Full-automatic air permeability detection device and method for lithium ion battery separator

Abstract

The present application relates to the field of air permeability detection device, disclose a kind of lithium ion battery separator full-automatic air permeability detection device and method, lithium ion battery separator full-automatic air permeability detection device includes: thermostat, thermostat is provided with in: separator unwinding assembly, for automatically supplying separator;Self-cleaning cutting mechanism, including cutting seat, cutting knife and negative pressure suction assembly;Cutting seat is formed with the cutting area for the passage of separator, cutting seat inside is equipped with cavity, cavity has the suction hole with opening towards cutting area.This application removes debris by negative pressure when cutting, cutting knife automatically scrapes suction hole by back-off, reduces the adhesion of debris from the source, improves detection accuracy;Cutting knife has cutting and self-cleaning function, simplify structure, reduce maintenance cost;Realize unwinding, cutting, conveying, detection, classification whole-process automation, improve efficiency, adapt to large-scale online detection;Work in thermostat, cooperate with air pressure control and surface defect detection, reduce environmental interference, improve result stability.

Description

Technical Field

[0001] This invention relates to the field of air permeability testing devices, and more specifically, to a fully automatic air permeability testing device and method for lithium-ion battery separators. Background Technology

[0002] The separator in a lithium-ion battery, located between the positive and negative electrodes, serves as both a channel for ion migration and an electronic insulating layer to prevent short circuits. Its microstructure directly determines the battery's polarization, rate performance, and safety margins. With the energy density of power batteries approaching 300 Wh / kg... -1 In the above iterations, the membrane thickness has been reduced to 5-12µm, the porosity needs to be precisely controlled at 35-45%, and the air permeability tolerance has been tightened from the traditional ±20s / 100mL to ±10s / 100mL.

[0003] In the current lithium-ion battery separator process, the separator needs to be cut into multiple strips for subsequent testing. During the cutting process, debris is easily generated and adheres to the surface of the strips, which affects the accuracy of the subsequent test results. Summary of the Invention

[0004] This invention provides a fully automated air permeability testing device and method for lithium-ion battery separators, solving the technical problem in related technologies where debris easily adheres to the surface of the sample strip during the cutting process, thus affecting the accuracy of subsequent test results.

[0005] This invention provides a fully automatic air permeability testing device for lithium-ion battery separators, including a constant temperature chamber, characterized in that the constant temperature chamber is equipped with: Diaphragm unwinding assembly for automatic diaphragm supply; The self-cleaning cutting mechanism includes a cutting seat, a cutter, and a negative pressure suction assembly; The cutting seat has a cutting area for the diaphragm to pass through, and the cutting seat has a cavity inside with a suction hole that opens towards the cutting area; the cutter is movably disposed in the cavity and can extend out of the cavity to automatically cut the diaphragm. The negative pressure suction component is connected to the suction hole and is used to automatically suck up waste during the cutting process; as the cutter retracts into the cavity after cutting, it scrapes and cleans the suction hole. An air permeability testing facility is used to automatically test the air permeability of cut strips.

[0006] As a further optimization of the present invention, the constant temperature chamber is also equipped with a tension control roller, a negative pressure adsorption belt and a rotating roller, which are used to automatically guide the diaphragm from the diaphragm unwinding assembly to the self-cleaning cutting mechanism.

[0007] As a further optimization of the present invention, a traction mechanism is also provided inside the constant temperature chamber to transport the cut strip from the self-cleaning cutting mechanism to the air permeability testing mechanism.

[0008] As a further optimization of the present invention, the cutting seat is a sleeve structure. The sleeve is horizontally installed inside the constant temperature chamber. The top of the sleeve forms a V-shaped space to constitute the cutting area. A central tube is fixedly installed in the middle of the sleeve. The cavity is located below the V-shaped space. One end of the sleeve is connected to the negative pressure suction component through a connecting tube.

[0009] As a further optimization of the present invention, the self-cleaning cutting mechanism also includes a push rod and a linear actuator. The push rod is fixedly connected to the cutter, and the linear actuator drives the cutter to move through the push rod.

[0010] As a further optimization of the present invention, the self-cleaning cutting mechanism also includes pads, which are installed on both sides of the top of the cutting seat to support the diaphragm.

[0011] As a further optimization of the present invention, the traction mechanism includes a linear module, a drive motor, a connecting plate, and suction cups. The output end of the linear module is fixedly connected to the drive motor, and the drive end of the drive motor is fixedly connected to the suction cups through the connecting plate. There are multiple suction cups, which are evenly distributed along the length direction of the connecting plate.

[0012] As a further optimization of the present invention, the air permeability detection mechanism includes a linear actuator, a mounting plate, a housing, a bottom shell, an air supply pipe, and a pressure sensor. The linear actuator is assembled inside the constant temperature chamber, and its driving end is connected to multiple housings through the mounting plate. One end of the air supply pipe is connected to the housing. The number of bottom shells corresponds to the number of housings, and it is located below the housings and connected to the inner wall of the constant temperature chamber through an assembly frame.

[0013] As a further optimization of the present invention, the constant temperature chamber is also equipped with a gripping mechanism and a storage box. The gripping mechanism is used to automatically place the sample strips after being tested by the air permeability testing mechanism into the corresponding storage boxes according to the test results.

[0014] As a further optimization of the present invention, the gripping mechanism includes a robotic arm and a suction nozzle, wherein the output end of the robotic arm is connected to the suction nozzle.

[0015] As a further optimization of the present invention, the constant temperature chamber is connected to an air inlet valve and an air outlet valve, and a pressure sensor is installed inside the constant temperature chamber.

[0016] As a further optimization of the present invention, two symmetrically arranged line array cameras are installed on the inner top of the constant temperature chamber. Both line array cameras are set at a 45-degree angle and are used to automatically detect defects on the diaphragm surface.

[0017] A fully automated method for detecting the air permeability of a lithium-ion battery separator, using the aforementioned apparatus, includes the following steps: The diaphragm unwinding assembly unwinds the diaphragm; The self-cleaning cutting mechanism uses a cutter to cut the diaphragm and automatically sucks up waste during the cutting process using a negative pressure suction component. When the cutter retracts, it scrapes and cleans the suction hole while sealing the suction hole to form a strip. The traction mechanism transports the sample to the air permeability testing mechanism; The air permeability testing agency conducts air permeability performance tests on the sample strips; The sampling mechanism classifies and collects the splines.

[0018] The beneficial effects of this invention are as follows: 1. In this invention, debris is removed in real time during the cutting process by a negative pressure suction component, and the suction hole is automatically blocked when the cutter retracts, thereby reducing the adhesion of debris to the sample surface from the source, reducing the interference of debris on the air permeability test results, and improving the accuracy and reliability of the test data.

[0019] 2. In this invention, the cutter has both cutting and self-cleaning functions. After cutting, it can retract to complete the scraping and cleaning of the suction hole, eliminating the need for additional cleaning equipment, simplifying the device structure and reducing maintenance costs.

[0020] 3. This invention automates the entire process from membrane unwinding, automatic cutting, sample transport, air permeability testing to classification and collection, without requiring manual intervention, thus improving testing efficiency and meeting the online testing needs of large-scale lithium battery membrane production.

[0021] 4. In this invention, the entire testing process is carried out in a constant temperature chamber. Combined with air pressure control and linear array camera defect detection, the interference of environmental and material factors such as temperature, air pressure, and diaphragm surface defects is reduced, further ensuring the stability of the test results. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of a fully automatic air permeability testing device for lithium-ion battery separators proposed in this invention.

[0023] Figure 2 This is a schematic diagram of the self-cleaning and cutting mechanism in a fully automatic air permeability testing device for lithium-ion battery separators proposed in this invention.

[0024] Figure 3 This is a schematic diagram of the air permeability detection mechanism in a fully automatic air permeability detection device for lithium-ion battery separators proposed in this invention.

[0025] Figure 4 This is a side view of the mounting plate in a fully automatic air permeability testing device for lithium-ion battery separators proposed in this invention.

[0026] In the picture: 1. Incubator; 2. Diaphragm unwinding assembly; 3. Tension control roller; 4. Negative pressure adsorption conveyor belt; 5. Rotary roller; 6. Self-cleaning cutting mechanism; 61. Sleeve; 611. Accommodation space; 612. Suction hole; 62. Central tube; 63. Connecting tube; 64. Cutter; 65. Push rod; 66. Linear actuator; 67. Pad plate; 7. Traction mechanism; 71. Linear module; 72. Drive motor; 73. Connecting plate; 74. Suction cup; 8. Air permeability detection mechanism; 81. Linear actuator; 82. Mounting plate; 83. Housing; 84. Bottom housing; 85. Air supply pipe; 86. Pressure sensor; 9. Gripping mechanism; 91. Robotic arm; 92. Suction nozzle; 10. Storage box; 11. Diaphragm; 12. Intake valve; 13. Exhaust valve; 14. Line scan camera; 15. Rotating roller. Detailed Implementation

[0027] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, features described in some examples may be combined in other examples.

[0028] Example 1 like Figures 1 to 4 As shown in the figure, an automatic air permeability testing device for lithium-ion battery separators according to an embodiment of the present invention includes a constant temperature chamber 1. The interior of the constant temperature chamber 1 is arranged sequentially from one side to the other as follows: separator unwinding assembly 2, tension control roller 3, negative pressure adsorption belt 4, rotating roller 5, self-cleaning cutting mechanism 6, traction mechanism 7, air permeability testing mechanism 8, gripping mechanism 9, and storage box 10.

[0029] The diaphragm unwinding assembly 2 loosens the diaphragm 11. The movable side of the diaphragm 11 passes sequentially through the tension control roller 3, the negative pressure adsorption belt 4, and the rotating roller 5. It is then cut into strips to be measured by the self-cleaning cutting mechanism 6 and adsorbed by the traction mechanism 7. The strips are then transported to the air permeability testing mechanism 8 for multi-point testing. The gripping mechanism 9 separates the unqualified and qualified strips into the corresponding storage boxes 10. The storage boxes 10 are divided into qualified and unqualified boxes.

[0030] The self-cleaning cutting mechanism 6 includes a cutting seat and a cutting component.

[0031] In a preferred embodiment, the cutting seat is a sleeve 61 structure, which is horizontally installed inside the constant temperature chamber 1. The top of the sleeve 61 forms a V-shaped space to constitute the cutting area. A central tube 62 is fixedly fitted in the middle of the sleeve 61. The top of the sleeve 61, located below the V-shaped space, connects to a cavity (accommodating space 611). The sleeve 61 has a suction hole 612 at the accommodating space 611 to collect the waste generated by the diaphragm 11 as it is cut. One end of the sleeve 61 is connected to the negative pressure suction assembly through a connecting pipe 63. When the negative pressure suction assembly extracts, the diaphragm 11 passes above the V-shaped space to collect the waste generated by cutting, reducing the adhesion of impurities to the sample strip and thus improving the accuracy of subsequent test results.

[0032] The cutting components include a cutter 64, a push rod 65, and a linear actuator 66. Preferably, the linear actuator 66 is an electric push rod or a cylinder. The cutter 64 is slidably sleeved inside the receiving space 611. When not cutting, the cutter 64 enters the receiving space 611 to scrape and clean the suction hole 612, while simultaneously sealing the suction hole 612. The push rod 65 is slidably sleeved on the sleeve 61 and the central tube 62 in the vertical direction. One end of the push rod 65 slides into the receiving space 611 and is fixedly connected to the cutter 64. The other end of the push rod 65 is fixedly connected to the output end of the linear actuator 66, which is fixedly connected to the constant temperature chamber 1. When the linear actuator 66 is activated, the traction mechanism 7 acts as a push plate on the top of the diaphragm 11, driving the cutter 64 towards the diaphragm 11 via the push rod 65 to cut off the strip of the required size from the diaphragm 11. When the cutter 64 enters the receiving space 611 from the V-shaped space, it can also be sucked by the suction hole 612 for suction and cleaning, which is beneficial to cleanliness when used again.

[0033] As a further preferred embodiment, the self-cleaning cutting mechanism 6 also includes a pad 67, which is installed on both sides of the top of the sleeve 61 to support and place the diaphragm 11. At the same time, two rotating rollers 15 are rotatably arranged upstream of the pad 67, which are located above and below the diaphragm 11 respectively to limit the position of the slit diaphragm 11.

[0034] The traction mechanism 7 includes a linear module 71, a drive motor 72, a connecting plate 73, and suction cups 74. The output end of the linear module 71 is fixedly connected to the drive motor 72, and the drive end of the drive motor 72 is fixedly connected to the suction cups 74 via the connecting plate 73. Preferably, there are multiple suction cups 74, which are evenly distributed along the length of the connecting plate 73 to adsorb the sample strip and place it at the detection point of the subsequent air permeability testing mechanism 8. The connecting plate 73 can act as a holding plate when the cutter 64 cuts the diaphragm 11. The linear module 71 drives the diaphragm 11 to move horizontally, and the drive motor 72 drives the diaphragm 11 to rotate 180 degrees to place the diaphragm at the detection point of the air permeability testing mechanism 8.

[0035] When the traction mechanism 7 moves back, it will pull the diaphragm 11 onto the pad 67 and cut it by the cutter 64. Then, the suction cup 74 will adsorb the strip formed by the cut.

[0036] The air permeability testing mechanism 8 includes a linear actuator 81, a mounting plate 82, housings 83, a bottom shell 84, an air supply pipe 85, and a pressure sensor 86. The linear actuator 81 is a hydraulic cylinder, an electric actuator, or a pneumatic cylinder. The linear actuator 81 is mounted inside the constant temperature chamber 1, and its drive end is connected to multiple housings 83 via the mounting plate 82. One end of the air supply pipe 85 is connected to a housing 83 to inflate it, and the other end is used to introduce gas. The number of bottom shells 84 corresponds to the number of housings 83, and they are located below the housings 83 and connected to the inner wall of the constant temperature chamber 1 via a mounting bracket. When the sample is placed on top of the multiple bottom shells 84, the linear actuator 81 moves the housings 83 downwards to press against the diaphragm 11. At this time, gas is introduced into the housings 83, and the pressure sensor 86 detects the pressure change inside the housings 83 to determine the air permeability.

[0037] The gripping mechanism 9 includes a robotic arm 91 and a suction nozzle 92. The output end of the robotic arm 91 is connected to the suction nozzle 92 to grip the tested sample and place it into the corresponding storage box 10.

[0038] Example 2 Based on Embodiment 1, in order to maintain constant temperature and air pressure and reduce the impact of the environment on the test results, the constant temperature chamber 1 is connected to an air inlet valve 12 and an air outlet valve 13. The air inlet valve 12 is connected to an air supply device to maintain the internal pressure of the constant temperature chamber 1. Preferably, the constant temperature chamber 1 is equipped with an air pressure sensor to detect the internal environmental pressure.

[0039] Example 3 Based on Embodiment 2, as a further preferred embodiment, two symmetrically arranged line array cameras 14 are installed on the top of the constant temperature chamber 1. Both line array cameras 14 are set at a 45-degree angle to effectively avoid interference from reflections on the diaphragm surface and to photograph and detect defects on the diaphragm 11 surface; they can identify pinholes, creases, etc., reducing the impact on the accuracy of the detection results.

[0040] Example 4 A fully automated method for detecting the air permeability of a lithium-ion battery separator, using the aforementioned apparatus, includes the following steps: The diaphragm unwinding assembly 2 unwinds the diaphragm 11; The self-cleaning cutting mechanism 6 uses a cutter 64 to cut the diaphragm 11 and automatically sucks up waste during the cutting process through a negative pressure suction component. When the cutter 64 retracts, it scrapes and cleans the suction hole 612 while sealing the suction hole 612 to form a strip. The traction mechanism 7 transports the sample to the air permeability testing mechanism 8; The air permeability testing agency conducted air permeability tests on 8 pairs of sample strips. The grabbing mechanism collects 9 pairs of splines by classification.

[0041] The embodiments of the present invention have been described above, but the embodiments are not limited to the specific implementation methods described above. The specific implementation methods described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the embodiments described above, all of which are within the protection scope of the embodiments described above.

Claims

1. A fully automatic air permeability testing device for lithium-ion battery separators, comprising a constant temperature chamber (1), characterized in that, The constant temperature chamber (1) is equipped with: Diaphragm unwinding assembly (2) for automatically supplying diaphragm (11); The self-cleaning cutting mechanism (6) includes a cutting seat, a cutter (64), and a negative pressure suction assembly; A cutting area is formed on the cutting seat for the diaphragm (11) to pass through. The cutting seat is provided with a cavity, which has a suction hole (612) with an opening facing the cutting area. The cutter (64) is movably disposed in the cavity and can extend out of the cavity to automatically cut the diaphragm (11). The negative pressure suction component is connected to the suction hole (612) and is used to automatically suck up waste during the cutting process; the cutter (64) scrapes and cleans the suction hole (612) during the process of retracting back to the cavity after cutting. The air permeability testing mechanism (8) is used to automatically test the air permeability of the cut strips.

2. The fully automatic air permeability detection device for lithium-ion battery separators according to claim 1, characterized in that: The constant temperature chamber (1) is also equipped with a tension control roller (3), a negative pressure adsorption belt (4) and a rotating roller (5) to automatically guide the diaphragm (11) from the diaphragm unwinding assembly (2) to the self-cleaning cutting mechanism (6).

3. The fully automatic air permeability detection device for lithium-ion battery separators according to claim 1, characterized in that: The constant temperature chamber (1) is also equipped with a traction mechanism (7) for transporting the cut strips from the self-cleaning cutting mechanism (6) to the air permeability testing mechanism (8).

4. The fully automatic air permeability detection device for lithium-ion battery separators according to claim 1, characterized in that: The cutting seat is a sleeve (61) structure. The sleeve (61) is horizontally installed inside the constant temperature chamber (1). The top of the sleeve (61) forms a V-shaped space to constitute the cutting area. A central tube (62) is fixedly installed in the middle of the sleeve (61). The cavity is located below the V-shaped space. One end of the sleeve (61) is connected to the negative pressure suction assembly through a connecting tube (63).

5. The fully automatic air permeability detection device for lithium-ion battery separators according to claim 1, characterized in that: The self-cleaning cutting mechanism (6) also includes a push rod (65) and a linear actuator (66). The push rod (65) is fixedly connected to the cutter (64), and the linear actuator (66) drives the cutter (64) to move through the push rod (65).

6. The fully automatic air permeability detection device for lithium-ion battery separators according to claim 1, characterized in that: The self-cleaning cutting mechanism (6) also includes pads (67) mounted on both sides of the top of the cutting seat for supporting the diaphragm (11).

7. The fully automatic air permeability detection device for lithium-ion battery separators according to claim 3, characterized in that: The traction mechanism (7) includes a linear module (71), a drive motor (72), a connecting plate (73), and a suction cup (74). The output end of the linear module (71) is fixedly connected to the drive motor (72), and the drive end of the drive motor (72) is fixedly connected to the suction cup (74) through the connecting plate (73). There are multiple suction cups (74), which are evenly distributed along the length direction of the connecting plate (73).

8. The fully automatic air permeability detection device for lithium-ion battery separators according to claim 1, characterized in that: The air permeability testing mechanism (8) includes a linear actuator (81), a mounting plate (82), a housing (83), a bottom shell (84), an air supply pipe (85), and a pressure sensor (86). The linear actuator (81) is installed inside the constant temperature chamber (1). Its drive end is connected to multiple housings (83) through the mounting plate (82). One end of the air supply pipe (85) is connected to the housing (83). The number of bottom shells (84) corresponds to the number of housings (83). They are located below the housings (83) and connected to the inner wall of the constant temperature chamber (1) through the mounting bracket.

9. The fully automatic air permeability detection device for lithium-ion battery separators according to claim 1, characterized in that: The constant temperature chamber (1) is also equipped with a gripping mechanism (9) and a storage box (10). The gripping mechanism (9) is used to automatically put the sample strips after being tested by the air permeability testing mechanism (8) into the corresponding storage box (10) according to the test results.

10. A fully automated air permeability testing method for lithium-ion battery separators, employing the fully automated air permeability testing device for lithium-ion battery separators as described in any one of claims 1 to 9, characterized in that, Includes the following steps: The diaphragm unwinding assembly (2) unwinds the diaphragm (11); The self-cleaning cutting mechanism (6) uses a cutter (64) to cut the diaphragm (11) and automatically sucks up the waste through the negative pressure suction component during the cutting process. When the cutter (64) retracts, it scrapes and cleans the suction hole (612) while sealing the suction hole (612) to form a strip. The traction mechanism (7) transports the sample to the air permeability testing mechanism (8); The air permeability testing agency (8) conducts air permeability tests on the sample strips; The grabbing mechanism (9) classifies and collects the splines.

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