Resistance testing method, device and system

Abstract

The invention discloses a resistance value testing method, device and system. The method comprises the steps that an initial calculation model is obtained, the initial calculation model can conduct electrical performance simulation on a mechanical part, and the initial calculation model comprises a part with conductivity to be determined; when a probe of the resistance meter is placed at preset positions on the two sides of the electric conductivity to-be-determined part, actually measured resistance parameters of the electric conductivity to-be-determined part of the mechanical part obtained through actual measurement are obtained; and performing simulation in the initial calculation model by adopting a measurement method which is the same as the actual measurement method to obtain a simulation resistance parameter containing a conductivity-to-be-determined part of the mechanical part, and adjusting the material attribute of the conductivity-to-be-determined part of the mechanical part until the difference between the simulation resistance parameter and the actually measured resistance parameter is smaller than a set threshold value, so as to obtain the conductivity-to-be-determined part of the mechanical part. Determining an optimization calculation model; and performing electrical performance simulation on the mechanical part in the optimization calculation model to obtain the resistance value of the to-be-determined part of the conductivity of the mechanical part, thereby improving the accuracy of the resistance value test.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and in particular to a method, apparatus and system for testing resistance. Background Technology

[0002] With the rapid development of the new energy industry, electric vehicles have entered a period of high-speed growth. Lithium-ion batteries, as a core component of electric vehicles, have undergone several technological iterations. However, limited by the energy density of lithium battery materials, the driving range of electric vehicles has been difficult to achieve significant breakthroughs, leading to persistent range anxiety. Current technologies can alleviate range anxiety by increasing the charging rate and accelerating recharging speed.

[0003] As the charging rate increases, the temperature of the battery cell and battery pack rises rapidly in the short term. Optimizing the internal resistance of the battery cell can reduce the heat generated during charging, thus keeping it within a safe operating temperature range. The internal resistance of a battery cell consists of two parts: ohmic resistance and electrochemical reaction resistance. The resistance of mechanical components accounts for a large proportion of the ohmic internal resistance; reducing the resistance of mechanical components can reduce heat generation in the battery cell. However, there are components with uncertain resistivity in mechanical components, making their resistance measurements inaccurate. Summary of the Invention

[0004] This invention provides a method, apparatus, and system for testing resistance values ​​to improve the accuracy of resistance testing of the mechanical components of battery cells.

[0005] According to one aspect of the present invention, a method for testing resistance is provided, applied to the mechanical components of a battery cell; the method includes:

[0006] An initial calculation model is obtained, which is capable of simulating the electrical performance of the mechanical component. The initial calculation model includes a part whose conductivity needs to be determined.

[0007] The measured resistance parameters of the mechanical part whose conductivity needs to be determined are obtained by actually measuring the part with the probe of the ohmmeter placed at preset positions on both sides of the part with the conductivity to be determined.

[0008] Using the same measurement method as the actual measurement, simulation is performed in the initial calculation model to obtain the simulated resistance parameters of the part of the mechanical component whose conductivity needs to be determined. The material properties of the part of the mechanical component whose conductivity needs to be determined are adjusted until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, so as to determine the optimized calculation model.

[0009] The electrical performance of the mechanical component is simulated in the optimized calculation model to obtain the resistance value of the part of the mechanical component whose conductivity needs to be determined.

[0010] Optionally, the portion of the mechanical component whose conductivity needs to be determined includes the welded area;

[0011] The process of obtaining the measured resistance parameters of the mechanical component with undetermined conductivity obtained by placing the probe of the ohmmeter at preset positions on both sides of the portion with undetermined conductivity includes:

[0012] The first and second sets of probes of the ohmmeter are placed on both sides of the welding area of ​​the mechanical part, and the measured resistance parameters including the welding area are obtained.

[0013] In addition, in the step of determining the optimization calculation model, the material properties of the welding area are adjusted.

[0014] Optionally, the mechanical component includes: a pole at the top, a rivet block riveted to the outer edge of the top of the pole, an adapter piece at the bottom, a first welding area between the pole and the adapter piece, and a second welding area at the bottom of the adapter piece; wherein the first welding area and the second welding area are the portions of the mechanical component whose conductivity is yet to be determined.

[0015] The step of placing the first and second sets of probes of the ohmmeter on both sides of the welding area of ​​the mechanical component, and actually measuring the measured resistance parameters including the welding area, includes:

[0016] The first set of probes of the ohmmeter is placed on the top of the pole or the top of the riveting block, and the second set of probes of the ohmmeter is placed on the bottom of the adapter piece. The actual resistance parameters including the first welding area are obtained by actual measurement.

[0017] And / or, place the first set of probes of the ohmmeter on the top of the pole or the top of the rivet block, and place the second set of probes of the ohmmeter on the bottom of the second welding area, and actually measure the measured resistance parameters including the first welding area and the second welding area.

[0018] Optionally, the first welding area is a laser welding area or an ultrasonic welding area;

[0019] And / or, the second welding area is a laser welding area or an ultrasonic welding area.

[0020] Optionally, the mechanical component is a positive electrode mechanical component, the first set of probes is a positive electrode probe, and the second set of probes is a negative electrode probe;

[0021] Alternatively, the mechanical component may be a negative electrode mechanical component, the first set of probes may be a negative electrode probe, and the second set of probes may be a positive electrode probe.

[0022] Optionally, obtaining the measured resistance parameters of the mechanical component whose conductivity is to be determined by actually measuring when the probe of the ohmmeter is placed at preset positions on both sides of the portion whose conductivity is to be determined includes:

[0023] For the measurement of the same part of the mechanical component, the probe of the ohmmeter is placed at at least two preset positions, and at least two measured resistance parameters of the same part of the mechanical component are obtained by actual measurement.

[0024] Optionally, the step involves using the same measurement method as the actual measurement to simulate and obtain the simulated resistance parameters of the portion of the mechanical component whose conductivity needs to be determined in the initial calculation model, and adjusting the material properties of the portion of the mechanical component whose conductivity needs to be determined until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, in order to determine the optimized calculation model, including:

[0025] For the measurement of the same part of the mechanical component, the same measurement method as the actual measurement is adopted. Simulation is performed in the initial calculation model to obtain the simulated resistance parameters of the same part of the mechanical component. The material properties of the same part of the mechanical component are adjusted until the difference between each simulated resistance parameter and the corresponding measured resistance parameter is less than the set threshold.

[0026] The material properties obtained from each optimization are statistically calculated to obtain the optimal material properties, thereby determining the optimization calculation model.

[0027] Optionally, the step of performing electrical performance simulation on the mechanical component in the optimized calculation model to obtain the resistance value of the portion of the mechanical component whose conductivity needs to be determined includes:

[0028] In the optimized calculation model, the mechanical component is assigned an electric current and a ground plane;

[0029] By extracting the electrical parameters of the portion of the mechanical component whose conductivity needs to be determined, the resistance value of that portion is obtained; the electrical parameters include: voltage, current density, and / or heat generation.

[0030] Optionally, when performing electrical performance simulation on the mechanical component in the optimization calculation model to obtain the resistance value of the portion of the mechanical component whose conductivity needs to be determined, the method further includes:

[0031] The individual resistance values ​​of each part of the mechanical component and / or the overall resistance value of the mechanical component are obtained.

[0032] Optionally, obtaining the initial computational model includes:

[0033] The initial calculation model is obtained by scanning the physical object of the mechanical part using a 3D scanner.

[0034] Alternatively, the mechanical part can be modeled using 3D drawing software to obtain the initial calculation model.

[0035] According to another aspect of the present invention, a resistance testing device is provided, applied to a mechanical component of a battery cell; the device includes:

[0036] The model acquisition module is used to acquire an initial calculation model, which is capable of simulating the electrical performance of the mechanical component. The initial calculation model includes a part whose conductivity needs to be determined.

[0037] The measured value acquisition module is used to acquire the measured resistance parameters of the mechanical part whose conductivity is to be determined when the probe of the ohmmeter is placed at preset positions on both sides of the part whose conductivity is to be determined.

[0038] The model optimization module is used to perform simulation in the initial calculation model using the same measurement method as the actual measurement to obtain the simulated resistance parameters of the part of the mechanical component whose conductivity needs to be determined, and to adjust the material properties of the part of the mechanical component whose conductivity needs to be determined until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, so as to determine the optimized calculation model.

[0039] The resistance determination module is used to perform electrical performance simulation on the mechanical component in the optimization calculation model to obtain the resistance value of the part of the mechanical component whose conductivity needs to be determined.

[0040] According to another aspect of the present invention, a resistance testing system is provided, comprising: a ohmmeter and a computer; the ohmmeter is used to measure the measured resistance parameters of various parts of the mechanical component; the computer includes:

[0041] At least one processor; and

[0042] A memory communicatively connected to the at least one processor; wherein,

[0043] The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the resistance testing method according to any embodiment of the present invention.

[0044] This invention provides an initial computational model that includes the portion of conductivity to be determined and allows for electrical performance simulation. Then, using the same measurement method, both actual and simulated measurements are performed on the mechanical component. In the simulation measurement, the material properties of the portion with undetermined conductivity can be adjusted to match the actual measurement results, thus determining the material properties of that portion and obtaining an optimized computational model. Further, electrical performance simulations are performed on the mechanical component within the optimized model. Since the material properties of all parts of the mechanical component are already known, the resistance value of the portion with undetermined conductivity can be obtained. In summary, this invention improves the accuracy of resistance testing for mechanical components.

[0045] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 A schematic flowchart of a resistance testing method provided in an embodiment of the present invention;

[0048] Figure 2 An exploded view of a mechanical component provided in an embodiment of the present invention;

[0049] Figure 3 A schematic diagram of the structure of a mechanical component provided in an embodiment of the present invention;

[0050] Figure 4 A flowchart illustrating another resistance testing method provided in an embodiment of the present invention;

[0051] Figure 5 A flowchart illustrating another resistance testing method provided in an embodiment of the present invention;

[0052] Figure 6 This is a schematic diagram of another mechanical component provided in an embodiment of the present invention;

[0053] Figure 7 This is a schematic diagram of another mechanical component provided in an embodiment of the present invention;

[0054] Figure 8 A schematic diagram of a resistance testing device provided for implementation of the present invention;

[0055] Figure 9 This is a schematic diagram of the structure of a resistance testing system provided in an embodiment of the present invention;

[0056] Figure 10 This is a schematic diagram of the structure of a computer provided in an embodiment of the present invention. Detailed Implementation

[0057] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0058] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0059] This invention provides a resistance testing method for mechanical components with undetermined conductivity. The method is applicable to testing the resistance of mechanical components in battery cells. The method can be executed by a resistance testing device, which can be implemented in hardware and / or software and can be configured in the computer of the resistance testing system. Figure 1 This is a flowchart illustrating a resistance testing method provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes the following steps:

[0060] S110. Obtain the initial calculation model, which can simulate the electrical performance of mechanical parts.

[0061] In subsequent steps, the resistance test of the mechanical components is achieved through model simulation. Since resistance falls under the category of electrical properties, a computational model capable of simulating electrical performance is required. Therefore, the resistance test in this embodiment of the invention relies on the accuracy of the computational model. For mechanical components, their shape properties and the material properties of some structures can be accurately determined; therefore, the conductivity properties of these parts are clear. However, mechanical components often contain parts with unclear conductivity, referred to as the conductivity-undefined portion. For example, in welded areas between different structures, there are often contact gaps and surface oxide layers, making their conductivity properties unclear; similarly, in laminated structures pressed from the same material, the conductivity properties of their contact resistance are also unclear. Given that the computational model contains the conductivity-undefined portion, this computational model is considered an initial computational model.

[0062] S120. Obtain the measured resistance parameters of the mechanical part whose conductivity is to be determined by actually measuring when the probe of the ohmmeter is placed at a preset position on both sides of the part whose conductivity is to be determined.

[0063] This step involves actually measuring the physical mechanical part. The resistance parameter can be either resistance or resistivity, determined by the display of the specific ohmmeter used. If the ohmmeter displays resistance, then the measured resistance parameter is the measured resistance; if the ohmmeter displays resistivity, then the measured resistance parameter is the measured resistivity. In subsequent steps, the selection of the simulated resistance parameter should be consistent with the measured resistance parameter. In the following embodiment, we will use the example where both the measured and simulated resistance parameters are resistance values.

[0064] This ohmmeter can be any type of ohmmeter capable of accurately measuring structural resistance, such as a high-precision micro-ohmmeter using the four-probe method. A four-probe ohmmeter has four test probes: a positive voltage probe, a negative voltage probe, a positive current probe, and a negative current probe. The positive voltage probe and the positive current probe form one group, called the positive probe; the negative voltage probe and the negative current probe form another group, called the negative probe. The positive and negative probes are placed on opposite sides of the part being measured. The choice of preset positions affects the actual resistance measurement result; generally, the greater the distance between the two sets of probes, the greater the resistance; the closer the two sets of probes, the smaller the resistance.

[0065] For example, the portion where conductivity needs to be determined is the welded area. The first set of probes (e.g., positive probes) and the second set of probes (e.g., negative probes) of the ohmmeter are placed on both sides of the welded area of ​​the mechanical part, and the measured resistance parameters including the welded area are obtained by actual measurement.

[0066] S130. Using the same measurement method as the actual measurement, simulation is performed in the initial calculation model to obtain the simulated resistance parameters of the part containing the mechanical parts whose conductivity needs to be determined. The material properties of the part containing the mechanical parts whose conductivity needs to be determined are adjusted until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, so as to determine the optimized calculation model.

[0067] In this context, "the same measurement method as the actual measurement" means that the measurement method and / or measurement location are the same. The measurement method can be, for example, a two-probe method, a three-probe method, a four-probe method, a capacitance-voltage method, or an extended resistance method. The measurement location only needs to be on both sides of the part to be determined. In some embodiments, the actual measurement uses the four-probe method, and the initial calculation model also uses the four-probe method. In other embodiments, the actual measurement places the positive probe at the center of the structure on one side of the part whose conductivity is to be determined, and the negative probe at the center of the structure on the other side of the part whose conductivity is to be determined; the initial calculation model also measures the resistance from the center of one side of the structure to the center of the other side of the part whose conductivity is to be determined. In this embodiment of the invention, there are no strict requirements for the measurement location because the material properties on both sides of the part to be determined are usually well-defined, and therefore its conductivity is also well-defined. Regardless of where the probe is placed in the part with well-defined conductivity, its resistance can be accurately simulated. The only unknown quantity is the conductivity of the part to be determined. Therefore, by making the simulation result equal to the measured result, the material properties of the part whose conductivity is to be determined can be determined. Adjusting material properties can involve directly adjusting conductivity, or it can involve adjusting the chemical content of the material. For example, the conductivity to be determined is in the welding area, and the material properties of the welding area are adjusted.

[0068] Understandably, the closer the simulated resistance is to the measured resistance, the more accurate the material properties of the conductivity portion to be determined after adjustment, and thus the more accurate the optimized calculation model. Ideally, the simulated resistance should be equal to the measured resistance. However, in practical applications, there are often situations where, despite repeated adjustments to material properties, the simulated and measured resistances remain unequal. Therefore, in practical applications, a threshold value can be set to characterize the difference between the simulated and measured resistance values. A larger threshold value can improve the efficiency of resistance testing; a smaller threshold value can improve the accuracy of resistance testing.

[0069] S140. Perform electrical performance simulation on the mechanical parts in the optimized calculation model to obtain the resistance value of the part of the mechanical parts whose conductivity needs to be determined.

[0070] Since the material properties containing conductivity of the part to be determined have been determined in the aforementioned steps S120 and S130, the material properties of all parts of the mechanical component in the optimization calculation model are clear, thus enabling accurate electrical performance simulation to be performed, obtaining the resistance value of the part of the mechanical component whose conductivity needs to be determined, and also obtaining the individual resistance value of each part of the mechanical component and / or the overall resistance value of the mechanical component.

[0071] This invention provides an initial computational model that includes the portion of conductivity to be determined and allows for electrical performance simulation. Then, using the same measurement method, both actual and simulated measurements are performed on the mechanical component. In the simulation measurement, the material properties of the portion with undetermined conductivity can be adjusted to match the actual measurement results, thus determining the material properties of that portion and obtaining an optimized computational model. Further, electrical performance simulations are performed on the mechanical component within the optimized model. Since the material properties of all parts of the mechanical component are already known, the resistance value of the portion with undetermined conductivity can be obtained. In summary, this invention improves the accuracy of resistance testing for mechanical components.

[0072] To more clearly illustrate the resistance testing method provided in the embodiments of the present invention, the following description uses the structure of a mechanical component as an example, but this is not intended to limit the present invention.

[0073] Figure 2 An exploded view of a mechanical component provided in an embodiment of the present invention. Figure 3 This is a schematic diagram of the structure of a mechanical component provided in an embodiment of the present invention. See also... Figure 2 and Figure 3 In one embodiment, the mechanical component includes: a top electrode post 220, a riveting block 210 riveted to the top outer edge of the electrode post 220, a bottom adapter piece 230, a first welding area between the electrode post 220 and the adapter piece 230, and a second welding area at the bottom of the adapter piece 230. The first welding area 240 has a first solder mark 241, and the second welding area has a second solder mark 251. Because of contact gaps and surface oxide layers, the overall conductivity of the welding areas is uncertain; therefore, the first welding area 240 and the second welding area 250 are the parts of the mechanical component whose conductivity needs to be determined.

[0074] Optionally, the first welding area 240 is a laser welding area or an ultrasonic welding area; the second welding area 250 is a laser welding area or an ultrasonic welding area. In one embodiment, the first welding area 240 is a laser welding area, and the second welding area 250 is an ultrasonic welding area.

[0075] Based on the above embodiments, optionally, when there is only one part in the mechanical component whose conductivity needs to be determined, it is only necessary to perform actual measurement and simulation measurement tests on the part whose conductivity needs to be determined; when there are at least two parts in the mechanical component whose conductivity needs to be determined, it is necessary to perform actual measurement and simulation measurement tests on each part whose conductivity needs to be determined, so as to obtain the material properties of each part whose conductivity needs to be determined.

[0076] Figure 4 This is a schematic flowchart illustrating another resistance testing method provided in an embodiment of the present invention. See also... Figures 2-4 In one embodiment, optionally, the portion whose conductivity needs to be determined includes a first welded region 240 and a second welded region 250, and the testing method includes the following steps:

[0077] S210. Obtain the initial calculation model, which can simulate the electrical performance of mechanical parts; the initial calculation model includes a first welding area 240 and a second welding area 250 whose conductivity is to be determined.

[0078] S220: The first set of probes of the ohmmeter is placed on the top of the pole 220 or the top of the riveting block 210, and the second set of probes of the ohmmeter is placed on the bottom of the adapter piece 230. The actual resistance parameters including the first welding area 240 are obtained by actual measurement.

[0079] The resistance parameter is measured using the four-probe method. The mechanical components in the battery cell conduct electricity, and current flows through these components during normal use, such as charging. In this embodiment, placing the first set of probes on the top of the terminal 220 or the top of the riveting block 210, and placing the second set of probes on the bottom of the adapter plate 230, simulates the actual current flow through the mechanical components during battery cell use, resulting in more accurate resistance parameters.

[0080] Optionally, if the mechanical component is a positive mechanical component, the current flows from the top to the bottom of the mechanical component, the first set of probes is a positive probe, and the second set of probes is a negative probe, thereby simulating current flow; if the mechanical component is a negative mechanical component, the current flows from the bottom to the top of the mechanical component, the first set of probes is a negative probe, and the second set of probes is a positive probe, thereby simulating current flow.

[0081] Specifically, in this embodiment, the measured resistance parameters include the riveting block 210, the pole 220, the first welding area 240, and the adapter piece 230.

[0082] S230. Using the same measurement method as the actual measurement, simulation is performed in the initial calculation model to obtain the simulated resistance parameters including the first welding area 240, and the material properties of the first welding area 240 are adjusted until the difference between the simulated resistance parameters and the measured resistance parameters is less than the set threshold.

[0083] Among them, the material properties of the riveting block 210, the pole 220 and the adapter piece 230 are known, only the material properties of the first welding area 240 are unknown. In this resistance parameter, only the resistance or resistivity of the first welding area 240 is unknown. The resistance or resistivity of the first welding area 240 can be obtained by calculation.

[0084] S240. Place the first set of probes of the ohmmeter on the top of the pole 220 or the top of the riveting block 210, and place the second set of probes of the ohmmeter on the bottom of the second welding area 250. The actual resistance parameters including the first welding area 240 and the second welding area 250 are obtained by actual measurement.

[0085] Specifically, in this embodiment, the measured resistance parameters include the riveting block 210, the pole 220, the first welding area 240, the adapter piece 230, and the second welding area 240.

[0086] S250. Using the same measurement method as the actual measurement, simulation is performed in the initial calculation model to obtain the simulated resistance parameters including the second welding area 250. The material properties of the second welding area 250 are adjusted until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, so as to determine the optimized calculation model.

[0087] Among them, the material properties of the riveting block 210, the pole 220 and the adapter piece 230 are known, the material properties of the first welding area 240 are known in S230, only the material properties of the second welding area 250 are unknown. In this resistance parameter, only the resistance or resistivity of the second welding area 250 is unknown. The resistance or resistivity of the second welding area 250 can be obtained by calculation.

[0088] S260. Perform electrical performance simulation on the mechanical components in the optimized calculation model to obtain the individual resistance values ​​of each part of the mechanical components and / or the overall resistance value of the mechanical components.

[0089] Optionally, in the optimization calculation model, current and ground plane are assigned to the mechanical components; the resistance values ​​of each part or the whole of the mechanical components are obtained by extracting the electrical parameters of each part or the whole of the mechanical components; the electrical parameters include: voltage, current density and / or heat generation. Specifically, the riveting block 210 or the pole 220 can be used as the ground plane, and a set current value can be given in the second welding area 250, so that the resistance values ​​of each part or the whole can be obtained through simulation.

[0090] Therefore, through the above steps, the embodiments of the present invention clarify the material properties of the first welding area 240 and the second welding area 250, thereby improving the accuracy of resistance testing of mechanical components. Furthermore, as can be seen from the above steps, the testing method provided by the embodiments of the present invention can simulate current flow in the actual application scenarios of mechanical components, thereby further improving the accuracy of resistance testing of mechanical components.

[0091] Based on the above embodiments, the embodiments of the present invention may optionally further optimize the actual measurement steps and the simulation measurement steps to further improve the accuracy of mechanical component resistance testing.

[0092] Figure 5 This is a schematic flowchart illustrating another resistance testing method provided in an embodiment of the present invention. See also... Figure 5 Optionally, the testing method includes the following steps:

[0093] S310. Obtain the initial calculation model, which can simulate the electrical performance of mechanical parts.

[0094] S320. Obtain measurements for the same part of a mechanical component by placing the probe of a ohmmeter at at least two preset positions and performing actual measurements to obtain at least two measured resistance parameters for the same part of the mechanical component.

[0095] The closer the simulated resistance parameters are to the measured resistance parameters, the more accurate the material properties of the conductivity portion to be determined after adjustment, and thus the more accurate the optimized calculation model. However, in practical applications, there are often situations where, despite repeated adjustments to material properties, the simulated resistance parameters and the measured resistance parameters remain unequal. This invention improves measurement accuracy through multiple measurements.

[0096] Taking the measurement of the first welding area as an example, Figure 6 For another structural schematic diagram of a mechanical component provided in an embodiment of the present invention, see [link to schematic diagram]. Figure 6 , Figure 6 To be Figure 3The diagram shows the structure after the mechanical components in the diagram have been flipped up from top to bottom. In one embodiment, the positive probe (including a positive voltage probe and a positive current probe) is fixed to the top of the terminal post 220, and the position of the negative probe (including a negative voltage probe and a negative current probe) at the bottom of the adapter piece 230 is adjusted. Specifically, when the negative probe is placed at position 231, a first measured resistance parameter can be obtained; when the negative probe is placed at position 232, a second measured resistance parameter can be obtained; when the negative probe is placed at position 233, a third measured resistance parameter can be obtained; when the negative probe is placed at position 234, a fourth measured resistance parameter can be obtained; and when the negative probe is placed at position 235, a fifth measured resistance parameter can be obtained.

[0097] Taking the measurement of the second welding area as an example, Figure 7 For another structural schematic diagram of a mechanical component provided in an embodiment of the present invention, see [link to schematic diagram]. Figure 7 , Figure 7 For another way Figure 3 The diagram shows the structure after the mechanical components in the diagram have been flipped at the top and bottom. In one embodiment, the positive probe (including a positive voltage probe and a positive current probe) is fixed at the top of the electrode post 220, and the position of the negative probe (including a negative voltage probe and a negative current probe) at the bottom of the second solder mark 251 is adjusted. Specifically, when the negative probe is placed at position 252, a first measured resistance parameter can be obtained; when the negative probe is placed at position 253, a second measured resistance parameter can be obtained; when the negative probe is placed at position 254, a third measured resistance parameter can be obtained; when the negative probe is placed at position 255, a fourth measured resistance parameter can be obtained; when the negative probe is placed at position 256, a fifth measured resistance parameter can be obtained; when the negative probe is placed at position 257, a sixth measured resistance parameter can be obtained; and when the negative probe is placed at position 258, a seventh measured resistance parameter can be obtained.

[0098] It should be noted that in the above embodiments, the actual measurement of the first welding area involves placing the negative electrode probe at the bottom of the adapter piece 230. This arrangement is because the first welding area is located between the electrode post 220 and the adapter piece 230, and placing the probe on the first solder mark would be difficult. Therefore, placing the negative electrode probe at the bottom of the adapter piece 230 helps to reduce the difficulty of operation. The actual measurement of the second welding area involves placing the negative electrode probe on the second solder mark 251. This arrangement is because the first welding area is not only electrically connected to the adapter piece 230, but also to the electrode tab (…). Figure 7(Not shown) Electrical connection, and the tab is made of multiple layers of electrode sheets pressed together, with contact resistance between them, which is also uncertain. If the negative probe is placed on the tab, the material properties of the second solder mark 251 cannot be accurately measured. Therefore, placing the negative probe on the second solder mark 251 to determine the material properties of the second solder area is beneficial to improving the accuracy of the test. In addition, in this step, the desired resistance parameter is the conductivity of the second solder area, not the overall resistance of the second solder area. Therefore, even if the position of the negative probe causes the test current to not pass through the entire second solder mark 251, it will not affect the accuracy of the test.

[0099] S330. For the measurement of the same part in the mechanical part, the same measurement method as the actual measurement is adopted. Simulation is performed in the initial calculation model to obtain the simulated resistance parameters of the same part containing the mechanical part. The material properties of the same part of the mechanical part are adjusted until the difference between each simulated resistance parameter and the corresponding measured resistance parameter is less than the set threshold.

[0100] Taking the measurement of the first welding area as an example, see below. Figure 6 ,Will Figure 6 The structure shown is considered as a mechanical component in the computational model. Similar to S320, the positive probe (including the positive voltage probe and the positive current probe) is fixed to the top of the electrode post 220, and the position of the negative probe (including the negative voltage probe and the negative current probe) at the bottom of the adapter piece 230 is adjusted. Specifically, when the negative probe is placed at position 231, the material properties of the first welding area are adjusted so that the difference between the first simulated resistance parameter and the first measured resistance parameter is less than a set threshold; when the negative probe is placed at position 232, the difference between the second simulated resistance parameter and the second measured resistance parameter is less than a set threshold; when the negative probe is placed at position 233, the difference between the third simulated resistance parameter and the third measured resistance parameter is less than a set threshold; when the negative probe is placed at position 234, the difference between the fourth simulated resistance parameter and the fourth measured resistance parameter is less than a set threshold; and when the negative probe is placed at position 235, the difference between the fifth simulated resistance parameter and the fifth measured resistance parameter is less than a set threshold.

[0101] Taking the measurement of the second welding area as an example, see below. Figure 7 ,Will Figure 7The structure shown is considered as a mechanical component in the computational model. Similar to S320, the positive probe (including the positive voltage probe and the positive current probe) is fixed to the top of the electrode post 220, and the position of the negative probe (including the negative voltage probe and the negative current probe) at the bottom of the second solder mark 251 is adjusted. Specifically, when the negative probe is placed at position 252, the material properties of the second solder area are adjusted so that the difference between the first simulated resistance parameter and the first measured resistance parameter is less than a set threshold; when the negative probe is placed at position 253, the material properties of the second solder area are adjusted so that the difference between the second simulated resistance parameter and the second measured resistance parameter is less than a set threshold; when the negative probe is placed at position 254, the material properties of the second solder area are adjusted so that the difference between the third simulated resistance parameter and the third measured resistance parameter is less than a set threshold; when the negative probe is placed at position 255, the material properties of the second solder area are adjusted... The material properties of the second welding area are adjusted so that the difference between the fourth simulated resistance parameter and the fourth measured resistance parameter is less than a set threshold when the negative probe is placed at position 256. Similarly, when the negative probe is placed at position 257, the material properties of the second welding area are adjusted so that the difference between the sixth simulated resistance parameter and the sixth measured resistance parameter is less than a set threshold. Finally, when the negative probe is placed at position 258, the material properties of the second welding area are adjusted so that the difference between the seventh simulated resistance parameter and the seventh measured resistance parameter is less than a set threshold.

[0102] S340. Perform statistical calculations on the material properties of each optimization to obtain the optimal material properties, and determine the optimization calculation model.

[0103] Taking the measurement of the first welded area as an example, the material property is conductivity. The conductivity of the first welded area under the first to fifth conditions is statistically calculated. Specifically, the conductivity of the first welded area is set such that the error between each simulated resistance parameter and the measured resistance parameter is less than a preferred threshold in the five tests.

[0104] Taking the measurement of the second welded area as an example, the material property is conductivity. The conductivity of the second welded area under the first to seventh conditions is statistically calculated. Specifically, the conductivity of the second welded area is set such that the error between each simulated resistance parameter and the measured resistance parameter is less than a preferred threshold in the seven tests.

[0105] S350. Perform electrical performance simulation on the mechanical parts in the optimized calculation model to obtain the resistance value of the part of the mechanical parts whose conductivity needs to be determined.

[0106] Therefore, by taking the above steps and eliminating errors through multiple measurements of the same part, the accuracy of mechanical component resistance testing is further improved in this embodiment of the invention.

[0107] It should be noted that in the above embodiments, the measurement of the conductivity of the first welding area and the second welding area is used as an example for illustration, and is not intended to limit the present invention. In other embodiments, the conductivity of the contact resistance in the tabs or other components of the mechanical parts can also be tested, and the specific method can be determined according to the structure of the mechanical parts.

[0108] In the above embodiments, there are various methods for obtaining the initial computational model. In some embodiments, a 3D scanner is used to scan the solid object of the mechanical part to obtain the initial computational model. This method can automatically model the mechanical part using a 3D scanner, and the modeling process is simple, but it has high requirements for hardware equipment. In other embodiments, 3D drawing software is used to model the mechanical part to obtain the initial computational model. This method can reduce the requirements for hardware equipment, thereby reducing costs.

[0109] This invention also provides a resistance testing device. Figure 8 A schematic diagram of a resistance testing device provided for implementing the present invention. (See diagram below.) Figure 8 As shown, the device includes:

[0110] The model acquisition module 810 is used to acquire the initial calculation model. The initial calculation model can perform electrical performance simulation of mechanical parts. The initial calculation model includes the part whose conductivity needs to be determined.

[0111] The measured value acquisition module 820 is used to acquire the measured resistance parameters of the mechanical part whose conductivity is to be determined when the probe of the ohmmeter is placed at preset positions on both sides of the part whose conductivity is to be determined.

[0112] The model optimization module 830 is used to perform simulation in the initial calculation model using the same measurement method as the actual measurement to obtain the simulated resistance parameters of the part of the mechanical component whose conductivity needs to be determined, and to adjust the material properties of the part of the mechanical component whose conductivity needs to be determined until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, so as to determine the optimized calculation model.

[0113] The resistance determination module 840 is used to perform electrical performance simulation on mechanical parts in the optimization calculation model to obtain the resistance value of the part of the mechanical parts whose conductivity needs to be determined.

[0114] The resistance testing device provided in this embodiment of the invention can execute the resistance testing method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0115] This invention also provides a resistance testing system. Figure 9 This is a schematic diagram of a resistance testing system provided in an embodiment of the present invention. Figure 9 As shown, the system includes: a ohmmeter 30 and a computer 10; the ohmmeter 30 is used to measure the measured resistance parameters of various parts of the mechanical component 20.

[0116] Figure 10 This is a schematic diagram of the structure of a computer provided for an embodiment of the present invention. The term "computer" is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0117] like Figure 10 As shown, the computer 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 and a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer programs stored in the ROM 12 or loaded into the RAM 13 from storage unit 18. The RAM 13 can also store various programs and data required for the operation of the computer 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0118] Multiple components in computer 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of monitors, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows computer 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0119] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as the resistance measurement method.

[0120] In some embodiments, the resistance measurement method may be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on computer 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the resistance measurement method described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to perform the resistance measurement method by any other suitable means (e.g., by means of firmware).

[0121] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0122] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0123] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0124] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for displaying information to the user (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor); and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0125] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0126] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0127] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0128] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for testing resistance, characterized in that, The method includes: An initial calculation model is obtained, which is capable of simulating the electrical performance of mechanical parts. The initial calculation model includes a part whose conductivity needs to be determined. The measured resistance parameters of the mechanical part whose conductivity needs to be determined are obtained by actually measuring the part with the probe of the ohmmeter placed at preset positions on both sides of the part with the conductivity to be determined. Using the same measurement method as the actual measurement, simulation is performed in the initial calculation model to obtain the simulated resistance parameters of the part of the mechanical component whose conductivity needs to be determined. The material properties of the part of the mechanical component whose conductivity needs to be determined are adjusted until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, so as to determine the optimized calculation model. The electrical performance of the mechanical component is simulated in the optimized calculation model to obtain the resistance value of the part of the mechanical component whose conductivity needs to be determined.

2. The resistance testing method according to claim 1, characterized in that, The conductivity of the mechanical component to be determined includes the welding area; The process of obtaining the measured resistance parameters of the mechanical component with undetermined conductivity obtained by placing the probe of the ohmmeter at preset positions on both sides of the portion with undetermined conductivity includes: The first and second sets of probes of the ohmmeter are placed on both sides of the welding area of ​​the mechanical part, and the measured resistance parameters including the welding area are obtained. In addition, in the step of determining the optimization calculation model, the material properties of the welding area are adjusted.

3. The resistance testing method according to claim 2, characterized in that, The mechanical component is a mechanical component of a battery cell; the mechanical component includes: a terminal post located at the top, a riveting block riveted to the outer edge of the top of the terminal post, an adapter plate located at the bottom, a first welding area located between the terminal post and the adapter plate, and a second welding area located at the bottom of the adapter plate; wherein, the first welding area and the second welding area are the parts of the mechanical component whose conductivity is yet to be determined; The step of placing the first and second sets of probes of the ohmmeter on both sides of the welding area of ​​the mechanical component, and actually measuring the measured resistance parameters including the welding area, includes: The first set of probes of the ohmmeter is placed on the top of the pole or the top of the riveting block, and the second set of probes of the ohmmeter is placed on the bottom of the adapter piece. The actual resistance parameters including the first welding area are obtained by actual measurement. And / or, place the first set of probes of the ohmmeter on the top of the pole or the top of the rivet block, and place the second set of probes of the ohmmeter on the bottom of the second welding area, and actually measure the measured resistance parameters including the first welding area and the second welding area.

4. The resistance testing method according to claim 3, characterized in that, The first welding area is a laser welding area or an ultrasonic welding area; And / or, the second welding area is a laser welding area or an ultrasonic welding area.

5. The method for testing resistance according to any one of claims 2-4, characterized in that, The mechanical component is a positive electrode mechanical component, the first set of probes is a positive electrode probe, and the second set of probes is a negative electrode probe; Alternatively, the mechanical component may be a negative electrode mechanical component, the first set of probes may be a negative electrode probe, and the second set of probes may be a positive electrode probe.

6. The resistance testing method according to claim 1, characterized in that, The process of obtaining the measured resistance parameters of the mechanical component with undetermined conductivity obtained by placing the probe of the ohmmeter at preset positions on both sides of the portion with undetermined conductivity includes: For the measurement of the same part of the mechanical component, the probe of the ohmmeter is placed at at least two preset positions, and at least two measured resistance parameters of the same part of the mechanical component are obtained by actual measurement.

7. The resistance testing method according to claim 6, characterized in that, The method employs the same measurement approach as actual measurements. Simulations are performed in the initial calculation model to obtain simulated resistance parameters for the portion of the mechanical component whose conductivity needs to be determined. The material properties of this portion are adjusted until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, thereby determining an optimized calculation model. This includes: For the measurement of the same part of the mechanical component, the same measurement method as the actual measurement is adopted. Simulation is performed in the initial calculation model to obtain the simulated resistance parameters of the same part of the mechanical component. The material properties of the same part of the mechanical component are adjusted until the difference between each simulated resistance parameter and the corresponding measured resistance parameter is less than the set threshold. The material properties obtained from each optimization are statistically calculated to obtain the optimal material properties, thereby determining the optimization calculation model.

8. The resistance testing method according to claim 1, characterized in that, The step of performing electrical performance simulation on the mechanical component in the optimized calculation model to obtain the resistance value of the portion of the mechanical component whose conductivity needs to be determined includes: In the optimized calculation model, the mechanical component is assigned an electric current and a ground plane; By extracting the electrical parameters of the portion of the mechanical component whose conductivity needs to be determined, the resistance value of that portion is obtained; the electrical parameters include: voltage, current density, and / or heat generation.

9. The resistance testing method according to claim 1, characterized in that, When performing electrical performance simulation on the mechanical component in the optimized calculation model to obtain the resistance value of the portion of the mechanical component whose conductivity needs to be determined, the method further includes: The individual resistance values ​​of each part of the mechanical component and / or the overall resistance value of the mechanical component are obtained.

10. The resistance testing method according to claim 1, characterized in that, The process of obtaining the initial computational model includes: The initial calculation model is obtained by scanning the physical object of the mechanical part using a 3D scanner. Alternatively, the mechanical part can be modeled using 3D drawing software to obtain the initial calculation model.

11. A resistance testing device, characterized in that, Mechanical components applied to battery cells; the device includes: The model acquisition module is used to acquire an initial calculation model, which is capable of simulating the electrical performance of the mechanical component. The initial calculation model includes a part whose conductivity needs to be determined. The measured value acquisition module is used to acquire the measured resistance parameters of the mechanical part whose conductivity is to be determined when the probe of the ohmmeter is placed at preset positions on both sides of the part whose conductivity is to be determined. The model optimization module is used to perform simulation in the initial calculation model using the same measurement method as the actual measurement to obtain the simulated resistance parameters of the part of the mechanical component whose conductivity needs to be determined, and to adjust the material properties of the part of the mechanical component whose conductivity needs to be determined until the difference between the simulated resistance parameters and the measured resistance parameters is less than a set threshold, so as to determine the optimized calculation model. The resistance determination module is used to perform electrical performance simulation on the mechanical component in the optimization calculation model to obtain the resistance value of the part of the mechanical component whose conductivity needs to be determined.

12. A resistance testing system, characterized in that, include: Oximeters and computers; The ohmmeter is used to measure the measured resistance parameters of each part of the mechanical component; The computer includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the resistance test method according to any one of claims 1-10.

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