Soft package battery air tightness detection device

Abstract

The utility model discloses an air tightness detection device for a soft package battery. The air tightness detection device comprises a sealing box capable of being opened and closed, a pressing assembly arranged in the sealing box, a first guide rod connected with the pressing assembly, a power transmission mechanism driving the first guide rod to move up and down, and a pressure measuring pipe communicated with the sealing box, wherein the first guide rod penetrates through the top of the sealing box and is movably and hermetically connected with the sealing box; the pressure measuring pipe comprises a sealed visible pipe body and a floating piece which is arranged in the visible pipe body and can move along with air flow. According to the utility model, the air tightness of the soft package lithium battery is detected by extruding the soft package lithium battery in the downward moving process of the downward pressing assembly, when the soft package lithium battery leaks air, the internal pressure of the box body changes, and under the action of pressure difference, the floating block moves in the visible tube body, so that the air tightness of the soft package lithium battery is detected. Therefore, whether the soft package lithium battery leaks air or not can be judged by observing the movement condition of the floating block without the help of a pressure sensor.

Description

Technical Field

[0001] The utility model relates to the technical field of soft-pack lithium batteries, in particular to an air tightness detection device for soft-pack batteries. Background Art

[0002] Soft-pack lithium battery is a common lithium battery with advantages such as good safety performance, light weight, large capacity, small internal resistance, and flexible appearance design. The internal chemical system of lithium battery is active and it is very easy to react with external moisture and air, resulting in battery performance degradation or failure. Therefore, the air tightness of the package is crucial to the reliability and safety of lithium battery. How to effectively detect the air tightness of soft-pack lithium battery to improve R&D efficiency and ensure that defective packaged products will not flow into the consumer market is of great significance. The existing air tightness detection method for square shell lithium battery is helium detection method, that is, helium is injected into the battery through the air inlet hole on the shell, and the helium detector is used to detect whether there is helium leakage inside the battery pack, so as to achieve the purpose of air tightness detection. However, since the soft-pack battery cell cannot be opened, the conventional helium detection method cannot complete the air tightness detection of the soft-pack battery cell. Utility Model Content

[0003] The purpose of the utility model is to provide a soft-pack battery airtightness detection device to solve the problems raised in the above-mentioned background technology and realize the rapid airtightness detection of the soft-pack battery without the aid of a pressure sensor.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] The utility model discloses an airtightness detection device for a soft-pack battery, comprising an openable and closable sealing box, a pressing assembly arranged in the sealing box, a first guide rod connected to the pressing assembly, a power transmission mechanism driving the first guide rod to move up and down, and a pressure measuring tube connected to the sealing box; wherein the first guide rod passes through the top of the sealing box and the two are movably and hermetically connected; the pressure measuring tube comprises a sealed visible tube body and a floating part arranged in the visible tube body and movable with airflow.

[0006] Furthermore: the pressing assembly includes a movable plate connected to the first guide rod, a pressure plate arranged below the movable plate and parallel to the movable plate, a second guide rod connecting the pressure plate and the movable plate, an elastic member sleeved on the outer periphery of the second guide rod, and a limiting ring fixed to the outer periphery of the second guide rod; the bottom end of the second guide rod is fixed to the pressure plate, the top end passes through the movable plate and is movably connected to it, and the limiting ring is located above the movable plate; the two ends of the elastic member are respectively in contact with the pressure plate and the movable plate.

[0007] Furthermore: the sealed box comprises a box body with an opening facing upward and a box cover arranged at the opening of the box body; the box body and the box cover are detachably connected by fasteners.

[0008] Furthermore: the edges of the box body and the box cover are correspondingly provided with through grooves for accommodating fasteners, and the fasteners include a connecting rod arranged in the through groove, a rotating shaft vertically connected to the lower end of the connecting rod, a U-shaped seat movably sleeved at both ends of the rotating shaft, and a fastening nut threadedly connected to the upper end of the connecting rod; the U-shaped seat is fixedly connected to the side wall of the box body.

[0009] Furthermore: it also includes an air pipe for connecting to a vacuum pump and a valve arranged on the air pipe; the air pipe is connected to a sealing box.

[0010] Furthermore: the sealed box also includes handles symmetrically arranged on the box cover.

[0011] Furthermore: the sealed box also includes a sealing block arranged at the bottom end of the box cover, and the sealing block abuts against the box body.

[0012] Further: the outer wall of the visual tube body is provided with scale marks.

[0013] Further: the power transmission mechanism is a hydraulic cylinder.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] The utility model detects the air tightness of the soft-pack lithium battery by squeezing the soft-pack lithium battery during the downward movement of the pressing component. When the soft-pack lithium battery leaks, the pressure inside the box changes. Under the action of the pressure difference, the floating block moves inside the visual tube body, so that by observing the movement of the floating block, it is possible to judge whether the soft-pack lithium battery is leaking without the help of a pressure sensor. This detection device has a simple structure, is easy to operate, and has high screening efficiency. In a vacuum environment, the air tightness of the soft-pack lithium battery can be judged according to the change in the position of the floating block, which effectively improves the detection of the air tightness of the soft-pack lithium battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the three-dimensional structure of the utility model;

[0017] Figure 2 It is a side sectional view of the utility model;

[0018] Figure 3 for Figure 1 A partial enlarged view of the middle part;

[0019] In the figure: 1-sealed box, 11-box body, 12-box cover, 13-through groove, 14-handle, 15-sealing block, 2-pressing assembly, 21-movable plate, 22-pressing plate, 23-second guide rod, 24-elastic member, 25-limiting ring, 3-first guide rod, 4-power transmission mechanism, 5-pressure measuring tube, 51-visible tube body, 52-floating member, 53-scale mark, 6-fastener, 61-connecting rod, 62-rotating shaft, 63-U-shaped seat, 64-fastening nut, 7-trachea, 8-valve. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] In the description of the present utility model, it should be noted that the terms "upper", "lower", "left", "right", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present utility model.

[0022] See also Figure 1-3 In this embodiment, a soft-pack battery airtightness detection device includes an openable and closable sealed box 1, a pressing assembly 2 disposed in the sealed box 1, a first guide rod 3 connected to the pressing assembly 2, a power transmission mechanism 4 driving the first guide rod 3 to move up and down, and a pressure measuring tube 5 connected to the sealed box 1; wherein the first guide rod 3 passes through the top of the sealed box 1 and the two are movably and sealedly connected; the pressure measuring tube 5 includes a sealed visual tube body 51 and a floating part 52 disposed in the visual tube body 51 and movable with the airflow. The soft-pack battery to be tested is placed in the beehive 1, and the pressing assembly 2 applies pressure to the soft-pack battery. If the battery leaks, the air pressure in the sealed box 1 will change, and the air pressure will be transmitted to the visual tube body 51, and the floating part 52 will float upward under the action of the airflow; if the battery does not leak, the air pressure in the sealed box 1 will remain unchanged, and the floating part 52 will not float. The airtightness of the soft-pack battery is judged by the state of the floating part 52.

[0023] Furthermore, the pressing assembly 2 includes a movable plate 21 connected to the first guide rod 3, a pressure plate 22 arranged below and parallel to the movable plate 21, a second guide rod 23 connecting the pressure plate 22 and the movable plate 21, an elastic member 24 sleeved on the outer periphery of the second guide rod 23, and a limit ring 25 fixed to the outer periphery of the second guide rod 23; the bottom end of the second guide rod 23 is fixed to the pressure plate 22, the top end passes through the movable plate 21 and is movably connected thereto, and the limit ring 25 is located above the movable plate 21; the two ends of the elastic member 24 are respectively in contact with the pressure plate 22 and the movable plate 21. In this embodiment, the elastic member 24 is a spring, and the power transmission mechanism 4 is a hydraulic cylinder. The hydraulic cylinder drives the first guide rod 23 to move downward, and the movable plate 21 to move downward. The downward movement height of the movable plate 21 is preset. The pressure plate 22 directly acts on the soft-pack battery. When the pressure plate 22 contacts the battery surface, the spring is compressed to provide a buffer for the pressure on the soft-pack battery, thereby preventing the battery from being damaged due to excessive pressure.

[0024] Furthermore, the visible tube body 51 is a transparent tempered glass tube, and a scale mark 53 is provided on the tube wall, which is used to measure the displacement of the floating member 52, so as to judge the degree of leakage of the soft pack battery. A support platform for placing the floating member 52 is provided at the bottom of the tempered glass tube, and a pipeline is opened in the support platform, which is connected to the inside of the sealing box 1; the outer wall of the floating member 52 is in close sealing contact with the inner wall of the tempered glass tube, and when the air pressure at the bottom of the floating member 52 increases, the floating member 52 can easily move up with it. The material of the floating member 52 is bakelite.

[0025] Furthermore, the sealed box 1 comprises a box body 11 with an opening facing upward, and a box cover 12 covering the opening of the box body 11; the box body 11 and the box cover 12 are detachably connected by a fastener 6. The upper end of the box body 11 is provided with an outwardly turned skirt to facilitate fixation when connected with the box cover 12. The bottom end of the box cover 12 is provided with a soft sealing block 15. When the box cover is closed, the surrounding of the sealing block 15 abuts against the inner wall of the box body 11, and the sealing performance is good.

[0026] Furthermore, the edges (skirts) of the box body 11 and the box cover 12 are correspondingly provided with through grooves 13 for accommodating the fastener 6, and the fastener 6 comprises a connecting rod 61 arranged in the through groove 13, a rotating shaft 62 vertically connected to the lower end of the connecting rod 61, a U-shaped seat 63 movably sleeved at both ends of the rotating shaft 62, and a fastening nut 64 threadedly connected to the upper end of the connecting rod 61; the U-shaped seat 63 is fixedly connected to the side wall of the box body 11. The connecting rod 61 can rotate around the U-shaped seat, and the top end of the connecting rod 61 has a thread, which can be threadedly connected to the fastening nut 64. By rotating the fastening nut 64, the box cover 12 can be pressed to improve air tightness. The fastening nut is preferably a ram nut for easy operation.

[0027] Furthermore, the device further comprises an air pipe 7 for connecting to a vacuum pump and a valve 8 arranged on the air pipe 7; the air pipe 7 is connected to the sealed box 1. Before the test, the sealed box 1 is evacuated to make it easier to observe the pressure change in the box.

[0028] Furthermore, the sealed box 1 also includes a handle 14 symmetrically arranged on the box cover 12 to facilitate the opening and closing operation of the box cover.

[0029] When the utility model is in use, firstly, the soft-pack battery to be tested is placed in the box body 11, and then the fastener 6 is used to lock the box body 11 and the box cover 12, and the vacuum pump is started to evacuate the box to a vacuum, and then the hydraulic cylinder is started to push the movable plate 21 to move, and the pressure plate 22 is also moved downward by the transmission of the first guide rod 3. The pressure plate 22 squeezes the soft-pack battery during the downward movement. When the soft-pack battery has a leak, the pressure in the box increases. Under the action of the pressure difference, the floating piece 52 moves up in the visual tube body 51, and whether the battery is leaking is judged by observing the movement of the floating block 52, thereby screening qualified batteries.

[0030] Although this specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0031] Therefore, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application; that is, all equivalent changes made according to the scope of the claims of the present application are within the protection scope of the claims of the present application.

Claims

1. A soft pack battery air tightness detection device, characterized in that: The invention comprises an openable and closable sealing box (1), a pressing assembly (2) arranged in the sealing box (1), a first guide rod (3) connected to the pressing assembly (2), a power transmission mechanism (4) for driving the first guide rod (3) to move up and down, and a pressure measuring tube (5) connected to the sealing box (1); wherein the first guide rod (3) passes through the top of the sealing box (1) and the two are movably and hermetically connected; the pressure measuring tube (5) comprises a sealed visible tube body (51) and a floating member (52) arranged in the visible tube body (51) and movable with the airflow.

2. The air tightness detection device for soft-pack batteries according to claim 1, characterized in that: The pressing assembly (2) comprises a movable plate (21) connected to the first guide rod (3), a pressing plate (22) arranged below the movable plate (21) and parallel thereto, a second guide rod (23) connecting the pressing plate (22) and the movable plate (21), an elastic member (24) sleeved on the outer periphery of the second guide rod (23), and a limiting ring (25) fixed to the outer periphery of the second guide rod (23); the bottom end of the second guide rod (23) is fixed to the pressing plate (22), the top end passes through the movable plate (21) and is movably connected thereto, and the limiting ring (25) is located above the movable plate (21); the two ends of the elastic member (24) are respectively in contact with the pressing plate (22) and the movable plate (21).

3. The air tightness detection device for soft-pack batteries according to claim 1, characterized in that: The sealed box (1) comprises a box body (11) with an opening facing upward and a box cover (12) arranged on the opening of the box body (11); the box body (11) and the box cover (12) are detachably connected via a fastener (6).

4. The air tightness detection device for soft-pack batteries according to claim 3, characterized in that: The edges of the box body (11) and the box cover (12) are correspondingly provided with through grooves (13) for accommodating a fastener (6); the fastener (6) comprises a connecting rod (61) arranged in the through groove (13), a rotating shaft (62) vertically connected to the lower end of the connecting rod (61), a U-shaped seat (63) movably sleeved on both ends of the rotating shaft (62), and a fastening nut (64) threadedly connected to the upper end of the connecting rod (61); the U-shaped seat (63) is fixedly connected to the side wall of the box body (11).

5. The air tightness detection device for soft-pack batteries according to claim 1, characterized in that: It also comprises an air pipe (7) for connecting to a vacuum pump and a valve (8) arranged on the air pipe (7); the air pipe (7) is connected to the sealing box (1).

6. The air tightness detection device for soft-pack batteries according to claim 3, characterized in that: The sealed box (1) also includes a handle (14) symmetrically arranged on the box cover (12).

7. The air tightness detection device for soft-pack batteries according to claim 3, characterized in that: The sealed box (1) also includes a sealing block (15) arranged at the bottom end of the box cover (12), and the sealing block (15) is in abutment with the box body (11).

8. The air tightness detection device for soft-pack batteries according to claim 1, characterized in that: The outer wall of the visual tube body (51) is provided with scale marks (53).

9. The air tightness detection device for soft-pack batteries according to claim 1, characterized in that: The power transmission mechanism (4) is a hydraulic cylinder.

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