Photovoltaic module

Abstract

The utility model relates to a photovoltaic module, which is beneficial to prolonging the service life and improving the reliability of the photovoltaic module. The photovoltaic module comprises a plurality of battery strings, wherein each battery string comprises a plurality of battery pieces arranged at intervals along a first direction and at least one welding strip which extends along the first direction and is electrically connected with the plurality of battery pieces; the bus bar structure is configured to enable two adjacent battery strings to form a series connection structure or a parallel connection structure, the bus bar structure comprises a first bus bar group arranged on one side of the battery strings in the first direction, the first bus bar group comprises at least two first bus bars extending in the second direction, and the first bus bars extend in the second direction. The first bus bar is electrically connected with the welding strip, the first direction is perpendicular to the thickness direction of the photovoltaic module, and the second direction intersects with the first direction.

Description

Technical Field

[0001] The present application relates to the photovoltaic field, and in particular to a photovoltaic module. Background Art

[0002] As the energy shortage situation continues to intensify, the development and utilization of renewable energy is imminent. Among the many renewable energy sources, solar energy has outstanding advantages such as no danger of depletion, safety and reliability, no noise, no pollution emissions, and its application is not restricted by the distribution area of ​​resources.

[0003] Photovoltaic power generation is a technology that uses the photovoltaic effect of semiconductor interfaces to directly convert light energy into electrical energy. Photovoltaic modules are the core units of solar power generation and are packaged from a number of cells.

[0004] In the current preparation process of photovoltaic modules, generally, multiple battery cells are first connected in series through welding ribbons to form a battery string, and then the welding ribbons of the battery string are electrically connected to the bus bar, and the bus bar is used to realize the series or parallel connection of multiple battery strings to form a photovoltaic cell array.

[0005] In the related art, the reliability of the electrical connection between the welding strip and the bus bar is low, and the connection is prone to breakage, causing the photovoltaic module to fail, which is not conducive to improving the life and reliability of the photovoltaic module. Utility Model Content

[0006] Based on the above problems, the present application provides a photovoltaic module to improve the life and reliability of the photovoltaic module.

[0007] A photovoltaic module includes a plurality of battery strings and a busbar structure. The battery string includes a plurality of battery cells arranged at intervals along a first direction and at least one welding strip extending along the first direction and electrically connected to the plurality of battery cells. The busbar structure is configured to form a series structure or a parallel structure for two adjacent battery strings, the busbar structure includes a first busbar group arranged on one side of the battery string in the first direction, the first busbar group includes at least two first busbars extending in a second direction, the first busbars are electrically connected to the welding strips, the first direction is perpendicular to the thickness direction of the photovoltaic module, and the second direction intersects with the first direction.

[0008] In some embodiments, the number of the first bus bars is two.

[0009] In some embodiments, the bus bar structure further includes a second bus bar group disposed on the other side of the battery string in the first direction, the second bus bar group includes at least two second bus bars extending along the second direction, and the second bus bars are electrically connected to the welding strips.

[0010] In some embodiments, the number of the second bus bars is two.

[0011] In some embodiments, the first bus bar and the second bus bar are connected to the welding ribbon by at least one of welding, conductive adhesive connection, and insulating adhesive bonding.

[0012] In some embodiments, at least one notch is disposed on the first bus bar and the second bus bar, and the notch extends along the first direction. In the thickness direction of the photovoltaic module, the notch is disposed opposite to the welding strip.

[0013] In some embodiments, at least a portion of the welding ribbon is located in the notch, and the welding ribbon is electrically connected to the first bus bar and the second bus bar by welding.

[0014] In some embodiments, the busbar structure further includes a conductive adhesive, at least a portion of which is located in the notch, and the welding ribbon is electrically connected to the first busbar and the second busbar through the conductive adhesive.

[0015] In some embodiments, the busbar structure further includes insulating glue, at least a portion of the welding strip is located in the notch and in contact with an inner wall of the notch, and the welding strip is bonded to the first busbar and the second busbar through the insulating glue.

[0016] In some embodiments, the cross-sectional shape of the notch is one of a rectangle, a semicircle, an arc, and a trapezoid.

[0017] In the present application, the busbar structure includes a first busbar group, the first busbar group includes at least two first busbars, and at least one welding strip on the battery string needs to be electrically connected to at least two first busbars. In this way, even if the electrical connection between a first busbar and the welding strip fails, the electrical connection between the welding strip and the first busbar group can still be ensured through the connection between other first busbars and the welding strip, which is conducive to improving the reliability of the electrical connection between the welding strip and the first busbar, and further conducive to improving the reliability and life of the photovoltaic module. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] FIG1 is a schematic structural diagram of a series-connected photovoltaic cell array of a photovoltaic module according to an embodiment of the present application;

[0020] FIG2 is a schematic structural diagram of a parallel photovoltaic cell array of a photovoltaic module according to an embodiment of the present application;

[0021] FIG3 is a schematic structural diagram of a battery string connected to a busbar structure in an embodiment of the present application;

[0022] FIG4 is a schematic cross-sectional view of a section AA shown in FIG3 ;

[0023] FIG5 is a schematic cross-sectional view of a section BB shown in FIG3 ;

[0024] Figure 6 is another cross-sectional schematic diagram of the AA point shown in FIG3 ;

[0025] Figure 7 It is another cross-sectional schematic diagram of the BB position shown in FIG3 ;

[0026] Figure 8 It is another cross-sectional schematic diagram of the AA point shown in FIG3;

[0027] Fig. 9 It is another cross-sectional schematic diagram of the BB portion shown in FIG. 3 . DETAILED DESCRIPTION

[0028] 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.

[0029] In the description of the present application, 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 application 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 application.

[0030] 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 this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] In this application, 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 this application can be understood according to specific circumstances.

[0032] In the present application, 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”, and “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”, and “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.

[0033] 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.

[0034] The embodiment of the present application proposes a photovoltaic module 10. As shown in Figures 1 and 2, the photovoltaic module 10 includes a plurality of battery strings 100 and a busbar structure 200. The battery string 100 includes a plurality of battery cells 110 arranged at intervals along a first direction X and at least one welding strip 120 extending along the first direction X and electrically connected to the plurality of battery cells 110. The busbar structure 200 is configured to form a series structure or a parallel structure for two adjacent battery strings 100. The busbar structure 200 includes a first busbar group 210 disposed on one side of the battery string 100 in the first direction X, the first busbar group 210 includes at least two first busbars 211 extending in a second direction Y, the first busbar 211 is electrically connected to the welding strip 120, the first direction X is perpendicular to the thickness direction Z of the photovoltaic module 10, and the second direction Y intersects with the first direction X.

[0035] The photovoltaic module 10 of the present application includes a plurality of battery strings 100 and a bus bar structure 200. In the plurality of battery strings 100, two adjacent battery strings 100 form a series structure or a parallel structure through the bus bar structure 200, thereby forming a photovoltaic battery array. The specific structures of the parallel photovoltaic battery array 11 and the series photovoltaic battery array 12 are described below.

[0036] FIG1 is a schematic diagram of a structure of a series photovoltaic cell array 12 of an embodiment of the present application. As shown in FIG1 , the series photovoltaic cell array 12 includes six battery strings 100 connected in series, and the positive poles (+) and negative poles (-) of two adjacent battery strings 100 are connected in series through a busbar structure 200. Of course, in practice, the number of battery strings 100 connected in series in the series photovoltaic cell array 12 can be more or less.

[0037] FIG2 is a schematic diagram of the structure of a parallel photovoltaic cell array 11 of an embodiment of the present application. As shown in FIG2, the parallel photovoltaic cell array 11 includes a first part 11a and a second part 11b arranged in parallel, that is, the same electrode of two adjacent battery strings 100 at the junction of the first part 11a and the second part 11b, such as the negative electrode (-), is connected in parallel through a busbar structure 200. Among them, the first part 11a includes three battery strings 100, and two adjacent battery strings 100 are connected in series through the busbar structure 200. Of course, in practice, the number of battery strings 100 connected in series in the first part 11a can be more or less. Similarly, the second part 11b includes two battery strings 100 connected in series. In practice, the number of battery strings 100 connected in series in the second part 11b can be more or less.

[0038] As can be seen from the above, the connection method of the busbar structure 200 and the battery string 100 determines the specific structure of the photovoltaic cell array. As shown in Figure 3, it is a structural schematic diagram of the connection between one of the battery strings 100 and the busbar structure 200 of the present application. The battery string 100 includes a plurality of battery cells 110 and at least one welding strip 120. The plurality of battery cells 110 are connected in series through the welding strip 120, so that the current of the plurality of battery cells 110 is converged on the welding strip 120. At least one welding strip 120 means that the number of welding strips 120 can be 1, 2, or more than 2. When the number of welding strips 120 is 2 or more, each welding strip 120 extends along the first direction X, and adjacent welding strips 120 are arranged at intervals. In this way, it is conducive to improving the current collection effect. It should be noted that in the accompanying drawings, 3 battery cells 110 in the battery string 100 are exemplarily drawn, but it is not used as a limitation on the number of battery cells 110 in the battery string 100 of the present application. In each battery string 100 , the number of battery cells 110 can be flexibly set according to actual needs.

[0039] The busbar structure 200 includes a first busbar group 210, which is located on one side of the battery string 100 in the first direction X. The first busbar group 210 is used to collect the current on the welding strip 120, and is also used to connect with the adjacent battery string 100. The first busbar group 210 includes at least two first busbars 211 extending along the second direction Y. Among them, at least two first busbars 211 extending along the second direction Y mean that the number of first busbars 211 can be 2, or more than 2, and the two adjacent first busbars 211 can be arranged at intervals or in contact with each other. When two adjacent first busbars 211 are arranged at intervals, they can be parallel to each other or non-parallel, and the present application does not make specific restrictions. Preferably, in order to improve the convenience of connecting the first busbar group 210 with the welding strip 120, and to reduce the area occupied by the first busbar group 210, the two adjacent first busbars 211 are arranged in parallel and at intervals.

[0040] In the present application, the busbar structure 200 includes a first busbar group 210, and the first busbar group 210 includes at least two first busbars 211. At least one welding ribbon 120 on the battery string 100 needs to be electrically connected to at least two first busbars 211. In this way, even if the electrical connection between a first busbar 211 and the welding ribbon 120 fails, the electrical connection between the welding ribbon 120 and the first busbar group 210 can still be ensured through the connection between other first busbars 211 and the welding ribbon 120, which is conducive to improving the reliability of the electrical connection between the welding ribbon 120 and the first busbar 211, and further to improving the reliability and life of the photovoltaic module 10.

[0041] In a specific embodiment, there are two first busbars 211. In this way, firstly, the reliability of the electrical connection between the welding ribbon 120 and the first busbar group 210 is improved, thereby improving the reliability and life of the photovoltaic module 10. Secondly, the area occupied by the first busbar group 210 is not too large, thereby also improving the power generation efficiency of the photovoltaic module 10.

[0042] In a specific embodiment, as shown in FIG3 , there are three welding strips 120 in each battery string 100. In this way, on the one hand, it is beneficial to improve the current collection efficiency of the battery string 100, and on the other hand, the increase in the number of welding strips 120 further increases the connection points between the first bus bar group 210 and the welding strips 120, which is beneficial to further improve the reliability of the electrical connection between the welding strips 120 and the first bus bar 211, and further improve the reliability and life of the photovoltaic module 10.

[0043] In some embodiments, as shown in Figures 1 to 3, the bus bar structure 200 also includes a second bus bar group 220 arranged on the other side of the battery string 100 in the first direction X, and the second bus bar group 220 includes at least two second bus bars 221 extending along the second direction Y, and the second bus bar 221 is electrically connected to the welding strip 120.

[0044] In this embodiment, the busbar structure 200 also includes a second busbar group 220. That is, the second busbar group 220 and the first busbar group 210 are respectively located at the head and tail ends of the battery string 100, and both are used to collect the current of the welding strip 120 and connect other battery strings 100. Further, the second busbar group 220 includes at least two second busbars 221 extending along the second direction Y, and the second busbars 221 are electrically connected to the welding strip 120. In this way, even if the electrical connection between a second busbar 221 and the welding strip 120 fails, the electrical connection between the welding strip 120 and the second busbar group 220 can still be guaranteed through the connection between other second busbars 221 and the welding strip 120, which is conducive to improving the reliability of the electrical connection between the welding strip 120 and the second busbar group 220, and further conducive to improving the reliability and life of the photovoltaic module 10.

[0045] In a specific embodiment, the number of the second busbars 221 is two. In this way, firstly, the reliability of the electrical connection between the welding strip 120 and the second busbar group 220 is improved, thereby improving the reliability and life of the photovoltaic module 10. Secondly, the area occupied by the second busbar group 220 is not too large, thereby also improving the power generation efficiency of the photovoltaic module 10.

[0046] In some embodiments, the first bus bar 211 and the second bus bar 221 are connected to the welding strip 120 by at least one of welding, conductive adhesive connection, and insulating adhesive bonding. This embodiment proposes a variety of ways to connect the first bus bar 211 and the second bus bar 221 to the welding strip 120. Among them, the conductive adhesive refers to an adhesive with electrical conductivity. That is, conductive particles are doped in the adhesive. The conductive adhesive includes isotropic conductive adhesive and anisotropic conductive adhesive, which is not limited in this application. Insulating adhesive bonding refers to connecting the welding strip 120 to the first bus bar 211 or the second bus bar 221 using insulating adhesive. When the insulating adhesive bonding method is used, in order to ensure the reliability of the electrical connection between the welding strip 120 and the first bus bar 211 and the second bus bar 221, it is necessary to first contact the welding strip 120 with the first bus bar 211 or the second bus bar 221, and then use insulating adhesive bonding. The above-mentioned methods can all achieve electrical connection between the welding ribbon 120 and the first bus bar 211 and between the welding ribbon 120 and the second bus bar 221 , thereby facilitating the preparation convenience of the photovoltaic module 10 .

[0047] In some embodiments, as shown in Figures 4 and 5, and referring to Figure 3, at least one notch 230 is provided on the first bus bar 211 and the second bus bar 221, and the notch 230 extends along the first direction X. In the thickness direction Z of the photovoltaic module 10, the notch 230 is arranged opposite to the welding strip 120.

[0048] In this embodiment, at least one notch 230 is provided on the first bus bar 211 and the second bus bar 221. The notch 230 extends along the first direction X, that is, the extension direction of the notch 230 is the same as the extension direction of the welding strip 120, so that the welding strip 120 can be electrically connected to the first bus bar 211 and the second bus bar 221 in an embedded manner. At least one notch 230 means that the number of notches 230 in the first bus bar 211 or the second bus bar 221 can be 1, or 2 or more. Specifically, in the thickness direction Z of the photovoltaic module 10, the notch 230 is arranged relative to the welding strip 120. That is, the notch 230 and the welding strip 120 are in a one-to-one correspondence. In Figures 4 and 5, an exemplary drawing is drawn in which a welding strip 120 is embedded in the notch 230. In practice, the number of notches 230 is the same as the number of welding strips 120, and the number of notches 230 can be set accordingly according to the number of welding strips 120 in the battery string 100.

[0049] Optionally, in order to improve the convenience of embedding and connecting the welding ribbon 120 with the first bus bar 211 and the second bus bar 221, in the first bus bar group 210, the notch 230 on the first bus bar 211 farthest from the battery string 100 may penetrate the first bus bar 211 along the first direction X, or not penetrate the first bus bar 211; the notches 230 on the other first bus bars 211 penetrate the first bus bar 211 along the first direction X. In the second bus bar group 220, the notch 230 on the second bus bar 221 farthest from the battery string 100 may penetrate the second bus bar 221 along the first direction X, or not penetrate the second bus bar 221; the notches 230 on the other second bus bars 221 penetrate the second bus bar 221 along the first direction X.

[0050] In some embodiments, the cross-sectional shape of the notch 230 is one of a rectangle, a semicircle, an arc, and a trapezoid. The notch 230 of the above shape is easy to manufacture, thereby facilitating the convenience of embedding connection. Optionally, the cross-sectional shape of the notch 230 matches the cross-sectional shape of the welding strip 120, thereby facilitating the convenience of embedding connection further.

[0051] In some embodiments, as shown in FIGS. 4 and 5 , at least a portion of the welding ribbon 120 is located in the notch 230, and the welding ribbon 120 is electrically connected to the first bus bar 211 and the second bus bar 221 by welding. In this embodiment, since the notch 230 is provided on the first bus bar 211 and the second bus bar 221. When the welding ribbon 120 is electrically connected to the first bus bar 211 and the second bus bar 221 by welding, at least a portion of the welding ribbon 120 can be placed in the notch 230, and the welding is completed by embedding, which is conducive to further improving the reliability of the electrical connection between the welding ribbon 120 and the first bus bar 211 and the second bus bar 221.

[0052] In some embodiments, Figure 6 and Figure 7 As shown, the busbar structure 200 further includes a conductive adhesive 240, at least part of which is located in the notch 230, and the soldering strip 120 is electrically connected to the first busbar 211 and the second busbar 221 through the conductive adhesive 240. In this embodiment, the soldering strip 120 is electrically connected to the first busbar 211 and the second busbar 221 by connecting with the conductive adhesive 240. At this time, at least part of the conductive adhesive 240 can be filled in the notch 230, and then the soldering strip 120 is electrically connected to the first busbar 211 and the second busbar 221. In this way, the reliability of the conductive adhesive connection is improved.

[0053] In some embodiments, Figure 8 and Fig. 9As shown, the busbar structure 200 further includes an insulating adhesive 250, at least a portion of the welding strip 120 is located in the notch 230 and contacts the inner wall of the notch 230, and the welding strip 120 is bonded to the first busbar 211 and the second busbar 221 through the insulating adhesive 250. In this embodiment, the welding strip 120 is electrically connected to the first busbar 211 and the second busbar 221 by bonding with the insulating adhesive 250. At this time, at least a portion of the welding strip 120 is first placed in the notch 230 and contacts the inner wall of the notch 230 to ensure the conductive performance of the welding strip 120 and the first busbar 211 and the second busbar 221, and then the insulating adhesive 250 is used to bond the welding strip 120 to the first busbar 211 and the welding strip 120 to the second busbar 221. In this way, it is beneficial to improve the reliability of the insulating adhesive bonding while ensuring the conductive performance.

[0054] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0055] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed 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 protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A photovoltaic module, characterized in that: include: A plurality of battery strings, each battery string comprising a plurality of battery cells arranged at intervals along a first direction and at least one welding strip extending along the first direction and electrically connected to the plurality of battery cells; as well as A bus bar structure, wherein the bus bar structure is configured to enable two adjacent battery strings to form a series structure or a parallel structure, and the bus bar structure includes a first bus bar group arranged on one side of the battery string in the first direction, the first bus bar group includes at least two first bus bars extending along the second direction, the first bus bar is electrically connected to the welding strip, the first direction is perpendicular to the thickness direction of the photovoltaic module, and the second direction intersects with the first direction.

2. The photovoltaic module according to claim 1, characterized in that: The number of the first bus bars is two.

3. The photovoltaic module according to claim 1, characterized in that: The busbar structure further includes a second busbar group disposed on the other side of the battery string in the first direction, the second busbar group includes at least two second busbars extending along the second direction, and the second busbars are electrically connected to the welding strips.

4. The photovoltaic module according to claim 3, characterized in that: The number of the second bus bars is two.

5. The photovoltaic module according to claim 3, characterized in that: The first bus bar and the second bus bar are connected to the welding strip by at least one of welding, conductive adhesive connection, and insulating adhesive bonding.

6. The photovoltaic module according to claim 3, characterized in that: At least one notch is provided on the first bus bar and the second bus bar. The notch extends along the first direction. In the thickness direction of the photovoltaic module, the notch is arranged opposite to the welding strip.

7. The photovoltaic module according to claim 6, characterized in that: At least a portion of the welding strip is located in the notch, and the welding strip is electrically connected to the first bus bar and the second bus bar by welding.

8. The photovoltaic module according to claim 6, characterized in that: The busbar structure further includes a conductive adhesive, at least a portion of which is located in the notch, and the welding strip is electrically connected to the first busbar and the second busbar through the conductive adhesive.

9. The photovoltaic module according to claim 6, characterized in that: The busbar structure further includes insulating glue, at least a portion of the welding strip is located in the notch and contacts the inner wall of the notch, and the welding strip is bonded to the first busbar and the second busbar through the insulating glue.

10. The photovoltaic module according to claim 6, characterized in that: The cross-sectional shape of the notch is one of a rectangle, a semicircle, an arc, and a trapezoid.

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