A battery piece and a photovoltaic module

Abstract

The application relates to the technical field of solar cells, in particular to a cell piece and a photovoltaic module. The cell piece comprises a body, an edge grid line and an internal grid line, the edge grid line surrounds an inner side area, the internal grid line is located in the inner side area, an area between the edge grid line and the edge of the body is an outer side area, the outer side area is provided with a connecting grid line, one end of the connecting grid line is connected with the edge of the body, and the other end of the connecting grid line is connected with the edge grid line. The connecting grid line can collect the current of the body in the outer side area, and the connecting grid line can transmit the collected current to the edge grid line, and finally transmit the current to a solder strip through the edge grid line and the internal grid line, so that the collection and transmission of the current of the outer side area are realized, the output power of the cell piece can be improved, and the output power of the photovoltaic module can be improved. Meanwhile, the connecting grid line arranged in the outer side area also reduces the risk of ash and darkness of the outer side area, and the uniformity of the overall brightness of the cell piece can be improved.

Description

Technical Field

[0001] This application relates to the field of solar cell technology, and more particularly to a solar cell and a photovoltaic module. Background Technology

[0002] A photovoltaic module consists of multiple solar cells, which are used to convert light energy into electrical energy to meet the electricity needs of daily production.

[0003] The solar cell includes a body and internal grid lines disposed on the body. The internal grid lines are used to collect the current on the solar cell, and the solder ribbons connected to the internal grid lines can collect and transmit the current to realize the output of the solar cell's current.

[0004] Typically, the size of the internal grid lines is smaller than the size of the main body, resulting in a smaller coverage area of ​​the internal grid lines on the main body. This leads to lower output power of the solar cell, and the parts of the main body without internal grid lines will appear grayish and dark, resulting in uneven overall brightness of the solar cell.

[0005] Therefore, improving the output power and brightness uniformity of solar cells is an important problem that needs to be solved in this field. Summary of the Invention

[0006] This application provides a solar cell and a photovoltaic module that can improve the output power and brightness uniformity of the solar cell.

[0007] This application provides a battery cell, which includes a body. Along the circumference of the body in a plane perpendicular to its thickness direction, the body includes multiple ends. The battery cell also includes edge grid lines and connecting grid lines. The region between the edge grid lines and the edge of the body is an outer region. The connecting grid lines are located in the outer region, with one end connected to the edge of the body and the other end connected to the edge grid lines. The line connecting the endpoint of the edge grid line and its adjacent end forms a vertex line of the body, and at least a portion of the connecting grid lines are parallel to the vertex line.

[0008] In some possible designs, the connecting grid lines include multiple first connecting lines, which are parallel to the vertex connecting lines and are spaced apart along a first direction and / or a second direction.

[0009] In some possible designs, the connecting grid lines also include a second connecting line located between adjacent first connecting lines. The two ends of the second connecting line are connected to the edge grid line and the edge of the body, respectively, and the two ends of the second connecting line are also connected to adjacent first connecting lines.

[0010] In some possible designs, the first connecting line and the second connecting line are of equal length.

[0011] In some possible designs, the edge grid lines include a first grid line extending along a first direction and a second grid line extending along a second direction, the first and second grid lines enclosing an inner region. A connecting grid line is disposed between the second grid line and the edge of the body. The edge grid lines enclosing the inner region also include internal grid lines extending along the first direction and arranged along the second direction, the internal grid lines located within the inner region. The internal grid lines intersect the second grid lines at a first intersection point, and multiple first intersection points are arranged along the second direction. The first connecting line, the second connecting line, and the second grid line intersect at a second intersection point, and multiple second intersection points are arranged along the second direction. At least one first intersection point coincides with a second intersection point.

[0012] In some possible designs, the first connecting line includes a corner connecting line, one end of which is connected to the endpoint of the edge grid line, and the other end of which is connected to the end of the body. The corner connecting line coincides with the vertex connecting line.

[0013] In some possible designs, the outer region includes a first region and a second region arranged along a first direction, with connecting grid lines provided in both the first and second regions.

[0014] In some possible designs, the connecting grid lines in the first region are symmetrically arranged with respect to the connecting grid lines in the second region, with the axis of symmetry parallel to a second direction. Alternatively, the connecting grid lines in the first region are centrally symmetrically arranged with respect to the connecting grid lines in the second region.

[0015] In some possible designs, the edge grid lines include first grid lines extending along a first direction and arranged along a second direction. A portion of the connecting grid lines is located between the first grid lines and the edge of the body.

[0016] In some possible designs, in the second direction, between the edge of the first gate line and the body, the outer region includes a clearance area for placing solder strips. The clearance area does not have connecting gate lines.

[0017] In some possible designs, the vertical distance between the edge grid line and the edge of the body is L, where 0 < L ≤ 1.2 mm.

[0018] In some possible designs, the body includes a light-facing surface and a back-lighting surface arranged along its thickness direction, both of which are provided with edge grid lines and internal grid lines. The connecting grid lines are located on the light-facing surface and / or the back-lighting surface of the body.

[0019] A second aspect of this application provides a photovoltaic module, which includes a cover plate, an encapsulation layer, and a cell layer, with the encapsulation layer located between the cover plate and the cell layer. The cell layer includes the cells described in any of the above claims, and further includes solder ribbons electrically connected to the internal grid lines of the cells, with adjacent cells electrically connected to each other via the solder ribbons.

[0020] In this application, connecting grid lines are provided on the outer region of the main body. These connecting grid lines can collect the current in the outer region of the main body and transmit the collected current to the edge grid lines. Finally, the current is transmitted to the solder ribbon via the edge grid lines and the inner grid lines. This achieves the collection and transmission of current in the outer region, which can improve the output power of the solar cell and thus the output power of the photovoltaic module. At the same time, providing connecting grid lines in the outer region reduces the area without grid lines, thereby reducing the risk of graying or darkening in the outer region and improving the uniformity of the overall brightness of the solar cell.

[0021] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 The photovoltaic module provided in this application is shown in some embodiments as a structural cross-sectional view. Figure 2 This is a partial structural diagram of the battery layer in some embodiments; Figure 3 for Figure 2 A schematic diagram of the structure of the battery cell in some embodiments; Figure 4 for Figure 3 Enlarged view of part A in some embodiments; Figure 5 for Figure 3 Enlarged view of part A in some other embodiments; Figure 6 for Figure 3 Enlarged view of part A in some other embodiments; Figure 7 for Figure 3 Enlarged view of part A in some embodiments; Figure 8 A schematic diagram of the structure of the battery cell provided in this application in some embodiments; Figure 9 for Figure 8 Enlarged views of part B in some embodiments; Figure 10 for Figure 8 Enlarged view of part B in some other embodiments; Figure 11 Schematic diagrams of the structure of the battery cell provided in this application in other embodiments; Figure 12 A schematic diagram of the structure of the battery cell provided in this application in some other embodiments; Figure 13 This is a schematic diagram of the connection structure between the battery cell and the solder strip; Figure 14 for Figure 13 A schematic diagram of the structure of the battery cells.

[0024] Figure label: 10-Cover plate; 101-First cover plate; 102-Second cover plate; 20 - Encapsulation layer; 201 - First adhesive film; 202 - Second adhesive film; 30 - Battery layer; 301 - Battery cell; 302 - Welding strip; 1-Body; 11-End; 12-Vertex connection; 2-Edge grid line; 21-First grid line; 22-Second grid line; 23-First intersection point; 24-Second intersection point; 3-Inner fence line; 4-Inner area; 5-Outer area; 51-First area; 52-Second area; 53-Third area; 54-Avoidance area; 6-Connecting grid line; 61-First connecting line; 611-Corner connecting line; 612-Middle connecting line; 62-Second connecting line; X - First direction; Y - Second direction; K - First extension direction; T - Second extension direction. Detailed Implementation

[0025] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0026] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0027] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0028] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0029] The first aspect of this application provides a photovoltaic module, Figure 1 Structural cross-sectional views of the photovoltaic module provided in this application in some embodiments, such as Figure 1 As shown, the photovoltaic module includes a cover plate 10, an encapsulation layer 20, and a cell layer 30.

[0030] The cover plate 10 includes a first cover plate 101 and a second cover plate 102 arranged along the third direction Z. The encapsulation layer 20 and the battery layer 30 are located between the first cover plate 101 and the second cover plate 102. A portion of the encapsulation layer 20 is located between the battery layer 30 and the first cover plate 101, and another portion of the encapsulation layer 20 is located between the battery layer 30 and the second cover plate 102, so as to achieve the encapsulation and fixation of the cover plate 10 and the battery layer 30.

[0031] At least one of the first cover plate 101 and the second cover plate 102 is made of a light-transmitting material, which is beneficial to improving the photoelectric conversion efficiency of the photovoltaic module.

[0032] The first cover plate 101 can be made of one of the following rigid materials: tempered glass, PET (polyethylene terephthalate), or PC (polycarbonate). Alternatively, the first cover plate 101 can be made of one of the following flexible materials: PVF (polyvinyl fluoride), ETFE (ethylene-tetrafluoroethylene copolymer), or PVDF (polyvinylidene fluoride). All of these materials have high light transmittance, ensuring that more light reaches the battery layer, thereby increasing the light absorption of the photovoltaic module and improving its photoelectric conversion efficiency.

[0033] The material of the second cover plate 102 can be one of rigid materials such as tempered glass, PET (polyethylene terephthalate), or PC (polycarbonate). Alternatively, the material of the second cover plate 102 can be one of flexible materials such as PVF (polyvinyl fluoride), ETFE (ethylene-tetrafluoroethylene copolymer), or PVDF (polyvinylidene fluoride).

[0034] The materials of the first cover plate 101 and the second cover plate 102 can be the same or different.

[0035] like Figure 2 As shown, the encapsulation layer 20 includes a first adhesive film 201 and a second adhesive film 202. In the third direction Z, a portion of the structure of the first adhesive film 201 is located between the battery layer 30 and the first cover plate 101, and a portion of the structure of the second adhesive film 202 is located between the battery layer and the second cover plate 102.

[0036] The first encapsulant film 201 is made of one of the following polyolefins: EVA (Ethylene-Vinyl Acetate Copolymer), POE (Polyolefin Elastomer), or PVB (Polyvinyl Butyral). These materials have high light transmittance, which is beneficial for improving the photoelectric conversion efficiency of photovoltaic modules. The first encapsulant film 201 can also be an EPE film (EVA-POE-EVA co-extrusion structure) or an EP film (EVA-POE co-extrusion structure).

[0037] The material of the second film 202 is one of polyolefins such as EVA (Ethylene-Vinyl Acetate Copolymer), POE (Polyolefin Elastomer), and PVB (Polyvinyl Butyral). The second film 202 can also be an EPE film (EVA-POE-EVA co-extrusion structure) or an EP film (EVA-POE co-extrusion structure).

[0038] The materials of the first adhesive film 201 and the second adhesive film 202 can be the same or different.

[0039] Figure 2 This is a partial structural diagram of the battery layer in some embodiments. For example... Figure 2As shown, the battery layer 30 includes a plurality of battery cells 301. In the first direction X, adjacent battery cells 301 are electrically connected by solder strips 302 to form a battery string 303. The thickness direction of the battery cells 301 is parallel to the aforementioned third direction Z.

[0040] The types of solar cells include, but are not limited to, PaWWivated Emitter RearCell (PERC), Tunnel Oxide PaWWivated Contact (TOPCon), Intrinsic Thin-Film Heterojunction (HJT), and perovskite solar cells.

[0041] For PERC cells, along their thickness direction, the PERC cell sequentially includes a front surface silver electrode, a front surface silicon nitride passivation layer, a phosphorus emitter layer, a P-type substrate silicon layer, a local aluminum back field, a metallic aluminum back electrode, and a back passivation layer (Al2O3 / WiNx). PERC cells use a passivation film to passivate the back surface, replacing the all-aluminum back field, enhancing light reflection within the silicon substrate, reducing the recombination rate on the back surface, and improving the cell efficiency by 0.5%-1%.

[0042] For a TOPCon cell, along its thickness direction, it sequentially comprises a silver electrode, a front-surface silicon nitride passivation layer, a boron-doped emitter, an N-type substrate silicon layer, a diffused doped layer, an ultrathin silicon oxide layer, doped polycrystalline silicon, silicon nitride, and a silver electrode. The back of the cell consists of an ultrathin silicon oxide layer (1nm~2nm) and a phosphorus-doped microcrystalline-amorphous hybrid Wi film, which together form a passivation contact structure. This structure blocks minority carrier recombination, increasing the cell's open-circuit voltage and short-circuit current. The ultrathin oxide layer allows majority carrier electrons to tunnel into the polycrystalline silicon layer while blocking minority carrier recombination. The excellent passivation effect of the ultrathin silicon oxide and heavily doped silicon film causes band bending on the silicon wafer surface, creating a field passivation effect. This significantly increases the probability of electron tunneling, reduces contact resistance, and improves the cell's open-circuit voltage and short-circuit current, thereby increasing the cell's conversion efficiency.

[0043] For an HJT cell, along its thickness direction, the HJT cell sequentially includes a front low-temperature silver electrode, a front conductive film, an N-type amorphous silicon film, an intrinsic amorphous silicon film, an N-type substrate silicon layer, an intrinsic amorphous silicon film, a P-type amorphous silicon film, a back conductive film, and a back low-temperature silver electrode.

[0044] For a perovskite solar cell, along its thickness direction, it sequentially comprises a substrate material, a conductive thin film, an electron transport layer (titanium dioxide), a perovskite absorption layer (hole transport layer), and a metal cathode. Perovskite materials possess a high light absorption coefficient and a long carrier diffusion distance. After the photons absorbed by the perovskite material are converted into electrons, they are easily collected by the electrodes with minimal loss, thus generating high photogenerated voltage and current, resulting in high photoelectric conversion efficiency.

[0045] The following discussion uses cell 301 as an example of a TOPCon cell to illustrate the specific structure of the cell.

[0046] Figure 3 This is a schematic diagram of the structure of the battery cell 301 in some embodiments. Figure 3 The example illustrates the light-facing surface of solar cell 301. For example... Figure 3 As shown, the battery cell 301 includes a body 1, and in a plane perpendicular to the thickness direction of the body 1, along the circumference of the body 1, the body 1 includes a plurality of ends 11.

[0047] It should be noted that the circumferential direction of the body 1 refers to the direction around the body 1 along the outer edge of the body 1's outline, and the end 11 of the body 1 refers to the corner position of the body 1.

[0048] The main body 1 is provided with grid lines, which are used to electrically connect with the solder strip 302.

[0049] like Figure 3 As shown, the grid line includes an edge grid line 2, which includes a first grid line 21 extending along the first direction X and arranged along the second direction Y. The edge grid line 2 also includes a second grid line 22 extending along the second direction Y and arranged along the first direction X. The first grid line 21 and the second grid line 22 form an inner region 4, and the region between the edge grid line 2 and the edge of the body 1 is the outer region 5.

[0050] like Figure 3 As shown, the grid line also includes an inner grid line 3, which extends along the first direction X and is spaced apart along the second direction Y. The inner grid line 3 is located in the inner region 4.

[0051] The first grid line 21 and the second grid line 22 can be connected or have a gap.

[0052] Figure 4 for Figure 3 Part A in the image is shown as an enlarged view in some embodiments. For example... Figure 4 As shown, the first gate line 21 and the second gate line 22 are connected.

[0053] In some embodiments, the intersection of the first gate line 21 and the second gate line 22 coincides with the end 11 of the first gate line 21, and the intersection of the first gate line 21 and the second gate line 22 coincides with the end 11 of the second gate line 22.

[0054] In some embodiments, the intersection of the first gate line 21 and the second gate line 22 coincides with the end 11 of the first gate line 21, and the intersection of the first gate line 21 and the second gate line 22 does not coincide with the end 11 of the second gate line 22.

[0055] In some embodiments, the intersection of the first gate line 21 and the second gate line 22 does not coincide with the end 11 of the first gate line 21, but the intersection of the first gate line 21 and the second gate line 22 coincides with the end 11 of the second gate line 22.

[0056] In some embodiments, the intersection of the first gate line 21 and the second gate line 22 does not coincide with the end 11 of the first gate line 21, and the intersection of the first gate line 21 and the second gate line 22 does not coincide with the end 11 of the second gate line 22.

[0057] Figure 4 The example shows that the intersection of the first gate line 21 and the second gate line 22 coincides with the end 11 of the first gate line 21, and the intersection of the first gate line 21 and the second gate line 22 coincides with the end 11 of the second gate line 22.

[0058] Figure 5 for Figure 3 Enlarged views of part A in other embodiments. For example... Figure 5 As shown, there is a gap between the first gate line 21 and the second gate line 22, that is, the first gate line 21 and the second gate line 22 are not connected.

[0059] In some embodiments, such as Figure 5 As shown, the end 11 of the second gate line 22 is aligned with the first gate line 21 in the first direction X.

[0060] In some embodiments, such as Figure 6 As shown, the end 11 of the second gate line 22 is not aligned with the first gate line 21 in the first direction X, and in the second direction Y, the first gate line 21 is located on the side of the second gate line 22 near the edge of the body 1.

[0061] In some embodiments, such as Figure 7 As shown, the end 11 of the second gate line 22 is not aligned with the first gate line 21 in the first direction X, and in the second direction Y, the first gate line 21 is located on the side of the second gate line 22 facing the inner gate line 3.

[0062] The embodiments of this application do not impose any special limitations on the connection relationship, positional relationship, etc. of the first gate line 21 and the second gate line 22.

[0063] When the body 1 has a chamfer, the first grid line 21 can be bent along the inclined direction of the chamfer, and the second grid line 22 can also be bent along the inclined direction of the chamfer.

[0064] Refer again Figure 3 The size of the internal grid line 3 in the first direction X is smaller than the size of the body 1 in the first direction X, and the distribution area of ​​the internal grid line 3 in the second direction Y is smaller than the size of the body 1 in the second direction Y. That is, the outer area 5 of the battery cell 301 is not provided with grid lines, which makes the coverage area of ​​the grid lines on the body 1 smaller, resulting in a lower output power of the battery cell 301. In addition, the outer area 5 without grid lines will appear gray and dark, resulting in uneven overall brightness of the battery cell 301.

[0065] Therefore, in the embodiments of this application, such as Figure 8 As shown, the battery cell 301 provided in this application embodiment also includes a connecting grid line 6. The connecting grid line 6 is located in the outer region 5 of the body 1, and one end of the connecting grid line 6 is connected to the edge of the body 1, and the other end of the connecting grid line 6 is connected to the edge grid line 2.

[0066] In the first direction X, the connecting grid line 6 can be located on one or both sides of the inner region 4. In the second direction Y, the connecting grid line 6 can be located on one or both sides of the inner region 4.

[0067] In this embodiment, a connecting grid line 6 is provided in the outer region 5 of the main body 1. The connecting grid line 6 can collect the current of the main body 1 in the outer region 5, and can transmit the collected current to the edge grid line 2. Finally, it is transmitted to the solder ribbon 302 through the edge grid line 2 and the inner grid line 3, thereby realizing the collection and transmission of current in the outer region 5, which can improve the output power of the solar cell 301, and thus improve the output power of the photovoltaic module. At the same time, providing the connecting grid line 6 in the outer region 5 reduces the area without grid lines, thereby reducing the risk of graying or darkening in the outer region 5, and improving the uniformity of the overall brightness of the solar cell 301.

[0068] Figure 9 for Figure 8 Part B in the diagram is an enlarged view in some embodiments. For example... Figure 9 As shown, the line connecting the endpoint of the edge grid line 2 and its adjacent end 11 is the vertex line 12 of the body 1, and at least part of the connecting grid line 6 is parallel to the vertex line 12.

[0069] In this embodiment, at least some of the connecting grid lines 6 are parallel to the vertex connecting lines 12. During the processing of the connecting grid lines 6, the endpoints of the edge grid lines 2 and their adjacent ends 11 can be used as reference points, thereby improving the accuracy of the tilt angle of the connecting grid lines 6. This will help improve the accuracy of parameters such as the number, position, and angle of the connecting grid lines 6, and also reduce the gap between the actual output power and the target output power of the battery cell 301, thereby improving the processing yield of the battery cell 301.

[0070] like Figure 9 As shown, the connecting grid line 6 includes a plurality of first connecting lines 61. The extension direction of the first connecting lines 61 is denoted as the first extension direction K. The first extension direction K is parallel to the vertex connecting line 12, and the plurality of first connecting lines 61 are arranged at intervals along the first direction X and / or the second direction Y.

[0071] Among them, vertex connection 12 may coincide with one of the first connecting lines 61, or may not coincide.

[0072] like Figure 9 As shown, the first connecting line 61 includes a corner connecting line 611 and a middle connecting line 612. The corner connecting line 611 and the middle connecting line 612 are arranged at intervals along the first direction X and / or the second direction Y, and along the first extension direction K, one end of the corner connecting line 611 coincides with the end 11 of the body 1, and the other end of the corner connecting line 611 coincides with the end point of the edge grid line 2, that is, the corner connecting line 611 coincides with the vertex connecting line 12.

[0073] In this embodiment, setting a corner connecting line 611 that coincides with the vertex connecting line 12 can further increase the accuracy of the position and angle of the first connecting line 61, thereby further reducing the gap between the actual output power and the target output power of the battery cell 301, and further improving the processing yield of the battery cell 301.

[0074] like Figure 9 As shown, the connecting grid line 6 may also include a second connecting line 62, which is located between adjacent first connecting lines 61. The extension direction of the second connecting line 62 is denoted as the second extension direction T, which intersects with the first extension direction K.

[0075] In this embodiment, by setting second connecting lines 62 with different tilt directions between adjacent first connecting lines 61, the number of connecting grid lines 6 set in the outer region 5 can be increased, thereby improving the current collection efficiency of the outer region 5 of the battery cell 301 and thus improving the output power of the battery cell 301.

[0076] like Figure 9As shown, the two ends of the second connecting line 62 are connected to the edge grid line 2 and the edge of the body 1, respectively, and the two ends of the second connecting line 62 are connected to the adjacent first connecting line 61, respectively. That is, one end of the second connecting line 62, the edge of the body 1 and the first connecting line 61 intersect at the same point, and the other end of the second connecting line 62, the first connecting line 61 and the edge grid line 2 intersect at the same point.

[0077] In this embodiment, one end of the second connecting line 62, the edge of the body 1, and the first connecting line 61 intersect at the same point, and the other end of the second connecting line 62, the first connecting line 61, and the edge grid line 2 intersect at the same point. This can increase the arrangement density of the first connecting line 61 and the second connecting line 62, so as to further increase the number of connecting grid lines 6 provided in the outer region 5, further improve the current collection efficiency of the outer region 5 of the battery cell 301, and further improve the output power of the battery cell 301.

[0078] The lengths of the first connecting line 61 and the second connecting line 62 are equal. It should be noted that the length of the first connecting line 61 refers to the length of the first connecting line 61 extending in the first extending direction K, and the length of the second connecting line 62 refers to the length of the second connecting line 62 extending in the second extending direction T.

[0079] In this embodiment, the lengths of the first connecting line 61 and the second connecting line 62 are equal, so that the first connecting line 61, the second connecting line 62 and the edge of the body 1 form an isosceles triangle, and the first connecting line 61, the second connecting line 62 and the edge grid line 2 also form an isosceles triangle, thereby improving the uniformity of the arrangement of the first connecting line 61 and the second connecting line 62, and further improving the uniformity of current collection in the outer region 5 by the connecting grid line 6, which can improve the brightness uniformity of the battery cell 301.

[0080] like Figure 9 As shown, the angle between the first extension direction K and the first direction X is α1, and the angle between the second extension direction T and the first direction X is α2. Since α1 and α2 are equal, the first connecting line 61, the second connecting line 62 and the edge of the body 1 form an equilateral triangle. The first connecting line 61, the second connecting line 62 and the edge grid line 2 also form an equilateral triangle, which further improves the uniformity of the arrangement of the first connecting line 61 and the second connecting line 62, and further improves the uniformity of current collection in the outer region 5 by the connecting grid line 6, which can further improve the brightness uniformity of the battery cell 301.

[0081] The aforementioned connecting grid line 6 can be located between the first grid line 21 and the edge of the body 1, or it can be located between the second grid line 22 and the edge of the body 1.

[0082] like Figure 8 and Figure 9As shown, the aforementioned connecting grid line 6 is provided between the second grid line 22 and the edge of the body 1.

[0083] like Figure 9 As shown, the inner grid line 3 intersects the second grid line 22 at a first intersection point 23, and multiple first intersection points 23 are arranged along the second direction Y. The first connecting line 61, the second connecting line 62, and the second edge grid line 2 intersect at a second intersection point 24, and multiple second intersection points 24 are arranged along the second direction Y.

[0084] The first intersection point 23 and the second intersection point 24 can be staggered along the second direction Y, or the first intersection point 23 and the second intersection point 24 can coincide.

[0085] Figure 9 The example shows that the first intersection point 23 and its adjacent second intersection point 24 are staggered along the second direction Y, that is, the first intersection point 23 and its adjacent second intersection point 24 have no overlapping parts.

[0086] Alternatively, some of the first intersection points 23 and their adjacent second intersection points 24 do not overlap, while other parts of the first intersection points 23 and their adjacent second intersection points 24 overlap or even completely overlap.

[0087] Alternatively, the number of second intersection points 24 is not less than the number of first intersection points 23, and all the first glue points coincide with the second glue points.

[0088] Figure 10 for Figure 8 Enlarged view of part B in other embodiments. Figure 10 The example shows that at least one first intersection point 23 coincides with a second intersection point 24.

[0089] In this embodiment, the first intersection point 23 and the adjacent second intersection point 24 are staggered along the second direction Y, which can reduce the current at the first intersection point 23 and the second intersection point 24, thereby reducing the current loss on the edge grid line 2, so as to improve the output power of the battery cell 301.

[0090] The first intersection point 23 and the second intersection point 24 coincide, so that the current on the connecting grid line 6 can be directly transmitted to the inner grid line 3 through the overlapping first intersection point 23 and the second intersection point 24. This shortens the transmission path of the current on the connecting grid line 6 on the edge grid line 2, reduces the damage of the current transmission on the edge grid line 2, and can also improve the output power of the battery cell 301.

[0091] like Figure 8 As shown, the outer region 5 includes a first region 51 and a second region 52 arranged along the first direction X, and at least one of the first region 51 and the second region 52 is provided with the aforementioned connecting grid line 6.

[0092] Figure 8 The example shows that the first region 51 is provided with the aforementioned connecting grid line 6.

[0093] Figure 11 This is a schematic diagram of the structure of the battery cell 301 in some other embodiments. Figure 11 The example shows that the aforementioned connecting grid line 6 is provided in both the first region 51 and the second region 52.

[0094] In this embodiment, connecting grid lines 6 are provided in both the first region 51 and the second region 52, which increases the area of ​​the connecting grid lines 6 and further improves the current collection efficiency at the edge of the battery cell 301, thereby further improving the output power of the battery cell 301. Furthermore, connecting grid lines 6 are provided on both sides of the battery cell 301 in the first direction X, which improves the brightness uniformity of both sides of the battery cell 301 in the first direction X.

[0095] In some embodiments, the connecting grid line 6 in the first region 51 and the connecting grid line 6 in the second region 52 are arranged symmetrically, with the axis of symmetry parallel to the second direction Y.

[0096] In other embodiments, the connecting grid lines 6 in the first region 51 and the connecting grid lines 6 in the second region 52 are arranged symmetrically, and the center of symmetry coincides with the geometric center of the battery cell 301.

[0097] In this embodiment, the connecting grid lines 6 in the first region 51 and the second region 52 are either axially symmetrical or centrally symmetrical, which can improve the brightness uniformity of both sides of the battery cell 301 in the first direction X.

[0098] like Figure 11 As shown, in the second direction Y, a connecting grid line 6 may or may not be provided between the first grid line 21 and the edge of the body 1. For ease of description, the area between the first grid line 21 and the edge of the body 1 is referred to as the third region 53. That is, the third region 53 may or may not have a connecting grid line 6.

[0099] Figure 11 The example shows that no connecting grid line 6 is set in the third region 53.

[0100] Figure 12 The schematic diagram of the structure of the battery cell 301 in some other embodiments is shown. Figure 12 The example shows that a connecting grid line 6 is provided in the third region 53, that is, a portion of the connecting grid line 6 is located between the first grid line 21 and the edge of the body 1.

[0101] In this embodiment, a connecting grid line 6 is provided between the first grid line 21 and the edge of the body 1, which can further increase the setting area of ​​the connecting grid line 6, thereby improving the current collection efficiency at the edge of the battery cell 301 and also improving the overall brightness uniformity of the battery cell 301.

[0102] In the second direction Y, the connecting grid line 6 can be located on one side of the inner region 4 or on both sides of the inner region 4.

[0103] When the inner region 4 is provided with connecting grid lines 6 on both sides in the second direction Y, the connecting grid lines 6 on both sides can be arranged axially symmetrically with the axis of symmetry parallel to the first direction X. The connecting grid lines 6 on both sides can also be arranged centrally symmetrically with the center of symmetry coinciding with the geometric center of the battery cell 301.

[0104] Figure 13 This is a schematic diagram of the connection structure between the battery cell 301 and the solder ribbon 302. Figure 13 As shown, after the solder ribbon 302 is connected and fixed to the battery cell 301, the solder ribbon 302 extending along the second direction Y will come into contact with the third region 53.

[0105] When the connecting grid line 6 is provided in the third region 53, in some embodiments, the solder ribbon 302 can cover the connecting grid line 6, so that the current on the connecting grid line 6 can be directly transmitted to the solder ribbon 302, reducing the loss of current transmission, so as to improve the output power of the battery cell 301.

[0106] When the third region 53 is provided with connecting grid lines 6, in other embodiments, such as Figure 14 As shown, the outer region 5 also includes a clearance region 54, which is located within the third region 53. The clearance region 54 is used to place the solder strip 302, and no connecting grid line 6 is provided in the clearance region 54.

[0107] In this embodiment, the avoidance area 54 is not provided with the connecting grid line 6, which avoids the connecting grid line 6 from contacting the solder ribbon 302. During the welding and fixing process of the solder ribbon 302 and the battery cell 301, the risk of the connecting grid line 6 breaking due to factors such as the force on the solder ribbon 302 and the offset of the solder ribbon 302 is reduced. This reduces the risk of local current not being collected due to the breaking of the connecting grid line 6, thereby improving the output power of the battery cell 301. In addition, the breaking of the connecting grid line 6 will also cause the battery cell 301 to darken and turn black in some areas. Therefore, not providing the connecting grid line 6 in the avoidance area 54 can also improve the brightness uniformity of the battery cell 301.

[0108] The perpendicular distance between edge grid line 2 and the edge of body 1 is L, such as Figure 14As shown, taking the second edge as an example, the vertical distance between the second edge and the edge of the body 1 in the first direction X is L, where 0 < L ≤ 1.2 mm. For example, L can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, etc.

[0109] In this embodiment, if L is large, the area on the battery cell 301 used for arranging the internal grid lines 3 is small, which reduces the output power of the battery cell 301.

[0110] Therefore, 0 < L ≤ 1.2 mm can increase the output power of the solar cell 301, thereby improving the performance of the solar cell 301.

[0111] For example, 0 < L ≤ 0.6 mm, and L can be 0.1 mm, 0.11 mm, 0.13 mm, 0.15 mm, 0.17 mm, 0.19 mm, 0.2 mm, 0.21 mm, 0.23 mm, 0.25 mm, 0.27 mm, 0.29 mm, 0.3 mm, 0.31 mm, 0.33 mm, 0.35 mm, 0.37 mm, 0.39 mm, 0.4 mm, 0.41 mm, 0.43 mm, 0.45 mm, 0.47 mm, 0.49 mm, 0.5 mm, 0.51 mm, 0.53 mm, 0.55 mm, 0.57 mm, 0.59 mm, 0.6 mm, etc.

[0112] For example, 0.6mm≤L≤1.2mm, where L can be 0.6mm, 0.61mm, 0.63mm, 0.65mm, 0.67mm, 0.69mm, 0.7mm, 0.71mm, 0.73mm, 0.75mm, 0.77mm, 0.79mm, 0.8mm, 0.81mm, 0.83mm, 0.85mm, 0.87mm, 0.89mm, 0.9mm, 0.91mm, 0.93mm, 0.95mm, 0.97mm, 0.99mm, 1.0mm, 1.01mm, 1.03mm, 1.05mm, 1.07mm, 1.09mm, 1.1mm, 1.11mm, 1.13mm, 1.15mm, 1.17mm, 1.19mm, 1.2mm, etc.

[0113] Furthermore, the vertical distance between the first grid line 21 and the edge of the body 1 and the vertical distance between the second grid line 22 and the edge of the body 1 can be equal or unequal.

[0114] When the cell 301 is a TOPCon cell, the cell 301 includes a light-facing surface and a backlight surface that are disposed opposite to each other along its own thickness direction.

[0115] In some embodiments, the connecting grid line 6 is located on the light-facing side of the solar cell 301, and the connecting grid line 6 is not provided on the back-facing side of the solar cell 301.

[0116] In some embodiments, the connecting grid line 6 is located on the back surface of the battery cell 301, and the connecting grid line 6 is not provided on the light-facing surface of the battery cell 301.

[0117] In some embodiments, both the light-facing and back-facing surfaces of the solar cell 301 are provided with connecting grid lines 6.

[0118] The embodiments of this application do not impose special limitations on the placement of the connecting gate line 6.

[0119] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, The battery cell (301) includes: The body (1) includes a plurality of ends (11) in a plane perpendicular to the thickness direction of the body (1) along the circumference of the body (1). Edge grid line (2), the area between the edge grid line (2) and the edge of the body (1) is the outer area (5); A connecting grid line (6) is located in the outer region (5), one end of the connecting grid line (6) is connected to the edge of the body (1), and the other end of the connecting grid line (6) is connected to the edge grid line (2); The line connecting the endpoint of the edge grid line (2) and the adjacent end (11) is the vertex line (12) of the body (1). The connecting grid line (6) includes a plurality of first connecting lines (61). The first connecting lines (61) are parallel to the vertex line (12). The plurality of first connecting lines (61) are arranged at intervals along a first direction (X) and / or a second direction (Y). The first connecting line (61) includes a corner connecting line (611), one end of which is connected to the endpoint of the edge grid line (2), and the other end of which is connected to the end (11) of the body (1). The corner connecting line (611) coincides with the vertex connecting line (12). The connecting grid line (6) further includes a second connecting line (62), which is located between adjacent first connecting lines (61); The two ends of the second connecting line (62) are respectively connected to the edge grid line (2) and the edge of the body (1), and the two ends of the second connecting line (62) are respectively connected to the adjacent first connecting line (61).

2. The battery cell according to claim 1, characterized in that, The lengths of the first connecting line (61) and the second connecting line (62) are equal.

3. The battery cell according to claim 1, characterized in that, The edge grid line (2) includes a first grid line (21) extending along the first direction (X) and a second grid line (22) extending along the second direction (Y), the first grid line (21) and the second grid line (22) forming an inner region (4). The connecting grid line (6) is provided between the second grid line (22) and the edge of the body (1). The battery cell (301) further includes internal grid lines (3) extending along the first direction (X) and arranged along the second direction (Y), the internal grid lines (3) being located within the inner region (4); The internal grid line (3) intersects the second grid line (22) at a first intersection point (23), and a plurality of the first intersection points (23) are arranged along the second direction (Y); The first connecting line (61), the second connecting line (62) and the second gate line (22) intersect at the second intersection point (24), and a plurality of the second intersection points (24) are arranged along the second direction (Y); At least one of the first intersection points (23) coincides with the second intersection point (24).

4. The battery cell according to any one of claims 1 to 3, characterized in that, The outer region (5) includes a first region (51) and a second region (52) arranged along a first direction (X), and the connecting grid line (6) is provided in both the first region (51) and the second region (52).

5. The battery cell according to claim 4, characterized in that, The connecting grid line (6) in the first region (51) and the connecting grid line (6) in the second region (52) are symmetrically arranged, with the axis of symmetry parallel to the second direction (Y). Alternatively, the connecting grid lines (6) in the first region (51) and the connecting grid lines (6) in the second region (52) are arranged symmetrically.

6. The battery cell according to any one of claims 1 to 3, characterized in that, The edge grid line (2) includes a first grid line (21) extending along a first direction (X); A portion of the connecting grid line (6) is located between the first grid line (21) and the edge of the body (1).

7. The battery cell according to claim 6, characterized in that, In the second direction (Y), between the first gate line (21) and the edge of the body (1), the outer region (5) includes a clearance region (54) for placing solder strips (302). The avoidance area (54) is not provided with the connecting grid line (6).

8. The battery cell according to any one of claims 1 to 3, characterized in that, The vertical distance between the edge grid line (2) and the edge of the body (1) is L, where 0 < L ≤ 1.2 mm.

9. The battery cell according to any one of claims 1 to 3, characterized in that, The body (1) includes a light-facing surface and a back-light-facing surface arranged in its own thickness direction. The light-facing surface and the back-light-facing surface are provided with the edge grid line (2) and the internal grid line (3). The connecting grid line (6) is located on the light-facing surface and / or the back-facing surface of the body (1).

10. A photovoltaic module, characterized in that, The photovoltaic module includes a cover plate (10), an encapsulation layer (20) and a battery layer (30), wherein the encapsulation layer (20) is located between the cover plate (10) and the battery layer (30); The battery layer (30) includes a plurality of battery cells (301) according to any one of claims 1 to 9, and the battery layer (30) further includes a solder ribbon (302) electrically connected to the internal grid lines (3) of the battery cells (301), and adjacent battery cells (301) are electrically connected to each other through the solder ribbon (302).

Images