Cylindrical battery assembly pressure testing device

Abstract

The utility model discloses a pressure testing device for a cylindrical battery assembly. The pressure testing device comprises a base station, at least one cylindrical battery assembly limiting boss arranged on the upper surface of the base station, and a pressing unit matched with the cylindrical battery assembly limiting boss, a test water flow channel communicated with the bottom of the cylindrical battery assembly limiting boss is arranged in the base station, and the outer side of the base station is connected with a test water path system communicated with the test water flow channel. The pressure testing device for the cylindrical battery assembly can perform explosion-proof pressure testing on a cathode cover plate and / or an anode column of a cylindrical lithium ion battery through water pressure, is simple to operate, and can effectively solve the safety problem caused by air pressure testing.

Description

Technical Field

[0001] The utility model relates to the technical field of battery testing devices, in particular to a cylindrical battery assembly pressure testing device. Background Art

[0002] The two ends of the cylindrical battery are the positive column and the negative cover (also called the negative top cover), which are connected together by a cylindrical battery shell. When the lithium-ion battery is overcharged, over-discharged or short-circuited, its electrolyte components will decompose and release a large amount of heat and gas, causing the temperature and pressure inside the battery to rise rapidly, and then there is a risk of combustion and explosion. In order to prevent the battery from exploding directly, an explosion-proof valve is installed on the negative cover of the battery. When the temperature and pressure inside the battery are too high, the valve automatically opens to release gas, which plays a role in preventing the battery from exploding. The pressure resistance of the cylindrical battery shell is significantly greater than that of the two ends, and when an explosion occurs, there is a high probability that the pressure will be released from both ends. Therefore, it involves explosion-proof pressure testing of the negative cover and the positive column. The pressure requirements vary according to the process, but the pressure resistance of the positive column must be greater than that of the negative cover to ensure the explosion-proof effect of the explosion-proof valve.

[0003] The withstand voltage test is the main method to test the overvoltage resistance of electrical appliances, electrical equipment, electrical devices, electrical circuits and electrical safety equipment. It is particularly important to monitor the withstand voltage of lithium batteries during the production process. Poor withstand voltage will affect the performance of lithium batteries, and excessive withstand voltage will bring potential explosion risks. In order to ensure the qualified rate of battery production, withstand voltage test tooling equipment is generally used to test the negative electrode cover and positive electrode column. On the one hand, the negative electrode cover and positive electrode column of the battery are sampled and tested before they are welded to the battery shell to confirm that their quality meets the standards. On the other hand, pressure testing is performed when the battery is damaged for failure analysis.

[0004] CN210719657U discloses a battery top cover pressure test device, including a base, a battery seat is provided on the upper surface of the base, a through hole is provided on the bottom plate of the battery seat, and a gas pipe is sleeved on the through hole, which acts on the battery top cover through gas pressure to complete the pressure test of the battery top cover. The device performs explosion-proof pressure test on the battery top cover through gas pressure, which requires a high-pressure external gas source, and there is a certain risk. In addition, the pressure on the battery top cover rises rapidly when the gas is input, and the pressure measured at the critical point of explosion is inaccurate. Utility Model Content

[0005] The purpose of the utility model is to overcome the shortcomings and defects of the prior art and to provide a cylindrical battery assembly pressure testing device, which can simultaneously perform explosion-proof pressure testing of the negative electrode cover and the positive electrode column of the cylindrical battery through water pressure.

[0006] A cylindrical battery assembly pressure testing device comprises a base, at least one cylindrical battery assembly limiting boss arranged on the upper surface of the base, and a clamping unit matched with the cylindrical battery assembly limiting boss; a test water flow channel connected to the bottom of the cylindrical battery assembly limiting boss is arranged inside the base, and the outer side of the base is connected to a test water channel system connected to the test water flow channel.

[0007] Optionally, the cylindrical battery assembly includes a negative electrode cover plate and / or a positive electrode column.

[0008] Optionally, the cylindrical battery assembly includes a negative electrode cover and a positive electrode; the cylindrical battery assembly pressure testing device includes a base and at least one cover limiting boss and at least one pole limiting boss arranged on the upper surface of the base, and a cover clamping unit cooperating with the cover limiting boss and a pole clamping unit cooperating with the pole limiting boss; a test water flow channel communicating with the bottom of the cover limiting boss and the pole limiting boss is arranged inside the base, and the outer side of the base is connected to a test water channel system communicating with the test water flow channel.

[0009] Among them, the cover plate pressing unit includes a pressing block and a top cover; the pressing block is used to press on the cover plate to be tested after the cover plate to be tested is placed in the cover plate limiting hole of the cover plate limiting boss that is connected to the test water flow channel, and the top cover is used to press the pressing block on the cover plate to be tested after being connected to the cover plate limiting boss.

[0010] Wherein, the top cover has an internal thread, and the cover plate limiting boss has an external thread matching the internal thread; the top cover is threadedly connected to the cover plate limiting boss.

[0011] Wherein, the top of the top cover is provided with a water pipe joint, and the center of the pressing block is provided with a water hole.

[0012] Among them, the pole clamping unit includes a pressing ring and a fastener. The fastener is used to pass through the mounting hole on the outside of the pressing ring and threadedly connect with the threaded hole on the base after the positive pole to be tested is placed in the positive pole limiting hole of the pole limiting boss which is connected with the test water flow channel, so as to lock the pressing ring and press it on the upper end of the positive pole to be tested.

[0013] There are four mounting holes, which are evenly arranged on the outside of the pressure ring.

[0014] Among them, the test water system includes an inlet pipe and a return pipe, one end of the inlet pipe and the return pipe are connected to the water pipe interface of the diversion chamber, and the other end is connected to the water outlet on the side of the base; the diversion chamber has an external water source interface connected to the external test water source.

[0015] Wherein, the water inlet pipeline and the water return pipeline are respectively connected to the water pipe interface for water inlet and outlet of the diversion chamber through a connected gate valve.

[0016] Wherein, the water inlet pipeline and the water return pipeline are connected to the water outlet on the side of the base through a quick connector.

[0017] Wherein, a pressure gauge is arranged on the cavity body of the diversion cavity.

[0018] The cylindrical battery assembly pressure testing device of the utility model has a simple structure, can effectively test whether the pressure resistance of the cylindrical battery assembly meets the requirements, is easy to operate, and can effectively solve the safety problems caused by air pressure testing.

[0019] The cylindrical battery assembly pressure testing device of the utility model can simultaneously perform explosion-proof pressure tests on the negative electrode cover and the positive electrode column of a cylindrical lithium-ion battery through water pressure, has a unified test standard, and has accurate test results. It can also be judged through the test whether the explosion-proof pressure of the positive electrode column is greater than the explosion-proof pressure of the negative electrode cover, and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an exploded view of the cylindrical battery assembly pressure testing device of the present invention.

[0021] Figure 2 This is an axonometric view of the cylindrical battery assembly pressure testing device of the present invention.

[0022] Figure 3 It is a schematic diagram of the connection between the test water flow channel inside the base and the external test water system under the cross section.

[0023] Figure 4 This is a cross-sectional view of the negative electrode cover being pressed during the test.

[0024] Figure 5 yes Figure 4 A partial enlarged view of the .

[0025] Figure 6 This is a cross-sectional view of the positive pole when it is pressed for testing.

[0026] Figure 7 yes Figure 6 A partial enlarged view of the .

[0027] Description of reference numerals:

[0028] 1-fastener, 2-pressure ring, 3-base, 4-quick connector, 5-connecting pipe, 6-gate valve, 7-diverter chamber, 8-pressure gauge, 9-pressure block, 10-top cover, 11-water pipe connector, 31-pole limiting boss, 32-cover limiting boss, 33-test water flow channel, 34-limiting step, 71-external water source interface, 72-water pipe interface, 100-negative cover, 110-connector cavity, 200-positive pole. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] like Figures 1 to 7 As shown, a cylindrical battery assembly pressure testing device according to an embodiment of the utility model comprises a base and at least one cylindrical battery assembly limiting boss arranged on the upper surface of the base, and a clamping unit matched with the cylindrical battery assembly limiting boss; a test water flow channel 33 communicating with the bottom of the cylindrical battery assembly limiting boss is arranged inside the base, and the outer side of the base is connected to a test water channel system communicating with the test water flow channel 33.

[0031] In an optional embodiment, the cylindrical battery assembly includes a negative electrode cover plate and / or a positive electrode column, and a water pressure test can be performed on the negative electrode cover plate and / or the positive electrode column.

[0032] In one embodiment, the cylindrical battery assembly includes a negative cover plate and a positive column, and the negative cover plate and the positive column are tested at the same time; the cylindrical battery assembly pressure testing device includes a base and at least one cover plate limiting boss 32, at least one pole limiting boss 31, and a cover plate clamping unit matched with the cover plate limiting boss 32, and a pole limiting boss 31; a test water flow channel 33 connected to the bottom of the cover plate limiting boss 32 and the pole limiting boss 31 is arranged inside the base, and the outer side of the base is connected to a test water channel system connected to the test water flow channel 33.

[0033] In a preferred embodiment, the cover plate pressing unit includes a pressing block 9 and a top cover 10; the pressing block is used to press the cover plate 100 to be tested on the cover plate 100 after the negative cover plate 100 to be tested is placed in the cover plate limiting hole of the cover plate limiting boss 32 that communicates with the test water flow channel 33, and the top cover 10 is used to press the pressing block 9 on the negative cover plate to be tested after being connected to the cover plate limiting boss 32, see Figure 4 , Figure 5As shown, the cover plate limiting hole has a limiting step 34 for supporting and limiting the negative electrode cover plate, and the pressing block 9 has an annular pressing portion that cooperates with the limiting step 34. When the negative electrode cover plate is placed in the cover plate limiting hole, the outer side is limited and the bottom is supported on the plane of the limiting step. When the pressing block 9 is placed, it is pressed on the negative electrode cover plate 100 through its annular pressing portion, and cooperates with the bottom plane of the limiting step. Under the action of the top cover, the negative electrode cover plate 100 is pressed tightly, see Figure 4 , Figure 5 shown.

[0034] In order to facilitate the connection or disassembly of the top cover and the cover plate limiting boss, the top cover in the present application has an internal thread, and the cover plate limiting boss has an external thread matching the internal thread; the top cover and the cover plate limiting boss are threadedly connected.

[0035] Since there is an explosion-proof valve on the negative electrode cover 100 of the battery, it may rupture during pressure testing in general. Therefore, a water pipe connector 11 is provided on the top of the top cover 10 to connect a hose for water recovery. An avoidance groove structure is formed on the lower end surface of the pressing block 9 to separate and not contact the surface of the negative electrode cover to be tested, so as to ensure that the water pressure test is not affected. A water hole 91 is provided in the center of the pressing block 9 to facilitate the outflow of water. Figure 4 , Figure 5 As shown, the water flows out through the joint cavity 110 inside the water pipe joint 11.

[0036] In a preferred embodiment, the pole clamping unit includes a pressing ring 2 and a fastener 1. The fastener 1 is used to pass through the mounting hole on the outside of the pressing ring 2 and threadedly connect with the threaded hole on the base after the positive pole 200 to be tested is placed in the positive pole limiting hole of the pole limiting boss 31 which is connected to the test water flow channel, so as to lock the pressing ring 2 and press it on the upper end of the positive pole 200 to be tested.

[0037] Among them, the fastener 1 is preferably a bolt, which is convenient for fixing the positive pole pressure plate 2 and the pole limiting boss on the base 3 together. In a preferred embodiment, there are four mounting holes, which are evenly arranged on the outside of the pressure ring. Of course, it is not limited to four, and can be other numbers, as long as the pressure ring is pressed and fixed.

[0038] In a preferred embodiment, the test water system is composed of a connecting pipe 5, including an inlet pipe and a return pipe, one end of the inlet pipe and the return pipe are connected to the water pipe interface 72 for water inlet and outlet corresponding to the diverter chamber 7, and the other end is connected to the water outlet on the side of the base 3; the diverter chamber 7 has an external water source interface 71 connected to an external test water source, which is used to connect to an external water source. An optional embodiment is that the inlet pipe and the return pipe are each connected to the water pipe interface 72 of the diverter chamber 7 through a connected gate valve 6, and the gate valve 6 is arranged to control whether water is flowing through this passage.

[0039] In order to facilitate the use or replacement of different bases and the connection of the test water system, preferably, the water inlet pipe and the water return pipe are connected to the water outlet on the side of the base 3 through the quick connector 4. By using the quick connector 4, the test water system can be conveniently and quickly connected to different bases to test the positive poles and negative cover plates of batteries of different specifications. Preferably, a pressure gauge 8 is also arranged on the cavity of the diverter cavity 7 to test whether the pressure of the entire passage is within the standard value.

[0040] When the utility model is used, the base 3 is selected according to the process size, the water pipe joint 11 on the top cover 10 is connected to the hose, the external water source interface 71 of the diversion chamber 7 is connected to the test water source, and the pressure gauge 8 is adjusted to zero. The negative electrode cover plate 100 to be tested is placed in the cover plate limiting boss 32 of the base 3, the pressing block 9 is placed on the negative electrode cover plate to be tested, and the top cover 10 is placed on the pressing block 9 and tightened; the positive pole 200 to be tested is placed in the pole limiting boss 31 of the base 3, the pressing ring 2 is placed on the positive pole to be tested, and the pressing ring 2 is fixed to the base 3 with the fastener 1. After adjusting the water source pressure, let the water source enter from the external water source interface 71 of the diversion chamber 7, and confirm that the pressure of the pressure gauge 8 is correct; open the gate valve 6, the water source enters the connecting pipe 5, then enters the quick connector 4, and finally enters the base 3; the test water flows in the test water flow channel 33 in the base, and pushes up against the negative electrode cover plate 100 and the positive electrode column 200 to be tested, and applies water pressure to the bottom surface of the negative electrode cover plate 100 and the positive electrode column 200. Observe whether there is water overflow to confirm whether the product is qualified. Under the predetermined pressure of the test water, if there is no water overflow at the position of the positive electrode column and the negative electrode cover plate, the product is qualified, and if there is water overflow, the product is unqualified. Specifically, when testing the ultimate pressure, a pressure is first set according to the process, and water enters from the diverter chamber 7. When all valves are opened, the water flows through the gate valve 6, the connecting pipe 5, and the quick connector 4 in sequence and is blocked by the positive electrode column 200 and the negative electrode cover plate 100; the pressure is gradually increased to the withstand voltage limit of the positive electrode column 200 or the negative electrode cover plate 100. At this time, the positive electrode column 100 or the negative electrode cover plate 200 will rupture. If the positive electrode column 100 ruptures, the water will spray out directly. If the negative electrode cover plate 200 ruptures, the water will spray out from the hole on the top cover 10 and be recovered through the hose connected to the water pipe connector 11.

[0041] From the above, it can be seen that the cylindrical battery assembly pressure testing device of the utility model can simultaneously perform pressure tests on the negative electrode cover and the positive electrode column of the cylindrical lithium-ion battery, and can test various specifications; by testing the explosion-proof pressure of the negative electrode cover of the lithium-ion battery through water pressure, the critical value of the explosion-proof valve bursting pressure can be measured more stably and accurately; compared with the air pressure test, the water pressure test avoids the complicated high-pressure gas source device, and the equipment is simple, easy to operate, low cost, and relatively safe and reliable.

[0042] The cylindrical battery assembly pressure testing device of the utility model adopts a multi-station independent water pressure test, which can improve the test efficiency without affecting the accuracy of the test results.

[0043] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments, and the utility model can be implemented in other specific forms without departing from the spirit or basic features of the utility model.

[0044] Therefore, no matter from which point of view, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0045] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains 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.

Claims

1. Cylindrical battery assembly pressure testing device, characterized in that: It includes a base, at least one cylindrical battery assembly limiting boss arranged on the upper surface of the base, and a clamping unit matched with the cylindrical battery assembly limiting boss; a test water flow channel connected to the bottom of the cylindrical battery assembly limiting boss is arranged inside the base, and the outer side of the base is connected to a test water channel system connected to the test water flow channel.

2. The cylindrical battery assembly pressure testing device according to claim 1, characterized in that: The cylindrical battery assembly includes a negative electrode cover plate and / or a positive electrode column.

3. The cylindrical battery assembly pressure testing device according to claim 2, characterized in that: The cylindrical battery assembly includes a negative electrode cover plate and a positive electrode column; The cylindrical battery assembly pressure testing device includes a base and at least one cover plate limiting boss and at least one pole limiting boss arranged on the upper surface of the base, and a cover plate clamping unit matched with the cover plate limiting boss and a pole clamping unit matched with the pole limiting boss; a test water flow channel connected to the bottom of the cover plate limiting boss and the pole limiting boss is arranged inside the base, and the outer side of the base is connected to a test water channel system connected to the test water flow channel.

4. The cylindrical battery assembly pressure testing device according to claim 3, characterized in that: The cover plate pressing unit includes a pressing block and a top cover; the pressing block is used to press on the cover plate to be tested after the cover plate to be tested is placed in the cover plate limiting hole of the cover plate limiting boss that is connected to the test water flow channel, and the top cover is used to press the pressing block on the cover plate to be tested after being connected to the cover plate limiting boss.

5. The cylindrical battery assembly pressure testing device according to claim 4, characterized in that: The top cover has an internal thread, and the cover plate limiting boss has an external thread matching the internal thread; the top cover is threadedly connected to the cover plate limiting boss.

6. The cylindrical battery assembly pressure testing device according to claim 4, characterized in that: The top of the top cover is provided with a water pipe joint, and the center of the pressing block is provided with a water hole.

7. The cylindrical battery assembly pressure testing device according to claim 3, characterized in that: The pole clamping unit includes a pressing ring and a fastener. The fastener is used to pass through the mounting hole on the outside of the pressing ring and be threadedly connected with the threaded hole on the base after the positive pole to be tested is placed in the positive pole limiting hole of the pole limiting boss that is connected to the test water flow channel, so as to lock the pressing ring and press it on the upper end of the positive pole to be tested.

8. The cylindrical battery assembly pressure testing device according to claim 1, characterized in that: The test water system includes an inlet pipe and a return pipe, one end of which is connected to the water pipe interface of the diversion chamber, and the other end is connected to the water outlet on the side of the base; the diversion chamber has an external water source interface connected to an external test water source.

9. The cylindrical battery assembly pressure testing device according to claim 8, characterized in that: The water inlet pipeline and the water return pipeline are respectively connected to the water pipe interface for water inlet and outlet of the diversion chamber through the connected gate valve; the water inlet pipeline and the water return pipeline are connected to the water outlet on the side of the base through a quick connector.

10. The cylindrical battery assembly pressure testing device according to claim 8, characterized in that: A pressure gauge is arranged on the cavity body of the diversion cavity.

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