Silicon solar cell and method for manufacturing the same

Abstract

The present invention discloses a silicon solar cell and a manufacturing method thereof, wherein the silicon solar cell comprises a plurality of cell slices and a plurality of welding strips, wherein the cell slices are provided with through holes, and adjacent cell slices are connected by welding strips, the welding strips pass through the through holes, and the two ends of the welding strips are respectively welded to the front and back sides of two adjacent cell slices, that is, one end of the welding strip is welded to the front side of one of the cell slices, and the other end of the welding strip is welded to the back side of another adjacent cell slice. The present invention greatly reduces the cell spacing between cell slices, so that more cells can be placed under the same area, increasing the power of the cell assembly, and avoiding the height difference between two adjacent cell slices, effectively preventing the welding strips from being squeezed on the cell edge by external force to cause hidden cracks.

Description

Technical Field

[0001] The present invention relates to the field of solar cells, and more particularly to a silicon solar cell sheet and a manufacturing method thereof. Background Art

[0002] Solar cell power generation is an environmentally friendly way of generating electricity. The power generation process does not produce greenhouse gases such as carbon dioxide and does not pollute the environment. At present, solar cells made of crystalline silicon are the mainstream of the industry.

[0003] The conventional existing cell laser cutting methods are to cut the cell in half or cut into large and small pieces perpendicular to the main grid line, and then the cut cells are welded in series to make photovoltaic modules. During the string welding process, the cells cut by laser in this way must maintain a certain spacing between the slices to prevent the welding ribbon from being unable to bend and causing a height difference in the cell, and then prevent the welding ribbon from squeezing the edge of the cell due to external force and causing hidden cracks. However, the larger spacing between the slices means that the number of cells that can be placed per unit area is small, which is not conducive to increasing the power of the module.

[0004] In addition, during the existing processing, when the main grid lines of the battery cell are opened, due to process limitations, the fine grid lines around the main grid lines are often disconnected from the main grid lines, resulting in the inability to collect current. In this case, the battery cell often cannot generate electricity normally, and even causes serious internal consumption of the battery cell, resulting in power loss.

[0005] In summary, the art urgently needs a new solar cell and a manufacturing method thereof to solve the above problems. Summary of the invention

[0006] An object of the present invention is to provide a silicon solar cell and a method for manufacturing the same, which greatly reduces the spacing between cell slices, so that more cells can be placed in the same area, thereby increasing the power of the cell assembly.

[0007] Another object of the present invention is to provide a silicon solar cell and a method for manufacturing the same, which avoids the height difference between two adjacent cell slices and effectively prevents the soldering tape from being squeezed on the cell edge by external force and causing hidden cracks.

[0008] Another object of the present invention is to provide a silicon solar cell and a method for manufacturing the same, which avoids the situation where the thin grid lines are broken due to the presence of holes, thereby reducing power loss.

[0009] According to one aspect of the present invention, the present invention provides a silicon solar cell, comprising:

[0010] A plurality of battery cell slices and a plurality of welding strips, wherein the battery cell slices are provided with through holes, adjacent battery cell slices are connected by the welding strips, the welding strips pass through the through holes, and the two ends thereof are respectively welded to the front and back sides of two adjacent battery cell slices, one end of the welding strip is welded to the front side of the battery cell slice, and the other end of the welding strip is welded to the back side of the adjacent battery cell slice.

[0011] The welding ribbon is bent in a "Z" shape at the through hole. Through such a design, the distance between two adjacent battery cell slices is greatly reduced, so that more battery cells can be placed in the same area, thereby increasing the power of the battery cell assembly; at the same time, the height difference between two adjacent battery cell slices is avoided, effectively preventing the welding ribbon from being squeezed on the edge of the battery cell by external force and causing hidden cracks.

[0012] According to a preferred embodiment of the present invention, the solar cell slice is provided with main grid lines and thin grid lines perpendicular to each other, the through holes are arranged along the direction of the main grid lines, and the welding position of the welding strip coincides with the main grid lines.

[0013] According to a preferred embodiment of the present invention, the fine gate lines outside the through hole are connected to each other, thereby preventing the fine gate lines from being broken due to the presence of the hole, thereby reducing power loss.

[0014] Preferably, the through hole is located at the edge of the battery cell slice.

[0015] According to another aspect of the present invention, the present invention further provides a method for manufacturing a silicon solar cell, which comprises the following steps:

[0016] (S1) providing a plurality of original silicon wafers, and cutting holes in the original silicon wafers to form through holes;

[0017] (S2) screen printing the original silicon wafer to obtain a battery cell, and forming mutually perpendicular main grid lines and fine grid lines on the original silicon wafer, wherein the fine grid lines outside the through hole are connected to each other;

[0018] (S3) slicing the battery cell to obtain a plurality of battery cell slices;

[0019] (S4) A soldering tape is arranged to pass through the through hole, one end of the soldering tape is soldered to the front side of the battery cell slice, and the other end of the soldering tape is soldered to the back side of an adjacent battery cell slice.

[0020] Preferably, the welding position of the welding strip coincides with the main grid line.

[0021] Preferably, the through hole is formed by laser cutting.

[0022] Preferably, the through hole is located at the edge of the battery cell slice.

[0023] The above and other objects, features and advantages of the present invention will be further clarified through the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the original silicon wafer after hole cutting;

[0025] Figure 2 This is a schematic diagram of the original silicon wafer after screen printing;

[0026] Figure 3 This is a partial enlarged schematic diagram of the original silicon wafer after screen printing;

[0027] Figure 4 It is a schematic diagram of cell slices;

[0028] Figure 5 It is a schematic diagram of welding the cell slices and the welding ribbon;

[0029] Figure 6 It is a schematic diagram of two battery cell slices connected by welding ribbon;

[0030] Figure 7 It is an enlarged schematic diagram of two battery cell slices connected by welding ribbons;

[0031] Figure 8 is a schematic flow chart of a method for manufacturing a silicon solar cell according to a preferred embodiment of the present invention;

[0032] In the figure: a cell slice 10; a through hole 11; a main grid line 12; a thin grid line 13; a welding strip 20; and an original silicon wafer 30. DETAILED DESCRIPTION

[0033] The invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0034] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0035] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0036] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0037] See attached picture Figures 1 to 8 The silicon solar cell and its manufacturing method according to the preferred embodiment of the present invention will be explained in the following description. Figure 3 To Attachment Figure 7 As shown, the silicon solar cell comprises a plurality of cell slices 10 and a plurality of welding strips 20 , and adjacent cell slices 10 are connected by the welding strips 20 .

[0038] Specifically, the cell slice 10 is provided with a through hole 11, and the soldering ribbon 20 passes through the through hole 11. Figure 5 To Attachment Figure 7 The two ends of the welding tape 20 are respectively welded to the front and back sides of the two adjacent battery cell slices 10. In other words, one end of the welding tape 20 is welded to the front side of the battery cell slice 10, and the other end of the welding tape 20 is welded to the back side of the adjacent battery cell slice 10. Figure 7 As shown, the distance between two adjacent battery cell slices 10 is approximately zero, and the two battery cell slices 10 are in the same plane.

[0039] During the string welding process, the welding ribbon 20 can be bent in a "Z" shape at the through hole 11. Through such a design, the spacing between two adjacent battery cell slices 10 is greatly reduced, so that more battery cells can be placed in the same area, thereby increasing the power of the battery cell assembly; at the same time, the height difference between two adjacent battery cell slices 10 is avoided, effectively preventing the welding ribbon 20 from being squeezed and cracked on the edge of the battery cell due to external force.

[0040] It is easy for those skilled in the art to understand that the shape of the through hole 11 is not limited in the present invention. In this embodiment, the shape of the through hole 11 is a quadrilateral as an example to illustrate and disclose the content and features of the battery cell slice 10 of the present invention. In other possible preferred embodiments, the shape of the through hole 11 can also be but not limited to a triangle, a circle, an ellipse, etc.

[0041] From the attached Figure 4 It can be seen that, preferably, the through hole 11 is located at the edge of the battery cell slice 10 .

[0042] Furthermore, the cell slice 10 is provided with mutually perpendicular main grid lines 12 and thin grid lines 13. Preferably, the through holes 11 are arranged along the main grid lines 12, and the welding position of the welding strip 20 coincides with the main grid lines 12.

[0043] It is worth mentioning that Figure 3 As shown, the fine gate lines 13 outside the through hole 11 are connected to each other, which avoids the situation where the fine gate lines 13 are broken due to the existence of the hole, thereby reducing power loss.

[0044] See the attached Figure 1 , Attachment Figure 2 , and attached Figure 8 The present invention further provides a method for manufacturing a silicon solar cell, which comprises the following steps:

[0045] (S1) providing a plurality of original silicon wafers 30, and cutting holes in the original silicon wafers 30 to form through holes 11;

[0046] (S2) screen printing the original silicon wafer 30 to obtain a solar cell, and forming mutually perpendicular main grid lines 12 and fine grid lines 13 on the original silicon wafer 30, wherein the fine grid lines 13 outside the through hole 11 are connected to each other;

[0047] (S3) Slicing the battery cell to obtain a plurality of battery cell slices 10;

[0048] (S4) A soldering ribbon 20 is arranged to pass through the through hole 11 , one end of the soldering ribbon 20 is welded to the front side of the battery cell slice 10 , and the other end of the soldering ribbon 20 is welded to the back side of the adjacent battery cell slice 10 .

[0049] In the step (S1), preferably, the through hole 11 is formed by laser cutting to reduce the phenomenon that the residue generated during cutting of the printed cell is not easy to fall off, and laser cutting reduces the damage to the PN junction of the cell.

[0050] See attached Figure 2 and attached Figure 3The fine grid lines 13 around the through holes 11 of the cell after screen printing are connected to each other, which can avoid the power loss of the cell caused by the broken grid of the fine grid lines 13.

[0051] Preferably, the welding position of the welding strip 20 coincides with the main grid line 12 .

[0052] It should be understood by those skilled in the art that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A silicon solar cell, characterized in that: include: A plurality of battery cell slices and a plurality of welding strips, wherein the battery cell slices are provided with through holes, adjacent battery cell slices are connected by the welding strips, the welding strips pass through the through holes, and the two ends of the welding strips are respectively welded to the front and back sides of two adjacent battery cell slices, one end of the welding strip is welded to the front side of the battery cell slice, and the other end of the welding strip is welded to the back side of the adjacent battery cell slice; The cell slice is provided with main grid lines and thin grid lines perpendicular to each other, the through holes are arranged along the direction of the main grid lines, and the welding position of the welding strip coincides with the main grid lines; The fine grid lines outside the through hole are connected to each other.

2. The silicon solar cell according to claim 1, characterized in that: The through hole is located at the edge of the battery cell slice.

3. A method for manufacturing a silicon solar cell, characterized in that: The following steps are involved: (S1) providing a plurality of original silicon wafers, and cutting holes in the original silicon wafers to form through holes; (S2) screen printing the original silicon wafer to obtain a battery cell, and forming mutually perpendicular main grid lines and fine grid lines on the original silicon wafer, wherein the fine grid lines outside the through hole are connected to each other; (S3) slicing the battery cell to obtain a plurality of battery cell slices; (S4) A soldering tape is arranged to pass through the through hole, one end of the soldering tape is soldered to the front side of the battery cell slice, and the other end of the soldering tape is soldered to the back side of an adjacent battery cell slice.

4. The method for manufacturing a silicon solar cell according to claim 3, characterized in that: The welding position of the welding strip coincides with the main grid line.

5. The method for manufacturing a silicon solar cell according to claim 3, characterized in that: The through holes are formed by laser cutting.

6. The method for manufacturing a silicon solar cell according to claim 3, characterized in that: The through hole is located at the edge of the battery cell slice.

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