An accuracy measuring device and method for probe-type fixture line measurement accuracy

Abstract

This invention provides an accuracy measurement device and method for probe-type fixture wire measurement in the field of lithium battery testing technology. The device includes: an upper PCB board with two first positioning holes and two comb-shaped openings; an insulating layer surrounding each comb-shaped opening; a first wiring layer surrounding each insulating layer, with each first positioning hole located within the first wiring layer; a lower PCB board with two second positioning holes and a through hole, and a second wiring layer on its top surface; the second positioning holes are positioned to match the first positioning holes; the shape of the second wiring layer matches the two comb-shaped openings, and the through hole is located in the middle of the second wiring layer; two conductive nuts are respectively located below each of the second positioning holes; and two conductive screws, from top to bottom, pass through the first positioning holes and the second positioning holes and are threadedly connected to the conductive nuts. The advantage of this invention is that it enables the measurement of the influence of induced magnetic fields introduced by different closed interval areas, thereby ensuring measurement accuracy.

Description

Technical Field

[0001] This invention relates to the field of lithium battery testing technology, and in particular to an accuracy measuring device and method for probe-type fixture line measurement accuracy. Background Technology

[0002] With the rapid development of lithium battery technology, the energy density of lithium batteries is increasing. In different usage environments, the voltage of lithium batteries also varies, and the effective utilization rate of lithium battery energy is a very important parameter.

[0003] The magnitude of AC internal resistance directly determines the energy loss of a lithium battery during energy release, making AC internal resistance testing a crucial test. Aging and manufacturing defects in lithium batteries lead to performance degradation and irreversible changes in their chemical composition. The impedance of a lithium battery increases linearly with decreasing capacity. Impedance can determine battery capacity and whether replacement is necessary, thereby reducing maintenance costs.

[0004] Therefore, the accuracy of measurement is crucial in the AC internal resistance testing of lithium batteries. AC internal resistance is tested using a four-wire system, which separates the AC disturbance current signal line from the corresponding disturbance voltage sampling signal line to eliminate the influence of wiring. Although a four-wire wiring method is used, the closed area formed by the test fixture wires differs when measuring different lithium batteries. The influence of the induced magnetic field introduced by different closed area areas varies. The induced magnetic field is mainly caused by the magnetic flux generated by the disturbance source current, the magnetic flux generated by eddy currents, and external magnetic flux, thus affecting the measurement differently. Traditionally, there has been no measurement of the influence of different closed area areas of the test fixture wires on the measured values ​​of the test equipment when connecting different lithium batteries.

[0005] Therefore, how to provide an accuracy measurement device and method for probe-type fixture line measurement, so as to measure the influence of the induced magnetic field introduced by different closed interval areas and thus ensure measurement accuracy, has become an urgent technical problem to be solved. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide an accuracy measuring device and method for probe-type fixture line measurement, which realizes the measurement of the influence of induced magnetic field introduced by different closed interval areas, thereby ensuring measurement accuracy.

[0007] In a first aspect, the present invention provides an accuracy measuring device for probe-type fixture line measurement accuracy, comprising:

[0008] A PCB board is provided with two first positioning holes and two comb-shaped openings symmetrically arranged; an insulating layer is provided around each of the comb-shaped openings; a first trace layer is provided around each insulating layer on the top surface of the PCB board, and each of the first positioning holes is located in a first trace layer.

[0009] A bottom PCB board has two symmetrical second positioning holes, a via in the middle, a second routing layer on the top surface, and a third routing layer on the bottom surface; the second positioning holes are matched with the positions of the first positioning holes; the shape of the second routing layer matches the two comb-shaped openings, and the via is located in the middle of the second routing layer;

[0010] Two conductive nuts are respectively located below one of the second positioning holes;

[0011] Two conductive screws pass through the first positioning hole and the second positioning hole from top to bottom and are threadedly connected to a conductive nut.

[0012] Furthermore, the third routing layer is rectangular, and the second positioning hole and via are located within the third routing layer.

[0013] Furthermore, it also includes:

[0014] A four-wire clamp cable is provided with two plugs, a positive probe and a negative probe;

[0015] Both the positive and negative probes include:

[0016] A single disturbance voltage sampling line;

[0017] A ring-shaped insulating layer surrounds the disturbance voltage sampling line;

[0018] A disturbance current output line is wrapped around the annular insulating layer.

[0019] Secondly, the present invention provides an accuracy measurement method for probe-type fixture line measurement accuracy, comprising the following steps:

[0020] Step S1: Place the upper PCB board on top of the lower PCB board, and attach the PCB board and the lower PCB board by means of conductive nuts, conductive screws, first positioning holes and second positioning holes, so that the comb-shaped openings coincide with the position of the second trace layer.

[0021] Step S2: Connect the disturbance voltage sampling line to the second trace layer through a via, and connect the disturbance current output line to the first trace layer, so that the disturbance current output by the disturbance current output line passes through the first trace layer, screw, and nut on one side in sequence to the third trace layer, and then passes through the nut and screw on the other side to the first trace layer.

[0022] Step S3: Insert the positive and negative probes of the AC internal resistance tester into the symmetrical positions of the two comb-shaped openings to measure the AC internal resistance.

[0023] Step S4: Adjust the positions of the positive and negative probes inserted into the comb-shaped opening to change the area of ​​the closed interval, continue to measure the AC internal resistance, and record the AC internal resistance measured under different closed interval areas.

[0024] The advantages of this invention are:

[0025] By setting a first positioning hole, a comb-shaped opening, an insulating layer, and a first trace layer on the upper PCB board, and setting a second positioning hole, a via, a second trace layer, and a third trace layer on the lower PCB board; the first and third trace layers are connected by conductive nuts and conductive screws, and the second trace layer is isolated from the first trace layer by an insulating layer. The shape of the second trace layer matches the comb-shaped opening. By adjusting the positions of the positive and negative probes inserted into the comb-shaped opening, the area of ​​the closed interval can be changed. The insulating layer can avoid the possibility of contact between the disturbance current test part and the disturbance voltage test part during the test. The single-point connection method through the via avoids the disturbance current flowing through the disturbance voltage acquisition loop, ensuring that only the area of ​​the closed interval exists as a single variable. Finally, the influence of the induced magnetic field introduced by different closed interval areas can be measured, thereby ensuring measurement accuracy. Attached Figure Description

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0027] Figure 1 This is a top view of the PCB board of this invention.

[0028] Figure 2 This is a bottom view of the PCB board of this invention.

[0029] Figure 3 This is a top view of the PCB board according to the present invention.

[0030] Figure 4 This is a bottom view of the PCB board according to the present invention.

[0031] Figure 5 This is a schematic diagram of the structure of the four-wire clamping wire of the present invention.

[0032] Figure 6 This is a schematic diagram of the structure of the positive electrode probe and the negative electrode probe of the present invention.

[0033] Figure 7 This is a flowchart of an accuracy measurement method for a probe-type fixture line measurement accuracy according to the present invention.

[0034] Marker explanation:

[0035] 1-Upper PCB board, 2-Lower PCB board, 3-Four-wire clamping line, 11-First positioning hole, 12-Comb-shaped opening, 13-Insulating layer, 14-First routing layer, 21-Second positioning hole, 22-Through hole, 23-Second routing layer, 24-Third routing layer, 31-Plug, 32-Positive probe, 33-Negative probe, 321-Disturbance voltage sampling line, 322-Annular insulating layer, 323-Disturbance current output line. Detailed Implementation

[0036] Please refer to Figures 1 to 7 As shown, a preferred embodiment of the accuracy measuring device for probe-type fixture line measurement of the present invention includes:

[0037] A PCB board 1 has two first positioning holes 11 symmetrically arranged and two comb-shaped openings 12 symmetrically arranged; an insulating layer 13 is arranged around each of the comb-shaped openings 12; a first wiring layer 14 is arranged around each insulating layer 13 on the top surface of the PCB board 1, and each of the first positioning holes 11 is located in a first wiring layer 14; there are no electrical wirings on the bottom surface of the PCB board 1.

[0038] A lower PCB board 2 is symmetrically provided with two second positioning holes 21, a via 22 in the middle, a second routing layer 23 on the top surface, and a third routing layer 24 on the bottom surface; the second positioning holes 21 are matched with the positions of the first positioning holes 11; the shape of the second routing layer 23 is matched with the two comb-shaped openings 12, and the via 22 is located in the middle of the second routing layer 23;

[0039] Two conductive nuts (not shown) are respectively located below one of the second positioning holes 11;

[0040] Two conductive screws (not shown) pass through the first positioning hole 11 and the second positioning hole 21 from top to bottom and are threadedly connected to a conductive nut.

[0041] The third wiring layer 24 is rectangular, and the second positioning hole 21 and the via 22 are located within the third wiring layer 24.

[0042] Also includes:

[0043] A four-wire clamp wire 3 is provided with two plugs 31, a positive probe 32 and a negative probe 33;

[0044] Both the positive electrode probe 32 and the negative electrode probe 33 include:

[0045] A disturbance voltage sampling line 321 can retract when subjected to external pressure;

[0046] A ring-shaped insulating layer 322 surrounds the disturbance voltage sampling line 321;

[0047] A disturbance current output line 323 surrounds the annular insulating layer 322.

[0048] A preferred embodiment of the accuracy measurement method for probe-type fixture line measurement of the present invention includes the following steps:

[0049] Step S1: Place the upper PCB board on top of the lower PCB board, and attach the PCB board and the lower PCB board by means of conductive nuts, conductive screws, first positioning holes and second positioning holes, so that the comb-shaped openings coincide with the position of the second trace layer; since there are no electrical wirings on the bottom surface of the upper PCB board, it can be placed on top of the lower PCB board.

[0050] Step S2: Connect the disturbance voltage sampling line to the second trace layer through a via, and connect the disturbance current output line to the first trace layer, so that the disturbance current output by the disturbance current output line passes through the first trace layer, screw, and nut on one side in sequence to the third trace layer, and then passes through the nut and screw on the other side to the first trace layer.

[0051] Step S3: Insert the positive and negative probes of the AC internal resistance tester into the symmetrical positions of the two comb-shaped openings to measure the AC internal resistance.

[0052] Step S4: Adjust the positions of the positive and negative probes inserted into the comb-shaped opening to change the area of ​​the closed interval, continue to measure the AC internal resistance, and record the AC internal resistance measured under different closed interval areas.

[0053] During the measurement process, the AC disturbance current output signal of the AC internal resistance test equipment and the disturbance voltage sampling signal are connected at a single point through a via in the entire electrical flow circuit. The disturbance current does not flow through the sampling circuit of the disturbance voltage. Therefore, during the entire test process, the influence of the different closed interval areas formed by the four-wire fixture wires used in the measurement process on the test accuracy can be reliably obtained. This allows for the determination of the degree of influence of the different closed interval areas of the four-wire fixture wires on the test signal when testing the AC internal resistance of different packaged lithium batteries.

[0054] In summary, the advantages of this invention are as follows:

[0055] By setting a first positioning hole, a comb-shaped opening, an insulating layer, and a first trace layer on the upper PCB board, and setting a second positioning hole, a via, a second trace layer, and a third trace layer on the lower PCB board; the first and third trace layers are connected by conductive nuts and conductive screws, and the second trace layer is isolated from the first trace layer by an insulating layer. The shape of the second trace layer matches the comb-shaped opening. By adjusting the positions of the positive and negative probes inserted into the comb-shaped opening, the area of ​​the closed interval can be changed. The insulating layer can avoid the possibility of contact between the disturbance current test part and the disturbance voltage test part during the test. The single-point connection method through the via avoids the disturbance current flowing through the disturbance voltage acquisition loop, ensuring that only the area of ​​the closed interval exists as a single variable. Finally, the influence of the induced magnetic field introduced by different closed interval areas can be measured, thereby ensuring measurement accuracy.

[0056] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An accuracy measuring device for probe-type fixture line measurement, characterized in that: include: A PCB board is provided with two first positioning holes and two comb-shaped openings symmetrically arranged; an insulating layer is provided around each of the comb-shaped openings; a first trace layer is provided around each insulating layer on the top surface of the PCB board, and each of the first positioning holes is located in a first trace layer. A bottom PCB board has two symmetrical second positioning holes, a via in the middle, a second routing layer on the top surface, and a third routing layer on the bottom surface; the second positioning holes are matched with the first positioning holes; the shape of the second routing layer matches the two comb-shaped openings, and the via is located in the middle of the second routing layer; the third routing layer is rectangular, and the second positioning holes and the via are located inside the third routing layer; Two conductive nuts are respectively located below one of the second positioning holes; Two conductive screws pass through the first positioning hole and the second positioning hole from top to bottom and are threadedly connected to a conductive nut. A four-wire clamp cable is provided with two plugs, a positive probe and a negative probe; Both the positive and negative electrode probes include: A single disturbance voltage sampling line; A ring-shaped insulating layer surrounds the disturbance voltage sampling line; A disturbance current output line is wrapped around the annular insulating layer.

2. A method for measuring the accuracy of a probe-type fixture line measurement, characterized in that: The method requires the use of the measuring device as described in claim 1 and includes the following steps: Step S1: Place the upper PCB board on top of the lower PCB board, and attach the PCB board and the lower PCB board by means of conductive nuts, conductive screws, first positioning holes and second positioning holes, so that the comb-shaped openings coincide with the position of the second trace layer. Step S2: Connect the disturbance voltage sampling line to the second trace layer through a via, and connect the disturbance current output line to the first trace layer, so that the disturbance current output by the disturbance current output line passes through the first trace layer, screw, and nut on one side in sequence to the third trace layer, and then passes through the nut and screw on the other side to the first trace layer. Step S3: Insert the positive and negative probes of the AC internal resistance tester into the symmetrical positions of the two comb-shaped openings to measure the AC internal resistance. Step S4: Adjust the positions of the positive and negative probes inserted into the comb-shaped opening to change the area of ​​the closed interval, continue to measure the AC internal resistance, and record the AC internal resistance measured under different closed interval areas.

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