Cover plate assembly, single battery and battery pack

Abstract

The utility model discloses a cover plate assembly, a single battery and a battery pack, and belongs to the technical field of batteries, the cover plate assembly comprises a cover plate body, an anti-explosion valve and a connecting frame, and the cover plate body is provided with an anti-explosion hole; the anti-explosion valve is connected with the cover plate body and covers the anti-explosion hole; the connecting frame is connected to one side of the cover plate body and is configured to be supported between the cover plate body and the electrode assembly, the connecting frame comprises a main body part and a plurality of supporting legs, the main body part and the anti-explosion valve are correspondingly arranged, the main body part and the cover plate body are arranged at an interval, and a gap capable of being communicated with the anti-explosion hole is formed; the supporting legs are located between the main body part and the cover plate body and are connected with the main body part and the cover plate body. The connecting frame is arranged to support and fix the electrode assembly and improve the stability of the electrode assembly, and meanwhile, the gap capable of being communicated with the explosion-proof hole is formed between the main body part and the cover plate body, so that the exhaust requirement of the single battery is ensured, and the safety of the single battery is improved.

Description

Technical Field

[0001] This application belongs to the field of battery technology, specifically relating to a cover plate assembly, a single cell, and a battery pack. Background Technology

[0002] The battery pack requires a plastic cover to be installed on the cover assembly to insulate and fix the electrode assembly. However, when the internal temperature of the battery pack is around 150°C, the plastic cover is prone to melting and failure, leaving the electrode assembly in a non-fixed state. This can obstruct the venting of the explosion-proof valve, posing a significant safety hazard. Utility Model Content

[0003] The purpose of this utility model is to provide a cover plate assembly that overcomes the technical problems of the current plastic easily melting and failing, the electrode assembly being in a non-fixed state, and the explosion-proof valve being easily blocked, posing significant safety hazards. Another purpose of this application is to provide a single battery cell. Yet another purpose of this application is to provide a battery pack.

[0004] Technical solution: An embodiment of this application discloses a cover plate assembly, comprising:

[0005] The cover plate body has explosion-proof holes;

[0006] An explosion-proof valve is connected to the cover plate body and seals the explosion-proof hole;

[0007] A connecting frame is connected to one side of the cover plate body and configured to support the cover plate body and the electrode assembly. The connecting frame includes a main body and a plurality of legs. The main body is correspondingly disposed to the explosion-proof valve. The main body and the cover plate body are spaced apart and form a gap that can communicate with the explosion-proof hole. The plurality of legs are located between the main body and the cover plate body and connect the main body and the cover plate body.

[0008] In some embodiments, the cover plate body includes a boss protruding toward one side of the connecting frame, the boss being connected to the support leg.

[0009] In some embodiments, a plurality of bosses are provided, and the plurality of bosses are arranged around the explosion-proof valve and are correspondingly arranged with the support legs.

[0010] In some embodiments, the boss has a mounting groove on the side of the boss facing the connecting frame, and the leg is at least partially embedded in the mounting groove.

[0011] In some embodiments, the boss includes a protrusion and a limiting portion connected together, the limiting portion being located on the side of the protrusion facing the connecting frame, and the limiting portion and the protrusion forming the mounting groove.

[0012] In some embodiments, the main body has an exhaust port, which is provided corresponding to the explosion-proof hole.

[0013] In some embodiments, the connecting frame includes a shielding portion disposed within the vent hole and connected to the main body portion, for shielding part of the vent hole.

[0014] In some embodiments, the area of ​​the vent hole is S1 mm. 2 Along the thickness direction of the cover plate body, the orthogonal projection area of ​​the blocking part on the cover plate body is S2 mm. 2 The condition 2.5 ≤ S1 / S2 ≤ 4 is satisfied.

[0015] This application also discloses a single battery cell, including the cover plate assembly as described in the above embodiments.

[0016] This application also discloses a battery pack, including a cover assembly as described in the above embodiments, or including a single battery cell as described in the above embodiments.

[0017] Beneficial Effects: An embodiment of this application provides a cover plate assembly, comprising: a cover plate body, an explosion-proof valve, and a connecting frame. The cover plate body has an explosion-proof hole; the explosion-proof valve is connected to the cover plate body and seals the explosion-proof hole; the connecting frame is connected to one side of the cover plate body and configured to support between the cover plate body and the electrode assembly. The connecting frame includes a main body and multiple legs. The main body is correspondingly disposed with the explosion-proof valve, and the main body and the cover plate body are spaced apart to form a gap that can communicate with the explosion-proof hole. The multiple legs are located between the main body and the cover plate body and connect the main body and the cover plate body. By providing the connecting frame, the electrode assembly is supported and fixed, improving the stability of the electrode assembly; simultaneously, the gap between the main body and the cover plate body that can communicate with the explosion-proof hole ensures the venting requirements of the individual battery and improves the safety of the individual battery.

[0018] The single-cell battery of this application embodiment includes the cover plate assembly as described in the above embodiments. Therefore, it can have all the technical features and effects of the above-described cover plate assembly, which will not be repeated here.

[0019] The battery pack of this application embodiment includes the cover plate assembly or the single cell as described in the above embodiments. Therefore, it can have all the technical features and effects of the above-described cover plate assembly or single cell, which will not be repeated here. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a three-dimensional structural diagram of the cover plate assembly according to an embodiment of this application;

[0022] Figure 2 This is a three-dimensional structural diagram of the cover body in the cover assembly of this application embodiment, showing the boss;

[0023] Figure 3 This is a three-dimensional structural diagram of the connecting frame in the cover plate assembly according to an embodiment of this application;

[0024] Figure 4 This is a front view schematic diagram of the cover plate body in the cover plate assembly of this application embodiment;

[0025] Figure 5 This is a three-dimensional structural schematic diagram of a cover plate assembly according to another embodiment of this application;

[0026] Figure 6 This is a three-dimensional structural diagram of the cover body in a cover assembly according to another embodiment of the present application. The diagram shows the mounting groove formed by the protrusion and the limiting part.

[0027] Figure 7 This is a schematic diagram of the exploded structure of a single battery cell according to an embodiment of this application, showing the cover plate assembly.

[0028] Reference numerals: 10, cover plate body; 100, explosion-proof hole; 20, connecting frame; 201, main body; 202, support leg; 200, gap; 101, boss; 1010, mounting groove; 1011, protrusion; 1012, limiting part; 2010, vent hole; 2011, shielding part. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0030] In the description of this application, it should be understood that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. In the description of this application, "multiple" means two or more, and "at least one" can refer to one, two, or more, unless otherwise explicitly specified. The terms "first," "second," and "third," etc., are only for the convenience of description and are used to name parts or embodiments by number, and do not imply any order of importance between the parts or embodiments.

[0031] As a preamble to the embodiments of this application, a single battery cell typically includes: a cover assembly (integrating terminals, an explosion-proof valve, an electrolyte injection port, etc.), a casing, an electrode assembly, and an electrolyte. The cover assembly and casing, after welding, form a sealed space with sufficient mechanical strength to protect the electrode assembly. A lower plastic layer (insulating material) on the cover assembly securely supports the electrode assembly. The explosion-proof valve structure is primarily used for the directional discharge of high-temperature, high-pressure gases inside the battery in the event of thermal runaway due to an internal short circuit, thus improving battery safety. The lower plastic layer is used for insulation and fixation of the electrode assembly; however, it is generally made of polypropylene, which has very limited strength and high-temperature resistance. Typically, at around 150 degrees Celsius, these internal fixing structures of the single battery cell will melt and fail.

[0032] However, the temperature at which a single cell experiences thermal runaway is usually much higher than the melting point of these insulating materials. At this point, only the electrode assembly remains inside the single cell. Due to the melting of the insulating protective material, the gap between the electrode assembly and the cover assembly increases. The electrode assembly has a high degree of freedom inside the single cell. As the high-temperature and high-pressure gas is vented directionally towards the explosion-proof valve, the electrode assembly will randomly move with the high-temperature and high-pressure gas flow and block the explosion-proof valve on the cover assembly, thereby blocking the exhaust channel and greatly reducing the exhaust effect of the explosion-proof valve, thus reducing the safety performance of the single cell.

[0033] In view of the above, embodiments of this application provide a cover plate assembly, which aims to solve at least one of the above-mentioned technical problems.

[0034] Please see Figure 1As shown in the embodiment of this application, a cover plate assembly includes: a cover plate body 10, an explosion-proof valve, and a connecting frame 20; wherein, the cover plate body 10 has an explosion-proof hole 100; the explosion-proof valve is connected to the cover plate body 10 and covers the explosion-proof hole 100; the connecting frame 20 is connected to one side of the cover plate body 10 and is configured to be supported between the cover plate body 10 and the electrode assembly, the connecting frame 20 includes a main body 201 and a plurality of legs 202, the main body 201 is correspondingly disposed with the explosion-proof valve, the main body 201 and the cover plate body 10 are spaced apart and form a gap 200 that can communicate with the explosion-proof hole 100, and the plurality of legs 202 are located between the main body 201 and the cover plate body 10 and connect the main body 201 and the cover plate body 10.

[0035] It should be understood that the cover plate body 10 can be made of plain aluminum sheet, and the connecting frame 20 can also be made of plain aluminum sheet by stamping. The connecting frame 20 and the cover plate body 10 can be fixedly connected by welding. Alternatively, the connecting frame 20 can also be made of other high-melting-point, high-temperature resistant insulating materials, and the connection method between the connecting frame 20 and the cover plate body 10 can also be other fixed connection methods, including but not limited to threaded connection, snap-fit, and riveting. The connecting frame 20 of this application includes a main body 201 and multiple legs 202. The connecting frame 20 can be integrally molded or assembled. By correspondingly setting the main body 201 with the explosion-proof valve, the exhaust area of ​​the explosion-proof valve can be protected, preventing high-temperature and high-pressure gas inside the individual battery from being discharged directly into the explosion-proof valve. The gap 200 formed between the main body 201 and the cover plate body 10 can effectively reduce the impact force of high-temperature and high-pressure gas, reduce damage to the explosion-proof valve, and improve the service life of the explosion-proof valve. The use of multiple support legs 202 can effectively support and connect the main body 201 and the cover plate body 10, which not only provides support and fixation for the electrode assembly, but also reduces the internal space occupied by the individual battery, reduces the weight of the cover plate assembly, and ensures that the gap 200 formed between the main body 201 and the cover plate body 10 has a good exhaust effect.

[0036] In some embodiments, please refer to Figure 2 As shown, the cover plate body 10 includes a boss 101 protruding from one side facing the connecting frame 20, and the boss 101 is connected to the support leg 202. It should be understood that the boss 101 can be formed by stamping the cover plate body 10, and the boss 101 can be a conical structure. By providing the boss 101 on the cover plate body 10, on the one hand, the boss 101 can avoid the problem of insufficient support strength caused by the excessive length of the support leg 202, so as to ensure the reliability and stability of the connecting frame 20 supported on the cover plate body 10 and the electrode assembly; on the other hand, the boss 101 can increase the size of the gap 200 formed between the main body 201 and the cover plate body 10, so as to further increase the flow rate of high temperature and high pressure gas flowing through the gap 200, so as to ensure the exhaust requirements of the electrode assembly.

[0037] In some embodiments, please refer to Figure 2 As shown, multiple bosses 101 are provided, arranged around the explosion-proof valve and corresponding to the support legs 202. By providing multiple bosses 101, the weight of the cover plate assembly can be reduced while providing support and fixation for the connecting frame 20. At the same time, the space occupied inside the individual battery can be reduced, and the flow rate of high-temperature and high-pressure gas flowing through the gap 200 can be further increased to ensure the exhaust requirements of the electrode assembly.

[0038] In some embodiments, please refer to Figure 5 and Figure 6 As shown, the boss 101 has a mounting groove 1010, which is located on the side of the boss 101 facing the connecting frame 20. The support leg 202 is at least partially embedded in the mounting groove 1010. By creating the mounting groove 1010 on the side of the boss 101 facing the connecting frame 20, and by having the support leg 202 at least partially embedded in the mounting groove 1010, the assembly efficiency of the connecting frame 20 is improved. Furthermore, since the support leg 202 is partially embedded in the mounting groove 1010 and fixedly connected to the inner wall of the mounting groove 1010, the overall fixing effect is improved, further ensuring the overall strength of the explosion-proof valve's protective structure.

[0039] In some embodiments, please refer to Figure 5 As shown, the boss 101 includes a connected protrusion 1011 and a limiting part 1012. The limiting part 1012 is located on the side of the protrusion 1011 facing the connecting frame 20. The limiting part 1012 and the protrusion 1011 form a mounting groove 1010. It should be understood that the support leg 202 is welded to the protrusion 1011 and the limiting part 1012 at different positions, which improves the connection stability of the support leg 202. At the same time, the mounting groove 1010 formed by the limiting part 1012 and the protrusion 1011 can accommodate and protect the support leg 202, preventing deformation or failure of the connection between the support leg 202 and the boss 101, and further ensuring the overall strength of the explosion-proof valve's protective structure.

[0040] In some embodiments, please refer to Figure 4 As shown, the boss 101 has a first dimension a mm along the thickness direction of the cover plate assembly, satisfying: 1 ≤ a ≤ 2. In some embodiments, the area of ​​the vent 2010 is S1 mm. 2 Along the thickness direction of the cover plate body 10, the orthogonal projection area of ​​the blocking part 2011 on the cover plate body 10 is S2mm. 2The condition 2.5 ≤ S1 / S2 ≤ 4 is satisfied. Specifically, S1 / S2 can be any value from 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, and 4, or a range between any two values. When S1 / S2 is within the above range, the venting requirements of the electrode assembly are guaranteed, while also providing a good level of protection. This reduces the probability of damage to the shielding part and ensures effective shielding while meeting the venting requirements of the electrode assembly.

[0041] Next, several embodiments are provided to illustrate the effect of the cover plate assembly of this application. S1 and S2 can be obtained by selecting common area measurement methods. For example, for the vent 2010, the measurement method for area S1 can be specifically selected according to its shape. When the vent 2010 is circular, square, rectangular, etc., measuring tools such as vernier calipers and micrometers can be used to measure the corresponding dimensions of the vent 2010, and the area S1 can be calculated using geometric formulas. For the vent 2010 having an irregular hole structure, image processing can also be used for measurement. For example, an image of the vent 2010 can be acquired, the image can be loaded using image processing software, and S1 can be measured using the software. Alternatively, a projection method can be used to measure the image area of ​​the vent 2010 using a projection measuring device (such as a digital microscope or image measuring instrument), thereby obtaining the area S1. Correspondingly, the area S2 can be obtained directly through projection measurement or through image processing using image software.

[0042] Among them, the protective effect of S1 / S2 on the cover plate assembly can be determined by safety testing to see if the explosion-proof valve exhaust effect meets the design requirements, and the cover plate assembly can be disassembled to determine if the protective structure is intact.

[0043] The test results of the examples are shown in the table below:

[0044]

[0045]

[0046] As shown in the table above, when S1 / S2 is within the range of 2.5 to 4, the explosion-proof valve's venting effect meets the design requirements, and the cell disassembly protection structure remains intact. When S1 / S2 is less than 2.5, the projected area S2 mm of the shielding part 2011 on the cover plate body 10 is... 2 The larger the area, the stronger its structural support and the less prone to deformation; however, the larger shielding area slightly affects the exhaust of the explosion-proof valve. When S1 / S2 is greater than 4, the projected area of ​​the shielding part 2011 on the cover plate body 10 is S2 mm. 2As the size decreases, the structural support strength weakens, the shielding area becomes smaller, the explosion-proof valve's venting effect meets design requirements, and the protective structure for cell disassembly exhibits slight deformation.

[0047] In some embodiments, please refer to Figure 1 and Figure 3 As shown, the main body 201 has an exhaust port 2010, which is correspondingly provided with the explosion-proof hole 100. It should be understood that the exhaust port 2010 provided on the main body 201, which is correspondingly provided with the explosion-proof hole 100, can further ensure the exhaust requirements of the electrode assembly.

[0048] In some embodiments, please refer to Figure 3 As shown, the connector includes a shielding part 2011, which is disposed within the vent 2010 and connected to the main body 201, for partially shielding the vent 2010. It should be understood that the main body 201 is correspondingly positioned to the explosion-proof valve, and the vent 2010 is also correspondingly positioned to the explosion-proof hole 100. The shielding part 2011, disposed within the vent 2010, can effectively prevent internal combustibles from being ejected outwards through the explosion-proof valve in the event of thermal runaway of the electrode assembly, thus improving the safety performance of the individual battery.

[0049] Please see Figure 7 As shown in the illustration, this application also discloses a single-cell battery, including a cover assembly as described in the above embodiments. Therefore, it can possess all the technical features and effects of the above-described cover assembly, which will not be repeated here.

[0050] This application also discloses a battery pack, including a cover assembly as described in the above embodiments, or including a single battery cell as described in the above embodiments. Therefore, it can possess all the technical features and effects of the above-described cover assembly or single battery cell, which will not be repeated here.

[0051] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0052] The foregoing has provided a detailed description of a cover plate assembly, a single battery cell, and a battery pack provided in the embodiments of this application, and has used specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A cover plate assembly, characterized in that, include: The cover plate body has explosion-proof holes; An explosion-proof valve is connected to the cover plate body and seals the explosion-proof hole; A connecting frame is connected to one side of the cover plate body and configured to support the cover plate body and the electrode assembly. The connecting frame includes a main body and a plurality of legs. The main body is correspondingly disposed to the explosion-proof valve. The main body and the cover plate body are spaced apart and form a gap that can communicate with the explosion-proof hole. The plurality of legs are located between the main body and the cover plate body and connect the main body and the cover plate body.

2. The cover plate assembly according to claim 1, characterized in that, The cover plate body includes a boss protruding from one side of the connecting frame, and the boss is connected to the support leg.

3. The cover plate assembly according to claim 2, characterized in that, The valve has multiple protrusions arranged around it and corresponding to the support legs.

4. The cover plate assembly according to claim 2 or 3, characterized in that, The boss has a mounting groove, which is located on the side of the boss facing the connecting frame, and the support leg is at least partially embedded in the mounting groove.

5. The cover plate assembly according to claim 4, characterized in that, The boss includes a protrusion and a limiting part connected together. The limiting part is located on the side of the protrusion facing the connecting frame, and the limiting part and the protrusion form the mounting groove.

6. The cover plate assembly according to claim 1, characterized in that, The main body has an exhaust port, which is provided in correspondence with the explosion-proof port.

7. The cover plate assembly according to claim 6, characterized in that, The connecting frame includes a shielding part, which is disposed inside the exhaust hole and connected to the main body, for shielding part of the exhaust hole.

8. The cover plate assembly according to claim 7, characterized in that, The area of ​​the exhaust port is S1mm. 2 Along the thickness direction of the cover plate body, the orthogonal projection area of ​​the blocking part on the cover plate body is S2mm. 2 The condition 2.5 ≤ S1 / S2 ≤ 4.0 is met. 。 9. A single-cell battery, characterized in that, Includes the cover plate assembly as described in any one of claims 1 to 8 above.

10. A battery pack, characterized in that, It includes the cover assembly as described in any one of claims 1 to 8, or it includes the single cell as described in claim 9.

Images