Battery string and photovoltaic module

Abstract

The invention discloses a battery string and a photovoltaic module, and belongs to the technical field of photovoltaic modules. The battery string comprises a battery piece which is provided with a plurality of fine grids which extend along a first direction and are arranged at intervals along a second direction; the plurality of connecting lines extend along the second direction and are arranged at intervals along the first direction, each connecting line is connected to the surface of the battery piece through a plurality of glue points which are arranged at intervals, and the second direction is perpendicular to the first direction; wherein in the direction perpendicular to the plane where the battery piece is located, the glue points are arc-shaped protrusions, the height of the arc-shaped protrusions is smaller than or equal to 200 microns, and in the first direction and the second direction, the length of the arc-shaped protrusions is larger than or equal to 1 mm and smaller than or equal to 2 mm.

Description

Technical Field

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

[0002] The battery string is the core component of the photovoltaic module, and the battery string can convert solar energy into electrical energy. Generally, the battery string includes a plurality of cells arranged at intervals, and the surface of the cell is provided with a plurality of fine grids extending along the first direction and arranged at intervals along the second direction, and the current generated by the cell is collected by the plurality of fine grids. The surface of the cell is also provided with a plurality of welding strips extending along the second direction and arranged at intervals along the first direction, and the welding strips are bonded to the surface of the cell through glue points to be electrically connected to the plurality of fine grids, so that the current collected by the plurality of fine grids is collected by the welding strips.

[0003] However, during the processing of the battery string, if the glue point is too small, the reliability of the connection between the soldering ribbon and the battery cell cannot be guaranteed. If the glue point is too large, the soldering ribbon at the glue point will be far away from the surface of the battery cell, making it impossible for the soldering ribbon to connect with the multiple fine grids on both sides of the glue point, and the soldering ribbon cannot collect the current collected by the multiple fine grids on both sides of the glue point, thus affecting the photoelectric conversion efficiency of the battery string. Summary of the invention

[0004] The present application provides a battery string and a photovoltaic module to solve or at least partially solve the problem in the prior art that during the processing of the battery string, if the glue point is too small, the reliability of the connection between the welding ribbon and the battery cell cannot be guaranteed. If the glue point is too large, the welding ribbon at the connection with the glue point will be far away from the surface of the battery cell, making it impossible for the welding ribbon to connect with the multiple fine grids on both sides of the glue point, and the welding ribbon cannot collect the current collected by the multiple fine grids on both sides of the glue point, thereby affecting the photoelectric conversion efficiency of the battery string.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, the present application discloses a battery string, comprising: a battery cell, on which are provided a plurality of fine grids extending along a first direction and arranged at intervals along a second direction; a plurality of connecting lines, the plurality of connecting lines extending along the second direction and arranged at intervals along the first direction, each of the connecting lines being connected to the surface of the battery cell through a plurality of glue points arranged at intervals, the second direction being perpendicular to the first direction; wherein, along a direction perpendicular to the plane where the battery cell is located, the glue points are arc-shaped protrusions, the height of the arc-shaped protrusions is less than or equal to 200 μm, and along the first direction and the second direction, the length of the arc-shaped protrusions is greater than or equal to 1 mm and less than or equal to 2 mm.

[0007] Optionally, along a direction perpendicular to the plane where the battery cell is located, each of the connecting lines is at least partially embedded in a plurality of the glue points spaced apart along the second direction.

[0008] Optionally, along a direction perpendicular to the plane where the battery cell is located, a depth at which the connecting wire is embedded in the glue spot accounts for 40% to 100% of a height of the glue spot.

[0009] Optionally, a cross-section of the connecting line along the second direction has a wavy structure.

[0010] Optionally, along the second direction, the connection line connected to the glue point forms an arched section, and a distance between a side of the arched section close to the battery cell and a surface of the battery cell is less than or equal to 200 um.

[0011] Optionally, along the second direction, the arched segment spans over two adjacent fine grids.

[0012] Optionally, along the second direction, the connection line between two adjacent arched segments is a horizontal segment, the horizontal segment is connected to the surface of the battery cell, and the horizontal segment is electrically connected to at least one of the fine grids.

[0013] Optionally, along a direction perpendicular to the plane where the battery cell is located, the connecting line has a first projection on the battery cell, and the length of the first projection is L1; along the second direction, the sum of the lengths of the horizontal segments is L2, wherein 0.7L1≤L2≤0.9L1.

[0014] Optionally, along the second direction, the glue spot is at least partially disposed between two adjacent fine grids; along a direction perpendicular to the plane where the battery cell is located, there is a gap between the connecting line and two of the fine grids closest to the glue spot along the second direction.

[0015] Optionally, along the second direction, there is a first gap between two adjacent fine grids, and the glue dot is arranged in the first gap.

[0016] Optionally, the connecting wire comprises a connecting wire substrate and a metal layer attached to a surface of the connecting wire substrate, wherein the metal layer on a side close to the battery cell is electrically connected to the plurality of fine grids.

[0017] Optionally, the battery cell further comprises: a TCO layer, wherein the metal layer on a side of the horizontal section of the connecting line close to the battery cell abuts against the TCO layer.

[0018] Optionally, along a direction perpendicular to the plane where the battery cell is located, the fine grid is at least partially embedded in the metal layer on a side of the horizontal section of the connecting line close to the battery cell.

[0019] Optionally, the melting point of the metal layer is less than 165 degrees.

[0020] Optionally, the metal layer is one of a tin-lead-bismuth layer, a tin-bismuth-silver layer or a tin-indium layer.

[0021] Optionally, the projection of the arc-shaped protrusion in the direction of the plane where the battery cell is located is a circle, and the diameter of the circle is greater than or equal to 1 mm and less than or equal to 2 mm.

[0022] Optionally, the dimensions of the battery cell include: (182±2)mm*(96±1)mm, (192±2)mm*(91±1)mm, (182±2)mm*(91±1)mm, (182±2)mm*(105±1)mm.

[0023] In a second aspect, the present application discloses a photovoltaic module, comprising a cover plate, a first adhesive layer, a plurality of battery strings as described in the first aspect, a second adhesive layer, and a back plate which are arranged in sequence, wherein the plurality of battery strings are arranged at intervals.

[0024] Optionally, the first adhesive layer and / or the second adhesive layer is a multi-layer composite adhesive layer.

[0025] Optionally, the multi-layer composite adhesive layer is a double-layer structure, including an EVA layer and a POE layer stacked in sequence.

[0026] Optionally, the multi-layer composite adhesive layer is a three-layer structure, including an EVA layer, a POE layer and an EVA layer stacked in sequence.

[0027] Optionally, the EVA layer directly contacts the battery string.

[0028] The present application provides a battery string and a photovoltaic module, the battery string comprising: a battery cell, the battery cell being provided with a plurality of fine grids extending in a first direction and arranged at intervals in a second direction; a plurality of connecting wires, the plurality of connecting wires extending in the second direction and arranged at intervals in the first direction, each of the connecting wires being connected to the surface of the battery cell by a plurality of glue points arranged at intervals, the second direction being perpendicular to the first direction; wherein, along the direction perpendicular to the plane where the battery cell is located, the glue point is an arc-shaped protrusion, the height of the arc-shaped protrusion is less than or equal to 200μm, and along the first direction and the second direction, the length of the arc-shaped protrusion is greater than or equal to 1mm and less than or equal to 2mm. The battery string provided in the embodiment of the present application connects the connecting wire to the surface of the battery cell by a plurality of glue points arranged at intervals, the glue point is an arc-shaped protrusion, the height of the arc-shaped protrusion is less than or equal to 200μm, and along the first direction and the second direction, the length of the arc-shaped protrusion is greater than or equal to 1mm and less than or equal to 2mm. During the processing of the battery string, the glue point can connect the connecting wire to the surface of the battery cell more firmly, so that the distance between the connecting wire connected to the glue point and the surface of the battery cell is moderate. The connecting wire can be connected to more fine grids to collect more current collected by the fine grids, thereby improving the photoelectric conversion efficiency of the battery string. The connecting wire connected to the glue point will not be far away from the surface of the battery cell, making it impossible for the connecting wire to connect to the multiple fine grids on both sides of the glue point, and the connecting wire will not be unable to collect the current collected by the multiple fine grids on both sides of the glue point. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The structure of the battery string in the embodiment of the present application is shown in FIG. Figure 1 ;

[0030] Figure 2 A cross-sectional view of the battery string along the extending direction of the connecting line in an embodiment of the present application;

[0031] Figure 3 A cross-sectional view showing the glue point described in the embodiment of the present application;

[0032] Figure 4 A cross-sectional view showing the embodiment of the present application after the connecting line is embedded in the glue point along the extending direction perpendicular to the connecting line;

[0033] Figure 5 A partial cross-sectional view of the photovoltaic module at a glue point along an extension direction perpendicular to the connection line in an embodiment of the present application;

[0034] Figure 6 A partial cross-sectional view of the photovoltaic module at a glue point along the extending direction of the connecting line in an embodiment of the present application;

[0035] Figure 7 A partial cross-sectional view of the photovoltaic module at a non-glue point along an extension direction perpendicular to the connection line in an embodiment of the present application;

[0036] Figure 8 A partial cross-sectional view of the photovoltaic module at a non-glue point along the extending direction of the connecting line in the embodiment of the present application;

[0037] Reference numerals:

[0038] 10: Cell; 11: TCO layer;

[0039] 20: fine grid;

[0040] 30: connecting line; 31: arched section; 32: horizontal section; 33: connecting line substrate; 34: metal layer;

[0041] 40: glue point;

[0042] 50: cover plate;

[0043] 60: first adhesive layer; 61: EVA layer; 62: POE layer;

[0044] A: first direction; B: second direction. DETAILED DESCRIPTION

[0045] 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 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 fixed scope of the present invention.

[0046] It should be understood that the references to "one embodiment" or "an embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present invention. Therefore, the references to "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0047] Reference Figure 1 , showing the structure of the battery string described in the embodiment of the present application Figure 1 ;reference Figure 2 , showing a cross-sectional view of the battery string along the extending direction of the connecting line in an embodiment of the present application; referring to Figure 3 , showing a cross-sectional view of the glue point described in the embodiment of the present application; referring to Figure 4, shows a cross-sectional view of the connecting line embedded in the glue point along a direction perpendicular to the extension direction of the connecting line in the embodiment of the present application; refer to Figure 5 , shows a partial cross-sectional view of the photovoltaic module at the glue point along the extending direction perpendicular to the connecting line in the embodiment of the present application; Figure 6 , shows a partial cross-sectional view of the photovoltaic module at the glue point along the extension direction of the connecting line in the embodiment of the present application; Figure 7 , shows a partial cross-sectional view of the photovoltaic module at a non-glue point along the extending direction perpendicular to the connecting line in the embodiment of the present application, referring to Figure 8 , shows a partial cross-sectional view of the photovoltaic module at a non-glue point along the extension direction of the connecting line in an embodiment of the present application.

[0048] like Figures 1 to 8 As shown, an embodiment of the present application provides a battery string, which includes: a battery cell 10, on which a plurality of fine grids 20 extending along a first direction A and arranged at intervals along a second direction B are arranged; a plurality of connecting wires 30, which extend along the second direction B and are arranged at intervals along the first direction A, each connecting wire 30 is connected to the surface of the battery cell 10 through a plurality of glue points 40 arranged at intervals, and the second direction B is perpendicular to the first direction A; wherein, along a direction perpendicular to the plane where the battery cell 10 is located, the glue point 40 is an arc-shaped protrusion, the height of the arc-shaped protrusion is less than or equal to 200 μm, and along the first direction A and the second direction B, the length of the arc-shaped protrusion is greater than or equal to 1 mm and less than or equal to 2 mm.

[0049] like Figure 1 As shown, the battery string provided in the embodiment of the present application includes a battery cell 10, which is the core component of the photovoltaic module and can convert solar energy into electrical energy. The battery cell 10 is provided with a plurality of fine grids 20 extending along a first direction A and arranged at intervals along a second direction B. The current generated by the battery cell 10 is collected by the plurality of fine grids 20.

[0050] Specifically, during the processing of the battery string, the metal paste can be printed on the surface of the battery cell 10 by screen printing to form a plurality of fine grids 20 arranged at intervals on the surface of the battery cell 10. The current generated by the battery cell 10 is collected by the plurality of fine grids 20. The fine grids 20 are conductive.

[0051] like Figure 1 As shown, the battery string provided in the embodiment of the present application further includes a plurality of connecting wires 30, each of which extends along the second direction B and is arranged at intervals along the first direction A. Each connecting wire 30 is connected to the surface of the battery cell 10 through a plurality of glue points 40 arranged at intervals. The second direction B is perpendicular to the first direction A.

[0052] Specifically, during the processing of the battery string, after printing a plurality of fine grids 20 on the surface of the battery cell 10, a plurality of glue dot columns extending along the second direction B and arranged at intervals along the first direction A can be printed on the surface of the battery cell 10 by screen printing, and a plurality of glue dots 40 are arranged at intervals in each glue dot column. A connecting wire 30 is bonded to the surface of the battery cell 10 through each glue dot column. Each connecting wire 30 is electrically connected to the plurality of fine grids 20, so that the current collected by the plurality of fine grids 20 is collected through each connecting wire 30.

[0053] It should be noted that the connection line 30 in the embodiment of the present application has a conductive property. Exemplarily, the connection line 30 can be a welding strip, a welding rod, and the like.

[0054] In the direction perpendicular to the plane where the battery cell 10 is located, the glue spot 40 is an arc-shaped protrusion, and the height of the arc-shaped protrusion is less than or equal to 200 μm. In the first direction A and the second direction B, the length of the arc-shaped protrusion is greater than or equal to 1 mm and less than or equal to 2 mm.

[0055] It should be noted that when the glue is printed on the surface of the battery cell 10 by screen printing to form the glue dots 40, the glue has a certain fluidity, so the shape of the glue dots 40 is irregular. In the embodiment of the present application, there are no excessive restrictions on the specific shape of the glue dots 40, and any shape of the glue dots 40 belongs to the protection scope of the present application.

[0056] In the embodiment of the present application, the height of the glue spot 40 is set to be less than or equal to 200 μm along the direction perpendicular to the plane where the battery cell 10 is located, and the length of the arc-shaped protrusion along the first direction A and the second direction B is set to be greater than or equal to 1 mm and less than or equal to 2 mm.

[0057] For example, along the direction perpendicular to the plane where the battery cell 10 is located, the height of the glue spot 40 can be set to 100 μm, 120 μm, 150 μm, 170 μm, 190 μm, 200 μm, etc. Along the first direction A and the second direction B, the length of the arc-shaped protrusion can be set to 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2 mm, etc.

[0058] The battery string provided in the embodiment of the present application connects the connecting wire 30 to the surface of the battery cell 10 through a plurality of glue dots 40 arranged at intervals. The glue dots 40 are arc-shaped protrusions, the height of which is less than or equal to 200 μm, and the length of which along the first direction A and the second direction B is greater than or equal to 1 mm and less than or equal to 2 mm. During the processing of the battery string, the glue dots 40 can connect the connecting wire 30 to the surface of the battery cell 10 more stably, so that the distance between the connecting wire 30 at the connection with the glue dots 40 and the surface of the battery cell 10 is moderate. The connecting wire 30 can be connected to more fine grids 20 to collect more current collected by the fine grids 20, thereby improving the photoelectric conversion efficiency of the battery string. The connecting wire 30 at the connection with the glue dots 40 will not be far from the surface of the battery cell 10, so that the connecting wire 30 cannot be connected to the multiple fine grids 20 on both sides of the glue dots 40, and the connecting wire 30 cannot collect the current collected by the multiple fine grids 20 on both sides of the glue dots 40.

[0059] As an optional implementation, Figure 2 and Figure 4 As shown, along a direction perpendicular to the plane where the battery cell 10 is located, each connection line 30 is at least partially embedded in a plurality of glue dots 40 arranged at intervals along the second direction B.

[0060] like Figure 2 and Figure 4 As shown, each connecting wire 30 is partially embedded in a plurality of glue spots 40 spaced apart along a second direction B in a direction perpendicular to the plane where the battery cell 10 is located, so that the connecting wire 30 is more firmly connected to the surface of the battery cell 10 through the plurality of glue spots 40 spaced apart along the second direction B.

[0061] As an optional implementation, Figure 2 and Figure 4 As shown, along the direction perpendicular to the plane where the battery cell 10 is located, the depth of the connecting wire 30 embedded in the glue spot 40 accounts for 40% to 100% of the height of the glue spot 40.

[0062] like Figure 2 and Figure 4 As shown, along the direction perpendicular to the plane where the battery cell 10 is located, the depth of the connecting wire 30 embedded in the glue point 40 is set to account for 40% to 100% of the height of the glue point 40, so that the connection between the connecting wire 30 and the glue point 4 is more reliable.

[0063] Specifically, along a direction perpendicular to the plane of the battery cell 10 , the depth of the connecting wire 30 embedded in the glue spot 40 can be set to 40%, 50%, 60%, 70%, 80%, 90%, 100%, etc. of the height of the glue spot 40 .

[0064] As an optional implementation, Figure 2As shown, the cross section of the connecting line 30 along the second direction B is a wavy structure.

[0065] like Figure 2 As shown, the cross section of the connecting line 30 along the second direction B is a wavy structure. Specifically, the wavy structure includes an arched section 31 and a horizontal section 32. The connecting line 30 at the connection with the glue point 40 is an arched section 31, the connecting line 30 between two adjacent arched sections 31 is a horizontal section 32, and along the second direction B, both ends of the connecting line 30 are horizontal sections 32.

[0066] That is, along the second direction B, each connecting line 30 includes a plurality of arched segments 31 and a plurality of horizontal segments 32 , the arched segments 31 and the horizontal segments 32 are arranged one by one at intervals, and the plurality of arched segments 31 and the plurality of horizontal segments 32 are connected to form the connecting line 30 .

[0067] As an optional implementation, Figure 2 As shown, along the second direction B, the connection line 30 connected to the glue point 40 forms an arched section 31, and the distance between the arched section 31 and the surface of the battery cell 10 on the side close to the battery cell 10 is less than or equal to 200 um.

[0068] like Figure 2 As shown, in the embodiment of the present application, the distance between the side of the arched section 31 close to the cell 10 and the side of the cell 10 close to the connecting wire 30 is set to be less than or equal to 200μm. In order to make the distance between the arched section 31 and the surface of the cell 10 moderate, the connecting wire 30 can be connected to more fine grids 20 to collect more current collected by the fine grids 20, thereby improving the photoelectric conversion efficiency of the battery string. Furthermore, the distance between the arched section 31 and the surface of the cell 10 is moderate, which can also avoid defects such as cell 10 fragmentation due to the arched section 31 being too high during the lamination process of the photovoltaic module.

[0069] For example, the distance between the side of the arched section 31 close to the battery cell 10 and the surface of the battery cell 10 close to the connecting line 30 can be set to 180 μm, 160 μm, 140 μm, 120 μm, 100 μm, 80 μm, etc. In this regard, the embodiment of the present application does not impose too many restrictions, and in actual use, technicians can set it as needed.

[0070] As an optional implementation, Figure 2 As shown, along the second direction B, the arched segment 31 spans over two adjacent fine grids 20 .

[0071] During the processing of the battery string, the glue point 40 is usually set between two adjacent fine grids 20. Figure 2As shown, in the embodiment of the present application, along the second direction B, the arched section 31 spans over two adjacent fine grids 20. That is, along the second direction B, the length of the arched section 31 is equivalent to the distance between two adjacent fine grids 20.

[0072] Therefore, in the embodiment of the present application, only the fine grids 20 corresponding to the arched section 31 are not connected to the connecting wire 30, while the fine grids 20 corresponding to the horizontal section 32 are all connected to the connecting wire 30. The connecting wire 30 can be connected to more fine grids 20 to improve the photoelectric conversion efficiency of the photovoltaic module.

[0073] As an optional implementation, Figure 2 As shown, along the second direction B, the connection line 30 between two adjacent arched segments 31 is a horizontal segment 32 , the horizontal segment 32 is connected to the surface of the battery cell 10 , and the horizontal segment 32 is electrically connected to at least one fine grid 20 .

[0074] like Figure 2 As shown, along the second direction B, the horizontal segment 32 is connected to the surface of the battery cell 10 , and the horizontal segment 32 is electrically connected to at least one fine grid 20 , so that the current collected by at least one fine grid 20 is collected through the horizontal segment 32 .

[0075] As an optional implementation, Figure 1 and Figure 2 As shown, along a direction perpendicular to the plane where the battery cell 10 is located, the connecting line 30 has a first projection on the battery cell 10, and the length of the first projection is L1; along the second direction B, the sum of the lengths of the horizontal segments 32 is L2, wherein 0.7L1≤L2≤0.9L1.

[0076] like Figure 1 As shown, along the direction perpendicular to the plane where the cell 10 is located, the connecting wire 30 has a first projection on the cell 10, and the length of the first projection is set to L1. Along the second direction B, the sum of the lengths of the horizontal segments 32 of the connecting wire 30 is set to L2. In this embodiment, L2 is set to be greater than or equal to 0.7L1, and L2 is less than or equal to 0.9L1. In this way, along the second direction B, the length of the horizontal segment 32 of the connecting wire 30 is long enough, and the connecting wire 30 can be connected to more fine grids 20 to collect more currents collected by the fine grids 20, thereby improving the photoelectric conversion efficiency of the battery string.

[0077] For example, L2 can be set to be equal to 0.7L1, or L2 can be set to be equal to 0.8L1, or L2 can be set to be equal to 0.9L1. Of course, the above are only individual examples of the embodiments of the present application and are not intended to be limiting of the present application. In actual production, technicians can set the length of the horizontal segment 32 as needed.

[0078] As an optional implementation, Figure 2 As shown, along the second direction B, the glue spot 40 is at least partially disposed between two adjacent fine grids 20 ; along the direction perpendicular to the plane where the battery cell 10 is located, there is a gap between the connecting line 30 and the two fine grids 20 closest to the glue spot 40 along the second direction B.

[0079] During the processing of the battery string, the glue point 40 is usually arranged between two adjacent fine grids 20. Of course, there is also a situation where a part of the glue point 40 is between two adjacent fine grids 20 and the other part is arranged on an adjacent fine grid 20.

[0080] like Figure 2 As shown, along the direction perpendicular to the plane where the battery cell 10 is located, there is a gap between the connecting line 30 and the two fine grids 20 closest to the glue point 40 along the second direction B. More specifically, there is a gap between the arched section 31 of the connecting line 30 and the two fine grids 20 closest to the glue point 40 along the second direction B. In other words, the arched section 31 in the embodiment of the present application is not connected to the fine grids 20 on both sides of the corresponding glue point 40.

[0081] Preferably, if Figure 2 As shown, along the second direction B, there is a first gap between two adjacent fine grids 20, and the glue dots 40 are arranged in the first gap.

[0082] like Figure 2 As shown, as a preferred embodiment, a glue dot 40 is disposed in the first gap between two adjacent fine grids 20 along the second direction B. The glue dot 40 is usually not conductive, and the glue dot 40 is disposed in the first gap between two adjacent fine grids 20 to prevent the glue dot 40 from affecting the electrical connection between the connecting line 30 and the fine grid 20.

[0083] As an optional implementation, Figure 5 and Figure 7 As shown, the connection line 30 includes a connection line substrate 33 and a metal layer 34 attached to the surface of the connection line substrate 33 , wherein the metal layer 34 close to the side of the battery cell 10 is electrically connected to the plurality of fine grids 20 .

[0084] like Figure 5 and Figure 7 As shown, the connecting wire 30 includes a connecting wire substrate 33 and a metal layer 34 attached to the surface of the connecting wire substrate 33. The connecting wire substrate 33 and the metal layer 34 are both conductive. The connecting wire substrate 33 is usually a copper strip. Of course, it can also be other metal strips, such as aluminum strips, etc. There is no specific limitation on this.

[0085] In the embodiment of the present application, the metal layer 34 close to one side of the battery cell 10 is electrically connected to the plurality of fine grids 20 , so that the connection line 30 is electrically connected to the plurality of fine grids 20 , and the current collected by the plurality of fine grids 20 is collected.

[0086] As an optional implementation, Figure 8 As shown, the cell 10 further includes a TCO layer 11 , wherein the metal layer 34 of the horizontal section 32 of the connection line 30 close to one side of the cell 10 abuts against the TCO layer 11 .

[0087] like Figure 8 As shown, a TCO layer, also called a transparent conductive layer, is provided on the side of the cell 10 close to the connection line 30. The metal layer 34 of the horizontal section 32 of the connection line 30 close to the side of the cell 10 abuts against the TCO layer 11. Thus, the horizontal section 32 of the connection line 30 is electrically connected to the TCO layer 11 of the cell 10, so that the current generated by the cell 10 is collected through the horizontal section 32 of the connection line 30.

[0088] As an optional implementation, Figure 7 As shown, along a direction perpendicular to the plane where the cell 10 is located, the fine grid 20 is at least partially embedded in the metal layer 34 on the side of the horizontal section 32 of the connecting line 30 close to the cell 10 .

[0089] Reference Figure 7 , shows a partial cross-sectional view of the horizontal section 32 of the connecting line 30 in the embodiment of the present application. Figure 7 As shown, along a direction perpendicular to the plane where the battery cell 10 is located, the fine grid 20 is partially embedded in the metal layer 34 on the side of the horizontal section 32 of the connecting line 30 close to the battery cell 10, so that the electrical connection between the fine grid 20 and the connecting line 30 is more reliable, so that the current collected by the fine grid 20 can be collected through the connecting line 30.

[0090] As an optional implementation, the melting point of the metal layer 34 is less than 165 degrees. In the embodiment of the present application, the melting point of the metal layer 34 is set to be less than 165 degrees. Thus, during the lamination process of the battery string, the metal layer 34 can be alloyed and interconnected with the fine grid 20.

[0091] Specifically, the metal layer 34 may be a tin-lead-bismuth layer, a tin-bismuth-silver layer, or a tin-indium layer. Of course, the metal layer 34 may also be other metal layers with a melting point less than 165 degrees and conductivity. This application does not impose too many restrictions on this. In actual use, technicians can select a suitable metal layer 34 as needed.

[0092] As an optional implementation, the projection of the arc-shaped protrusion in the plane direction where the battery cell 10 is located is a circle, and the diameter of the circle is greater than or equal to 1 mm and less than or equal to 2 mm.

[0093] In the embodiment of the present application, when the projection of the arc-shaped protrusion in the plane direction where the battery cell 10 is located is a circle, the diameter of the circle is set to be greater than or equal to 1 mm and less than or equal to 2 mm, so that during the processing of the battery string, the glue point 40 can more stably connect the connecting wire 30 to the surface of the battery cell 10.

[0094] For example, the diameter of the circle can be set to 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2 mm, etc. This application does not impose any specific limitation on this, and in the actual processing process, technicians can set it as needed.

[0095] As an optional embodiment, the dimensions of the battery cell 10 include: (182±2) mm*(96±1) mm, (192±2) mm*(91±1) mm, (182±2) mm*(91±1) mm, (182±2) mm*(105±1) mm.

[0096] Optionally, the battery cell 10 may be a rectangular structure, and specific dimensions of the rectangular structure of the battery cell 10 may include: (182±2)mm*(96±1)mm, (192±2)mm*(91±1)mm, (182±2)mm*(91±1)mm, (182±2)mm*(105±1)mm, and the like.

[0097] Of course, in the embodiment of the present application, there is no limitation on the specific structure and size of the battery cell 10, and any structure and any size of the battery cell 10 are within the protection scope of the present application. In actual use, technicians can select a suitable battery cell as the battery cell 10 as needed.

[0098] The present application provides a battery string, the battery string comprising: a battery cell, the battery cell is provided with a plurality of fine grids extending in a first direction and arranged at intervals in a second direction; a plurality of connecting wires, the plurality of connecting wires extending in the second direction and arranged at intervals in the first direction, each of the connecting wires being connected to the surface of the battery cell through a plurality of glue points arranged at intervals, the second direction being perpendicular to the first direction; wherein, along the direction perpendicular to the plane where the battery cell is located, the glue point is an arc-shaped protrusion, the height of the arc-shaped protrusion is less than or equal to 200μm, and along the first direction and the second direction, the length of the arc-shaped protrusion is greater than or equal to 1mm and less than or equal to 2mm. The battery string provided in the embodiment of the present application connects the connecting wire to the surface of the battery cell through a plurality of glue points arranged at intervals, the glue point is an arc-shaped protrusion, the height of the arc-shaped protrusion is less than or equal to 200μm, and along the first direction and the second direction, the length of the arc-shaped protrusion is greater than or equal to 1mm and less than or equal to 2mm. During the processing of the battery string, the glue point can connect the connecting wire to the surface of the battery cell more firmly, so that the distance between the connecting wire connected to the glue point and the surface of the battery cell is moderate. The connecting wire can be connected to more fine grids to collect more current collected by the fine grids, thereby improving the photoelectric conversion efficiency of the battery string. The connecting wire connected to the glue point will not be far away from the surface of the battery cell, making it impossible for the connecting wire to connect to the multiple fine grids on both sides of the glue point, and the connecting wire will not be unable to collect the current collected by the multiple fine grids on both sides of the glue point.

[0099] like Figures 5 to 8 As shown, an embodiment of the present application further provides a photovoltaic module, which includes a cover plate 50, a first adhesive layer 60, a plurality of battery strings described in the above embodiments, a second adhesive layer, and a back plate which are arranged in sequence, wherein the plurality of battery strings are arranged at intervals.

[0100] The cover plate 50 is connected to one side of the battery string through a first adhesive layer 60 , and the back plate is connected to the other side of the battery string through a second adhesive layer.

[0101] It should be noted that in the embodiment of the present application, the battery string included in the photovoltaic module has the same structure as the battery string described in the above embodiment, and its beneficial effects are also similar, which will not be repeated here.

[0102] As an optional implementation, the first adhesive layer 60 and / or the second adhesive layer is a multi-layer composite adhesive layer.

[0103] like Figures 5 to 8 As shown, the first adhesive layer 60 and / or the second adhesive layer in the embodiment of the present application adopts a multi-layer composite adhesive layer, and the multi-layer composite adhesive layer may include an EVA layer and a POE layer.

[0104] The EVA layer is an ethylene-vinyl acetate copolymer layer, which has water resistance, corrosion resistance, and is easy to process by hot pressing, cutting, gluing, laminating, etc. The POE layer is a polymer layer of ethylene and octene, or a polymer layer of ethylene and butene.

[0105] As an optional implementation, the multi-layer composite adhesive layer is a double-layer structure, including an EVA layer 61 and a POE layer 62 stacked in sequence.

[0106] like Figures 5 to 8 As shown, the multi-layer composite adhesive layer is a double-layer structure, including an EVA layer 61 and a POE layer 62 stacked in sequence. Among them, the EVA layer 61 is connected to the battery string, that is, the EVA layer directly contacts the battery string. The EVA layer 61 is easy to be hot-pressed, so that the photovoltaic module can be hot-pressed and formed by hot-pressing.

[0107] As an optional implementation, the multi-layer composite adhesive layer is a three-layer structure, including an EVA layer 61, a POE layer 62 and an EVA layer 61 stacked in sequence.

[0108] The multi-layer composite adhesive layer in the embodiment of the present application can also be a three-layer structure, including an EVA layer 61, a POE layer 62 and an EVA layer 61 stacked in sequence. One of the EVA layers 61 is connected to the battery string, and the other EVA layer 61 is connected to the cover plate 50 or the back plate. In order to facilitate the use of hot pressing, the cover plate 50 is connected to one side of the battery string through the multi-layer composite adhesive layer, and the back plate is connected to the other side of the battery string through the multi-layer composite adhesive layer.

[0109] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0110] Although the optional embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including optional embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0111] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity from another entity, and do not necessarily require or imply any such actual relationship or order between these entities. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that an article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such article or terminal device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the article or terminal device including the elements.

[0112] The technical solution provided by the present invention is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. At the same time, for those skilled in the art, according to the principle and implementation mode of the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A battery string, characterized in that: include: A battery cell, wherein a plurality of fine grids extending along a first direction and arranged at intervals along a second direction are provided on the battery cell; a plurality of connection lines extending along the second direction and arranged at intervals along the first direction, each of the connection lines being connected to the surface of the battery cell through a plurality of glue points arranged at intervals, and the second direction being perpendicular to the first direction; Among them, along the direction perpendicular to the plane where the battery cell is located, the glue point is an arc-shaped protrusion, the height of the arc-shaped protrusion is less than or equal to 200μm, and along the first direction and the second direction, the length of the arc-shaped protrusion is greater than or equal to 1mm and less than or equal to 2mm.

2. The battery string according to claim 1, characterized in that: Along a direction perpendicular to the plane where the battery sheet is located, each of the connecting lines is at least partially embedded in a plurality of the glue points spaced apart along the second direction.

3. The battery string according to claim 2, characterized in that: Along a direction perpendicular to the plane where the battery sheet is located, the depth of the connecting line embedded in the glue spot accounts for 40% to 100% of the height of the glue spot.

4. The battery string according to claim 1, characterized in that: A cross section of the connecting line along the second direction is a wavy structure.

5. The battery string according to claim 4, characterized in that: Along the second direction, the connection line connected to the glue point forms an arched section, and a distance between a side of the arched section close to the battery cell and a surface of the battery cell is less than or equal to 200 um.

6. The battery string according to claim 5, characterized in that: Along the second direction, the arched segment spans over two adjacent fine grids.

7. The battery string according to claim 6, characterized in that: Along the second direction, the connection line between two adjacent arched segments is a horizontal segment, the horizontal segment is connected to the surface of the battery cell, and the horizontal segment is electrically connected to at least one of the fine grids.

8. The battery string according to claim 7, characterized in that: Along a direction perpendicular to the plane where the battery cell is located, the connecting line has a first projection on the battery cell, and the length of the first projection is L1; Along the second direction, the sum of the lengths of the horizontal segments is L2, wherein 0.7L1≤L2≤0.9L1.

9. The battery string according to claim 1, characterized in that: Along the second direction, the glue dots are at least partially disposed between two adjacent fine grids; Along a direction perpendicular to the plane where the battery sheet is located, there is a gap between the connecting line and two of the fine grids that are closest to the glue point along the second direction.

10. The battery string according to claim 1, characterized in that: Along the second direction, there is a first gap between two adjacent fine grids, and the glue dots are arranged in the first gap.

11. The battery string according to claim 7, characterized in that: The connecting wire comprises a connecting wire substrate and a metal layer attached to the surface of the connecting wire substrate, wherein: The metal layer close to one side of the battery cell is electrically connected to a plurality of the fine grids.

12. The battery string according to claim 11, characterized in that: The cell further comprises: a TCO layer, wherein: The metal layer of the horizontal section of the connecting line close to one side of the battery cell abuts against the TCO layer.

13. The battery string according to claim 11, characterized in that: Along a direction perpendicular to the plane where the battery cell is located, the fine grid is at least partially embedded in the metal layer on a side of the horizontal section of the connecting line close to the battery cell.

14. The battery string according to claim 13, characterized in that: The melting point of the metal layer is less than 165 degrees.

15. The battery string according to claim 13, characterized in that: The metal layer is one of a tin-lead-bismuth layer, a tin-bismuth-silver layer or a tin-indium layer.

16. The battery string according to claim 1, characterized in that: The projection of the arc-shaped protrusion in the direction of the plane where the battery sheet is located is a circle, and the diameter of the circle is greater than or equal to 1 mm and less than or equal to 2 mm.

17. The battery string according to claim 1, characterized in that: The sizes of the battery cells include: (182±2)mm*(96±1)mm, (192±2)mm*(91±1)mm, (182±2)mm*(91±1)mm, and (182±2)mm*(105±1)mm.

18. A photovoltaic module, characterized in that: It comprises a cover plate, a first adhesive layer, a plurality of battery strings according to any one of claims 1 to 17, a second adhesive layer, and a back plate which are arranged in sequence, wherein the plurality of battery strings are arranged at intervals.

19. The photovoltaic module according to claim 18, wherein the first adhesive layer and / or the second adhesive layer is a multi-layer composite adhesive layer. 20 . The photovoltaic module according to claim 19 , wherein the multi-layer composite adhesive layer is a double-layer structure, comprising an EVA layer and a POE layer stacked in sequence. 21 . The photovoltaic module according to claim 19 , wherein the multi-layer composite adhesive layer is a three-layer structure, comprising an EVA layer, a POE layer and an EVA layer stacked in sequence. 22 . The photovoltaic module according to claim 20 or 21 , wherein the EVA layer directly contacts the cell string.

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