage value of the battery pack to change under preset conditions, wherein, in the battery pack, the voltage value of the battery cell connected to the jumper copper bar can change with the change of the preset conditions and the resistance value of the jumper copper bar;

[0032] An acquisition module, used for acquiring the highest voltage and the lowest voltage of the battery cells in the battery pack when the voltage value of the battery pack stops changing;

[0033] A determination module is used to determine the compensation resistance of the jumper copper bus according to the highest voltage, the lowest voltage and the preset condition.

[0034] In a third aspect, the present invention provides a test device for the internal resistance of a copper busbar in a battery, comprising a memory and a processor, wherein:

[0035] The memory is used to store computer programs;

[0036] The processor is used to read the program in the memory and execute the steps of the method for testing the internal resistance of the copper busbar inside the battery provided in the first aspect.

[0037] In a fourth aspect, the present invention provides a computer-readable storage medium having a readable computer program stored thereon, which, when executed by a processor, implements the steps of the method for testing the internal resistance of a copper busbar inside a battery as provided in the first aspect above.

[0038] Compared with the prior art, the method for testing the internal resistance of the copper bar inside a battery provided by the present invention has the following beneficial effects:

[0039] In the present invention, the voltage value of the battery pack is controlled to change under preset conditions. It can be understood that the battery cell connected to the jumper copper bar in the battery pack has a greater voltage change than the battery cell not connected to the jumper copper bar. In this way, when the voltage of the battery pack is increasing, the highest voltage of the battery cell in the battery pack is the voltage value of the battery cell connected to the jumper copper bar, and the lowest voltage of the battery cell in the battery pack is the voltage value of the battery cell not connected to the jumper copper bar; when the voltage of the battery pack is decreasing, the highest voltage of the battery cell in the battery pack is the voltage value of the battery cell not connected to the jumper copper bar, and the lowest voltage of the battery cell in the battery pack is the voltage value of the battery cell connected to the jumper copper bar. Therefore, it can be understood that when the voltage value of the battery pack stops changing, the voltage value of the highest voltage of the battery cell in the battery pack compared to the lowest voltage is the voltage variable brought by the jumper copper bar, so through this voltage variable and the preset conditions, the compensation resistance of the jumper copper bar can be naturally calculated. Furthermore, the present invention can obtain the compensation resistance of the jumper copper bar only by obtaining the voltage at both ends of the battery cell, thereby avoiding the manual measurement of the resistance of the jumper copper bar, and avoiding the problem that the compensation resistance of the jumper copper bar is manually measured in the prior art, which causes the battery pack to be unable to be measured after assembly, and when the battery pack structure is complex, the copper bar measurement space is insufficient, which easily leads to the inability to measure or the measurement position is not good, and other factors affect the accuracy of the measurement result. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only part of the embodiments of the present invention, rather than all of the embodiments. For ordinary technicians in this field, without paying creative work, other drawings obtained based on these drawings all fall within the scope of protection of the present invention.

[0041] Figure 1The present invention provides a flow chart of a method for testing the internal resistance of a copper busbar in a battery.

[0042] Figure 2 It is a flow chart of another method for testing the internal resistance of a copper busbar in a battery provided by an embodiment of the present invention.

[0043] Figure 3 The present invention is a flowchart of another method for testing the internal resistance of a copper busbar in a battery provided in an embodiment of the present invention.

[0044] Figure 4 It is a structural diagram of a device for testing the internal resistance of a copper busbar in a battery provided by an embodiment of the present invention.

[0045] Figure 5 It is a structural schematic diagram of a battery internal copper bar internal resistance testing device provided by an embodiment of the present invention.

[0046] Figure 6 It is a structural schematic diagram of a computer-readable storage medium provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0048] In order to make the description of the disclosed content more detailed and complete, the following is an illustrative description of the implementation mode and specific examples of the present invention; however, this is not the only form of implementing or applying the specific embodiments of the present invention. The implementation mode covers the features of multiple specific embodiments and the method steps and their sequence for constructing and operating these specific embodiments. However, other specific embodiments can also be used to achieve the same or equal functions and step sequences. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0049] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein.

[0050] In addition, in the description of the embodiments of the present invention, "multiple" means two or more than two, and other quantifiers are similar and should be understood. The preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. In addition, the embodiments of the present invention and the features therein may be combined with each other without conflict.

[0051] It should be noted that the test method in the embodiment of the present invention is applied to the internal resistance of the copper busbar inside the battery, but the test method can also be used to test the compensation resistance of other resistance elements, wherein the compensation resistance can be implemented based on the test steps of each embodiment of the present invention. The specific types of other resistance elements are not limited in detail here, and can be limited according to the actual needs during application.

[0052] like Figure 1 A method for testing the internal resistance of a copper busbar in a battery provided by an embodiment of the present invention is shown, and includes the following steps.

[0053] Step S110, collecting the voltage of the battery pack, and determining whether the jumper copper bus in the battery pack has an impact on the voltage of the battery pack.

[0054] It should be noted that the battery pack has multiple battery cells, so when collecting the voltage of the battery pack, it is necessary to collect the voltage of each battery cell in the battery pack.

[0055] It should be noted that the jumper copper busbar in the battery pack is a conductive component used to connect multiple battery cells and is usually used in the assembly of series or parallel battery packs.

[0056] It should be noted that the method for determining whether the jumper copper bar in the battery pack has an impact on the voltage of the battery pack can be any feasible method. For example, a control battery pack without a jumper copper bar can be set up, and the control battery pack can be discharged according to a constant discharge current, and the first voltage of the battery pack at the end of discharge can be recorded. Then, the battery pack connected to the jumper copper bar can be discharged according to the above-mentioned constant discharge current. If the second voltage of the battery pack at the end of discharge recorded is less than the first voltage, and the difference between the second voltage and the first voltage exceeds the preset threshold range, it can be determined that the jumper copper bar in the battery pack has an impact on the voltage of the battery pack.

[0057] Step S120: If yes, control the voltage value of the battery pack to change under a preset condition.

[0058] Wherein, in the battery pack, the voltage value of the battery cell connected to the jumper copper busbar can change with the change of the preset condition and the resistance value of the jumper copper busbar.

[0059] It should be noted that the voltage value of the battery cell connected to the jumper copper bar in this step can change with the change of preset conditions and the resistance of the jumper copper bar, which means that when the resistance of the jumper copper bar and other environmental factors remain unchanged, the voltage value of the jumper copper bar only changes with the change of preset conditions; when the preset conditions and other environmental factors remain unchanged, the voltage value of the jumper copper bar only changes with the change of the resistance of the jumper copper bar.

[0060] Step S130, when the voltage value of the battery pack stops changing, obtaining the highest voltage and the lowest voltage of the battery cells in the battery pack.

[0061] It is understandable that, since the cross-connect copper bar has resistance, when collecting the voltage of the battery pack, the impact of the resistance of the cross-connect copper bar will be reflected in the voltage of the battery pack. The highest and lowest voltages of the battery pack are easy to collect automatically, and the impact of the resistance of the cross-connect copper bar is naturally divided into two situations: increasing the voltage of the battery cells in the battery pack, or reducing the voltage of the battery cells in the battery pack. When the voltage of the battery cells in the battery pack is increased, the voltage value of the battery cells that are naturally increased is the highest voltage value of the battery pack, and the voltage values ​​of other battery cells that are not increased are the lowest voltage values ​​of the battery pack. Similarly, when the voltage of the battery cells in the battery pack is reduced, the voltage value of the battery cells that are naturally reduced is the lowest voltage value of the battery pack, and the voltage values ​​of other battery cells that are not reduced are the highest voltage values ​​of the battery pack.

[0062] Step S140, determining a compensation resistance value of the jumper copper bus according to the highest voltage, the lowest voltage and the preset condition.

[0063] It can be understood that according to step S130, it can be understood that the difference between the highest voltage and the lowest voltage of the battery pack is a value obtained by the combined influence of the preset conditions and the compensation resistance of the jumper copper busbar. In this way, when the difference between the highest voltage and the lowest voltage, and the preset conditions are known, the compensation resistance of the jumper copper busbar can be obtained based on the corresponding relationship between them.

[0064] In this way, in the embodiment of the present invention, the voltage value of the battery pack is controlled to change under preset conditions. It can be understood that the battery cells connected to the jumper copper bar in the battery pack have a greater voltage change than the battery cells not connected to the jumper copper bar. In this way, when the voltage of the battery pack is increasing, the highest voltage of the battery cells in the battery pack is the voltage value of the battery cells connected to the jumper copper bar, and the lowest voltage of the battery cells in the battery pack is the voltage value of the battery cells not connected to the jumper copper bar; when the voltage of the battery pack is decreasing, the highest voltage of the battery cells in the battery pack is the voltage value of the battery cells not connected to the jumper copper bar, and the lowest voltage of the battery cells in the battery pack is the voltage value of the battery cells connected to the jumper copper bar. Therefore, it can be understood that when the voltage value of the battery pack stops changing, the voltage value of the highest voltage of the battery cells in the battery pack compared to the lowest voltage is the voltage variable brought by the jumper copper bar. In this way, through this voltage variable and the preset conditions, the compensation resistance of the jumper copper bar can be naturally calculated. Furthermore, the present invention can obtain the compensation resistance of the jumper copper bar only by obtaining the voltage at both ends of the battery cell, thereby avoiding the manual measurement of the resistance of the jumper copper bar, and avoiding the problem that the compensation resistance of the jumper copper bar is manually measured in the prior art, which causes the battery pack to be unable to be measured after assembly, and when the battery pack structure is complex, the copper bar measurement space is insufficient, which easily leads to the inability to measure or the measurement position is not good, and other factors affect the accuracy of the measurement result.

[0065] In an optional implementation, collecting the voltage of the battery pack and determining whether the jumper copper bus in the battery pack has an impact on the voltage of the battery pack includes:

[0066] The battery pack is charged and discharged to determine whether the voltage change of the battery cells in the battery pack exceeds a normal level. If so, it is determined that the jumper copper busbar in the battery pack has an impact on the voltage of the battery pack.

[0067] It should be noted that “charging and discharging the battery pack” in this implementation refers to charging or discharging the battery pack.

[0068] It should be noted that the normal level of voltage change in the battery pack in this implementation is the voltage change of the battery cells in the battery pack when the battery pack is charged and discharged without the jumper copper bar. Therefore, it can be understood that when the battery pack is charged and discharged, if the voltage change of the battery cells in the battery pack exceeds the normal level, it can be known that the jumper copper bar has an impact on the voltage change of the battery pack. When collecting and utilizing the voltage of the battery pack, the compensation resistance value of the jumper copper bar needs to be considered.

[0069] In an optional implementation, Figure 2The flowchart of another method for testing the internal resistance of a copper bar in a battery provided by an embodiment of the present invention is shown, wherein charging and discharging the battery pack to determine whether the voltage change of the battery cells in the battery pack exceeds a normal level includes:

[0070] Step S210, charging the battery pack, and observing the highest voltage cell position where the highest voltage at the charging terminal of the battery pack is located during charging;

[0071] Step S220, discharging the battery pack, and observing the lowest voltage cell position where the lowest voltage at the end of discharge of the battery pack is located during discharge;

[0072] Step S230 , determining whether the highest voltage cell position is the same as the lowest voltage cell position, and if so, determining that the voltage change during charging and discharging in the battery pack exceeds a normal level.

[0073] It should be noted that in this implementation, the highest voltage at the end of charging refers to the highest voltage of the battery pack when the battery pack is fully charged, and the lowest voltage at the end of discharging refers to the lowest voltage of the battery pack when the battery pack is fully discharged. As a specific example, a full charge test can be performed on the battery pack by a charger to record the highest voltage cell position at the highest voltage at the end of charging when the battery pack is charged.

[0074] It should be noted that when the jumper copper bar affects the voltage collection of the battery pack, the battery pack is charged, and the battery cells of the battery pack connected to the jumper copper bar have a larger voltage increment at both ends than the battery cells of the battery pack not connected to the jumper copper bar. Naturally, when the battery pack is charged, the position of the highest voltage cell at the charging end of the battery pack is the position of the cell connected to the jumper copper bar. Similarly, when the battery pack is discharged, the position of the lowest voltage cell at the charging end of the battery pack is the position of the cell connected to the jumper copper bar. When the jumper copper bar has no effect on the voltage collection of the battery pack, the highest voltage cell position and the lowest voltage cell position of the battery pack are usually different. Therefore, when the highest voltage cell position and the lowest voltage cell position are the same, it can be determined that the voltage change of the battery pack during charging or discharging exceeds the normal level, and the jumper copper bar will affect the voltage collection of the battery pack.

[0075] In an optional implementation, if yes, controlling the voltage value of the battery pack to change under a preset condition includes:

[0076] If yes, a preset constant current value is used to discharge the battery pack, and the voltage value of the battery pack is controlled to change with the discharge time.

[0077] It should be noted that the constant current value preset in this implementation can be set according to specific needs during application and is not limited in detail here.

[0078] It can be understood that when the battery pack is discharged using a preset constant current value, when discharged to the final state, the lowest voltage value of the battery cells in the battery pack is the battery cells connected to the jumper copper bus, and the highest voltage value of the battery cells in the battery pack is the battery cells not connected to the jumper copper bus. In this way, by subtracting the lowest voltage value from the highest voltage value, the change in voltage of the jumper copper bus in the battery pack under the preset constant current value can be obtained. Further, based on the change in voltage of the jumper copper bus and the preset constant current value, the compensation resistance value of the jumper copper bus can be obtained using Ohm's law.

[0079] In an optional implementation, Figure 3 FIG. 1 is a flow chart of another method for testing the internal resistance of a copper bar in a battery provided by an embodiment of the present invention, wherein step S140 comprises:

[0080] Step S141, recording a first voltage difference between a maximum voltage and a minimum voltage of cells in the battery pack when the battery pack is discharged using a first constant current value;

[0081] Step S142, recording a second voltage difference between the highest voltage and the lowest voltage of the battery cells in the battery pack when the battery pack is discharged using a second constant current value;

[0082] Step S143, calculating and obtaining a constant current difference between the first constant current value and the second constant current value, and a voltage difference between the first voltage difference and the second voltage difference;

[0083] Step S144, calculating the quotient of the voltage difference and the constant current difference to obtain the compensation resistance of the jumper copper bus.

[0084] Wherein, the first constant current value is greater than the second constant current value.

[0085] Optionally, in this implementation, before discharging the battery pack, the capacity of the battery pack may be adjusted to a relatively stable plateau to facilitate normal subsequent discharge process. As a specific example, the capacity of the battery pack may be fifty percent.

[0086] It should be noted that the first constant current value and the second constant current value in the present implementation are both constant current values, and both the first constant current value and the second constant current value can be set according to specific needs during application, which are not limited in detail here.

[0087] It can be understood that when the battery pack is discharged using a constant current value, the voltage difference between the highest voltage and the lowest voltage of the battery cells in the battery pack is the voltage difference of the jumper copper bus when discharged for a certain period of time at the constant current value. From Ohm's law, it can be seen that the voltage difference divided by the constant current value can be used to obtain the compensation resistance of the jumper copper bus.

[0088] It can be further understood that in this implementation, when the constant current difference between the first constant current value and the second constant current value is used to discharge the battery pack, the voltage difference between the first voltage difference and the second voltage difference is the voltage difference when the battery pack is discharged using the constant current difference. Naturally, the compensation resistance of the cross-connected copper bar can be obtained by dividing the voltage difference by the constant current difference. Moreover, in this implementation, the constant current difference between the first constant current value and the second constant current value is used as the discharge current, which can avoid the problem that when the discharge device is controlled to discharge the battery pack with the first constant current value and the second constant current value, the theoretical value and the actual value of the output first constant current value and the second constant current value have errors due to the influence of the discharge device itself. Similarly, it can also naturally avoid the problem that when the voltage acquisition module collects the cell voltage, the theoretical value and the actual value of the collected first voltage difference and the second voltage difference have errors due to the influence of the voltage acquisition module itself, so that the measured compensation resistance of the cross-connected copper bar is more accurate.

[0089] It should be noted that in order to make the voltage difference corresponding to the cross-connected copper bar can be the voltage difference between the first voltage difference and the second voltage difference when discharging using the constant current difference, when the battery pack is discharged using the first constant current value and the second constant current value, the discharge time of the first constant current value and the second constant current value must be the same.

[0090] As a specific example, for example, the first constant current value is the maximum current value that can be used when discharging the battery pack. , the second constant current value is , place the battery pack in Discharge for 5 minutes and record the first voltage difference during the discharge process , place the battery pack in Discharge for 5 minutes and record the second voltage difference during the discharge process , and naturally calculate the compensation resistance of the last cross-connected copper bar .

[0091] In an optional implementation, the discharging the battery pack and observing the lowest voltage cell position where the lowest voltage at the end of discharge of the battery pack is located during the discharge includes:

[0092] The battery pack is discharged at a constant current using a preset multiple of the rated current until the battery system triggers a protection mechanism, and the position of the lowest voltage cell at the lowest discharge end voltage of the battery pack during discharge is observed.

[0093] It should be noted that the preset multiple in this implementation can be greater than 0 and less than 1, so as to prevent the discharge current of the battery pack from exceeding the rated current and causing problems with the battery pack. Optionally, in order to prevent the battery pack from being overheated due to excessive discharge current, which may cause the battery pack to be dangerous, the preset multiple can be set to 0.5.

[0094] In an optional implementation, after charging the battery pack and observing the highest voltage cell position where the highest voltage at the charging terminal of the battery pack is located during charging, and before discharging the battery pack and observing the lowest voltage cell position where the lowest voltage at the discharge terminal of the battery pack is located during discharging, the method further includes:

[0095] The battery pack is left to stand for a preset time until the battery pack is in a stable state.

[0096] It is understandable that after charging the battery pack, the overall voltage of the battery pack is too high and the overall state of the battery pack is unstable. If the battery pack is directly discharged at this time, the discharge process of the battery pack will be unsafe and it will be difficult to accurately control the discharge current. Therefore, in this implementation, the battery pack is left to stand for a preset time to stabilize the state of the battery pack, which can ensure the safety of the discharge process of the battery pack and make it easy to accurately control the discharge current. As a specific example, the preset time in this implementation can be 30 minutes.

[0097] Based on the above-mentioned method for testing the internal resistance of the copper busbar inside the battery, an embodiment of the present invention provides a device for testing the internal resistance of the copper busbar inside the battery, such as Figure 4 As shown in the figure, the test device for the internal resistance of the copper bar inside the battery includes:

[0098] A judgment module 410 is used to collect the voltage of the battery pack and judge whether the jumper copper bar in the battery pack has an impact on the voltage of the battery pack;

[0099] The control module 420 is used to control the voltage value of the battery pack to change under a preset condition, wherein, in the battery pack, the voltage value of the battery cell connected to the jumper copper bar can change with the change of the preset condition and the resistance value of the jumper copper bar;

[0100] An acquisition module 430 is used to acquire the highest voltage and the lowest voltage of the battery cells in the battery pack when the voltage value of the battery pack stops changing;

[0101] The determination module 440 is used to determine the compensation resistance of the jumper copper bus according to the highest voltage, the lowest voltage and the preset condition.

[0102] For other details about how the modules in the above-mentioned battery internal copper busbar internal resistance testing device implement the above-mentioned technical solution, please refer to the description of the battery internal copper busbar internal resistance testing method provided in the above-mentioned invention embodiment, which will not be repeated here.

[0103] Based on the above test method of the internal resistance of the copper bar inside the battery, such as Figure 5 As shown, an embodiment of the present invention further provides a schematic diagram of the structure of a test device for the internal resistance of a copper bar inside a battery, the test device comprising a processor 51 and a memory 52 coupled to the processor 51. The memory 52 stores a computer program, and when the computer program is executed by the processor 51, the processor 51 executes the steps of the method for testing the internal resistance of the copper bar inside the battery in the above embodiment.

[0104] For other details about how the processor 51 in the above-mentioned battery internal copper busbar internal resistance testing device implements the above-mentioned technical solution, please refer to the description of the battery internal copper busbar internal resistance testing method provided in the above-mentioned invention embodiment, which will not be repeated here.

[0105] Among them, the processor 51 can also be called a CPU (Central Processing Unit), and the processor 51 may be an integrated circuit chip with signal processing capabilities; the processor 51 can also be a general-purpose processor, DSP (Digital Signal Process), ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, among which the general-purpose processor can be a microprocessor or the processor 51 can also be any conventional processor, etc.

[0106] like Figure 6As shown, the embodiment of the present invention also provides a schematic diagram of the structure of a computer-readable storage medium, on which a readable computer program 61 is stored; wherein the computer program 61 can be stored in the above storage medium in the form of a software product, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, magnetic disk or optical disk, ROM (Read-Only Memory), RAM (Random Access Memory) and other media that can store program codes, or terminal devices such as computers, servers, mobile phones, and tablets.

[0107] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, which can be electrical, mechanical or other forms.

[0108] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0109] In addition, each functional module in each embodiment of the present invention may be integrated into a processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may be stored in a computer-readable storage medium.

[0110] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments may be implemented in the form of a computer program product.

[0111] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a server or data center that includes one or more available media integrated therein. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium), or a semiconductor medium (e.g., an SSD (solid state disk)).

[0112] The technical solution provided by the present invention is introduced in detail above. The present invention applies specific examples to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

[0113] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, optical storage, etc.) containing computer-usable program code.

[0114] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0115] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0116] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0117] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for testing the internal resistance of a copper busbar in a battery, characterized in that: include: Collecting the voltage of the battery pack, and determining whether the jumper copper busbar in the battery pack has an impact on the voltage of the battery pack; If yes, the voltage value of the battery pack is controlled to change under a preset condition, wherein, in the battery pack, the voltage value of the battery cell connected to the jumper copper bar can change with the change of the preset condition and the resistance value of the jumper copper bar; When the voltage value of the battery pack stops changing, obtaining the highest voltage and the lowest voltage of the battery cells in the battery pack; Determining the compensation resistance of the jumper copper bus according to the highest voltage, the lowest voltage and the preset condition; The collecting the voltage of the battery pack and determining whether the jumper copper bar in the battery pack has an impact on the voltage of the battery pack includes: The battery pack is charged and discharged to determine whether the voltage change of the battery cells in the battery pack exceeds a normal level, and if so, it is determined that the jumper copper busbar in the battery pack has an impact on the voltage of the battery pack; The charging and discharging of the battery pack to determine whether the voltage change of the battery cells in the battery pack exceeds a normal level includes: Charging the battery pack, and observing the position of the highest voltage cell at the charging terminal of the battery pack when charging; Discharging the battery pack, and observing the lowest voltage cell position where the lowest voltage at the end of discharge of the battery pack is located during discharge; Determining whether the position of the highest voltage battery cell is the same as the position of the lowest voltage battery cell, and if so, determining that the voltage change during charging and discharging in the battery pack exceeds a normal level; The step of determining the compensation resistance of the jumper copper busbar according to the highest voltage, the lowest voltage and the preset condition comprises: Recording a first voltage difference between a highest voltage and a lowest voltage of cells in the battery pack when the battery pack is discharged using a first constant current value; recording a second voltage difference between a highest voltage and a lowest voltage of cells in the battery pack when the battery pack is discharged using a second constant current value, wherein the first constant current value is greater than the second constant current value; Calculating a constant current difference between the first constant current value and the second constant current value, and a voltage difference between the first voltage difference and the second voltage difference; The quotient of the voltage difference and the constant current difference is calculated to obtain the compensation resistance of the jumper copper busbar.

2. The method for testing the internal resistance of the copper bar inside the battery according to claim 1, characterized in that: If yes, then controlling the voltage value of the battery pack to change under a preset condition comprises: If yes, a preset constant current value is used to discharge the battery pack, and the voltage value of the battery pack is controlled to change with the discharge time.

3. The method for testing the internal resistance of the copper bar inside the battery according to claim 1, characterized in that: The step of discharging the battery pack and observing the position of the lowest voltage cell at the lowest discharge end voltage of the battery pack during discharge includes: The battery pack is discharged at a constant current using a preset multiple of the rated current until the battery system triggers a protection mechanism, and the position of the lowest voltage cell at the lowest discharge end voltage of the battery pack during discharge is observed.

4. The method for testing the internal resistance of the copper bar inside the battery according to claim 1, characterized in that: After charging the battery pack and observing the highest voltage cell position where the highest voltage at the charging terminal of the battery pack is located during charging, and before discharging the battery pack and observing the lowest voltage cell position where the lowest voltage at the discharging terminal of the battery pack is located during discharging, the method further includes: The battery pack is left to stand for a preset time until the battery pack is in a stable state.

5. A device for testing the internal resistance of a copper bar inside a battery, the device being used to implement the steps of the method for testing the internal resistance of a copper bar inside a battery as claimed in any one of claims 1 to 4, characterized in that: include: A judgment module, used for collecting the voltage of the battery pack and judging whether the jumper copper bar in the battery pack has an impact on the voltage of the battery pack; A control module, if used to control the voltage value of the battery pack to change under preset conditions, wherein, in the battery pack, the voltage value of the battery cell connected to the jumper copper bar can change with the change of the preset conditions and the resistance value of the jumper copper bar; An acquisition module, used for acquiring the highest voltage and the lowest voltage of the battery cells in the battery pack when the voltage value of the battery pack stops changing; A determination module is used to determine the compensation resistance of the jumper copper bus according to the highest voltage, the lowest voltage and the preset condition.

6. A test device for the internal resistance of the copper bar inside a battery, characterized in that: comprising a memory and a processor, wherein: The memory is used to store computer programs; The processor is used to read the computer program in the memory and execute the steps of any method for testing the internal resistance of the copper bar inside the battery as described in claims 1-4.

7. A computer-readable storage medium, characterized in that: A readable computer program is stored thereon, and when the program is executed by a processor, the steps of the method for testing the internal resistance of the copper bar inside a battery as described in any one of claims 1 to 4 are implemented.

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