Solar cell, printing screen plate and photovoltaic module

Abstract

The utility model relates to the technical field of solar cells, in particular to a solar cell, a printing screen and a photovoltaic module. The solar cell comprises a cell body, a plurality of first grid lines and a plurality of second grid lines. The battery body is provided with two battery edges which are oppositely arranged; in the opposite directions of the two battery edges, the plurality of first grid lines are arranged on the surface of the battery body at intervals. The plurality of second grid lines are arranged on the surface of the battery body, and each first grid line intersects with the plurality of second grid lines. Wherein the plurality of first grid lines comprise the outermost grid line, and the outermost grid line is the first grid line closest to the edge of the battery. And in the length direction of the second grid line, a part of the outermost grid line is provided with a lap joint part which is formed by recessing towards the center close to the battery body. On the outermost grid line, each lap joint portion intersects with each second grid line. In the manufacturing process of the solar cell, the intersection of the outermost grid line and the second grid line can be considered, and the abnormities of grid breakage, virtual printing and the like are not easy to occur.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a solar cell, a printing screen, and a photovoltaic module. Background Art

[0002] The gridline electrodes of solar cells include a first gridline and a second gridline that intersects the first gridline. However, the intersection of the first and second gridlines at the edge of the solar cell is prone to grid breakage during the printing process. This occurs when the first and second gridlines are disconnected after printing, without forming an overlap. This can affect the performance of the solar cell. Utility Model Content

[0003] The embodiments of the present application disclose a solar cell, a printing screen, and a photovoltaic module, which can take into account the intersection of the first grid line and the second grid line while being less likely to have abnormalities such as broken grid and virtual printing. At the same time, the printing screen for printing the solar cell has a longer service life and the manufacturing cost of the solar cell is reduced.

[0004] To achieve the above objectives, in a first aspect, embodiments of the present application disclose a solar cell, comprising:

[0005] A battery body, the battery body having two battery edges arranged opposite to each other;

[0006] a plurality of first grid lines, which are arranged at intervals on the surface of the battery body in the opposite directions of the two battery edges; and

[0007] a plurality of second grid lines, wherein the plurality of second grid lines are arranged on the surface of the battery body, and each of the first grid lines intersects with the plurality of second grid lines;

[0008] Among them, several of the first grid lines include an outermost grid line, which is the first grid line closest to the edge of the battery; in the length direction of the second grid lines, a part of at least one of the outermost grid lines has an overlapping portion formed inwardly toward the center of the battery body; on the outermost grid lines, each of the overlapping portions intersects with each of the second grid lines respectively.

[0009] In a possible implementation of the first aspect, the overlapping portion is rectangular, trapezoidal, or arc-shaped.

[0010] In a possible implementation of the first aspect, the outermost grid line further includes a plurality of grid line main body segments, and the grid line main body segments and the overlapping portions are alternately arranged;

[0011] Each of the overlapping portions includes an overlapping section and two oppositely arranged extension sections, the two extension sections respectively connecting the two grid line main sections on both sides of the overlapping portion, and each of the extension sections extends along a direction close to the center of the battery body, the overlapping section and the grid line main section are arranged in the same direction, the two ends of the overlapping section are respectively connected to one end of the two extension sections away from the grid line main section, and the second grid line intersects with the overlapping section.

[0012] In a possible implementation of the first aspect, the shortest distance between the edge of the battery and the outermost grid line is less than or equal to the shortest distance between the edge of the battery and the second grid line.

[0013] In a possible implementation of the first aspect, the shortest distance between the edge of the battery and the second grid line is 0.5 cm to 0.6 cm.

[0014] In a possible implementation of the first aspect, the first gate line is a bus gate line, the second gate line is a current collecting gate line, and there are multiple bus gate lines and multiple current collecting gate lines. In relative directions of two battery edges, the multiple bus gate lines are arranged at intervals, each bus gate line intersects with the multiple current collecting gate lines, and the current collecting gate lines on two adjacent bus gate lines are arranged in an interdigitated manner.

[0015] And / or, the battery body includes a silicon substrate, a doping layer, and a functional film; the doping layer is disposed on a surface of the silicon substrate; the functional film is disposed on a side of the doping layer facing away from the silicon substrate, and the first gate line and / or the second gate line passes through the functional film and makes ohmic contact with the doping layer;

[0016] And / or, the first gate line and the second gate line intersect vertically;

[0017] And / or, the battery body is a sliced ​​battery;

[0018] And / or, the cell body is a back-contact solar cell body.

[0019] In a second aspect, an embodiment of the present application discloses a printing screen for printing the solar cell according to the first aspect, wherein the printing screen comprises:

[0020] A printing screen having a printing pattern area, the printing pattern area having two printing edges arranged opposite to each other, and a plurality of grid line printing holes provided on the printing pattern area;

[0021] In the relative directions of the two printing edges, a plurality of the grid line printing holes are arranged at intervals on the printing graphic area, and the plurality of the grid line printing holes include the outermost printing hole, and the outermost printing hole is the grid line printing hole closest to the printing edge. At least one of the outermost printing holes is partially concave inward along the direction close to the center of the printing screen to form a plurality of overlapping printing holes.

[0022] In a possible implementation of the second aspect, the outermost printing holes further include grid line body printing holes, and the grid line body printing holes and the overlapping portion printing holes are alternately arranged;

[0023] Each of the overlapping portion printing holes includes an overlapping section printing hole and two oppositely arranged extension section printing holes, the two extension section printing holes are respectively connected to the two grid line main body printing holes on both sides of the overlapping portion printing hole, and each of the extension section printing holes extends in a direction close to the center of the printing screen, and the two ends of the overlapping section printing hole are respectively connected to one end of the two extension section printing holes away from the grid line main body printing hole.

[0024] In a possible implementation of the second aspect, the printing screen further includes:

[0025] A flexible protection zone is superimposed on the surface of the printing screen and is arranged around the periphery of the printed graphic area. The flexible protection zone is configured to contact the battery body.

[0026] In a possible implementation of the second aspect, the flexible protection zone is an annular PI tape;

[0027] and / or, the thickness of the flexible protection zone is 8 μm to 10 μm;

[0028] And or, the flexible protection zone is configured to have an overlapping area with the solar cell with a width of 0.1 cm to 0.2 cm.

[0029] In a possible implementation of the second aspect, the printing screen further includes:

[0030] An elastic composite mesh, wherein the printed mesh further comprises a bonding area, the bonding area being arranged around the printed graphic area, the elastic composite mesh being annular, and the bonding area being superimposed on an inner ring of the elastic composite mesh; and

[0031] A screen frame is provided, wherein the outer ring of the elastic composite screen is connected to the screen frame.

[0032] In a possible implementation of the second aspect, the printing mesh is a steel mesh, and the thickness of the steel mesh is 10 μm to 20 μm;

[0033] And / or, the elastic composite mesh is a polyester composite mesh.

[0034] In a third aspect, an embodiment of the present application discloses a photovoltaic module comprising a plurality of solar cells connected in series and / or in parallel, at least one of the solar cells being the solar cell described in the first aspect, or at least one of the solar cells being the solar cell obtained by screen printing as described in the second aspect.

[0035] Compared with the prior art, the beneficial effects of the present application are as follows: the outermost grid line of the solar cell has a portion of an overlapped portion formed inwardly toward the center of the battery body, and on the outermost grid line, each overlapped portion intersects with each second grid line respectively, thereby reducing the phenomenon of broken grids. Furthermore, the overlapped portion makes it unnecessary for the second grid line to intersect with the outermost grid line by protruding the outermost grid line, and the second grid line can be farther away from the edge of the battery, which can provide a larger adjustment space for the flexible protection zone of the printing screen during the printing process of the second grid line. The flexible protection zone can be adjusted to a suitable position to contact the battery body to protect the printing screen, thereby extending the service life of the printing screen. In addition, the penetration hole used for printing the second grid line can maintain an appropriate distance from the flexible protection zone, reducing the probability of printing abnormalities of the second grid line.

[0036] In summary, the solar cell provides an overlapping portion on the outermost grid line, and the second grid line intersects with the overlapping portion to reduce the grid breakage phenomenon. At the same time, the second grid line can be farther away from the edge of the battery, and printing anomalies are reduced when printing the second grid line. The service life of the printing screen is extended, thereby reducing the manufacturing cost of the solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 A schematic structural diagram of a solar cell disclosed in an embodiment of the present application;

[0039] Figure 2 This is another structural schematic diagram of a solar cell disclosed in an embodiment of the present application;

[0040] Figure 3 A schematic structural diagram of a printing screen disclosed in an embodiment of the present application;

[0041] Figure 4 This is a schematic diagram of printing of a printing screen disclosed in an embodiment of the present application.

[0042] Description of reference numerals:

[0043] 100. Solar cell; 110. Cell body; 111. Cell edge; 112. Silicon substrate; 113. Doping layer; 114. Functional film; 120. First grid line; 120a. Outermost grid line; 121. Overlapping portion; 1211. Overlapping section; 1212. Extended section; 122. Grid line main section; 130. Second grid line; 131. Protruding section; 200. Printing screen; 210. Printing mesh; 211. Printing graphic area; 2111. Printing edge; 212. Bonding area; 220. Grid line printing hole; 220a. Outermost printing hole; 221. Overlapping portion printing hole; 2211. Overlapping section printing hole; 2212. Extended section printing hole; 222. Grid line main section printing hole; 230. Flexible protection zone; 240. Elastic composite mesh; 250. Screen frame; 260. Penetration hole; 300. Scraper. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0045] In this application, the terms "inside" and "outside" and the like indicate positions or locations based on those shown in the accompanying drawings. These terms are primarily intended to better describe this application and its embodiments and are not intended to limit the devices, elements, or components indicated to specific positions, or to their construction or operation in a specific position.

[0046] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to express a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0047] Furthermore, the terms "disposed," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; or internal communication between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0048] Furthermore, the terms "first," "second," etc., are primarily used to distinguish between different devices, elements, or components (which may or may not be of the same type and configuration), and are not intended to indicate or imply the relative importance or quantity of the devices, elements, or components indicated. Unless otherwise specified, "plurality" means two or more.

[0049] The technical solution of the present utility model will be described below with reference to the embodiments and drawings.

[0050] First, see Figure 1 The embodiment of the present application discloses a solar cell 100, comprising a cell body 110, a plurality of first grid lines 120, and a plurality of second grid lines 130. The cell body 110 has two cell edges 111 disposed opposite to each other. The relative directions of the two cell edges 111 are Figure 1 In the Y0-Y1 direction shown in FIG, a plurality of first grid lines 120 are spaced apart on the surface of the battery body 110 in the opposite direction of the two battery edges 111. A plurality of second grid lines 130 are disposed on the surface of the battery body 110, and each first grid line 120 intersects with a plurality of second grid lines 130.

[0051] The plurality of first grid lines 120 include an outermost grid line 120a, which is the first grid line 120 closest to the battery edge 111. The length direction of the second grid line 130 is Figure 1 In the Y0-Y1 direction shown in FIG, along the length direction of second gridlines 130, a portion of at least one outermost gridline 120a is concave near the center of battery body 110 to form an overlapping portion 121. The center of battery body 110 is the center between the two outermost gridlines 120a. On the outermost gridlines 120a, each overlapping portion 121 intersects with each second gridline 130.

[0052] It should be noted that the solar cell 100 has two outermost grid lines 120 a , and the overlapping portion 121 may be provided on only one of the outermost grid lines 120 a , or may be provided on both outermost grid lines 120 a .

[0053] The outermost grid line 120a of the solar cell 100 has a portion of a lap joint 121 that is concave toward the center of the battery body 110. On the outermost grid line 120a, each lap joint 121 intersects with each second grid line 130, thereby reducing the phenomenon of broken grids. Furthermore, the lap joint 121 eliminates the need for the second grid line 130 to intersect with the outermost grid line 120a by protruding from the outermost grid line 120a. The second grid line 130 can be farther away from the battery edge 111, providing greater adjustment space for the flexible protection zone 230 of the printing screen 200 during the printing process of the second grid line 130. The flexible protection zone 230 can be adjusted to a suitable position to contact the battery body 110 to protect the printing screen 200, thereby extending the service life of the printing screen 200. In addition, the penetration hole 260 used for printing the second grid line 130 can maintain an appropriate distance from the flexible protection zone 230, reducing the probability of printing abnormalities of the second grid line 130.

[0054] In summary, the solar cell 100 reduces the grid break phenomenon by setting the overlapping portion 121 on the outermost grid line 120a, and the second grid line 130 intersects with the overlapping portion 121. At the same time, the second grid line 130 can be farther away from the cell edge 111, and printing anomalies are reduced when printing the second grid line 130. The service life of the printing screen 200 is extended, thereby reducing the manufacturing cost of the solar cell 100.

[0055] For example, see Figure 1 , the overlapping portion 121 has a rectangular shape. As another example, the overlapping portion 121 may also have a trapezoidal or arcuate shape. It should be noted that when the overlapping portion 121 is a continuous line structure, the overlapping portion 121 having an arcuate shape means that the overlapping portion 121 has an arcuate line structure, and the overlapping portion 121 having a rectangular or trapezoidal shape means that the overlapping portion 121 is arranged along three connected sides of the rectangle or trapezoid.

[0056] The overlapping portion 121 of the above-mentioned pattern is relatively easy to process the overlapping portion printing hole 221 of the corresponding shape on the printing screen 210, and the printing effect is better.

[0057] Alternatively, see Figure 1 The outermost gate line 120a further includes a plurality of gate line main sections 122 , which are alternately arranged with the overlapping portions 121 , and a plurality of second gate lines 130 spaced apart are arranged on the outermost gate line 120a and intersect with the plurality of overlapping portions 121 respectively.

[0058] Each overlapping portion 121 comprises an overlapping section 1211 and two relatively arranged extensions 1212, two extensions 1212 connect two grid line main sections 122 on both sides of the overlapping section 121 respectively, and each extension 1212 extends along the center near the battery body 110, the overlapping section 1211 and the grid line main section 122 are arranged in the same direction, the two ends of the overlapping section 1211 are respectively connected to one end away from the grid line main section 122 with the two extensions 1212, and the second grid line 130 intersects with the overlapping section 1211. The overlapping section 121 of the above-mentioned graphic structure is easier to print, and the printing quality is high. Utilize this overlapping section 1211 to intersect and overlap with the second grid line 130, due to the certain length of the overlapping section 1211, the second grid line 130 can intersect with the overlapping section 1211 at any point on the length direction of the overlapping section 1211, and the alignment accuracy requirement for the second grid line 130 is reduced.

[0059] For example, see Figure 1 , the shortest distance D5 between the battery edge 111 and the outermost gridline 120a is less than the shortest distance D4 between the battery edge 111 and the second gridline 130. As another example, the shortest distance between the battery edge 111 and the outermost gridline 120a is equal to the shortest distance between the battery edge 111 and the second gridline 130. That is, the second gridline 130 preferably no longer protrudes beyond the outermost gridline 120a, so that the second gridline 130 is farther away from the battery edge 111, the printing quality of the second gridline 130 is better, and the service life of the printing screen 200 is extended.

[0060] Optionally, the shortest distance D4 between the battery edge 111 and the second grid line 130 is 0.5 cm to 0.6 cm, including any point value within this distance range, for example, 0.5 cm, 0.55 cm or 0.6 cm. It can be understood that the above-mentioned second grid lines 130 refer to the second grid lines 130 that intersect with the overlapping portion 121. These second grid lines 130 are closest to the battery edge 111, and the distance between these second grid lines 130 and the battery edge 111 is the shortest distance between all second grid lines 130 and the battery edge 111. The above distance indicates that the second grid lines 130 that intersect with the overlapping portion 121 are far enough away from the battery edge 111, and the printing quality is better.

[0061] For example, see Figure 1 Each first grid line 120 is a busbar, and each second grid line 130 is a current collecting grid line. There are multiple busbars and current collecting grid lines. In the relative directions of the two battery edges 111, multiple busbars are arranged at intervals. Each busbar intersects with multiple current collecting grid lines, and the current collecting grid lines on two adjacent busbars are arranged in a cross-digital arrangement. The function of the current collecting grid line is to collect current from the silicon substrate. The function of the busbar is to collect the current collected by the current collecting grid line and output it through the welding strip.

[0062] As another example, when the solar cell 100 is a busbar-less solar cell 100 , the first grid lines 120 and the second grid lines 130 are both thin grid lines.

[0063] Alternatively, as Figure 1 As shown, the first gate line 120 and the second gate line 130 intersect vertically, and the length direction of the first gate line 120 is as shown in FIG. Figure 1 The X0 - X1 direction shown in FIG is perpendicular to the length direction (Y0 - Y1 direction) of the second gate line 130 to better transmit current.

[0064] In some embodiments, see Figure 2 , the battery body 110 includes a silicon substrate 112, a doping layer 113 and a functional film 114. The doping layer 113 is arranged on the surface of the silicon substrate 112. The functional film 114 is arranged on the side of the doping layer 113 facing away from the silicon substrate 112, and the first gate line 120 and / or the second gate line 130 pass through the functional film 114 and make ohmic contact with the doping layer 113. Optionally, the functional film 114 can be an anti-reflection film and / or a passivation film. The doping layer 113 can be a doped amorphous silicon layer, a doped polycrystalline silicon layer or a diffusion layer formed by diffusion on the surface of the silicon substrate 112. The conductivity type of the doping layer 113 can be the same as or opposite to that of the silicon substrate 112. Exemplarily, in Figure 2 In the embodiment, the cell body 110 is a back-contact solar cell body, that is, a back-contact solar cell without electrodes. As another example, the solar cell may also be a passivated contact solar cell, a heterojunction solar cell, or other types of solar cells.

[0065] Optionally, the cell body 110 is a sliced ​​cell. Exemplarily, the sliced ​​cell is a half-cell. As other examples, the sliced ​​cell can be a third-cell or a quarter-cell. Sliced ​​cells can reduce module power loss. The solar cell 100 provided in this embodiment of the application addresses the problem of printing anomalies often associated with sliced ​​cells, and also extends the life of the printing screen 200 used to print the sliced ​​cells, reducing the production cost of sliced ​​cells.

[0066] Second, see Figure 3 and Figure 4 The present invention discloses a printing screen 200 for printing the solar cell described in the first aspect. The printing screen 200 includes a printing screen 210 having a printing pattern area 211. The printing pattern area 211 has two oppositely disposed printing edges 2111. The printing pattern area 211 is provided with a plurality of grid line printing holes 220.

[0067] The printing screen 210 is configured to move relative to the scraper 300 in opposite directions of the two printing edges 2111. In other words, the starting position and the ending position of the scraper 300 are respectively at the two printing edges 2111.

[0068] In the relative directions of the two printing edges 2111, a plurality of grid line printing holes 220 are spaced apart on the printing graphic area 211, and the plurality of grid line printing holes 220 include the outermost printing hole 220a, which is the grid line printing hole 220 closest to the printing edge 2111. A portion of at least one outermost printing hole 220a is concave inwardly in a direction close to the center of the printing screen 210 to form a plurality of overlapping printing holes 221.

[0069] For example, Figure 3 In the direction close to the center of the printing screen 210, Figure 3 In the Y1 direction and the Y2 direction, a portion of one of the outermost printing holes 220a is concave inward along the Y1 direction to form a plurality of overlapping printing holes 221; and / or a portion of the other outermost printing hole 220a is concave inward along the Y2 direction to form a plurality of overlapping printing holes 221.

[0070] Please combine Figure 1 、 Figure 3 and Figure 4 The two printing edges 2111 of the printing screen 200 are configured to face the two battery edges 111 during printing. The printed pattern area 211 is configured to face the surface to be printed of the battery body 110. The slurry is applied to the side of the printed pattern area 211 facing away from the battery body 110. When the scraper 300 and the printing screen 210 move relative to each other, the scraper 300 applies external pressure to allow the slurry to pass through the grid line printing holes 220 and be applied to the surface to be printed, forming the first grid line 120. In other words, the grid line printing holes 220 are configured to print the first grid line 120, the outermost printing holes 220a are configured to print the outermost grid line 120a, and the overlapping portion printing holes 221 are configured to print the overlapping portion 121.

[0071] The overlapped portion 121 obtained by printing the overlapped portion printing hole 221 of the printing screen 200 intersects with the second grid line 130, thereby reducing the phenomenon of broken grid. Furthermore, the overlapped portion 121 makes it unnecessary for the second grid line 130 to intersect with the outermost grid line 120a by protruding the outermost grid line 120a. The second grid line 130 can be farther away from the battery edge 111, and the flexible protection zone of the printing screen can be provided with a larger adjustment space during the printing process of the second grid line 130. The flexible protection zone can be adjusted to a suitable position to contact the battery body to protect the printing screen, thereby extending the service life of the printing screen. In addition, the penetration hole used to print the second grid line 130 can maintain an appropriate distance from the flexible protection zone, reducing the probability of printing abnormalities of the second grid line 130.

[0072] In summary, the printing screen 200 sets the overlapping portion printing hole 221 at the outermost printing hole 220a, and the printed overlapping portion 121 intersects with the second grid line 130 to reduce the grid break phenomenon. At the same time, the second grid line 130 can be farther away from the battery edge 111, and printing anomalies are reduced when printing the second grid line 130. The service life of the printing screen is extended, thereby reducing the manufacturing cost of the solar cell 100.

[0073] In some embodiments, reference Figure 3 The outermost printing holes 220 a further include gate line main body printing holes 222 , and the gate line main body printing holes 222 and the overlapping portion printing holes 221 are alternately arranged.

[0074] Each overlapping portion printing hole 221 includes an overlapping section printing hole 2211 and two oppositely arranged extension section printing holes 2212. The two extension section printing holes 2212 are respectively connected to the two grid line main body printing holes 222 on both sides of the overlapping portion printing hole 221, and each extension section printing hole 2212 extends in a direction close to the center of the printing screen 210. The two ends of the overlapping section printing hole 2211 are respectively connected to the ends of the two extension section printing holes 2212 away from the grid line main body printing hole 222.

[0075] Please refer to Figure 1 Combined with Figure 3 The grid line main body printing hole 222 is configured to print the grid line main body segment 122, the overlapping segment printing hole 2211 is configured to print the overlapping segment 1211, and the extension segment printing hole 2212 is configured to print the extension segment 1212. The overlapping segment 1211 printed by the overlapping segment printing hole 2211 intersects and overlaps with the second grid line 130. Since the overlapping segment 1211 has a certain length, the second grid line 130 can intersect with the overlapping segment 1211 at any point along the length direction of the overlapping segment 1211, reducing the alignment accuracy requirements for the second grid line 130.

[0076] In some embodiments, reference Figure 4 The printing screen 200 further includes a flexible protection zone 230, which is superimposed on the surface of the printing screen 210 and surrounds the printed pattern area 211. The flexible protection zone 230 is configured to contact the battery body 110 to protect the printing screen 200 and reduce damage to the printing screen 200 caused by the battery body 110.

[0077] Preferably, the flexible protection zone 230 is a ring-shaped PI (polyimide) tape. Exemplarily, the ring-shaped PI tape conforms to the contour of the printed pattern area 211. During the printing process, the printed pattern area 211 corresponds to the printed surface of the solar cell 100, and the ring-shaped PI tape contacts the entire edge of the cell body 110, providing better protection.

[0078] Preferably, the thickness of the flexible protection zone 230 is between 8 μm and 10 μm, including any value within this thickness range, such as 8 μm, 9 μm, or 10 μm. The flexible protection zone 230 of this thickness provides good protection and, when in contact with the battery body 110, provides less elevation of the printed screen 210, allowing the printed pattern area 211 to better fit the battery body 110.

[0079] Preferably, refer to Figure 4 The flexible protection zone 230 is configured to have a width W of 0.1 cm to 0.2 cm in the overlapping area with the solar cell 100, including any value within the width range, such as 0.1 cm, 0.15 cm or 0.2 cm, to effectively reduce the damage of the battery body 110 to the printing screen 200.

[0080] In some embodiments, reference Figure 3 and Figure 4 The printing screen 200 also includes an elastic composite mesh 240 and a screen frame 250. The printing screen 210 further includes a bonding area 212, which is arranged around the printed pattern area 211. The elastic composite mesh 240 is annular, and the bonding area 212 is superimposed on the inner ring of the elastic composite mesh 240. The elastic composite mesh 240 is used to increase the tension and elasticity of the printing screen 200. At the bonding area 212, the elastic composite mesh 240 and the printing screen 210 are stacked to enhance the bonding strength and improve the overall structural strength of the printing screen 200. The outer ring of the elastic composite mesh 240 is connected to the screen frame 250. The screen frame 250 provides support.

[0081] Preferably, the elastic composite mesh 240 is a polyester composite mesh, which has better elasticity and tension and a longer service life.

[0082] Preferably, the printing screen 210 is a steel mesh having a thickness of 10 μm to 20 μm, including 10 μm, 15 μm, or 20 μm, which allows for both low slurry consumption and a long service life. More specifically, the steel mesh is coated with a glue layer, and the grid line printing holes 220 may be holes formed by engraving the glue layer.

[0083] In a third aspect, an embodiment of the present application discloses a photovoltaic module comprising a plurality of solar cells connected in series and / or in parallel, at least one of the solar cells being the solar cell described in the first aspect, or at least one of the solar cells being the solar cell obtained by screen printing as described in the second aspect.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A solar cell, characterized in that: include: A battery body, the battery body having two battery edges arranged opposite to each other; a plurality of first grid lines, which are arranged at intervals on the surface of the battery body in the opposite directions of the two battery edges; and a plurality of second grid lines, wherein the plurality of second grid lines are arranged on the surface of the battery body, and each of the first grid lines intersects with the plurality of second grid lines; Among them, several of the first grid lines include an outermost grid line, which is the first grid line closest to the edge of the battery; in the length direction of the second grid lines, a part of at least one of the outermost grid lines has an overlapping portion formed inwardly toward the center of the battery body; on the outermost grid lines, each of the overlapping portions intersects with each of the second grid lines respectively.

2. The solar cell according to claim 1, characterized in that The overlapping portion is in the shape of a rectangle, a trapezoid or an arc.

3. The solar cell according to claim 2, characterized in that The outermost grid line further includes a plurality of grid line main body segments, and the grid line main body segments and the overlapping portions are alternately arranged; Each of the overlapping portions includes an overlapping section and two oppositely arranged extension sections, the two extension sections respectively connecting the two grid line main sections on both sides of the overlapping portion, and each of the extension sections extends along a direction close to the center of the battery body, the overlapping section and the grid line main section are arranged in the same direction, the two ends of the overlapping section are respectively connected to one end of the two extension sections away from the grid line main section, and the second grid line intersects with the overlapping section.

4. The solar cell according to claim 1, wherein The shortest distance between the edge of the battery and the outermost grid line is less than or equal to the shortest distance between the edge of the battery and the second grid line.

5. The solar cell according to claim 4, characterized in that The shortest distance between the edge of the battery and the second grid line is 0.5 cm to 0.6 cm.

6. The solar cell according to any one of claims 1 to 5, characterized in that The first grid line is a bus grid line, and the second grid line is a current collecting grid line. There are multiple bus grid lines and multiple current collecting grid lines. In the relative directions of the two battery edges, the multiple bus grid lines are arranged at intervals. Each bus grid line intersects with the multiple current collecting grid lines, and the current collecting grid lines on two adjacent bus grid lines are arranged in an interdigitated manner. And / or, the first gate line and the second gate line intersect vertically; And / or, the battery body includes a silicon substrate, a doping layer, and a functional film; the doping layer is disposed on a surface of the silicon substrate; the functional film is disposed on a side of the doping layer facing away from the silicon substrate, and the first gate line and / or the second gate line passes through the functional film and makes ohmic contact with the doping layer; And / or, the battery body is a sliced ​​battery; And / or, the cell body is a back-contact solar cell body.

7. A printing screen for printing the solar cell according to any one of claims 1 to 6, characterized in that: The printing screen comprises: A printing screen, wherein the printing screen has a printing pattern area, the printing pattern area has two printing edges arranged opposite to each other, and the printing pattern area is provided with a plurality of grid line printing holes; In the relative directions of the two printing edges, a plurality of the grid line printing holes are arranged at intervals on the printing graphic area, and the plurality of the grid line printing holes include the outermost printing hole, and the outermost printing hole is the grid line printing hole closest to the printing edge. At least one of the outermost printing holes is partially concave inward along the direction close to the center of the printing screen to form a plurality of overlapping printing holes.

8. The printing screen according to claim 7, wherein: The outermost printing holes further include grid line main body printing holes, and the grid line main body printing holes and the overlapping portion printing holes are alternately arranged; Each of the overlapping portion printing holes includes an overlapping section printing hole and two oppositely arranged extension section printing holes, the two extension section printing holes are respectively connected to the two grid line main body printing holes on both sides of the overlapping portion printing hole, and each of the extension section printing holes extends in a direction close to the center of the printing screen, and the two ends of the overlapping section printing hole are respectively connected to one end of the two extension section printing holes away from the grid line main body printing hole.

9. The printing screen according to claim 7, wherein: The printing screen also includes: A flexible protection zone is superimposed on the surface of the printing screen and is arranged around the periphery of the printed graphic area. The flexible protection zone is configured to contact the battery body.

10. The printing screen according to claim 9, characterized in that The flexible protection zone is a ring-shaped PI tape; and / or, the thickness of the flexible protection zone is 8 μm to 10 μm; And or, the flexible protection zone is configured to have an overlapping area with the solar cell with a width of 0.1 cm to 0.2 cm.

11. The printing screen according to any one of claims 7 to 10, characterized in that The printing screen also includes: An elastic composite mesh, wherein the printed mesh further comprises a bonding area, the bonding area being arranged around the printed graphic area, the elastic composite mesh being annular, and the bonding area being superimposed on an inner ring of the elastic composite mesh; and A screen frame is provided, wherein the outer ring of the elastic composite screen is connected to the screen frame.

12. The printing screen according to claim 11, wherein: The printing mesh is a steel mesh, and the thickness of the steel mesh is 10 μm to 20 μm; And / or, the elastic composite mesh is a polyester composite mesh.

13. A photovoltaic module, characterized in that: The invention comprises a plurality of solar cells connected in series and / or in parallel, at least one of the solar cells is the solar cell according to any one of claims 1 to 6, or at least one of the solar cells is the solar cell obtained by screen printing according to any one of claims 7 to 12.

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