Solar cells and photovoltaic modules
By employing alternating positive and negative grid lines in the solar cell, and using positive and negative connection lines, the problems of weak current collection capability and low reliability of the grid line structure in the prior art are solved, achieving more efficient and reliable current collection and output.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TONGWEI SOLAR ENERGY (CHENGDU) CO LID
- Filing Date
- 2025-06-20
- Publication Date
- 2026-06-19
AI Technical Summary
The grid structure of existing gridless solar cells has a weak ability to collect photogenerated carriers and is prone to disconnection or poor soldering, resulting in low cell efficiency and reliability.
Alternating positive and negative grid lines are used, combined with positive and negative connecting lines, and electrical connection of grid lines with the same pole is achieved through welding, which increases the carrier collection capability and improves the stability of the grid line structure.
It improves the efficiency and reliability of solar cells, enhances the carrier collection capability of the grid structure at both ends of the cell, reduces the impact of poor soldering on current collection, and ensures stable current output.
Smart Images
Figure CN224386053U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of photovoltaic technology, and more specifically, to a solar cell and a photovoltaic module. Background Technology
[0002] Gridless (OBB) technology refers to solar cells that do not have a main grid; the grid structure consists only of thinner sub-grids. By eliminating the wider main grid, the amount of grid line material used can be reduced. Furthermore, in the module manufacturing process, solder ribbons can be used to replace the original main grid for current conduction, further achieving cost reduction and efficiency improvement.
[0003] Currently, in gridless solar cell designs, the positive and negative grid lines are arranged alternately, with each grid line parallel and aligned at both ends. This grid pattern results in a weak ability to collect photogenerated carriers at both ends of the solar cell (specifically, at both ends along the grid line extension direction). Furthermore, any break in the grid line printing process or any poor soldering during the welding process will prevent the effective collection of carriers in the end regions, leading to a reduction in module power. Therefore, existing solar cells have relatively low reliability and efficiency. Utility Model Content
[0004] The purpose of this application is to provide a solar cell and photovoltaic module with high cell efficiency and reliability.
[0005] The embodiments of this application can be implemented as follows:
[0006] In a first aspect, this application provides a solar cell, including a cell substrate and a grid structure disposed on the surface of the cell substrate. The grid structure includes a plurality of grid lines spaced apart in a first direction, the grid lines extending along a second direction, and the plurality of grid lines including alternating positive grid lines and negative grid lines. The grid structure also includes a plurality of welded portions arranged in multiple columns, the multiple columns of welded portions being arranged in the second direction, the welded portions in the same column having the same polarity and being disposed on different grid lines respectively; the first and last columns of welded portions in the second direction are respectively positive welded portions and negative welded portions.
[0007] The grid structure also includes a positive electrode connection line and a negative electrode connection line disposed on the battery substrate. The positive electrode connection line connects the ends of at least two positive electrode grid lines, and the row of welded parts closest to the positive electrode connection line is the negative electrode welded part; the negative electrode connection line connects the ends of at least two negative electrode grid lines, and the row of welded parts closest to the negative electrode connection line is the positive electrode welded part.
[0008] In an optional embodiment, multiple rows of positive electrode welding portions and multiple rows of negative electrode welding portions are arranged alternately in the second direction.
[0009] In an optional embodiment, the plurality of positive gate lines include a first positive gate line and a second positive gate line. The plurality of first positive gate lines form a first positive gate line array, and the plurality of second positive gate lines form two second positive gate line arrays. The two second positive gate line arrays are respectively located on both sides of the first positive gate line array in a first direction. The plurality of negative gate lines include a first negative gate line and a second negative gate line. The plurality of first negative gate lines form a first negative gate line array, and the plurality of second negative gate lines form two second negative gate line arrays. The two second negative gate line arrays are respectively located on both sides of the first negative gate line array in a first direction.
[0010] A positive busbar is provided at one end of the second positive grid array in the second direction, and the positive busbar is connected to the ends of multiple second positive grids; a negative busbar is provided at the other end of the second negative grid array in the second direction, and the negative busbar is connected to the ends of multiple negative grids; a positive connecting line is connected to the end of the first positive grid, and a negative connecting line is connected to the end of the first negative grid. In the second direction, the positive connecting line and the negative busbar are located on the same side of the grid structure, and the negative connecting line and the positive busbar are located on the same side of the grid structure.
[0011] In an optional embodiment, each column of positive electrode welding portions includes a plurality of first positive electrode welding portions and two second positive electrode welding portions, wherein the plurality of first positive electrode welding portions are respectively disposed on a plurality of first positive electrode grid lines, and the two second positive electrode welding portions are respectively disposed on two second positive electrode grid line arrays, and the second positive electrode welding portions are connected to the second positive electrode grid line in the second positive electrode grid line array that is closest to the first positive electrode grid line array.
[0012] Each column of negative electrode welding section includes multiple first negative electrode welding sections and two second negative electrode welding sections. The multiple first negative electrode welding sections are respectively disposed on multiple first negative electrode grid lines, and the two second negative electrode welding sections are respectively disposed on two second negative electrode grid line arrays. The second negative electrode welding section is connected to the second negative electrode grid line in the second negative electrode grid line array that is closest to the first negative electrode grid line array.
[0013] In an optional embodiment, each second positive gate line includes multiple positive sub-gate lines spaced apart in the second direction, and each second negative gate line includes multiple negative sub-gate lines spaced apart in the second direction.
[0014] At least a portion of the second positive electrode welding portion is connected to a plurality of positive electrode sub-grid lines belonging to different second positive electrode grid lines, and at least a portion of the second negative electrode welding portion is connected to a plurality of negative electrode grid lines belonging to different second negative electrode grid lines.
[0015] In an optional embodiment, the two ends of the positive electrode connection line are respectively connected to the ends of two adjacent first positive electrode grid lines; the two ends of the negative electrode connection line are respectively connected to the ends of two adjacent first negative electrode grid lines.
[0016] In an optional implementation, the positive electrode connection line is connected to the ends of all the first positive electrode grid lines, and the negative electrode connection line is connected to the ends of all the first negative electrode grid lines.
[0017] In an optional implementation, a chamfer is formed at the connection between the positive busbar and the second positive busbar furthest from the first positive busbar array; a chamfer is formed at the connection between the negative busbar and the second negative busbar furthest from the first negative busbar array.
[0018] In an optional implementation, the spacing between two adjacent first positive grid lines is X1, and the spacing between the end of the first negative grid line near the positive connection line and the positive connection line in the second direction is D1, where D1 / X1 is 0.1~0.3.
[0019] The spacing between two adjacent first negative grid lines is X2, and the spacing between the end of the first positive grid line near the negative connection line and the negative connection line in the second direction is D2, where D2 / X2 is 0.1~0.3.
[0020] Secondly, this application provides a photovoltaic module, including the solar cell of any of the foregoing embodiments.
[0021] The beneficial effects of the solar cells and photovoltaic modules provided in this application include:
[0022] The solar cell of this application embodiment includes a cell substrate and a grid structure disposed on the surface of the cell substrate. The grid structure includes a plurality of grid lines spaced apart in a first direction, extending along a second direction, and the plurality of grid lines include alternating positive and negative grid lines. The grid structure also includes a plurality of welded portions arranged in multiple columns, arranged in the second direction, with welded portions in the same column having the same polarity and disposed on different grid lines; the first and last columns of welded portions in the second direction are respectively positive and negative welded portions. The grid structure also includes positive and negative connecting lines disposed on the cell substrate, the positive connecting line connecting the ends of at least two positive grid lines, and the column of welded portions closest to the positive connecting line being a negative welded portion; the negative connecting line connecting the ends of at least two negative grid lines, and the column of welded portions closest to the negative connecting line being a positive welded portion. The positive and negative electrode connection lines can collect charge carriers from the battery substrate. Located adjacent to both ends of the battery substrate in the second direction, these lines increase the charge carrier collection capability of the grid structure at both ends of the battery substrate, thus improving battery efficiency. The negative and positive electrode connection lines achieve electrical connection between the same-pole grid lines, increasing the stability of the ends of the negative and positive grid lines, making them less prone to separation from the battery substrate. Furthermore, even in the event of a poor solder joint (failure of the solder joint between the solder strip and the grid line), the current on the grid line can be transferred through either the positive or negative electrode connection line to another grid line of the same pole, and further to the solder strip, thereby achieving current collection and output. Therefore, the solar cell provided in this application embodiment has superior reliability. In addition, the row of welded sections closest to the positive electrode connection line is the negative electrode welded section, and the row of welded sections closest to the negative electrode connection line is the positive electrode welded section. This is conducive to the uniform distribution of the positive and negative electrode parts of the grid structure, avoiding excessively high or low density of single polarity distribution in local areas, and further improving the uniform distribution of carrier collection capability and the reliability of solar cells. Attached Figure Description
[0023] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 This is a schematic diagram of a solar cell in related technologies;
[0025] Figure 2 This is a schematic diagram of a solar cell in one embodiment of this application;
[0026] Figure 3 This is a schematic diagram of a solar cell in another embodiment of this application;
[0027] Figure 4 This is a partial schematic diagram of a solar cell in one embodiment of this application.
[0028] Icons: 100 - Battery substrate; 210 - First positive electrode grid line; 211 - First positive electrode welded part; 212 - Positive electrode connecting line; 220 - Second positive electrode grid line; 221 - Second positive electrode welded part; 222 - Positive electrode busbar grid line; 310 - First negative electrode grid line; 311 - First negative electrode welded part; 312 - Negative electrode connecting line; 320 - Second negative electrode grid line; 321 - Second negative electrode welded part; 322 - Negative electrode busbar grid line. Detailed Implementation
[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0030] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0031] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0032] In the description of this application, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use, 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 orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0033] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0034] It should be noted that, where there is no conflict, the features in the embodiments of this application can be combined with each other.
[0035] Figure 1This is a schematic diagram of a solar cell in related technologies. (For example...) Figure 1 As shown, in related technologies, positive and negative grid lines are alternately arranged on the battery substrate, with the left and right ends of the grid lines aligned. There is a certain gap between the left and right edges of the battery substrate and the grid lines. Therefore, charge carriers in the left and right end regions of the battery substrate are mainly collected through the ends of the grid lines. However, the coverage area of the grid line ends is small, resulting in weak charge carrier collection capacity and low battery efficiency. Furthermore, the reliability of the grid line ends is poor, and they are prone to peeling (lifting) from the battery substrate, preventing the collection of charge carriers. When there is a poor weld between the solder strip and the grid line, the charge carriers collected by the grid lines cannot be efficiently collected onto the solder strip, affecting battery performance.
[0036] Therefore, embodiments of this application provide a solar cell that connects the ends of some of the same-polarity grid lines by setting positive and negative electrode connection lines. This improves the carrier collection capability of the grid line structure at both ends of the solar cell, thereby increasing cell efficiency and grid line reliability. Furthermore, embodiments of this application also provide a photovoltaic module including the aforementioned solar cell.
[0037] Figure 2 This is a schematic diagram of a solar cell in one embodiment of this application. Figure 2 As shown, the solar cell includes a cell substrate 100 and a grid structure disposed on the surface of the cell substrate 100. The grid structure includes a plurality of grid lines spaced apart in a first direction, extending along a second direction, and the plurality of grid lines include alternating positive and negative grid lines. The grid structure also includes a plurality of welded portions arranged in multiple rows in the second direction, with welded portions in the same row having the same polarity and disposed on different grid lines; the first and last rows of welded portions in the second direction are respectively positive and negative electrode welded portions. Figure 2 In this embodiment, the weld portions filled with diagonal lines are weld portions of the same polarity, and the weld portions without diagonal lines are weld portions of the other polarity. In this embodiment, the weld portions filled with diagonal lines are positive electrode weld portions, and the weld portions without diagonal lines are negative electrode weld portions. Multiple rows of positive electrode weld portions and multiple rows of negative electrode weld portions are arranged alternately in the second direction; along the second direction, the leftmost row of weld portions is the positive electrode weld portion, and the rightmost row of weld portions is the negative electrode weld portion. In this embodiment, there are a total of 23 grid lines, including 12 positive grid lines and 11 negative grid lines. The grid lines at both ends in the first direction are positive grid lines.
[0038] In this embodiment, the grid structure further includes a positive electrode connection line 212 and a negative electrode connection line 312 disposed on the battery substrate 100. The positive electrode connection line 212 connects the ends of at least two positive electrode grid lines, and the row of welded portions closest to the positive electrode connection line 212 is the negative electrode welded portion; the negative electrode connection line 312 connects the ends of at least two negative electrode grid lines, and the row of welded portions closest to the negative electrode connection line 312 is the positive electrode welded portion. Figure 2 As shown, the positive electrode connection line 212 is located on the right side of the entire grid structure in the second direction, and the row of welded portions closest to the positive electrode connection line 212 is the negative electrode welded portion; while the negative electrode connection line 312 is located on the left side of the entire grid structure in the second direction, and the row of welded portions closest to the negative electrode connection line 312 is the positive electrode welded portion. The positive electrode connection line 212 and the negative electrode connection line 312 are connected to the battery substrate 100, thus providing more points for collecting charge carriers and improving the charge carrier collection efficiency. The battery substrate 100 originally had a sparse grid distribution and weak charge carrier collection capability at both ends in the second direction. By adding the positive electrode connection line 212 and the negative electrode connection line 312, the charge carrier collection points become more uniform. Furthermore, the positive electrode connection line 212 and the negative electrode connection line 312 can also improve the end reliability of the positive and negative electrode grid lines, reducing the risk of peeling and warping. By placing the positive electrode connection line 212 near the negative electrode welding part and the negative electrode connection line 312 near the positive electrode welding part, the uniformity of the distribution of the positive and negative electrode portions of the grid structure can be increased.
[0039] It should be understood that the positive and negative portions of the grid structure should be connected to the p-type doped region and the n-type doped region of the solar cell, respectively, with the p-type doped region and the n-type doped region spaced apart on the cell substrate 100.
[0040] In this embodiment, the plurality of positive gate lines include a first positive gate line 210 and a second positive gate line 220. The plurality of first positive gate lines 210 constitute a first positive gate line array, and the plurality of second positive gate lines 220 constitute two second positive gate line arrays. The two second positive gate line arrays are respectively located on both sides of the first positive gate line array in a first direction. Correspondingly, the plurality of negative gate lines include a first negative gate line 310 and a second negative gate line 320. The plurality of first negative gate lines 310 constitute a first negative gate line array, and the plurality of second negative gate lines 320 constitute two second negative gate line arrays. The two second negative gate line arrays are respectively located on both sides of the first negative gate line array in a first direction. Figure 2In this embodiment, the first positive grid array and the first negative grid array are located in the middle region of the solar cell in the first direction, and the two second positive grid arrays and the two first negative grid arrays are located at both ends of the solar cell in the first direction. In this embodiment, the first positive grid array contains a total of 6 first positive grid lines 210, the first negative grid array contains a total of 5 first negative grid lines 310, each second positive grid array contains 3 second positive grid lines 220, and each second negative grid array contains 3 second negative grid lines 320. The first positive grid lines 210 and the first negative grid lines 310 are arranged alternately, as are the second positive grid lines 220 and the second negative grid lines 320. It should be understood that the number of first positive grid lines 210, first negative grid lines 310, second positive grid lines 220, and second negative grid lines 320 can be adjusted as needed.
[0041] In this embodiment, a positive busbar 222 is provided at one end of the second positive gate array in the second direction, and the positive busbar 222 is connected to the ends of a plurality of second positive gates 220; a negative busbar 322 is provided at the other end of the second negative gate array in the second direction, and the negative busbar 322 is connected to the ends of a plurality of negative gates. A positive connecting line 212 is connected to the end of the first positive gate 210, and a negative connecting line 312 is connected to the end of the first negative gate 310. In the second direction, the positive connecting line 212 and the negative busbar 322 are located on the same side of the gate structure, and the negative connecting line 312 and the positive busbar 222 are located on the same side of the gate structure. Since the positive busbar 222 needs to collect current from three different second positive busbars 220, and the negative busbar 322 needs to collect current from three different second negative busbars 320, the widths of the positive busbar 222 and the negative busbar 322 can be greater than the widths of the first positive busbar 210, the second positive busbar 220, the first negative busbar 310, and the second negative busbar 320. Because the battery substrate 100 has chamfers, to match the shape of the battery substrate 100, a chamfer is formed at the connection point between the positive busbar 222 and the second positive busbar 220 furthest from the first positive busbar array, and a chamfer is formed at the connection point between the negative busbar 322 and the second negative busbar 320 furthest from the first negative busbar array.
[0042] In this embodiment, each column of positive electrode welding portions includes a plurality of first positive electrode welding portions 211 and two second positive electrode welding portions 221. The plurality of first positive electrode welding portions 211 are respectively disposed on a plurality of first positive electrode grid lines 210, and the two second positive electrode welding portions 221 are respectively disposed on two second positive electrode grid line arrays. The second positive electrode welding portions 221 are connected to the second positive electrode grid line 220 in the second positive electrode grid line array that is closest to the first positive electrode grid line array.
[0043] Correspondingly, each column of negative electrode welding section includes multiple first negative electrode welding sections 311 and two second negative electrode welding sections 321. The multiple first negative electrode welding sections 311 are respectively disposed on multiple first negative electrode grid lines 310, and the two second negative electrode welding sections 321 are respectively disposed on two second negative electrode grid line arrays. The second negative electrode welding section 321 is connected to the second negative electrode grid line 320 in the second negative electrode grid line array that is closest to the first negative electrode grid line array.
[0044] In this embodiment, the structures of the first positive gate line 210 and the second positive gate line 220 are different, and the structures of the first negative gate line 310 and the second negative gate line 320 are different. Both the first positive gate line 210 and the first negative gate line 310 are gate lines extending continuously along the second direction, while each second positive gate line 220 includes multiple positive sub-gate lines spaced apart in the second direction, and each second negative gate line 320 includes multiple negative sub-gate lines spaced apart in the second direction. At least a portion of the second positive welding portion 221 is connected to multiple positive sub-gate lines belonging to different second positive gate lines 220, and at least a portion of the second negative welding portion 321 is connected to multiple negative sub-gate lines belonging to different second negative gate lines 320. Specifically, in this embodiment, except for the leftmost second positive welding portion 221, the other second positive welding portions 221 are connected to multiple positive sub-gate lines of different second positive gate lines 220.
[0045] In this embodiment, a first positive electrode solder joint 211 is connected to only one first positive electrode gate line 210, while a second positive electrode solder joint 221 can be connected to multiple second positive electrode gate lines 220. Therefore, the size of the second positive electrode solder joint 221 is larger than that of the first positive electrode solder joint 211, which allows it to withstand a larger current; and, a portion of the second positive electrode solder joint 221 has a soldering portion and an extension portion. The soldering portion is connected to the second positive electrode gate line 220 closest to the first positive electrode gate line array, and the extension portion extends away from the first positive electrode gate line array and connects to other second positive electrode gate lines 220. Figure 2 As shown, except for the leftmost second positive electrode welding portion 221, the welding portions of the other second positive electrode welding portions 221 are connected to the second positive electrode grid line 220 closest to the first positive electrode grid line array in their respective second positive electrode grid line arrays, and their extension portions are connected to other second positive electrode grid lines 220. The blank areas between the negative electrode sub-grid lines of the second negative electrode grid line 320 avoid the second positive electrode welding portion 221. Similarly, the blank areas between the positive electrode sub-grid lines of the second positive electrode grid line 220 also avoid the second negative electrode welding portion 321.
[0046] It is understood that the shape and arrangement of the second negative electrode welding portion 321 are similar to those of the second positive electrode welding portion 221, and will not be described in detail here. The welding portions in the second positive electrode welding portion 221 and the second negative electrode welding portion 321 are used for welding with the welding strip, and the welding portions are connected to the second positive electrode grid line 220 (or the second negative electrode grid line 320) closest to the center of the solar cell. This ensures that the welding position is not too close to the edge of the battery substrate 100 in the first direction, which can alleviate the problem of warping of the battery substrate 100 caused by the thermal stress of welding.
[0047] exist Figure 2 In this embodiment, the two ends of the positive electrode connection line 212 are respectively connected to the ends of two adjacent first positive electrode gate lines 210; the two ends of the negative electrode connection line 312 are respectively connected to the ends of two adjacent first negative electrode gate lines 310. Figure 2 As shown, the grid structure contains a total of 3 positive terminal connection lines 212 and 2 negative terminal connection lines 312.
[0048] Figure 3 This is a schematic diagram of a solar cell in another embodiment of this application. Figure 2 The difference in the embodiments is that, Figure 3 In this embodiment, the positive electrode connection line 212 connects to the ends of all the first positive electrode grid lines 210, and the negative electrode connection line 312 connects to the ends of all the first negative electrode grid lines 310.
[0049] In this embodiment, the positive electrode connection line 212 and the negative electrode connection line 312 are both straight line segments extending along the first direction. In other embodiments, the positive electrode connection line 212 and the negative electrode connection line 312 may also be other shapes such as broken lines or curves.
[0050] Figure 4 This is a partial schematic diagram of a solar cell in one embodiment of this application. Figure 4 As shown, the spacing between two adjacent first positive gate lines 210 is X1, and the spacing between the end of the first negative gate line 310 closest to the positive connection line 212 and the positive connection line 212 in the second direction is D1, where D1 / X1 is 0.1~0.3. This ensures that the positive connection line 212 and the first negative gate line 310 have sufficient spacing, making short circuits less likely, while also preventing the carrier collection capability from weakening due to an excessively large spacing D1.
[0051] Correspondingly, the spacing between two adjacent first negative grid lines 310 is X2, and the spacing between the end of the first positive grid line 210 near the negative connection line 312 and the negative connection line 312 in the second direction is D2, where D2 / X2 is 0.1~0.3.
[0052] This application also provides a photovoltaic module (not shown in the figure), including the solar cell provided in the above embodiments. The photovoltaic module also includes a solder strip, and a row of soldered portions in the solar cell is soldered to the same solder strip. The grid structure collects current and then converges it to the solder strip for outward output.
[0053] In summary, this application provides a solar cell, including a cell substrate 100 and a grid structure disposed on the surface of the cell substrate 100. The grid structure includes a plurality of grid lines spaced apart in a first direction, extending along a second direction, and the plurality of grid lines include alternating positive and negative grid lines. The grid structure also includes a plurality of welded portions arranged in multiple columns, arranged in a second direction, with welded portions in the same column having the same polarity and disposed on different grid lines; the first and last columns of welded portions in the second direction are respectively positive and negative welded portions. The grid structure also includes a positive connecting line 212 and a negative connecting line 312 disposed on the cell substrate 100, the positive connecting line 212 connecting the ends of at least two positive grid lines, and the column of welded portions closest to the positive connecting line 212 being a negative welded portion; the negative connecting line 312 connecting the ends of at least two negative grid lines, and the column of welded portions closest to the negative connecting line 312 being a positive welded portion. The positive electrode connection line 212 and the negative electrode connection line 312 can collect charge carriers from the battery substrate 100. Since the positive electrode connection line 212 and the negative electrode connection line 312 are located adjacent to both ends of the battery substrate 100 in the second direction, they can increase the charge carrier collection capability of the grid structure at both ends of the battery substrate 100, thereby improving battery efficiency. The negative electrode connection line 312 and the positive electrode connection line 212 achieve electrical connection of the same-pole grid lines. This not only increases the stability of the ends of the negative and positive grid lines, making them less prone to separation from the battery substrate 100, but also allows the current on the grid lines to be transferred to another same-pole grid line through the positive electrode connection line 212 or the negative electrode connection line 312 when a poor solder joint occurs (the connection between the solder strip and the welded part on the grid line fails), and further transferred to the solder strip, thereby achieving current collection and output. Therefore, the solar cell provided in this application embodiment has better reliability. In addition, the row of welded parts closest to the positive electrode connection line 212 is the negative electrode welded part, and the row of welded parts closest to the negative electrode connection line 312 is the positive electrode welded part. This is conducive to the uniform distribution of the positive and negative electrode parts of the grid structure, avoiding excessively high or low single polarity distribution density in local areas, and further improving the uniform distribution of carrier collection capability and the reliability of the solar cell.
[0054] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.
Claims
1. A solar cell, characterized in that, The device includes a battery substrate and a grid structure disposed on the surface of the battery substrate. The grid structure includes a plurality of grid lines spaced apart in a first direction, the grid lines extending along a second direction, and the plurality of grid lines including alternating positive and negative grid lines. The grid structure also includes a plurality of welded portions arranged in multiple columns in the second direction. The welded portions in the same column have the same polarity and are disposed on different grid lines. The first and last columns of welded portions in the second direction are respectively positive and negative welded portions. The grid structure further includes a positive electrode connection line and a negative electrode connection line disposed on the battery substrate. The positive electrode connection line connects the ends of at least two of the positive electrode grid lines, and the column of welded portions closest to the positive electrode connection line is the negative electrode welded portion. The negative electrode connection line connects the ends of at least two of the negative electrode grid lines, and the column of welded portions closest to the negative electrode connection line is the positive electrode welded portion.
2. The solar cell according to claim 1, characterized in that, The positive electrode welding portions and the negative electrode welding portions are arranged alternately in the second direction.
3. The solar cell according to claim 1, characterized in that, The plurality of positive gate lines includes a first positive gate line and a second positive gate line. The plurality of first positive gate lines form a first positive gate line array, and the plurality of second positive gate lines form two second positive gate line arrays. The two second positive gate line arrays are respectively located on both sides of the first positive gate line array in the first direction. The plurality of negative gate lines includes a first negative gate line and a second negative gate line. The plurality of first negative gate lines form a first negative gate line array, and the plurality of second negative gate lines form two second negative gate line arrays. The two second negative gate line arrays are respectively located on both sides of the first negative gate line array in the first direction. The second positive gate array has a positive busbar at one end in the second direction, and the positive busbar is connected to the ends of a plurality of second positive gates; the second negative gate array has a negative busbar at the other end in the second direction, and the negative busbar is connected to the ends of a plurality of negative gates; the positive connecting line is connected to the end of the first positive gate, and the negative connecting line is connected to the end of the first negative gate; in the second direction, the positive connecting line and the negative busbar are located on the same side of the gate structure, and the negative connecting line and the positive busbar are located on the same side of the gate structure.
4. The solar cell according to claim 3, characterized in that, Each column of positive electrode welding portions includes multiple first positive electrode welding portions and two second positive electrode welding portions. The multiple first positive electrode welding portions are respectively disposed on multiple first positive electrode grid lines, and the two second positive electrode welding portions are respectively disposed on two second positive electrode grid line arrays. The second positive electrode welding portions are connected to the second positive electrode grid line in the second positive electrode grid line array that is closest to the first positive electrode grid line array. Each column of negative electrode welding portions includes multiple first negative electrode welding portions and two second negative electrode welding portions. The multiple first negative electrode welding portions are respectively disposed on multiple first negative electrode grid lines, and the two second negative electrode welding portions are respectively disposed on two second negative electrode grid line arrays. The second negative electrode welding portions are connected to the second negative electrode grid line in the second negative electrode grid line array that is closest to the first negative electrode grid line array.
5. The solar cell according to claim 4, characterized in that, Each second positive gate line includes multiple positive sub-gate lines spaced apart in the second direction, and each second negative gate line includes multiple negative sub-gate lines spaced apart in the second direction; At least a portion of the second positive electrode welding portion is connected to a plurality of positive electrode sub-grid lines belonging to different second positive electrode grid lines, and at least a portion of the second negative electrode welding portion is connected to a plurality of negative electrode sub-grid lines belonging to different second negative electrode grid lines.
6. The solar cell according to claim 3, characterized in that, The two ends of the positive electrode connection line are respectively connected to the ends of the two adjacent first positive electrode grid lines; the two ends of the negative electrode connection line are respectively connected to the ends of the two adjacent first negative electrode grid lines.
7. The solar cell according to claim 3, characterized in that, The positive electrode connection line is connected to the ends of all the first positive electrode grid lines, and the negative electrode connection line is connected to the ends of all the first negative electrode grid lines.
8. The solar cell according to claim 3, characterized in that, The connection point between the positive busbar and the second positive busbar furthest from the first positive busbar array is chamfered; the connection point between the negative busbar and the second negative busbar furthest from the first negative busbar array is chamfered.
9. The solar cell according to claim 3, characterized in that, The spacing between two adjacent first positive gate lines is X1, and the spacing between the end of the first negative gate line closest to the positive connection line and the positive connection line in the second direction is D1, where D1 / X1 is 0.1~0.
3. The spacing between two adjacent first negative gate lines is X2, and the spacing between the end of the first positive gate line near the negative connection line and the negative connection line in the second direction is D2, where D2 / X2 is 0.1~0.
3.
10. A photovoltaic module, characterized in that, The solar cell includes any one of claims 1-9.