Helium detection device for battery pack upper cover made of composite material

Abstract

The utility model belongs to the technical field of automobile part detection equipment, and provides a helium detection device for a composite material battery pack upper cover, which comprises a detection box body, a pressing frame body, a first pressing device, a second pressing device, a gas circulation device, a blower device, a helium mass spectrometer leak detector and a box body sealing door. A special tool design is carried out on the sealing performance of the battery pack upper cover made of a composite material of a power battery, specifically, aiming at the problem that the battery pack upper cover is thin in wall thickness and can generate expansion deformation after being inflated, the structure of the pressing frame body, the first pressing device and the second pressing device is arranged to reduce the deformation quantity of the battery pack upper cover after being inflated, and the detection precision is improved.

Description

Technical Field

[0001] This utility model belongs to the technical field of automotive component testing equipment, specifically relating to a helium detection device for a composite material battery pack cover. Background Technology

[0002] As a core component of new energy vehicles, the airtightness, dustproofing, and waterproofing performance of power batteries are crucial to the safety of the entire vehicle, directly impacting its overall safety. Leaks can lead to numerous problems such as electrolyte evaporation, moisture penetration, and swelling, resulting in decreased battery performance and even fire or explosion. The sealing performance of the battery casing directly determines the battery's safety factor; therefore, improving the accuracy and efficiency of battery pack leak detection is of paramount importance.

[0003] There are many battery assembly processes, such as winding, hot pressing, X-ray inspection, tab over-soldering, welding, electrolyte injection, sealing, wrapping, and module assembly. Among these, electrolyte leakage detection and overall pack airtightness testing directly determine the battery's safety performance, and leakage detection is an essential step in ensuring battery safety.

[0004] Battery packs are typically encased in a casing. This casing must generally meet IP67 (or higher) water protection standards, with a leakage rate within the range of 5*10⁻³ mbar l / s. A typical power battery cell consists of a positive electrode, a negative electrode, a separator, and its electrolyte. These cells are arranged within the packaging. Due to the highly reactive chemical properties of lithium metal, its production, processing, storage, and application require extremely high environmental standards. Leak detection is crucial at the welded joints of the lithium battery casing. If the electrolyte leaks due to an unsealed casing, it can react violently with a humid environment, causing serious harm to the environment and workers, and affecting the lifespan of equipment. Therefore, leak detection is essential at critical stages of battery assembly and sealing (cylindrical and prismatic cells are welded). Depending on the manufacturing process, a helium mass spectrometer leak detector or a helium leak detection system can be selected. In terms of sealing performance testing, using helium detection instead of traditional gas detection can significantly improve leak detection efficiency and precision. However, there is currently no mature solution in China for helium testing of composite material covers for power batteries. The wall thickness of the composite material cover is 1.2mm, which is thin. After inflation, it will expand and deform, affecting the accuracy of airtightness testing. Utility Model Content

[0005] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of this utility model is to provide a helium detection device for a battery pack cover made of composite materials.

[0006] The technical solution adopted by this utility model to solve its technical problem is:

[0007] A helium detection device for a battery pack cover made of composite material includes a detection box, a pressure frame, a first pressing device, a second pressing device, a gas circulation device, a blower, a helium mass spectrometer leak detector, and a box sealing door.

[0008] The testing chamber includes a cavity for placing the battery pack cover. The chamber sealing door is located at the cavity opening. The pressure frame, the first pressure device, the second pressure device, and the blower are located inside the cavity. The first pressure device is located above the pressure frame, and the second pressure device corresponds to the position where the battery pack cover is placed.

[0009] The gas circulation device includes an extraction device, a helium supply device, an extraction pipeline, and a supply pipeline. The extraction end of the extraction device is connected to the extraction pipeline, and one end of the extraction pipeline corresponds to the position where the battery pack cover is placed. The supply end of the helium supply device is connected to the supply pipeline, and one end of the supply pipeline corresponds to the position where the battery pack cover is placed.

[0010] The detection end of the helium mass spectrometer leak detector is located inside the cavity of the detection chamber.

[0011] Preferably, the first pressing device includes a first pressing cylinder component, and a sealing plug is provided on the cylinder rod component of the first pressing cylinder component.

[0012] Preferably, the second pressing device includes a second pressing cylinder, and the cylinder rod of the second pressing cylinder is provided with a pressing head.

[0013] Preferably, the pressure frame is a frame structure, and the frame of the pressure frame is provided with a plurality of clearance holes;

[0014] When the pressure frame body contacts the battery pack cover, the position of the clearance hole corresponds to the position of the first pressing device;

[0015] The second clamping device is located around the pressure frame.

[0016] Preferably, the shape of the vent hole is square.

[0017] Preferably, one end of the pressure frame is hinged to the inner wall of the cavity of the detection box.

[0018] Preferably, the testing chamber is provided with an air circulation pipe, the two ends of which are connected to the cavity of the testing chamber and correspond to the position where the battery pack cover is placed;

[0019] One end of the air extraction pipe is connected to the air circulation pipe, and one end of the air supply pipe is connected to the air circulation pipe.

[0020] Preferably, an exhaust valve is provided at the connection between the exhaust end of the exhaust device and the exhaust pipeline, and an inlet valve is provided at the connection between the supply end of the helium supply device and the supply pipeline.

[0021] Preferably, the bottom of the cavity of the battery pack cover is provided with a support seat, and the support seat is positioned corresponding to the position of the first pressing device.

[0022] Compared with the prior art, the beneficial effects of this utility model include:

[0023] The helium detection device of this application has a proprietary tooling design for the sealing of the battery pack cover made of composite materials for power batteries. Specifically, in response to the problem that the wall thickness is thin and that expansion deformation will occur after inflation, a structure of a pressure frame, a first pressing device, and a second pressing device is set up to reduce the deformation of the battery pack cover after inflation and improve the accuracy of detection. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of the present invention after the battery pack cover is installed.

[0026] Figure 2 This is a perspective view of the present invention.

[0027] Figure 3 This is a simplified cross-sectional view of the internal structure of the detection box of this utility model.

[0028] in:

[0029] 1-Detection chamber, 101-Cavity, 2-Pressure frame, 201-Void hole, 3-First pressing device, 4-Second pressing device, 5-Blower, 6-Helium mass spectrometer leak detector, 7-Sealed door of the chamber, 8-Evacuation device, 9-Helium supply device, 10-Evacuation pipeline, 11-Supply pipeline, 12-Support base, 13-Battery pack cover, 14-Air circulation pipeline. Detailed Implementation

[0030] To better understand the above-mentioned objectives, features, and advantages of this utility model, it will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. Many specific details are set forth in the following description to provide a thorough understanding of this utility model; the described embodiments are merely some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0032] Example:

[0033] like Figure 1-3 As shown, this embodiment provides a helium detection device for a battery pack cover made of composite material, including a detection box 1, a pressure frame 2, a first pressing device 3, a second pressing device 4, a gas circulation device, a blower 5, a helium mass spectrometer leak detector 6, and a box sealing door 7.

[0034] The test chamber 1 includes a cavity 101 for placing the battery pack cover 1313. The chamber sealing door 7 is located at the opening of the cavity 101. The pressure frame 2, the first pressing device 3, the second pressing device 4, and the blower 5 are located inside the cavity 101. The first pressing device 3 is located above the pressure frame 2, and the second pressing device 4 corresponds to the position where the battery pack cover 13 is placed.

[0035] The gas circulation device includes an extraction device 8, a helium supply device 9, an extraction pipeline 10, and a supply pipeline 11. The extraction end of the extraction device 8 is connected to the extraction pipeline 10, and one end of the extraction pipeline 10 corresponds to the position where the battery pack cover 13 is placed. The supply end of the helium supply device 9 is connected to the supply pipeline 11, and one end of the supply pipeline 11 corresponds to the position where the battery pack cover 13 is placed.

[0036] The detection end of the helium mass spectrometer leak detector 6 is located inside the cavity 101 of the detection chamber 1.

[0037] The helium detection device in this embodiment employs a proprietary tooling design for the sealing of the composite material battery pack cover 13 of the power battery. Specifically, addressing the issue of its thin wall thickness and expansion deformation after inflation, a structure consisting of a pressure frame 2, a first pressing device 3, and a second pressing device 4 is incorporated to reduce the deformation of the battery pack cover 13 after inflation, thereby improving detection accuracy. The detection principle of this embodiment is as follows:

[0038] Place the battery pack cover 13 into the cavity 101 of the testing chamber 1, bring the pressure frame 2 into contact with the battery pack cover 13, press the flange edge of the battery pack cover 13 with the first pressing device 3, press the battery pack cover 13 with the second pressing device 4, close the chamber sealing door 7 and seal the cavity 101 of the testing chamber 1. After the above actions are completed, first use the vacuum device 8 to evacuate the cavity 101 of the battery pack cover 13 to achieve the required vacuum state, and then use the helium supply device 9 to fill it with helium to ensure that the battery pack cover 13 is in a vacuum state. The helium concentration inside cavity 101 meets the testing requirements; the cavity 101 of the testing chamber 1 is kept sealed by the sealing door 7, and the helium leaking from the battery pack cover 13 remains inside cavity 101 of the testing chamber 1. Under the action of the blower, it continuously mixes and circulates inside cavity 101 of the testing chamber 1 and will not escape outside the chamber; during the testing time, the helium mass spectrometer leak detector 6 detects the helium concentration of the mixed gas; after the test is completed, the helium inside cavity 101 of battery pack cover 13 is transferred away by the extraction device 8.

[0039] The function of the blower mentioned above is to fully mix the leaked helium gas with the air in the cavity 101 of the detection box 1. The helium mass spectrometer leak detector 6 is used to detect the helium concentration of the mixed gas to determine the amount of leakage.

[0040] The first pressing device 3 in this embodiment includes a first pressing cylinder component. The cylinder rod of the first pressing cylinder component is provided with a sealing plug, which is used to seal the assembly surface of the battery pack cover 13.

[0041] The second clamping device 4 in this embodiment includes a second clamping cylinder, and a pressure head is provided on the cylinder rod of the second clamping cylinder. Its function is to act on the clamping frame 2 to ensure the stability of the contact between the clamping frame 2 and the battery pack cover 13, prevent shaking when evacuating or sucking air from the battery pack cover 13, and improve the accuracy of detection.

[0042] In this embodiment, the pressure frame 2 is a frame structure, and the frame of the pressure frame 2 is provided with a plurality of clearance holes 201;

[0043] When the pressure frame 2 contacts the battery pack cover 13, the position of the clearance hole 201 corresponds to the position of the first pressing cylinder component;

[0044] The second clamping device 4 is located around the clamping frame 2.

[0045] Specifically, the vent hole 201 is square in shape.

[0046] The above structure has several advantages. First, the clearance hole 201 can reduce the overall weight of the pressure frame 2 and prevent the pressure frame 2 from exerting excessive force on the battery pack cover 13, which would cause deformation and affect the accuracy of the test. Second, the clearance hole 201 is positioned to correspond to the position of the first pressing cylinder component, which avoids interference between the pressure frame 2 and the first pressing cylinder component when they come into contact with the battery pack cover 13.

[0047] In order to facilitate the contact or release of the pressure frame 2 with the battery pack cover 13, one end of the pressure frame 2 is hinged to the inner wall of the cavity 101 of the detection box 1, and the above operation is achieved by flipping the pressure frame 2.

[0048] The detection chamber 1 in this embodiment is also provided with an air circulation pipe 14. The two ends of the air circulation pipe 14 are connected to the cavity 101 of the detection chamber 1 and correspond to the position of the battery pack cover 13.

[0049] One end of the exhaust pipe 10 is connected to the air circulation pipe 14, and one end of the air supply pipe 11 is connected to the air circulation pipe 14.

[0050] Specifically, an exhaust valve is provided at the connection between the exhaust end of the exhaust device 8 and the exhaust pipe 10, and an inlet valve is provided at the connection between the supply end of the helium supply device 9 and the supply pipe 11.

[0051] Specifically, a support seat 12 is provided at the bottom of the cavity 101 of the battery pack cover 13. The support seat 12 is positioned corresponding to the first pressing device 3 and is used to support the battery pack cover 13.

[0052] The detection method in this embodiment has the following steps:

[0053] S1. Place the battery pack cover 13 into the test chamber 1 and fix it by the pressure frame 2, the first pressing device 3, and the second pressing device 4, and then close the chamber sealing door 7.

[0054] S2. Open the exhaust valve and use the vacuum pump 8 to evacuate the inner cavity of the battery pack cover 13. After completion, use the helium supply device 9 to fill the battery with helium until the set pressure is reached and then stop.

[0055] S3. Close the exhaust valve and the intake valve, and use the blower 5 to circulate the air in the cavity 101 of the detection chamber 1.

[0056] S4. The detection time starts, and the helium mass spectrometer leak detector 6 starts to detect the helium concentration of the air in the detection chamber 1. If the helium concentration exceeds the standard within the detection time, it is judged as NG; otherwise, it is judged as OK.

[0057] S5. After the test is completed, release the fixing of the battery pack cover 13 by the pressure frame 2, the first pressing device 3, and the second pressing device 4, open the exhaust valve and the air inlet valve, and then use the air extraction device 8 to remove helium. After the helium value of the cavity 101 of the test box 1 returns to zero, the next test can be carried out.

[0058] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A helium detection device for a battery pack cover made of composite materials, characterized in that, include: The test chamber includes the pressure frame, the first pressing device, the second pressing device, the gas circulation device, the blower, the helium mass spectrometer leak detector, and the chamber's sealing door. The testing chamber includes a cavity for placing the battery pack cover. The chamber sealing door is located at the cavity opening. The pressure frame, the first pressure device, the second pressure device, and the blower are located inside the cavity. The first pressure device is located above the pressure frame, and the second pressure device corresponds to the position where the battery pack cover is placed. The gas circulation device includes an extraction device, a helium supply device, an extraction pipeline, and a supply pipeline. The extraction end of the extraction device is connected to the extraction pipeline, and one end of the extraction pipeline corresponds to the position where the battery pack cover is placed. The supply end of the helium supply device is connected to the supply pipeline, and one end of the supply pipeline corresponds to the position where the battery pack cover is placed. The detection end of the helium mass spectrometer leak detector is located inside the cavity of the detection chamber.

2. The helium detection device for the battery pack cover of the composite material according to claim 1, characterized in that, The first clamping device includes a first clamping cylinder component, and a sealing plug is provided on the cylinder rod component of the first clamping cylinder component.

3. The helium detection device for the battery pack cover of the composite material according to claim 1, characterized in that, The second clamping device includes a second clamping cylinder component, and a pressure head component is provided on the cylinder rod component of the second clamping cylinder component.

4. The helium detection device for the battery pack cover of the composite material according to claim 1, characterized in that, The pressure frame is a frame structure, and the frame of the pressure frame is provided with a number of clearance holes; When the pressure frame body contacts the battery pack cover, the position of the clearance hole corresponds to the position of the first pressing device; The second clamping device is located around the pressure frame.

5. The helium detection device for the battery pack cover of the composite material according to claim 4, characterized in that, The vent hole is square in shape.

6. The helium detection device for the battery pack cover of the composite material according to claim 1, characterized in that, One end of the pressure frame is hinged to the inner wall of the cavity of the detection box.

7. The helium detection device for the battery pack cover of the composite material according to claim 1, characterized in that, The testing chamber is equipped with an air circulation pipe, the two ends of which are connected to the cavity of the testing chamber and correspond to the position where the battery pack cover is placed. One end of the air extraction pipe is connected to the air circulation pipe, and one end of the air supply pipe is connected to the air circulation pipe.

8. The helium detection device for the battery pack cover of the composite material according to claim 7, characterized in that, An exhaust valve is provided at the connection between the exhaust end of the exhaust device and the exhaust pipeline, and an inlet valve is provided at the connection between the supply end of the helium supply device and the supply pipeline.

9. The helium detection device for the battery pack cover of the composite material according to claim 1, characterized in that, The bottom of the cavity of the battery pack cover is provided with a support base, which is positioned corresponding to the position of the first pressing device.

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