Air tightness detection device and battery production system

Abstract

The utility model relates to an air tightness detection device and a battery production system. The air tightness detection device comprises a pressing tool, a first sealing gasket and a second sealing gasket. The pressing tool comprises a clamping space which is used for clamping a to-be-tested piece and is adjustable in space size in the first direction, and an inflation part which is used for being in butt joint with an inflation hole of the to-be-tested piece located in the clamping space. The pressing tool further comprises an exhaust part and an installation space, and the installation space is arranged between the exhaust part and the clamping space in a communicating mode in the first direction. One of the first sealing gasket and the second sealing gasket is arranged in the installation space and abuts against the detected end of the to-be-detected piece, and the second sealing gasket is provided with an avoiding hole. Wherein the first sealing gasket arranged in the mounting space can seal the second welding mark and avoid the first welding mark, and the avoiding hole of the second sealing gasket arranged in the mounting space can cover the second welding mark and is communicated with the exhaust part. The air tightness detection device is helpful for improving the production efficiency of a battery production system.

Description

Technical Field

[0001] The present application relates to the technical field of battery preparation, and in particular to an airtightness detection device and a battery production system. Background Art

[0002] In the production process of battery cells, the sealing installation of the cover plate, sealing pins and other parts on the shell is mostly achieved by laser welding. If the welding quality is not up to standard, the welding position is prone to leakage, which is not conducive to the sealing and reliability of the battery cell. Therefore, before mass assembly of battery cells, the first assembly is usually tested for airtightness.

[0003] The conventional manual air tightness testing method is time-consuming and labor-intensive, with low production efficiency and low detection reliability. Utility Model Content

[0004] Based on this, it is necessary to provide an airtightness detection device and a battery production system to address the problems of low detection reliability and reduced production efficiency of battery cell airtightness detection.

[0005] In a first aspect, an embodiment of the present application provides an airtightness detection device for detecting the airtightness of a test piece having an air filling hole, wherein a test end of the test piece in a first direction has a first weld mark and a second weld mark, wherein the first weld mark is located at an edge of the test end, and the second weld mark is located in the middle of the test end, and the airtightness detection device comprises:

[0006] A clamping tool, comprising a clamping space for clamping the test piece and having an adjustable spatial size in the first direction, and an inflation portion for docking with an inflation hole of the test piece located in the clamping space, the clamping tool also comprising an exhaust portion and an installation space, the installation space being arranged in communication between the exhaust portion and the clamping space in the first direction;

[0007] A first sealing pad and a second sealing pad, one of which is arranged in the installation space and abuts against the tested end of the test piece, and the second sealing pad has an avoidance hole;

[0008] The first sealing gasket arranged in the installation space can seal the second welding mark and avoid the first welding mark; the second sealing gasket arranged in the installation space, the avoidance hole thereof can cover the second welding mark and connect to the exhaust part.

[0009] In some embodiments, the pressing tool is provided with a first sink opening toward the clamping space, the exhaust portion is connected to the first sink, and the installation space includes the inner space of the first sink;

[0010] The first sealing pad and the second sealing pad can be selectively disposed in the first recessed groove, and can partially extend out of the first recessed groove to abut against the tested end of the test piece.

[0011] In some embodiments, the first sealing pad has a first sealing surface for abutting the inspected end;

[0012] The first sealing surface is configured such that: on the tested end of the test piece located in the clamping space, the first welding mark is located at the periphery of the orthographic projection of the first sealing surface.

[0013] In some embodiments, the second sealing pad has a second sealing surface for abutting the inspected end, and the outer contour dimension of the second sealing surface is the same as the outer contour dimension of the first sealing surface.

[0014] In some embodiments, the second sealing gasket disposed in the installation space is capable of sealing the first welding mark.

[0015] In some embodiments, the inflation portion is located on one side of the pressing fixture in the first direction and is open toward the clamping space so as to dock with the inflation hole of the test piece located in the clamping space in the first direction.

[0016] In some embodiments, the inflation portion includes an inflation cavity and an inflation air path connected to the inflation cavity, the clamping space is located between the inflation cavity and the exhaust portion in the first direction, and the inflation cavity is open toward the clamping space.

[0017] In some embodiments, the air tightness detection device also includes a third sealing gasket, which is arranged at the open end of the inflation cavity and is used to seal the test piece; the third sealing gasket is provided with an air hole for avoiding the inflation hole and connecting the inflation cavity.

[0018] In some embodiments, a second groove is disposed at the open end of the inflation cavity, and the third sealing gasket is disposed in the second groove and partially extends out of the second groove.

[0019] In some embodiments, the clamping tool comprises a first clamping portion, a second clamping portion and a connecting portion, the first clamping portion and the second clamping portion are spaced apart from each other in the first direction by the clamping space, the connecting portion connects the first clamping portion and the second clamping portion, and supports the first clamping portion and the second clamping portion to move relative to each other along the first direction;

[0020] The exhaust portion is arranged on the first pressing portion, and the inflation portion is arranged on the second pressing portion.

[0021] In some embodiments, the connecting portion includes a connecting column and a clamping nut, one end of the connecting column is fixedly connected to the second clamping portion, the other end of the connecting column is provided with an external threaded portion, the first clamping portion is movably sleeved on the connecting column, the clamping nut is threadably connected to the external threaded portion, and is located on the side of the first clamping portion away from the second clamping portion.

[0022] In a first aspect, an embodiment of the present application provides a battery production system, comprising an airtightness detection device as described in any of the above embodiments.

[0023] In some embodiments, the airtightness detection device is used for a cylindrical battery cell shell welded part, the cylindrical battery cell shell welded part comprises a shell and a cover, the cover is welded to one side of the shell in the first direction, a sealing nail is welded on the cover, the welding mark position of the cover is used as the first welding mark, and the welding mark position of the sealing nail is used as the second welding mark;

[0024] A pole is disposed on the other side of the shell in the first direction, and the charging hole is disposed on the pole.

[0025] In actual application, the air tightness detection device and battery production system mentioned above only need to clamp the test piece in the clamping space, and use the inflation part on the clamping tool to align with the inflation hole on the test piece, without manual gluing, to achieve inflation into the test piece, which not only saves time and effort, but also makes the detection more reliable. Moreover, by selecting and using the first sealing gasket and the second sealing gasket, the specific cause of the leakage can be quickly determined in the event of leakage, which is convenient for subsequent production to make processing adjustments based on the specific cause of the leakage, and helps to improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0027] Figure 1 Schematic diagram of the usage status of the airtightness detection device in some embodiments.

[0028] Figure 2 for Figure 1 The exploded view of the airtightness detection device shown is in a state of using the first sealing gasket.

[0029] Figure 3 for Figure 1 The internal schematic diagram of the airtightness detection device shown is in the state of using the first sealing gasket.

[0030] Figure 4 for Figure 1 The exploded view of the airtightness detection device shown is in a state of using a second sealing gasket.

[0031] Figure 5 for Figure 1 The internal schematic diagram of the airtightness detection device shown is in the state of using the second sealing gasket.

[0032] Figure 6 for Figure 5 Enlarged view of point I in the middle.

[0033] Figure 7 for Figure 5 Enlarged view of point II in the middle.

[0034] The reference numerals in the specific implementation manner are as follows:

[0035] 100, air tightness detection device; 10, clamping tool; X, first direction; R, clamping space; 11, first clamping part; 11a, exhaust part; 11b, first sink; 12, second clamping part; 12c, inflation part; c1, inflation cavity; c2, inflation air path; 12d, second sink; 13, connecting part; 13e, connecting column; 13f, external threaded part; 13g, clamping nut; 20, first sealing gasket; 21, first sealing surface; 30, second sealing gasket; 31, second sealing surface; k1, avoidance hole; 40, third sealing gasket; k2, air hole; 50, bottom plate; 200, test piece; J, test end; S1, first weld mark; S2, second weld mark; q, inflation hole; 200A, cylindrical shell of battery cell to be tested; A1, cover; A2, sealing nail; A3, pole. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0037] In the description of the present application, it should be understood that terms such as “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships, if any, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0038] In addition, if present, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0039] In this application, unless otherwise clearly specified and limited, if any, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0040] In the present application, if it appears, unless otherwise clearly specified and limited, a first feature “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature “above”, “above” and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature “below”, “below” and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0041] It should be noted that, if present, when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0042] During the conventional manual air tightness test, it is usually necessary to manually glue the inflation interface to the punched position after drilling a hole in the welded shell, which is time-consuming and labor-intensive, and when the pressure is too high, it is easy to burst the gluing position, resulting in inaccurate test results. In addition, during the conventional test, if the air tightness test fails, it is impossible to effectively determine whether the leakage is caused by poor welding of the cover plate or poor welding of the sealing pins. Other means must be taken to determine the specific cause, lengthening the test process and reducing production efficiency. Based on this, the embodiments of the present application provide an air tightness test device and a battery production system that can improve the detection reliability of battery cell air tightness testing and improve production efficiency.

[0043] In the embodiment of the present application, the airtightness detection device can be applied to, but not limited to, the airtightness detection of the welding parts of the battery shell, and can also be applied to the airtightness detection of the welding shell of other products. In the embodiment of the present application, the airtightness detection device is used to detect the airtightness of the test piece with an air filling hole, and the test end of the test piece in the first direction has a first weld mark and / or a second weld mark, the first weld mark is located at the edge of the test end, and the second weld mark is located in the middle of the test end.

[0044] In some application examples, the part to be tested is a cell shell weldment, which is a cell outer frame structure obtained by welding the shell of the cell shell to the cover plate and welding a sealing pin at the injection hole of the cover plate. The cell shell weldment is convenient for the first piece inspection of the airtightness of the cover plate welding position and the sealing pin welding position to determine the accurate welding parameters. The inside of the shell is usually empty, and no electrolyte, electrode assembly, etc. are set.

[0045] In actual use, the first direction may be, but is not limited to, the height direction of the cell shell welded part, and the inspected end in the height direction may be the bottom or top of the cell shell welded part. Usually, the inspected end of the cell shell welded part has a first weld mark and a second weld mark, the first weld mark corresponds to the welding position between the shell and the cover plate, and the second weld mark corresponds to the welding position between the injection hole on the cover plate and the sealing pin. Usually, but not limited to, the first weld mark and the second weld mark are annular weld marks.

[0046] The battery production system in the embodiment of the present application uses the airtightness detection device proposed in the embodiment of the present application to perform airtightness detection on the welding position of the battery cell shell welding part. The test piece adapted by the airtightness detection device can be a cylindrical battery cell shell, a square battery cell shell, etc., to perform airtightness detection on at least one first piece in the battery cell assembly process, mainly but not limited to detecting the airtightness of the welding position between the cover plate and the shell, and the welding position between the sealing pin and the cover plate.

[0047] The airtightness detection device is introduced in detail below.

[0048] According to some embodiments of the present application, referring to Figures 1 to 5 The airtightness detection device 100 provided in the embodiment of the present application includes a clamping tool 10, a first sealing gasket 20 and a second sealing gasket 30. The clamping tool 10 includes a clamping space R for clamping the test piece 200 and having an adjustable space size in the first direction X, and an inflatable portion 12c for docking with the inflatable hole q of the test piece 200 located in the clamping space R. The clamping tool 10 also includes an exhaust portion 11a and an installation space, and the installation space is connected and arranged between the exhaust portion 11a and the clamping space R in the first direction X. Either the first sealing gasket 20 or the second sealing gasket 30 is arranged in the installation space and abuts against the inspected end J of the test piece 200, and the second sealing gasket 30 has an avoidance hole k1. Among them, the first sealing gasket 20 arranged in the installation space can seal the second weld mark S2 and avoid the first weld mark S1, and the second sealing gasket 30 arranged in the installation space has an avoidance hole k1 that can cover the second weld mark S2 and connect to the exhaust portion 11a.

[0049] The clamping tool 10 is the main structure of the air tightness testing device 100, and is used to clamp the test piece 200 in the clamping space R. In order to facilitate the placement of the test piece 200, the size of the clamping space R in the first direction X is adjustable. Regarding the specific structure of the clamping tool 10, those skilled in the art can obtain it through conventional design, and the present application will illustrate the structure of the clamping tool 10 in the following embodiments.

[0050] The clamping tool 10 also has an inflating portion 12c, which is used to dock with the inflating hole q on the test piece 200 when the clamping tool 10 clamps the test piece 200, so as to inflate the inflating hole q. The inflating portion 12c can be connected to the inflating hole q, an inflating joint, etc.

[0051] The pressing tool 10 is provided with an exhaust portion 11a and an installation space. The exhaust portion 11a may be an exhaust cavity, an exhaust hole, etc. When the airtightness detection device 100 is in a non-working state, the exhaust portion 11a, the installation space, and the clamping space R are spatially connected in sequence. It should be noted that the installation space may be formed by an installation hole or an installation groove independent of the clamping space R, or may be an integral space with the clamping space R.

[0052] The installation space is used to selectively install the first sealing gasket 20 and the second sealing gasket 30. The first sealing gasket 20 and the second sealing gasket 30 are usually made of sealing materials such as rubber and silicone, and the materials can be selected by those skilled in the art in conventional manner.

[0053] The first sealing gasket 20 may be a solid plate-shaped / block-shaped structure, so that when it is arranged in the installation space, it can seal the second weld mark S2 on the test piece 200. Of course, other hole structures that avoid the second weld mark S2 can also be provided on the first sealing gasket 20, as long as it can seal the second weld mark S2 so that there is no air leakage even if the air tightness at the second weld mark S2 is not good.

[0054] When the first sealing gasket 20 is arranged in the installation space, the first sealing gasket 20 avoids the first weld mark S1, that is, the first sealing gasket 20 does not seal the first weld mark S1. Specifically, the first sealing gasket 20 has a smaller outline size and can only cover the second weld mark S2 but not the first weld mark S1, so that the first weld mark S1 is exposed in the clamping space R. Specifically, a ventilation groove is provided on the first sealing gasket 20, and the ventilation groove can cover the first weld mark S1 and communicate with the atmosphere, that is, the gas leaked from the first weld mark S1 can be discharged from the ventilation groove. A person skilled in the art can make a conventional design regarding the structure of the ventilation groove.

[0055] When the second sealing gasket 30 is arranged in the installation space, the avoidance hole k1 of the second sealing gasket 30 can cover the second weld mark S2, that is, the existence of the avoidance hole k1 allows the second sealing gasket 30 to avoid the second weld mark S2 without sealing the second weld mark S2. The formation of the avoidance hole k1 can be specifically designed according to the shape of the second weld mark S2. For example, if the second weld mark S2 is annular, the avoidance hole k1 can be an annular hole, a cylindrical hole, etc. The avoidance hole k1 is connected to the exhaust part 11a, so that the gas leaked from the second weld mark S2 can be discharged from the avoidance hole k1 to the exhaust part 11a.

[0056] Taking the test piece 200 as a battery cell housing welded part as an example, the air tightness test process is introduced. The test process is roughly as follows:

[0057] The first step is to increase the size of the clamping space R in the first direction X, place the battery cell housing weldment in the clamping space R, and set its inspected end J toward the exhaust part 11a, and the inflation part 12c is connected to its inflation hole q;

[0058] The second step is to install the first sealing gasket 20 in the installation space so that the first sealing gasket 20 abuts against the inspected end J of the cell housing weldment. At this time, the first sealing gasket 20 seals the second welding mark S2 (welding position of the sealing nail A2) on the inspected end J and avoids the first welding mark S1 (welding position of the cover A1); or, install the second sealing gasket 30 in the installation space so that the second sealing gasket 30 abuts against the inspected end J of the cell housing weldment. At this time, the avoidance hole k1 of the second sealing gasket 30 allows the second welding mark S2 on the inspected end J to leak;

[0059] The third step is to adjust the size of the clamping space R so that the clamping tool 10 clamps the battery cell housing weldment; then, the inflation hole q on the battery cell housing weldment is inflated to a certain positive pressure through the inflation part 12c, and then the inflation is stopped;

[0060] The fourth step is to monitor the changes in the air pressure inside the battery shell weldment. If the air pressure decreases, when the first sealing gasket 20 is installed in the installation space, it means that there is a leak at the first welding mark S1 position (i.e., the cover A1 position), that is, the cause of the leak is poor welding of the cover A1. If the second sealing gasket 30 is installed in the installation space, it means that there is a leak at the second welding mark S2 position (i.e., the sealing nail A2 position), that is, the cause of the leak is poor welding of the sealing nail A2. If the air pressure change is within a reasonable range, it means that there is no leak and the test has passed.

[0061] Thus, in actual application, the above-mentioned air tightness detection device only needs to clamp the test piece 200 in the clamping space R, and use the inflation part 12c on the pressing tool 10 to align with the inflation hole q on the test piece 200, and no manual gluing is required to achieve inflation into the test piece 200, which not only saves time and effort, but also makes the detection more reliable. Moreover, through the selection and use of the first sealing gasket 20 and the second sealing gasket 30, the specific cause of the leakage can be quickly determined in the event of leakage, which is convenient for subsequent production to make processing adjustments based on the specific cause of the leakage, and helps to improve production efficiency.

[0062] In some embodiments, reference Figure 3 and Figure 5 The clamping tool 10 is provided with a first recessed groove 11b open to the clamping space R, the exhaust portion 11a is connected to the first recessed groove 11b, and the installation space includes the inner space of the first recessed groove 11b. The first sealing gasket 20 and the second sealing gasket 30 can be selectively arranged in the first recessed groove 11b, and can partially extend out of the first recessed groove 11b to abut against the inspected end J of the inspected piece 200.

[0063] The first recessed groove 11 b is a groove structure open toward the clamping space R, and the first sealing gasket 20 and the second sealing gasket 30 are installed in the first recessed groove 11 b. The first recessed groove 11 b can realize the rapid installation and positioning of the first sealing gasket 20 and the second sealing gasket 30.

[0064] When either the first sealing gasket 20 or the second sealing gasket 30 is installed in the first recess 11b, parts of the first sealing gasket 20 and the second sealing gasket 30 can extend out of the first recess 11b and abut against the tested end J of the test piece 200 to effectively seal the relevant parts of the tested end J.

[0065] Specifically, the first sink groove 11 b may be a circular groove, a square groove, a conical groove, etc. The specific contour shape remains unchanged as long as the first sealing gasket 20 and the second sealing gasket 30 can be installed and positioned.

[0066] It should be noted that, when the outer contour dimensions of the first gasket 20 and the second gasket 30 are the same, the first sink groove 11b can be a straight groove whose cross-sectional dimensions remain unchanged along the groove depth direction. If the outer contour dimensions of the first gasket 20 and the second gasket 30 are different, the first sink groove 11b can be a stepped groove whose cross-sectional dimensions change gradually. Of course, if the first gasket 20 and the second gasket 30 can also have partially the same outer contour dimensions and partially different outer contour dimensions, and the portions with the same outer contour dimensions are assembled with the first sink groove 11b which is a straight groove. The specific structure of the first sink groove 11b can be adaptively designed according to the specific structures of the first gasket 20 and the second gasket 30.

[0067] In some embodiments, reference Figure 3 The first sealing gasket 20 has a first sealing surface 21 for abutting the tested end J. The first sealing surface 21 is configured as follows: on the tested end J of the test piece 200 located in the clamping space R, the first welding mark S1 is located at the periphery of the positive projection of the first sealing surface 21.

[0068] The orthographic projection of the first sealing surface 21 at this location is the orthographic projection of the first sealing surface 21 along the first direction X at the tested end J of the test piece 200 located in the clamping space R.

[0069] Since the first weld mark S1 is located at the periphery of the orthographic projection of the first sealing surface 21, the first sealing surface 21 is basically in contact with the middle area of ​​the inspected end J, while avoiding the first weld mark S1 located at the edge of the inspected end J, so as not to seal the first weld mark S1 and allow it to leak.

[0070] Thus, the first sealing surface 21 can be a continuous surface continuously arranged in any direction, and there is no need to process a structure thereon to avoid the first weld mark S1 to allow air leakage from the first weld mark S1 . The first sealing gasket 20 has a simple structure and is easy to process.

[0071] Specifically, the first sealing gasket 20 may be a solid sealing gasket.

[0072] In some embodiments, reference Figure 6The second sealing gasket 30 has a second sealing surface 31 for abutting against the inspected end J, and the outer contour size of the second sealing surface 31 is the same as the outer contour size of the first sealing surface 21.

[0073] The second sealing surface 31 is configured such that, along the first direction X, an orthographic projection outer contour of the first sealing surface 21 coincides with an orthographic projection outer contour of the second sealing surface 31 .

[0074] At this time, the orthographic outer contours of the first sealing surface 21 and the second sealing surface 31 along the first direction X coincide with each other, and during the detection process, the first sealing surface 31 and the second sealing surface 31 do not seal the first welding mark S1 .

[0075] In actual application, whether the first sealing gasket 20 or the second sealing gasket 30 is arranged in the installation space, its sealing surface will not seal the first weld mark S1 when it abuts against the inspected end J of the test piece 200. The second sealing gasket 30 is arranged in the installation space to detect whether the second weld mark S2 corresponding to the sealing pin A2 is leaking. At this time, since the second sealing surface 31 does not seal the first weld mark S1, in order to avoid the first weld mark S1 interfering with the airtightness result of the second weld mark S2, in actual detection, the first sealing gasket 20 can be used to first detect the first test piece 200 that is not leaking at the first weld mark S1, and then the second test piece 200 with the same processing parameters of the first weld mark S1 as the first test piece 200 can be used to measure the airtightness at its second weld mark S2.

[0076] Since the outer contour dimensions of the first sealing surface 21 and the second sealing surface 31 are the same, in the actual production process, after the first sealing gasket 20 is mass-produced, the second sealing gasket 30 can be obtained by machining the avoidance hole k1 on the first sealing gasket 20, which helps to reduce the manufacturing cost of the second sealing gasket 30 and further reduce the cost of the airtightness detection device 100.

[0077] Moreover, in actual applications, the first weld mark S1 formed by the joint between the cover body A1 of the battery cell housing weldment and the shell may be extended to the side adjacent to the tested end J in addition to being located at the tested end J of the tested piece 200. If the second sealing surface 31 simply performs a single plane seal on the first weld mark S1 at the end surface of the tested piece, the sealing effect is often poor, otherwise the processing structure of the first sealing surface 21 becomes complicated. At this time, the strategy of not sealing the first weld mark S1 by the second sealing surface 31 is adopted, but whether there is a leak at the second weld mark S2 is judged based on the tested piece 200 whose detection structure is not leaky. The leak detection structure is not only reliable, but also helps to reduce the structural design of the first sealing pad 20, thereby reducing the cost of the airtightness detection device 100.

[0078] In other embodiments, the second sealing gasket 30 provided in the installation space can seal the first welding mark S1 .

[0079] That is, the second sealing surface 31 of the second sealing gasket 30 can cover and seal the first welding mark S1 when it contacts the test end J of the test piece 200. In one example, the first welding mark S1 is located at the periphery of the orthographic projection of the first sealing gasket 20 at the test end J, and the orthographic projection of the second sealing gasket 30 at the test end J can cover the first welding mark S1. At this time, the outer contour size of the second sealing surface 31 of the second sealing gasket 30 can be greater than the outer contour size of the first sealing surface 21 of the first sealing gasket 20.

[0080] Since the second sealing gasket 30 can seal the first welding mark S1, during the detection process, regardless of whether there is air leakage at the first welding mark S1 of the test piece 200, when the second sealing gasket 30 is used, as long as the test piece 200 leaks, it can be said that there is air leakage at the second welding mark S2, that is, the processing parameters corresponding to the second welding mark S2 need to be adjusted. That is, the order of using the first sealing gasket 20 and the second sealing gasket 30 in the detection process does not need to be limited, and the detection is more flexible.

[0081] In some embodiments, reference Figure 3 and Figure 5 The inflation portion 12 c is located at one side of the clamping tool 10 in the first direction X and is open toward the clamping space R so as to dock with the inflation hole q of the test piece 200 in the clamping space R in the first direction X.

[0082] In actual application, when the DUT 200 is installed in the clamping space R, the inflation hole q thereon is butted with the inflation portion 12c in the first direction X. It can be understood that the inflation hole q of the DUT 200 is located at one end in the first direction X thereof.

[0083] In this way, when the clamping tool 10 clamps the test piece 200, the inflation portion 12c can be firmly connected with the inflation hole q, which helps to improve the inflation reliability of the inflation portion 12c and the inflation hole q and reduce the probability of air leakage between the two.

[0084] Specifically in the embodiment, the inflation portion 12c includes an inflation cavity c1 and an inflation air path c2 communicating with the inflation cavity c1 . The clamping space R is located between the inflation cavity c1 and the exhaust portion 11a in the first direction X. The inflation cavity c1 is open toward the clamping space R.

[0085] The inflation portion 12c is formed by an inflation cavity c1 and an inflation path c2. Usually, the inflation cavity c1 is larger and can cover the periphery of the area where the inflation hole q is located when the DUT 200 is located in the clamping space R. The inflation path c2 is used to connect to an external air source.

[0086] If the first direction X corresponds to the height direction, the exhaust portion 11a can be located above the clamping space R, and the filling portion 12c is located below the clamping space R. This is suitable for airtightness testing of the test piece 200 whose filling hole q is located at the end opposite to the tested end J.

[0087] Of course, in other embodiments, the inflation portion 12 c and the exhaust portion 11 a are disposed on the same side of the clamping space R in the first direction X to meet the testing requirements of different types of DUTs 200 .

[0088] In some embodiments, reference Figure 3 , Figure 5 and Figure 7 The air tightness detection device 100 further includes a third sealing pad 40, which is disposed at the open end of the air filling cavity c1 and is used to seal the test piece 200. The third sealing pad 40 is provided with an air hole k2 for avoiding the air filling hole q and communicating with the air filling cavity c1.

[0089] The third sealing gasket 40 can be made of rubber, silicone or other materials, and is provided with an air hole k2. The third sealing gasket 40 can be annular. In actual application, the third sealing gasket 40 is sealed to connect the DUT 200 to prevent the gas in the inflation chamber c1 from leaking from the connection between the inflation chamber c1 and the DUT 200, thereby improving the reliability of the detection structure. The provision of the air hole k2 facilitates the gas in the inflation chamber c1 to enter the inflation hole q, thereby achieving normal inflation.

[0090] Specifically in the embodiment, refer to Figure 7 The open end of the inflation chamber c1 is provided with a second recessed groove 12d, and the third sealing gasket 40 is provided in the second recessed groove 12d and partially extends out of the second recessed groove 12d. The second recessed groove 12d is generally a straight groove, and is adaptively designed according to the structure of the third sealing gasket 40. The provision of the second recessed groove 12d can quickly locate the installation of the third sealing gasket 40.

[0091] In some embodiments, reference Figures 1 to 5 The clamping tool 10 includes a first clamping part 11, a second clamping part 12 and a connecting part 13. The first clamping part 11 and the second clamping part 12 are spaced apart from each other by a clamping space R in the first direction X. The connecting part 13 connects the first clamping part 11 and the second clamping part 12 and supports the first clamping part 11 and the second clamping part 12 to move relative to each other along the first direction X. The exhaust part 11a is provided at the first clamping part 11, and the inflation part 12c is provided at the second clamping part 12.

[0092] The first clamping part 11 and the second clamping part 12 can be in the shape of a plate, a block, or a seat, and the specific shape is not limited. The connecting part 13 connects and supports the first clamping part 11 and the second clamping part 12, and also allows the two to move relative to each other to change the size of the clamping space R between the two. For example, the connecting part 13 is a lifting cylinder. Usually, the first clamping part 11 is located above the second clamping part 12, and the clamping space R between the two is open in a direction perpendicular to the first direction X.

[0093] The inflation part 12c is arranged on the second pressing part 12, and the exhaust part 11a is arranged on the first pressing part 11. When the test piece 200 is installed between the first pressing part 11 and the second pressing part 12, its tested end J faces the exhaust part 11a, and its inflation hole q is connected with the inflation part 12c.

[0094] At this time, the pressing tool 10 has a simple structure, is easy to implement, and has a low manufacturing cost.

[0095] Of course, the pressing tool 10 may also be of other constructional forms, which can be obtained by conventional design by those skilled in the art.

[0096] Specifically in the embodiment, refer to Figures 1 to 5 The connecting part 13 includes a connecting column 13e and a clamping nut 13g, one end of the connecting column 13e is fixedly connected to the second clamping part 12, and the other end of the connecting column 13e is provided with an external threaded part 13f. The first clamping part 11 is movably sleeved on the connecting column 13e, and the clamping nut 13g is threadedly connected to the external threaded part 13f and is located on the side of the first clamping part 11 away from the second clamping part 12.

[0097] The external threaded portion 13f may be arranged only at one end of the connecting column 13e, or may extend to the entire column section of the connecting column 13e, and the specific details are not limited. The connecting column 13e is fixed to the second clamping portion 12, for example, fixed by tightening. The first clamping portion 11 may move relative to the connecting column 13e in the first direction X, and the first clamping portion 11 and the connecting column 13e may be clearance-fitted.

[0098] In actual application, when the test piece 200 is arranged between the first clamping part 11 and the second clamping part 12, the test piece 200 itself can support the first clamping part 11. When the first clamping part 11 and the first sealing gasket 20 or the second sealing gasket 30 are pressed on the test piece 200, the clamping nut 13g is rotated, and pressure is applied to the first clamping part 11 through the clamping nut 13g, so that the first sealing gasket 20 or the second sealing gasket 30 cooperates with the third sealing gasket 40 to tightly clamp the test piece 200, which can improve the reliability of the airtightness test result of the test piece 200.

[0099] In some embodiments, the pressing tool 10 further includes a bottom plate 50 , and the second pressing portion 12 is disposed on the bottom plate 50 .

[0100] In one embodiment of the present application, the airtightness detection device 100 includes the above-mentioned first clamping part 11, the connecting part 13 and the second clamping part 12, the first clamping part 11 is provided with an exhaust part 11a and a first groove 11b, the first clamping part 11 is provided with an inflation cavity c1 and a second groove 12d, and the first groove 11b can be selectively installed with either a first sealing gasket 20 or a second sealing gasket 30 that does not seal the first weld mark S1 of the test piece 200, and the second groove 12d is provided with a third sealing gasket 40.

[0101] In addition, the embodiment of the present application also provides a battery production system, including the airtightness detection device 100 in the above embodiment. The airtightness detection device 100 can be used for airtightness detection of various types of battery cells before assembly, and is specifically used for airtightness detection of the welding position of the battery cell cover A1 and the sealing pin A2.

[0102] In other embodiments, the battery production system may also include an air pump, an air source, etc. for supplying air to the airtightness detection device 100, and may also include welding equipment for welding between the cover body A1 and the shell, and between the sealing pin A2 and the cover body A1, as well as loading equipment for loading the electrode assembly into the battery cell shell, liquid injection equipment, formation equipment, aging test equipment, etc., which can be flexibly arranged by technical personnel in this field.

[0103] Specifically in the embodiment, refer to Figures 2 to 4 The airtightness detection device 100 is used for a cylindrical battery cell housing 200A to be inspected. The cylindrical battery cell housing 200A to be inspected includes a shell and a cover A1. The cover A1 is welded to one side of the shell in the first direction X. A sealing nail A2 is welded to the cover A1. The welding mark position of the cover A1 is used as the first welding mark S1, and the welding mark position of the sealing nail A2 is used as the second welding mark S2. A pole A3 is provided on the other side of the shell in the first direction X, and an inflation hole q is provided on the pole A3.

[0104] That is, in this embodiment, the airtightness detection device 100 is suitable for performing airtightness detection on a cylindrical battery case weldment. Specifically, the filling hole q of the cylindrical battery case weldment is arranged on its pole A3, and the first weld mark S1 and the second weld mark S2 are located at the other end opposite to the filling hole q.

[0105] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. An airtightness detection device, characterized in that: Used to detect the air tightness of a test piece (200) having an air filling hole (q), the test piece (200) having a first welding mark (S1) and a second welding mark (S2) at a test end (J) in a first direction (X), the first welding mark (S1) being located at the edge of the test end (J), and the second welding mark (S2) being located at the middle of the test end (J), the air tightness detection device comprising: A clamping tool (10) comprising a clamping space (R) for clamping the test piece (200) and having an adjustable spatial size in the first direction (X), and an inflation portion (12c) for docking with an inflation hole (q) of the test piece (200) located in the clamping space (R), the clamping tool (10) further comprising an exhaust portion (11a) and an installation space, the installation space being arranged in communication with the exhaust portion (11a) and the clamping space (R) in the first direction (X); A first sealing gasket (20) and a second sealing gasket (30), either of which is arranged in the installation space and abuts against the tested end (J) of the tested object (200), and the second sealing gasket (30) has an avoidance hole (k1); The first sealing gasket (20) provided in the installation space can seal the second welding mark (S2) and avoid the first welding mark (S1); the second sealing gasket (30) provided in the installation space, its avoidance hole (k1) can cover the second welding mark (S2) and connect to the exhaust part (11a).

2. The airtightness detection device according to claim 1, characterized in that: The pressing tool (10) is provided with a first sink (11b) open toward the clamping space (R), the exhaust portion (11a) is connected to the first sink (11b), and the installation space includes the internal space of the first sink (11b); The first sealing pad (20) and the second sealing pad (30) can be selectively arranged in the first sink groove (11b), and can partially extend out of the first sink groove (11b) to abut against the tested end (J) of the tested object (200).

3. The airtightness detection device according to claim 1 or 2, characterized in that: The first sealing pad (20) has a first sealing surface (21) for abutting against the detected end (J); The first sealing surface (21) is configured such that, on the tested end (J) of the test piece (200) located in the clamping space (R), the first welding mark (S1) is located at the periphery of the orthographic projection of the first sealing surface (21).

4. The airtightness detection device according to claim 3, characterized in that: The second sealing pad (30) has a second sealing surface (31) for abutting against the detected end (J), and the outer contour dimension of the second sealing surface (31) is the same as the outer contour dimension of the first sealing surface (21).

5. The airtightness detection device according to claim 1, characterized in that: The second sealing gasket (30) provided in the installation space can seal the first welding mark (S1).

6. The airtightness detection device according to claim 1, characterized in that: The inflation portion (12c) is located on one side of the pressing tool (10) in the first direction (X), and is open toward the clamping space (R) so as to dock with the inflation hole (q) of the test piece (200) located in the clamping space (R) in the first direction (X).

7. The airtightness detection device according to claim 6, characterized in that: The inflation portion (12c) comprises an inflation cavity (c1) and an inflation air path (c2) connected to the inflation cavity (c1); the clamping space (R) is located between the inflation cavity (c1) and the exhaust portion (11a) in the first direction (X); and the inflation cavity (c1) is open toward the clamping space (R).

8. The airtightness detection device according to claim 7, characterized in that: The air tightness detection device further comprises a third sealing gasket (40), which is arranged at the open end of the inflation cavity (c1) and is used for sealingly connecting the test piece (200); the third sealing gasket (40) is provided with an air hole (k2) for avoiding the inflation hole (q) and communicating with the inflation cavity (c1).

9. The airtightness detection device according to claim 8, characterized in that: The open end of the inflation cavity (c1) is provided with a second recessed groove (12d), and the third sealing gasket (40) is arranged in the second recessed groove (12d) and partially extends out of the second recessed groove (12d).

10. The airtightness detection device according to claim 1, characterized in that: The clamping tool (10) comprises a first clamping part (11), a second clamping part (12) and a connecting part (13), wherein the first clamping part (11) and the second clamping part (12) are spaced apart from each other by the clamping space (R) in the first direction (X), and the connecting part (13) connects the first clamping part (11) and the second clamping part (12), and supports the first clamping part (11) and the second clamping part (12) to move relative to each other along the first direction (X); The exhaust portion (11a) is arranged on the first pressing portion (11), and the inflation portion (12c) is arranged on the second pressing portion (12).

11. The airtightness detection device according to claim 10, characterized in that: The connecting part (13) includes a connecting column (13e) and a clamping nut (13g), one end of the connecting column (13e) is fixedly connected to the second clamping part (12), and the other end of the connecting column (13e) is provided with an external threaded part (13f), the first clamping part (11) is movably sleeved on the connecting column (13e), and the clamping nut (13g) is threadedly connected to the external threaded part (13f) and is located on the side of the first clamping part (11) away from the second clamping part (12).

12. A battery production system, characterized in that: Comprising the airtightness detection device as described in any one of claims 1 to 11.

13. The battery production system according to claim 12, characterized in that: The airtightness detection device is used for a cylindrical battery cell shell welded part (200A), the cylindrical battery cell shell welded part (200A) comprising a shell and a cover (A1), the cover (A1) being welded to one side of the shell in the first direction (X), a sealing pin (A2) being welded to the cover (A1), the welding mark position of the cover (A1) being the first welding mark (S1), and the welding mark position of the sealing pin (A2) being the second welding mark (S2); The housing is provided with a pole (A3) on the other side in the first direction (X), and the pole (A3) is provided with the inflation hole (q).

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