Current collector, battery cell and battery pack

Abstract

The present application provides a current collecting assembly, a battery cell and a battery pack. The current collecting assembly includes: a connector, the connector having a first surface, a second surface and a peripheral side surface, the second surface is arranged opposite to the first surface, the peripheral side surface is bent and connected between the first surface and the second surface, the connector also has a first injection hole that passes through the first surface and the second surface, and a first channel that connects the first injection hole with at least one opening formed on the peripheral side surface; a current collecting member, the current collecting member is arranged adjacent to the second surface, and the current collecting member is connected to the connector, the current collecting member has a second injection hole, and the second injection hole is connected to the first injection hole. The current collecting assembly, battery cell and battery pack provided in the present application can effectively shorten the exhaust path inside the battery cell, and improve the injection efficiency of the battery cell and the electrolyte infiltration efficiency, thereby improving the production efficiency of the battery cell.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a current collecting assembly, a battery cell and a battery pack. Background Art

[0002] During the production of secondary batteries, electrolyte needs to be injected into the battery cells. Existing battery cells are injected in the form of positive and negative pressure cycles. When the battery cell is in a negative pressure state, the air pressure inside the battery cell is lower than the air pressure in the space where the electrolyte is located. A pressure difference is formed between the battery cell and the space where the electrolyte is located, and the electrolyte is injected into the battery cell with the help of pressure. In order to put the battery cell in a negative pressure state, the battery cell needs to be evacuated. Since the existing battery cells contain current collectors and electrode assemblies, the evacuation path inside the battery cell is tortuous and complex, and the evacuation efficiency is low, which in turn affects the electrolyte injection efficiency and the production efficiency of the battery cell. Summary of the invention

[0003] In response to the above problems, the embodiments of the present application provide a current collecting assembly, a battery cell and a battery pack, which can effectively shorten the exhaust path inside the battery cell and improve the injection efficiency and electrolyte infiltration efficiency of the battery cell, thereby improving the production efficiency of the battery cell.

[0004] A first aspect of the present application provides a current collecting assembly, the current collecting assembly comprising:

[0005] A connecting member, the connecting member having a first surface, a second surface and a peripheral side surface, the second surface being disposed opposite to the first surface, the peripheral side surface being bent and connected between the first surface and the second surface, the connecting member further having a first injection hole penetrating through the first surface and the second surface, and a first channel connecting the first injection hole with at least one opening formed on the peripheral side surface; and

[0006] A current collecting member is disposed adjacent to the second surface and connected to the connecting member. The current collecting member has a second liquid injection hole, and the second liquid injection hole is connected to the first liquid injection hole.

[0007] When the current collecting assembly is applied to a battery cell, on the one hand, the current collecting assembly is provided with a first injection hole, so that the injection position of the battery cell is integrated on the current collecting assembly, thereby making the overall structure of the battery cell more compact and more convenient for injecting electrolyte into the battery cell. On the other hand, since the air extraction path between the end cover and the current collecting piece is long, the extraction efficiency is low. By providing the first channel, the first channel is connected to the first injection hole, and the air between the end cover and the current collecting piece can be directly extracted to the outside of the battery cell through the first channel, effectively shortening the extraction path, improving the extraction efficiency, and thus improving the production efficiency of the battery cell.

[0008] Furthermore, the first channel is a depression formed in the direction of the second surface.

[0009] In an embodiment of the present application, by arranging the first channel on the second surface, the processing of the first channel is facilitated, thereby improving the processing efficiency of the current collecting assembly.

[0010] Furthermore, the first channel passes through the peripheral side surface and connects the first liquid injection hole with two openings formed on the peripheral side surface.

[0011] In an embodiment of the present application, by setting the first channel to pass through the peripheral side surface and connecting the first liquid injection hole with two openings formed on the peripheral side surface, it is convenient for the air between the end cover and the current collecting member to enter the first liquid injection hole through the two openings at the same time, thereby further improving the air extraction efficiency of the battery cell.

[0012] In some embodiments of the present application, the connecting member includes a first body portion and a first positioning portion, the first body portion has the first liquid injection hole and the first channel, and the first positioning portion is disposed on the first body portion;

[0013] The current collecting member includes a second main body and a second positioning portion, the second main body has the second liquid injection hole, the second positioning portion is arranged on the second main body, and the second positioning portion cooperates with the first positioning portion to connect the current collecting member to the connecting member.

[0014] In an embodiment of the present application, the connector is positioned on the current collecting member by the cooperation of the second positioning portion and the first positioning portion, and then the connector is fixedly connected to the current collecting member by welding. Because the connector and the current collecting member have been positioned by the cooperation of the second positioning portion and the first positioning portion before the connector and the current collecting member are welded, the welding position can be accurately identified during welding, thereby effectively improving the welding efficiency.

[0015] Further, the first positioning portion includes two positioning columns, the two positioning columns are arranged on the second surface, and the two positioning columns are respectively arranged on both sides of the first channel, and the second positioning portion includes two positioning holes, and the two positioning columns are respectively inserted into the two positioning holes.

[0016] In an embodiment of the present application, by setting the first positioning portion as a positioning column and the second positioning portion as a positioning hole, and inserting the positioning column into the positioning hole, the connecting member can be accurately positioned on the current collecting member, and by respectively setting the two positioning columns on both sides of the first channel and inserting them into the two positioning holes, the stability and reliability of the assembly of the current collecting assembly can be improved.

[0017] Furthermore, the first positioning portion is a positioning column, the second positioning portion is a positioning hole, the positioning hole is a through hole, the positioning column is inserted into the through hole, and the current collecting member also includes at least one connecting portion, the connecting portion protrudes from the side of the second main body portion away from the connecting member, and the end surface of the connecting portion away from the second main body portion is flush with the end surface of the first positioning portion away from the first main body portion or is farther away from the second main body portion than the end surface of the first positioning portion away from the first main body portion.

[0018] In an embodiment of the present application, by arranging the end face of the connecting portion facing away from the second main body portion to be flush with the end face of the first positioning portion facing away from the first main body portion or to be further away from the second main body portion than the end face of the first positioning portion facing away from the first main body portion, it is possible to avoid the first positioning portion from abutting against the electrode assembly, thereby affecting the connection effect between the connecting portion and the electrode assembly.

[0019] Furthermore, the first liquid injection hole extends from the geometric center of the first surface of the connector to the geometric center of the second surface, the second liquid injection hole is located at the geometric center of the current collecting piece, the current collecting piece includes a plurality of connecting parts, the current collecting piece has a central area, the geometric center of the current collecting piece and the second positioning part are located in the central area, the plurality of connecting parts are arranged around the central area and extend from the central area to the periphery of the current collecting piece.

[0020] In the embodiment of the present application, the first injection hole is arranged to extend from the geometric center of the first surface of the connector to the geometric center of the second surface, and the second injection hole is located at the geometric center of the current collector, so as to facilitate the positioning and assembly between the connector and the current collector. By arranging the multiple connecting parts to surround the central area and extend from the central area to the periphery of the current collector, it is possible to ensure that the current collector is effectively connected to the tabs at multiple positions on the end surface of the electrode assembly close to the current collector, thereby achieving sufficient conduction of current and improving the reliability of the battery cell.

[0021] Furthermore, the second main body portion has a plurality of through holes, and the plurality of through holes are located between any two adjacent connecting portions.

[0022] In the embodiment of the present application, by providing the through hole, when the battery cell undergoes thermal runaway, the gas generated by the electrode assembly can be discharged into the space between the end cover and the current collecting member through the through hole, thereby achieving pressure release.

[0023] In some embodiments of the present application, at least one guide groove is provided on a surface of the current collecting member facing away from the connecting member, the guide groove is connected to the second liquid injection hole, and the guide groove extends from the second liquid injection hole to the periphery of the current collecting member.

[0024] In an embodiment of the present application, by providing the guide groove connected to the second injection hole, after the electrolyte is injected through the second injection hole, it flows along the guide groove to the periphery of the current collecting component, so that the end face of the electrode assembly close to the current collecting assembly is in timely and sufficient contact with the electrolyte, thereby improving the electrolyte infiltration efficiency and infiltration effect.

[0025] In some embodiments of the present application, the current collecting member includes a second main body portion and at least one supporting portion, wherein the supporting portion is arranged at the periphery of the second main body portion and is located on the side of the second main body portion facing the connecting member, and along the thickness direction of the second main body portion, the height of the supporting portion is smaller than the height of the connecting member.

[0026] In the embodiment of the present application, by providing the support portion, the support portion can support the second body portion, thereby preventing the current collecting assembly from being deformed and causing safety problems of the battery cell.

[0027] A second aspect of the present application provides a battery cell, wherein the battery cell comprises:

[0028] A shell, the shell comprising a receiving cavity and an opening;

[0029] an electrode assembly, the electrode assembly being accommodated in the accommodation cavity;

[0030] An end cover, the end cover covers the opening;

[0031] At least one current collecting component, the connecting portion is connected to the end cover, a second channel is formed between the current collecting component and the end cover, and the second channel is connected to the first channel. Please refer to the introduction of the previous embodiments of the current collecting component, which will not be repeated here.

[0032] In an embodiment of the present application, by forming the second channel between the current collector and the end cover, when the battery cell has thermal runaway, the gas generated by the electrode assembly can enter the second channel, thereby achieving pressure release. The second channel is connected to the first channel, and when the battery cell is evacuating gas, the gas in the second channel can be directly connected to the first injection hole through the first channel, and then the gas in the second channel is discharged to the outside of the battery cell, thereby improving the evacuation efficiency.

[0033] Furthermore, the end cover is provided with a mounting hole; the connecting member includes a first section and a second section, the first section is inserted into the mounting hole to be connected to the end cover, and at least a portion of the surface of the first section is exposed to the end cover, the second section is abutted against the end cover at one end close to the first section, and is connected to the current collecting member at one end away from the first section, and the second section separates the end cover from the current collecting member to form the second channel.

[0034] On the one hand, at least part of the surface of the first section is exposed to the end cover, so that the first injection hole is connected to the outside of the battery cell, which is convenient for extracting the gas inside the battery cell to the outside of the battery cell. On the other hand, when the current collecting assembly and the end cover are connected by welding, at least part of the surface of the first section is exposed to the end cover, so that the welding position of the current collecting assembly and the end cover is located outside the battery cell, which is convenient for confirming the welding position of the current collecting assembly and the end cover, thereby improving the welding efficiency and welding effect.

[0035] A third aspect of the present application provides a battery pack, the battery pack comprising:

[0036] Box, and

[0037] At least one battery cell is contained in the box. Please refer to the introduction of the above embodiments for the battery cell, which will not be described here.

[0038] The battery pack effectively improves production efficiency and safety by adopting the battery cells described in each embodiment of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 is a three-dimensional schematic diagram of a current collecting assembly provided in one embodiment of the present application;

[0041] Figure 2 yes Figure 1 A perspective exploded view of the current collecting assembly shown;

[0042] Figure 3 yes Figure 1 A three-dimensional schematic diagram of a connecting member in FIG.

[0043] Figure 4 yes Figure 1 A top view of the current collecting assembly shown;

[0044] Figure 5 yes Figure 4 The cross-sectional diagram along the AA line in FIG.

[0045] Figure 6 yes Figure 1 A bottom view of the current collecting assembly is shown;

[0046] Figure 7 is a three-dimensional schematic diagram of a battery cell provided in one embodiment of the present application;

[0047] Figure 8 yes Figure 7 A perspective exploded view of a battery cell is shown;

[0048] Fig. 9 yes Figure 7 The cross-sectional diagram along line BB in FIG.

[0049] Fig.10 It is a three-dimensional schematic diagram of a battery pack provided in one embodiment of the present application.

[0050] Description of reference numerals:

[0051] 100-battery cells,

[0052] 110-housing, 111-accommodating cavity, 112-opening,

[0053] 120-electrode assembly, 121-center hole,

[0054] 130-end cover, 131-mounting hole,

[0055] 140-current collecting component, 141-connecting member, 1411-first surface, 1412-second surface, 1413-side surface, 1414-first liquid injection hole, 1415-first channel, 1415a-opening, 1416-first body, 1417-first positioning portion, 1418-first section, 1419-second section, 142-current collecting member, 1421-second liquid injection hole, 1422-second body, 1423-second positioning portion, 1424-connecting portion, 1425-central area, 1426-through hole, 1427-guiding groove, 1428-support portion,

[0056] 150-Second channel;

[0057] 200-battery pack, 210-box. DETAILED DESCRIPTION

[0058] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0059] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0060] It should be noted that, for the convenience of explanation, in the embodiments of the present application, the same figure marks represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments.

[0061] Please also read Figures 1 to 3 , Figure 1 is a three-dimensional schematic diagram of a current collecting assembly provided in one embodiment of the present application; Figure 2 yes Figure 1 A perspective exploded view of the current collecting assembly shown; Figure 3 yes Figure 1A three-dimensional schematic diagram of the connector in the embodiment of the first aspect of the present application provides a current collecting component 140, and the current collecting component 140 includes a connecting member 141 and a current collecting member 142. The connecting member 141 has a first surface 1411, a second surface 1412 and a peripheral side surface 1413. The second surface 1412 is arranged opposite to the first surface 1411, and the peripheral side surface 1413 is bent and connected between the first surface 1411 and the second surface 1412. The connecting member 141 also has a first injection hole 1414 that passes through the first surface 1411 and the second surface 1412, and a first channel 1415 that connects the first injection hole 1414 with at least one opening 1415a formed on the peripheral side surface 1413. That is, the connecting member 141 also has a first channel 1415 with an opening 1415a located on the peripheral side surface 1413, and the first channel 1415 is connected to the first injection hole 1414. The current collecting member 142 is disposed adjacent to the second surface 1412 and connected to the connecting member 141 . The current collecting member 142 has a second liquid injection hole 1421 . The second liquid injection hole 1421 is communicated with the first liquid injection hole 1414 .

[0062] It should be noted that the current collecting assembly 140 described in the embodiment of the present application can be applied to the battery cell 100 (see Figure 8 ), and each embodiment of the present application is described by taking the current collecting assembly 140 applied to the battery cell 100 as an example. Of course, in other embodiments, the current collecting assembly 140 described in the present application can also be applied to other scenarios requiring current collection or current diversion, and the use scenario of the current collecting assembly 140 described in the present application is not limited here.

[0063] Specifically, in some embodiments of the present application, the battery cell 100 includes an end cap 130 and an electrode assembly 120 (see 8), and the electrode assembly 120 has a center hole 121 that penetrates the electrode assembly 120 and is located at the center of the electrode assembly 120. The current collecting assembly 140 is installed between the end cap 130 and the electrode assembly 120, and is used to achieve electrical connection between the end cap 130 and the electrode assembly 120. Of course, in some other embodiments, the current collecting assembly 140 can also be used to achieve electrical connection between the electrode assembly 120 and an electrical connector (not shown) outside the battery cell 100, and the electrical connector is used to achieve series-parallel connection between multiple battery cells 100. At this time, the current collecting assembly 140 is insulated from the end cap 130.

[0064] Please also read Figure 4 and Figure 5 , Figure 4 yes Figure 1A top view of the current collecting assembly shown; Figure 5 yes Figure 4 Schematic cross-sectional view along line AA in . When the battery cell 100 is injected with electrolyte, the electrolyte flows through the first injection hole 1414 and the second injection hole 1421 in sequence, and then enters the central hole 121 (see 8), and infiltrates the electrode assembly 120. In order to form a pressure difference between the interior of the battery cell 100 and the space where the electrolyte is located, so that the electrolyte can enter the interior of the battery cell 100 with the help of the pressure difference, it is necessary to evacuate the battery cell 100 so that the battery cell 100 is in a negative pressure state. When the battery cell 100 is evacuated, the evacuation path of the air between the end cover 130 and the current collector 142 is: from the side of the electrode assembly 120, enter the central hole 121 of the electrode assembly 120, and pass through the second injection hole 1421 and the first injection hole 1414 in sequence, and then be evacuated to the outside of the battery cell 100.

[0065] Therefore, on the one hand, the current collecting assembly 140 described in the present application is provided with a first injection hole 1414, so that the injection position of the battery cell 100 is integrated on the current collecting assembly 140, so that the overall structure of the battery cell 100 is more compact and it is more convenient to inject the electrolyte into the battery cell 100. On the other hand, since the path of the air between the end cover 130 and the current collecting piece 142 to the first injection hole 1414 is long, if the battery cell 100 is directly evacuated from the first injection hole 1414, the evacuation efficiency will be low. The current collecting assembly 140 provided in the embodiment of the present application is provided with the first channel 1415, and the first channel 1415 is connected to the first injection hole 1414. The air between the end cover 130 and the current collecting piece 142 can be directly evacuated to the outside of the battery cell 100 through the first channel 1415, effectively shortening the evacuation path, improving the evacuation efficiency, and thus improving the production efficiency of the battery cell 100.

[0066] Please continue reading Figure 3 In some embodiments of the present application, the first channel 1415 is a depression formed on the second surface 1412. That is, the second surface 1412 is depressed toward the first surface 1411 to form the first channel 1415. It can be understood that by arranging the first channel 1415 on the second surface 1412, the processing of the first channel 1415 is facilitated, thereby improving the processing efficiency of the current collecting assembly 140.

[0067] Specifically, the cross section of the first channel 1415 along the thickness direction of the connecting member 141 may be semicircular. When the cross section of the first channel 1415 is semicircular, the diameter of the first channel 1415 may be set to be greater than or equal to the diameter of the first injection hole 1414. By setting the cross section of the first channel 1415 to be semicircular, the processing of the first channel 1415 can be facilitated; by setting the diameter of the first channel 1415 to be greater than or equal to the diameter of the first injection hole 1414, the gas extraction efficiency of the battery cell 100 can be further improved, and the injection efficiency of the battery cell 100 and the electrolyte infiltration effect after injection can be further improved. Of course, in other embodiments, the diameter of the first channel 1415 may also be smaller than the diameter of the first injection hole 1414. In other embodiments, the cross section of the first channel 1415 along the extension direction of the first injection hole 1414 may also be any other shape, for example, an arc, a rectangle, a triangle, or other irregular shapes.

[0068] Further, the first channel 1415 passes through the peripheral side surface 1413, and connects the first injection hole 1414 with the two openings 1415a formed on the peripheral side surface 1413. That is, the first channel 1415 passes through the peripheral side surface 1413 to form the two openings 1415a on the peripheral side surface 1413, so that the first injection hole 1414 is connected with the two openings 1415a. It can be understood that by setting the first channel 1415 to pass through the peripheral side surface 1413 and connecting the first injection hole 1414 with the two openings 1415a formed on the peripheral side surface 1413, it is convenient for the air between the end cover 130 and the current collecting member 142 to enter the first injection hole 1414 through the two openings 1415a at the same time, thereby further improving the air extraction efficiency of the battery cell 100.

[0069] Please also read Figure 2 and Figure 3 In some embodiments of the present application, the connecting member 141 includes a first body portion 1416 and a first positioning portion 1417, the first body portion 1416 has the first injection hole 1414 and the first channel 1415, and the first positioning portion 1417 is disposed on the first body portion 1416. The current collecting member 142 includes a second body portion 1422 and a second positioning portion 1423, the second body portion 1422 has the second injection hole 1421, the second positioning portion 1423 is disposed on the second body portion 1422, and the second positioning portion 1423 cooperates with the first positioning portion 1417 to connect the current collecting member 142 to the connecting member 141.

[0070] Specifically, the connector 141 is positioned on the current collecting member 142 by the cooperation of the second positioning portion 1423 and the first positioning portion 1417, and then the connector 141 is fixedly connected to the current collecting member 142. For example, the connector 141 and the current collecting member 142 may be fixedly connected by, but not limited to, welding or bonding. Since the connector 141 and the current collecting member 142 have been positioned by the cooperation of the second positioning portion 1423 and the first positioning portion 1417 before the connector 141 and the current collecting member 142 are welded, the welding position can be accurately identified during welding, thereby effectively improving the welding efficiency.

[0071] It is understandable that in some other embodiments, the connector 141 and the current collecting member 142 may also be an integral structure, that is, the current collecting assembly 140 is an integrally formed component, so as to reduce the processing steps of the current collecting assembly 140 and improve the processing efficiency of the battery cell 100 .

[0072] Furthermore, the first positioning portion 1417 includes two positioning columns, the two positioning columns are arranged on the second surface 1412, and the two positioning columns are respectively arranged on both sides of the first channel 1415, and the second positioning portion 1423 includes two positioning holes, and the two positioning columns are respectively inserted into the two positioning holes.

[0073] It can be understood that by setting the first positioning portion 1417 as a positioning column and the second positioning portion 1423 as a positioning hole, and the positioning column is inserted into the through hole, the connecting member 141 can be accurately positioned on the current collecting member 142, and by respectively setting the two positioning columns on both sides of the first channel 1415 and inserting them into the two positioning holes, the stability and reliability of the assembly of the current collecting component 140 can be improved.

[0074] Please continue reading Figure 5 , further, the first positioning portion 1417 is a positioning column, the second positioning portion 1423 is a positioning hole, the positioning hole is a through hole, the positioning column is inserted into the through hole, the current collecting member 142 further comprises at least one connecting portion 1424, the connecting portion 1424 protrudes from the side of the second body portion 1422 away from the connecting member 141, and the end surface of the connecting portion 1424 away from the second body portion 1422 is flush with the end surface of the first positioning portion 1417 away from the first body portion 1416 or is further away from the second body portion 1422 than the end surface of the first positioning portion 1417 away from the first body portion 1416. That is, the end surface of the connecting portion 1424 away from the second body portion 1422 protrudes or is flush with the end surface of the first positioning portion 1417 away from the first body portion 1416.

[0075] Specifically, the connecting portion 1424 protrudes from the side of the second body portion 1422 away from the connecting member 141 to achieve the connection between the current collecting assembly 140 and the electrode assembly 120. The connecting portion 1424 is away from the end surface of the second body portion 1422, that is, along the thickness direction of the second body portion 1422, the connecting portion 1424 is the end surface farthest from the second body portion 1422; the first positioning portion 1417 is away from the end surface of the first body portion 1416, that is, along the thickness direction of the first body portion 1416, the first positioning portion 1417 is the end surface farthest from the first body portion 1416. By arranging the end surface of the connecting portion 1424 facing away from the second main body portion 1422 to be flush with the end surface of the first positioning portion 1417 facing away from the first main body portion 1416 or to be further away from the second main body portion 1422 than the end surface of the first positioning portion 1417 facing away from the first main body portion 1416, it is possible to avoid the first positioning portion 1417 from abutting against the electrode assembly 120, thereby affecting the connection effect between the connecting portion 1424 and the electrode assembly 120.

[0076] See also Figure 2 Furthermore, the first injection hole 1414 extends from the geometric center of the first surface 1411 of the connecting piece 141 to the geometric center of the second surface 1412, and the second injection hole 1421 is located at the geometric center of the current collecting piece 142. The current collecting piece 142 includes a plurality of connecting parts 1424, and the current collecting piece 142 has a central area 1425. The geometric center of the current collecting piece 142 and the second positioning part 1423 are located in the central area 1425. The plurality of connecting parts 1424 are arranged around the central area 1425 and extend from the central area 1425 to the periphery of the current collecting piece 142.

[0077] It can be understood that by setting the first injection hole 1414 to extend from the geometric center of the first surface 1411 of the connector 141 to the geometric center of the second surface 1412, the second injection hole 1421 is located at the geometric center of the current collector 142, which facilitates the positioning and assembly between the connector 141 and the current collector 142. By setting the multiple connecting parts 1424 to be arranged around the central area 1425 and extending from the central area 1425 to the periphery of the current collector 142, it can be ensured that the current collector 142 is effectively connected to the pole ears at multiple positions on the end surface of the electrode assembly 120 close to the current collector 142, thereby achieving full conduction of current and improving the reliability of the battery cell 100.

[0078] Furthermore, the second body portion 1422 has a plurality of through holes 1426, and the plurality of through holes 1426 are located between any two adjacent connecting portions 1424. It can be understood that when the battery cell 100 has thermal runaway, the gas generated by the electrode assembly 120 can be discharged into the space between the end cap 130 and the current collector 142 through the through holes 1426, thereby achieving pressure release.

[0079] Specifically, if the thermal runaway degree of the battery cell 100 is relatively mild, the amount of gas generated by the battery cell 100 is relatively small, and the gas enters the space between the end cap 130 and the current collector 142 to release the pressure, thereby avoiding the safety hazard caused by excessive internal pressure of the battery cell 100. If the thermal runaway degree of the battery cell 100 is relatively severe, the amount of gas generated by the battery cell 100 is relatively large, and the gas generated by the electrode assembly 120 enters the space between the end cap 130 and the current collector 142, and when the internal pressure of the battery cell 100 is higher than the set threshold, the gas rushes out of the explosion-proof valve (not shown) on the end cap 130 and is discharged to the outside of the battery cell 100, so as to release the internal pressure of the battery cell 100 and improve the safety of the battery cell 100.

[0080] See also Figure 6 , Figure 6 yes Figure 1 A bottom view of the current collecting assembly is shown. In some embodiments of the present application, at least one guide groove 1427 is provided on the surface of the current collecting member 142 facing away from the connecting member 141, and the guide groove 1427 is connected to the second injection hole 1421, and the guide groove 1427 extends from the second injection hole 1421 to the periphery of the current collecting assembly 140. It can be understood that since the current collecting assembly 140 is close to the electrode assembly 120, the electrolyte flows directly into the central hole 121 along the second injection hole 1421 during injection, and the end face of the electrode assembly 120 close to the current collecting assembly 140 is difficult to contact the electrolyte in time, thereby affecting the infiltration efficiency of the electrolyte. By providing the guide groove 1427 connected to the second injection hole 1421, after the electrolyte is injected through the second injection hole 1421, it flows along the guide groove 1427 to the periphery of the current collecting component 142, so that the end face of the electrode assembly 120 close to the current collecting component 140 is in timely and sufficient contact with the electrolyte, thereby improving the electrolyte infiltration efficiency and infiltration effect.

[0081] Please continue reading Figure 5In some embodiments of the present application, the current collecting member 142 includes a second main body portion 1422 and at least one supporting portion 1428, wherein the supporting portion 1428 is disposed at the periphery of the second main body portion 1422 and is located on the side of the second main body portion 1422 facing the connecting member 141, and along the thickness direction of the second main body portion 1422, the height of the supporting portion 1428 is less than the height of the connecting member 141.

[0082] It can be understood that when the current collecting assembly 140 is disposed at the bottom of the battery cell 100, that is, when the current collecting assembly 140 carries the electrode assembly 120, the current collecting assembly 140 is at risk of being squeezed and deformed due to the weight of the electrode assembly 120. By providing the support portion 1428, the support portion 1428 can support the second body portion 1422, thereby preventing the current collecting assembly 140 from deforming and causing safety problems of the battery cell 100. Of course, in some other embodiments, the current collecting assembly 140 can also be disposed at the top of the battery cell 100.

[0083] Please also read Figures 7 to 9 , Figure 7 is a three-dimensional schematic diagram of a battery cell provided in one embodiment of the present application; Figure 8 yes Figure 7 A perspective exploded view of a battery cell is shown; Fig. 9 yes Figure 7 Schematic cross-sectional view along line BB in the figure. The second embodiment of the present application provides a battery cell 100, which includes a shell 110, an electrode assembly 120, an end cover 130 and at least one current collecting assembly 140. The shell 110 includes a accommodating cavity 111 and an opening 112, the electrode assembly 120 is accommodated in the accommodating cavity 111, and the end cover 130 covers the opening 112. The connecting member 141 is connected to the end cover 130, and a second channel 150 is formed between the current collecting member 142 and the end cover 130, and the second channel 150 is connected to the first channel 1415. Please refer to the introduction of the previous embodiments for the current collecting assembly 140, which will not be repeated here.

[0084] It can be understood that by forming the second channel 150 between the current collecting assembly 140 and the end cover 130, when the battery cell 100 has thermal runaway, the gas generated by the electrode assembly 120 can enter the second channel 150, thereby achieving pressure release. If the thermal runaway degree of the battery cell 100 is relatively mild, the amount of gas generated by the battery cell 100 is small, and the gas entering the second channel 150 can achieve pressure release, thereby avoiding the safety hazard caused by excessive internal pressure of the battery cell 100. If the thermal runaway degree of the battery cell 100 is relatively severe, the amount of gas generated by the battery cell 100 is large, and the gas generated by the electrode assembly 120 passes through the second channel 150, and when the internal pressure of the battery cell 100 is higher than the set threshold, the gas rushes out of the explosion-proof valve on the end cover 130 and is discharged to the outside of the battery cell 100 to release the internal pressure of the battery cell 100 and improve the safety of the battery cell 100. The second channel 150 is connected to the first channel 1415. When the battery cell 100 is evacuating, the gas in the second channel 150 can be directly connected to the first injection hole 1414 through the first channel 1415, and then the gas in the second channel 150 is discharged to the outside of the battery cell 100, thereby improving the evacuation efficiency.

[0085] Furthermore, the end cover 130 is provided with a mounting hole 131; the connecting member 141 includes a first section 1418 and a second section 1419, the first section 1418 is inserted into the mounting hole 131 to be connected to the end cover 130, and at least part of the surface of the first section 1418 is exposed to the end cover 130, the second section 1419 is abutted against the end cover 130 at one end close to the first section 1418, and the second section 1419 is connected to the current collecting member 142 at one end away from the first section 1418, and the second section 1419 separates the end cover 130 from the current collecting member 142 to form the second channel 150.

[0086] On the one hand, at least part of the surface of the first section 1418 is exposed to the end cover 130, so that the first injection hole 1414 is connected to the outside of the battery cell 100, which is convenient for extracting the gas inside the battery cell 100 to the outside of the battery cell 100. On the other hand, when the current collector assembly 140 and the end cover 130 are connected by welding, at least part of the surface of the first section 1418 is exposed to the end cover 130, so that the welding position of the current collector assembly 140 and the end cover 130 is located outside the battery cell 100, which is convenient for confirming the welding position of the current collector assembly 140 and the end cover 130, thereby improving the welding efficiency and welding effect. Of course, in other embodiments, the connection method between the current collector assembly 140 and the end cover 130 can also be other methods besides welding, which is not limited here.

[0087] See also Fig.10 , Fig.10 : is a three-dimensional schematic diagram of a battery pack provided by an embodiment of the present application. The third aspect of the present application provides a battery pack 200, the battery pack 200 includes a box 210 and at least one battery cell 100, and the battery cell 100 is accommodated in the box 210. Please refer to the introduction of the previous embodiments for the battery cell 100, which will not be repeated here. The battery pack 200 effectively improves production efficiency and safety by adopting the battery cell 100 described in each embodiment of the present application.

[0088] Mentioning "embodiment" and "implementation method" in this application means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrases in various places 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 can be combined with other embodiments. In addition, it should also be understood that the features, structures or characteristics described in the various embodiments of the present application can be arbitrarily combined to form another embodiment that does not deviate from the spirit and scope of the technical solution of the present application, provided that there is no contradiction between them.

[0089] Finally, it should be noted that the above implementation modes are only used to illustrate the technical solution of the present application and are not intended to limit it. Although the present application has been described in detail with reference to the above preferred implementation modes, a person of ordinary skill in the art should understand that the technical solution of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present application.

Claims

1. A current collecting assembly, characterized in that: The current collecting assembly comprises: A connecting member, the connecting member having a first surface, a second surface and a peripheral side surface, the second surface being disposed opposite to the first surface, the peripheral side surface being bent and connected between the first surface and the second surface, the connecting member further having a first injection hole penetrating through the first surface and the second surface, and a first channel connecting the first injection hole with at least one opening formed on the peripheral side surface; and A current collecting member, the current collecting member is disposed adjacent to the second surface and connected to the connecting member, the current collecting member has a second liquid injection hole, and the second liquid injection hole is connected to the first liquid injection hole; Wherein, the first channel is used to draw air between the end cover and the current collecting member to the outside of the battery cell.

2. The current collecting assembly according to claim 1, characterized in that: The first channel is a depression formed in the second surface.

3. The current collecting assembly according to claim 1 or 2, characterized in that: The first channel passes through the peripheral side surface and connects the first liquid injection hole with two openings formed on the peripheral side surface.

4. The current collecting assembly according to claim 1, characterized in that: The connecting member includes a first body portion and a first positioning portion, the first body portion has the first liquid injection hole and the first channel, and the first positioning portion is disposed on the first body portion; The current collecting member includes a second main body and a second positioning portion, the second main body has the second liquid injection hole, the second positioning portion is arranged on the second main body, and the second positioning portion cooperates with the first positioning portion to connect the current collecting member to the connecting member.

5. The current collecting assembly according to claim 4, characterized in that: The first positioning portion includes two positioning columns, the two positioning columns are arranged on the second surface, and the two positioning columns are respectively arranged on both sides of the first channel, and the second positioning portion includes two positioning holes, the two positioning columns are respectively inserted into the two positioning holes.

6. The current collecting assembly according to claim 4, characterized in that: The first positioning portion is a positioning column, the second positioning portion is a positioning hole, the positioning hole is a through hole, the positioning column is inserted into the positioning hole, the current collecting member also includes at least one connecting portion, the connecting portion protrudes from the side of the second main body portion away from the connecting member, and the end surface of the connecting portion away from the second main body portion is flush with the end surface of the first positioning portion away from the first main body portion or is farther away from the second main body portion than the end surface of the first positioning portion away from the first main body portion.

7. The current collecting assembly according to claim 5 or 6, characterized in that: The first liquid injection hole extends from the geometric center of the first surface of the connector to the geometric center of the second surface, and the second liquid injection hole is located at the geometric center of the current collecting piece. The current collecting piece includes a plurality of connecting parts, and the current collecting piece has a central area. The geometric center of the current collecting piece and the second positioning part are located in the central area. The plurality of connecting parts are arranged around the central area and extend from the central area to the periphery of the current collecting piece.

8. The current collecting assembly according to claim 7, characterized in that: The second body portion has a plurality of through holes, and the plurality of through holes are located between any two adjacent connecting portions.

9. The current collecting assembly according to claim 1, characterized in that: At least one guide groove is provided on a surface of the current collecting member facing away from the connecting member. The guide groove is communicated with the second liquid injection hole and extends from the second liquid injection hole to the periphery of the current collecting component.

10. The current collecting assembly according to claim 1, characterized in that: The current collecting member includes a second main body portion and at least one supporting portion, wherein the supporting portion is arranged at the periphery of the second main body portion and is located on a side of the second main body portion facing the connecting member, and along the thickness direction of the second main body portion, the height of the supporting portion is smaller than the height of the connecting member.

11. A battery cell, characterized in that: include: A shell, the shell comprising a receiving cavity and an opening; an electrode assembly, the electrode assembly being accommodated in the accommodation cavity; An end cover, the end cover covers the opening; According to any one of claims 1 to 10, the connecting piece is connected to the end cover, a second channel is formed between the current collecting piece and the end cover, and the second channel is connected to the first channel.

12. The battery cell according to claim 11, characterized in that: The end cover is provided with a mounting hole; the connecting member includes a first section and a second section, the first section is inserted into the mounting hole to be connected to the end cover, and at least part of the surface of the first section is exposed to the end cover, the second section is abutted against the end cover at one end close to the first section, and is connected to the current collecting member at one end away from the first section, and the second section separates the end cover from the current collecting member to form the second channel.

13. A battery pack, characterized in that: include: Box, and At least one battery cell according to claim 11 or 12, the battery cell being accommodated in the casing.

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