End cap assembly and battery cell

Abstract

The present application provides an end cover assembly, which includes an end cover and a sealing assembly. The sealing assembly is used to seal the liquid injection hole on the end cover. The sealing assembly includes a first fixing member, a second fixing member, a plugging assembly and a driving assembly. The end cover assembly has a first state and a second state. When the end cover assembly is in the first state, a part of the plugging assembly abuts against the hole wall of the second fixing member to seal the liquid injection port on the second fixing member. When the end cover assembly is in the second state, a part of the driving assembly passes through the third through hole of the second fixing member, and one end of the driving assembly is located in the second through hole of the second fixing member and abuts against the plugging assembly, and there is a gap between the plugging assembly and the hole wall. The present application also provides a battery cell, which includes a housing and an end cover assembly. The end cover assembly and the battery cell provided by the present application can extend the service life of the battery cell, and the operation is simple during secondary liquid injection, and the sealing effect is good after liquid injection.

Description

Technical Field

[0001] The present application relates to the field of batteries, and particularly to an end cover assembly and a battery cell. Background Art

[0002] A battery cell generally includes a housing, an electrode assembly and an end cover. The electrode assembly is disposed inside the inner cavity of the housing, and the end cover is disposed at the opening of the housing to seal the inner cavity of the housing. Among them, a liquid injection hole is usually provided on the end cover, so that electrolyte can be injected into the inner cavity of the housing through the liquid injection hole, so that the electrode assembly is immersed in the electrolyte. In order to ensure that after the liquid injection is completed, the electrode assembly can be placed in a sealed cavity, a sealing structure is usually used to seal the liquid injection hole.

[0003] During the use of the battery, after experiencing multiple charge and discharge cycles, the electrolyte in the battery is consumed. To extend the service life of the battery, it is necessary to replenish the battery with liquid. However, in the existing process, a welding process is used to seal the liquid injection hole. After the sealing is completed, the liquid injection hole is difficult to open again, and secondary liquid injection cannot be performed; or it is necessary to forcefully disassemble the sealing structure and cause damage to the end cover to complete the liquid injection, which is not conducive to secondary liquid injection. Summary of the Invention

[0004] In view of the above problems, embodiments of the present application provide an end cover assembly and a battery cell, which can extend the service life of the battery cell, and are easy to operate during secondary liquid injection, and have good sealing effect after liquid injection.

[0005] In a first aspect of the present application, an end cover assembly is provided. The end cover assembly includes an end cover and a sealing assembly. The end cover has a liquid injection hole, and the sealing assembly is used to seal the liquid injection hole. The end cover assembly has a first state and a second state. The sealing assembly includes:

[0006] A first fixing member, the first fixing member is installed in the liquid injection hole, and the first fixing member has a first through hole communicating with the liquid injection hole;

[0007] A second fixing member, the second fixing member is stacked with the first fixing member, the second fixing member has a second through hole penetrating through the second fixing member, the second through hole forms a liquid injection port at one end of the second fixing member facing away from the first fixing member, the second through hole communicates with the first through hole, the second fixing member has a hole wall forming the second through hole and a third through hole penetrating through the hole wall, and the third through hole communicates with the second through hole;

[0008] A plugging assembly, the plugging assembly is used to seal the liquid injection port;

[0009] A driving assembly, at least a part of the driving assembly can penetrate through the third through hole;

[0010] When the end cover assembly is in the first state, a part of the plugging assembly abuts against the hole wall to seal the liquid injection port; when the end cover assembly is in the second state, a part of the driving assembly penetrates through the third through hole, and one end of the driving assembly is located in the second through hole and abuts against the plugging assembly, and there is a gap between the plugging assembly and the hole wall.

[0011] It should be noted that the end cover assembly described in the embodiments of the present application can be applied to a battery cell to cover the housing of the battery cell and achieve sealing of the battery cell, and each embodiment of the present application is described by taking the application of the end cover assembly to the battery cell as an example.

[0012] In the embodiments of the present application, by using the sealing assembly described in the present application to seal the liquid injection hole, the battery cell can be refilled, thereby extending the service life of the battery cell and improving the resource utilization rate. Moreover, the sealing and liquid injection operations of the battery cell are convenient, the secondary liquid injection efficiency is high, and the liquid injection port can be opened without forcibly disassembling the sealing assembly during liquid injection, which can avoid damage to the end cover and the sealing assembly caused by forcibly disassembling the sealing assembly and ensure the sealing reliability.

[0013] Furthermore, the sealing assembly further includes a first elastic member, the first elastic member connects the plugging assembly and the first fixing member, the first elastic member is telescopable in the direction from the plugging assembly to the first fixing member, when the end cover assembly is in the first state, the dimension of the first elastic member in the direction from the plugging assembly to the first fixing member is d1; when the end cover assembly is in the second state, the dimension of the first elastic member in the direction from the plugging assembly to the first fixing member is d2, where d2 > d1.

[0014] In the embodiments of the present application, by providing the first elastic member, the plugging assembly can be automatically sealed, the liquid injection operation is convenient, and the liquid injection efficiency is high.

[0015] Furthermore, the driving assembly includes a driving rod and a driving block. When the end cover assembly is in the second state, a part of the driving rod penetrates through the third through hole, the driving block is located in the second through hole, and one end of the driving block is connected to the driving rod and the other end abuts against the plugging assembly.

[0016] In the embodiments of the present application, by providing the driving block to abut against the plugging assembly, the contact area between the driving assembly and the plugging assembly can be increased, which is convenient for the driving assembly to push the plugging assembly to move, so as to further improve the liquid injection efficiency.

[0017] Further, the driving assembly further includes a second elastic member sleeved on the outer peripheral side of the driving rod, and one end of the second elastic member is fixedly connected to the driving block. The second elastic member can contract along the extending direction of the driving rod. When the end cover assembly is in the first state, the dimension of the elastic member along the extending direction of the driving rod is d3; when the end cover assembly is in the second state, the dimension of the second elastic member along the extending direction of the driving rod is d4, where d4 > d3.

[0018] In the embodiments of the present application, by providing the cooperation of the second elastic member and the first elastic member, the position of the plugging assembly in the second through hole can be further controlled, improving the reliability of the sealing assembly.

[0019] In some embodiments of the present application, the second through hole includes a first hole section and a second hole section arranged in sequence. The first hole section is adjacent to the liquid injection port, and a step surface facing the liquid injection port is formed between the first hole section and the second hole section. When the end cover assembly is in the first state, at least part of the plugging assembly abuts against the step surface; when the end cover assembly is in the second state, there is a gap between the plugging assembly and the step surface.

[0020] In the embodiments of the present application, by providing the step surface, not only can the situation of the plugging assembly further extending into the second through hole and causing sealing failure be avoided, but also the flow path of the electrolyte can be increased by providing the step surface, improving the contact area between the plugging assembly and the hole wall, and further improving the sealing effect.

[0021] Further, the sealing assembly further includes a sealing ring disposed in the third through hole, and at least part of the driving rod passes through the sealing ring.

[0022] In the embodiments of the present application, by providing the sealing ring, the sealing of the third through hole can be further achieved, avoiding the electrolyte flowing out from the third through hole and affecting the sealing performance of the sealing assembly.

[0023] Further, one end of the driving block close to the driving rod has a groove, and one end of the driving rod is located in the groove.

[0024] In the embodiments of the present application, by providing the groove, the driving rod can form a more stable connection with the driving block, thereby further improving the reliability of the sealing assembly.

[0025] Further, the plugging assembly includes a first plugging member and a connecting member. The connecting member is connected to the first elastic member, and there is a gap between the outer peripheral side surface of the connecting member and the hole wall. The first plugging member is disposed on a side of the connecting member away from the first elastic member. When the end cap assembly is in the first state, the first plugging member abuts against the hole wall to seal the liquid injection port; when the end cap assembly is in the second state, there is a gap between the first plugging member and the hole wall.

[0026] In an embodiment of the present application, by providing a gap between the outer peripheral side surface of the connecting member and the hole wall, the plugging assembly can open the liquid injection port without being completely exposed from the second through hole, further improving the liquid injection efficiency of the battery cell.

[0027] Further, the plugging assembly further includes a second plugging member. The second plugging member is disposed between the first plugging member and the connecting member. The second plugging member is deformable. When the end cap assembly is in the first state, the second plugging member is in interference fit with the hole wall to seal the liquid injection port; when the end cap assembly is in the second state, there is a gap between the second plugging member and the hole wall.

[0028] In an embodiment of the present application, by providing the second plugging member in interference fit with the hole wall, it can further prevent the electrolyte from flowing out from the connection between the plugging assembly and the hole wall, improving the sealing performance of the sealing assembly.

[0029] Further, the connecting member includes a first section and a second section. The second section is connected to the first elastic member. The first section is located on a side of the second section away from the first elastic member, and the diameter of the second section gradually decreases in a direction away from the first section. When the end cap assembly is in the second state, the second section abuts against the driving assembly.

[0030] In an embodiment of the present application, by providing the diameter of the second section gradually decreasing in a direction away from the first section, when the driving assembly acts on the connecting member, a force can be generated in a direction from the connecting member to the first plugging member, thereby improving the reliability of the sealing assembly.

[0031] Further, the connecting member has a through hole penetrating the connecting member. The first fixing member includes a first body portion and an extending portion extending towards the connecting member. The extending portion is located in the through hole, and the first elastic member is sleeved on the outer peripheral side of the extending portion.

[0032] In the embodiments of the present application, by providing the through hole, the connection reliability between the connecting member and the first fixing member can be improved. Moreover, since the first elastic member is sleeved on the outer peripheral side of the extending portion, the first elastic member is not easily deformed, so that the connecting member can move in a preset direction, further improving the reliability of the sealing assembly.

[0033] Further, the first fixing member further includes a second body portion connected to the extending portion, and a connecting portion connecting the second body portion and the first body portion. The first body portion, the second body portion and the connecting portion jointly define the first through hole.

[0034] In the embodiments of the present application, by providing the second body portion and the connecting portion to form the first through hole, while ensuring the smooth inflow of the electrolyte into the battery cell, the structural stability of the first fixing member can be improved.

[0035] Further, the first fixing member includes a plurality of connecting portions, and the plurality of connecting portions are spaced between the second body portion and the first body portion. The first body portion, the second body portion and the plurality of connecting portions jointly define a plurality of the first through holes.

[0036] In the embodiments of the present application, by providing the plurality of connecting portions, the structural stability of the first fixing member can be further improved, preventing the plurality of connecting portions from breaking under the elastic force of the first elastic member, resulting in the separation of the second body portion and the extending portion from the first body portion and causing the failure of the sealing assembly.

[0037] An embodiment of the second aspect of the present application provides a battery cell, which includes:

[0038] A housing having an opening;

[0039] An end cover assembly covering the opening. For the introduction of the end cover assembly, please refer to the descriptions in the previous embodiments and will not be elaborated here.

[0040] In the embodiments of the present application, when the electrolyte in the battery cell is consumed to the point where it cannot be used normally, by using the end cover assembly of the present application, the electrolyte can be added to the inside of the battery cell in a timely manner, and the injection hole can be resealed after the secondary liquid injection is completed, realizing repeated liquid injection to extend the service life of the battery cell, and the liquid injection operation is simple and the liquid injection efficiency is high. Description of the Drawings

[0041] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0042] Figure 1 Stereoscopic schematic diagram of an end cap assembly provided by an embodiment of the present application;

[0043] Figure 2 For Figure 1 Stereoscopic exploded view of the provided end cap assembly;

[0044] Figure 3 For Figure 1 Top view of the provided end cap assembly;

[0045] Figure 4 For Figure 3 Schematic cross-sectional view along line A-A when the end cap assembly is in the first state in

[0046] Figure 5 For Figure 3 Schematic cross-sectional view along line A-A when the end cap assembly is in the second state in

[0047] Figure 6 For Figure 2 Stereoscopic schematic diagram of the driving block in

[0048] Figure 7 Stereoscopic schematic diagram of a battery cell provided by an embodiment of the present application;

[0049] Figure 8 For Figure 7 Stereoscopic exploded view of the provided battery cell.

[0050] Explanation of reference numerals:

[0051] 100 - End - cover assembly, 110 - End - cover, 111 - Liquid - injection hole, 120 - Sealing assembly, 121 - First fixing part, 1211 - First through - hole, 1212 - First body part, 1213 - Extension part, 1214 - Second body part, 1215 - Connection part, 122 - Second fixing part, 1221 - Second through - hole, 1221a - First hole section, 1221b - Second hole section, 1221c - Step surface, 1222 - Liquid - injection port, 1223 - Hole wall, 1224 - Third through - hole, 123 - Plugging assembly, 1231 - First plugging part, 1232 - Connecting part, 1232a - First section, 1232b - Second section, 1232c - Through - hole, 1233 - Second plugging part, 124 - Driving assembly, 1241 - Driving rod, 1242 - Driving block, 1242a - Groove, 1243 - Second elastic part, 125 - First elastic part, 126 - Sealing ring;

[0052] 200 - Battery cell, 210 - Housing, 211 - Opening. Detailed implementation manners

[0053] In order to enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.

[0054] The terms "first", "second", etc. in the specification, claims and above - mentioned drawings of this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non - exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices. The technical solutions in the embodiments of this application will be described below with reference to the drawings.

[0055] It should be noted that, for the convenience of description, in the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, the detailed description of the same components is omitted in different embodiments.

[0056] Please refer to Figures 1 to 5 , Figure 1 which is a three - dimensional schematic diagram of the end - cover assembly provided by an embodiment of this application; Figure 2 is Figure 1Exploded perspective view of the provided end cap assembly; Figure 3 is Figure 1 Top view of the provided end cap assembly; Figure 4 is Figure 3 Schematic cross-sectional view along line A-A when the end cap assembly is in the first state in the middle; Figure 5 is Figure 3 Schematic cross-sectional view along line A-A when the end cap assembly is in the second state in the middle. An embodiment of the first aspect of the present application provides an end cap assembly 100, and the end cap assembly 100 includes an end cap 110 and a sealing assembly 120. The end cap 110 has a liquid injection hole 111, the sealing assembly 120 is used to seal the liquid injection hole 111, and the end cap assembly 100 has a first state and a second state. The sealing assembly 120 includes a first fixing member 121, a second fixing member 122, a plugging assembly 123, and a driving assembly 124. Among them, the first fixing member 121 is installed in the liquid injection hole 111, and the first fixing member 121 has a first through hole 1211 communicating with the liquid injection hole 111. The second fixing member 122 is stacked with the first fixing member 121, and the second fixing member 122 has a second through hole 1221 penetrating through the second fixing member 122. The second through hole 1221 forms a liquid injection port 1222 at one end of the second fixing member 122 facing away from the first fixing member 121, and the second through hole 1221 communicates with the first through hole 1211. The second fixing member 122 has a hole wall 1223 forming the second through hole 1221 and a third through hole 1224 penetrating through the hole wall 1223. The third through hole 1224 communicates with the second through hole 1221. The plugging assembly 123 is used to seal the liquid injection port 1222. At least a part of the driving assembly 124 can be inserted into the third through hole 1224. When the end cap assembly 100 is in the first state, a part of the plugging assembly 123 abuts against the hole wall 1223 to seal the liquid injection port 1222; when the end cap assembly 100 is in the second state, a part of the driving assembly 124 is inserted into the third through hole 1224, and one end of the driving assembly 124 is located in the second through hole 1221 and abuts against the plugging assembly 123, and there is a gap between the plugging assembly 123 and the hole wall 1223.

[0057] It should be noted that the end cap assembly 100 described in the embodiments of the present application can be applied to a battery cell 200 (please refer to Figure 7) to cover the housing 210 of the battery cell 200 and achieve the sealing of the battery cell 200. In each embodiment of the present application, the end cap assembly 100 applied to the battery cell 200 is taken as an example for illustration. Among them, the actual shape of the end cap 110 can be adjusted according to the actual shape of the battery cell 200, and the present application does not make specific limitations in this regard. Of course, in other embodiments, the end cap assembly 100 described in the present application can also be applied to other scenarios that need to be sealed. Here, the usage scenarios of the end cap assembly 100 described in the present application are not limited.

[0058] The first state and the second state of the end cap assembly 100 will be described in detail below. When the end cap assembly 100 is in the first state, a part of the plugging assembly 123 abuts against the hole wall 1223 to seal the liquid injection port 1222. Therefore, when the end cap assembly 100 is applied to the battery cell 200, the electrolyte in the battery cell 200 is sealed by the plugging assembly 123. When the end cap assembly 100 is in the second state, there is a gap between the plugging assembly 123 and the hole wall 1223. Therefore, when the end cap assembly 100 is applied to the battery cell 200, the electrolyte can be injected into the battery cell 200 through the gap between the plugging assembly 123 and the hole wall 1223.

[0059] Specifically, the first fixing member 121 can be installed in the liquid injection hole 111 or on the surface of the end cap assembly 100 above the liquid injection hole 111. No limitation is made here, as long as the first fixing member 121 can be fixed at the liquid injection hole 111 and the first through hole 1211 is communicated with the second through hole 1221. The driving assembly 124 is used to push the plugging assembly 123 so that the plugging assembly 123 can move relative to the liquid injection port 1222 to seal or open the liquid injection port 1222. Please refer to Figure 5 , when the battery cell 200 needs to be filled with liquid, an external force is applied to the driving assembly 124 so that the driving assembly 124 abuts against the plugging assembly 123 and pushes a part of the plugging assembly 123 to move in a direction away from the liquid injection port 1222 until the liquid injection port 1222 is opened, and the electrolyte is injected into the liquid injection port 1222. The electrolyte enters from the liquid injection port 1222 and sequentially flows through the second through hole 1221, the first through hole 1211, and the liquid injection hole 111 to reach the inside of the housing 210; Please refer to Figure 4When the injection is completed, the external force applied to the driving component 124 is removed, and an external force is applied to the sealing component 123 from the outside of the battery cell 200, or a pulling force is provided to the sealing component 123 from the inside of the sealing component 120, so that the sealing component 123 can reseal the injection port 1222.

[0060] It can be understood that the end cap assembly 100 described in the present application can switch between the first state and the second state by setting the sealing assembly 120, that is, the battery cell 200 can switch between the sealed state and the injectable state, so that the battery cell 200 can be repeatedly injected. By setting a third through hole 1224 for the drive assembly 124 to pass through on the hole wall 1223, when injection is not required, the drive assembly 124 can also be removed from the third through hole 1224 to reduce the weight of the battery cell 200 and improve the energy density of the battery cell 200. In addition, by setting the drive assembly 124 in the third through hole 1224, the drive assembly 124 and the injection port 1222 are staggered to avoid the drive assembly 124 interfering with the injection of the battery cell 200 from the injection port 1222.

[0061] Therefore, by using the sealing assembly 120 described in the present application to seal the injection hole 111, the battery cell 200 can be repeatedly injected, thereby extending the service life of the battery cell 200 and improving resource utilization. In addition, the sealing and injection operation of the battery cell 200 is convenient, and the secondary injection efficiency is high. When injecting liquid, the injection port 1222 can be opened without forcibly disassembling the sealing assembly 120, which can avoid damage to the end cover 110 and the sealing assembly 120 due to forcible disassembly of the sealing assembly 120, thereby ensuring the sealing reliability.

[0062] It should be noted that the injection process of the battery cell 200 usually includes primary injection and secondary injection. Among them, after the first injection, the battery cell 200 needs to be formed so that the electrolyte penetrates into the interior of the battery cell 200 to perform a chemical reaction and realize the conversion of chemical energy into electrical energy; the secondary injection is the process of replenishing the electrolyte after the formation. Therefore, the secondary injection referred to here refers to the process of replenishing the electrolyte to the battery cell 200 after the battery cell 200 is formed, and does not limit the number of injections or the injection order, and should not be understood as injecting twice during injection, nor should it be understood as the second injection.

[0063] Please continue reading Figure 2 , Figure 4 and Figure 5, Further, the sealing assembly 120 further includes a first elastic member 125. The first elastic member 125 connects the plugging assembly 123 and the first fixing member 121. The first elastic member 125 is telescopic in the direction from the plugging assembly 123 to the first fixing member 121. When the end cap assembly 100 is in the first state, the dimension of the first elastic member 125 in the direction from the plugging assembly 123 to the first fixing member 121 is d1; when the end cap assembly 100 is in the second state, the dimension of the first elastic member 125 in the direction from the plugging assembly 123 to the first fixing member 121 is d2, where d2 > d1.

[0064] Specifically, please refer to Figure 4 . When the end cap assembly 100 is in the first state, the first elastic member 125 is in a natural state or a stretched state. When the battery cell 200 needs to be filled with liquid, the end cap assembly 100 needs to switch from the first state to the second state: an external force is applied to the driving assembly 124, and the driving assembly 124 pushes a part of the plugging assembly 123 to move in a direction away from the first fixing member 121. The first elastic member 125 is stretched and in a stretched state under the drive of the plugging assembly 123 until there is a gap between the plugging assembly 123 and the hole wall 1223, and the end cap assembly 100 is in the Figure 5 second state shown in the figure, and the battery cell 200 can be filled with liquid. When the liquid filling is completed, the force applied to the driving assembly 124 is removed, and a part of the plugging assembly 123 moves in a direction close to the first fixing member 121 under the elastic force of the first elastic member 125 until the liquid injection port 1222 is sealed, and the end cap assembly 100 returns to the first state. It can be understood that by providing the first elastic member 125, the plugging assembly 123 can be automatically sealed, the liquid injection operation is convenient, and the liquid injection efficiency is high.

[0065] Please continue to refer to Figure 2 and Figure 5 . Further, the driving assembly 124 includes a driving rod 1241 and a driving block 1242. When the end cap assembly 100 is in the second state, a part of the driving rod 1241 is inserted into the third through hole 1224, the driving block 1242 is located in the second through hole 1221, and one end of the driving block 1242 is connected to the driving rod 1241 and the other end abuts against the plugging assembly 123.

[0066] Specifically, when the battery cell 200 needs to be filled with liquid, the driving rod 1241 drives the driving block 1242 to move in the second through hole 1221 under the action of an external force until the driving block 1242 abuts against the plugging assembly 123. The size of the driving block 1242 can be larger than that of the third through hole 1224 to prevent the driving rod 1241 from disengaging from the third through hole 1224, thereby improving the stability and reliability of the sealing assembly 120. Of course, in other embodiments, the size of the driving block 1242 can also be smaller than or equal to that of the third through hole 1224, and the specific size of the driving rod 1241 can be set according to different usage requirements. Here, it is not limited thereto. It can be understood that by setting the driving block 1242 to abut against the plugging assembly 123, the contact area between the driving assembly 124 and the plugging assembly 123 can be increased, facilitating the driving assembly 124 to push the plugging assembly 123 to move, so as to further improve the liquid filling efficiency.

[0067] Please refer to Figure 2 , Figure 4 and Figure 5 , further, the driving assembly 124 further includes a second elastic member 1243. The second elastic member 1243 is sleeved on the outer peripheral side of the driving rod 1241, and one end of the second elastic member 1243 is fixedly connected to the driving block 1242. The second elastic member 1243 can contract along the extending direction of the driving rod 1241. When the end cap assembly 100 is in the first state, the dimension of the elastic member along the extending direction of the driving rod 1241 is d3; when the end cap assembly 100 is in the second state, the dimension of the second elastic member 1243 along the extending direction of the driving rod 1241 is d4, where d4 > d3.

[0068] Specifically, please refer to Figure 4 , when the end cap assembly 100 is in the first state, the first elastic member 125 is set to be in a stretched state, and one end of the second elastic member 1243 facing away from the driving block 1242 is set to abut against the hole wall 1223 to be in a compressed state. At this time, a force analysis is performed on the plugging assembly 123: the plugging assembly 123 is subjected to a pulling force from the first elastic member 125 in the direction approaching the first fixing member 121. At the same time, the elastic force of the second elastic member 1243 acts on the plugging assembly 123 through the driving block 1242, such that the plugging assembly 123 is subjected to a pushing force in the direction away from the first fixing member 121. When the forces of the above two are balanced, the plugging assembly 123 exactly seals the liquid filling port 1222. Please continue to refer to Figure 4, taking the two sets of driving components 124 as an example, and the two sets of driving components 124 are symmetrically arranged with respect to the plugging component 123. The driving component 124 includes two second elastic members 1243. When the end cover assembly 100 is in the first state, the plugging component 123 is subjected to a thrust from the two second elastic members 1243 in a direction away from the first fixing member 121 and a pulling force from the first elastic member 125 in a direction close to the first fixing member 121. When the three forces are balanced, the plugging component 123 seals the liquid injection port 1222.

[0069] Please refer to Figure 5 , when it is necessary to open the liquid injection port 1222, an external force is applied to the driving component 124, and the driving block 1242 moves in a direction away from the hole wall 1223, and the second elastic member 1243 is separated from the hole wall 1223 and is in a natural state. The external force acts on the plugging component 123 through the driving block 1242. The plugging component 123 is subjected to a thrust in a direction away from the first fixing member 121, and the first elastic member 125 is further stretched under the drive of the plugging component 123 and remains in a stretched state. When the thrust of the external force acting on the plugging component 123 is greater than the pulling force of the plugging component 123 from the second elastic member 1243 in a direction close to the first fixing member 121, the liquid injection port 1222 is opened. When it is necessary to reseal the liquid injection port 1222, only the external force applied to the driving component 124 needs to be removed.

[0070] It can be understood that if the plugging component 123 is further extended into the second through hole 1221 under the influence of other external forces, the distance between the plugging component 123 and the liquid injection port 1222 is too far, which will increase the difficulty of applying force to the driving component 124 to open the liquid injection port 1222, and even the situation where the plugging component 123 is completely separated from the hole wall 1223 and the sealing fails may occur. Therefore, by setting the second elastic member 1243 to cooperate with the first elastic member 125, the position of the plugging component 123 in the second through hole 1221 can be further controlled, and the reliability of the sealing component 120 can be improved.

[0071] Please refer to Figure 2 , Figure 4 and Figure 5, in some embodiments of the present application, the second through hole 1221 includes a first hole section 1221a and a second hole section 1221b arranged in sequence. The first hole section 1221a is arranged adjacent to the liquid injection port 1222. A step surface 1221c facing the liquid injection port 1222 is formed between the first hole section 1221a and the second hole section 1221b. When the end cap assembly 100 is in the first state, at least part of the plugging assembly 123 abuts against the step surface 1221c; when the end cap assembly 100 is in the second state, there is a gap between the plugging assembly 123 and the step surface 1221c.

[0072] Specifically, when the end cap assembly 100 switches from the second state to the first state, the plugging assembly 123 moves in a direction close to the first fixing member 121 under the elastic force from the first elastic member 125 until part of the plugging assembly 123 abuts against the step surface 1221c, and the plugging assembly 123 stops moving. It can be understood that by setting the step surface 1221c, not only can the plugging assembly 123 be prevented from further extending into the second through hole 1221, resulting in a sealing failure, but also by setting the step surface 1221c, the flow path of the electrolyte can be increased, the contact area between the plugging assembly 123 and the hole wall 1223 can be increased, and the sealing effect can be further improved.

[0073] Please continue to refer to Figure 2 , Figure 4 and Figure 5 , further, the sealing assembly 120 further includes a sealing ring 126. The sealing ring 126 is arranged in the third through hole 1224, and at least part of the driving rod 1241 passes through the sealing ring 126. Specifically, the sealing ring 126 can be but is not limited to fluororubber, polypropylene, etc. It can be understood that by setting the sealing ring 126, the sealing of the third through hole 1224 can be further realized, and the electrolyte can be prevented from flowing out from the third through hole 1224, thereby affecting the sealing performance of the sealing assembly 120.

[0074] Please refer to Figure 6 , Figure 6 For Figure 2 the three-dimensional schematic diagram of the driving block in

[0075] Please refer to togetherFigure 2 , Figure 4 and Figure 5 Further, the sealing component 123 includes a first sealing member 1231 and a connecting member 1232, the connecting member 1232 is connected to the first elastic member 125, and there is a gap between the outer peripheral side surface of the connecting member 1232 and the hole wall 1223, the first sealing member 1231 is arranged on the side of the connecting member 1232 away from the first elastic member 125, when the end cover assembly 100 is in the first state, the first sealing member 1231 abuts against the hole wall 1223 to seal the injection port 1222; when the end cover assembly 100 is in the second state, there is a gap between the first sealing member 1231 and the hole wall 1223.

[0076] It can be understood that the first blocking member 1231 is used to seal the injection port 1222, and the connecting member 1232 is used to connect with the first elastic member 125 and abut against the driving assembly 124 to drive the first blocking member 1231 to move. When the end cap assembly 100 is in the second state, the gap between the first blocking member 1231 and the hole wall 1223 and the gap between the outer peripheral side of the connecting member 1232 and the hole wall 1223 together form an electrolyte flow channel to allow electrolyte to enter the battery cell 200. Therefore, by providing a gap between the outer peripheral side of the connecting member 1232 and the hole wall 1223, the blocking assembly 123 does not need to be completely exposed in the second through hole 1221 to open the injection port 1222, thereby further improving the injection efficiency of the battery cell 200.

[0077] Please continue reading Figure 2 , Figure 4 and Figure 5 Furthermore, the sealing component 123 also includes a second sealing member 1233, which is arranged between the first sealing member 1231 and the connecting member 1232, and the second sealing member 1233 is deformable. When the end cover assembly 100 is in the first state, the second sealing member 1233 is interference fit with the hole wall 1223 to seal the injection port 1222; when the end cover assembly 100 is in the second state, there is a gap between the second sealing member 1233 and the hole wall 1223.

[0078] Specifically, the second blocking member 1233 may be, but is not limited to, fluororubber, polypropylene, etc. It is understandable that by providing the second blocking member 1233 with an interference fit with the hole wall 1223, the electrolyte can be further prevented from flowing out from the connection between the blocking component 123 and the hole wall 1223, thereby improving the sealing performance of the sealing component 120.

[0079] Please continue to refer to Figure 5 , further, the connecting member 1232 includes a first section 1232a and a second section 1232b. The second section 1232b is connected to the first elastic member 125. The first section 1232a is located on a side of the second section 1232b away from the first elastic member 125, and the diameter of the second section 1232b gradually decreases in a direction away from the first section 1232a. When the end cap assembly 100 is in the second state, the second section 1232b abuts against the driving assembly 124.

[0080] It can be understood that by setting the diameter of the second section 1232b to gradually decrease in a direction away from the first section 1232a, when the driving assembly 124 acts on the connecting member 1232, a force in a direction from the connecting member 1232 to the first sealing member 1231 can be generated, thereby improving the reliability of the sealing assembly 120. Further, a surface of a driving block 1242 of the driving assembly 124 that abuts against the connecting member 1232 is an inclined surface that closely adheres to an outer peripheral side surface of the connecting member 1232, so as to ensure the contact area between the driving assembly 124 and the connecting member 1232, and further improve the reliability of the sealing assembly 120.

[0081] Please refer to together Figure 2 and Figure 4 , further, the connecting member 1232 has a through hole 1232c penetrating through the connecting member 1232. The first fixing member 121 includes a first body portion 1212 and an extension portion 1213 extending toward the connecting member 1232. The extension portion 1213 is located in the through hole, and the first elastic member 125 is sleeved on an outer peripheral side of the extension portion 1213.

[0082] It can be understood that by providing the through hole 1232c, the connection reliability between the connecting member 1232 and the first fixing member 121 can be improved. And since the first elastic member 125 is sleeved on the outer peripheral side of the extension portion 1213, the first elastic member 125 is not easily deformed, so that the connecting member 1232 can move in a preset direction, thereby further improving the reliability of the sealing assembly 120.

[0083] Please refer to Figure 2, Further, the first fixing member 121 further includes a second body portion 1214 connected to the extension portion 1213, and a connecting portion 1215 connecting the second body portion 1214 and the first body portion 1212. The first body portion 1212, the second body portion 1214, and the connecting portion 1215 together define the first through hole 1211. It can be understood that by providing the second body portion 1214 and the connecting portion 1215 to form the first through hole 1211, while ensuring the smooth inflow of the electrolyte into the battery cell 200, the structural stability of the first fixing member 121 can be improved.

[0084] Please continue to refer to Figure 2 , Further, the first fixing member 121 includes a plurality of connecting portions 1215. The plurality of connecting portions 1215 are spaced between the second body portion 1214 and the first body portion 1212. The first body portion 1212, the second body portion 1214, and the plurality of connecting portions 1215 together define a plurality of the first through holes 1211. It can be understood that by providing the plurality of connecting portions 1215, the structural stability of the first fixing member 121 can be further improved, and the plurality of connecting portions 1215 can be prevented from breaking under the elastic force of the first elastic member 125, resulting in the separation of the second body portion 1214 and the extension portion 1213 from the first body portion 1212, causing the sealing assembly 120 to fail.

[0085] Please refer to together Figure 7 and Figure 8 , Figure 7 is a three-dimensional schematic diagram of a battery cell provided by an embodiment of the present application; Figure 8 is Figure 7 a three-dimensional exploded view of the battery cell provided. An embodiment of the second aspect of the present application provides a battery cell 200. The battery cell 200 includes a housing 210 and an end cap assembly 100. The housing 210 has an opening 211, and the end cap assembly 100 covers the opening 211. For the introduction of the end cap assembly 100, please refer to the descriptions in the previous embodiments, and details will not be repeated here.

[0086] It can be understood that when the electrolyte in the battery cell 200 is consumed to the point where it cannot be used normally, by adopting the end cap assembly 100 of the present application, the electrolyte can be added to the inside of the battery cell 200 in a timely manner, and the injection hole 111 can be resealed after the secondary injection is completed, realizing repeated injection to extend the service life of the battery cell 200, and the injection operation is simple and the injection efficiency is high.

[0087] References to "embodiments" or "implementation manners" in this application mean that specific features, structures, or characteristics described in connection with the embodiments may be included in at least one embodiment of this application. The phrase appearing at various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments. In addition, it should also be understood that the features, structures, or characteristics described in each embodiment of this application may be arbitrarily combined with each other without contradiction to form another embodiment that does not depart from the spirit and scope of the technical solution of this application.

[0088] Finally, it should be noted that the above implementation manners are only used to illustrate the technical solutions of this application and not to limit them. Although the technical solutions of this application have been described in detail with reference to the above preferred implementation manners, those of ordinary skill in the art should understand that modifications or equivalent replacements can be made to the technical solutions of this application without departing from the spirit and scope of the technical solutions of this application.

Claims

1. An end cap assembly, characterized in that, The end cap assembly includes an end cap and a sealing assembly. The end cap has a liquid injection hole, and the sealing assembly is used to seal the liquid injection hole. The end cap assembly has a first state and a second state. The sealing assembly includes: A first fixing member, which is installed in the liquid injection hole, and the first fixing member has a first through hole communicating with the liquid injection hole; A second fixing member, which is stacked with the first fixing member. The second fixing member has a second through hole penetrating the second fixing member. The second through hole forms a liquid injection port at one end of the second fixing member facing away from the first fixing member. The second through hole communicates with the first through hole. The second fixing member has a hole wall forming the second through hole and a third through hole penetrating the hole wall. The third through hole communicates with the second through hole; A plugging assembly, which is used to seal the liquid injection port; A driving assembly, at least part of which can pass through the third through hole; When the end cap assembly is in the first state, part of the plugging assembly abuts against the hole wall to seal the liquid injection port; when the end cap assembly is in the second state, part of the driving assembly passes through the third through hole, and one end of the driving assembly is located in the second through hole and abuts against the plugging assembly, and there is a gap between the plugging assembly and the hole wall; Wherein, the second through hole includes a first hole section and a second hole section arranged in sequence. The first hole section is adjacent to the liquid injection port, and a step surface facing the liquid injection port is formed between the first hole section and the second hole section. When the end cap assembly is in the first state, at least part of the plugging assembly abuts against the step surface; when the end cap assembly is in the second state, there is a gap between the plugging assembly and the step surface.

2. The end cap assembly according to claim 1, characterized in that, The sealing assembly further includes a first elastic member, which connects the plugging assembly and the first fixing member. The first elastic member is telescopable along the direction from the plugging assembly to the first fixing member. When the end cap assembly is in the first state, the dimension of the first elastic member along the direction from the plugging assembly to the first fixing member is d1; when the end cap assembly is in the second state, the dimension of the first elastic member along the direction from the plugging assembly to the first fixing member is d2, where d2 > d1.

3. The end cap assembly according to claim 2, characterized in that, The driving assembly includes a driving rod and a driving block. When the end cap assembly is in the second state, part of the driving rod passes through the third through hole, the driving block is located in the second through hole, and one end of the driving block is connected to the driving rod and the other end abuts against the plugging assembly.

4. The end cap assembly according to claim 3, wherein The driving assembly further includes a second elastic member sleeved on the outer peripheral side of the driving rod. One end of the second elastic member is fixedly connected to the driving block, and the second elastic member can be contracted along the extending direction of the driving rod. When the end cover assembly is in the first state, the dimension of the elastic member along the extending direction of the driving rod is d3; when the end cover assembly is in the second state, the dimension of the second elastic member along the extending direction of the driving rod is d4, where d4 > d3.

5. The end cap assembly according to any one of claims 3 or 4, characterized in that, The sealing assembly further includes a sealing ring disposed in the third through hole, and at least a part of the driving rod penetrates through the sealing ring.

6. The end cap assembly according to any one of claims 3 or 4, characterized in that One end of the driving block close to the driving rod has a groove, and one end of the driving rod is located in the groove.

7. The end cap assembly according to claim 2, characterized in that, The plugging assembly includes a first plugging member and a connecting member connected to the first elastic member. There is a gap between the outer peripheral side surface of the connecting member and the hole wall. The first plugging member is disposed on the side of the connecting member away from the first elastic member. When the end cover assembly is in the first state, the first plugging member abuts against the hole wall to seal the liquid injection port; when the end cover assembly is in the second state, there is a gap between the first plugging member and the hole wall.

8. The end cap assembly according to claim 7, wherein, The plugging assembly further includes a second plugging member disposed between the first plugging member and the connecting member. The second plugging member is deformable. When the end cover assembly is in the first state, the second plugging member is in interference fit with the hole wall to seal the liquid injection port; when the end cover assembly is in the second state, there is a gap between the second plugging member and the hole wall.

9. The end cap assembly according to claim 7, characterized in that, The connecting member includes a first section and a second section. The second section is connected to the first elastic member. The first section is located on the side of the second section away from the first elastic member, and the diameter of the second section gradually decreases in the direction away from the first section. When the end cover assembly is in the second state, the second section abuts against the driving assembly.

10. The end cap assembly according to claim 7, characterized in that, The connecting member has a through hole penetrating through the connecting member. The first fixing member includes a first body portion and an extending portion extending towards the connecting member. The extending portion is located in the through hole, and the first elastic member is sleeved on the outer peripheral side of the extending portion.

11. The end cap assembly according to claim 10, wherein The first fixing member further includes a second body portion connected to the extending portion and a connecting portion connecting the second body portion and the first body portion. The first body portion, the second body portion and the connecting portion jointly define the first through hole.

12. The end cap assembly according to claim 11, wherein The first fixing member includes a plurality of connecting portions spaced between the second body portion and the first body portion. The first body portion, the second body portion and the plurality of connecting portions jointly define a plurality of the first through holes.

13. A battery cell, characterized in that Comprising: A housing having an opening; The end cover assembly according to any one of claims 1 to 12, the end cover assembly covering the opening.

Images