Solder strip for ECA welding, battery assembly and battery system

Abstract

The utility model discloses a welding strip for ECA welding, a battery assembly and a battery system, and belongs to the technical field of batteries. The welding strip comprises dispensing parts and supporting parts which are alternately arranged in the length direction, on the dispensing side of the welding strip, every two adjacent supporting parts and the dispensing part between the two adjacent supporting parts are in a concave shape, and in the width direction of the welding strip, the width of the dispensing parts is larger than that of the supporting parts. According to the welding strip for ECA welding, the supporting part can play a supporting role, the concave glue dispensing part can play a glue adding role to prevent glue from being completely extruded out in the extrusion process, the width of the glue dispensing part is large, and the welding reliability is guaranteed; and the width of the supporting part is small, and the shading area is reduced, so that the welded battery piece can receive more light rays, and the efficiency of the battery piece is improved.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and in particular relates to an ECA welding ribbon, a battery assembly and a battery system. Background Art

[0002] Solar cells are usually connected by interconnection, where the interconnection forms can be shingles, 4BB / 5BB / SMBB / 0BB welding or BC welding. For cells that are not resistant to high temperatures (such as perovskite cells), traditional wire welding is not applicable. At present, such cells that are not resistant to high temperatures are usually interconnected by ECA (conductive adhesive) welding, but the efficiency of the cells after welding needs to be improved. Utility Model Content

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes an ECA welding ribbon, a battery assembly and a battery system, which ensures the reliability of welding and improves the efficiency of the battery cell.

[0004] In the first aspect, the present application provides a soldering strip for ECA welding, which includes a glue dispensing portion and a supporting portion alternately arranged along the length direction. On the glue dispensing side of the soldering strip, the glue dispensing portion between two adjacent supporting portions is concave, and in the width direction of the soldering strip, the width of the glue dispensing portion is greater than the width of the supporting portion.

[0005] According to the ECA welding soldering strip of the present application, the supporting portion can play a supporting role, and the concave glue dispensing portion can play a glue-replenishing role to prevent the glue from being completely squeezed out during the extrusion process. The width of the glue dispensing portion is relatively wide, thereby ensuring the reliability of welding; and since the width of the supporting portion is relatively small, the shading area is reduced, so that the battery cell after welding can receive more light, thereby improving the efficiency of the battery cell.

[0006] According to one embodiment of the present application, in the length direction, the cross-sectional shape of the middle portion of the support portion on the first cross-section is circular or elliptical, and the first cross-section is a cross-sectional shape perpendicular to the length direction.

[0007] According to one embodiment of the present application, the outer contour line of the connection between adjacent glue dispensing parts and supporting parts is in the shape of a continuous curve.

[0008] According to an embodiment of the present application, on the glue dispensing side of the soldering tape, the surfaces of the glue dispensing portion and the supporting portion are both continuous curved surfaces.

[0009] According to one embodiment of the present application, in the length direction, the length range of the support portion is 0.1 mm-100 mm.

[0010] According to one embodiment of the present application, the glue dispensing side includes a first side and a second side opposite to the welding strip, and the morphology of the first side is symmetrical to the morphology of the second side.

[0011] In a second aspect, the present application provides a battery assembly, including a battery cell and a welding ribbon for ECA welding according to the aforementioned method, wherein the battery cell has a main grid, and the welding ribbon for ECA welding is welded to the main grid through a conductive material.

[0012] According to the battery assembly of the present application, the reliability of welding between the battery cell and the ECA welding ribbon is high, and the efficiency of the battery cell is relatively high.

[0013] According to one embodiment of the present application, the main grid has welding areas and non-welding areas alternately arranged along the extension direction, the welding areas are arranged corresponding to the glue dispensing part of the ECA welding ribbon, and the non-welding areas are arranged corresponding to the supporting part of the ECA welding ribbon, and the area of ​​the non-welding areas is smaller than the area of ​​the welding areas.

[0014] According to one embodiment of the present application, the non-welding area is hollowed out.

[0015] In a third aspect, the present application provides a battery system comprising at least one battery assembly according to the foregoing.

[0016] According to the battery system of the present application, the performance of the battery system is better due to the high reliability and efficiency of the battery assembly welding.

[0017] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0019] Figure 1 It is a schematic diagram of the structure of the welding strip provided in the embodiment of the present application;

[0020] Figure 2 It is a schematic structural diagram of a support portion of a welding strip provided in an embodiment of the present application;

[0021] Figure 3 It is a structural schematic diagram of the glue dispensing part of the soldering tape provided in the embodiment of the present application;

[0022] Figure 4 is a schematic diagram of the structure of a battery cell provided in an embodiment of the present application;

[0023] Figure 5 This is one of the structural schematic diagrams of the main grid provided in the embodiment of the present application;

[0024] Figure 6 This is the second structural diagram of the main grid provided in the embodiment of the present application:

[0025] Figure 7 This is one of the schematic diagrams of grid line arrangement of a battery cell provided in an embodiment of the present application;

[0026] Figure 8 This is the second schematic diagram of the grid line arrangement of the battery cell provided in the embodiment of the present application;

[0027] Fig. 9 This is the third schematic diagram of the grid line arrangement of the battery cell provided in the embodiment of the present application;

[0028] Fig.10 This is the fourth schematic diagram of the grid line arrangement of the battery cell provided in the embodiment of the present application.

[0029] Reference numerals:

[0030] Solder ribbon 10 , glue dispensing portion 11 , support portion 12 , battery cell 20 , main grid 21 , fine grid 22 , welding area 23 , non-welding area 24 . DETAILED DESCRIPTION

[0031] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0032] The following description relates to elements or components that are "connected" or "coupled" together. As used herein, "connection" may refer to an element / component being mechanically coupled to (or directly connected to) another element / component, and is not necessarily direct. Similarly, "coupling" may refer to an element / component being directly or indirectly coupled to (or directly or indirectly connected to) another element / component, and is not necessarily mechanical. However, it should be understood that although in one embodiment, two elements are described below as "connected", similar elements may be "coupled" in alternative embodiments, and vice versa. Therefore, although the schematic diagram shown here describes an exemplary arrangement of elements, additional intermediate elements, devices, parts or components may still exist in a practical embodiment.

[0033] Reference Figure 1 , Figure 2 and Figure 3 , Figure 1 The structure of a welding strip for ECA welding is shown. Figure 2 A structure of a support portion is shown. Figure 3 An embodiment of the present application provides a soldering ribbon for ECA soldering.

[0034] In this embodiment, the solder strip 10 for ECA welding includes a glue dispensing portion 11 and a support portion 12 alternately arranged along the length direction X. On the glue dispensing side of the solder strip 10, the glue dispensing portion 11 between two adjacent support portions 12 is concave, and in the width direction Y of the solder strip 10, the width of the glue dispensing portion 11 is greater than the width of the support portion 12.

[0035] ECA welding refers to connecting the welding ribbon 10 to the welding object using ECA (conductive material). The ECA material can be dotted on the welding ribbon 10 and then bonded to the welding object. Among them, the welding object includes batteries, etc., and the ECA material can be a conductive adhesive, solder, solder paste, conductive tape, and any other material used to electrically and mechanically connect electrode PV battery segments.

[0036] The material of the welding strip 10 can be a conductive material, for example, a metal material such as copper or silver, or other types of conductive materials.

[0037] In the length direction of the soldering ribbon 10, the glue dispensing part 11 and the supporting part 12 can be arranged in contact, that is, there is no other part between the glue dispensing part 11 and the supporting part 12. Generally speaking, the number of glue dispensing parts 11 and the supporting part 12 can be set according to demand, and the more the number of glue dispensing parts 11, the higher the welding reliability. The number of glue dispensing parts 11 and the supporting part 12 can be set according to demand, and this embodiment does not limit this.

[0038] As an example, Figure 1 As shown, the downward portion of the solder ribbon 10 can be the glue dispensing side, and the glue dispensing portion 11 between two adjacent support portions 12 is concave to form a notch. The ECA material can be dispensed at the glue dispensing portion 11. During welding, even if the solder ribbon 10 and the welding object are squeezed, the ECA material can be retained in the notch and will not be completely separated under the squeeze, thereby ensuring the reliability of welding.

[0039] In some embodiments, the soldering ribbon 10 is soldered to the battery. When the soldering ribbon 10 is subjected to ECA soldering, the plane formed by the length direction X and the width direction Y is parallel to the soldering surface of the battery. The soldering surface of the battery is usually the light-receiving surface, so the soldering ribbon 10 will affect the amount of light received by the battery.

[0040] In this embodiment, in the width direction Y, the width of the glue dispensing portion 11 can be set to meet the ECA welding requirements, so that the width of the support portion 12 can be reduced, thereby reducing shading.

[0041] According to the ECA welding soldering tape 10 of the present application, the support portion 12 can play a supporting role, and the concave glue dispensing portion 11 can play a glue-replenishing role to prevent the glue from being completely squeezed out during the extrusion process. The width of the glue dispensing portion 11 is relatively wide, thereby ensuring the reliability of welding; and since the width of the support portion 12 is relatively small, the shading area is reduced, so that the battery cell after welding can receive more light, thereby improving the efficiency of the battery cell.

[0042] As an example, the glue dispensing portion 11 in the soldering ribbon 10 can be obtained by flattening. The initial shape of the soldering ribbon 10 is a columnar body with the same cross section in each section in the length direction X, and the cross section of each section can be circular (i.e., cylindrical), elliptical or polygonal, etc. By flattening the initial soldering ribbon 10 according to a certain gap, the ECA soldering ribbon 10 provided in the present application can be obtained.

[0043] In this example, the flattened portion of the initial solder strip 10 forms the glue dispensing portion 11, and the remaining portion is the support portion 12. Generally, in the length direction X, the middle portion of the support portion 12 can retain the cross-sectional shape of the initial solder strip 10.

[0044] Continue to refer to Figure 2 and Figure 3 In some embodiments, the cross-sectional shape of each section of the initial welding strip 10 in the length direction X can be circular or elliptical. That is, the cross-sectional shape of the middle part of the support portion 12 of the ECA welding welding strip 10 provided in the present application in the first cross-sectional shape is circular or elliptical, and the first cross-sectional shape is a cross-sectional shape perpendicular to the length direction X.

[0045] The first cross section is also parallel to the width direction Y. Usually, when performing the flattening process, an extrusion structure is required to extrude the solder strip 10. The portion where the extrusion structure contacts the solder strip 10 can be used as a glue dispensing portion. During the extrusion process, the portion of the support portion 12 close to the extrusion structure will also deform with the deformation of the glue dispensing portion 11, so the cross-sectional shape of the portion of the support portion 12 close to the extrusion structure will also deviate from the initial cross-sectional shape of the solder strip 10.

[0046] In this embodiment, by controlling the degree of extrusion, the middle part of the support part 12 of the solder strip 10 is not deformed, and the initial cross-sectional shape of the solder strip 10 is retained. Thus, the more the glue dispensing part 11 is recessed, the deeper the notch is for storing glue, and the better the glue storage effect is.

[0047] In some embodiments, the outer contour line of the connection between adjacent glue dispensing parts 11 and supporting parts 12 is in the shape of a continuous curve.

[0048] It is understandable that, since the glue dispensing portion 11 is formed by extrusion, the portion of the support portion 12 of the solder strip 10 close to the extrusion structure will also deform with the deformation of the glue dispensing portion, so that the outer contour line of the connection between the adjacent glue dispensing portion 11 and the support portion 12 is a continuous curve. Extrusion molding is simpler than cutting and other processes.

[0049] In some embodiments, on the glue dispensing side of the soldering ribbon, the surfaces of the glue dispensing portion 11 and the supporting portion 12 are both continuous curved surfaces.

[0050] It is understandable that the surfaces of the glue dispensing part 11 and the supporting part 12 are continuous curved surfaces, and the sidewalls of the glue storage slot are curved. And due to the use of extrusion molding, it is not easy to form sharp angles in the slot, thereby improving the glue refilling effect, ensuring that the ECA material in the slot is filled, and improving the reliability of welding.

[0051] Of course, in other embodiments, the bottom surface of the glue dispensing portion 11 may also be a plane, that is, the contact surface between the extrusion structure and the initial soldering ribbon 10 is flat, so that the glue dispensing portion 11 after being flattened forms a plane.

[0052] In some embodiments, the length of the support portion 12 is in the range of 0.1 mm to 100 mm in the length direction X. For example, the length of the support portion may be 0.1 mm, 50 mm, or 100 mm.

[0053] In some embodiments, the difference in vertex height between the support portion 12 and the glue dispensing portion 11 ranges from 0.05 mm to 2 mm. For example, the difference in vertex height between the support portion 12 and the glue dispensing portion 11 may be 0.05 mm, 0.1 mm, or 0.5 mm.

[0054] When the total length of the soldering ribbon 10 is constant, the length of the support portion 12 represents the number of the glue dispensing portions 11 . By setting the length of the support portion 12 , the number of the glue dispensing portions 11 can be arranged.

[0055] In some embodiments, the dispensing side includes a first side and a second side opposite to the solder strip 10 , and the morphology of the first side is symmetrical to the morphology of the second side.

[0056] Continue to refer to Figure 1 The upper and lower sides of the welding strip 10 can be used to connect the battery. This can increase the form of ECA welding and facilitate the connection configuration of the battery.

[0057] In this embodiment, the initial welding strip 10 may be a body of revolution, and the extrusion structure may form a first side and a second side with symmetrical shapes by extruding two opposite sides of the body of revolution.

[0058] Reference Figure 4 , Figure 4The structure of the first battery cell is shown. An embodiment of the present application also provides a battery assembly.

[0059] In this embodiment, the battery assembly includes a battery cell 20 and the aforementioned ECA welding ribbon 10 , the battery cell 20 has a main grid 21 , and the ECA welding ribbon 10 is welded to the main grid 21 through a conductive material.

[0060] It is understood that the battery cell is usually provided with a main grid 21, a fine grid 22 (also called a secondary grid) and a side grid (not shown in the figure), the fine grid 22 and the side grid are mainly responsible for collecting the current generated by the battery cell, and the main grid 21 is responsible for collecting the current collected by the fine grid 22 and the side grid and transmitting it to the outside of the battery. The fine grid 22 and the side grid are usually made simultaneously by screen printing process.

[0061] The welding strip 10 can be welded to the main grid 21 by ECA welding, and the main grid 21 and the welding strip 10 are connected by the ECA material. The current collected by the main grid 21 is transmitted to the welding strip 10 through the ECA material, and then transmitted to the outside through the welding strip 10. The specific structure and principle of the welding strip 10 can refer to the aforementioned embodiments, and this embodiment will not be repeated here.

[0062] According to the battery assembly of the present application, the reliability of welding between the battery cell and the ECA welding ribbon 10 is high, and the efficiency of the battery cell is relatively high.

[0063] Reference Figure 5 , Figure 5 In some embodiments, the main grid 21 has welding areas 23 and non-welding areas 24 arranged alternately along the extension direction, the welding areas 23 are arranged corresponding to the glue dispensing part 11 of the ECA welding ribbon 10, and the non-welding areas 24 are arranged corresponding to the supporting part 12 of the ECA welding ribbon 10, and the area of ​​the non-welding areas 24 is smaller than the area of ​​the welding areas 23.

[0064] After ECA welding, the welding ribbon 10 overlaps with the main grid 21. In the overlapping direction, the projection of the glue dispensing portion 11 of the welding ribbon 10 on the main grid 21 is located in the welding area 23, and the projection of the supporting portion 12 of the welding ribbon 10 on the main grid 21 is located in the non-welding area 24. The ECA material is mainly located between the glue dispensing portion 11 of the welding ribbon 10 and the welding area 23 of the main grid 21.

[0065] It is understandable that since the main grid 21 is also located on the light-receiving surface of the cell 20, the main grid 21 will also affect the amount of light received by the cell 20. In the present application, the area of ​​the welding area 23 of the main grid 21 can be set according to the requirements of ECA welding, and the non-welding area 24 of the main grid 21 can be reduced in area to reduce light blocking, thereby improving the efficiency of the cell 20.

[0066] Reference Figure 6 , Figure 6 The structure of the second main grid is shown. In some embodiments, the non-welding area 24 of the main grid 21 is hollowed out.

[0067] In this embodiment, the non-welding area 24 of the main grid 21 is a hollow structure, that is, the non-welding area 24 of the main grid 21 directly exposes the structure of the battery cell 20 below, thereby better improving the amount of light received by the battery cell 20 and improving the efficiency of the battery cell 20.

[0068] Reference Figure 7 and Figure 8 , Figure 7 The first grid line arrangement of the cell is shown. Figure 8 A second gridline arrangement of a cell is shown.

[0069] As an example, the non-welding area 24 of the main grid 21 is not a hollow structure, but the area of ​​the non-welding area 24 is smaller than the area of ​​the welding area 23. Figure 7 As shown, the intersection of the main grid 21 and the auxiliary grid 22 may be located below the non-welding area 24. Figure 8 As shown, the intersection of the grid 21 and the auxiliary grid 22 may be located below the welding area 23 .

[0070] Reference Fig. 9 and Fig.10 , Fig. 9 The third grid line arrangement of the cell is shown. Fig.10 A fourth gridline arrangement for a cell is shown.

[0071] As an example, the non-welding area 24 of the main grid 21 is a hollow structure. Fig. 9 As shown, the intersection of the main grid 21 and the auxiliary grid 22 may be located below the non-welding area 24. Fig.10 As shown, the intersection of the grid 21 and the auxiliary grid 22 may be located below the welding area 23 .

[0072] An embodiment of the present application further provides a battery system, the battery system comprising at least one battery assembly according to the above. The specific structure of the battery assembly can refer to the above embodiments, and this implementation will not be repeated here.

[0073] According to the battery system of the present application, the performance of the battery system is better due to the high reliability and efficiency of the battery assembly welding.

[0074] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0075] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to 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 application.

[0076] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0077] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A welding strip for ECA welding, characterized in that: The welding strip includes a glue dispensing portion and a supporting portion alternately arranged along the length direction. On the glue dispensing side of the welding strip, the glue dispensing portion between two adjacent supporting portions is concave, and in the width direction of the welding strip, the width of the glue dispensing portion is greater than the width of the supporting portion.

2. The ECA welding ribbon according to claim 1, characterized in that: In the length direction, a cross-sectional shape of a middle portion of the support portion on a first cross section is circular or elliptical, and the first cross section is a cross section perpendicular to the length direction.

3. The ECA welding ribbon according to claim 2, characterized in that: The outer contour line of the connection between the adjacent glue dispensing parts and the supporting parts is in the shape of a continuous curve.

4. The ECA welding ribbon according to claim 3, characterized in that: On the glue dispensing side of the soldering tape, surfaces of the glue dispensing portion and the supporting portion are both continuous curved surfaces.

5. The ECA welding strip according to any one of claims 1 to 4, characterized in that: In the length direction, the length of the support portion ranges from 0.1 mm to 100 mm.

6. The ECA welding strip according to any one of claims 1 to 4, characterized in that: The dispensing side includes a first side and a second side opposite to the welding strip, and the morphology of the first side is symmetrical to the morphology of the second side.

7. A battery assembly, characterized in that: It comprises a battery cell and an ECA welding ribbon according to any one of claims 1 to 6, wherein the battery cell has a main grid, and the ECA welding ribbon is welded to the main grid through a conductive material.

8. The battery assembly according to claim 7, characterized in that: The main grid has welding areas and non-welding areas alternately arranged along the extension direction, the welding areas are arranged corresponding to the glue dispensing parts of the ECA welding strip, the non-welding areas are arranged corresponding to the supporting parts of the ECA welding strip, and the area of ​​the non-welding areas is smaller than that of the welding areas.

9. The battery assembly according to claim 8, characterized in that: The non-welding area is hollow.

10. A battery system, characterized in that: Comprising at least one battery assembly according to any one of claims 7-9.

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