A transfer sheet and an electrode transfer structure

Abstract

The present invention provides a transition piece, which includes two tab transition parts for connecting battery tabs arranged in parallel along the x direction and in the same plane, and a pole transition part arranged between the inner sides of the two tab transition parts and connected to the two tab transition parts along the y direction; a semi-enclosed boss part is provided on the first side of the pole transition part, a hollow cavity is formed inside the boss part, and a pole welding port connected to the hollow cavity is provided on the second side of the pole transition part; the boss part includes a welding platform parallel to the tab transition part but in a different plane and a transition part connecting the welding platform to the tab transition part. In the transition piece provided by the present invention, a horizontal connection structure and an angle connection structure are formed between the pole transition part and the tab transition part at the same time, and the two connection structures cooperate with each other to improve the bending resistance between the pole transition part and the tab transition part.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium batteries, and in particular relates to a switching plate and an electrode switching structure. Background Art

[0002] Due to the non-renewable nature of fossil energy and the pollution problems caused by its use, more and more fields are beginning to look for alternatives to fossil energy. For example, in recent years, new energy vehicles powered by electricity have gradually gained market share. The use of large and medium-sized electric equipment such as electric vehicles, electric bicycles and other electric vehicles and energy storage facilities has become an important technical means to solve global problems such as energy crises and environmental pollution. The development of these fields depends largely on the development of high-performance batteries. For example, in order to achieve a high endurance performance comparable to that of existing fuel vehicles, electric vehicles need to ensure that the battery capacity is large and the space occupied is small. Lithium batteries have a high energy density and high space utilization, and have a broad application prospect in the field of new energy.

[0003] The patent document with application number CN201910082660.1 discloses an adapter, which includes a flat plate and a convex bulge. The lower end of the convex bulge is arranged on the upper side of the flat plate. The convex bulge is a semi-closed convex structure. The lower end of the convex bulge is provided with an opening. The flat plate is provided with a first through hole, which is in conduction with the opening. The convex bulge has an upper end electrically connected to the battery conductive module, and the flat plate is used to electrically connect the battery pole ear. In the patent technical solution, the adapter is in the shape of a "mountain", and the two branches of the adapter located on both sides are used to connect with the pole ears, and the branch located in the middle is used to connect with the top cover. The space occupied by the three branches of the adapter is relatively large, which is not conducive to the improvement of the battery energy density, and the branch located in the middle that is connected to the top cover is easy to bend, deform, or even break after being stressed. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a transfer plate, which occupies a small area, is easy to weld with the pole ear and the cover plate, and is not prone to bending and breaking.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A transfer sheet, comprising two tab transfer parts for connecting battery tabs, arranged in parallel along the x-direction and in the same plane, and a pole transfer part arranged between the inner sides of the two tab transfer parts and connected along the y-direction to form a connection between the two tab transfer parts; a semi-enclosed boss part is provided on the first side of the pole transfer part, a hollow cavity is formed inside the boss part, and a pole welding port connected to the hollow cavity is provided on the second side of the pole transfer part; the boss part comprises a welding platform parallel to the tab transfer part but in a different plane and a transition part connecting the welding platform to the tab transfer part.

[0007] It should be noted that the x-direction and y-direction mentioned in the present invention refer to any two directions perpendicular to each other in a two-dimensional plane, and do not specifically refer to a fixed direction. Taking a two-dimensional rectangular coordinate system as an example, the positive direction of the x-axis and the negative direction of the x-axis in the coordinate system are collectively referred to as the x-direction mentioned in the present invention, and the same applies to the y-direction.

[0008] In the adapter provided by the present invention, the pole adapter is arranged between the inner sides of the two tab adapters, and the pole adapter is provided with a semi-enclosed boss, and the welding platform of the boss is connected to the tab adapter through a transition portion. In the prior art, the pole adapter and the tab adapter are usually a basically integrated planar structure. When a torsional force is applied between the two planar structures, the connection point is easily deformed, resulting in bending between the pole adapter and the tab adapter, and the transition portion described in the present invention is used to connect the welding platform and the tab adapter at different plane heights, so a connection structure perpendicular to each other or at a certain angle is formed between the transition portion and the tab adapter, and the pole connection portion and the tab connection portion In addition to forming an integrated planar structure area, an angle structure area is also included between the pole connection portion and the tab connection portion. When a torsional force is applied between the tab connection portion and the pole adapter portion, the bending resistance threshold generated by the planar structure area and the angle structure area will be greater than the integrated planar structure in the prior art, so it is not easy for the tab adapter and the pole adapter to bend. At the same time, the pole connection portion is arranged between the inner sides of the two tab connection portions, so the area occupied by the adapter does not exceed the rectangular area surrounded by the outer sides of the two tab adapter portions, which is beneficial to improving the energy density.

[0009] Furthermore, the pole transition portion is connected to the middle part of the inner side of the pole lug transition portion, and each pole lug transition portion forms two welding ends extending in opposite directions relative to the pole transition portion, and an empty area is formed between the two welding ends extending in the same direction on different pole lug transition portions.

[0010] Furthermore, the platform welding portion is rectangular, and the transition portion includes four connecting side surfaces, two of which face the y direction, and the other two connecting side surfaces face the x direction.

[0011] Furthermore, two connecting side surfaces of the transition portion facing the y direction form a transition connection with the inner side edges of the tab adapter portion.

[0012] Furthermore, the pole transition portion also includes a planar connection portion, which is in the same plane as the pole lug transition portion and whose two ends are respectively connected to the inner sides of the two pole lug transition portions, and the two connecting side surfaces of the transition portion facing the x-direction and one end away from the welding platform form a transition connection with the planar connection portion.

[0013] Furthermore, the thickness of the adapter sheet is 0.6-2.0 mm, and the protruding height of the boss portion relative to the plane where the tab adapter portion is located is 1.5-2.0 mm.

[0014] Another object of the present invention is to provide an electrode conversion structure, which includes a battery cell pole group and any one of the above-mentioned electrode conversion sheets; the battery cell pole group includes two battery cell units arranged in parallel, and the positive and negative poles of each battery cell unit are respectively connected to a pole ear; in the two battery cell units, the two pole ears connected to the positive pole are connected through an electrode conversion sheet, and the two pole ears connected to the negative pole are connected through another electrode conversion sheet; the pole ear includes a welding portion located at the end and a middle portion that connects the welding portion to the positive or negative pole of the battery cell unit, and the welding portion is attached to the pole ear conversion portion of the electrode conversion sheet to form a welded connection.

[0015] Furthermore, the pole transition portion is connected to the middle part of the inner side of the pole tab transition portion, and each pole tab transition portion forms two welding ends extending in opposite directions relative to the pole transition portion; the area where the pole tab transition portion and the pole tab form a welding connection is located at its two welding ends.

[0016] Furthermore, the motor switching structure also includes a protective sheet, and the protective sheet is arranged on the surface of the welding portion of the pole ear.

[0017] Furthermore, the electrode transfer structure also includes a cover plate assembly, which is provided with a positioning groove that matches the shape of the boss portion, the boss portion is embedded in the positioning groove to form a matching structure, and the embedded end of the boss portion is welded and fixed to the pole of the cover plate assembly.

[0018] The application of the present invention can achieve the following beneficial effects:

[0019] 1. In the adapter provided by the present invention, the pole adapter part is connected to the inner side of the pole tab adapter part, so the overall length of the adapter in the x direction does not exceed the length of the pole tab adapter part, and the overall occupied area of ​​the adapter does not exceed the rectangular area enclosed by the outer sides of the two pole tab adapter parts, which occupies less space than the adapter in the prior art.

[0020] 2. In the adapter provided by the present invention, a variety of connection structures are formed between the pole adapter part and the pole lug adapter part. For example, in some embodiments, on the one hand, a horizontal connection structure is formed between the pole adapter part and the pole lug adapter part through a planar connection part, and on the other hand, an angle connection structure is formed by connecting the side surfaces. The two connection structures cooperate with each other to improve the bending resistance between the pole adapter part and the pole lug adapter part.

[0021] 3. In some embodiments, the cover plate assembly is provided with a positioning groove, and the boss portion of the adapter plate can cooperate with the positioning groove, so that the adapter plate and the cover plate assembly cannot slide relative to each other in the x-direction or y-direction, or rotate relative to each other, thereby improving welding accuracy.

[0022] 4. In some embodiments, the two pole lug transition parts of the adapter plate each have two welding ends. When the welding ends are used as welding sites, the welding sites of the pole lug transition parts can be staggered with the welding sites of the pole post transition parts to avoid mutual influence between the pole lug welding and the pole post welding. At the same time, the adapter plate has elastic deformation space when subjected to a force perpendicular to the plane direction, thereby reducing the probability of fracture. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the structure of an adapter sheet in an embodiment;

[0024] Figure 2 for Figure 1 A schematic diagram of the front cross-sectional structure of the intermediate transfer piece;

[0025] Figure 3 It is a schematic structural diagram of an adapter sheet in another embodiment;

[0026] Figure 4 for Figure 4 A schematic diagram of the front cross-sectional structure of the intermediate transfer piece;

[0027] Figure 5 It is a schematic structural diagram of an adapter sheet in another embodiment;

[0028] Figure 6 A schematic diagram of an electrode switching structure in one embodiment;

[0029] Figure 7 is a schematic diagram of an electrode switching structure in another embodiment;

[0030] In the figure, 1-adapter, 2-cell pole group, 3-cover assembly, 11-ear adapter, 12-pole adapter, 13-vacant area, 21-cell unit, 22-ear, 23-protective sheet, 31-pole, 32-cover body, 33-cover insulating member, 111-welding end, 121-boss, 122-hollow cavity, 123-pole welding port, 124-planar connecting portion, 1311-welding platform, 1312-transition portion. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention; the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance. In addition, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" 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 it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Example

[0033] like Figure 1 and Figure 2As shown, the present invention provides a transfer sheet, the material of the transfer sheet is conductive metal, which is mainly composed of AL1060. The transfer sheet includes two long strip-shaped pole lug transfer parts 11 arranged along the x direction, the two pole lug transfer parts are arranged in the same plane, and in the middle of the inner sides of the two pole lug transfer parts close to each other, the pole column transfer part 12 connects the two pole lug transfer parts in the y direction, that is, the two pole lug transfer parts on both sides respectively form a conductive path with the middle pole column transfer part, and because the pole column transfer part connects the middle parts of the two pole lug transfer parts, each pole lug transfer part will form two welding ends 111 extending in opposite directions relative to the pole column transfer part in the x direction, and under the interval formed by the pole column transfer part, a vacant area 14 is formed between the two welding ends extending in the same direction on the two pole lug transfer parts, that is, the position of the pole column transfer part in the x direction limits the two ends of the pole lug transfer part. As a preferred embodiment, the length of the vacant area in the y direction is slightly greater than the length of the pole lug transition part in the y direction, so that the pole transition part has a larger area for subsequent welding operations, and the length of the vacant area in the x direction is 20% to 30% of the length of the pole lug transition part, that is, the length of the pole transition part in the x direction is 40% to 60% of the pole lug transition part, while ensuring the connection strength between the pole transition part and the pole lug transition part, the welding end has a certain area, which is convenient for the subsequent connection between the pole lug transition part and the pole lug. A semi-enclosed boss portion 121 is provided on the first side of the pole transition part (the side that is welded with the pole when in use), and a hollow cavity 122 is formed inside the boss portion. A pole welding port 123 connected to the hollow cavity is formed on the second side of the pole transition part. When welding the pole, the welding head performs welding operations from the pole welding port to connect the boss portion to the pole. The boss portion includes a welding platform 1311 and a transition portion 1312 that allows the welding platform to eventually form an electrical path with the pole lug transition portion. The outer surface of the welding platform is planar so as to be connected to the pole. In this embodiment, the shape of the welding platform is roughly rectangular, and the transition portion has four connecting side surfaces that are substantially perpendicular to the welding platform. Each connecting side surface corresponds to one side of the rectangle, and among the four connecting side surfaces, two connecting side surfaces face the x-direction, and two connecting side surfaces face the y-direction. The two connecting side surfaces facing the y-direction are directly connected to the inner side edges of the pole lug transition portion. In addition to the boss portion, the pole transition portion is also provided with a planar connecting portion 124. The planar connecting portion is in the shape of a long strip and is arranged on the outer side of the boss portion in the x-direction. The planar connecting portion and the pole lug transition portion are in the same plane, and its two ends in the y-direction are respectively connected to the inner sides of the two pole lug transition portions. Among the above-mentioned four connecting side surfaces, the connecting side surface facing the x-direction is connected to the planar connecting portion 124.The tab protection sheet of this embodiment can be connected to the tab from the first side through the tab adapter and connected to the pole from the second side, so that an electrical path is formed between the tab and the pole. Since it has two tab adapters, it can be connected to the two tabs and form a parallel structure with the two tabs, thereby realizing battery capacity expansion.

[0034] In another embodiment, the connecting side surface of the boss portion may be a curved structure, such as Figure 3 and Figure 4 An adapter sheet is shown, in which the four connecting side surfaces of the adapter sheet are all "S"-shaped curved surfaces, and the curved connecting side surfaces can form a more natural transition with the welding platform, the tab connecting portion and the planar connecting portion.

[0035] In another embodiment, the welding platform of the boss portion may be in a shape other than a rectangle, such as Figure 5 The welding platform of the adapter shown is circular, so the boss portion is cylindrical and the transition portion is formed by an integral arc-shaped side surface. In another embodiment, the welding platform can also be an elliptical structure, or an elliptical structure with a rectangular middle portion and semicircular ends.

[0036] like Figure 6 As shown, an embodiment of the present invention further provides a battery pole lug adapter structure, which is composed of a battery cell pole group 2 and an adapter sheet 1. The battery cell pole group includes two battery cell units 21 arranged in parallel and a pole lug 22 arranged at one end of the battery cell unit. Each battery cell unit includes a pole lug connected to the anode and a pole lug connected to the cathode. The two battery cell units are arranged closely, and the two pole lugs connected to the anode of the battery cell unit are arranged on the same side, and the two pole lugs connected to the cathode of the battery cell unit are arranged on the other side. The two pole lugs connected to the anode are connected in parallel through a adapter sheet, and the two pole lugs connected to the cathode are connected in parallel through another adapter sheet. Specifically, the adapter sheet is as follows: Figures 1 to 6As shown in any one, the two pole lug transfer parts on both sides of the adapter are each connected to a pole lug. The pole lug forms a "7"-shaped structure, wherein the transverse structure is a welding part, which is used to form a welding connection with the pole lug transfer part of the adapter, and the longitudinal structure is a middle part, which is used to connect the welding part to the battery cell unit. Before the pole lug is welded to the adapter, the welding part and the middle part are an integrated planar structure. After the welding part and the adapter are welded, the pole lug is bent to form a "7"-shaped structure. Specifically, during welding, the welding part forms a welding connection with the welding end of the pole lug transfer part, that is, two welding sites are formed between the welding part of each pole lug and the pole lug transfer part through two welding ends. Through this welding method, the welding sites of the pole lug transfer part and the pole column transfer part can be staggered to avoid mutual influence when the pole lug transfer part and the pole column transfer part are welded separately. Furthermore, in order to protect the welding portion and prevent the welding head from directly contacting the pole ear and causing damage to the pole ear structure, a protective sheet 23 is also provided at the welding portion. Furthermore, in order to prevent the pole ear from breaking during the bending process, the protective sheet 23 includes a main body made of metal material and a corner protection piece arranged on the side where the pole ear is to form a corner. The corner protection piece forms a non-sharp surface structure, so that a natural transition can be formed during the bending process of the pole ear instead of forming a sharp corner.

[0037] like Figure 7As shown, an embodiment of the present invention also provides another battery pole ear transfer structure, which is formed by connecting a battery cell pole group 2, a transfer sheet 1 and a cover plate assembly 3 in sequence, wherein the battery cell pole group is used to store electric energy, the transfer sheet is used to form an electric path between the battery cell pole group and the cover plate assembly, and the cover plate assembly is used to transmit electric energy between external devices. The battery cell pole group includes two battery cell units and a pole ear arranged at one end of the battery cell unit, each battery cell unit includes a pole ear connected to the anode and a pole ear connected to the cathode, the two battery cell units are arranged closely, and the two pole ears connected to the anode of the battery cell unit are arranged on the same side, and the two pole ears connected to the cathode of the battery cell unit are arranged on the same side, the two pole ears connected to the anode are connected in parallel through a transfer sheet, and the two pole ears connected to the cathode are connected in parallel through another transfer sheet. The cover plate assembly includes a cover plate body 32, a cover plate insulator 33 and a pole 31 that passes through the cover plate body and the cover plate insulator. The cover plate assembly is provided with a positioning groove on one side facing the adapter plate. The shape of the positioning groove is consistent with the boss portion of the adapter plate, so that the boss portion can be embedded in the positioning groove and form a matching fixation. The boss portion includes a rectangular welding platform and a transition portion including four connecting side surfaces. The welding platform of the boss portion is connected to the inner end of the pole of the cover plate assembly and connected as a whole by laser welding. The four connecting side surfaces of the boss portion are respectively abutted against the positioning groove, so that the adapter plate and the cover plate assembly cannot slide in the x-direction or y-direction, and cannot rotate relative to each other, thereby improving the welding accuracy. In addition, during the welding process, the semi-enclosed hollow cavity inside the transition portion forms a relatively independent space, and the welding slag generated during the welding process will be trapped in the hollow cavity and will not splash to other parts.

[0038] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A transfer sheet, characterized in that: It includes two tab adapters for connecting battery tabs, which are arranged in parallel along the x direction and in the same plane, and a pole adapter along the y direction, which is arranged between the inner sides of the two tab adapters and connects the two tab adapters; a semi-enclosed boss portion is provided on the first side of the pole adapter, a hollow cavity is formed inside the boss portion, and a pole welding port connected to the hollow cavity is formed on the second side of the pole adapter; the boss portion includes a welding platform parallel to the tab adapter but in a different plane and a transition portion connecting the welding platform to the tab adapter; the pole adapter is connected to the middle part of the inner side of the tab adapter, and each of the tab adapters is connected relative to the pole The column transition portion forms two welding ends extending in opposite directions, and a vacant area is formed between two welding ends extending in the same direction on different pole ear transition portions; the platform welding portion is rectangular, and the transition portion includes four connecting side surfaces, two of which face the y direction, and the other two face the x direction; the two connecting side surfaces facing the y direction are directly connected to the inner sides of the pole ear transition portion; the pole column transition portion also includes a planar connection portion, which is in the same plane as the pole ear transition portion and whose two ends in the y direction are respectively connected to the inner sides of the two pole ear transition portions, and the two connecting side surfaces of the transition portion facing the x direction, one end away from the welding platform, form a transition connection with the planar connection portion.

2. The adapter according to claim 1, characterized in that: The thickness of the adapter sheet is 0.6-2.0 mm, and the protruding height of the boss portion relative to the plane where the tab adapter portion is located is 1.5-2.0 mm.

3. An electrode switching structure, characterized in that: It comprises a battery cell electrode group and the adapter sheet as claimed in claim 1 or 2; the battery cell electrode group comprises two battery cell units arranged in parallel, and the positive electrode and the negative electrode of each battery cell unit are respectively connected to a pole ear; in the two battery cell units, the two pole ears connected to the positive electrode are connected through a adapter sheet, and the two pole ears connected to the negative electrode are connected through another adapter sheet; the pole ears comprise a welding portion located at the end and a middle portion connecting the welding portion to the positive electrode or the negative electrode of the battery cell unit, and the welding portion is attached to the pole ear adapter portion of the adapter sheet to form a welded connection.

4. The electrode switching structure according to claim 3, characterized in that: The pole transition portion is connected to the middle part of the inner side of the pole tab transition portion, and each pole tab transition portion forms two welding ends extending in opposite directions relative to the pole transition portion; the area where the pole tab transition portion and the pole tab form a welding connection is located at its two welding ends.

5. The electrode switching structure according to claim 4, characterized in that: It also includes a protection sheet, which is arranged on the surface of the welding part of the pole ear.

6. The electrode switching structure according to claim 3, characterized in that: It also includes a cover plate assembly, which is provided with a positioning groove that matches the shape of the boss portion, the boss portion is embedded in the positioning groove to form a matching structure, and the embedded end of the boss portion is welded and fixed to the pole of the cover plate assembly.

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