A device and method for testing the single-side expansion thickness of a square aluminum shell battery

Abstract

The present invention relates to a device and a testing method for testing the single-sided expansion thickness of a square aluminum shell battery, and belongs to the technical field of new energy lithium batteries. It includes a base, on which a battery cell support structure is provided, and one side of the base is also provided with an upright column, and the upright column is rotatably connected to the base; the upright column is provided with an annular connecting piece, and one side of the connecting piece is connected to a rotating platform; the rotating platform is provided with a plurality of probe mounting grooves, each of which is provided with a probe body, and a probe cap is provided at the bottom of the probe body located at the center; the probe mounting groove is provided with a reading port, and a tightening switch is inserted and provided below the reading port. The present invention has a targeted design of a device and a testing method for testing the single-sided expansion thickness of a square aluminum shell battery, which can intuitively quantify the single-sided expansion thickness of the battery cell.

Description

Technical Field

[0001] The invention relates to a device and a method for testing the single-side expansion thickness of a square aluminum shell battery, belonging to the technical field of new energy lithium batteries. Background Art

[0002] Under the existing technology, square aluminum shell batteries generally use metal aluminum as the battery aluminum shell. Since aluminum is relatively soft, the battery thickness is very easy to change due to the increase of internal pressure during the charging and discharging process and due to gas production. In severe cases, it is very easy to cause swelling, which in turn affects the electrical performance and safety performance of the battery. Therefore, it is particularly important to control the thickness of the battery.

[0003] Currently, laboratories and mass production lines use manual calipers or pressure tests to measure battery thickness.

[0004] Manual caliper: Use a digital caliper to measure the battery thickness at the top, middle, bottom and surrounding areas of a single battery. Due to the limitation of the length of the caliper test end, only the thickness around the battery cell can be tested. The middle position cannot be measured, and the measurement operation is cumbersome. Since the caliper is a single-point measurement, the error is obvious and the data fluctuates greatly.

[0005] Pressure test: After applying a fixed pressure value on the battery surface, the battery thickness is obtained through height data feedback. This method applies a fixed pressure to the battery, resulting in obvious distortion of the battery thickness, and the actual thickness is much greater than the measured thickness. Moreover, the current measurement of battery thickness is to test the thickness of the entire battery, and there is no tool or method to test the thickness of a single-sided bulge of the battery.

[0006] The Chinese patent with the patent publication number CN113108742A discloses a solar cell silicon wafer size detection device, which belongs to the field of silicon wafer detection technology. It includes a base, a housing and a fixing plate, and also includes: a motor fixedly connected to the base; a rotating shaft fixedly connected to the output end of the motor; a workbench fixedly connected to the top of the rotating shaft; a cylinder fixedly connected to the workbench; a vacuum suction cup detachably connected to the output end of the cylinder; a placement seat fixedly connected to the base; and a discharge plate slidably connected to the placement seat.

[0007] The above patent controls the vacuum suction cups at both ends of the workbench to place the silicon wafer to be tested on the discharge board, and the cylinder and vacuum suction cup at the other end take out the tested silicon wafer, and detect the silicon wafer while loading and unloading, and the thickness of the silicon wafer at different positions can be measured, which greatly reduces the labor burden of the user and improves the measurement efficiency; however, placing the silicon wafer to be tested on the discharge board to measure the thickness of the battery obtains the thickness of the entire battery, and the square aluminum shell battery usually expands on both sides. The above application can only measure the overall thickness, but is not suitable for measuring the expanded thickness of a single side.

[0008] Therefore, in order to solve the above background problems, it is urgent to develop a device and a testing method for testing the single-side expansion thickness of square aluminum shell batteries. Summary of the invention

[0009] The purpose of the present invention is to solve the problems raised in the above background issues and to provide a device and a method for testing the single-sided expansion thickness of a square aluminum shell battery. The device and the method have a reasonable structure and can intuitively quantify the single-sided expansion thickness of the battery cell. The operation is simple, the human factor is small, and the data is reliable.

[0010] The object of the present invention is achieved as follows: A device for testing the single-side expansion thickness of a square aluminum shell battery comprises a base, a battery cell vacant support structure is arranged on the base, a vertical column is also arranged on one side of the base, and the vertical column is rotatably connected to the base;

[0011] The upright column is provided with an annular connecting piece, one side of which is connected to the rotating platform;

[0012] The rotating platform is provided with a plurality of probe installation slots, each of which is provided with a probe body, and a probe cap is provided at the bottom of the probe body located at the center;

[0013] The probe installation slot is provided with a reading port, and a tightening switch is inserted and arranged below the reading port.

[0014] The battery cell vacant support structure comprises a first support column, a second support column, a third support column and a fourth support column;

[0015] The first support column, the second support column, the third support column and the fourth support column are arranged at the four corners of the battery cell body, and rectangular grooves are arranged to match the battery cell body structure;

[0016] The bottoms of the first support column, the second support column, the third support column and the fourth support column are all provided with bottom brackets, and the bottom brackets are bottom boss structures, forming four-corner supports for the battery cell body.

[0017] The structure of the rotating platform matches the bottom surface structure of the base.

[0018] The probe body includes a measuring end and a reading end;

[0019] The measuring end and the reading end are both configured as cylindrical structures and are coaxially arranged;

[0020] The structural diameter of the reading end is larger than the structural diameter of the measuring end.

[0021] The probe mounting slots include four corner probe mounting slots and a central probe mounting slot;

[0022] The four-corner probe installation slots are distributed at the four corners of the rotating platform, matching the four corners of the battery body;

[0023] The central probe installation groove is arranged at the central position of the rotating platform and matches the central position of the battery cell body.

[0024] The height of the base is not less than 10 mm.

[0025] A method for testing the single-side expansion thickness of a square aluminum shell battery comprises the following steps:

[0026] Step 1: Calibrate the probe, make sure the probe scale value is 0 when the probe bottom in the four corner probe installation slots is flush with the base, and make sure the probe scale value is also 0 when the probe cap at the bottom of the probe in the center probe installation slot is flush with the base;

[0027] Step 2: Pull up the probes in the four corner probe installation slots and the center probe installation slot, tighten the tightening switch, and rotate the rotating platform through the vertical column to facilitate the entry of the battery cell;

[0028] Step 3: Place the battery cell body through the battery cell vacant support structure, and the battery cell body cooperates with the bottom bracket to form a vacant support through the first support column, the second support column, the third support column and the fourth support column;

[0029] Step 4: Rotate the rotating platform to the top of the battery body through the upright column, loosen the tightening switches on each probe installation slot in turn, lower the probe to the upper shell surface of the battery body, and tighten the tightening switch again after alignment;

[0030] Step 5: Read the probes in the four corner probe installation slots and take the average value as L1, and read the probe in the center probe installation slot as L2;

[0031] Step 6: The single-sided expansion thickness value of the cell body is obtained by the difference between the center probe reading L2 and the average value L1 of the four corner probe readings.

[0032] Compared with the prior art, the present invention has the following advantages:

[0033] The device and method for testing the single-side expansion thickness of a square aluminum shell battery of the present invention can intuitively quantify the single-side expansion thickness of the battery cell, and can evaluate the production process capability and the finished product qualification rate of the battery cell by evaluating the single-side expansion thickness, effectively evaluate the expansion pressure during the pack module, and control the thickness during assembly;

[0034] At the same time, the testing device of the present invention has reasonable structure, simple operation, small human influence factors and reliable data. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1The present invention is a schematic diagram of the overall structure of a device for testing the single-side expansion thickness of a square aluminum shell battery.

[0036] Figure 2 The present invention is a schematic diagram of a supporting structure of a device for testing the single-side expansion thickness of a square aluminum shell battery.

[0037] Figure 3 The present invention is a schematic diagram of a probe body of a device for testing the single-side expansion thickness of a square aluminum shell battery.

[0038] Among them: 1. Base; 2. Cell support structure; 3. Vertical column; 4. Connector; 5. Rotating platform; 6. Probe installation slot; 7. Reading port; 8. Tightening switch; 9. Probe body; 10. Probe cap; 11. Cell body;

[0039] 2.1, first support column; 2.2, second support column; 2.3, third support column; 2.4, fourth support column; 2.5, bottom bracket;

[0040] 9.1, measuring end; 9.2, reading end. DETAILED DESCRIPTION

[0041] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and several preferred specific embodiments, but the present invention is not limited to the following embodiments.

[0042] like Figures 1 to 3 As shown, the following device for testing the single-side expansion thickness of a square aluminum shell battery is used, which includes a base 1, on which a battery cell vacant support structure 2 is arranged, and a vertical column 3 is also arranged on one side of the base 1, and the vertical column 3 is rotatably connected to the base 1;

[0043] The upright column 3 is provided with an annular connecting member 4, one side of which is connected to the rotating platform 5;

[0044] The rotating platform 5 is provided with a plurality of probe installation slots 6, each of which is provided with a probe body 9, and a probe cap 10 is provided at the bottom of the probe body 9 located at the center;

[0045] The probe installation groove 6 is provided with a reading port 7 , and a tightening switch 8 is inserted and arranged below the reading port 7 .

[0046] The battery cell support structure 2 comprises a first support column 2.1, a second support column 2.2, a third support column 2.3 and a fourth support column 2.4;

[0047] The first support column 2.1, the second support column 2.2, the third support column 2.3 and the fourth support column 2.4 are arranged at the four corners of the battery cell body 11, and rectangular grooves are arranged to match the structure of the battery cell body 11;

[0048] The bottoms of the first support column 2.1, the second support column 2.2, the third support column 2.3 and the fourth support column 2.4 are all provided with a bottom bracket 2.5, and the bottom bracket 2.5 is a bottom boss structure, forming four corner supports for the battery cell body 11.

[0049] The structure of the rotating platform 5 matches the bottom surface structure of the base 1 .

[0050] The probe body 9 includes a measuring end 9.1 and a reading end 9.2;

[0051] The measuring end 9.1 and the reading end 9.2 are both configured as cylindrical structures and are coaxially arranged;

[0052] The structural diameter of the reading end 9.2 is greater than the structural diameter of the measuring end 9.1.

[0053] The probe mounting slot 6 includes four corner probe mounting slots and a central probe mounting slot;

[0054] The four-corner probe installation slots are distributed at the four corners of the rotating platform 5, matching the four corners of the battery body 11;

[0055] The central probe installation groove is arranged at the central position of the rotating platform 5 , matching the central position of the battery cell body 11 .

[0056] The height of the bottom bracket 2.5 is not less than 10 mm. Since the battery cell expands on both sides, it is necessary to ensure that the balance of the bottom is not affected by the expansion of the bottom.

[0057] Example 1

[0058] Using lithium iron phosphate battery (shell thickness 47.5mm, length 173mm, height 170mm): the battery state is 1C cycle 100% DOD charge and discharge after 3500 cycles, the battery swells.

[0059] In this embodiment, the following test method is used:

[0060] Step 1: Calibrate the probe, make sure the probe scale value is 0 when the probe bottom in the four corner probe installation slots is flush with the base 2.5, and make sure the probe scale value is also 0 when the probe cap 10 at the bottom of the probe in the center probe installation slot is flush with the base 2.5;

[0061] Step 2: Pull up the probes in the four corner probe installation slots and the center probe installation slot by 50 mm, tighten the tightening switch 8, and rotate the rotating platform 5 through the upright column 3 to facilitate the entry of the lithium iron phosphate battery;

[0062] Step 3: Place the battery cell body 11 through the battery cell vacant support structure 2, and the battery cell body 11 cooperates with the bottom bracket 2.5 through the first support column 2.1, the second support column 2.2, the third support column 2.3 and the fourth support column 2.4 to form a vacant support;

[0063] Step 4: Rotate the rotating platform 5 to the top of the battery body 11 through the upright column 3, loosen the tightening switch 8 on each probe installation groove 6 in turn, lower the probe to the upper shell surface of the battery body 11, and tighten the tightening switch 8 again after alignment;

[0064] Step 5: Record the probe readings in the four corner probe installation slots as A1, A2, A3 and A4 respectively, and take the average value as L1, and record the probe reading in the center probe installation slot as L2;

[0065] Step 6: The single-sided expansion thickness value of the cell body is obtained by the difference between the center probe reading L2 and the average value L1 of the four corner probe readings.

[0066] The test results are shown in Table 1.

[0067] Table 1. Single-sided measurement data of lithium iron phosphate battery

[0068]

[0069] Through analysis, it is known that the single-sided expansion thickness of the lithium iron phosphate battery is 2.3mm.

[0070] The above are only specific application examples of the present invention and do not constitute any limitation on the protection scope of the present invention. Any technical solution formed by equivalent transformation or equivalent replacement shall fall within the protection scope of the present invention.

Claims

1. A method for testing the single-side expansion thickness of a square aluminum shell battery, characterized in that: The testing method adopts a device for testing the single-side expansion thickness of a square aluminum shell battery, the device comprising a base (1), a battery cell vacant support structure (2) being arranged on the base (1), a vertical column (3) being arranged on one side of the base (1), and the vertical column (3) being rotatably connected to the base (1); The upright column (3) is provided with an annular connecting member (4), and the other side of the connecting member (4) is connected to the rotating platform (5); The rotating platform (5) is provided with a plurality of probe installation slots (6), each probe installation slot (6) is provided with a probe body (9), and a probe cap (10) is provided at the bottom of the probe body (9) located at the center; The probe mounting groove (6) is provided with a reading port (7), and a tightening switch (8) is inserted and arranged below the reading port (7); The battery cell vacant support structure (2) comprises a first support column (2.1), a second support column (2.2), a third support column (2.3) and a fourth support column (2.4); The first support column (2.1), the second support column (2.2), the third support column (2.3) and the fourth support column (2.4) are arranged at the four corners of the battery cell body (11), and rectangular grooves are arranged to match the structure of the battery cell body (11); The bottoms of the first support column (2.1), the second support column (2.2), the third support column (2.3) and the fourth support column (2.4) are all provided with bottom brackets (2.5), and the bottom brackets (2.5) are bottom boss structures, forming four-corner supports for the battery cell body (11); The test method comprises the following steps: Step 1: Calibrate the probe, ensuring that the probe scale value is 0 when the bottom of the probe in the four corner probe mounting slots is flush with the base (2.5), and the probe scale value is also 0 when the bottom of the probe cap (10) at the bottom of the probe in the center probe mounting slot is flush with the base (2.5); Step 2: Pull up the probes in the four corner probe installation slots and the center probe installation slot, tighten the tightening switch (8), and rotate the rotating platform (5) through the vertical column (3) to facilitate the entry of the battery cell; Step three: placing the battery cell body (11) through the battery cell aerial support structure (2), wherein the battery cell body (11) cooperates with the bottom bracket (2.5) through the first support column (2.1), the second support column (2.2), the third support column (2.3) and the fourth support column (2.4) to form aerial support; Step 4: Rotate the rotating platform (5) to the top of the battery body (11) through the upright column (3), loosen the tightening switch (8) on each probe installation groove (6) in turn, lower the probe to the upper shell surface of the battery body (11), and tighten the tightening switch (8) again after alignment; Step 5: Read the probes in the four corner probe installation slots and take the average value as L1, and read the probe in the center probe installation slot as L2; Step 6: The single-sided expansion thickness value of the cell body is obtained by the difference between the center probe reading L2 and the average value L1 of the four corner probe readings.

2. A method for testing the single-side expansion thickness of a square aluminum shell battery according to claim 1, characterized in that: The structure of the rotating platform (5) matches the bottom surface structure of the base (1).

3. A method for testing the single-side expansion thickness of a square aluminum shell battery according to claim 1, characterized in that: The probe body (9) comprises a measuring end (9.1) and a reading end (9.2); The measuring end (9.1) and the reading end (9.2) are both configured as cylindrical structures and are coaxially arranged; The structural diameter of the reading end (9.2) is larger than the structural diameter of the measuring end (9.1).

4. A method for testing the single-side expansion thickness of a square aluminum shell battery according to claim 1, characterized in that: The probe mounting groove (6) comprises four corner probe mounting grooves and a central probe mounting groove; The four-corner probe mounting grooves are distributed at the four corners of the rotating platform (5) and match the four corner positions of the battery cell body (11); The central probe installation groove is arranged at the central position of the rotating platform (5) and matches the central position of the battery cell body (11).

5. A method for testing the single-side expansion thickness of a square aluminum shell battery according to claim 1, characterized in that: The height of the base (2.5) is not less than 10 mm.

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