Solar cell, solar cell module and photovoltaic system

Abstract

The utility model relates to the technical field of solar cells, and discloses a solar cell, a solar cell module and a photovoltaic system, the back of the solar cell is provided with a first grid line, a second grid line, a first edge grid line and a second edge grid line, and the first edge grid line and the second edge grid line are arranged along a first direction. A first Pad point and a second Pad point are arranged at two end parts of the solar cell, the first Pad point is connected with the first grid line, the first Pad point is connected with the first edge grid line, the second Pad point is connected with the second grid line, and the second Pad point is connected with the second edge grid line. According to the invention, the area of the PN junction formed on the solar cell is increased, the power of the solar cell is improved, and the reliability of the solar cell is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of solar cells, in particular to a solar cell, a solar cell assembly and a photovoltaic system. Background Art

[0002] Solar cells are semiconductor devices that convert light energy into electrical energy. Low production costs and high energy conversion efficiency have always been the goals of the solar cell industry. Factors that influence high energy conversion efficiency include not only the light-receiving area of ​​the solar cell but also the area of ​​the PN junction on the cell. The PN junction is the core component of a solar cell and is composed of P-type and N-type semiconductor materials. When light strikes the PN junction, electron-hole pairs are generated on either side. These electrons are separated by the built-in electric field, generating a photocurrent.

[0003] In the prior art, such as Figure 1 As shown, the solar cell is provided with a first edge grid line and a second edge flash, and the end of the solar cell is provided with a third pad point and a fourth pad point arranged alternately along the first direction and connected to the grid line of the same polarity, and the connecting line of the third pad point and the connecting line of the fourth pad point at both ends are further provided with a first pad point and a second pad point uniformly distributed along the second direction. The arrangement of the first pad point and the second pad point results in a certain distance between them and the edge grid line, and there is no grid line with different polarity within this range, as shown in FIG. Figure 2 As shown, the effective area for forming the PN junction within the range is small, resulting in a waste of the light-emitting area of ​​the solar cell, thereby hindering the improvement of the light-emitting efficiency of the solar cell. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a solar cell, a solar cell module and a photovoltaic system, which can reduce the area waste on the solar cell, increase the area formed by the PN junction on the solar cell, and improve the power and reliability of the solar cell.

[0005] In order to solve the above technical problems, the first aspect of the present invention provides a solar cell, wherein a first grid line and a second grid line are provided on the back side of the solar cell, wherein the first grid line and the second grid line are parallel to each other and alternately arranged along a first direction;

[0006] Along the first direction, both side edges of the back side of the solar cell are provided with a first edge grid line and a second edge grid line extending along the second direction, wherein the first edge grid line is connected to the first grid line, and the second edge grid line is connected to the second grid line;

[0007] In the first direction, two ends of the solar cell piece are provided with a first Pad point and a second Pad point, the first Pad point is connected with the first grid line, and the first Pad point is connected with the first edge grid line, the second Pad point is connected with the second grid line, and the second Pad point is connected with the second edge grid line.

[0008] As an improvement of the above scheme, at least one end point of the first Pad point is connected with the first edge grid line.

[0009] At least one end point of the second Pad point is connected with the second edge grid line.

[0010] As an improvement of the above scheme, the first Pad point includes a first side edge arranged in the second direction, and the first Pad point is connected with the first edge grid line through the first side edge.

[0011] The second Pad point includes a first side edge arranged in the second direction, and the second Pad point is connected with the second edge grid line through the first side edge.

[0012] As an improvement of the above scheme, the first Pad point is connected with 1-5 first grid lines.

[0013] The second Pad point is connected with 1-5 second grid lines.

[0014] As an improvement of the above scheme, the first Pad point is connected with 2-5 first grid lines.

[0015] The second Pad point is connected with 2-5 second grid lines.

[0016] As an improvement of the above scheme, in the second direction, two ends of the first Pad point are respectively connected with the first grid line, and no second grid line is arranged between the two first grid lines.

[0017] And / or, two ends of the second Pad point are respectively connected with the second grid line, and no first grid line is arranged between the two second grid lines.

[0018] As an improvement of the above scheme, the shape of the first Pad point is one of triangle, rectangle, square, L type, trapezoid, circle, irregular pattern.

[0019] The shape of the second Pad point is one of triangle, rectangle, square, L type, trapezoid, circle, irregular pattern.

[0020] As an improvement of the above scheme, the area of the first Pad point is 0.6mm 2 -4mm2 ;

[0021] The area of the second Pad point is 0.6mm 2 ~4mm 2 .

[0022] As an improvement of the above scheme, the width of the first Pad point along the first direction is L1, and the distance between the first Pad point and the edge of the solar cell piece is L2, satisfying L1=(0.15~0.85)L2;

[0023] The width of the second Pad point along the first direction is L3, and the distance between the second Pad point and the edge of the solar cell piece is L4, satisfying L3=(0.15~0.85)L4.

[0024] As an improvement of the above scheme, the width L1 of the first Pad point along the first direction is 0.9mm~2mm;

[0025] The width L3 of the second Pad point along the first direction is 0.9mm~2mm.

[0026] As an improvement of the above scheme, the height H1 of the first Pad point along the second direction is 0.8mm~3mm;

[0027] The height H2 of the second Pad point along the second direction is 0.8mm~3mm.

[0028] As an improvement of the above scheme, the width L5 of the first edge grid line along the first direction is 30μm~400μm;

[0029] The width L6 of the second edge grid line along the first direction is 30μm~400μm.

[0030] As an improvement of the above scheme, a solder strip is arranged on the solar cell piece, and the solder strip connects adjacent first Pad points along the second direction;

[0031] And / or, a solder strip is arranged on the solar cell piece, and the solder strip connects adjacent second Pad points along the second direction.

[0032] As an improvement of the above scheme, the solar cell piece comprises a first region and a second region;

[0033] Along the second direction, both ends of the first region and the second region are provided with third Pad points and fourth Pad points arranged alternately along the first direction, the third Pad points are connected with the first grid lines, and the fourth Pad points are connected with the second grid lines.

[0034] As an improvement of the above-mentioned solution, the first edge busbar and / or the second busbar extends uninterruptedly along the second direction from one end of the first area to the other end of the first area and is connected with all the first busbars or the second busbars.

[0035] The first edge busbar and / or the second busbar extends uninterruptedly along the second direction from one end of the second area to the other end of the second area and is connected with all the first busbars or the second busbars.

[0036] As an improvement of the above-mentioned solution, the two ends of the first busbar are misaligned with the two ends of the second busbar, one end of the first busbar has a protruding end relative to one end of the second busbar, and the other end of the first busbar has a shortened end relative to the other end of the second busbar.

[0037] The first edge busbar is connected with the protruding end of the first busbar, and the second edge busbar is connected with the protruding end of the second busbar.

[0038] As an improvement of the above-mentioned solution, the first edge busbar, the second edge busbar, the first busbar and the second busbar are made of the same material.

[0039] The first Pad point, the second Pad point, the third Pad point and the fourth Pad point are made of the same material.

[0040] The utility model discloses a second aspect further provides a solar cell module, including the solar cell piece of the utility model discloses.

[0041] The utility model discloses a third aspect further provides a photovoltaic system, including the solar cell module.

[0042] Implement the utility model, has following beneficial effect:

[0043] In the utility model, by the first Pad point and the second Pad point are respectively close to the first edge busbar and the second edge busbar from the inside position of solar cell piece, and are connected with the first edge busbar and the second edge busbar respectively, shorten the distance between Pad point and edge busbar, make more first busbar and second busbar correspond, and then increase the area of PN junction formed on solar cell piece, be favorable to improve the power of solar cell piece, and improve the reliability of solar cell piece. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 The structure diagram of solar cell piece in prior art;

[0045] Figure 2 : Figure 1 The local enlarged view of area A in the middle;

[0046] Figure 3 : the structure diagram of the solar cell piece in the utility model;

[0047] Figure 4 : Figure 2 the local enlarged view of the B area in the middle;

[0048] Figure 5 : Figure 2 the local enlarged view of the C area in the middle;

[0049] Figure 6 : the local enlarged view of the second Pad point in the utility model;

[0050] Figure 7 : the local enlarged view of another second Pad point in the utility model.

[0051] Reference signs:

[0052] 100-solar cell piece; 110-first area; 120-second area; 1-first grid line; 2-second grid line; 3-first edge grid line; 4-second edge grid line; 5-first Pad point; 51-end point; 52-first side edge; 6-second Pad point; 61-end point; 62-first side edge; 7-third Pad point; 8-fourth Pad point; 9-gap. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical scheme and advantages of the utility model more clear, the following will make further detailed description to the utility model by specific embodiments.

[0054] In order to make the purpose, technical scheme and advantages of the utility model more clear, the following will make further detailed description to the utility model by specific embodiments. The examples of the described embodiments are shown in the accompanying drawings, wherein the same or similar reference signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary, only for explaining the utility model, and cannot be understood as limiting the utility model. In addition, it should be understood that the specific embodiments described herein are only used to explain the utility model, and not used to limit the utility model.

[0055] In the description of the present application, it should be understood that the terms "upper", "lower", "back", "front" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as limiting the present application.

[0056] In this application, unless specifically stated and limited otherwise, the "on" or "under" of a first feature with respect to a second feature can include the first and second features being directly in contact, or the first and second features not being directly in contact but being in contact through another feature between them. Moreover, the "on", "above", and "upper" of a first feature with respect to a second feature include the first feature being directly above and obliquely above the second feature, or only indicating that the first feature is higher than the second feature in horizontal height. The "under", "below", and "lower" of a first feature with respect to a second feature include the first feature being directly below and obliquely below the second feature, or only indicating that the first feature is lower than the second feature in horizontal height.

[0057] The disclosure below provides many different embodiments or examples for implementing different structures of the application. For the purpose of simplification of the present disclosure, certain examples of components and arrangements are described. These are, of course, merely examples and are in no way limiting of the present application. Furthermore, the present application can be implemented in different examples with several components and / or arrangements being repeated. Such repetitions are not further discussed in the present disclosure for the purpose of simplification and clarity. In addition, the present application provides examples of various specific processes and materials. One of ordinary skill in the art, however, can recognize that other processes can be applied and / or other materials can be used.

[0058] Reference herein to "an embodiment" or "implementation" means that a particular feature, component or characteristic described in connection with the embodiment or implementation can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessary that a separate or alternative embodiment be developed for each appearance of the phrase. It will be readily understood to those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0059] To solve the above problems, the utility model provides a solar cell piece 100, as shown in the figure, the back of the solar cell piece 100 is provided with first grid line 1 and second grid line 2, first grid line 1 and second grid line 2 along the first direction parallel and mutually alternate arrangement; Figure 3 As shown in the figure, the back of the solar cell piece 100 is provided with first grid line 1 and second grid line 2, first grid line 1 and second grid line 2 along the first direction parallel and mutually alternate arrangement;

[0060] Along the first direction, the two side edges of the back of the solar cell piece 100 are provided with first edge grid line 3 and second edge grid line 4 extending along the second direction, first edge grid line 3 is connected with first grid line 1, and second edge grid line 4 is connected with second grid line 2;

[0061] In the first direction, two ends of the solar cell 100 are provided with a first Pad point 5 and a second Pad point 6, the first Pad point 5 is connected with the first grid line 1, and the first Pad point 5 is connected with the first edge grid line 3, the second Pad point 6 is connected with the second grid line 2, and the second Pad point 6 is connected with the second edge grid line 4.

[0062] In the utility model, as shown in the figure, Figure 4 and Figure 5 As shown in the figure, by moving the first Pad point 5 and the second Pad point 6 from the inner position of the solar cell 100 to the first edge grid line 3 and the second edge grid line 4 respectively, and connecting with the first edge grid line 3 and the second edge grid line 4 respectively, the distance between the Pad point and the edge grid line is shortened, more first grid lines 1 and second grid lines 2 are corresponded, and the area of PN junction formed on the solar cell 100 is increased, which is beneficial to improve the power of the solar cell 100 and improve the reliability of the solar cell 100.

[0063] It can be understood that the first Pad point 5 and the first grid line 1 and the first edge grid line 3 have the same polarity, and the second Pad point 6 and the second grid line 2 and the second edge grid line 4 have the same polarity.

[0064] It should be noted that the first direction and the second direction intersect. Preferably, the first direction and the second direction are perpendicular to each other; more preferably, the first direction is the transverse direction of the solar cell 100, and the second direction is the longitudinal direction of the solar cell 100, and the two are perpendicular to each other. Of course, in other embodiments, the first direction and the second direction can also be other directions, and the present application does not limit this.

[0065] Optionally, at least one end point 51 of the first Pad point 5 is connected with the first edge grid line 3, and at least one end point 61 of the second Pad point 6 is connected with the second edge grid line 4. Through the connection of the end points 51, 61, a path can be formed between the first Pad point 5 and the first edge grid line 3, and the second Pad point 6 and the second edge grid line 4, which is helpful to more effectively collect current, thereby improving the photoelectric conversion performance of the cell.

[0066] Further, the first Pad point 5 is connected with 1-5 first grid lines 1; the second Pad point 6 is connected with 1-5 second grid lines 2. The connection with proper number of grid lines can reduce the conduction distance of current on the first grid line 1 or the second grid line 2, effectively reduce the series resistance of the component, thus reducing the power loss, improving the fill factor and output power of the battery. Moreover, the first Pad point 5 and the second Pad point 6 can also function as welding points for welding the battery piece with the external circuit. If connected with more grid lines, it may affect the stability of welding and the reliability of the battery. More preferably, the first Pad point 5 is connected with 2-5 first grid lines 1; the second Pad point 6 is connected with 2-5 second grid lines 2. In some specific and preferred embodiments, the height H1 of the first Pad point 5 along the second direction is 0.8-3 mm; the height H2 of the second Pad point 6 along the second direction is 0.8-3 mm. Exemplary height H1, H2 can be 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, 3 mm, but not limited thereto. It can be understood that the height H1 of the first Pad point 5 along the second direction can be equal to or different from the height H2 of the second Pad point 6 along the second direction. Alternatively, the first grid line 1 and the second grid line 2 can be formed by screen printing technology with silver paste. In this case, the width of the first grid line 1 and the second grid line 2 along the first direction can be 30-50 μm, and exemplary width can be 40 μm. Alternatively, the first grid line 1 and the second grid line 2 can be formed by depositing copper on the surface of the layer. In this case, the width of the first grid line 1 and the second grid line 2 along the first direction can be 170-190 μm, and exemplary width can be 180 μm.

[0067] When the first Pad point 5 is connected with 2-5 first grid lines 1, the two ends of the first Pad point 5 are respectively connected with the first grid lines 1 along the second direction. In some preferred embodiments, no second grid line 2 is arranged between the two first grid lines 1, so as to increase the area of the first Pad point 5 as much as possible, reduce the distance between the first Pad point 5 and the first edge grid line 3, avoid the operation of printing the second grid line 2 in the limited space, and reduce the process difficulty and production cost of the solar cell sheet 100. It can be understood that when the second Pad point 6 is connected with 2-5 second grid lines 2, the two ends of the second Pad point 6 are respectively connected with the second grid lines 2, no first grid line 1 is arranged between the two second grid lines 2, so as to increase the area of the first Pad point 5 as much as possible, reduce the distance between the first Pad point 5 and the first edge grid line 3, avoid the operation of printing the second grid line 2 in the limited space, and reduce the process difficulty and production cost of the solar cell sheet 100.

[0068] Optionally, the first Pad point 5 comprises a first side edge 52 arranged along the second direction, and the first Pad point 5 is connected with the first edge grid line 3 through the first side edge 52; the second Pad point 6 comprises a first side edge 62 arranged along the second direction, and the second Pad point 6 is connected with the second edge grid line 4 through the first side edge 62. By connecting through the first side edges 52, 62, the contact area of the first Pad point 5 and the first edge grid line 3 and the contact area of the second Pad point 6 and the second edge grid line 4 are increased, which not only can form a path and help to collect current more effectively, thereby improving the photoelectric conversion performance of the cell sheet, but also can enhance the stability of the edge of the cell sheet and reduce the performance decline caused by physical loss.

[0069] The shape of the first Pad point 5 and the second Pad point 6 will affect the connection with the first edge grid line 3 and the second edge grid line 4. Preferably, the shape of the first Pad point 5 is one of a triangle, a rectangle, a square, an L shape, a trapezoid, a circle and an irregular shape; the shape of the second Pad point 6 is one of a triangle, a rectangle, a square, an L shape, a trapezoid, a circle and an irregular shape, wherein the triangle can be one of a right triangle, an equilateral triangle, an isosceles triangle or a common triangle; the trapezoid can be one of a right trapezoid, an isosceles trapezoid or a common trapezoid, which is not limited in the present application.

[0070] Exemplarily, as shown in FIG. 1, the first Pad point 5 is connected with the first edge grid line 3 through the first side edge 52, and the second Pad point 6 is connected with the second edge grid line 4 through the first side edge 62. Figure 4or 5, the first Pad point 5 and the second Pad point 6 are both rectangular, and one side of the rectangle along the second direction is used as a first side 52, 62, and the Pad point is connected to the edge grid line through the first side 52, 62. It can be understood that the first side 52 of the first Pad point 5 overlaps the first edge grid line 3, and the first side 62 of the second Pad point 6 overlaps the second edge grid line 4. Of course, the first Pad point 5 and the second Pad point 6 can also be connected to the edge grid line through one end point of the rectangle.

[0071] As shown in the example of FIG. 5, the first Pad point 5 and the second Pad point 6 are both rectangular, and one side of the rectangle along the second direction is used as a first side 52, 62, and the Pad point is connected to the edge grid line through the first side 52, 62. It can be understood that the first side 52 of the first Pad point 5 overlaps the first edge grid line 3, and the first side 62 of the second Pad point 6 overlaps the second edge grid line 4. Of course, the first Pad point 5 and the second Pad point 6 can also be connected to the edge grid line through one end point of the rectangle. Figure 6 As shown in the example of FIG. 5, the first Pad point 5 and the second Pad point 6 are both rectangular, and one side of the rectangle along the second direction is used as a first side 52, 62, and the Pad point is connected to the edge grid line through the first side 52, 62. It can be understood that the first side 52 of the first Pad point 5 overlaps the first edge grid line 3, and the first side 62 of the second Pad point 6 overlaps the second edge grid line 4. Of course, the first Pad point 5 and the second Pad point 6 can also be connected to the edge grid line through one end point of the rectangle.

[0072] As shown in the example of FIG. 5, the first Pad point 5 and the second Pad point 6 are both rectangular, and one side of the rectangle along the second direction is used as a first side 52, 62, and the Pad point is connected to the edge grid line through the first side 52, 62. It can be understood that the first side 52 of the first Pad point 5 overlaps the first edge grid line 3, and the first side 62 of the second Pad point 6 overlaps the second edge grid line 4. Of course, the first Pad point 5 and the second Pad point 6 can also be connected to the edge grid line through one end point of the rectangle. Figure 7 As shown in the example of FIG. 5, the first Pad point 5 and the second Pad point 6 are both rectangular, and one side of the rectangle along the second direction is used as a first side 52, 62, and the Pad point is connected to the edge grid line through the first side 52, 62. It can be understood that the first side 52 of the first Pad point 5 overlaps the first edge grid line 3, and the first side 62 of the second Pad point 6 overlaps the second edge grid line 4. Of course, the first Pad point 5 and the second Pad point 6 can also be connected to the edge grid line through one end point of the rectangle. As shown in the example of FIG. 5, the first Pad point 5 and the second Pad point 6 are both rectangular, and one side of the rectangle along the second direction is used as a first side 52, 62, and the Pad point is connected to the edge grid line through the first side 52, 62. It can be understood that the first side 52 of the first Pad point 5 overlaps the first edge grid line 3, and the first side 62 of the second Pad point 6 overlaps the second edge grid line 4. Of course, the first Pad point 5 and the second Pad point 6 can also be connected to the edge grid line through one end point of the rectangle.

[0073] It can be understood that the shape of the first Pad point 5 can be the same as that of the second Pad point 6, or can be different. Of course, the shape of the first Pad point 5 and the shape of the second Pad point 6 can also be selected according to actual needs, and are not limited to the above range in the present application, and can also be a rhombus, an ellipse, etc.

[0074] Preferably, the area of the first Pad point 5 is 0.6mm 2 ~4mm 2 ; the area of the second Pad point 6 is 0.6mm 2 ~4mm 2 , and exemplary areas can be 0.6mm 2 , 1mm 2 , 1.5mm 2 , 2mm 2 , 2.5mm 2 , 3mm 2 , 3.5mm 2 , 4mm 2 , but are not limited thereto. If the areas of the first Pad point 5 and the second Pad point 6 are too large, not only the cost will be increased, but also the heat dissipation of the battery piece will be affected, and a hot spot effect will be generated.

[0075] Optionally, a solder strip (not marked in the figure) is arranged on the solar cell piece 100, the solder strip connects adjacent first Pad points 5 and second Pad points 6 in the second direction, each first grid line 1 and second grid line 2 is in contact with the solder strip through the first Pad point 5 and the second Pad point 6, and a main grid bus is not needed. The grid current at the edge passes through the first Pad point 5 and the second Pad point 6 from the first grid line 1 and the second grid line 2 and is directly led out to the solder strip, thereby reducing resistance loss, reducing shading area and paste consumption, and reducing manufacturing cost. However, the first Pad point 5 and the second Pad point 6 are located at the edge of the battery piece, and in the manufacturing process, the solder strip also needs to cover the edge of the silicon piece. There are a large number of microcracks at the edge of the silicon piece, and stress concentration will be caused in the soldering process of the solder strip, resulting in the problem of cracking of the silicon piece, reducing the yield of the assembly, and reducing the reliability of the assembly. Therefore, the width of the first Pad point 5 in the first direction is L1, the distance between the first Pad point 5 and the edge of the solar cell piece 100 is L2, L1=(0.15~0.85)L2 is satisfied, the width of the second Pad point 6 in the first direction is L3, the distance between the second Pad point 6 and the edge of the solar cell piece 100 is L4, L3=(0.15~0.85)L4 is satisfied, which is beneficial to dispersing the concentrated stress generated in the manufacturing process of the Pad point and the solder strip, improving the tolerance of the battery to hidden cracks, broken grids, and cracks, and improving the yield and reliability of the solar cell assembly.

[0076] Furthermore, the width of the first Pad point 5 and the second Pad point 6 in the first direction is greater than the width of the solder strip in the first direction, and the first Pad point 5 and the second Pad point 6 can also exist as test points. Generally, the width of the first Pad point 5 and the second Pad point 6 in the first direction is greater than 0.8 mm, ensuring that the probe is in full contact with them. In some embodiments, the width L1 of the first Pad point 5 along the first direction is 0.9 mm to 2 mm; the width L3 of the second Pad point 6 along the first direction is 0.9 mm to 2 mm; the first Pad point 5 and the second Pad point 6 can be in full contact with the solder strip as a welding point, and can also be in full contact with the probe when used as a test point, to ensure the accuracy and precision of the test performance. Exemplary widths L1 and L3 can be 0.9 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, and 2 mm, but are not limited thereto. It can be understood that the width L1 of the first Pad point 5 in the first direction can be equal to or unequal to the width L3 of the second Pad point 6 in the first direction.

[0077] In some embodiments, the width L5 of the first edge gridline 3 along the first direction is 30 μm to 400 μm, and the width L6 of the second edge gridline 4 along the first direction is 30 μm to 400 μm, which can cooperate with the pad point width of 0.9 mm to 2 mm to further promote the dispersion of concentrated stress, which is beneficial to improving the reliability of the resulting solar cell 100 and solar cell module. Exemplary widths L5 and L6 can be 30 μm, 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, and 400 μm, but are not limited thereto.

[0078] The edge grid lines of the solar cell 100 are usually divided into three sections, and the polarities of two adjacent sections are different, such as Figure 1 As shown, this is used to reduce the lateral current transmission distance, thereby reducing series resistance, improving the battery's fill factor and output power, and helping to more evenly collect current, improving the overall performance of the cell. However, the design and manufacturing process of this type of edge grid line is complex, leading to increased production costs.

[0079] In this application, if Figure 3As shown, the solar cell 100 includes a first region 110 and a second region 120. It should be noted that the solar cell 100 is designed as a half piece in the middle and the upper and lower parts are symmetrically arranged, wherein the first region 110 is located in the upper part and the second region 120 is located in the lower part. Along the second direction, both ends of the first region 110 and the second region 120 are provided with third Pad points 7 and fourth Pad points 8 which are alternately arranged along the first direction, the third Pad points 7 are connected with the first grid lines 1, and the fourth Pad points 8 are connected with the second grid lines 2.

[0080] Further, the first edge grid line 3 extends uninterruptedly from one end of the first region 110 to the other end of the first region 110 along the second direction and is connected with all the first grid lines 1; the first edge grid line 3 extends uninterruptedly from one end of the second region 120 to the other end of the second region 120 along the second direction and is connected with all the first grid lines 1; the second edge grid line 4 extends uninterruptedly from one end of the first region 110 to the other end of the first region 110 along the second direction and is connected with all the second grid lines 2; the second edge grid line 4 extends uninterruptedly from one end of the second region 120 to the other end of the second region 120 along the second direction and is connected with all the second grid lines 2. In this application, the first Pad points 5 and the second Pad points 6 are arranged at the corresponding first edge grid line 3 and second edge grid line 4, and by arranging the first edge grid line 3 as a same polarity grid line, a better current collecting effect can be achieved, the photoelectric conversion performance of the solar cell 100 is ensured, and the preparation of the solar cell 100 is simplified.

[0081] Specifically, the two ends of the first grid line 1 are not aligned with the two ends of the second grid line 2, one end of the first grid line 1 has a protruding end relative to one end of the second grid line 2, and the other end of the first grid line 1 has a shortened end relative to the other end of the second grid line 2; the first edge grid line 3 is connected with the protruding end of the first grid line 1, and the second edge grid line 4 is connected with the protruding end of the second grid line 2. It should be noted that the protruding end refers to the end of the first grid line 1 or the second grid line 2 which is closer to the edge grid line along the first direction; the shortened end refers to the end of the first grid line 1 or the second grid line 2 which is closer to the center of the solar cell 100 along the first direction.

[0082] Preferably, the first edge gate line 3, the second edge gate line 4, the first gate line 1 and the second gate line 2 are made of the same material. It can be understood that the same material here means that the raw materials used in the preparation of the first edge gate line 3, the second edge gate line 4, the first gate line 1 and the second gate line 2 are the same, but in the later detection results, the composition will change slightly due to the setting of the intermediate multiple structures, which belongs to the error range in the art. Alternatively, the main components of the material of the first edge gate line 3, the second edge gate line 4, the first gate line 1 and the second gate line 2 can be aluminum, silver, copper, tin, titanium, tungsten or alloys thereof, and the material of the first edge gate line 3, the second edge gate line 4, the first gate line 1 and the second gate line 2 is not specifically limited in the application.

[0083] Preferably, the first Pad point 5, the second Pad point 6, the third Pad point 7 and the fourth Pad point 8 are made of the same material. It can be understood that the same material here means that the raw materials used in the preparation of the first Pad point 5, the second Pad point 6, the third Pad point 7 and the fourth Pad point 8 are the same, but in the later detection results, the composition will change slightly due to the setting of the intermediate multiple structures, which belongs to the error range in the art. Alternatively, the main components of the material of the first Pad point 5, the second Pad point 6, the third Pad point 7 and the fourth Pad point 8 can be aluminum, silver, copper, tin, titanium, tungsten or alloys thereof, and the material of the first Pad point 5, the second Pad point 6, the third Pad point 7 and the fourth Pad point 8 is not specifically limited in the application.

[0084] Correspondingly, the utility model also provides a solar cell module, including the solar cell piece 100.

[0085] It can be understood that the solar cell module can further include a metal frame, a front plate, a back plate and a film.

[0086] The back plate can protect and support the battery string, has reliable insulation, water resistance and aging resistance, the back plate can have multiple choices, generally can be tempered glass, organic glass, aluminum alloy TPT composite film, KPC, CPC and the like, and the specific setting can be carried out according to specific circumstances, and the specific limitation is not made in the application.

[0087] The front plate, such as photovoltaic glass, can be covered on the adhesive film of the light-receiving surface of the solar cell, the front plate can be super white glass, which has high light transmittance, high transparency, and has superior physical, mechanical and optical properties, for example, the light transmittance of super white glass can reach more than 92%, which can protect the cell sheet 1 without affecting the efficiency of the cell sheet 1 as much as possible. At the same time, the adhesive film can bond the front plate and the solar cell together, and the adhesive film can seal, insulate and prevent water and moisture from the solar cell, and the adhesive film has multiple choices, including but not limited to one or more of the following: EPE adhesive film layer, EVA adhesive film layer, POE adhesive film layer, EVA-POE adhesive film layer. The whole of the back plate, the solar cell, the adhesive film and the front plate can be arranged on the metal frame, which serves as the main external support structure of the entire solar cell module, and can provide stable support and installation for the solar cell module, for example, the solar cell module can be installed at the desired installation position through the metal frame.

[0088] Correspondingly, the utility model also provides a photovoltaic system, it includes the solar cell module. It can be understood that each solar cell module can be electrically connected in parallel or in series, and the specific selection can be made according to actual needs.

[0089] In the embodiment, the photovoltaic system can be applied in photovoltaic power stations, such as ground power stations, roof power stations, water surface power stations, etc., and can also be applied in devices or apparatuses that use solar energy to generate electricity, such as user solar power sources, solar street lamps, solar cars, solar buildings, etc. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited to this, that is, the photovoltaic system can be applied in all fields that need to use solar energy to generate electricity. Taking a photovoltaic power generation system network as an example, the photovoltaic system can include a photovoltaic array, a combiner box and an inverter, the photovoltaic array can be an array combination of multiple cell modules, for example, multiple cell modules can form multiple photovoltaic arrays, the photovoltaic array is connected to the combiner box, the combiner box can combine the current generated by the photovoltaic array, the combined current flows through the inverter to convert into alternating current required by the power grid, and then is connected to the power network to realize solar power supply.

[0090] The above only discloses a preferred embodiment of the utility model, and of course cannot limit the scope of the utility model, so equivalent changes made according to the utility model claims still fall within the scope covered by the utility model.

Claims

1. A solar cell, characterized by, The back surface of the solar cell piece is provided with first grid lines and second grid lines, the first grid lines and the second grid lines are parallel and alternately arranged along a first direction; Along the first direction, the two side edges of the back surface of the solar cell piece are provided with first edge grid lines and second edge grid lines extending along a second direction, the first edge grid lines are connected with the first grid lines, and the second edge grid lines are connected with the second grid lines; Along the first direction, the two end portions of the solar cell piece are provided with first Pad points and second Pad points, the first Pad points are connected with the first grid lines, and the first Pad points are connected with the first edge grid lines, the second Pad points are connected with the second grid lines, and the second Pad points are connected with the second edge grid lines.

2. The solar cell of claim 1, wherein, At least one end point of the first Pad point is connected with the first edge grid line; At least one end point of the second Pad point is connected with the second edge grid line.

3. The solar cell of claim 1, wherein the first and second electrodes are formed of a material selected from the group consisting of silver, aluminum, and copper. The first Pad point comprises a first side edge arranged along the second direction, and the first Pad point is connected with the first edge grid line through the first side edge; The second Pad point comprises a first side edge arranged along the second direction, and the second Pad point is connected with the second edge grid line through the first side edge.

4. The solar cell according to any one of claims 1 to 3, wherein The first Pad point is connected with 1-5 first grid lines; The second Pad point is connected with 1-5 second grid lines.

5. The solar cell as claimed in claim 4, wherein the first and second electrodes are formed of a material selected from the group consisting of silver, aluminum, and copper. The first Pad point is connected with 2-5 first grid lines; The second Pad point is connected with 2-5 second grid lines.

6. The solar cell as claimed in claim 5, wherein the first and second electrodes are formed of a material selected from the group consisting of silver, aluminum, and copper. Along the second direction, the two end portions of the first Pad point are respectively connected with the first grid lines, and no second grid line is arranged between the two first grid lines; And / or, the two end portions of the second Pad point are respectively connected with the second grid lines, and no first grid line is arranged between the two second grid lines.

7. The solar cell as claimed in any one of claims 1 to 3, wherein The shape of the first Pad point is one of a triangle, a rectangle, a square, an L type, a trapezoid, a circle, and an irregular figure; The shape of the second Pad point is one of a triangle, a rectangle, a square, an L type, a trapezoid, a circle, and an irregular figure.

8. The solar cell as claimed in any one of claims 1 to 3, wherein The area of the first Pad point is 0.6mm 2 ~ 4mm 2 ; The area of the second Pad point is 0.6mm 2 ~ 4mm 2 .

9. The solar cell of claim 8, wherein the first and second conductive layers are formed of a material selected from the group consisting of silver, aluminum, copper, and combinations thereof. The width of the first Pad point along the first direction is L1, the distance between the first Pad point and the edge of the solar cell piece is L2, and L1=(0.15-0.85)L2 is satisfied; The width of the second Pad point along the first direction is L3, the distance between the second Pad point and the edge of the solar cell piece is L4, and L3=(0.15-0.85)L4 is satisfied.

10. The solar cell of claim 9, wherein the first and second conductive layers are formed of a material selected from the group consisting of silver, aluminum, and copper. The width L1 of the first Pad point along the first direction is 0.9mm-2mm; The width L3 of the second Pad point along the first direction is 0.9mm-2mm.

11. The solar cell of claim 8, wherein the first and second conductive layers are formed of a material selected from the group consisting of silver, aluminum, copper, and combinations thereof. The height H1 of the first Pad point along the second direction is 0.8mm-3mm; The height H2 of the second Pad point along the second direction is 0.8mm-3mm.

12. The solar cell of claim 8, wherein the back surface is textured. The width L5 of the first edge grid line along the first direction is 30μm-400μm; The width L6 of the second edge grid line along the first direction is 30μm-400μm.

13. The solar cell as claimed in any one of claims 1 to 3, wherein The solar cell is provided with a solder strip, which connects adjacent first Pad points in a second direction; And / or, the solar cell is provided with a solder strip, which connects adjacent second Pad points in a second direction.

14. The solar cell according to claim 1, wherein: The solar cell comprises a first region and a second region; In the second direction, both ends of the first region and the second region are provided with third Pad points and fourth Pad points arranged alternately in the first direction, the third Pad points are connected with the first grid lines, and the fourth Pad points are connected with the second grid lines.

15. The solar cell of claim 14, wherein the first and second conductive layers are formed of a material selected from the group consisting of silver, aluminum, copper, and combinations thereof. The first edge grid line and / or the second edge grid line extend uninterruptedly from one end of the first region to the other end of the first region in the second direction, and are connected with all the first grid lines or the second grid lines; The first edge grid line and / or the second edge grid line extend uninterruptedly from one end of the second region to the other end of the second region in the second direction, and are connected with all the first grid lines or the second grid lines.

16. The solar cell of claim 15, wherein the first and second conductive layers are formed of a material selected from the group consisting of silver, aluminum, copper, and combinations thereof. The two ends of the first grid lines are misaligned with the two ends of the second grid lines, one end of the first grid lines has a protruding end relative to one end of the second grid lines, and the other end of the first grid lines has a shortened end relative to the other end of the second grid lines; The first edge grid line is connected with the protruding end of the first grid line, and the second edge grid line is connected with the protruding end of the second grid line.

17. The solar cell of claim 1, wherein the back surface is textured. 17 The first edge grid line, the second edge grid line, the first grid line and the second grid line are made of the same material. The first Pad points, the second Pad points, the third Pad points and the fourth Pad points are made of the same material.

18. A solar cell module characterized by comprising: The solar cell comprises the solar cell according to any one of claims 17.

19. A photovoltaic system characterized by, The solar cell module comprises the solar cell module according to claim 18.

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