Solar cell, photovoltaic module and photovoltaic system

Abstract

The utility model discloses a solar cell sheet, a photovoltaic assembly and a photovoltaic system, the solar cell sheet comprises a cell sheet body, a plurality of main grids which are arranged on the cell sheet body along the transverse direction at intervals and a plurality of fine grids which are arranged on the cell sheet body along the longitudinal direction at intervals, the main grids extend along the longitudinal direction, every two main grids form a group, and the fine grids are arranged on the cell sheet body along the longitudinal direction at intervals. A main grid gap is formed in each group of main grids, the fine grids extend along the transverse direction, the fine grids and the main grids are arranged in an intersecting manner, welding strips which are arranged along the longitudinal direction are arranged in the main grid gaps, and the welding strips are connected with the fine grids positioned in the main grid gaps. According to the utility model, the thin grids in the gaps of the main grids are directly connected with the welding strip, current can be effectively collected under the condition that part of the thin grids in the gaps of the main grids are broken, and the influence of the broken grid condition on the electrical performance of the solar cell is reduced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to photovoltaic technical field, especially relate to a solar cell piece, photovoltaic module and photovoltaic system. BACKGROUND

[0002] The grid line on the solar cell piece is usually printed to the surface of the solar cell piece by screen printing process with conductive paste (such as silver paste), to form the grid line, and the main function of these grid lines is to collect and transmit current. The grid line on the surface of the solar cell piece includes a main grid and a fine grid electrically connected with the main grid. The connection between the solder strip and the solar cell piece is realized by welding the solder strip with the main grid, and then the current transmission between two solar cell pieces can be realized through the solder strip. In order to reduce the influence of broken grid on the performance of solar cell piece in the process of series welding, the overlapping position of the fine grid and the main grid is designed with a gradually thickening structure on the fine grid, which is used to reduce the risk of broken grid.

[0003] However, in order to reduce the shading area of the metal electrode in the design of improving the conversion efficiency of the solar cell piece, the width of the fine grid is gradually narrowed, and the current gradually thickening structure cannot effectively ensure the stability of welding. After the solder strip is welded with the main grid, the solder shrinks in the cooling process, and the alloy point position formed by the main grid and the fine grid is easy to break due to shrinkage, which forms the problem of broken grid and affects the electrical performance of the solar cell piece. SUMMARY

[0004] The utility model discloses a solar cell piece, photovoltaic module and photovoltaic system to solve the above technical problems, which can cancel the existing fine grid gradually thickening structure at the intersection of the fine grid and the main grid, connect the fine grid in the main grid gap of each group of main grid with the solder strip, and effectively collect current even if there is broken grid in the fine grid in the main grid gap, thereby reducing the influence of broken grid on the electrical performance of the solar cell piece. In order to achieve the above purpose, the technical scheme of the utility model is as follows:

[0005] A solar cell piece includes a cell piece body, a plurality of main grids arranged along the transverse direction and a plurality of fine grids arranged along the longitudinal direction, the main grids extend along the longitudinal direction, each two main grids form a group, and a main grid gap is formed in each group of main grids, the fine grids extend along the transverse direction, the fine grids intersect with the main grids, a solder strip is arranged in the main grid gap along the longitudinal direction, and the solder strip is connected with the fine grid in the main grid gap.

[0006] Optionally, each group of main grids is provided with a plurality of electrode points spaced apart along the longitudinal direction. Each electrode point includes an electrode body and an extension line disposed on both sides of the electrode body. The electrode body is disposed on the battery cell body and is connected to two main grids in each group. The extension line extends to cover the intersection of the fine grid and the main grid.

[0007] Optionally, the electrode body is connected to the solder strip, and the width of the extension line is greater than the width of the fine grid.

[0008] Optionally, the fine grid extends through the gap between the main grids and overlaps with the main grids; or the fine grids are segmented, with the end of each segment of the fine grid abutting against the adjacent main grid.

[0009] Optionally, each of the two ends of the main grids in each group of main grids is connected to a harpoon grid line, and the two harpoon grid lines corresponding to each group of main grids form a group and a harpoon opening is formed between each group of harpoon grid lines. The harpoon opening is connected to the main grid through a gap, and the fine grid is intersected with the harpoon grid lines.

[0010] Optionally, the ends of two adjacent harpoon grid lines in two adjacent sets of harpoon grid lines are connected by a first edge grid line; in two opposing sets of harpoon grid lines located on both sides of the solar cell and at the edge, the outer harpoon grid line is connected by a second edge grid line located at the edge of the solar cell, the second edge grid line passing through the ends of several fine grids.

[0011] Optionally, each group of main grids is equidistantly spaced along the transverse direction, and a plurality of fine grids are equidistantly spaced along the longitudinal direction. Electrode points are equidistantly spaced along the longitudinal direction on each group of main grids, and the distance between the main grid gaps is 500-1500μm.

[0012] Optionally, the battery cell body is provided with several columns of auxiliary grids spaced apart along the horizontal direction, and at least one column of auxiliary grids is provided between each group of adjacent main grids. Each column of auxiliary grids includes several auxiliary grids spaced apart along the vertical direction, and each auxiliary grid is connected to the adjacent fine grids.

[0013] Optionally, the length of the electrode body is 500-2000 μm, and the width of the electrode body is 200-1500 μm.

[0014] A photovoltaic module includes the aforementioned solar cell and solder ribbon, wherein fine grids within the main grid gaps on the solar cell are connected to the solder ribbon.

[0015] A photovoltaic system, comprising the aforementioned photovoltaic module.

[0016] Compared with the prior art, the beneficial effects of the solar cell and photovoltaic module of this utility model are mainly reflected in:

[0017] When the partial fine grid in the main grid gap has a broken grid, the solder strip can still collect current independently by directly contacting the fine grid in the main grid gap. In the case of canceling the fine grid gradual thickening structure at the intersection of the main grid and the fine grid, the influence of solder strip string broken grid on the electrical performance of the solar cell is reduced.

[0018] In addition, by changing the fine grid gradual thickening structure, the fine grid with uniform width is printed on the solar cell, which effectively reduces the silver paste usage of the fine grid, and further reduces the manufacturing cost. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 A structure schematic diagram of a solar cell according to an embodiment of the present application is provided.

[0020] Figure 2 A local enlarged schematic diagram of a solar cell according to an embodiment of the present application is provided.

[0021] Figure 3 A main grid arrangement schematic diagram according to an embodiment of the present application is provided.

[0022] Figure 4 A fine grid arrangement schematic diagram according to an embodiment of the present application is provided.

[0023] REFERENCE NUMERALS:

[0024] Main grid 1, main grid gap 11;

[0025] Fine grid 2;

[0026] Electrode point 3, electrode body 31, extension line 32;

[0027] Fork grid line 4, fork mouth 41, first edge grid line 42, second edge grid line 43;

[0028] Auxiliary grid 5. DETAILED DESCRIPTION

[0029] In order to make the technical solutions and advantages in the embodiments of the present application clearer, the exemplary embodiments of the present application are further described in detail below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0030] Embodiment one

[0031] The present embodiment provides a solar cell, which comprises a cell body, a plurality of main grids 1 arranged along the transverse direction and a plurality of fine grids 2 arranged along the longitudinal direction. Among them, the main grid 1 is arranged on the cell body, and the fine grid 2 is arranged on the cell body. Figure 1The transverse direction and the longitudinal direction shown in the figure determine the orientation of the battery piece body.

[0032] As Figures 1-4 shown, the solar cell provided by the embodiment is provided with two main grids 1 in each group, the main grids 1 are arranged in the longitudinal direction, the main grid gap 11 is formed in each group of main grids 1, the fine grid 2 is arranged in the transverse direction, the fine grid 2 is arranged intersecting the main grid 1, the solder strip (not shown in the figure) arranged in the longitudinal direction is arranged in the main grid gap 11, and the solder strip is connected with the fine grid 2 located in the main grid gap 11. Specifically, the solder strip is welded and fixed with the fine grid 2 located in the main grid gap 11, the solder strip can be in a state of being non-parallel to the main grid 1, which reduces the operation difficulty of welding the solder strip on the fine grid 2 in the main grid gap 11. Even if the solder strip is inclined relative to the main grid 1, the solder strip is still kept in the main grid gap 11, which does not affect the current collection of the solder strip from the fine grid 2.

[0033] The fine grid 2 penetrates the main grid gap 11 and overlaps the main grid 1. It can be understood that the fine grid 2 is first formed on the battery piece body, and then the main grid 1 is formed on the battery piece body again. The fine grid 2 and the main grid 1 are in an overlapping state, which ensures that the main grid 1 is accurately located at the position set by the fine grid 2, improves the mechanical stability of the connection between the main grid 1 and the fine grid 2, and the existence of the main grid 1 can provide additional support for the fine grid 2, reducing the risk of fracture caused by external stress.

[0034] Or the fine grid 2 is arranged in sections, and the end of each section of the fine grid 2 abuts against the adjacent main grid 1. It can be understood that the fine grid 2 does not have to penetrate and overlap the main grid 1, and the two ends of the fine grid 2 located in the main grid gap 11 can abut against two main grids 1, thereby reducing the amount of silver paste used by the fine grid 2 and achieving the effect of saving costs. The arrangement mode of the above fine grid 2 can be adaptively selected according to different process requirements.

[0035] A plurality of electrode points 3 are arranged on each group of main grids 1 in the longitudinal direction, the electrode point 3 includes an electrode body 31 and an extension line 32 arranged on both sides of the electrode body 31; the electrode body 31 is arranged on the battery piece body, and the electrode body 31 is connected with two main grids 1 in each group. Specifically, the electrode body 31 can be connected to two main grids 1 in a group in the transverse direction, the extension line 32 extends and covers the intersection of the fine grid 2 and the main grid 1, and the width of the extension line 32 is greater than the width of the fine grid 2. The extension line 32 can enhance the connection performance of the intersection of the fine grid 2 and the main grid 1, and avoid the problem of grid breakage caused by the influence of heat on the electrode point 3.

[0036] The electrode body 31 is connected with the fine grid 2 located in the main grid gap 11, and the electrode body 31 is connected with the solder strip, which is welded and fixed on the surface of the electrode body 31. In order to further strengthen the connection stability of the solder strip and the fine grid 2 located in the main grid gap 11, the solder strip is stably connected on the battery piece body through the electrode body 31. In the case that the solder strip is not connected with the main grid 1, even if part of the fine grid 2 in the main grid gap 11 has a grid breakage problem, the solder strip can still remain in a fixed state, thereby ensuring the lead current.

[0037] In this embodiment, the main grid 1, the fine grid 2 and the electrode point 3 are all formed by printing conductive paste through a printing screen plate.

[0038] In this embodiment, when part of the fine grid 2 in the main grid gap 11 has a grid breakage, the solder strip can still independently collect current by directly connecting with the fine grid 2 in the main grid gap 11. In the case that the fine grid 2 gradually thickening structure at the intersection of the traditional main grid 1 and the fine grid 2 is cancelled, the influence of the solder strip string solder grid breakage on the electrical performance of the solar cell piece is reduced. Due to the change of the fine grid 2 gradually thickening structure, the fine grid 2 with uniform width is printed on the solar cell piece, which effectively reduces the silver paste usage of the fine grid 2, and further reduces the manufacturing cost.

[0039] Embodiment two

[0040] This embodiment is based on the above-mentioned embodiments, and optimizes the solar cell piece, especially provides a specific implementation manner of the main grid and the fine grid:

[0041] As shown in Figure 1 , Figure 2 Each of the two main grids 1 in the above-mentioned each group of main grids 1 is respectively connected with a fish fork grid line 4, and the two fish fork grid lines 4 corresponding to each group of main grids 1 form a group and form a fish fork opening 41 between each group of fish fork grid lines 4. The fish fork opening 41 is provided through the main grid gap 11 of each group of main grids 1. The width of the fish fork opening 41 gradually expands from the main grid gap 11 to the outside of the solar cell piece. The design of the fish fork grid line 4 reduces the shading of the incident sunlight as much as possible, ensures that more light can reach the battery piece body and be converted into electrical energy, and the fish fork grid line 4 provides a low-resistance path, so that electrons can be quickly collected.

[0042] The fish fork opening 41 is intersected with the fine grid 2, specifically the fine grid 2 extending in the transverse direction penetrates the fish fork opening 41 and is overlapped with the fish fork grid line 4. The fine grid 2 and the fish fork grid line 4 are in an overlapping state, which improves the mechanical stability of the connection between the fish fork grid line 4 and the fine grid 2, and reduces the risk of breakage caused by external stress.

[0043] Or the fine grid 2 is arranged in sections, the end of each section of the fine grid 2 abuts the adjacent fish fork grid line 4, it can be understood that the fine grid 2 does not have to be arranged through the fish fork grid line 4, the two ends of the fine grid 2 located in the fish fork mouth 41 can abut two fish fork grid lines 4, thereby reducing the amount of silver paste used by the fine grid 2, achieving the effect of saving cost.

[0044] The ends of the adjacent two fish fork grid lines 4 in the two adjacent groups of fish fork grid lines 4 are connected by the first edge grid line 42. In the two groups of fish fork grid lines 4 located on both sides of the solar cell and at the edges, the fish fork grid line 4 located on the outside is connected by the second edge grid line 43 provided at the edge of the solar cell, and the second edge grid line 43 connects the ends of several fine grids 2. The first edge grid line 42 and the second edge grid line 43 can provide better mechanical support for the cell body, so that the current is more evenly distributed on the entire cell body surface, improving the overall efficiency of the solar cell.

[0045] The width of the main grid 1 in the embodiment is 20-100 μm, that is, the cross-sectional dimension of the main grid 1 along the transverse direction. The distance of the main grid gap 11 is 500-1500 μm, that is, the distance between each group of main grids 1 along the transverse direction, which can be 500 μm, 700 μm, 900 μm, 1000 μm, 1200 μm or 1500 μm, etc. The distance of the main grid gap 11 is adapted to the width of the solder strip, so that the solder strip can be completely located in the main grid gap 11, allowing the solder strip to have a deflection error in the main grid gap 11.

[0046] Each group of main grids 1 is arranged equidistantly along the transverse direction, and a plurality of fine grids 2 are arranged equidistantly along the longitudinal direction. The width of the fine grid 2 in the embodiment is 10-40 μm, that is, the cross-sectional dimension of the fine grid 2 along the longitudinal direction, which can be 10 μm, 20 μm, 30 μm or 40 μm, etc. The main grid 1 and the fine grid 2 are uniformly distributed on the cell body to achieve uniform distribution of current and improve the efficiency and reliability of the solar cell.

[0047] The electrode point 3 is arranged equidistantly along the longitudinal direction on each group of main grids 1, the length of the electrode body 31 of the electrode point 3 is 500-2000 μm, that is, the distance of the electrode body 31 along the transverse direction, which can be 500 μm, 800 μm, 1000 μm, 1400 μm, 1600 μm, 1800 μm or 2000 μm, etc.; the width of the electrode body 31 is 200-1500 μm, that is, the distance of the electrode body 31 along the longitudinal direction, which can be 200 μm, 400 μm, 600 μm, 800 μm, 1000 μm, 1300 μm or 1500 μm, etc. The electrode point 3 is uniformly distributed on the cell body, effectively leading out the current through the solder strip, and can also provide stable support for the solder strip.

[0048] The solar cell is provided with a plurality of auxiliary grids 5 arranged in intervals in the lateral direction, and at least one auxiliary grid 5 is arranged between two adjacent main grids 1. Each auxiliary grid 5 includes a plurality of auxiliary grids 5 arranged in intervals in the longitudinal direction, and each auxiliary grid 5 is connected to adjacent fine grids 2. The auxiliary grid 5 is arranged on the solar cell to increase the density of the electrode network, so that the electrons can reach the nearest electrode point 3 in a shorter distance, thereby reducing the resistance loss and effectively improving the efficiency of the solar power conversion. In addition, the introduction of the auxiliary grid 5 can reduce the width of the fine grid 2 without sacrificing the current collection efficiency, thereby reducing the shading area of the fine grid 2 to the incident sunlight and increasing the proportion of the effective illumination area, further improving the photoelectric conversion efficiency. Finally, the auxiliary grid 5 can also play a role in strengthening the structure, helping to disperse the stress applied to the solar cell body and reducing the risk of cracks or other forms of physical damage.

[0049] Embodiment three

[0050] The embodiment provides a photovoltaic module, which includes the solar cell and the solder strip in the above embodiments, and the fine grid in the main grid gap of the solar cell is connected with the solder strip. Details are described in the foregoing embodiments, and will not be described here.

[0051] Embodiment four

[0052] The embodiment provides a photovoltaic system, which includes the photovoltaic module in the above embodiments.

[0053] In the description of the present application, it should be understood that the terms "longitudinal", "lateral", "length", "width", "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0054] In addition, the terms "first", "second" are only used for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0055] In this application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixed", and the like, should be construed in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection or can communicate with each other; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0056] Although the preferred embodiments of the present application have been described, those skilled in the art can make further changes and modifications to these embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including all the preferred embodiments and all the changes and modifications falling within the scope of the present application.

[0057] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.

Claims

1. A solar cell, characterized by: The solar cell piece comprises a cell piece body, a plurality of main grids arranged on the cell piece body in a transverse direction and a plurality of thin grids arranged in a longitudinal direction, the main grids extend in the longitudinal direction, two main grids form a group, a main grid gap is formed between the two main grids in each group, the thin grids extend in the transverse direction, the thin grids are arranged transversely to the main grids, a solder strip is arranged in the main grid gap in the longitudinal direction, and the solder strip is connected to the thin grid in the main grid gap.

2. The solar cell of claim 1, wherein: A plurality of electrode points are arranged on each group of main grids in the longitudinal direction, the electrode points comprise an electrode body and an extension line arranged on both sides of the electrode body, the electrode body is arranged on the cell piece body, the electrode body is connected to the two main grids in each group, and the extension line extends over the intersection of the thin grid and the main grid.

3. The solar cell of claim 2, wherein: The electrode body is connected to the solder strip, and the width of the extension line is greater than the width of the thin grid.

4. The solar cell of claim 1, wherein: The thin grid penetrates the main grid gap and overlaps the main grid. Or the thin grid is arranged in segments, and the end of each segment of the thin grid abuts against the adjacent main grid.

5. The solar cell of claim 1, wherein: The end of each of the two main grids in each group of main grids is connected to a fork grid line, two fork grid lines corresponding to each group of main grids form a group, and a fork opening is formed between each group of fork grid lines, the fork opening is arranged through the main grid gap, and the thin grid is arranged transversely to the fork grid line.

6. The solar cell of claim 5, wherein: The ends of two adjacent fork grid lines in two adjacent groups of fork grid lines are connected by a first edge grid line, and in the two groups of fork grid lines located on the two sides of the solar cell piece and at the edges, the outer fork grid line is connected by a second edge grid line arranged at the edge of the solar cell piece, and the second edge grid line connects the ends of a plurality of thin grids.

7. The solar cell of claim 1, wherein: Each group of main grids is arranged at equal intervals in the transverse direction, a plurality of thin grids are arranged at equal intervals in the longitudinal direction, electrode points are arranged at equal intervals in the longitudinal direction on each group of main grids, and the distance between the main grid gaps is 500-1500 μm. A plurality of auxiliary grids are arranged at equal intervals in the transverse direction on the cell piece body, at least one auxiliary grid is arranged between each group of adjacent main grids, each auxiliary grid comprises a plurality of auxiliary grids arranged at equal intervals in the longitudinal direction, and each auxiliary grid connects adjacent thin grids.

8. The solar cell of claim 2, wherein: The length of the electrode body is 500-2000 μm, and the width of the electrode body is 200-1500 μm.

9. A photovoltaic module characterized by: The solar cell piece comprises a cell piece body, a plurality of main grids arranged on the cell piece body in a transverse direction and a plurality of thin grids arranged in a longitudinal direction, the main grids extend in the longitudinal direction, two main grids form a group, a main grid gap is formed between the two main grids in each group, the thin grids extend in the transverse direction, the thin grids are arranged transversely to the main grids, a solder strip is arranged in the main grid gap in the longitudinal direction, and the solder strip is connected to the thin grid in the main grid gap.

10. A photovoltaic system characterized by: The solar cell piece comprises a cell piece body, a plurality of main grids arranged on the cell piece body in a transverse direction and a plurality of thin grids arranged in a longitudinal direction, the main grids extend in the longitudinal direction, two main grids form a group, a main grid gap is formed between the two main grids in each group, the thin grids extend in the transverse direction, the thin grids are arranged transversely to the main grids, a solder strip is arranged in the main grid gap in the longitudinal direction, and the solder strip is connected to the thin grid in the main grid gap.

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