Pattern structure for preventing grid line at edge of battery piece from falling off and battery piece

Abstract

The utility model discloses a pattern structure for preventing grid lines at the edge of a battery piece from falling off and the battery piece, which belong to the technical field of photovoltaic bonding pad groups, and comprise a main printing pattern and an auxiliary printing pattern, the main printing pattern comprises a plurality of bonding pad groups arranged in parallel, the bonding pad groups comprise a plurality of main grid lines arranged in parallel, and the auxiliary printing pattern comprises a plurality of auxiliary grid lines arranged in parallel. The main grid lines comprise end welding disc points located at the ends of the main grid lines and internal welding disc points distributed between the two end welding disc points at intervals, connecting lines are arranged between the end welding disc points and the internal welding disc points or between the two internal welding disc points, and the width of the connecting lines on the main grid lines is gradually increased from the middle to the two sides; the end bonding pad point is provided with a harpoon line, a first frame auxiliary grid line is connected between the adjacent harpoon lines deviating from the other bonding pad group, and the main grid line is perpendicular to the first frame auxiliary grid line. A first frame auxiliary grid line and a second frame auxiliary grid line are arranged on the edge of the corresponding main grid, and the poor falling of the edge grid lines is improved by using the high reliability of the main grid slurry.

Description

Technical Field

[0001] The utility model belongs to the technical field of photovoltaic modules, and particularly relates to a graphic structure and a battery chip for preventing the edge grid lines of battery chips from falling off. Background Art

[0002] Crystalline silicon solar cells are semiconductor devices that convert solar energy into electrical energy. The solar cell chips collect solar energy, collect the photocurrent converted from solar energy through the electrode grid lines, and deliver the photocurrent to a load for use. Therefore, there is an optimal design problem of the battery grid line structure corresponding to the efficient battery structure design. The way of grid line design is closely related to the power output of photovoltaic cells. In the prior art, the industry trend of the production process of crystalline silicon solar cell chips is to print the main grid lines that provide welding reliability and the secondary grid lines that provide ohmic contact separately, and the main grid paste and the secondary grid paste are developed differently. The greater development requirement of the main grid paste is to provide welding reliability to ensure that the battery chips meet the reliability requirements for a certain number of years after being made into modules. The greater development requirement of the secondary grid paste is to provide ohmic contact to ensure the conversion efficiency of the battery chips.

[0003] In the actual production of crystalline silicon solar cells, laser-assisted sintering is introduced to improve the yield of battery chips. Laser-assisted sintering essentially separates the two key steps of passivation layer erosion and contact formation during the high-temperature sintering process by utilizing the highly concentrated energy and controllable characteristics of the laser, so as to achieve further precise control of the sintering process. With the development and introduction of the laser-assisted sintering process, the sintering process temperature for metallization is reduced by 20 - 50 °C, resulting in insufficient metallization between the secondary grid lines on the battery chips and the silicon wafer substrate during the sintering process stage. One frame secondary grid line at each edge of the battery chip is prone to break away from the silicon wafer substrate, forming a grid line falling-off phenomenon, which leads to poor appearance degradation of the battery chips and affects the yield of battery chip products.

[0004] Some patents on the grid line structure of battery chips are disclosed in the prior art. Among them, the utility model patent with the patent publication number CN215771169U discloses a main grid screen pattern of a crystalline silicon solar cell with an integrated anti-breaking grid line design, which has main grid lines and anti-breaking grid lines parallel to the main grid lines. The opening width of the main grid lines is 100 μm - 700 μm, and the opening width of the anti-breaking grid lines is 15 μm - 60 μm. Although it has the effect of reducing the area of the laser SE heavily doped region and carrier recombination of the integrated anti-breaking grid line, there is still a problem that the secondary grid lines at the edge of the battery chip fall off after subsequent cutting of the laser-assisted sintering process, resulting in poor appearance degradation of the battery chips and affecting the yield of battery chip products.

[0005] In view of this, the inventor of the present case conducted in-depth research on this demand, and thus this case was born. Summary of the Utility Model

[0006] To overcome the problems existing in the prior art, namely, the shedding of the secondary grid lines at the edges of the battery chips and the shedding of the secondary grid lines at the edges of the battery chips after subsequent cutting in the laser-assisted sintering process, which lead to poor appearance of the battery chips and degradation of the yield of the battery chip products, the present utility model provides a graphic structure and a battery chip for preventing the shedding of the grid lines at the edges of the battery chips.

[0007] The present utility model provides a graphic structure for preventing the shedding of the grid lines at the edges of the battery chips, including a main printing graphic and a secondary printing graphic. The main printing graphic includes a plurality of pad groups arranged in parallel. Each pad group includes a plurality of main grid lines arranged in parallel. The plurality of main grid lines include end pad points located at the ends of the main grid lines and internal pad points distributed at intervals between the two end pad points. A connecting line is provided between the end pad points and the internal pad points or between two internal pad points. The width of the connecting line on the main grid line gradually increases from the middle to both sides.

[0008] Harpoon lines are provided at the end pad points. A first frame secondary grid line is connected between the adjacent harpoon lines facing away from the other pad group. The main grid line is perpendicular to the first frame secondary grid line.

[0009] By arranging a first frame secondary grid line between adjacent harpoon lines at the end pad points and designing one frame secondary grid line at the outermost edge perpendicular to the main grid to be printed on the main grid, the high reliability of the main grid paste is utilized to improve the defect of the shedding of the edge grid lines, and finally the yield of the battery is improved.

[0010] Further, the secondary printing graphic includes a plurality of secondary grid lines arranged in parallel and reserved hollow parts corresponding to the plurality of end pad points for arranging the main grid. The secondary grid lines are perpendicular to the connecting lines.

[0011] In the middle of the secondary printing graphic, a second frame secondary grid line is provided between the adjacent harpoon lines in the same pad group. A cutting schematic line of the pad group is provided between the two relatively parallel second frame secondary grid lines.

[0012] Further, four overprint holes are symmetrically opened on the main printing graphic. Overprint alignment points corresponding to the overprint holes are provided on the secondary printing graphic. The overprint alignment points are accommodated in the overprint holes to make the main printing graphic and the secondary printing graphic match. The main printing graphic uses a non-burn-through type front silver paste, and the secondary printing graphic uses a burn-through type front silver paste.

[0013] Further, a first connecting grid is provided on the connecting line close to the end pad point. The first connecting grid is used to connect the main grid line and the secondary grid line. The extending direction of the first connecting grid is perpendicular to the direction of the connecting line.

[0014] Further, a connecting portion is provided on the sub-grid line. The connecting portion includes a second connecting grid, which is arranged corresponding to the first connecting grid and is used to connect the first connecting grid and the sub-grid line, or the sub-grid line and the main grid line.

[0015] Further, the first connecting grid and / or the second connecting grid is trapezoidally arranged. The height of the trapezoidal connecting grid is parallel to the sub-grid line. The upper base of the trapezoidal connecting grid is close to the sub-grid line, and the lower base is close to the main grid line. The length of the lower base is greater than that of the upper base. The length of the base of the trapezoidal connecting grid close to the sub-grid line is greater than or equal to the width of the sub-grid line.

[0016] The connecting portion further includes an intermediate portion located between the two second connecting grids. The intermediate portion is located between the lower bases of the two second connecting grids, corresponds to the connecting line, and is used to connect with the connecting line.

[0017] Further, border lines are provided around the main printing pattern and the sub-printing pattern. The border lines are used to connect the main grid line or the sub-grid line. The width of the second connecting grid line gradually decreases from the direction close to the border line to the direction of the sub-grid line.

[0018] Further, anti-breaking thin grid lines are provided between the sub-grid lines, and the anti-breaking thin grid lines are perpendicular to the sub-grid lines.

[0019] Further, the size of the end solder pads is larger than that of the internal solder pads.

[0020] The present utility model also provides a battery cell for preventing the edge grid lines of the battery cell from falling off, including the graphic structure as described above.

[0021] The beneficial effects produced by adopting the technical solution of the present utility model are as follows:

[0022] (1) By arranging the first border sub-grid lines between adjacent harpoon lines at the end solder pads, and designing one border sub-grid line on each edge perpendicular to the main grid to be printed on the main grid, the problem of edge grid line shedding is improved by using the high reliability of the main grid paste, and finally the yield of the battery is increased.

[0023] (2) By arranging the second border sub-grid lines corresponding to the harpoon lines in the middle of the main printing pattern on the sub-printing pattern, the border sub-grid lines at the ends of the middle harpoon lines are continuously printed on the overall sub-grid line drawing, and a solder pad group cutting schematic line is arranged between the opposite second border sub-grid lines to facilitate the cutting of subsequent processes. At the same time, the arranged second border sub-grid lines avoid the shedding of edge grid lines. Description of the Drawings

[0024] To more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present utility model, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0025] Figure 1 It is a schematic diagram of the main printing pattern of the graphic structure for preventing the edge grid lines of the battery chip from falling off according to the present utility model;

[0026] Figure 2 It is a schematic diagram of the secondary printing pattern of the graphic structure for preventing the edge grid lines of the battery chip from falling off according to the present utility model

[0027] In the figure, 1, main printing pattern; 2, secondary printing pattern; 3, main grid line; 4, end welding point; 5, internal welding point; 6, connecting line; 7, harpoon line; 8, first frame secondary grid line; 9, secondary grid line; 10, reserved hollow area; 11, second frame secondary grid line; 12, cutting schematic line; 13, overprinting hole; 14, overprinting alignment point; 15, frame line; 16, anti-breaking fine grid line. Specific embodiments

[0028] To make the purpose, technical solutions and advantages of the embodiments of the present utility model clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present utility model in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all of the embodiments. Therefore, the detailed description of the embodiments of the present utility model provided in the following drawings is not intended to limit the scope of the claimed present utility model, but only represents the selected embodiments of the present utility model. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0029] In this embodiment, a first frame secondary grid line is arranged between adjacent harpoon lines at the end welding point, and one frame secondary grid line at each edge perpendicular to the main grid is designed to be printed on the main grid. The high reliability of the main grid paste is used to improve the defect of edge grid line shedding, and finally the yield of the battery is improved. The specific implementation is as follows:

[0030] Such as Figure 1-2As shown in the figure, a graphic structure for preventing the edge grid lines of battery chips from falling off includes a main printing graphic 1 and a secondary printing graphic 2. The main printing graphic 1 includes several groups of pads arranged in parallel. Each group of pads includes several main grid lines 3 arranged in parallel. The several main grid lines 3 include end pad points 4 at the ends of the main grid lines 3 and internal pad points 5 distributed at intervals between the two end pad points 4. A connecting line 6 is provided between the end pad points 4 and the internal pad points 5 or between two internal pad points 5. The width of the connecting line 6 on the main grid line 3 gradually increases from the middle to both sides.

[0031] Harpoon lines 7 are provided at the end pad points 4. A first frame secondary grid line 8 is connected between adjacent harpoon lines 7 that face away from another group of pads. The main grid line 3 is perpendicular to the first frame secondary grid line 8.

[0032] Here, by providing the first frame secondary grid line 8 between adjacent harpoon lines 7 at the end pad points 4 and designing one frame secondary grid line 9 at each edge perpendicular to the main grid to be printed on the main grid, the high reliability of the main grid paste is used to improve the problem of poor edge grid line falling off, and finally the yield of the battery is improved.

[0033] As a preferred embodiment, the secondary printing graphic 2 includes several secondary grid lines 9 arranged in parallel and reserved hollow areas 10 corresponding to several end pad points 4 for setting the main grid. The secondary grid lines 9 are perpendicular to the connecting line 6.

[0034] In the middle of the secondary printing graphic 2, a second frame secondary grid line 11 is provided between adjacent harpoon lines 7 within the same group of pads. A pad group cutting indication line 12 is provided between two relatively parallel second frame secondary grid lines 11.

[0035] Here, the second frame secondary grid line 11 is provided on the secondary printing graphic 2 corresponding to the harpoon lines 7 in the middle of the main printing graphic 1. The frame secondary grid line 9 at the end of the middle harpoon line 7 continues to be printed on the overall drawing of the secondary grid lines 9. And a pad group cutting indication line 12 is provided between the opposite second frame secondary grid lines 11, which is convenient for cutting in subsequent processes. At the same time, the provided second frame secondary grid line 11 ensures that the edge grid lines do not fall off.

[0036] As a preferred embodiment, four overprint holes 13 are symmetrically provided on the main printing graphic 1. Overprint alignment points 14 corresponding to the overprint holes 13 are provided on the secondary printing graphic 2. The overprint alignment points 14 are accommodated in the overprint holes 13 to make the main printing graphic 1 and the secondary printing graphic 2 match. The main printing graphic 1 uses a non-burn-through type front silver paste, and the secondary printing graphic 2 uses a burn-through type front silver paste.

[0037] As a preferred embodiment, a first connection grid is provided on the connecting line 6 close to the end pad point 4. The first connection grid is used to connect the main grid line 3 and the secondary grid line 9. The extending direction of the first connection grid is perpendicular to the direction of the connecting line 6.

[0038] As a preferred embodiment, a connecting portion is provided on the secondary gate line 9. The connecting portion includes a second connecting gate, which is arranged corresponding to the first connecting gate, and the second connecting gate is used to connect the first connecting gate and the secondary gate line 9, or the secondary gate line 9 and the main gate line 3.

[0039] As a preferred embodiment, the first connecting gate and / or the second connecting gate are trapezoidally arranged. The height of the trapezoidal connecting gate is parallel to the secondary gate line 9. The upper base of the trapezoidal connecting gate is close to the secondary gate line 9, and the lower base of the trapezoidal connecting gate is close to the main gate line 3. The length of the lower base is greater than that of the upper base. The length of the base of the trapezoidal connecting gate close to the secondary gate line 9 is greater than or equal to the width of the secondary gate line 9.

[0040] The connecting portion further includes an intermediate portion located between the two second connecting gates. The intermediate portion is located between the lower bases of the two second connecting gates, corresponding to the connecting line 6, and the intermediate portion is used to connect with the connecting line 6.

[0041] As a preferred embodiment, a border line 15 is provided around the main printing pattern 1 and the secondary printing pattern 2. The border line 15 is used to connect the main gate line 3 or the secondary gate line 9. The width of the second connecting gate line gradually decreases from the direction close to the border line 15 to the direction of the secondary gate line 9.

[0042] As a preferred embodiment, anti-breaking thin gate lines 16 are provided between the secondary gate lines 9, and the anti-breaking thin gate lines 16 are arranged perpendicular to the secondary gate lines 9.

[0043] As a preferred embodiment, the size of the end soldering pad 4 is larger than that of the internal soldering pad 5.

[0044] This embodiment also provides a solar cell for preventing the gate lines at the edge of the solar cell from falling off, including the above graphic structure.

[0045] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A graphic structure for preventing the edge grid lines of battery chips from falling off, characterized in that, It includes a main printed pattern (1) and a secondary printed pattern (2). The main printed pattern (1) includes a plurality of pad groups arranged in parallel. Each pad group includes a plurality of main grid lines (3) arranged in parallel. The plurality of main grid lines (3) include end pad points (4) located at the ends of the main grid lines (3) and internal pad points (5) spaced between the two end pad points (4). A connection line (6) is provided between the end pad points (4) and the internal pad points (5) or between two internal pad points (5). The width of the connection line (6) on the main grid line (3) gradually increases from the middle to both sides; Harpoon lines (7) are provided at the end pad points (4). A first border secondary grid line (8) is connected between adjacent harpoon lines (7) that face away from the other pad group. The main grid line (3) is perpendicular to the first border secondary grid line (8).

2. The graphic structure for preventing the edge grid lines of a battery chip from falling off according to claim 1, characterized in that, The secondary printed pattern (2) includes a plurality of secondary grid lines (9) arranged in parallel and reserved hollow areas (10) for the main grid corresponding to a plurality of the end pad points (4). The secondary grid lines (9) are perpendicular to the connection line (6); In the middle of the secondary printed pattern (2), a second border secondary grid line (11) is provided between adjacent harpoon lines (7) within the same pad group. A pad group cutting indication line (12) is provided between two relatively parallel second border secondary grid lines (11).

3. A graphic structure for preventing the edge grid lines of a battery cell from falling off according to claim 1, characterized in that, Four overprint holes (13) are symmetrically provided on the main printed pattern (1). Overprint alignment points (14) corresponding to the overprint holes (13) are provided on the secondary printed pattern (2). The overprint alignment points (14) are received in the overprint holes (13) to match the main printed pattern (1) and the secondary printed pattern (2). The main printed pattern (1) uses a non-burn-through type positive silver paste, and the secondary printed pattern (2) uses a burn-through type positive silver paste.

4. A graphic structure for preventing the edge grid lines of a battery cell from falling off according to claim 1, characterized in that, A first connection grid is provided on the connection line (6) close to the end pad point (4). The first connection grid is used to connect the main grid line (3) and the secondary grid line (9). The extending direction of the first connection grid is perpendicular to the direction of the connection line (6).

5. A graphic structure for preventing the edge grid lines of battery chips from falling off according to claim 4, characterized in that, A connection portion is provided on the secondary grid line (9). The connection portion includes a second connection grid. The second connection grid is provided corresponding to the first connection grid. The second connection grid is used to connect the first connection grid and the secondary grid line (9), or the secondary grid line (9) and the main grid line (3).

6. A graphic structure for preventing the edge grid lines of a battery cell from falling off according to claim 5, characterized in that, The first connection grid and / or the second connection grid is trapezoidally arranged. The height of the trapezoidal connection grid is parallel to the secondary grid line (9). The upper base of the trapezoidal connection grid is close to the secondary grid line (9). The lower base of the trapezoidal connection grid is close to the main grid line (3). The length of the lower base is greater than the length of the upper base. The length of the base of the trapezoidal connection grid close to the secondary grid line (9) is greater than or equal to the width of the secondary grid line (9); The connection portion further includes an intermediate portion located between the two second connection grids. The intermediate portion is located between the lower bases of the two second connection grids. The intermediate portion corresponds to the connection line (6). The intermediate portion is used to connect to the connection line (6).

7. A graphic structure for preventing the edge grid lines of a battery cell from falling off according to claim 5, characterized in that, A border line (15) is provided around the main printing pattern (1) and the secondary printing pattern (2). The border line (15) is used to connect the main grid line (3) or the secondary grid line (9). The width of the second connecting grid gradually decreases from the direction close to the border line (15) to the direction of the secondary grid line (9).

8. A graphic structure for preventing the edge grid lines of battery chips from falling off according to claim 1, characterized in that, An anti-break fine grid line (16) is provided between the secondary grid lines (9). The anti-break fine grid line (16) is perpendicular to the secondary grid line (9).

9. A graphic structure for preventing the edge grid lines of a battery cell from falling off according to claim 1, characterized in that, The size of the end soldering pad (4) is larger than the size of the internal soldering pad (5).

10. A solar cell for preventing the edge grid lines of the solar cell from falling off, characterized in that, It includes the graphic structure described in any one of claims 1-9.

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