Solar cell and photovoltaic module

Abstract

The utility model relates to a solar cell and a photovoltaic module. The solar battery comprises a battery piece and a welding wire, a plurality of grid lines arranged in parallel are arranged on the surface of the battery piece, the welding wire extends in the direction perpendicular to the grid lines and intersects with all the grid lines, and glue points are arranged between the welding wire and the battery piece and used for bonding and fixing the welding wire and the battery piece. Wherein the length L of the glue point in the direction perpendicular to the extending direction of the welding wire and the diameter d of the welding wire meet the condition that L is larger than or equal to d + 0.6 mm; and the height H of the glue points is between 1 / 3d and d. According to the solar cell and the photovoltaic module, the shapes and sizes of the glue points in series welding are definitely limited, and the problems that when glue is too much, the appearance of the photovoltaic module is poor, such as white points or bubbles, and when glue is insufficient, virtual connection of a cell string is prone to occurring are solved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to solar cells and photovoltaic modules. Background Art

[0002] In the photovoltaic industry, single-cell batteries cannot be used directly as power sources due to their fragility and poor aging resistance. Multiple cells need to be connected in series and parallel using welding wires to form a battery string, which then needs to be laid out, stacked, and packaged to form a photovoltaic module before it can be used for a long time.

[0003] Continuous innovation in solar cell technology has shifted from SMBB (super multi-busbar) to 0BB (no busbar) technology. 0BB cells, due to their busbar-free design, can reduce silver paste usage, thereby reducing costs and improving production efficiency. In 0BB cells, the wire is typically secured to the cell by applying glue between the wire and the cell. Currently, screen printing is commonly used to apply the glue to the cell, but there are no strict requirements for the glue's appearance and size. Excessive glue can lead to cosmetic issues such as white spots in photovoltaic modules after lamination, affecting power efficiency. Insufficient glue can lead to unstable wire connections and poor connections in the cell strings. Utility Model Content

[0004] Based on this, it is necessary to provide a solar cell and photovoltaic module, which clearly defines the shape and size of the glue points in the string welding, and solves the problems of poor appearance such as white spots or bubbles on the photovoltaic modules caused by excessive glue, and the problems of poor connection of the battery strings caused by insufficient glue.

[0005] In a first aspect, the present application provides a solar cell, comprising:

[0006] A cell, wherein a surface of the cell is provided with a plurality of parallel grid lines; and

[0007] A welding wire extending in a direction perpendicular to the grid lines and intersecting all the grid lines, with glue points provided between the welding wire and the battery cell;

[0008] The length L of the glue spot in the direction perpendicular to the extension direction of the welding wire and the diameter d of the welding wire satisfy: L≥d+0.6mm; the height H of the glue spot is between 1 / 3d and d.

[0009] By configuring the relationship between the length L of the glue point and the diameter d of the welding wire to be L ≥ d + 0.6 mm, the aforementioned solar cell fully considers the influence of the welding wire layout accuracy and the glue printing accuracy. This prevents the welding wire and the glue point from shifting left and right during layout, which could result in the welding wire not being able to adhere stably to the glue point, thereby avoiding the phenomenon of a loose connection in the cell string. In addition, by configuring the height H of the glue point to be between 1 / 3 d and d, on the one hand, sufficient contact area is ensured between the glue point and the welding wire, so that the welding wire can withstand sufficient tensile force, preventing the phenomenon of a loose connection in the cell string caused by the welding wire falling off. On the other hand, it also avoids the appearance of poor appearance such as white spots or bubbles in the photovoltaic module after lamination due to the glue point protruding from the welding wire, thereby ensuring the efficiency of the photovoltaic module.

[0010] The technical solution is further described below:

[0011] In one embodiment, the shape of the glue dots is oval or rectangular.

[0012] In one embodiment, the diameter d of the welding wire ranges from 0.1 mm to 0.3 mm.

[0013] In one embodiment, the width D of the glue dot in the extension direction of the welding wire is 0.2 mm-0.6 mm.

[0014] In one embodiment, the weight of each glue dot is 0.05mg-0.08mg.

[0015] In one embodiment, there are multiple welding wires, and the welding wires are spaced apart along the extending direction of the grid lines.

[0016] In one embodiment, the length L of the glue spot is smaller than the distance between two adjacent welding wires.

[0017] In one embodiment, a plurality of glue points are provided between the welding wire and the battery cell, and the glue points are spaced apart along the extension direction of the welding wire.

[0018] In one embodiment, the glue dots are arranged between two adjacent grid lines.

[0019] In a second aspect, the present application also provides a photovoltaic module comprising the above-mentioned solar cell.

[0020] In the above-mentioned photovoltaic module, the solar cell fully considers the influence of the placement accuracy of the welding wire and the glue printing accuracy by configuring the relationship between the length L of the glue point and the diameter d of the welding wire to be L ≥ d + 0.6 mm. This prevents the welding wire and the glue point from being offset left and right during placement, which would result in the welding wire not being able to adhere stably to the glue point, thereby avoiding the phenomenon of false connection in the battery string. In addition, by configuring the height H of the glue point to be between 1 / 3 d and d, on the one hand, sufficient contact area is ensured between the glue point and the welding wire, so that the welding wire can withstand sufficient tensile force, preventing the phenomenon of false connection in the battery string caused by the welding wire falling off, and on the other hand, it also avoids the appearance of poor appearance such as white spots or bubbles in the photovoltaic module after lamination due to the glue point protruding from the welding wire, thereby ensuring the efficiency of the photovoltaic module. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings that constitute a part of this application are used to provide further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute improper limitations on this application.

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] In addition, the drawings are not drawn to a 1:1 scale, and the relative sizes of the various elements are drawn only for illustrative purposes and are not necessarily drawn to true scale.

[0024] Figure 1 Schematic diagram of the structure of a solar cell according to an embodiment.

[0025] Figure 2 for Figure 1 Side view of the solar cell shown in .

[0026] Figure 3 for Figure 1 A partial enlarged view of the solar cell shown in FIG.

[0027] Figure 4 for Figure 2 A partial enlarged view of the solar cell shown in part B.

[0028] Description of reference numerals:

[0029] 10. Battery cell; 11. Grid line; 20. Welding wire; 30. Glue point. DETAILED DESCRIPTION

[0030] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0031] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0032] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0033] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0034] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0035] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0036] An embodiment of the present application provides a solar cell, specifically, see Figure 1 as well as Figure 2 The solar cell of one embodiment includes a cell 10 and a welding wire 20. The surface of the cell 10 is provided with a plurality of parallel grid lines 11. The welding wire 20 extends in a direction perpendicular to the grid lines 11 and intersects with all the grid lines 11. A glue point 30 is provided between the welding wire 20 and the cell 10. The glue point 30 is used to bond and fix the welding wire 20 and the cell 10. Figure 3 as well as Figure 4 , wherein the length L of the glue point 30 in the direction perpendicular to the extension direction of the welding wire 20 and the diameter d of the welding wire 20 satisfy: L≥d+0.6mm; the height H of the glue point 30 is between 1 / 3d and d, and the height H of the glue point 30 refers to the size of the glue point 30 in the thickness direction of the battery cell 10.

[0037] Specifically, through creative work, the inventors discovered that to ensure a stable connection between the welding wire 20 and the glue dots 30, it is necessary to fully consider the left-right offset of the welding wire 20 and the glue dots 30 during layout. Therefore, the length L of the glue dots 30 must satisfy L ≥ d + 2* (layout accuracy of the welding wire 20 + printing accuracy of the glue dots 30). The layout accuracy of the welding wire 20 depends on the accuracy of the equipment used to pull the welding wire 20, which currently has a minimum accuracy of 0.2 mm. The printing accuracy of the glue dots 30 depends on the accuracy of the screen printing equipment, which currently generally has a minimum accuracy of 0.1 mm. Therefore, L ≥ d + 2* (layout accuracy of the welding wire 20 + printing accuracy of the glue dots 30) = d + 2* (0.2 + 0.1) = d + 0.6 mm.

[0038] Furthermore, if the height H of the glue dot 30 is less than 1 / 3d, the contact area between the glue dot 30 and the welding wire 20 is too small, which can easily lead to insufficient adhesion between the welding wire 20 and the glue dot 30, and the welding wire 20 can not withstand enough tension, so the welding wire 20 is easy to fall off, resulting in a false connection in the battery string. If the height H of the glue dot 30 is greater than d, the glue dot 30 will protrude from the welding wire 20. In subsequent processes, the glue dot 30 will scrape against the conveyor belt, causing the undried glue dot 30 to deform or stick to the conveyor belt. The glue dot 30 stuck on the conveyor belt will contaminate the subsequent battery cells 10, causing the contaminated battery cells 10 to have white spots and other appearance problems after lamination. In addition, when the height H of the glue dot 30 is greater than d, there is too much glue. When the welding wire 20 is placed in the glue dot 30, bubbles are easily formed in the glue dot 30, which in turn causes obvious bubbles in the photovoltaic module after lamination, affecting the efficiency of the photovoltaic module.

[0039] In summary, the above-mentioned solar cell fully considers the influence of the placement accuracy of the welding wire 20 and the printing accuracy of the glue dot 30 by configuring the relationship between the length L of the glue dot 30 and the diameter d of the welding wire 20 to be L≥d+0.6mm, thereby preventing the welding wire 20 and the glue dot 30 from being offset left and right during placement, which would cause the welding wire 20 to be unable to be stably bonded to the glue dot 30, thereby avoiding the phenomenon of false connection in the battery string. In addition, by configuring the height H of the glue dot 30 to be between 1 / 3d and d, on the one hand, sufficient contact area is ensured between the glue dot 30 and the welding wire 20, so that the welding wire 20 can withstand sufficient tensile force, preventing the welding wire 20 from falling off and causing the battery string to have a false connection. On the other hand, it also avoids the appearance problems such as white spots or bubbles in the photovoltaic module after lamination caused by the glue dot 30 protruding from the welding wire 20, thereby ensuring the efficiency of the photovoltaic module.

[0040] See also Figure 3 In one embodiment, the shape of the glue dots 30 is oval or rectangular. The oval or rectangular glue dots 30 are made of a printing screen with a simple opening structure and a mature printing process, which can effectively improve production efficiency.

[0041] Optionally, in one embodiment, the diameter d of the welding wire 20 ranges from 0.1 mm to 0.3 mm, such as 0.1 mm, 0.15 mm, 0.18 mm, 0.2 mm, 2.3 mm, 2.5 mm, or 0.3 mm. Specifically, if the diameter d of the welding wire 20 is less than 0.1 mm, the current carrying capacity of the welding wire 20 is insufficient, affecting current collection. If the diameter d of the welding wire 20 is greater than 0.3 mm, the material cost of the welding wire 20 increases. By configuring the diameter d of the welding wire 20 to be between 0.1 mm and 0.3 mm, the current carrying capacity of the welding wire 20 is met while effectively controlling costs.

[0042] See also Figure 3Optionally, in one embodiment, the width D of the glue dot 30 in the extension direction of the welding wire 20 is 0.2 mm to 0.6 mm, for example, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, or 0.6 mm. Specifically, if the width D of the glue dot 30 is less than 0.2 mm, the contact area between the glue dot 30 and the welding wire 20 is too small, which can easily lead to insufficient adhesion between the welding wire 20 and the glue dot 30, and the welding wire 20 can easily fall off, resulting in a poor connection in the battery string. If the width D of the glue dot 30 is greater than 0.6 mm, the amount of glue in the glue dot 30 is too much, which not only increases the cost but also makes it difficult for the undried glue dot 30 to maintain a stable shape. Therefore, by configuring the width D of the glue dot 30 to be 0.2 mm to 0.6 mm, it is possible to ensure that the glue dot 30 can be stably connected to the welding wire 20, effectively control costs, and help the glue dot 30 maintain a stable shape.

[0043] Optionally, in one embodiment, the weight of a single glue dot 30 is 0.05 mg to 0.08 mg, for example, 0.05 mg, 0.06 mg, 0.07 mg, or 0.08 mg. The weight of a single glue dot 30 refers to the weight of the glue consumed by a single glue dot 30. By setting the weight of a single glue dot 30 to 0.05 mg to 0.08 mg, the amount of glue consumed by a single glue dot 30 can be effectively controlled, effectively controlling costs while ensuring a stable connection between the glue dot 30 and the welding wire 20.

[0044] See also Figure 1 In one embodiment, there are multiple welding wires 20, each of which is spaced apart along the extending direction of the grid lines 11. By providing multiple welding wires 20, the flow capacity between the two solar cells 10 can be increased, thereby improving the efficiency of the photovoltaic module.

[0045] Furthermore, the length L of the glue dots 30 is less than the spacing between two adjacent welding wires 20. In this way, overlapping between two adjacent glue dots 30 in the extending direction of the grid lines 11 is avoided, thereby avoiding glue waste and reducing costs.

[0046] See also Figure 1 In one embodiment, multiple adhesive points 30 are provided between the welding wire 20 and the battery cell 10, for example, two, three, four, five, or six or more. The adhesive points 30 are spaced apart along the extension direction of the welding wire 20. This increases the number of connection points between the welding wire 20 and the battery cell 10, thereby improving the stability of the connection between the welding wire 20 and the battery cell 10.

[0047] Optionally, the glue dots 30 are arranged between two adjacent grid lines 11 , so as to avoid the glue dots 30 covering the grid lines 11 and prevent poor contact between the grid lines 11 and the welding wire 20 , thereby ensuring the flow capacity between the grid lines 11 and the welding wire 20 .

[0048] Another embodiment of the present application further provides a photovoltaic module. Specifically, the photovoltaic module of one embodiment includes the above-mentioned solar cell. Further, the photovoltaic module includes multiple solar cells 10, and the welding wire 20 connects two adjacent solar cells 10.

[0049] In the above-mentioned photovoltaic module, the solar cell fully considers the influence of the placement accuracy of the welding wire 20 and the printing accuracy of the glue dot 30 by configuring the relationship between the length L of the glue dot 30 and the diameter d of the welding wire 20 to be L≥d+0.6mm. This prevents the welding wire 20 and the glue dot 30 from being offset left and right during placement, which would result in the welding wire 20 not being able to be stably bonded to the glue dot 30, thereby avoiding the phenomenon of a poor connection in the cell string. In addition, by configuring the height H of the glue dot 30 to be between 1 / 3d and d, on the one hand, sufficient contact area is ensured between the glue dot 30 and the welding wire 20, so that the welding wire 20 can withstand sufficient tensile force, thereby preventing the welding wire 20 from falling off and causing a poor connection in the cell string. On the other hand, it also avoids the appearance of white spots or bubbles in the photovoltaic module after lamination due to the glue dot 30 protruding from the welding wire 20, thereby ensuring the efficiency of the photovoltaic module.

[0050] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A solar cell, characterized in that: include: A battery cell (10), wherein a surface of the battery cell (10) is provided with a plurality of parallel grid lines (11); and a welding wire (20), the welding wire (20) extending in a direction perpendicular to the grid lines (11) and intersecting all the grid lines (11), and a glue point (30) being provided between the welding wire (20) and the battery cell (10); The length L of the glue point (30) in the extension direction perpendicular to the welding wire (20) and the diameter d of the welding wire (20) satisfy the following conditions: L≥d+0.6mm; and the height H of the glue point (30) is between 1 / 3d and d.

2. The solar cell according to claim 1, characterized in that The shape of the glue dots (30) is oval or rectangular.

3. The solar cell according to claim 1, wherein The diameter d of the welding wire (20) ranges from 0.1 mm to 0.3 mm.

4. The solar cell according to claim 1, wherein The width D of the glue point (30) in the extension direction of the welding wire (20) is 0.2 mm to 0.6 mm.

5. The solar cell according to claim 1, wherein The unit weight of the glue point (30) is 0.05mg-0.08mg.

6. The solar cell according to claim 1, wherein There are a plurality of welding wires (20), and each welding wire (20) is arranged at intervals along the extending direction of the grid line (11).

7. The solar cell according to claim 1, wherein The length L of the glue point (30) is smaller than the distance between two adjacent welding wires (20).

8. The solar cell according to claim 1, wherein A plurality of glue points (30) are provided between the welding wire (20) and the battery cell (10), and the glue points (30) are arranged at intervals along the extension direction of the welding wire (20).

9. The solar cell according to claim 1, wherein The glue dots (30) are arranged between two adjacent grid lines (11).

10. A photovoltaic module, characterized in that: The solar cell comprises the solar cell according to any one of claims 1 to 9.

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