WO2016065953A1

WO2016065953A1 - Solar cell module and manufacturing method thereof

Info

Publication number: WO2016065953A1
Application number: PCT/CN2015/084116
Authority: WO
Inventors: Zhiqiang Zhao; Zhanfeng Jiang; Long He
Original assignee: Byd Company Limited
Priority date: 2014-10-31
Filing date: 2015-07-15
Publication date: 2016-05-06

Abstract

A solar cell module (100) and a manufacturing method thereof are disclosed. The solar cell module (100) includes an upper cover plate (10), a front adhesive layer (20), a transparent film frame (60), a cell array (30), a back adhesive layer (40) and a back plate (50) superposed in sequence, the cell array (30) including a plurality of cells (31) and conductive wires (32) connected with secondary grid lines (312) on the cells (30), two adjacent cells (30) being connected by the conductive wires (32), the transparent film frame (60) constituted by a longitudinal adhesive tape (61) and a transverse adhesive tape (62) intersected with each other, and the conductive wire (32) formed with a metal wire and bonded with the longitudinal adhesive tape (61).

Description

SOLAR CELL MODULE AND MANUFACTURING METHOD THEREOF

FIELD

The present disclosure relates to a field of solar cells, and more particularly, to a solar cell module and a manufacturing method thereof.

BACKGROUND

A solar cell module is one of the most important components of a solar power generation device. Sunlight irradiates onto a cell from its front surface and is converted to electricity within the cell. Primary grid lines and secondary grid lines are disposed on the front surface. And then a welding strip covering and welded on the primary grid lines outputs the current. The welding strip, the primary grid lines and the secondary grid lines cover part of the front surface of the cell, which blocks out part of the sunlight, and the part of sunlight irradiating onto the primary grid lines and the secondary grid lines cannot be converted into electric energy. Thus, the welding strip, the primary grid lines and the secondary grid lines need to be designed as fine as possible in order for the solar cell module to receive more sunlight. However, the welding strip, the primary grid lines and the secondary grid lines serve to conduct current, and in terms of resistivity, the finer the primary grid lines and the secondary grid lines are, the smaller the conductive cross section area thereof is, which causes greater loss of electricity due to increased resistivity. Therefore, the welding strip, the primary grid lines and the secondary grid lines shall be designed to get a balance between light blocking and electric conduction, and to take the cost into consideration.

SUMMARY

The present disclosure is based on discoveries and understanding of the applicant to the following facts and problems.

In prior art, the primary grid lines and the secondary grid lines of the solar cells are made of expensive silver paste, which results in complicated manufacturing process of the primary grid lines and the secondary grid lines and high cost. When the cells are connected to form a module, the primary grid lines on the front surface of a cell are welded with back electrodes of another adjacent cell by a solder strip. Consequently, the welding of the primary grid lines is complicated, and the manufacturing cost of the cells is high.

In prior art, two primary grid lines are usually disposed on the front surface of the cell, and formed by applying silver paste to the front surface of the cell. The primary grid lines have a great width (for example, up to over 2mm) , which consumes a large amount of silver, and makes the cost high.

In prior art, a solar cell with three primary grid lines is provided, but this kind of solar cell still consumes a large amount of silver, and has a high cost. Moreover, three primary grid lines increase the shading area, which lowers the photoelectric conversion efficiency.

In addition, the number of the primary grid lines is limited by the solder strip. The larger the number of the primary grid lines is, the finer a single primary grid line is, and hence the solder strip needs to be narrower. Therefore, it is more difficult to weld the primary grid lines with the solder strip and to produce the narrower solder strip, and thus the cost of the welding rises up.

Consequently, from the perspective of lowering the cost and reducing the shading area, the prior art replaces the silver primary grid lines printed on the cell with metal wires, for example, copper wires. The copper wires are welded with the secondary grid lines to output the current. Since the silver primary grid lines are no longer used, the cost can be reduced considerably. The copper wire has a smaller diameter to reduce the shading area, so the number of the copper wires can be raised up to 10. This kind of cell may be called a cell without primary grid lines, in which the metal wire replaces the silver primary grid lines and solder strips in the traditional solar cells.

In prior art, there is a technical solution that the electrical connection of the metal wire and the cells is formed by laminating a transparent film pasted with metal wires and the cells, i.e. multiple parallel metal wires being fixed on the transparent film by adhesion, then being stuck on the cell, and finally being laminated to contact with the secondary grid lines on the cell. However, since the metal wires are pasted and fixed on the transparent film by a bonding layer whose melting point is relatively low, the bonding layer may melt or be softened in the laminating process, and thus the metal wires will drift to some extent. In addition, the transparent film may affect light absorption.

Thus, in the field of solar cells, the structure of the solar cell is not complicated, but each component is crucial. The production of the primary grid lines takes various aspects into consideration, such as shading area, electric conductivity, equipment, process, cost, etc., and hence becomes a difficult and hot issue in the solar cell technology. In the market, a solar cell with two primary grid lines is replaced with a solar cell with three primary grid lines in 2007 through huge efforts of those skilled in the art. A few factories came up with a solar cell with four primary grid lines around 2014. The concept of multiple primary grid lines is put forward in the recent years, but still there is no fairly mature product.

The present disclosure seeks to solve at least one of the problems existing in the related art to at least some extent.

The present disclosure provides a solar cell without primary grid lines, which needs neither primary grid line nor sold strip disposed on the cells, and thus lowers the cost. The solar cell without primary grid lines can be commercialized for mass production, easy to manufacture with simple equipment, especially in low cost, and moreover have high photoelectric conversion efficiency.

According to a first aspect of embodiments of the present disclosure, a solar cell module includes an upper cover plate, a front adhesive layer, a transparent film frame, a cell array, a back adhesive layer and a back plate superposed in sequence, the cell array including a plurality of cells and conductive wires connected with secondary grid lines on the cells, two adjacent cells being connected by the conductive wires, the transparent film frame constituted by a longitudinal adhesive tape and a transverse adhesive tape intersected with each other, and the conductive wire formed with a metal wire and bonded with the longitudinal adhesive tape.

In the solar cell module according to embodiments of the present disclosure, the conductive wires constituted by the metal wire are bound with the longitudinal adhesive tape of the transparent film frame, and then connected with the secondary grid lines of the cell, so as to guarantee the stability of connecting the conductive wires and the secondary grid lines and to reduce the shading area of the transparent film frame, to guarantee the photoelectric conversion efficiency of the solar cell module.

According to a second aspect of embodiments of the present disclosure, a method for manufacturing a solar cell module includes: binding a metal wire with a longitudinal adhesive tape on a transparent film frame constituted by the longitudinal adhesive tape and a transverse adhesive tape； superposing an upper cover plate, a front adhesive layer, a cell array, a back adhesive layer and a back plate in sequence, in which the front surface of the cell faces the front adhesive layer, a back surface thereof facing the back adhesive layer, and laminating them to obtain the solar cell module, in which the metal wire is connected with the secondary grid lines of the cells in the cell array.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a plan view of a solar cell array according to an embodiment of the present disclosure；

Fig. 2 is a transverse sectional view of a solar cell array according to an embodiment of the present disclosure；

Fig. 3 is a longitudinal sectional view of a solar cell array according to embodiments of the present disclosure；

Fig. 4 is a schematic diagram of a metal wire for forming a conductive wire according to embodiments of the present disclosure；

Fig. 5 is a plan view of a solar cell array according to another embodiment of the present disclosure；

Fig. 6 is a plan view of a solar cell array according to another embodiment of the present disclosure；

Fig. 7 is a schematic diagram of a metal wire extending reciprocally according to embodiments of the present disclosure；

Fig. 8 is a schematic diagram of two cells of a solar cell array according to embodiments of the present disclosure；

Fig. 9 is a sectional view of a solar cell array formed by connecting, by a metal wire, the two cells according to Fig. 8；

Fig. 10 is a schematic diagram of a solar cell module according to embodiments of the present disclosure；

Fig. 11 is a sectional view of part of the solar cell module according to Fig. 10；

Fig. 12 is a schematic diagram of a solar cell array according to another embodiment of the present disclosure；

Fig. 13 is a schematic diagram of a transparent film frame according to an embodiment of the present disclosure.

Reference numerals:

100 cell module

10 upper cover plate

20 front adhesive layer

30 cell array

31 cell

31A first cell

31B second cell

311 cell substrate

312 secondary grid line

312A front secondary grid line

312B back secondary grid line

313 back electric field

314 back electrode

32 conductive wire

32A front conductive wire

32B back conductive wire

321 metal wire body

322 connection material layer

33 short grid line

40 back adhesive layer

50 back plate

60 transparent film frame

61 longitudinal adhesive tape

62 transverse adhesive tape

DETAILED DESCRIPTION

Embodiments of the present disclosure will be described in detail and examples of the embodiments will be illustrated in the drawings, where same or similar reference numerals are used to indicate same or similar members or members with same or similar functions. The embodiments described herein with reference to the drawings are explanatory, which are used to illustrate the present disclosure, but shall not be construed to limit the present disclosure.

Part of technical terms in the present disclosure will be elaborated herein for clarity and convenience of description.

According to embodiments of the present disclosure, a cell 31 includes a cell substrate 311, secondary grid lines 312 disposed on a front surface (the surface on which light is incident) of the cell substrate 311, a back electric field 313 disposed on a back surface of the cell substrate 311, and back electrodes 314 disposed on the back electric field 313. Thus, the secondary grid lines 312 can be called the secondary grid lines 312 of the cell 31, the back electric field 313 called the back electric field 313 of the cell 31, and the back electrodes 314 called the back electrodes 314 of the cell 31.

A cell substrate 311 can be an intermediate product obtained by subjecting, for example, a silicon chip to processes of felting, diffusing, edge etching and silicon nitride layer depositing. However, it shall be understood that the cell substrate 311 in the present disclosure is not limited to be formed by the silicon chip, but includes any other suitable solar cell substrate 311.

In other words, the cell 31 comprises a silicon chip, some processing layers on a surface of the silicon chip, secondary grid lines on a shiny surface (namely a front surface) , and a back electric field 313 and back electrodes 314 on a shady surface (namely a back surface) , or includes other equivalent solar cells of other types without any front electrode.

A cell unit includes a cell 31 and conductive wires 32 constituted by a metal wire S.

A solar cell array 30 includes a plurality of cells 31 and conductive wires 32 which connect adjacent cells 31 and are constituted by the metal wire S. In other words, the solar cell array 30 is formed of a plurality of cells 31 connected by the conductive wires 32.

In the solar cell array 30, the metal wire S constitutes the conductive wires 32 of the cell unit, and extends between surfaces of the adjacent cells 31, which shall be understood in a broad sense that the metal wire S may extend between front surfaces of the adjacent cells 31, or may extend between a front surface of a first cell 31 and a back surface of a second cell 31 adjacent to the first cell 31. When the metal wire S extends between the front surface of the first cell 31 and the back surface of the second cell 31 adjacent to the first cell 31, the conductive wires 32 may include front conductive wires 32A extending on the front surface of the cell 31 and electrically connected with the secondary grid lines 312 of the cell 31, and back conductive wires 32B extending on the back surface of the cell 31 and electrically connected with the back electrodes 314 of the cell 31. Part of the metal wire S between the adjacent cells 31 can be called connection conductive wires.

In the present disclosure, the cell substrate 311, the cell 31, the cell unit, the cell array 30 and the solar cell module are only for the convenience of description, and shall not be construed to limit the present disclosure.

All the ranges disclosed in the present disclosure include endpoints, and can be individual or combined. It shall be understood that the endpoints and any value of the ranges are not limited to an accurate range or value, but also include values proximate the ranges or values.

In the present disclosure, the orientation terms such as “upper” and “lower” usually refer to the orientation “upper” or “lower” as shown in the drawings under discussion, unless specified otherwise； “front surface” refers to a surface of the solar cell module facing the light in practical application (for example, when the module is in operation) , i.e. a shiny surface on which light is incident, while “back surface” refers to a surface of the solar cell module back to the light in practical application.

Moreover, in the present disclosure, the metal wire S refers to a metal wire for extending reciprocally on the cells 31 to form the conductive wires 32； and the conductive wires 32 may be a metal wire body 321, or may include a metal wire body 321 and a connection material layer 322 coating the surface of the metal wire body 321, i.e. the metal wire S can be the metal wire body 321, or can consist of the metal wire body 321 and the connection material layer 322 coating the surface of the metal wire body 321. In the embodiments of the present disclosure, unless specified otherwise, the metal wire represents the metal wire S which extends reciprocally on the cells to form the conductive wires 32.

In the following, a solar cell module 100 according to the embodiments of the present disclosure will be described with respect to the drawings.

As shown in Fig. 1 to Fig. 13, the solar cell module 100 according to the embodiments of the present disclosure includes an upper cover plate 10, a front adhesive layer 20, a cell 31, a back adhesive layer 40 and a back plate 50.

Specifically, the cell array 30 includes a plurality of cells 31 and conductive wires 32 connected with secondary grid lines 312 on the cells 31, and two adjacent cells 31 are connected by the conductive wires 32； the transparent film frame 60 constituted by a longitudinal adhesive tape 61 and a transverse adhesive tape 62 intersected with each other, and the conductive wire 32 formed with a metal wire S and bonded with the longitudinal adhesive tape 61.

In other words, the solar cell module 100 according to the embodiments of the present disclosure includes an upper cover plate 10, a front adhesive layer 20, a transparent film frame 60, a cell array 30, a back adhesive layer 40 and a back plate 50 superposed sequentially from up to down. The cell 31 consists of a cell substrate 311 and the secondary grid lines 312 disposed on the cell substrate 311. The cell array 30 includes a plurality of cells 31 and the conductive wires 32 connected with secondary grid lines 312 on the cells 31, and two adjacent cells 31 are connected by the conductive wires 32. The transparent film frame 60 is constituted by a longitudinal adhesive tape 61 and a transverse adhesive tape 62 intersected with each other, and the conductive wires 32 are formed with a metal wire S and bonded with the longitudinal adhesive tape 61.

The transparent film frame 60 is constituted by the longitudinal adhesive tape 61 and the transverse adhesive tape 62 intersected with each other, instead of having a whole film structure. The transparent film frame 60 is provided with the longitudinal adhesive tape 61 and the transverse adhesive tape 62 only at a position where they are in need, and remains spare space in other portions, which reduces the light shading of the transparent film and facilitates light absorption of the solar cell, and hence improves the photoelectric conversion efficiency of the solar cell module. The metal wire S for constituting the conductive wires 32 is bounded with the longitudinal adhesive tape 61 of the transparent film frame 60, in which the binding can be implemented by melting. In other words, the metal wire S for constituting the conductive wires 32 is arranged on the transparent film frame 60, and heated, such that the portion where the transparent film frame 60 and the metal wire S are in contact will melt to connect the metal wire S with the transparent film frame 60, so as to fix the metal wire S on the transparent film frame 60. Hence, the metal wire S will not drift in the laminating process, which guarantees the stability of connecting the conductive wire 32 and the secondary grid line 312.

Thus, in the solar cell module 100 according to the embodiments of the present disclosure, the conductive wires 32 constituted by the metal wire S are bound with the longitudinal adhesive tape 61 of the transparent film frame 60, and then connected with the secondary grid lines 312 of the cell 31, so as to prevent the metal wire from drifting, to guarantee the stability of connecting the conductive wires 32 and the secondary grid lines 312, to reduce the shading area of the transparent film frame 60, and to guarantee the photoelectric conversion efficiency of the solar cell module 100.

The front adhesive layer 20 and the back adhesive layer 40 are adhesive layers commonly used in the art. Preferably, the front adhesive layer 20 and the back adhesive layer 40 are polyethylene-octene elastomer (POE) and/or ethylene-vinyl acetate copolymer (EVA) . In the present disclosure, polyethylene-octene elastomer (POE) and/or ethylene-vinyl acetate copolymer (EVA) are conventional products in the art, or can be obtained in a method known to those skilled in the art.

In the embodiments of the present disclosure, the upper cover plate 10 and the back plate 50 can be selected and determined by conventional technical means in the art. Preferably, the upper cover plate 10 and the back plate 50 can be transparent plates respectively, for example, glass plates.

Other components of the solar cell module 100 according to the present disclosure are known in the art, which will be not described in detail herein.

According to an embodiment of the present disclosure, the transverse adhesive tape 62 and the longitudinal adhesive tape 61 are welded or integrated by the adhesive or heating at a position where they are intersected.

That’s to say, the transparent film frame 60 can have a film structure integrally formed, or can be formed by binding or welding the transverse adhesive tape 62 and the longitudinal adhesive tape 61 at the position where they are intersected. Thus, the transparent film frame 60 of this structure is easy to manufacture in low cost.

It shall be noted that in the present disclosure, the metal wire S refers to a metal wire for extending reciprocally on the cells 31 to form the conductive wires 32； and the conductive wires 32 may include a metal wire body 321 and a connection material layer 322 coating the metal wire body 321, i.e. the metal wire S can consist of the metal wire body 321 and the connection material layer 322 coating the metal wire body 321. In the embodiment of the present disclosure, unless specified otherwise, the metal wire refers to the metal wire S for extending reciprocally on the cells 31 to form the conductive wires 32.

In some embodiments, preferably, the metal wire body 321 is a copper wire, i.e. the metal wire S can be a copper wire, too. In other words, the metal wire does not include the coating layer, but the present disclosure does not limited thereto. For example, the metal wire body 321 can be an aluminum wire. In the present disclosure, preferably, the metal wire body 321 has a circular cross section, such that more sunlight can reach the cell substrate to further improve the photoelectric conversion efficiency.

The metal wire body 321 is coated with the connection material layer 322, such that it is convenient to electrically connect the metal with the secondary grid lines and/or the back electrodes, and to avoid drifting of the metal wire in the connection process so as to guarantee the photoelectric conversion efficiency. Of course, the electrical connection of the metal with the cell substrate can be conducted during or before the laminating process of the solar cell module, and preference is given to the latter.

In some other specific embodiments of the present disclosure, the metal wire body 321 is coated with a welding layer, and a ratio of a thickness of the welding layer and a diameter of the metal wire is (0.02-0.5) : 1.

That’s to say, in the present disclosure, the connection material layer 322 is a welding layer, and a ratio of a thickness of the welding layer and a diameter of the metal wire falls into the range of (0.02-0.5) : 1.

Specifically, the welding layer contains Sn, and at least one of Bi, In, Ag, Sb, Pb and Zn. Alternatively, the welding layer contains Sn, Bi, and at least one of In, Ag, Sb, Pb and Zn.

As shown in Fig. 13, in the present disclosure, the transparent film frame 60 is constituted by the longitudinal adhesive tape 61 and the transverse adhesive tape 62 intersected with each other. Multiple longitudinal adhesive tapes 61 can be arranged in parallel； multiple transverse adhesive tapes 62 can be also arranged in parallel； and the longitudinal adhesive tape 61 is perpendicular to the transverse adhesive tape 62.

In some specific embodiments of the present disclosure, the metal wire body 321 has a diameter of 0.05 to 0.5mm. Preferably, the metal wire body 321 has a diameter of 0.15 to 0.25mm. Preferably, the transverse adhesive tape 62 has a width of 0.1 to 5mm. Further, the transverse adhesive tape 62 has a width of 0.5 to 2mm.

In some examples, there are 1 to 10 transverse adhesive tapes 62. Preferably, there are 2 to 4 transverse adhesive tapes 62. In some examples, the transverse adhesive tape 62 has a thickness of 0.05 to 0.5mm. Preferably, the transverse adhesive tape has a thickness of 0.1 to 0.2mm.

Correspondingly, the longitudinal adhesive tape 61 has a width of 0.5 to 5mm. Preferably, the longitudinal adhesive tape 61 has a width of 1 to 3mm. There are 2 to 10 longitudinal adhesive tapes 61, preferably 2 to 4 longitudinal adhesive tapes 61. In some specific embodiments of the present disclosure, the longitudinal adhesive tape 61 has a thickness of 0.05 to 0.5mm. Preferably, the longitudinal adhesive tape 61 has a thickness of 0.1 to 0.2mm.

Thus, the metal wire body 321 of this structure can coordinate with the longitudinal adhesive tapes 61 and the secondary grid lines 312 on the cell 31； the transverse adhesive tapes 62 can fix the longitudinal adhesive tapes 61 better to guarantee the stability of the whole structure of the transparent film frame 60.

In some specific embodiments of the present disclosure, the solar cell array 30 includes multiple cells 31, adjacent cells 31 connected by the plurality of conductive wires 32. The conductive wires 32 are constituted by the metal wire S that is electrically connected with the cell 31, and extends reciprocally between the surfaces of the adjacent cells 31.

Specifically, there are multiple cells 31 to form the cell array 30. The adjacent cells 31 are connected with the metal wire S. The metal wire S is electrically connected with the cells 31 and extends reciprocally between a surface of a first cell 31 and a surface of a second cell 31 adjacent to the first cell 31.

Preferably, there are multiple cells 31 to form the cell array 30. The adjacent cells 31 are connected with the metal wire S. The metal wire S is electrically connected with the cells 31 and extends reciprocally between a front surface of the first cell 31 and a back surface of the second cell 31 adjacent to the first cell 31, to connect the adjacent cells in series.

In the embodiment, the transparent film frame 60 is disposed between the front adhesive layer 20 and the upper surface of the first cell 31 (i.e. the shiny surface of the first cell 31) , and the conductive wires 32 are disposed between the transparent film frame 60 and the upper surface of the first cell 31. The conductive wires 32 are constituted by the metal wire S, bound with the transparent film frame 60 and exposed therefrom, and are electrically with the secondary grid line 312 on the front surface of the first cell 31. In the embodiment, the conductive wires 32 are in contact with the back electrodes of the back surface of the second cell 31 to form electric connection.

In some other embodiments of the present disclosure, the transparent film frame 60 is disposed between the front adhesive layer 20 and the upper surface of the first cell 31 (i.e. the shiny surface of the first cell 31) , and the conductive wires 32 are disposed between the transparent film frame 60 and the upper surface of the first cell 31. The conductive wires 32 are constituted by the metal wire S, bound with the transparent film frame 60 and exposed therefrom, and are electrically with the secondary grid line 312 on the front surface of the first cell 31. Further, the transparent film frame 60 is also disposed between the back adhesive layer 40 and the lower surface of the second cell 31 (i.e. the shady surface of the second cell 31) , and the conductive wires 32 are disposed on the surface of the transparent film frame 60 opposite the second cell 31, and are inserted into the transparent film frame 60 and exposed therefrom. The conductive wire 32 is formed of a metal wire and connected with the secondary grid line 312. The conductive wires 32 are constituted by the metal wire S, bound with the transparent film frame 60 and exposed therefrom, and are in contact with the back electrodes 314 of the back surface of the second cell 31 to form electric connection.

Specifically, in the solar cell module 100 of the present disclosure, the front conductive wires 32A are disposed on the front surface of the cell 31, and the back conductive wires 32B are disposed on the back surface of another adjacent cell 31. The front conductive wires 32A disposed on the front surface of the cell 31 are connected with the secondary grid lines 312 of the cell 31； and the back conductive wires 32B disposed on the back surface of the second cell 31 are connected with the back electrodes 314 of the cell 31.

In the present disclosure, the conductive wires 32 (including the front conductive wires 32A and the back conductive wires 32B) can be inserted in the transparent film frame 60 by melting. The melting method includes: arranging the conductive wires 32 in the surface of the transparent film frame 60； heating the conductive wires 32 (e.g. electrical heating) , such that the contact portion of the transparent film frame 60 and the conductive wires 32 is softened or melted, so as to melt and fix the conductive wires 32 and the transparent film frame 60 together.

Preferably, a first end of the conductive wire is arranged on the lower surface of the first transparent film frame 60, and a second end of the conductive wire is arranged on the upper surface of the second transparent film frame 60, and then the conductive wire is heated (e.g. electrical heating) , such that the contact portion of the transparent film frame 60 and the conductive wires 32 is softened or melted, so as to melt and fix the conductive wires 32 and the transparent film frame 60 together. The first transparent film frame 60 whose lower surface is melted with the conductive wires faces a front surface of a first cell 31, such that the conductive wires 32 are connected with the secondary grid lines 312 on the front surface of the first cell； the second transparent film frame 60 whose upper surface is melted with the conductive wires faces a back surface of a second cell 31, such that the conductive wires 32 are connected with the back electrodes 314 on the back surface of the second cell； part of the conductive wires 32 welded with the secondary grid lines on the front surface of the first cell are called front conductive wires 32A, and part of the conductive wires 32 welded with the back electrodes on the back surface of the second cell are called back conductive wires 32B.

The cell unit is formed by the cell 31 and the conductive wires 32 constituted by the metal wire S which extends on the surface of the cell 31. In other words, the solar cell array 30 according to the embodiments of the present disclosure are formed with a plurality of cell units； the conductive wires 32 of the plurality of cells are formed by the metal wire S which extends reciprocally between the surfaces of the cells 31.

It shall be understood that the term “extending reciprocally” in the application can be called “winding” which refers to that the metal wire S extends between the surfaces of the cells 31 along a reciprocal route.

In the present disclosure, it shall be understood in a broad sense that “the metal wire S extends reciprocally between surfaces of the cells 31. For example, the metal wire S may extend reciprocally between a front surface of a first cell 31 and a back surface of a second cell 31 adjacent to the first cell 31； the metal wire S may extend from a surface of the first cell 31 through surfaces of a predetermined number of middle cells 31 to a surface of the last cell 31, and then extends back from the surface of the last cell 31 through the surfaces of a predetermined number of middle cells 31 to the surface of the first cell 31, extending reciprocally like this.

In addition, when the cells 31 are connected in parallel by the metal wire S, the metal wire S can extend on front surfaces of the cells 31, such that the metal wire S constitutes front conductive wires 32A. Alternatively, a first metal wire S extends reciprocally between the front surfaces of the cells 31, and a second metal wire S extends reciprocally between the back surfaces of the cells 31, such that the first metal wire S constitutes front conductive wires 32A, and the second metal wire S constitutes back conductive wires 32B.

When the cells 31 are connected in series by the metal wire S, the metal wire S can extend reciprocally between a front surface of a first cell 31 and a back surface of a second cell 31 adjacent to the first cell 31, such that part of the metal wire S which extends on the front surface of the first cell 31 constitutes front conductive wires 32A, and part thereof which extends on the back surface of the second cell 31 constitutes back conductive wires 32B. In the present disclosure, unless specified otherwise, the conductive wires 32 can be understood as the front conductive wires 32A, the back conductive wires 32B, or the combination thereof.

The term “extending reciprocally” can be understood as that the metal wire S extends reciprocally once to form to two conductive wires 32 which are formed by winding a metal wire S. For example, two adjacent conductive wires form a U-shape structure or a V-shape structure, yet the present disclosure is not limited to the above.

In the solar cell array 30 according to the embodiments of the present disclosure, the conductive wires 32 of the plurality of cells 31 are constituted by the metal wire S which extends reciprocally； and the adjacent cells 31 are connected by the conductive wires 32. Hence, the conductive wires 32 of the cells are not necessarily made of expensive silver paste, and can be manufactured in a simple manner without using a solder strip to connect the cells. It is easy and convenient to connect the metal wire S with the secondary grid lines and the back electrodes, so that the cost of the cells is reduced considerably.

Moreover, since the conductive wires 32 are constituted by the metal wire S which extends reciprocally, the width of the conductive wires 32 (i.e. the width of projection of the metal wire on the cell) may be decreased, thereby decreasing the shading area of the conductive wires 32. Further, the number of the conductive wires 32 can be adjusted easily, and thus the resistance of the conductive wires 32 is reduced, compared with the primary grid lines made of the silver paste, and the photoelectric conversion efficiency is improved. Since the metal wire S extends reciprocally to form the conductive wires, when the cell array 30 is used to manufacture the solar cell module 100, the metal wire S will not tend to shift, i.e. the metal wire is not easy to “drift” , which will not affect but further improve the photoelectric conversion efficiency.

Therefore, the solar cell array 30 according to the embodiments of the present disclosure has low cost and high photoelectric conversion efficiency.

Moreover, it shall be noted that in the present disclosure, the conductive wires 32 can be constituted by the metal wire S which is coated with the conductive adhesive and extends reciprocally between the surfaces of the adjacent cells, or can be arranged by multiple metal wires in parallel to and spaced apart from each other. It is understandable for those skilled in the art that in the technical solution a plurality of individual metal wires are spaced apart from each other to form the primary grid lines of the traditional structure, which will not be described in detail.

In the following, the solar cell array 30 according to specific embodiments of the present disclosure will be described with reference to the drawings.

The solar cell array 30 according to a specific embodiment of the present disclosure is illustrated with reference to Fig. 1 to Fig. 3.

In the embodiment shown in Fig. 1 to Fig. 3, two cells 31 in the solar cell array 30 are shown. In other words, it shows two cells 31 connected with each other via the conductive wires 32 constituted by the metal wire S.

It can be understood that the cell 31 comprises a cell substrate 311, secondary grid lines 312 (i.e. front secondary grid lines 312A) disposed on a front surface of the cell substrate 311, a back electric field 313 disposed on a back surface of the cell substrate 311, and back electrodes 314 disposed on the back electric field 313. In the present disclosure, it shall be understood that the back electrodes 314 may be back electrodes of a traditional cell, for example, printed by the silver paste, or may be back secondary grid lines 312B similar to the secondary grid lines on the front surface of the cell substrate, or may be multiple discrete welding portions, unless specified otherwise. The secondary grid lines refer to the secondary grid lines 312 on the front surface of the cell substrate 311, unless specified otherwise.

As shown in Fig. 1 to Fig. 3, the solar cell array in the embodiment includes two

cells

31A, 31B (called a first cell 31A and a second cell 31B respectively for convenience of description) . The metal wire S extends reciprocally between the front surface of the first cell 31A (a shiny surface, i.e. an upper surface in Fig. 2) and the back surface of the second cell 31B, such that the metal wire S constitutes front conductive wires of the first cell 31A and back conductive wires of the second cell 31B. The metal wire S is electrically connected with the secondary grid lines of the first cell 31A (for example, being welded or bound by a conductive adhesive) , and electrically connected with the back electrodes of the second cell 31B.

In some embodiments, the metal wire extends reciprocally between the first cell 31A and the second cell 31B for 10 to 60 times to form 20 to 120 conductive wires. Preferably, as shown in Fig. 1, the metal wire extends reciprocally for 12 times to form 24 conductive wires 32, and there is only one metal wire. In other words, a single metal wire extends reciprocally for 12 times to form 24 conductive wires, and the distance of the adjacent conductive wires can range from 2.5mm to 15mm. In this embodiment, the number of the conductive wires is increased, compared with the traditional cell, such that the distance between the secondary grid lines and the conductive wires which the current runs through is decreased, so as to reduce the resistance and improve the photoelectric conversion efficiency. In the embodiment shown in Fig. 1, the adjacent conductive wires form a U-shape structure, for convenience of winding the metal wire. Alternatively, the present disclosure is not limited to the above. For example, the adjacent conductive wires can form a V-shape structure.

In some embodiments, preferably, before the metal wire contact the cells, the metal wire extends under strain, i.e. straightening the metal wire. After the metal wire is connected with the secondary grid lines and the back electrodes of the cell, the strain of the metal wire can be released, so as to further avoid the drifting of the conductive wires when the solar cell module is manufactured, and to guarantee the photoelectric conversion efficiency.

Fig. 5 is a schematic diagram of a solar cell array according to another embodiment of the present disclosure. As shown in Fig. 5, the metal wire extends reciprocally between the front surface of the first cell 31A and the front surface of the second cell 31B, such that the metal wire constitutes front conductive wires of the first cell 31A and front conductive wires of the second cell 31B. In such a way, the first cell 31A and the second cell 31B are connected in parallel. Of course, it can be understood that preferably the back electrodes of the first cell 31A and the back electrodes of the second cell 31B can be connected via back conductive wires constituted by another metal wire which extends reciprocally. Alternatively, the back electrodes of the first cell 31A and the back electrodes of the second cell 31B can be connected in a traditional manner.

The solar cell array 30 according to another embodiment of the present disclosure is illustrated with reference to Fig. 6.

The solar cell array 30 according to the embodiment of the present disclosure comprises n×m cells 31. In other words, a plurality of cells 31 are arranged in an n×m matrix form, n representing a column, and m representing a row. More specifically, in the embodiment, 36 cells 31 are arranges into six columns and six rows, i.e. n＝m＝6. It can be understood that the present disclosure is not limited thereto. For example, the column number and the row number can be different. For convenience of description, in Fig. 6, in a direction from left to right, the cells 31 in one row are called a first cell 31, a second cell 31, a third cell 31, a fourth cell 31, a fifth cell 31, and a sixth cell 31 sequentially； in a direction from up to down, the columns of the cells 31 are called a first column of cells 31, a second column of cells 31, a third column of cells 31, a fourth column of cells 31, a fifth column of cells 31, and a sixth column of cells 31 sequentially.

In a row of the cells 31, the metal wire extends reciprocally between a surface of a first cell 31 and a surface of a second cell 31 adjacent to the first cell 31； in two adjacent rows of cells 31, the metal wire extends reciprocally between a surface of a cell 31 in a a^th row and a surface of a cell 31 in a (a+1) ^th row, and m-1≥a≥1.

As shown in Fig. 6, in a specific example, in a row of the cells 31, the metal wire extends reciprocally between a front surface of a first cell 31 and a back surface of a second cell 31 adjacent to the first cell 31, so as to connect the cells 31 in one row in series. In two adjacent rows of cells 31, the metal wire extends reciprocally between a front surface of a cell 31 at an end of the a^th row and a back surface of a cell 31 at an end of the (a+1) ^th row, to connect the two adjacent rows of cells 31 in series.

More preferably, in the two adjacent rows of cells 31, the metal wire extends reciprocally between the surface of the cell 31 at an end of the a^th row and the surface of the cell 31 at an end of the (a+1) ^th row, the end of the a^th row and the end of the (a+1) ^th row located at the same side of the matrix form, as shown in Fig. 6, located at the right side thereof.

More specifically, in the embodiment as shown in Fig. 6, in the first row, a first metal wire extends reciprocally between a front surface of a first cell 31 and a back surface of a second cell 31； a second metal wire extends reciprocally between a front surface of the second cell 31 and a back surface of a third cell 31； a third metal wire extends reciprocally between a front surface of the third cell 31 and a back surface of a fourth cell 31； a fourth metal wire extends reciprocally between a front surface of the fourth cell 31 and a back surface of a fifth cell 31； a fifth metal wire extends reciprocally between a front surface of the fifth cell 31 and a back surface of a sixth cell 31. In such a way, the adjacent cell bodies 31 in the first row are connected in series by corresponding metal wires.

A sixth metal wire extends reciprocally between a front surface of the sixth cell 31 in the first row and a back surface of a sixth cell 31 in the second row, such that the first row and the second row are connected in series. A seventh metal wire extends reciprocally between a front surface of the sixth cell 31 in the second row and a back surface of a fifth cell 31 in the second row； a eighth metal wire extends reciprocally between a front surface of the fifth cell 31 in the second row and a back surface of a fourth cell 31 in the second row, until a eleventh metal wire extends reciprocally between a front surface of a second cell 31 in the second row and a back surface of a first cell 31 in the second row, and then a twelfth metal wire extends reciprocally between a front surface of the first cell 31 in the second row and a back surface of a first cell 31 in the third row, such that the second row and the third row are connected in series. Sequentially, the third row and the fourth row are connected in series, the fourth row and the fifth row connected in series, the fifth row and the sixth row connected in series, such that the cell array 30 is manufactured. In this embodiment, a bus bar is disposed at the left side of the first cell 31 in the first row and the left side of the first cell 31 in the sixth row respectively； a first bus bar is connected with the conductive wires extending from the left side of the first cell 31 in the first row, and a second bus bar is connected with the conductive wires extending from the left side of the first cell 31 in the sixth row.

As said above, the cell bodies in the embodiments of the present disclosure are connected in series by the conductive wires–the first row, the second row, the third row, the fourth row, the fifth row and the sixth row are connected in series by the conductive wires. As shown in the figures, alternatively, the second and third row, and the fourth and fifth rows can be connected in parallel with a diode respectively to avoid light spot effect. The diode can be connected in a manner commonly known to those skilled in the art, for example, by a bus bar.

However, the present disclosure is not limited to the above. For example, the first and second rows can be connected in series, the third and fourth rows connected in series, the fifth and sixth rows connected in series, and meanwhile the second and third rows are connected in parallel, the fourth and fifth connected in parallel. In such a case, a bus bar can be disposed at the left or right side of corresponding rows respectively.

Alternatively, the cells 31 in the same row can be connected in parallel. For example, a metal wire extends reciprocally from a front surface of a first cell 31 in a first row through the front surfaces of the second to the sixth cells 31.

Fig. 12 shows a schematic diagram of a solar cell array according to another embodiment of the present disclosure. As shown in Fig. 12, short grid lines 33 and secondary grid lines 312 are disposed at the front surface of the cell 31； the secondary grid lines 312 include middle secondary grid lines intersected with the conductive wires and edge secondary grid lines non-intersected with the conductive wires； the short lines 33 are connected with the edge secondary grid lines, and connected with the conductive wires or at least one middle secondary grid line. Preferably, the short grid lines 33 are perpendicular to the secondary grid lines 312.

Consequently, the short grid lines 33 are disposed at the edges of the shiny surface of the cell 31, so as to avoid partial current loss because the conductive wires 32 cannot reach the secondary grid lines 312 at the edges of the cell 31 in the winding process, and to further improve the photoelectric conversion efficiency of the solar cell module 100.

In some specific embodiments of the present disclosure, the binding force between the metal wire and the cells 31 ranges from 0.1N to 0.8N. That’s to say, the binding force between the conductive wires 32 and the cells 31 ranges from 0.1N to 0.8N. Preferably, the binding force between the metal wire and the cells ranges from 0.2N to 0.6N. so as to secure the welding between the cells and the metal wire, to avoid sealing-off of the cells in the operation and the transferring process and performance degradation due to poor connection, and to lower the cost.

In some specific embodiments of the present disclosure, for a typical cell with a dimension of 156mm×156mm, the solar cell module has a series resistance of 380 to 440mΩ per 60 cells. The present disclosure is not limited to 60 cells, and there may be 30 cells, 72 cells, etc. When there are 72 cells, the series resistance of the solar cell module is 456 to 528mΩ, and the electrical performance of the cells is better.

In some specific embodiments of the present disclosure, for a typical cell with a dimension of 156mm×156mm, the solar cell module has an open-circuit voltage of 37.5-38.5V per 60 cells. The present disclosure is not limited to 60 cells, and there may be 30 cells, 72 cells, etc. The short-circuit current is 8.9 to 9.4A, and has nothing to do with the number of the cells.

In some specific embodiments of the present disclosure, the solar cell module has a fill factor of 0.79 to 0.82, which is independent from the dimension and number of the cells, and can affect the electrical performance of the cells.

In some specific embodiments of the present disclosure, for a typical cell with a dimension of 156mm×156mm, the solar cell module has a working voltage of 31.5-32V per 60 cells. The present disclosure is not limited to 60 cells, and there may be 30 cells, 72 cells, etc. The working current is 8.4 to 8.6A, and has nothing to do with the number of the cells.

In some specific embodiments of the present disclosure, for a typical cell with a dimension of 156mm×156mm, the solar cell module has a conversion efficiency of 16.5-17.4％, and a power of 265-280W per 60 cells.

A method for manufacturing the solar cell module 100 according to the embodiments of the present disclosure will be illustrated with respect to Fig. 7 to Fig. 9.

The method includes the steps of binding a metal wire S with a longitudinal adhesive tape 61 on a transparent film frame 60 constituted by the longitudinal adhesive tape 61 and a transverse adhesive tape 62； superposing an upper cover plate 10, a front adhesive layer 20, the transparent film frame 60, a cell 31, a back adhesive layer 40 and a back plate 50 in sequence, in which the front surface of the cell faces the front adhesive layer 20, a back surface thereof facing the back adhesive layer 40, and laminating them to obtain the solar cell module 100, the metal wire S connected with a secondary grid line 312 of a cell 31 in the cell array 30.

Alternatively, in some specific embodiments of the present disclosure, the metal wire S and the longitudinal adhesive tape 61 are bound before the metal wire S is connected with the secondary grid line 312. In some other specific embodiments of the present disclosure, the metal wire S is connected with the secondary grid line 312 when they are laminated.

In other words, when the solar cell module 100 of the present disclosure is manufactured, the conductive wires 32 are arranged in the surface of the transparent film frame 60； then the conductive wires 32 are heated (e.g. electrical heating) , such that the contact portion of the transparent film frame 60 and the conductive wires 32 is softened or melted, so as to melt and fix the conductive wires 32 and the transparent film frame 60 together, and the metal wire comes out from the transparent film frame 60.

Then, the upper cover plate 10, the front adhesive layer 20, the transparent film frame 60, the cell 31, the back adhesive layer 40 and the back plate 50 are superposed in sequence. The secondary grid lines 312 on the front surface of the cell 31 are in direct contact with the conductive wires 32. The upper cover plate 10, the front adhesive layer 20, the transparent film frame 60, the cell 31, the back adhesive layer 40 and the back plate 50 are laminated to obtain the solar cell module 100 said above in the present disclosure.

Specifically, as shown in Fig. 7, the metal wire extends reciprocally for 12 times under strain, and then melts to be connected with the transparent film frame 60. As shown in Fig. 8, a first cell 31A and a second cell 31B are prepared. As shown in Fig. 9, a front surface of the first cell 31A is connected with a metal wire, and a back surface of the second cell 31B is connected with the metal wire, so as to form a cell array 30. Fig. 9 shows two cells 31. As above, when the cell array 30 has a plurality of cells 31, the metal wire extends reciprocally to connect the front surface of the first cell 31 and the back surface of the second cell 31 adjacent to the first cell 31, i.e. connecting secondary grid lines of the first cell 31 with back electrodes of the second cell 31 by the metal wire. The metal wire extends reciprocally under strain from two clips at two ends thereof.

In the embodiment shown in Fig. 9, the adjacent cells are connected in series. As above, the adjacent cells can be connected in parallel by the metal wire in the light of practical requirements.

The cell array 30 obtained is superposed with the upper cover plate 10, the front adhesive layer 20, the back adhesive layer 40 and the back plate 50 in sequence, in which the front surface of the cell 31 faces the transparent film frame 60； the conductive wires 32 on the transparent film frame 60 are in contact with the secondary grid lines 312 on the cell 31； and the back surface of the cell 31 faces the back adhesive layer 40. Then they are laminated to obtain the solar cell module 100.

In the following, the solar cell module 100 of the present disclosure will be described with respect to specific examples.

Example 1

Example 1 is used to illustrate the solar cell module 100 according to the present disclosure and the manufacturing method thereof.

(1) Manufacturing conductive wires

An alloy layer of Sn40％-Bi55％-Pb5％ (melting point: 125℃) is attached to a surface of a copper wire, in which the copper wire has a cross section of 0.04mm², and the alloy layer has a thickness of 16μm. Hence, the conductive wires are obtained.

The conductive wires extend reciprocally, and the metal wire extends reciprocally under strain from two clips at two ends thereof, so as to form 15 parallel conductive wires. The distance between parallel adjacent conductive wires is 9.9mm.

Then part of the conductive wires are arranged in the surface of the longitudinal adhesive tape 61 of the transparent film frame 60 which is made of a transparent PET film, and has the longitudinal adhesive tape 61 and the transverse adhesive tape 62； then the conductive wires are heated, such that the contact portion of the transparent film and the conductive wires is softened or melted, so as to melt and fix the conductive wires and the transparent film together, and the metal wire comes out from the transparent film.

(2) Manufacturing a solar cell module 100

A POE adhesive layer in 1630×980×0.5mm is provided (melting point: 65℃) , and a glass plate in 1650×1000×3mm and a polycrystalline silicon cell 31 in 156×156×0.21mm are provided correspondingly. The cell 31 has 91 secondary grid lines (silver, 60μm in width, 9μm in thickness) , each of which substantially runs through the cell 31 in a longitudinal direction, and the distance between the adjacent secondary grid lines is 1.7mm. The cell 31 has five back electrodes (tin, 1.5mm in width, 10μm in thickness) on its back surface. Each back electrode substantially runs through the cell 31 in a longitudinal direction, and the distance between the adjacent back electrodes is 31mm.

60 cells are arranged in a matrix form (six rows and ten columns) . In two adjacent cells in the same row, the transparent film connected with the conductive wires by melting is disposed on a front surface of a first cell, and the secondary grid lines contact with the conductive wires. The other conductive wires which are welded extend onto a back surface of a second cell to be connected with the back electrodes on the back surface of the second cell.

Then, an upper glass plate, an upper POE adhesive layer, multiple cells arranged in a matrix form and welded with the metal wire, a lower POE adhesive layer and a lower glass plate are superposed sequentially from up to down, in which the shiny surface of the cell 31 faces the front adhesive layer 20, and the shady surface of the cell 31 faces the back adhesive layer 40, and finally they are laminated in a laminator so as to obtain the solar cell module A1.

Comparison example 1

The difference of Comparison example 1 and Example 1 lies in that the cells 31 are arranged in a matrix form. 15 metal wires connected in series are stuck on the transparent adhesive film, and then stuck on the solar cell. In two adjacent cells, the metal wire connects a front surface of a first cell and a back surface of a second cell. Then, an upper glass plate, an upper POE adhesive layer, the transparent adhesive film, multiple cells arranged in a matrix form and welded with the metal wire, the transparent adhesive film, a lower POE adhesive layer and a lower glass plate are superposed sequentially from up to down. In such a way, a solar cell module D1 is obtained.

Example 2

The solar cell module is manufactured according to the method in Example 1, but the difference compared with Example 1 lies in that a short grid line 33 (silver, 0.1mm in width) is disposed on the secondary grid line of the shiny surface of the cell 31, and is perpendicular to the secondary grid line for connecting part of the secondary grid line at the edge of the shiny surface of the cell with the conductive wire, as shown in Fig. 12, so as to obtain a solar cell module A2.

Example 3

The solar cell module is manufactured according to the method in Example 1, but the difference compared with Example 1 lies in that the cells of six columns and six rows are connected in such a manner that in two adjacent rows of cells, the conductive wires extends from a shiny surface of a cell at an end of the a^th row (a≥1) to form electrical connection with a back surface of a cell at an adjacent end of the (a+1) ^th row, so as to connect the two adjacent rows of cells. The conductive wires for connecting the two adjacent rows of cells are arranged in perpendicular to the conductive wires for connecting the adjacent cells in the two rows. In such a way, the solar cell module A3 is obtained.

Testing example 1

(1) Whether the metal wire in the solar cell module drifts is observed with the naked eyes；

(2) According to the method disclosed in IEC904-1, the solar cell modules manufactured in the above examples and the comparison example are tested with a single flash simulator under standard test conditions (STC) : 1000W/m² of light intensity, AM1.5 spectrum, and 25℃. The photoelectric conversion efficiency of each cell is recorded. The testing result is shown in Table 1.

Table 1

The fill factor refers to a ratio of the power at the maximum power point of the solar cell module and the maximum power theoretically at zero resistance, and represents the proximity of the actual power with respect to the theoretic maximum power, in which the greater the value is, the higher the photoelectric conversion efficiency is. Generally, the series resistance is small, so the fill factor is great. The photoelectric conversion efficiency refers to a ratio of converting the optical energy into electric energy by the module under a standard lighting condition (1000W/m² of light intensity) . The series resistance is equivalent to the internal resistance of the solar module, in which the greater the value is, the poorer the performance of the module is. The fill factor represents a ratio of the actual maximum power and the theoretical maximum power of the module, in which the greater the value is, the better the performance of the module is. The open-circuit voltage refers to the voltage of the module in an open circuit under a standard lighting condition. The short-circuit current refers to the current of the module in a short circuit under a standard lighting condition. The working voltage is the output voltage of the module working with the largest power under a standard lighting condition. The working current is the output current of the module working with the largest power under a standard lighting condition. The power is the maximum power which the module can reach under a standard lighting condition.

It can be indicated from Table 1 that for the solar cell module according to the embodiments of the present disclosure, the metal wire will not drift, and higher photoelectric conversion efficiency can be obtained.

In the specification, it is to be understood that terms such as “central, ” “longitudinal, ” “lateral, ” “length, ” “width, ” “thickness, ” “upper, ” “lower, ” “front, ” “rear, ” “left, ” “right, ” “vertical, ” “horizontal, ” “top, ” “bottom, ” “inner, ” “outer, ” “clockwise, ” and “counterclockwise” should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the present disclosure be constructed or operated in a particular orientation.

In addition, terms such as “first” and “second” are used herein for purposes of description and are not intended to indicate or imply relative importance or significance or to imply the number of indicated technical features. Thus, the feature defined with “first” and “second” may comprise one or more of this feature. In the description of the present disclosure, “a plurality of” means two or more than two, unless specified otherwise.

In the present disclosure, unless specified or limited otherwise, a structure in which a first feature is “on” or “below” a second feature may include an embodiment in which the first feature is in direct contact with the second feature, and may also include an embodiment in which the first feature and the second feature are not in direct contact with each other, but are contacted via an additional feature formed therebetween. Furthermore, a first feature “on, ” “above, ” or “on top of” a second feature may include an embodiment in which the first feature is right or obliquely “on, ” “above, ” or “on top of” the second feature, or just means that the first feature is at a height higher than that of the second feature； while a first feature “below, ” “under, ” or “on bottom of” a second feature may include an embodiment in which the first feature is right or obliquely “below, ” “under, ” or “on bottom of” the second feature, or just means that the first feature is at a height lower than that of the second feature.

Reference throughout this specification to “an embodiment, ” “some embodiments, ” or “some examples” means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. Thus, these terms throughout this specification do not necessarily refer to the same embodiment or example of the present disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

Although embodiments of the present disclosure have been shown and described, it would be appreciated by those skilled in the art that changes, modifications, alternatives and variations can be made in the embodiments without departing from the scope of the present disclosure.

Claims

A solar cell module, comprising an upper cover plate, a front adhesive layer, a transparent film frame, a cell array, a back adhesive layer and a back plate superposed in sequence, the cell array including a plurality of cells and conductive wires connected with secondary grid lines on the cells, two adjacent cells being connected by the conductive wires, the transparent film frame constituted by a longitudinal adhesive tape and a transverse adhesive tape intersected with each other, and the conductive wire formed with a metal wire and bonded with the longitudinal adhesive tape.
The solar cell module according to claim 1, wherein the longitudinal adhesive tape and the transverse adhesive tape are connected or integrated by an adhesive or melting in a position where they are intersected.
The solar cell module according to claim 1, wherein the metal wire is coated with an alloy layer.
The solar cell module according to claim 3, wherein the metal wire has a diameter of 0.05 to 0.5mm.
The solar cell module according to claim 4, wherein the metal wire has a diameter of 0.15 to 0.25mm.
The solar cell module according to any one of claims 1 to 5, wherein the metal wire is a copper wire.
The solar cell module according to any one of claims 1 to 6, wherein the transverse adhesive tape has a width of 0.1 to 5mm.
The solar cell module according to claim 7, wherein the transverse adhesive tape has a width of 0.5 to 2mm.
The solar cell module according to any one of claims 1 to 8, wherein there are 1 to 10 transverse adhesive tapes.
The solar cell module according to claim 9, wherein there are 2 to 4 transverse adhesive tapes.
The solar cell module according to any one of claims 1 to 10, wherein the transverse adhesive tape has a thickness of 0.05 to 0.5mm.
The solar cell module according to claim 11, wherein the transverse adhesive tape has a thickness of 0.1 to 0.2mm.
The solar cell module according to any one of claims 1 to 12, wherein the longitudinal adhesive tape has a width of 0.5 to 5mm.
The solar cell module according to claim 13, wherein the longitudinal adhesive tape has a width of 1 to 3mm.
The solar cell module according to any one of claims 1 to 14, wherein there are 2 to 10 longitudinal adhesive tapes.
The solar cell module according to claim 15, wherein there are 2 to 4 longitudinal adhesive tapes.
The solar cell module according to any one of claims 1 to 16, wherein the longitudinal adhesive tape has a thickness of 0.05 to 0.5mm.
The solar cell module according to claim 17, wherein the longitudinal adhesive tape has a thickness of 0.1 to 0.2mm.
The solar cell module according to any one of claims 1 to 18, wherein there are multiple cells in the cell array, adjacent cells connected by the metal wire that extends reciprocally between a surface of a first cell of the adjacent cells and a surface of a second cell thereof.
The solar cell module according to claim 19, wherein the metal wire extends reciprocally between a front surface of the first cell and a back surface of the second cell.
The solar cell module according to claim 19, wherein a back electrode is disposed on the back surface of the second cell, and the metal wire is welded with the back electrode of the second cell.
The solar cell module according to any one of claims 19 to 21, wherein the metal wire extends reciprocally between the front surface of the first cell and the back surface of the second cell for 10 to 60 times.
The solar cell module according to any one of claims 19 to 21, wherein a distance between two adjacent conductive wires ranges from 2.5mm to 15mm.
The solar cell module according to any one of claims 19 to 21, wherein the two adjacent conductive wires form a U-shape structure or a V-shape structure.
The solar cell module according to claim 19, wherein the cells are arranged in an n×m matrix form, n representing a column, and m representing a row；

in a row of cells, the metal wire extends reciprocally between a surface of a first cell and a surface of a second cell adjacent to the first cell； in two adjacent rows of cells, the metal wire extends reciprocally between a surface of a cell in a a^th row and a surface of a cell in a (a+1) ^th row； and m-1≥a≥1.
The solar cell module according to claim 25, wherein in two adjacent rows of cells, the metal wire extends reciprocally between a surface of a cell at an end of the a^th row and a surface of a cell at an end of the (a+1) ^th row, the end of the a^th row and the end of the (a+1) ^th row located at the same side of the matrix form.
The solar cell module according to claim 25, wherein in a row of cells, the metal wire extends reciprocally between a front surface of a first cell and a back surface of a second cell adjacent to the first cell；

in two adjacent rows of cells, the metal wire extends reciprocally between a front surface of a cell at an end of the a^th row and a back surface of a cell at an end of the (a+1) ^th row, to connect the two adjacent rows of cells in series.
The solar cell module according to any one of claims 25 to 27, wherein there is a metal wire extending reciprocally between adjacent cells in a row； and there is a metal wire extending reciprocally between cells in adjacent rows.
The solar cell module according to claim 19, wherein there is a metal wire.
The solar cell module according to any one of claims 19 to 29, wherein the metal wire is coated with a welding layer, and a ratio of a thickness of the welding layer and a diameter of the metal wire is (0.02-0.5) : 1.
The solar cell module according to claim 30, wherein the welding layer contains Sn, and at least one of Bi, In, Ag, Sb, Pb and Zn.
The solar cell module according to claim 30, wherein the welding layer contains Sn, Bi, and at least one of In, Ag, Sb, Pb and Zn.
A method for manufacturing a solar cell module according to claims 1 to 32, comprising:

binding a metal wire with a longitudinal adhesive tape on a transparent film frame constituted by the longitudinal adhesive tape and a transverse adhesive tape；

superposing an upper cover plate, a front adhesive layer, the transparent film frame, a cell array, a back adhesive layer and a back plate in sequence, in which the front surface of the cell faces the front adhesive layer, a back surface thereof facing the back adhesive layer, and laminating them to obtain the solar cell module, the metal wire connected with a secondary grid line of a cell in the cell array.
The method according to claim 33, wherein the metal wire and the longitudinal adhesive tape are bound before the metal wire is connected with the secondary grid line.
The method according to claim 33, wherein the metal wire is connected with the secondary grid line when they are laminated.