Solar cell and solar module

Abstract

The present application relates to the technical field of solar cells. Disclosed are a solar cell and a solar module, which aim to solve the problem of high manufacturing costs of a solar cell caused by high manufacturing costs of busbars. The solar cell comprises: busbar electrodes and finger electrodes, which are formed on the cell body, wherein a plurality of pads are arranged on each busbar electrode at intervals in a first direction. For each of at least some busbar electrodes, in a direction from a preset point on the busbar electrode to any pad on the busbar electrode that is adjacent to the preset point, the width of the busbar electrode is gradually increased, wherein the preset point is any point between any two adjacent pads on the busbar electrode where the preset point is located, and the width direction of the busbar electrode is consistent with a second direction. For each of the at least some busbar electrodes, Sz≥2×n×Sx, n being an integer greater than or equal to 1; the portion of the busbar electrode between the preset point located on the bus electrode and any pad on the busbar electrode that is adjacent to the preset point is defined as a first busbar electrode, and Sx represents the cross-sectional area of any finger electrode, which intersects the first busbar electrode, in the first direction; and for the nth finger electrode, which intersects the first busbar electrode in the direction from the preset point to the any pad, starting from the preset point on the busbar electrode, Sz represents the cross-sectional area of the first busbar electrode in the second direction at the intersection of the first busbar electrode and the nth finger electrode.

Description

Solar cell and solar module Technical Field

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

[0002] A solar cell is a semiconductor device that converts light energy into electrical energy. Specifically, when a solar cell is exposed to light, the semiconductor substrate it comprises absorbs photons and generates electron-hole pairs. These electron-hole pairs are separated by the built-in electric field within the PN junction and are respectively extracted through the solar cell's emitter and back field, ultimately being collected by electrode structures disposed on the semiconductor substrate.

[0003] The electrode structure typically includes a busbar, fine grids, and solder pads attached to the busbar. Currently, the busbar width is uniform across the board. While ensuring proper function in the busbar area connected to the solder pads, the busbar width away from the solder pads is wider. This increases the manufacturing cost of the busbar, and thus the solar cell.

[0004] Summary of the Invention

[0005] The purpose of the present application is to provide a solar cell and a solar module for reducing the manufacturing cost of a main grid, thereby reducing the manufacturing cost of the solar cell.

[0006] To achieve the above objectives, in a first aspect, the present application provides a solar cell. The solar cell comprises: a cell body, a busbar electrode, a solder pad, and a collector electrode. The busbar electrode is formed on the cell body, with multiple busbar electrodes extending along a first direction and spaced apart along a second direction, the first direction being different from the second direction. Multiple solder pads are spaced apart along the first direction on the busbar electrode. For each of at least one of the multiple busbar electrodes, the width of the busbar electrode gradually increases from a predetermined point on the busbar electrode to any solder pad adjacent to the predetermined point. The predetermined point is any point between any two adjacent solder pads on the busbar electrode where the predetermined point is located. The width of the busbar electrode is aligned with the second direction, and the direction from the predetermined point to any solder pad adjacent to the predetermined point on the busbar electrode where the predetermined point is located is parallel to the first direction. The collector electrode is formed on the cell body, with multiple collector electrodes extending along the second direction and spaced apart along the first direction. Each busbar electrode intersects with multiple collector electrodes of the same polarity. Among them, for each of the at least one bus electrode: Sz≥2×n×Sx, n is an integer greater than or equal to 1; the portion of the bus electrode located between the preset point on the bus electrode and any welding pad adjacent to the preset point on the bus electrode is defined as the first bus electrode, Sx represents the cross-sectional area of ​​any collecting electrode intersecting with the first bus electrode along the first direction; for the nth collecting electrode starting from the preset point on the bus electrode and intersecting with the first bus electrode in the direction from the preset point to the any welding pad, Sz represents the cross-sectional area of ​​the first bus electrode at the intersection with the nth collecting electrode along the second direction.

[0007] During actual use, the collecting electrode collects the carriers generated in the corresponding area of ​​the battery body, and the bus electrode is used to collect the carriers collected by the collecting electrode intersecting with it. Then, the bus electrode transfers the collected carriers to the soldering pad, and the soldering pad transfers them to the soldering ribbon connected to it. As the number of collecting electrodes intersecting with the bus electrode increases, the current density borne by the bus electrode continues to increase. Based on this, when the width of the bus electrode gradually increases from the preset point to any soldering pad adjacent to the preset point, the ability of the bus electrode to bear the current density can be improved, so as to improve the effect of the bus electrode in collecting current, thereby ensuring the performance of the solar cell. It should be understood that the minimum width of the bus electrode in this application meets the actual working needs. In other words, compared with the medium-width bus electrode in the prior art, the bus electrode width design in this application is more reasonable.

[0008] Furthermore, since the width of the bus electrode gradually increases along the direction from the preset point to any pad adjacent to the preset point, at this time, while ensuring that the area of ​​the bus electrode connected to the pad works normally and the size of the pad is basically the same or consistent with the size of the pad in the prior art (in other words, the maximum width of the bus electrode is basically the same, consistent with, or even smaller than the width of the bus electrode in the prior art), since the width of the bus electrode away from the pad gradually decreases, the amount of slurry used to make the bus electrode is less than the amount of slurry used when making equal-width bus electrodes in the prior art. Based on this, the production cost of the bus electrode can be reduced, thereby reducing the production cost of the solar cell. At the same time, compared with the medium-width bus electrode in the prior art, the bus electrode provided by the present application can also reduce the obstruction of the front of the battery body to improve the photoelectric conversion efficiency of the solar cell. Furthermore, since Sz≥2×n×Sx, the current conduction performance of the bus electrode can be guaranteed to be optimal when collecting current.

[0009] In one implementation, the above Sx is greater than or equal to 75 μm. 2 , and less than or equal to 375um 2 ; X1 is greater than or equal to 30um and less than or equal to 50um; wherein X1 represents the width of any collecting electrode intersecting with the first bus electrode, and the width direction of the collecting electrode is consistent with the first direction.

[0010] In this case, the manufacturing cost of the collecting electrode can be reduced while ensuring the ability of the collecting electrode to collect carriers, thereby further reducing the manufacturing cost of the solar cell.

[0011] In one implementation, the width Z1 of the first bus electrode is greater than or equal to a and less than or equal to b, wherein a is less than b; a is greater than or equal to 30 μm and less than or equal to 200 μm; and b is greater than or equal to 60 μm and less than or equal to 3 mm.

[0012] When adopting the above technical solution, the width of the first busbar electrode can be selected by comprehensively considering the cross-sectional area of ​​the collector electrode intersecting with it, the height of the first busbar electrode, or other influencing factors. In this case, not only the selectivity of the width of the first busbar electrode is increased, but also the scope of application of the first busbar electrode can be expanded.

[0013] In one implementation, for a bus electrode close to an edge of the battery body, collecting electrodes with the same polarity are spaced apart along the first direction only on one side thereof facing the adjacent bus electrode, thereby saving the cost of manufacturing the collecting electrodes.

[0014] The solar cell may further include a bridging busbar electrode, one end of which is connected to a busbar electrode near the edge of the cell body, and a soldering pad disposed at the other end of the bridging busbar electrode. The bridging busbar electrode is positioned between: the busbar electrode near the edge of the cell body; and the busbar electrode adjacent to the busbar electrode near the edge of the cell body. This ensures connectivity between the soldering pad and the busbar electrode near the edge of the cell body, thereby maintaining the performance of the solar cell.

[0015] In one implementation, at any position along the first direction, the width of the bus bar electrode close to the edge of the battery body is smaller than the width of the corresponding region of the adjacent bus bar electrode.

[0016] With this technical solution, because the busbar electrode near the edge of the cell body is only provided with a collector electrode intersecting with it on one side, the width of this busbar electrode can be reduced compared to the width of the corresponding area of ​​the adjacent busbar electrode. This reduces the manufacturing cost of the busbar electrode near the edge of the cell body while maintaining its performance, thereby reducing the manufacturing cost of the solar cell.

[0017] In one implementation, at any position along the first direction, the width of the bus bar electrode close to the edge of the battery body is 1 / 2 of the width of the corresponding area of ​​the adjacent bus bar electrode.

[0018] In one implementation, a projection of the bus electrode close to the edge of the battery body on the battery body includes a trapezoid and / or a triangle.

[0019] With the above technical solution, the cross-sectional area of ​​the busbar electrode near the edge of the battery body is ensured to meet actual needs, thereby increasing selectivity. In this case, the busbar electrode can be adapted to different application scenarios, thereby expanding the scope of application of solar cells.

[0020] In one implementation, the width of the overlapping bus electrode is equal to the maximum width of the bus electrode connected to the overlapping bus electrode, and the width direction of the overlapping bus electrode is consistent with the first direction.

[0021] When the above technical solution is adopted, it can not only ensure the ability of the overlapping busbar electrode to collect all carriers collected by the collecting electrodes, but also ensure the ability of the overlapping busbar electrode to transmit the collected current to the pad, thereby ensuring the performance of the solar cell.

[0022] In one implementation, the solar cell is a back-contact cell, and the busbar electrode is an N-region busbar electrode.

[0023] When adopting the above technical solution, since the N-region bus electrode is usually made of silver paste and the unit price of silver is relatively high, when the bus electrode provided in this application is the N-region bus electrode of the back-contact battery, the production cost of the bus electrode can be reduced while ensuring the performance of the bus electrode, thereby reducing the production cost of the solar cell.

[0024] In one implementation, the preset point is the center point between any two adjacent pads on the bus electrode where the preset point is located.

[0025] In a second aspect, the present application further provides a solar module, which includes the solar cell described in the above technical solution.

[0026] Compared with the prior art, the beneficial effects of the solar cell assembly provided in this application are the same as the beneficial effects of the solar cell described in the above technical solution, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0028] FIG1 is a schematic diagram of a partial structure of a solar cell in an embodiment of the present application;

[0029] FIG2 is a schematic cross-sectional view of a collector electrode in an embodiment of the present application;

[0030] FIG3 is a schematic cross-sectional view of a bus electrode in an embodiment of the present application;

[0031] FIG4 is an enlarged schematic diagram of a portion of the structure in FIG1 according to an embodiment of the present application;

[0032] FIG5 is a second enlarged schematic diagram of a portion of the structure in FIG1 according to an embodiment of the present application;

[0033] FIG6 is a schematic diagram of a partial structure of a solar cell in an embodiment of the present application;

[0034] FIG7 is an enlarged schematic diagram of part of the structure in FIG6 in an embodiment of the present application.

[0035] Reference numerals:

[0036] 1-bus electrode, 10-first bus electrode, 2-solder pad,

[0037] 3-collecting electrode, 4-preset point, 5-second bus electrode,

[0038] 6-Banding busbar electrode, A-first direction, B-second direction. DETAILED DESCRIPTION

[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0040] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0041] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0042] In the description of this application, it should be understood that the terms "up", "down", "front", "back", "left", "right", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on this application.

[0043] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0044] In order to solve the above technical problems, in the first aspect, an embodiment of the present application provides a solar cell. Referring to Figures 1 to 4, the solar cell includes: a battery body, a busbar electrode 1, a pad 2, and a collector electrode 3. The busbar electrode 1 is formed on the battery body, and a plurality of busbar electrodes 1 extend along a first direction A and are spaced apart along a second direction B, where the first direction is different from the second direction. For the busbar electrode 1, a plurality of pads 2 are spaced apart along the first direction on the busbar electrode 1. For each busbar electrode 1 of at least one of the plurality of busbar electrodes, the width of the busbar electrode 1 gradually increases along a direction from a preset point 4 on the busbar electrode 1 to any pad 2 adjacent to the preset point 4. The preset point 4 is any point between any two adjacent pads 2 on the busbar electrode 1 where the preset point 4 is located. The width direction of the busbar electrode 1 is consistent with the second direction, and the direction from the preset point 4 to any pad 2 adjacent to the preset point 4 on the busbar electrode where the preset point 4 is located is parallel to the first direction. The collecting electrodes 3 are formed on the battery body. The multiple collecting electrodes 3 extend along the second direction and are spaced apart along the first direction. Each busbar electrode 1 intersects with multiple collecting electrodes 3 of the same polarity. For each busbar electrode 1 of the at least one busbar electrode, Sz ≥ 2×n×Sx, where n is an integer greater than or equal to 1. The portion of the busbar electrode 1 located between a predetermined point 4 on the busbar electrode 1 and any pad 2 adjacent to the predetermined point 4 is defined as a first busbar electrode 10. Sx represents the cross-sectional area of ​​any collecting electrode 3 intersecting with the first busbar electrode 10 along the first direction. For the nth collecting electrode 3 that intersects with the first busbar electrode 10 starting from the predetermined point 4 on the busbar electrode 1 in the direction from the predetermined point 4 to the any pad, Sz represents the cross-sectional area of ​​the first busbar electrode 10 at the intersection with the nth collecting electrode 3 along the second direction.

[0045] The at least one bus electrode may be all or part of the multiple bus electrodes. In the case of the present application, the width of the at least one bus electrode is set to be gradual in order to save bus electrode material. Under this premise, whether the width of all or part of the bus electrodes is set to be gradual can be determined according to the specific circumstances. A typical example is that both aluminum bus electrodes and silver bus electrodes are included. Since silver is relatively expensive, the silver bus electrode can be designed to be gradual, that is, the width of the silver bus electrode is set to be gradual. However, aluminum is cheap and aluminum electrodes are difficult to print. There is no need to make the aluminum bus electrode gradual. Making the aluminum bus electrode gradual will introduce risks.

[0046] The structure and specifications of the battery body can be set according to actual conditions and are not specifically limited here. Furthermore, the first direction and the second direction can be any two directions parallel to the surface of the battery body and different from each other. Preferably, referring to Figure 1, the first direction A and the second direction B are orthogonal.

[0047] Referring to Figures 1 to 4 , during actual use, the collector electrode 3 collects carriers generated in the corresponding area of ​​the battery body, and the busbar electrode 1 is used to collect the carriers collected by the collector electrodes 3 intersecting with it. The busbar electrode 1 then transfers the collected carriers to the solder pad 2, which then transfers them to the solder ribbon connected to it. As the number of collector electrodes 3 intersecting with the busbar electrode 1 increases, the current density borne by the busbar electrode 1 continuously increases. Based on this, as the width of the busbar electrode 1 gradually increases from the preset point 4 to any solder pad 2 adjacent to the preset point 4, the ability of the busbar electrode 1 to bear the current density can be improved, thereby improving the effectiveness of the busbar electrode 1 in collecting current and thus ensuring the performance of the solar cell. It should be understood that the minimum width of the busbar electrode 1 in the embodiment of the present application meets actual working requirements. In other words, compared to the medium-width busbar electrodes in the prior art, the width design of the busbar electrode 1 in the embodiment of the present application is more reasonable.

[0048] Furthermore, since the width of the bus electrode 1 gradually increases along the direction from the preset point 4 to any pad 2 adjacent to the preset point 4, at this time, while ensuring that the area of ​​the bus electrode 1 connected to the pad 2 works normally and the size of the pad 2 is basically the same or consistent with the size of the pad in the prior art (in other words, the maximum width of the bus electrode 1 is basically the same, consistent with, or even smaller than the width of the bus electrode in the prior art), since the width of the bus electrode 1 away from the pad 2 gradually decreases, the amount of slurry used to make the bus electrode 1 is less than the amount of slurry used when making equal-width bus electrodes in the prior art. Based on this, the production cost of the bus electrode 1 can be reduced, thereby reducing the production cost of the solar cell. At the same time, compared with the medium-width bus electrode in the prior art, the bus electrode 1 provided in the embodiment of the present application can also reduce the obstruction of the front of the battery body, so as to improve the photoelectric conversion efficiency of the solar cell. Furthermore, a single bus electrode 1 needs to collect current from the collecting electrodes 3 on its left and right sides, and will preferentially select areas with smaller resistance for conduction. Therefore, when Sz≥2×n×Sx, it can ensure that the bus electrode 1 has the best current conduction performance when collecting current.

[0049] As a possible implementation, see Figure 2, Sx is greater than or equal to 75um 2 , and less than or equal to 375um 2 For example, Sx can be 75um 2 、95um 2 、124um 2 、150um 2 、196um 2 、260um 2 or 375um 2etc. X1 is greater than or equal to 30um and less than or equal to 50um; wherein X1 represents the width of any collecting electrode 3 intersecting with the first bus electrode 10, and the width direction of the collecting electrode 3 is consistent with the first direction. For example, X1 can be 30um, 33um, 35um, 40um, 42um, 48um or 50um, etc. The value of the above X1 is related to the specifications of the screen used for printing, and the screen line width can be adjusted according to different mass production requirements. At this time, the production cost of the collecting electrode 3 can be reduced while ensuring the ability of the collecting electrode 3 to collect carriers, thereby further reducing the production cost of the solar cell.

[0050] As a possible implementation, the cross-sectional shape of the collector electrode can be configured as needed, for example, to be triangular or quasi-triangular. Specifically, in the case of the quasi-triangular cross-sectional shape, the base of the cross-sectional shape is a straight line segment, and the remaining edge portions of the cross-sectional shape connecting the ends of the straight line segment are arc segments.

[0051] Referring to Figure 2, in the embodiment of the present application, the cross-sectional shape of the above-mentioned collecting electrode 3 is triangular. For example, the cross-sectional area Sx of the collecting electrode 3 is f×((X1×X2) / 2). Wherein, f represents an empirical coefficient, which is used to correct the actual cross-sectional area of ​​the collecting electrode 3. It should be understood that f will be affected by factors such as different machines, slurries, and the printing status of screen auxiliary materials. f is greater than 0 and less than or equal to 2. For example, f can be 0.1, 0.5, 1, 1.2, 1.6 or 2. X2 represents the height of any collecting electrode 3 that intersects with the first bus electrode 10, and the height direction of the collecting electrode 3 is perpendicular to both the first direction and the second direction. The value of the above-mentioned X2 is related to the specifications of the screen used for printing, and the screen thickness can be adjusted according to different mass production requirements. For example, the above-mentioned X2 is greater than or equal to 5um and less than or equal to 15um. For example, X2 can be 5um, 8um, 9um, 10um, 12um, 13um or 15um, etc.

[0052] As a possible implementation, referring to FIG5 , the spacing L between adjacent collector electrodes 3 of the same polarity can be set based on actual conditions and is not specifically limited herein. The spacing is along the first direction. For example, the spacing is solely dependent on the graphic design; once the graphic is finalized, the spacing is fixed.

[0053] As a possible implementation, referring to Figures 1 to 5 , the width Z1 of the first bus electrode 10 is greater than or equal to a and less than or equal to b, where a is less than b. Both a and b can be constants. For example, a is greater than or equal to 30 μm and less than or equal to 200 μm; b is greater than or equal to 60 μm and less than or equal to 3 mm. For example, Z1 can be 30 μm, 56 μm, 60 μm, 200 μm, 2500 μm, or 3000 μm; accordingly, a can be 30 μm, 45 μm, 56 μm, 80 μm, 130 μm, or 200 μm, and b can be 60 μm, 80 μm, 160 μm, 1000 μm, 2500 μm, or 3000 μm.

[0054] When adopting the above technical solution, the width of the first bus electrode 10 can be selected by comprehensively considering the cross-sectional area of ​​the collecting electrode 3 intersecting with it, the height of the first bus electrode 10, or other influencing factors. In this case, not only the width of the first bus electrode 10 is more selective, but also the scope of application of the first bus electrode 10 is expanded.

[0055] As a possible implementation, the cross-sectional shape of the first bus electrode can be set according to actual needs, for example, it can be rectangular, quasi-rectangular, square, quasi-square, etc. Specifically, when the cross-sectional shape is the quasi-rectangular or quasi-square shape, it means that the bottom side of the cross-sectional shape is a straight line segment, and the remaining edge portion of the cross-sectional shape connected to the ends of the straight line segment is an arc segment, or the edge portion of the cross-sectional shape opposite the straight line segment is an arc segment.

[0056] Referring to Figure 3, in the embodiment of the present application, the cross-sectional shape of the first bus electrode 10 is rectangular. Exemplarily, the cross-sectional area Sz of the first bus electrode 10 is Sz = Z1 × Z2; wherein Z2 represents the height of the first bus electrode 10, and the height direction of the first bus electrode 10 is perpendicular to both the first direction and the second direction. The value of Z2 is related to the specifications of the screen used for printing, and the screen thickness can be adjusted according to different mass production requirements. Exemplarily, Z2 is greater than or equal to 2um and less than or equal to 7um. For example, Z2 can be 2um, 2.5um, 3.6um, 4.9um, 5um, 6.2um, 6.8um, or 7um, etc.

[0057] As a possible implementation, referring to FIG. 1 , the preset point 4 is the center point between any two adjacent pads 2 on the bus electrode 1 where the preset point 4 is located.

[0058] The following describes the calculation process of the value of the width of the first bus electrode by taking a possible case as an example. It should be understood that the following description is only for understanding and is not intended to be a specific limitation.

[0059] 1 to 4, when the cross-sectional area Sx of the collector electrode 3 is 180 μm 2 The height Z2 of the first bus electrode 10 is 4.5 μm. The predetermined point 4 is the center point between two adjacent pads 2 on the bus electrode 1 where it is located. There are ten collecting electrodes 3 between these two pads 2. When the fifth collecting electrode 3 passes through this center point, a = (2 × 1 × 180) / 4.5 = 80 μm, and b = (2 × 5 × 180) / 4.5 = 400 μm. In other words, the width Z1 of the first bus electrode 10 is greater than or equal to 80 μm and less than or equal to 400 μm.

[0060] It should be understood that in actual manufacturing, it is not possible to ensure that a collector electrode will always pass through the preset point, but it is guaranteed that there will be a collector electrode around the preset point. Therefore, when calculating the minimum width of the first bus electrode, if no collector electrode passes through the preset point, the collector electrode closest to the preset point is selected for calculation.

[0061] As a possible implementation method, referring to Figures 6 and 7, for the bus electrode 1 close to the edge of the battery body (for the sake of convenience of description, it will be referred to as the second bus electrode 5), only on the side facing the adjacent bus electrode 1 (that is, the bus electrode 1 adjacent to the bus electrode 1 close to the edge of the battery body), collecting electrodes 3 with the same polarity are arranged at intervals along the first direction. In this case, the cost of making the collecting electrodes 3 can be saved.

[0062] Referring to Figures 6 and 7 , the solar cell further includes a bonding busbar electrode 6, one end of which is connected to a busbar electrode 1 near the edge of the cell body, and a soldering pad 2 disposed at the other end of the bonding busbar electrode 6. The bonding busbar electrode 6 is located between: a busbar electrode 1 near the edge of the cell body; and a busbar electrode 1 adjacent to the busbar electrode 1 near the edge of the cell body. This ensures connectivity between the soldering pad 2 and the busbar electrode 1 near the edge of the cell body, thereby guaranteeing the performance of the solar cell.

[0063] In one optional embodiment, the width of the busbar electrode 1 near the edge of the battery body is smaller than the width of the corresponding area of ​​the adjacent busbar electrode 1 (i.e., the busbar electrode 1 adjacent to the busbar electrode 1 near the edge of the battery body). That is, at any position along the first direction, the width of the busbar electrode 1 near the edge of the battery body is smaller than the width of the adjacent busbar electrode 1. Since the busbar electrode 1 near the edge of the battery body is only provided with a collector electrode 3 intersecting therewith on one side, the width of the busbar electrode 1 can be reduced compared to the width of the corresponding area of ​​the adjacent busbar electrode 1. Based on this, while ensuring the capacity of the busbar electrode 1 near the edge of the battery body, the production cost of the busbar electrode 1 can be reduced, thereby reducing the production cost of the solar cell.

[0064] In an optional manner, the width of the busbar electrode 1 close to the edge of the battery body is 1 / 2 of the width of the corresponding area of ​​the adjacent busbar electrode 1 .

[0065] In an optional manner, the projection of the busbar electrode 1 close to the edge of the battery body on the battery body includes a trapezoid and / or a triangle.

[0066] With the above technical solution, the selectivity is increased while ensuring that the cross-sectional area of ​​the busbar electrode 1 near the edge of the battery body meets actual needs. In this case, the busbar electrode 1 can be adapted to different application scenarios to expand the scope of application of solar cells.

[0067] For example, the projection of the busbar electrode 1 close to the edge of the battery body on the battery body may include only a trapezoid, or only a triangle, or of course may include both a trapezoid and a triangle.

[0068] In an optional manner, referring to FIG. 7 , the projection of the overlapping busbar electrode 6 on the battery body is a rectangle.

[0069] In one optional embodiment, referring to FIG7 , the width W of the overlapping busbar electrode 6 is equal to the maximum width of the busbar electrode 1 connected to the overlapping busbar electrode 6 (i.e., the maximum value of Z1), and the width direction of the overlapping busbar electrode 6 is consistent with the first direction. In this case, not only is the ability of the overlapping busbar electrode 6 to collect all carriers collected by the collector electrode 3 ensured, but the ability of the overlapping busbar electrode 6 to transmit the collected current to the pad 2 is also ensured, thereby ensuring the performance of the solar cell.

[0070] As a possible implementation manner, the solar cell is a back-contact cell, and the busbar electrode is an N-region busbar electrode.

[0071] N-region busbar electrodes are typically made of silver paste, which has a high unit price. Therefore, when the busbar electrode provided in this application is used as an N-region busbar electrode for a back-contact cell, the manufacturing cost of the busbar electrode can be reduced while ensuring the performance of the busbar electrode, thereby reducing the manufacturing cost of the solar cell.

[0072] In a second aspect, an embodiment of the present application further provides a solar module, which includes the solar cell described in the above technical solution.

[0073] Compared with the prior art, the beneficial effects of the solar cell assembly provided in the embodiment of the present application are the same as the beneficial effects of the solar cell described in the above technical solution, and will not be described in detail here.

[0074] As a possible implementation, the solar module further includes a welding ribbon, which is arranged on the welding pad along a first direction.

[0075] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0076] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the appended claims.

Claims

1. A solar cell comprising: Battery body; A bus electrode formed on the battery body; The plurality of bus electrodes extend along a first direction and are spaced apart along a second direction; the first direction is different from the second direction; A pad, for at least one of the plurality of bus electrodes: a plurality of pads are arranged at intervals on the at least one bus electrode along a first direction; along a direction from a preset point on the at least one bus electrode to any pad on the bus electrode where the preset point is located and adjacent to the preset point, the width of the bus electrode where the preset point is located gradually increases; the preset point is any point between any two adjacent pads on the bus electrode where the preset point is located; the width direction of the at least one bus electrode is consistent with the second direction, and the direction from the preset point to any pad on the bus electrode where the preset point is located and adjacent to the preset point is parallel to the first direction; A collector electrode is formed on the battery body; a plurality of the collector electrodes extend along the second direction and are spaced apart along the first direction; each of the bus electrodes intersects with a plurality of the collector electrodes having the same polarity; Wherein, Sz≥2×n×Sx, n is an integer greater than or equal to 1; a portion of the bus electrode located between the preset point and any of the pads adjacent to the preset point on the bus electrode where the preset point is located is defined as a first bus electrode; Sx represents any of the bus electrodes intersecting with the first bus electrode. The cross-sectional area of ​​the collector electrode along the first direction; for the nth collector electrode starting from the preset point on the bus electrode and intersecting with the first bus electrode in the direction from the preset point to any one of the welding pads, Sz represents the cross-sectional area of ​​the first bus electrode along the second direction at the intersection with the nth collector electrode.

2. The solar cell according to claim 1, wherein: Sx is greater than or equal to 75um 2 , and less than or equal to 375um 2 ; X1 is greater than or equal to 30um and less than or equal to 50um; Wherein, X1 represents the width of any of the collector electrodes intersecting with the first bus electrode, and the width direction of the collector electrode is consistent with the first direction.

3. The solar cell according to claim 1 or 2, wherein: The width Z1 of the first bus electrode is greater than or equal to a, and less than or equal to b; Among them, a is less than b; a is greater than or equal to 30um and less than or equal to 200um; b is greater than or equal to 60um and less than or equal to 3mm.

4. The solar cell according to claim 1, wherein: For the bus electrode close to the edge of the battery body, the collector electrodes with the same polarity are arranged at intervals along the first direction only on one side of the bus electrode facing the adjacent bus electrode; The solar cell further comprises a lapped bus electrode, one end of which is connected to the bus electrode near the edge of the battery body, and the pad is arranged at the other end of the lapped bus electrode; the lapped bus electrode is located between: the bus electrode near the edge of the battery body, and, the bus electrode adjacent to the bus electrode close to the edge of the battery body.

5. The solar cell according to claim 4, wherein: At any position along the first direction, the width of the bus electrode close to the edge of the battery body is smaller than the width of the corresponding area of ​​the adjacent bus electrode.

6. The solar cell according to claim 4 or 5, wherein: At any position along the first direction, the width of the bus electrode close to the edge of the battery body is 1 / 2 of the width of the corresponding area of ​​the adjacent bus electrode.

7. The solar cell according to claim 4, wherein: The projection of the bus electrode close to the edge of the battery body on the battery body includes a trapezoid and / or a triangle.

8. The solar cell according to claim 4, wherein: The width of the overlapping bus electrode is equal to the maximum value of the width of the bus electrode connected to the overlapping bus electrode; and the width direction of the overlapping bus electrode is consistent with the first direction.

9. The solar cell according to claim 1, wherein: The solar cell is a back contact cell, and the bus electrode is an N-region bus electrode; and / or, The preset point is the center point between any two adjacent pads on the bus electrode where the preset point is located.

10. A solar module comprising the solar cell according to any one of claims 1 to 9.

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