Device for measuring gas production rate of soft package battery

Abstract

The utility model provides a device for measuring the gas production rate of a soft package battery. The device comprises a conveying line, a compression roller mechanism and an air exhaust mechanism. A vacuum chuck for adsorbing a battery cell main body is arranged on the surface of the conveying end of the conveying line; the compression roller mechanism is mounted at the top of the conveying line, and the movable end of the compression roller mechanism is in contact with the battery cell main body and is used for rolling gas in the battery cell main body towards the gas bag side of the battery cell main body; the air exhaust mechanism comprises an air exhaust cylinder, an air collection pricking needle and a U-shaped liquid level pipe; an air inlet end is arranged at the bottom of the side wall of the exhaust cylinder; an air outlet end is arranged at the top of the side wall; the top of one end of the U-shaped liquid level pipe is connected with the air outlet end of the air suction cylinder through a pipeline. According to the utility model, through the matching of the compression roller mechanism and the conveying line, the gas in the battery cell main body is completely extruded and moved into the pre-sealing gas bag, and then the gas extraction mechanism is used for carrying out automatic gas extraction operation, so that the method difference of manual operation is avoided, the reading is accurate, and secondary damage to the battery cell is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of soft-pack battery measurement, in particular to a soft-pack battery gas production measurement device. Background Art

[0002] When the soft pack battery is formed, a certain amount of gas will be generated in the process of film formation, triggering a chain reaction, such as CH 4 , C 2 H 4 , CO and CO 2 The accumulation of gas will cause the expansion of the battery volume, increase of impedance and other problems, affecting the service life of the battery. At the same time, excessive thermal decomposition reaction will cause some safety hazards. Therefore, it is essential to test the gas production after the battery is formed.

[0003] The current methods for testing gas production include directly using a syringe to extract gas from a flat pre-sealed gas bag. This method is not easy to obtain complete gas, the extraction time is long, and it is easy to corrode the battery body, which can easily cause defects in the manufacturing process. There is also a method of using volume change to obtain gas production. This method is relatively cumbersome, difficult to operate, and rarely used. Utility Model Content

[0004] Based on this, it is necessary to provide a device for measuring the gas production of soft-pack batteries to address the problems that the existing test of the gas production of soft-pack batteries is difficult to operate and has large errors.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A device for measuring the gas production of a soft-pack battery comprises a conveying line, a pressing roller mechanism and a gas extraction mechanism.

[0007] The conveying end surface of the conveying line is provided with a vacuum suction cup for adsorbing the battery core body;

[0008] The pressing roller mechanism is installed on the top of the conveyor line, and the movable end of the pressing roller mechanism contacts the battery body to roll the gas inside the battery body to the air bag side of the battery body;

[0009] The air extraction mechanism includes an air extraction cylinder, an air collecting needle and a U-shaped liquid level tube; an air inlet end is arranged at the bottom of the side wall of the air extraction cylinder, and an air outlet end is arranged at the top of the side wall; the air collecting needle is connected to the air inlet end of the air extraction cylinder through a pipeline, and the top of one end of the U-shaped liquid level tube is connected to the air outlet end of the air extraction cylinder through a pipeline;

[0010] When the gas collecting needle is located in the air bag of the battery body and the vacuum pump completes the vacuuming, the liquid level change value of the U-shaped liquid level tube is read to know the gas production of the battery body.

[0011] Furthermore, the vacuum pump includes a cylinder body, a piston and a control cylinder; the two ends of the cylinder body are closed, the bottom and top of the side wall of the cylinder body respectively have an air inlet end and an air outlet end, the piston is placed in the cylinder body and fits against the inner wall of the cylinder, the control cylinder is installed on the top of the cylinder body, and the movable end of the control cylinder passes through the top of the cylinder body and is fixedly connected to the piston.

[0012] Furthermore, a sealing rubber plug is provided between the movable end of the control cylinder and the top of the cylinder body.

[0013] Furthermore, the air inlet end of the cylinder is connected to an air inlet pressure gauge, and the side wall of the air outlet end of the cylinder extends longitudinally upward to form an extension portion, which is connected to the cylinder and the interior of the U-shaped liquid level tube, and the end of the extension portion is connected to a balance pressure gauge, and a valve is provided in the middle section of the extension portion.

[0014] Furthermore, the pressure roller mechanism includes a fixed bracket, an anti-corrosion pressure roller, a telescopic cylinder and a spring; the fixed bracket is installed in the middle section of the top of the conveyor line, the fixed end of the telescopic cylinder is connected to the fixed bracket, and the movable end is in contact with the end of the anti-corrosion pressure roller. The two ends of the anti-corrosion pressure roller are longitudinally slidably arranged on the fixed bracket, and the spring is arranged between the bottom of the fixed bracket and the anti-corrosion pressure roller to push the anti-corrosion pressure roller upward.

[0015] Furthermore, the pressing roller mechanism also includes a support frame, a pressure plate and two telescopic cylinders; the support frame is installed on the top of the conveyor line and is located next to the fixed bracket, the support frame is close to the end position of the conveying direction of the conveyor line, the fixed end of the two telescopic cylinders is connected to the support frame, and the movable end faces downward and is connected to the pressure plate.

[0016] Furthermore, sensors for sensing the position of the battery cell body are installed at the top of the conveyor line close to the anti-corrosion pressure roller and the pressure plate.

[0017] Furthermore, limiting plates for limiting the battery cell body are installed on both sides of the top of the conveyor line. The limiting plates are staggered with the fixed bracket and the support frame, and the length direction of the limiting plates is consistent with the conveying direction of the conveyor line.

[0018] Furthermore, the height of the limiting plate is 5-7 mm lower than the thickness of the battery cell body, and the conveying speed of the conveyor line is at most 25 m / s.

[0019] Furthermore, the surface of the U-shaped liquid level tube has scale lines for reading the liquid level change of the U-shaped liquid level tube.

[0020] Compared with the prior art, the beneficial effects of the utility model include:

[0021] 1. The utility model completely squeezes the gas inside the battery body and moves it to the pre-sealed air bag through the cooperation of the roller mechanism and the conveyor line, and then automatically evacuates the gas through the exhaust mechanism. After the test, the battery can flow to the next process normally. This method can more accurately extract the gas in the battery, without the difference of manual operation, accurate reading, and will not cause secondary damage to the battery;

[0022] 2. The pressure roller mechanism of the utility model cooperates with the anti-corrosion pressure roller and the pressure plate. After the anti-corrosion pressure roller squeezes the gas in the battery cell body into the air bag, the pressure plate can clamp the battery cell body after rolling to reduce gas reflux, so that the exhaust mechanism can extract complete exhaust. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The disclosure of the present invention is described with reference to the accompanying drawings. It should be understood that the drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings, the same reference numerals are used to refer to the same components. Among them:

[0024] Figure 1 This is a schematic diagram of the battery cell body introduced in the utility model;

[0025] Figure 2 This is a schematic diagram of the structure of the pressure roller mechanism and the conveying line introduced in the utility model;

[0026] Figure 3 This is a schematic diagram of the structure of the air extraction mechanism introduced in the utility model;

[0027] Figure 4 The utility model introduces a front view of a device for measuring the gas production of a soft-pack battery.

[0028] Explanations in the figure: 1. Conveyor line; 11. Vacuum suction cup; 2. Pressing roller mechanism; 21. Fixed bracket; 22. Anti-corrosion pressing roller; 23. Telescopic cylinder one; 24. Spring; 25. Support frame; 26. Pressing plate; 27. Telescopic cylinder two; 3. Vacuum mechanism; 31. Vacuum cylinder; 311. Cylinder body; 312. Piston; 313. Control cylinder; 314. Sealing rubber plug; 32. Gas collecting needle; 33. U-shaped liquid level tube; 34. Inlet pressure gauge; 35. Balance pressure gauge; 36. Valve; 4. Sensor; 5. Limit plate. DETAILED DESCRIPTION

[0029] It is easy to understand that according to the technical solution of the utility model, without changing the essential spirit of the utility model, a person skilled in the art can propose a variety of interchangeable structural modes and implementation modes. Therefore, the following specific implementation modes and drawings are only exemplary descriptions of the technical solution of the utility model, and should not be regarded as the entirety of the utility model or as a limitation or restriction to the technical solution of the utility model.

[0030] See also Figure 4 This embodiment introduces a gas production measuring device for soft-pack batteries, which is mainly composed of a conveyor line 1, a roller mechanism 2 and an exhaust mechanism 3. The conveyor line 1 of this embodiment is preferably a belt conveyor line, which is mainly composed of a frame, a conveyor belt, a driving mechanism, a control mechanism, etc. Since the conveyor line 1 adopts the existing structure, it will not be described in detail here. The conveyor belt serves as the conveying end of the conveyor line 1, and the surface has a plurality of evenly arranged vacuum suction cups 11, which are used to adsorb the battery cell body and limit the battery cell body.

[0031] like Figure 2 As shown, in order to further limit the battery cell body, the limit plates 5 are symmetrically installed on the top of the frame. The limit plates 5 are located on both sides of the conveyor belt. The length direction of the limit plates 5 is consistent with the conveying direction of the conveyor belt. The spacing between the two limit plates 5 is adapted to the size of the battery cell body. The limit plates 5 can further prevent the battery cell body from escaping from the conveyor belt. It should be noted that the height of the limit plate 5 is 5-7mm lower than the thickness of the battery cell body to ensure that the roller mechanism 2 can be completely pressed on the battery cell body. The conveying speed of the conveyor belt is ≤25m / s, so that the battery cell body passes through the roller mechanism 2 at a suitable speed.

[0032] For the convenience of introducing the cooperation between the pressing roller mechanism 2, the exhaust mechanism 3 and the battery body, as shown in FIG. Figure 1 As shown, it is a schematic diagram of the battery cell body. It can be seen that one side of the battery cell body is the air bag side, and the roller mechanism 2 can roll the gas inside the battery cell body toward the air bag side so that all the gas is located in the air bag.

[0033] like Figure 2 As shown, the roller mechanism 2 is installed on the top of the conveyor line 1, or more precisely, on the top of the frame of the conveyor line 1, and is located above the conveyor belt. The roller mechanism 2 includes a fixed bracket 21, an anti-corrosion roller 22, a telescopic cylinder 1 23, a spring 24, a support frame 25, a pressure plate 26, and a telescopic cylinder 2 27. The fixed bracket 21 is similar to the Π-type, and the support frame 25 is similar to the U-type, which is connected to the top of the frame of the conveyor line 1. The two are arranged adjacently. The fixed bracket 21 is located in the middle of the conveyor line 1, and the support frame 25 is located at the end of the conveying direction of the conveyor line 1. The battery body first passes through the fixed bracket 21 and then to the support frame 25. The fixed end of the telescopic cylinder 1 23 is longitudinally installed on the fixed bracket 21, and the movable end is downward. Since the two ends of the anti-corrosion roller 22 are longitudinally slidably connected to the fixed bracket 21, in order to prevent the telescopic cylinder 1 23 from affecting the rotation of the anti-corrosion roller 22 itself, the movable end of the telescopic cylinder 1 23 contacts the end of the anti-corrosion roller 22.

[0034] Specifically, the anti-corrosion roller 22 is made of corrosion-resistant material, and a sliding protrusion is sleeved on its end. The shaft end of the anti-corrosion roller 22 is rotatably connected to the rectangular sliding protrusion, that is, the anti-corrosion roller 22 can rotate. A sliding opening is opened on the side of the fixed bracket 21. The sliding protrusion is located in the sliding opening and is slidably arranged. The sliding protrusion extends horizontally outward, so that the movable end of the telescopic cylinder 23 can contact the sliding protrusion without affecting the rotation of the anti-corrosion roller 22. The spring 24 is arranged between the bottom of the sliding opening and the sliding protrusion to support the sliding protrusion and push the sliding protrusion upward. When it is necessary to roll the battery cell body, the telescopic cylinder 23 is driven to move downward, so that the roller contacts the battery cell body and rolls it. With the transportation of the conveyor line 1, the gas in the battery cell body can be rolled to the air bag side.

[0035] The top of the support frame 25 is connected to the fixed end of the telescopic cylinder 27. The telescopic cylinder 27 is arranged longitudinally and the movable end is downward and connected to the pressure plate 26. When the non-airbag position of the battery cell body is completely moved to the bottom of the pressure plate 26, the telescopic cylinder 27 is extended to make the pressure plate 26 move down to clamp the battery cell body, which can avoid the situation of gas backflow. In order to facilitate the sensing of the position of the battery cell body, the top of the conveyor line 1 is close to the anti-corrosion roller and the pressure plate 26. Sensors 4 for sensing the position of the battery cell body are installed, so that the battery cell body can be sensed after it moves to the anti-corrosion roller and the pressure plate 26, thereby controlling the telescopic cylinder 1 23 and the telescopic cylinder 27 to start. It should be noted that the sensor 4 is preferably an embedded anti-radiation sensing optical fiber, and the embedded anti-radiation sensing optical fiber is located at the pressure plate 26 close to the side of the pressure plate 26 away from the anti-corrosion roller.

[0036] like Figure 3 As shown, the air extraction mechanism 3 is mainly composed of an air extraction cylinder 31, an air collecting needle 32 and a U-shaped liquid level tube 33. The air extraction cylinder 31 includes a cylinder body 311, a piston 312 and a control cylinder 313. The cylinder body 311 is closed at both ends, and the bottom and top of the side wall of the cylinder body 311 respectively have an air inlet end and an air outlet end. The air inlet end and the air outlet end can be located on the same side or staggered, preferably staggered. The piston 312 is placed in the cylinder body 311 and fits the inner wall of the cylinder body 311. The piston 312 is located above the air inlet end and does not affect the entry of gas. The air inlet end and the air outlet end are both connected to pipelines for connection with other structures. The control cylinder 313 is installed on the top of the cylinder body 311. The movable end of the control cylinder 313 passes through the top of the cylinder body 311 and is fixed to the piston 312. In order to avoid air leakage caused by a gap between the movable end of the control cylinder 313 and the top of the cylinder 311, a sealing rubber plug 314 is provided at the top of the cylinder 311 and the movable end of the control cylinder 313 to fill the gap therebetween.

[0037] The gas collecting needle 32 is connected to the air inlet end pipeline of the cylinder 311, and the U-shaped liquid level tube 33 is connected to the air outlet end pipeline of the cylinder 311. When the gas collecting needle 32 is inserted into the air bag, the piston 312 can be moved upward by controlling the cylinder 313 to perform the air extraction operation, and then the gas volume can be known by the liquid level change of the U-shaped liquid level tube 33. The surface of the U-shaped liquid level tube 33 has scale lines for reading the liquid level change of the U-shaped liquid level tube 33. In order to conveniently know whether the air pressure at the air inlet and air outlet ends of the air extraction cylinder 31 is consistent, the air inlet end of the cylinder 311 is connected to an air inlet pressure gauge 34, and the side wall of the air outlet end of the cylinder 311 extends longitudinally upward to form an extension part, which is connected to the cylinder 311 and the U-shaped liquid level tube 33. The end of the extension part is connected to a balance pressure gauge 35, and the middle section of the extension part is provided with a valve 36. The valve 36 is preferably a solenoid valve. Before air is pumped out, the valve 36 is opened, and the values ​​of the air intake pressure gauge 34 and the balance pressure gauge 35 can be observed to see whether they are consistent. If they are consistent, the valve 36 can be closed, and then the air collection needle 32 is inserted into the air bag to pump air.

[0038] It should be noted that, in order to facilitate the fixation of the vacuum pump 31 and the U-shaped liquid level tube 33, the vacuum pump 31 and the U-shaped liquid level tube 33 can be installed inside the box, and the air collecting needle 32, the air intake pressure gauge 34 and the balance pressure gauge 35 are placed outside the box. At the same time, a reading window for observing the value of the U-shaped liquid level tube 33 is set on the surface of the box.

[0039] The specific measurement method is as follows:

[0040] (1) The formed battery cell body is placed flat with the air pocket facing outward on a conveyor belt with a vacuum suction cup 11;

[0041] (2) The battery cell body moves to the anti-corrosion roller and enters the nearby optical fiber sensing area, and the telescopic cylinder 23 applies pressure to the anti-corrosion roller 22 according to the set parameters to act on the surface of the battery cell body passing through the anti-corrosion roller 22;

[0042] (3) The cell body after rolling is moved to the counter-inductive optical fiber area of ​​the pressing plate 26, the conveyor belt is suspended, and the telescopic cylinder 27 applies pressure to the pressing plate 26 on the surface of the cell body according to the set parameters;

[0043] (4) The conveyor belt is transported at a speed of ≤25m / s, and the anti-corrosion roller 22 rolls toward the air bag edge; before rolling, it is necessary to check that there is no foreign matter on the surface of the anti-corrosion roller 22 to ensure that the appearance of the battery cell will not be poor during the rolling process;

[0044] (5) After the pressing plate 26 presses the battery cell, the gas extraction mechanism 3 is used to extract gas from the pre-sealed gas bag;

[0045] (6) Pumping requirements: Before pumping, reset the piston 312, open the valve 36, observe that the readings of the intake pressure gauge 34 and the balance pressure gauge 35 are consistent, then close the valve 36 and record the reading V0 of the U-shaped liquid level tube 33;

[0046] (7) The gas collection needle 32 punctures the side edge of the air bag, and the puncture opening is covered with a high-viscosity tape to prevent air leakage during the air extraction process;

[0047] (8) Control the cylinder 313 to contract and evacuate the air. After observing that the air in the air bag is exhausted, read the reading V1 of the U-shaped liquid level tube 33. The gas production of the battery cell = V1-V0;

[0048] (9) After the reading is completed, open the valve 36, remove the needle, and reset the control cylinder 313, and the test is completed;

[0049] (10) After testing, the battery cell is sealed again and flows into the next process normally.

[0050] Four groups of cells were taken respectively, and the gas volume was extracted using the traditional method and the method of this embodiment, while the outflow of electrolyte was visually observed. The specific situation is as follows:

[0051]

[0052]

[0053] By rolling the battery cell, the gas inside the battery cell body is rolled and squeezed into the pre-sealed air bag, and the gas is extracted by the exhaust mechanism 3. Compared with the traditional method, this method collects gas more thoroughly and the data is more accurate. At the same time, it will not cause any adverse effects on the appearance of the battery cell and will not extract excess electrolyte to corrode the battery cell body. The tested battery cell can flow to the next process normally. By adjusting the rolling pressure, the bubbles between the layers inside the battery cell are completely squeezed into the air bag, and then clamped by the pressing plate 26 after rolling, which can effectively prevent the gas squeezed into the air bag from flowing back. This method squeezes the gas in the battery cell body into the air bag to the maximum extent, and the gas measurement result is more accurate. The exhaust mechanism 3 avoids the error in the amount of exhaust caused by manual operation, and the compartment-type exhaust cavity avoids the contact between the gas and the U-shaped liquid level tube 33 to the maximum extent, reduces the measurement error caused by the gas-liquid interaction, and the use of the U-shaped liquid level tube 33 with a scale makes the measurement reading more accurate.

[0054] The technical scope of the present invention is not limited to the contents described above. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical concept of the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. A device for measuring gas production of a soft-pack battery, characterized in that: It includes: A conveying line (1), the conveying end surface of which is provided with a vacuum suction cup (11) for adsorbing the battery cell body; A pressing roller mechanism (2) is installed on the top of the conveyor line (1), and the movable end of the pressing roller mechanism (2) is in contact with the battery cell body, so as to roll the gas inside the battery cell body toward the air bag side of the battery cell body; The air extraction mechanism (3) comprises an air extraction cylinder (31), an air collecting needle (32) and a U-shaped liquid level tube (33); the bottom of the side wall of the air extraction cylinder (31) is provided with an air inlet end, and the top of the side wall is provided with an air outlet end; the air collecting needle (32) is connected to the air inlet end of the air extraction cylinder (31) through a pipeline, and the top of one end of the U-shaped liquid level tube (33) is connected to the air outlet end of the air extraction cylinder (31) through a pipeline; When the gas collecting needle (32) is located in the air bag of the battery cell body and the vacuum cylinder (31) completes the vacuuming, the liquid level change value of the U-shaped liquid level tube (33) is read to know the gas production of the battery cell body.

2. The gas production measurement device for soft-pack batteries according to claim 1, characterized in that: The vacuum cylinder (31) comprises a cylinder (311), a piston (312) and a control cylinder (313); the cylinder (311) is closed at both ends, the bottom and top of the side wall of the cylinder (311) respectively have an air inlet end and an air outlet end, the piston (312) is placed in the cylinder (311) and fits with the inner wall of the cylinder (311), the control cylinder (313) is installed on the top of the cylinder (311), and the movable end of the control cylinder (313) vertically passes through the top of the cylinder (311) and is fixedly connected to the piston (312).

3. The gas production measurement device for a soft-pack battery according to claim 2, characterized in that: A sealing rubber plug (314) is provided between the movable end of the control cylinder (313) and the top of the cylinder (311).

4. The gas production measurement device for a soft-pack battery according to claim 2, characterized in that: The air inlet end of the cylinder (311) is connected to an air inlet pressure gauge (34), and the side wall of the air outlet end of the cylinder (311) extends longitudinally upward to form an extension portion, the extension portion is connected to the cylinder (311) and the inside of the U-shaped liquid level tube (33), the end of the extension portion is connected to a balance pressure gauge (35), and the middle section of the extension portion is provided with a valve (36).

5. The gas generation measurement device for soft-pack batteries according to claim 1, characterized in that: The pressure roller mechanism (2) comprises a fixed bracket (21), an anti-corrosion pressure roller (22), a telescopic cylinder (23) and a spring (24); the fixed bracket (21) is installed at the middle section of the top of the conveyor line (1); the fixed end of the telescopic cylinder (23) is connected to the fixed bracket (21), and the movable end is in contact with the end of the anti-corrosion pressure roller (22); the two ends of the anti-corrosion pressure roller (22) are longitudinally slidably arranged on the fixed bracket (21); the spring (24) is arranged between the bottom of the fixed bracket (21) and the end of the anti-corrosion pressure roller (22) to push the anti-corrosion pressure roller (22) upward.

6. The gas generation measurement device for a soft-pack battery according to claim 5, characterized in that: The pressing roller mechanism (2) also includes a support frame (25), a pressing plate (26) and a second telescopic cylinder (27); the support frame (25) is installed on the top of the conveying line (1) and is located beside the fixed support (21), the support frame (25) is close to the end position of the conveying direction of the conveying line (1), and the second telescopic cylinder (27) has a fixed end connected to the support frame (25) and a movable end facing downward and connected to the pressing plate (26).

7. The gas generation measurement device for soft-pack batteries according to claim 6, characterized in that: Sensors (4) for sensing the position of the battery core body are installed at the top of the conveyor line (1) close to the anti-corrosion pressure roller (22) and the pressure plate (26).

8. The gas generation measurement device for a soft-pack battery according to claim 6, characterized in that: Limiting plates (5) for limiting the battery cell bodies are installed on both sides of the top of the conveyor line (1); the limiting plates (5) are staggered with the fixed bracket (21) and the support frame (25); and the length direction of the limiting plates (5) is consistent with the conveying direction of the conveyor line (1).

9. The gas generation measurement device for a soft-pack battery according to claim 8, characterized in that: The height of the limiting plate (5) is 5-7 mm lower than the thickness of the battery core body, and the conveying speed of the conveying line (1) is at most 25 m / s.

10. The gas generation measurement device for a soft-pack battery according to claim 1, characterized in that: The surface of the U-shaped liquid level tube (33) is provided with scale lines for reading the liquid level change of the U-shaped liquid level tube (33).

Images