CN-122028547-A - Back contact battery, battery assembly and photovoltaic system

Abstract

The application relates to the technical field of solar cells, and provides a back contact cell, a cell assembly and a photovoltaic system, wherein a plurality of anti-breaking grid line groups comprising a first anti-breaking grid line and a second anti-breaking grid line are arranged on the back contact cell, the arrangement of the anti-breaking grid line group can reduce the fracture risk of the first fine grid and the second fine grid, and further effectively ensure the collection effect of carriers so as to ensure the efficiency of the back contact battery. Meanwhile, as the first welding part and the second welding part are not arranged between the two anti-breaking grid lines in the anti-breaking grid line group in the back contact battery, the path of collecting carriers by the back contact battery is more balanced, and meanwhile, the short circuit risk caused by the fact that the welding belt contacts the anti-breaking grid lines with different polarities can be reduced.

Inventors

• WANG YONGQIAN
• ZHAO XIN

Assignees

• 浙江爱旭太阳能科技有限公司
• 天津爱旭太阳能科技有限公司
• 珠海富山爱旭太阳能科技有限公司
• 山东爱旭太阳能科技有限公司

Dates

Publication Date

20260512

Application Date

20251231

Claims (20)

1. 1. A back contact battery, comprising: a silicon substrate having opposite front and back surfaces; a plurality of first fine grids and a plurality of second fine grids which are arranged on the back surface and extend along a first direction, the plurality of first fine grids and the plurality of second fine grids are alternately arranged at intervals along a second direction, the second direction intersects with the first direction, and The anti-breaking grid line groups are arranged on the back surface and are arranged at intervals along the first direction, each anti-breaking grid line group comprises a first anti-breaking grid line and a second anti-breaking grid line which are arranged at intervals along the first direction, each first anti-breaking grid line is connected with at least two first thin grids, each second anti-breaking grid line is connected with at least two second thin grids, each first thin grid is interrupted at the corresponding second anti-breaking grid line, and each second thin grid is interrupted at the corresponding first anti-breaking grid line; At least part of the first thin grids are provided with first welding parts between two adjacent anti-breaking grid line groups, at least part of the second thin grids are provided with second welding parts between two adjacent anti-breaking grid line groups, the second welding parts are spaced from the first welding parts in the first direction, the first welding parts and the second welding parts are used for welding with welding strips, the first thin grids are not provided with the first welding parts between the first anti-breaking grid line and the second anti-breaking grid line, and the second thin grids are not provided with the second welding parts between the first anti-breaking grid line and the second anti-breaking grid line.
2. 2. The back contact battery of claim 1, wherein in the anti-break grid line group, a spacing between the first anti-break grid line and the second anti-break grid line is 0.1mm-12mm.
3. 3. The back contact battery of claim 2, wherein in the anti-break grid line group, a spacing between the first anti-break grid line and the second anti-break grid line is 0.1mm-5mm.
4. 4. The back contact battery of claim 1, wherein a spacing between adjacent first and second welds is 0.5mm-20mm.
5. 5. The back contact battery of claim 4, wherein a spacing between adjacent first and second welds is 2mm-15mm.
6. 6. The back contact battery of claim 1, wherein said first thin grid has at least one of said first welds between adjacent two of said break preventing grid lines and said second thin grid has at least one of said second welds between adjacent two of said break preventing grid lines.
7. 7. The back contact battery of claim 1, wherein the first thin grid has only one of the first welds between adjacent two of the break resistant grid line sets and the second thin grid has only one of the second welds between adjacent two of the break resistant grid line sets; The distance between two adjacent anti-breaking grid line groups is L1, and the distance between the first welding part and the second welding part between two adjacent anti-breaking grid line groups is L2, wherein L1/L2 is more than or equal to 1.2 and less than or equal to 10.
8. 8. The back contact battery of claim 1, wherein the first and second break preventing grids of two adjacent break preventing grids are arranged in the same manner, wherein the first break preventing grid of one of the break preventing grids is adjacent to the second break preventing grid of the other break preventing grid.
9. 9. The back contact battery of claim 8, wherein said first thin grid has only one of said first welds between adjacent two of said break preventing grid lines and said second thin grid has only one of said second welds between adjacent two of said break preventing grid lines; The first fine grid comprises first grid line segments positioned between adjacent anti-breaking grid line groups, the first grid line segments comprise first welding parts, first parts positioned between the first welding parts and the first anti-breaking grid lines in one anti-breaking grid line group and second parts positioned between the first welding parts and the second anti-breaking grid lines in the other anti-breaking grid line group, and the length of the first parts is larger than that of the second parts; The second fine grid comprises second grid line segments positioned between adjacent anti-breaking grid line groups, the second grid line segments comprise second welding parts, third parts positioned between the second welding parts and the second anti-breaking grid lines of one anti-breaking grid line group and fourth parts positioned between the second welding parts and the first anti-breaking grid lines of the other anti-breaking grid line group, and the length of the third parts is larger than that of the fourth parts.
10. 10. The back contact battery of claim 1, wherein the spacing between two adjacent first break preventing grids is 5mm-25mm, and/or The distance between two adjacent second anti-breaking grid lines is 5mm-25mm.
11. 11. The back contact battery of claim 10, wherein a ratio between a spacing between adjacent two of the first break preventing gate lines and a length of the silicon substrate in the first direction is 0.025-0.125, and/or The ratio of the distance between two adjacent second anti-breaking grid lines to the length of the silicon substrate in the first direction is 0.025-0.125.
12. 12. The back contact battery of claim 1, wherein the first break preventing grid line is a continuous structure and extends continuously along the second direction, the first break preventing grid line connects all of the first thin grids, the second thin grid line is discontinuous at the first break preventing grid line, and/or The second anti-breaking grid lines are of continuous structures and extend continuously along the second direction, the second anti-breaking grid lines are connected with all the second fine grids, and the first fine grids are discontinuous at the second anti-breaking grid lines.
13. 13. The back contact battery of claim 12, wherein the width of the first break preventing grid line is greater than or equal to the width of the first fine grid, and/or The width of the second anti-breaking grid line is larger than or equal to that of the second fine grid.
14. 14. The back contact battery of claim 1, wherein the first break preventing grid line is of an intermittent structure and comprises a plurality of first connecting sections arranged at intervals along the second direction, and each first connecting section is connected with at least two first thin grids; the second thin grid is arranged between two adjacent first connecting sections, and the second thin grid between two adjacent first connecting sections is discontinuous or continuous at the interval between two adjacent first connecting sections.
15. 15. The back contact battery of claim 14, wherein the width of the first connection section is greater than or equal to the width of the first fine grid.
16. 16. The back contact battery of claim 1, wherein the second anti-breakage grid line is of an intermittent structure and comprises a plurality of second connection sections arranged at intervals along the second direction, and each second connection section is connected with at least two second thin grids; The first thin grid is arranged between two adjacent second connecting sections, and the first thin grid between two adjacent second connecting sections is discontinuous or continuous at the interval of the two adjacent second connecting sections.
17. 17. The back contact battery of claim 16, wherein the width of the second connection section is greater than or equal to the width of the second fine grid.
18. 18. The back contact battery of claim 1, wherein the first anti-breakage gate line is of a discontinuous structure and comprises a plurality of first connection sections arranged at intervals along the second direction, one second fine gate is arranged between two adjacent first connection sections, the second anti-breakage gate line is of a discontinuous structure and comprises a plurality of second connection sections arranged at intervals along the second direction, and one first fine gate is arranged between two adjacent second connection sections; In the anti-breaking grid unit, the first connecting section is connected with two adjacent first thin grids, the first connecting section corresponds to one second thin grid, the second connecting section is connected with two adjacent second thin grids, one of the second thin grids connected with the second connecting section is the second thin grid corresponding to the first connecting section, and the other second thin grid connected with the second connecting section is the second thin grid located between the two adjacent first connecting sections.
19. 19. The back contact battery of claim 1, wherein the first break preventing grid line is connected to all of the first fine grids and the second break preventing grid line is connected to all of the second fine grids.
20. 20. The back contact battery of claim 1, wherein the second fine grid is intermittently formed at the first break preventing grid line with a spacing of 0.2mm to 5mm between an end point and the first break preventing grid line, and/or The interval between the end point formed by the first fine grid at the position of the second anti-breaking grid line in a discontinuous mode and the second anti-breaking grid line is 0.2mm-5mm.

Description

Back contact battery, battery assembly and photovoltaic system Technical Field The application relates to the technical field of solar cells, in particular to a back contact cell, a cell assembly and a photovoltaic system. Background Solar cell power generation is a sustainable clean energy source that uses the photovoltaic effect of the semiconductor P-N junction to convert sunlight into electrical energy. In the related art, in the back contact battery, the grid lines with two polarities are both arranged on the back of the battery so as to reduce the shielding of light when the grid lines are arranged on the front of the battery. However, the risk of gate breakage of the back contact cell is large, resulting in poor carrier collection effect of the back contact cell, thereby affecting the efficiency of the back contact cell. Disclosure of Invention The application provides a back contact battery, a battery assembly and a photovoltaic system. The application is realized in such a way that the back contact battery of the embodiment of the application comprises: a silicon substrate having opposite front and back surfaces; a plurality of first fine grids and a plurality of second fine grids which are arranged on the back surface and extend along a first direction, the plurality of first fine grids and the plurality of second fine grids are alternately arranged at intervals along a second direction, the second direction intersects with the first direction, and The anti-breaking grid line groups are arranged on the back surface and are arranged at intervals along the first direction, each anti-breaking grid line group comprises a first anti-breaking grid line and a second anti-breaking grid line which are arranged at intervals along the first direction, each first anti-breaking grid line is connected with at least two first thin grids, each second anti-breaking grid line is connected with at least two second thin grids, each first thin grid is interrupted at the corresponding second anti-breaking grid line, and each second thin grid is interrupted at the corresponding first anti-breaking grid line; At least part of the first thin grids are provided with first welding parts between two adjacent anti-breaking grid line groups, at least part of the second thin grids are provided with second welding parts between two adjacent anti-breaking grid line groups, the second welding parts are spaced from the first welding parts in the first direction, the first welding parts and the second welding parts are used for welding with welding strips, the first thin grids are not provided with the first welding parts between the first anti-breaking grid line and the second anti-breaking grid line, and the second thin grids are not provided with the second welding parts between the first anti-breaking grid line and the second anti-breaking grid line. In some embodiments, in the anti-break grid line group, a distance between the first anti-break grid line and the second anti-break grid line is 0.1mm-12mm. In some embodiments, in the anti-break grid line group, a distance between the first anti-break grid line and the second anti-break grid line is 0.1mm-5mm. In some embodiments, the spacing between adjacent first and second welds is 0.5mm-20mm. In some embodiments, the spacing between adjacent first and second welds is 2mm-15mm. In some embodiments, the first thin grid has at least one first welded portion between two adjacent anti-break grid line groups, and the second thin grid has at least one second welded portion between two adjacent anti-break grid line groups. In some embodiments, the first thin grid has only one first welded portion between two adjacent anti-break grid line groups, and the second thin grid has only one second welded portion between two adjacent anti-break grid line groups; The distance between two adjacent anti-breaking grid line groups is L1, and the distance between the first welding part and the second welding part between two adjacent anti-breaking grid line groups is L2, wherein L1/L2 is more than or equal to 1.2 and less than or equal to 10. In some embodiments, the arrangement manner of the first anti-break gate line and the second anti-break gate line in two adjacent anti-break gate line groups is the same, wherein the first anti-break gate line of one anti-break gate line group is adjacent to the second anti-break gate line group of the other anti-break gate line group. In some embodiments, the first thin grid has only one first welded portion between two adjacent anti-break grid line groups, and the second thin grid has only one second welded portion between two adjacent anti-break grid line groups; The first fine grid comprises first grid line segments positioned between adjacent anti-breaking grid line groups, the first grid line segments comprise first welding parts, first parts positioned between the first welding parts and the first anti-breaking grid lines in one anti-breaking grid line gr