Switching assembly and battery

Abstract

The utility model relates to an adapter assembly and a battery. The switching assembly comprises a connecting piece, the connecting piece comprises a collecting part and a plurality of first connecting parts, and each first connecting part is used for being connected with one side, in the thickness direction, of one tab; wherein the plurality of first connecting parts are distributed along the thickness direction of the tabs and are all connected with the collecting part, and two adjacent first connecting parts can be respectively connected with two adjacent tabs in one battery cell or connected with different sides of the same tab along the thickness direction. Through the mode, when the composite current collector is adopted, the switching assembly can lead out current of the metal layers on the two sides of each tab to the outside through the first connecting part, so that the pole can be electrically connected with all the tabs only by being connected with the collecting part of the connecting piece, and the problem that when the composite current collector is adopted, the current of the metal layers on the two sides of the tabs is influenced is solved. And electric connection between all the tabs and the switching assembly is difficult to realize.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to a switching assembly and a battery. Background Art

[0002] The cell of a secondary battery is composed of a wound or stacked basic unit structure, which usually includes a separator and a pole piece. The pole piece includes a pole ear, which is usually a part of the current collector in the pole piece, and is electrically connected to the outside through the pole ear; in addition, the pole piece includes a negative pole piece and a positive pole piece; the separator separates the positive pole piece and the negative pole piece to prevent the positive and negative pole pieces from contacting and causing a short circuit.

[0003] The current collector in the pole piece is usually a metal current collector, that is, a metal foil such as aluminum foil or copper foil. In order to improve the performance of secondary batteries, a composite current collector has been developed. The composite current collector is a "sandwich" structure with metal layers such as Cu or Al on both sides and an insulating layer in the middle. The insulating layer can be a polymer material such as PET (Polyethyleneterephthalate), PP (Polypropylene) or PI (Polyimide).

[0004] However, the composite current collector increases the manufacturing difficulty compared to the existing metal current collector, especially in the welding process between the pole ear and the adapter assembly. Due to the presence of the intermediate insulating layer, the metal layers on both sides of the pole ear are electrically insulated, and it is impossible to achieve electrical connection between all the pole ears and the adapter sheet by stacking multiple pole ears and welding them together with the adapter assembly as when using a metal current collector. In other words, it is difficult to achieve electrical connection between all the pole ears and the adapter assembly. Utility Model Content

[0005] Based on this, it is necessary to provide a transition assembly and a battery to address the problem that it is difficult to achieve electrical connection between all the tabs and the transition assembly when a composite current collector is used.

[0006] In the first aspect, the present application provides an adapter assembly, which includes a connector, which includes a collecting portion and a plurality of first connecting portions, each of which is used to connect to one side of a pole ear along the thickness direction; wherein the plurality of first connecting portions are distributed along the thickness direction of the pole ear and are all connected to the collecting portion, and two adjacent first connecting portions can respectively connect to two adjacent pole ears in a battery cell or connect to different sides of the same pole ear along the thickness direction.

[0007] In one of the embodiments, the adapter assembly further includes a lead-out piece, and the lead-out piece is connected to the collecting portion.

[0008] In one embodiment, the connector also includes a second connecting portion, the first connecting portion and the second connecting portion are connected to opposite ends of the collecting portion, and two adjacent second connecting portions can respectively connect two adjacent pole ears in another battery cell or connect different sides of the same pole ear along the thickness direction.

[0009] In one embodiment, the first connecting portion is connected to the side surface of the collecting portion; or,

[0010] The first connection portion is connected to an upper surface and / or a lower surface of the collecting portion.

[0011] In one embodiment, the first connection portion is connected to a side surface of the collecting portion, and the first connection portion is flexibly connected to the collecting portion.

[0012] In one embodiment, the first connection portion is connected to the upper surface and / or lower surface of the collecting portion, and the first connection portion is welded to the collecting portion.

[0013] In a second aspect, the present application further provides a battery, comprising:

[0014] A battery cell, wherein a plurality of tabs stacked in a thickness direction are provided on the battery cell, and the tabs are formed by a composite current collector;

[0015] The adapter assembly;

[0016] Wherein, each of the first connecting portions is distributed along the stacking direction of the electrode tabs and is electrically connected to each of the electrode tabs respectively.

[0017] In one embodiment, the pole ear includes an insulating layer and a metal layer located on both sides of the insulating layer, the two opposite metal layers of two adjacent pole ears are in contact with each other, and the first connecting portion of the connecting member is used to connect to one of the two metal layers in contact with each other or to connect to both metal layers at the same time.

[0018] In one embodiment, along the stacking direction, the lengths of the plurality of pole ears are first increased in sequence to form a first step structure, and then decreased in sequence to form a second step structure, so that at least a portion of each pole ear is exposed to form a connection area; or, the plurality of pole ears include long pole ears and short pole ears, and along the stacking direction, the long pole ears and the short pole ears are alternately arranged, and the exposed portion of the long pole ears forms a connection area;

[0019] The first connecting portion is connected to the connecting area.

[0020] In one embodiment, along the stacking direction, the lengths of the plurality of pole ears are first sequentially increased to form a first step structure, and then sequentially decreased to form a second step structure, so that at least a portion of each pole ear is exposed to form a connection area, and the lengths of the plurality of first connection parts are first sequentially decreased, and then sequentially increased, and the first connection parts are connected to the connection area.

[0021] The above-mentioned adapter assembly and battery include a connector, which includes a collecting portion and multiple first connecting portions, and the first connecting portion is used to connect to the pole lug; the multiple first connecting portions are distributed along the thickness direction of the pole lug and are all connected to the collecting portion. In this way, when a composite current collector is used, the adapter assembly can lead the current of the metal layers on both sides of each pole lug to the outside through the first connecting portion, so that the pole only needs to be connected to the collecting portion of the connector to achieve electrical connection with all pole lugs. The adapter assembly provided in the present application can achieve electrical connection with each pole lug through a connector, which solves the problem that it is difficult to achieve electrical connection between all pole lugs and the adapter assembly when a composite current collector is used, and the adapter assembly provided in the present application has a simple structure. Since the first connecting portion connecting the pole lug is independently arranged, multiple first connecting portions can be welded in sequence when connected to the pole lug, which is easy to operate and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the structure of a switching component in an embodiment.

[0023] Figure 2 FIG. 4 is a schematic diagram of the structure of a battery cell in an embodiment.

[0024] Figure 3 Schematic diagram of the positional relationship between the lead-out member and the connecting member in one embodiment.

[0025] Figure 4 Schematic diagram of an embodiment in which both sides of a connector have battery cells.

[0026] Figure 5 It is a schematic diagram of the structure of a switching component in another embodiment.

[0027] Description of reference numerals:

[0028] 10. Adapter assembly; 11. Connector; 111. Collection part; 112. First connection part; 113. Second connection part; 12. Lead-out part; 13. Welding position; 20. Tab; 30. Battery cell; 31. Finishing glue; X. Distribution direction. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0030] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0032] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0033] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0035] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0036] Composite current collector is one of the mainstream trends in the subsequent development of the industry. However, the existence of the internal insulating layer of the composite current collector cannot be welded using ultrasonic welding like the traditional welding process. The traditional method is to use copper or aluminum to connect the metal layers on both sides through the roll welding process. This method has a complex manufacturing process and high production cost, so a new connection method needs to be considered.

[0037] See also Figure 1 , Figure 1 The schematic diagram of the structure of the adapter assembly 10 in one embodiment of the present application is shown. The adapter assembly 10 provided in one embodiment of the present application includes a connector 11, and the connector 11 includes a collecting portion 111 and a plurality of first connecting portions 112. The plurality of first connecting portions 112 are distributed along the thickness direction of the pole lug 20, and are all connected to the collecting portion 111. Each first connecting portion 112 is used to connect to one side of a pole lug 20 along the thickness direction. The pole lug 20 can be a positive pole lug or a negative pole lug. The connector 11 is used to electrically connect the positive electrode sheet to the outside of the battery or to electrically connect the negative electrode sheet to the outside of the battery. The number of the first connecting portions 112 can be more than two, which is specifically determined according to the number of the pole lugs 20, such as the number of the connectors 11 is equal to the number of the pole lugs 20 or greater than the number of the pole lugs 20.

[0038] The adjacent first connection parts 112 can respectively connect two adjacent tabs 20 in a battery cell 30 or connect different sides of the same tab 20 along the thickness direction. The collection part 111 refers to the collection part 111 where the current passing through the multiple connection parts 112 is collected and output or input in a centralized manner.

[0039] In a specific embodiment, Figure 1 As shown, two adjacent connecting members 11 on both sides are respectively connected to different pole lugs 20 , and two adjacent connecting members 11 in the middle are connected to opposite sides of the same pole lug 20 .

[0040] In this way, when a composite current collector is used, the adapter assembly 10 can lead the current flowing through the metal layer on each pole ear to the collecting portion 111 through the first connecting portion 112, so that the pole only needs to be connected to the collecting portion 111 of the connector 11 to achieve electrical connection with all pole ears 20. The adapter assembly 10 provided in the present application can achieve electrical connection with each pole ear 20 through the connector 11, which solves the problem that it is difficult to achieve electrical connection between all pole ears 20 and the adapter assembly when a composite current collector is used, and the adapter assembly provided in the present application has a simple structure. Since the first connecting portion 112 for connecting the pole ears is independently provided, multiple first connecting portions 112 can be welded in sequence when connected to the pole ears, which is easy to operate and has good application prospects.

[0041] In some embodiments, the first connection portion 112 may be a sheet-like structure or a strip-like structure. It is understood that the present application does not limit the shape of the first connection portion 112 as long as it can achieve electrical connection with the tab 20 .

[0042] See also Figure 3 , Figure 3 The positional relationship between the lead-out member 12 and the connector 11 in one embodiment is shown. In some embodiments, the adapter assembly 10 further includes a lead-out member 12 , which is connected to the collecting portion 111 of the connector 11 , thereby achieving electrical connection with all the tabs 20 .

[0043] The lead-out member 12 is connected to the collecting portion 111 of the connector 11, so that the current of the tabs 20 can be easily led out, so that the external structure and the lead-out member 12 can be connected to each tab 20 to achieve electrical connection. Optionally, the lead-out member 12 can be electrically connected to a pole provided on the battery, so that the tab 20 is electrically connected to the outside through the pole, and the pole is a conventional design in the art and will not be described in detail here.

[0044] See also Figure 4 , Figure 4 A schematic diagram is shown in which there are battery cells on both sides of the connector 11 in an embodiment. The connector 11 also includes a second connecting portion 113, and the first connecting portion 112 and the second connecting portion 113 are connected to opposite ends of the collecting portion 111, that is, the collecting portion 111 is located in the middle of the connector 11, and two adjacent second connecting portions 113 can respectively connect two adjacent tabs 20 in another battery cell 30 or connect different sides of the same tab 20 along the thickness direction. The second connecting portion 113 can adopt the same structure and connection method as the first connecting portion 112, which will not be described in detail.

[0045] In this embodiment, both sides of the connector 11 can be connected to the tabs 20 , so that one adapter assembly can be connected to two battery cells at the same time, thus simplifying the battery structure and reducing costs.

[0046] In some embodiments, the first connection portion 112 is connected to the side surface of the collecting portion 111. Figure 3 Further, the first connection portion 112 is flexibly connected to the collecting portion 111, so that when the first connection portion 112 is connected to the pole lug 20, the angle between the first connection portion 112 and the collecting portion 111 in the thickness direction can be adjusted, so that pole lugs 20 of different sizes can be adapted and connected.

[0047] In some other embodiments, the first connecting portion 112 is connected to the upper surface and / or the lower surface of the collecting portion 111. Figure 5 , Figure 5 It is shown that a portion of the first connection portion 112 is connected to the upper surface of the collecting portion 111, and a portion is connected to the lower surface of the collecting portion 111. Of course, in other embodiments, the first connection portion 112 can be entirely disposed on the upper surface of the collecting portion 111 or entirely disposed on the lower surface of the collecting portion 111. In this embodiment, similar to the above, a second connection portion 113 can also be disposed on the collecting portion 111, which will not be described in detail here. Furthermore, the first connection portion 112 is welded to the collecting portion 111 to form a welding position 13, so that each first connection portion 112 can be welded to the pole lug 20 respectively, and then the first connection portions 112 located on the same side of the collecting portion 111 are gathered and welded to the upper surface or lower surface of the collecting portion 111 in a stacked manner, thereby achieving electrical connection between the collecting portion 111 and the pole lug 20.

[0048] The present application also provides a battery, which includes a battery cell 30 and an adapter assembly 10 in any of the above embodiments. A plurality of pole tabs 20 stacked in the thickness direction are provided on the battery cell 30. Among them, each first connection 112 portion is distributed along the stacking direction of the pole tab 20, and is electrically connected to each pole tab 20 respectively. The stacking direction of the pole tab 20 is consistent with the distribution direction X of the connector 11, and the electrical connection between the first connection portion 112 and the pole tab 20 can be a direct connection or an indirect connection. Optionally, the pole piece includes a composite current collector and an active material layer formed on the composite current collector, and the pole tab 20 is a partial composite current collector on which the active material is not deposited.

[0049] The tab 20 of the battery cell 30 can be a positive tab or a negative tab. When both the positive tab and the negative tab use a composite current collector, two sets of adapter components 10 are required to connect the positive tab and the negative tab respectively.

[0050] For the composite current collector layer, the tab 20 includes an insulating layer and metal layers located on both sides of the insulating layer, the two opposite metal layers of two adjacent tabs 20 are in contact with each other, and the first connecting portion 112 of the connector 11 is used to connect to one of the two metal layers in contact with each other or to connect to both metal layers at the same time. Further, for the connector 11 having the second connecting portion 113, the second connecting portion 113 is also connected to one of the two metal layers in contact with each other of the tab in another battery cell or to both metal layers at the same time.

[0051] In one embodiment, along the stacking direction, the lengths of the plurality of tabs 20 are first increased sequentially to form a first step structure, and then sequentially decreased to form a second step structure, so that at least a portion of the adjacent tabs 20 are exposed to form a connection area, and the first connection portion 112 is connected to the connection area. In this way, the first step structure and the second step structure formed cause the adjacent tabs 20 to be misaligned, and the side edges of the tabs 20 are exposed to form a connection area, and the connector 11 can be connected to the connection area, thereby being electrically connected to the tabs 20.

[0052] In other embodiments, the plurality of tabs 20 include long tabs and short tabs (not shown), and the long tabs and the short tabs are arranged alternately along the stacking direction, and the exposed portion of the long tab forms a connection area, and the first connection portion 112 is connected to the connection area. The length of the long tab is greater than that of the short tab.

[0053] Specifically, Figure 2 As shown, Figure 2 A schematic diagram of the structure of a battery cell 30 in an embodiment is shown, wherein the battery cell 30 is formed by winding a pole piece and a diaphragm, and the outermost end of the winding is bonded and fixed by a finishing glue 31. A plurality of pole tabs 20 form a step structure, the length of the pole tab 20 located in the middle position is greater than the length of the pole tabs 20 located at the two side positions, and the length of the pole tabs 20 decreases successively from the middle to the outside. In this way, the length of the middle pole tab 20 is the longest, and the longer pole tab 20 among the adjacent pole tabs 20 exposes part of the metal layer, which facilitates the connection between the metal layer and the first connecting portion 112. In other embodiments, the battery cell 30 is formed by stacking pole pieces and diaphragms to form a laminated structure, and the formation method of the battery cell is not limited in the present application.

[0054] In order to connect the adapter assembly 10 to each tab 20 and match the tab 20 structure of the battery, see Figure 1In some embodiments, along the distribution direction X of the first connection parts 112 (i.e., the thickness direction of the tab), the lengths of the plurality of first connection parts 112 first decrease in sequence and then increase in sequence. In this way, the length of the first connection part 112 located in the middle is less than the length of the first connection parts 112 located on both sides, which is exactly opposite to the length distribution of the battery tab 20. In this way, the first connection part 112 located in the middle of the adapter assembly 10 is matched and connected with the longest tab 20 located in the middle, and the longer first connection parts 112 located on both sides of the adapter assembly 10 are matched and connected with the shorter tabs 20 located on both sides, so that the structure of the adapter assembly 10 matches the structure of the tab 20 of the battery.

[0055] The present application also provides an electrical device, which includes the battery provided in the present application. The battery can be used as a power source for the electrical device, and can also be used as an energy storage unit for the electrical device. The electrical device may include mobile devices, electric vehicles, electric trains, ships and satellites, energy storage systems, etc., but are not limited thereto. Among them, the mobile device may be, for example, a mobile phone, a laptop computer, etc.; the electric vehicle may be, for example, a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, an electric golf cart, an electric truck, etc., but are not limited thereto. The technical features of the above embodiments may be arbitrarily combined. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the transfer scope of the present application. Therefore, the transfer scope of the patent application shall be subject to the attached claims.

Claims

1. A switching assembly, characterized in that: The adapter assembly includes a connector, which includes a collecting portion and a plurality of first connecting portions, each of which is used to connect to one side of a pole ear along the thickness direction; wherein the plurality of first connecting portions are distributed along the thickness direction of the pole ear and are all connected to the collecting portion, and two adjacent first connecting portions can respectively connect to two adjacent pole ears in a battery cell or connect to different sides of the same pole ear along the thickness direction.

2. The adapter assembly according to claim 1, characterized in that: The adapter assembly also includes a lead-out piece, and the lead-out piece is connected to the collecting portion.

3. The adapter assembly according to claim 1, characterized in that: The connector also includes a second connecting portion, the first connecting portion and the second connecting portion are connected to opposite ends of the collecting portion, and two adjacent second connecting portions can respectively connect two adjacent tabs in another battery cell or connect different sides of the same tab along the thickness direction.

4. The adapter assembly according to claim 1, characterized in that: The first connection portion is connected to a side surface of the collecting portion; or, The first connection portion is connected to an upper surface and / or a lower surface of the collecting portion.

5. The adapter assembly according to claim 4, characterized in that: The first connection portion is connected to a side surface of the collecting portion, and the first connection portion is flexibly connected to the collecting portion.

6. The adapter assembly according to claim 4, characterized in that: The first connection portion is connected to the upper surface and / or the lower surface of the collecting portion, and the first connection portion is connected to the collecting portion by welding.

7. A battery, characterized in that: The battery comprises: A battery cell, wherein a plurality of tabs stacked in a thickness direction are provided on the battery cell, and the tabs are formed by a composite current collector; The adapter assembly according to any one of claims 1 to 6; Wherein, each of the first connecting portions is distributed along the stacking direction of the electrode tabs and is electrically connected to each of the electrode tabs respectively.

8. The battery according to claim 7, characterized in that The pole lug includes an insulating layer and metal layers located on both sides of the insulating layer. The two opposite metal layers of two adjacent pole lugs are in contact with each other. The first connecting portion of the connecting member is used to connect to one of the two metal layers in contact with each other or to connect to both metal layers at the same time.

9. The battery according to claim 8, characterized in that Along the stacking direction, the lengths of the plurality of pole ears are first increased in sequence to form a first step structure, and then decreased in sequence to form a second step structure, so that at least a portion of each pole ear is exposed to form a connection area; or, the plurality of pole ears include long pole ears and short pole ears, and along the stacking direction, the long pole ears and the short pole ears are alternately arranged, and the exposed portion of the long pole ears forms a connection area; The first connecting portion is connected to the connecting area.

10. The battery according to claim 9, characterized in that Along the stacking direction, the lengths of the plurality of pole ears first increase in sequence to form a first step structure, and then decrease in sequence to form a second step structure, so that at least a portion of each pole ear is exposed to form a connection area, and the lengths of the plurality of first connection parts first decrease in sequence, and then increase in sequence, and the first connection parts are connected to the connection area.

Images