KR102619351B1 - Solar cell module - Google Patents

Abstract

The present invention relates to solar cell modules.
A solar cell module according to an example of the present invention includes a semiconductor substrate, a plurality of solar cells each provided with a first electrode and a second electrode on the back of the semiconductor substrate, and positioned adjacent to each other in a first direction; and a plurality of first conductive wires connected to the rear surface of the first electrode and a plurality of second conductive wires connected to the rear surface of the second electrode, and a plurality of solar cells connected to the first solar cell among the plurality of solar cells. 1 Each conductive wire is connected to overlap each of a plurality of second conductive wires connected to a second solar cell immediately adjacent to the first solar cell.

Description

Solar cell module {SOLAR CELL MODULE}

The present invention relates to solar cell modules.

Recently, as the depletion of existing energy resources such as oil and coal is predicted, interest in alternative energy to replace them is increasing, and solar cells that produce electrical energy from solar energy are receiving attention.

A typical solar cell includes semiconductor parts that form a p-n junction by different conductivity types, such as p-type and n-type, and electrodes respectively connected to the semiconductor parts of different conductivity types.

When light is incident on such a solar cell, a plurality of electron-hole pairs are generated in the semiconductor part, and the generated electron-hole pairs are separated into charged electrons and holes, so that the electrons move toward the n-type semiconductor part and the holes are p Move to the semiconductor section of the older brother. The moved electrons and holes are collected by different electrodes connected to the n-type semiconductor part and the p-type semiconductor part, respectively, and power is obtained by connecting these electrodes with wires.

Meanwhile, the conventional solar cell module had a structure in which a separate conductive wire was connected to the electrode of the solar cell as described above, and then an interconnector was connected to the conductive wire to connect the solar cells in series.

However, in this case, during the heat treatment process to connect the conductive wire and the interconnector, the interconnector bends due to the thermal expansion stress of the conductive wire, which causes the gap between the conductive wire and the interconnector to detach, causing the module to There was a problem that the output of the device deteriorated.

The purpose of the present invention is to provide a solar cell module.

A solar cell module according to an example of the present invention includes a semiconductor substrate, a plurality of solar cells each provided with a first electrode and a second electrode on the back of the semiconductor substrate, and positioned adjacent to each other in a first direction; and a plurality of first conductive wires connected to the rear surface of the first electrode and a plurality of second conductive wires connected to the rear surface of the second electrode, and a plurality of solar cells connected to the first solar cell among the plurality of solar cells. 1 Each conductive wire is connected to overlap each of a plurality of second conductive wires connected to a second solar cell immediately adjacent to the first solar cell.

Here, the wiring connection portion in which each of the first conductive wires connected to the first solar cell and each of the second conductive wires connected to the second solar cell overlap each other and is connected to the semiconductor substrate of the first solar cell and the second solar cell. It can be located between semiconductor substrates.

Additionally, in the wire connection portion, one of the first conductive wires or the second conductive wires may be connected to the rear surface of the other conductive wires.

In addition, the width in the first direction where the first and second conductive wires overlap at the wire connection portion is larger than the line width of each of the first and second conductive wires, and the width between the semiconductor substrate of the first solar cell and the semiconductor substrate of the second solar cell is larger than the line width of each of the first and second conductive wires. It may be smaller than the separation distance.

In addition, the sum of the thicknesses of the first and second conductive wires connected to each other at the wire connection portion may be greater than the thickness of the portion of the first and second conductive wires that overlaps the projection surface of the semiconductor substrate of the first and second solar cells.

In addition, each of the first and second electrodes is arranged long in a second direction crossing the first direction, and each of the first and second conductive wires is arranged long in a first direction crossing the first and second electrodes on the rear surface of the semiconductor substrate. It can be.

Here, the first conductive wiring is connected to the first electrode by a first conductive adhesive at the portion where it intersects the first electrode, is insulated from the second electrode by an insulating layer at the portion where it intersects the second electrode, and is insulated from the second electrode by an insulating layer. The wiring may be connected to the second electrode by a first conductive adhesive at a portion where it intersects the second electrode, and may be insulated from the first electrode by an insulating layer that intersects the first electrode.

Here, each of the first conductive wires connected to the first solar cell and each of the second conductive wires connected to the second solar cell may be located on the same line in the first direction.

In addition, the first conductive wires and the second conductive wires in the wire connection portion may be connected to each other using a second conductive adhesive.

Here, the melting point of the second conductive adhesive is higher than the melting point of the first conductive adhesive and may be 200°C or lower.

Additionally, in the wire connection portion, the first conductive wires and the second conductive wires may be connected by physically contacting each other in an overlapping state.

Additionally, each of the first and second conductive wires may be provided with a stress reduction unit that reduces thermal expansion stress of each of the first and second conductive wires between the semiconductor substrates of the first and second solar cells and the wire connection unit.

Here, the stress reduction unit has a shape in which each of the first and second conductive wires is curved in the second direction on the plane of the solar cell module, has a shape curved in the thickness direction of the solar cell module, or is connected to the first and second conductive wires. It may be provided in the form of a slit.

In addition, the length of each of the first and second conductive wires in the first direction may be longer than the length of the semiconductor substrate in the first direction and may be smaller than the sum of the length of the first direction of the semiconductor substrate and the distance between the solar cells.

In the solar cell module according to an example of the present invention, each of the plurality of first conductive wires connected to the first solar cell is connected and overlaps each of the plurality of second conductive wires connected to the second solar cell immediately adjacent to the first solar cell. By doing so, the output of the solar cell module can be further improved and manufacturing costs can be further reduced.

1 is a diagram for explaining the entire front plan view of a solar cell module according to an example of the present invention.
FIG. 2 is a diagram for explaining a cross-sectional view of the solar cell module shown in FIG. 1.
Figure 3 is an example showing the front surfaces of first and second solar cells C1 and C2 connected in series with each other according to an example of the present invention.
Figure 4 is an example showing the front and back sides of the first and second solar cells C1 and C2 connected in series with each other.
FIG. 5 is a partial perspective view showing an example of a solar cell applied to the present invention, and FIG. 6 shows a cross section in the first direction (x) of the solar cell shown in FIG. 5.
FIG. 7 shows a cross section along line X1-X1 in FIGS. 3 and 4.
FIG. 8 is a diagram for explaining in more detail the structure of the wiring connection part in FIG. 3.
FIG. 9 is a diagram for explaining a first modified example in which the first and second conductive wires 210 and 220 between the first and second solar cells in the solar cell module shown in FIG. 8 are provided with stress reduction units.
FIG. 10 is a diagram for explaining a second modified example in which the first and second conductive wires 210 and 220 between the first and second solar cells in the solar cell module shown in FIG. 8 are provided with a stress reduction unit.
FIG. 11 is a diagram for explaining a third modified example in which the first and second conductive wires 210 and 220 between the first and second solar cells in the solar cell module shown in FIG. 8 are provided with a stress reduction unit.

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts not related to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

In the drawing, the thickness is enlarged to clearly express various layers and regions. When a part of a layer, membrane, region, plate, etc. is said to be "on" another part, this includes not only being "directly above" the other part, but also parts in between. Conversely, when a part is said to be “right on top” of another part, it means that there is no other part in between. Also, when a part is said to be formed “wholly” on top of another part, it means not only that it is formed on the entire surface of the other part, but also that some of the edges are not formed.

Hereinafter, the front may be one side of the semiconductor substrate on which direct light is incident, and the back may be the opposite side of the semiconductor substrate on which direct light is not incident or on which reflected light rather than direct light may be incident.

In addition, hereinafter, a cell string refers to a structure or form in which a plurality of solar cells are connected in series.

In addition, the fact that the thickness or width of a certain component part is the same as the thickness or width of another component part means that it is the same within a range of 10%, including process error.

FIG. 1 is a diagram for explaining the entire front plan view of a solar cell module according to an example of the present invention, and FIG. 2 is a diagram for explaining a cross-sectional view of the solar cell module shown in FIG. 1 .

As shown in Figures 1 and 2, the solar cell module according to an example of the present invention includes a plurality of solar cells and a plurality of first and second conductive elements connected to the back of each of the plurality of solar cells and connecting the solar cells in series. Wiring (210, 220) is provided.

In addition, a front transparent substrate 10, fillers 20 and 30, a back sheet 40 and a frame 50 that encapsulate a cell string in which a plurality of solar cells are connected in series may be further provided.

Here, the plurality of solar cells may include a semiconductor substrate 110 and a plurality of first electrodes 141 and second electrodes 142 on the rear surface of the semiconductor substrate 110. Such a plurality of solar cells will be described in more detail below in FIG. 5.

As shown in FIGS. 1 and 2 , the first and second conductive wires 210 and 220 may be connected to the back of each solar cell. Here, the plurality of first conductive wires 210 may be connected to each of the plurality of first electrodes 141 formed on the back of each solar cell, and the plurality of second conductive wires 220 may be connected to each of the plurality of first electrodes 141 formed on the back of each solar cell. It can be connected to each of the plurality of second electrodes 142 formed.

In this way, among the plurality of solar cells to which the plurality of first and second conductive wirings 210 and 220 are connected, each of the plurality of first conductive wirings 210 connected to the first solar cell C1 is a first solar cell ( A cell string may be formed by overlapping and connecting each of the plurality of second conductive wires 220 connected to the second solar cell C2 immediately adjacent to C1).

As shown in FIG. 2, such a cell string may be heat-compressed and laminated while placed between the front transparent substrate 10 and the rear sheet 40.

For example, a plurality of solar cells are disposed between the front transparent substrate 10 and the back sheet 40, and transparent fillers 20 and 30, such as an EVA sheet, are disposed on the front and back of all the plurality of solar cells. In, it can be integrated and encapsulated by a lamination process in which heat and pressure are applied simultaneously.

In addition, as shown in FIG. 1, the front transparent substrate 10, the rear sheet 40, and the fillers 20 and 30 encapsulated through the lamination process can be protected by being fixed at the edges by the frame 50. .

Therefore, as shown in FIG. 1, the front transparent substrate 10 and the fillers 20 and 30 are transmitted through the front of the solar cell module, and a plurality of solar cells and a plurality of first and second conductive wires 210 and 220 are formed. ), the rear seat 40 and the frame 50 can be seen.

In addition, each of the cell strings may be positioned long in the first direction (x) and arranged to be spaced apart in the second direction (y), and such a plurality of cell strings may have a busing bar extending long in the second direction (y). 310) can be connected in series in the second direction (y).

Here, the front transparent substrate 10 may be formed of tempered glass, etc., which has high transmittance and excellent damage prevention function.

The rear sheet 40 can protect the solar cells from the external environment by preventing moisture from penetrating from the rear of the solar cells C1 and C2. This back sheet 40 may have a multi-layer structure, such as a layer that prevents moisture and oxygen penetration and a layer that prevents chemical corrosion.

This back sheet 40 is made of a thin sheet made of an insulating material such as FP (fluoropolymer) / PE (polyaster) / FP (fluoropolymer), but may be an insulating sheet made of another insulating material.

This lamination process may be performed with planar-shaped fillers 20 and 30 disposed between the front transparent substrate 10 and the solar cell and between the solar cell and the rear substrate.

Here, the material of the fillers 20 and 30 may be formed of a material different from that of the insulating layer 252, and prevents corrosion due to moisture penetration and protects the solar cells (C1 and C2) from impact. It can be made of a material such as ethylene vinyl acetate (EVA) that can absorb shock.

Accordingly, the planar-shaped fillers 20 and 30 disposed between the front transparent substrate 10 and the solar cell and between the solar cell and the rear substrate may be softened and hardened by heat and pressure during the lamination process.

Meanwhile, in such a solar cell module, as shown in FIG. 2, each of the plurality of first conductive wires 210 connected to the first solar cell C1 among the plurality of solar cells is connected to the first solar cell C1. may be connected to each other by overlapping with the plurality of second conductive wires 220 connected to the second solar cell C2 immediately adjacent thereto.

At this time, for example, the first conductive wiring 210 fixed to the first solar cell C1 may have a straight portion that protrudes outside the projection area of the semiconductor substrate 110 and is connected to the second solar cell C2. The portion of the fixed second conductive wiring 220 that protrudes outside the projection area of the semiconductor substrate 110 may be bent toward the back of the first conductive wiring 210 .

Accordingly, as shown in FIG. 2, the front side of the second conductive wiring 220 fixed to the second solar cell C2 is on the rear side of the first conductive wiring 210 fixed to the first solar cell C1. These can be nested and connected.

In this way, the structure in which the first conductive wire 210 connected to the first solar cell C1 and the second conductive wire 220 connected to the second solar cell C2 are overlapped and connected to each other is a separate interconnector. Since it does not use , the structural stability of the module can be further improved.

For example, in a structure in which solar cells are connected in series by connecting an interconnector to a conductive wire, the interconnector is bent during the heat treatment process to connect the conductive wire and the interconnector, which causes a gap between the conductive wire and the interconnector. There is a problem that the output of the module becomes abnormal or deteriorates due to the desorption phenomenon.

However, as in the present invention, in the structure of overlapping and connecting the plurality of first and second conductive wirings 210 and 220, the plurality of first conductive wirings 210 and the plurality of second conductive wirings 220 are common. Since a separate in-connector connected to the interconnector is not used, the detachment phenomenon between the conductive wiring and the interconnector as described above can be fundamentally eliminated. Accordingly, the output of the solar cell module can be further improved.

In addition, since the plurality of first conductive wires 210 connected to the first solar cell C1 and the plurality of second conductive wires 220 connected to the second solar cell C2 are directly connected without a separate interconnector. , the manufacturing cost of the module can be further reduced, and even if a connection defect is found in some solar cells during the module manufacturing process, the solar cell can be replaced more easily, thereby improving the module process yield. .

The structure in which the plurality of first conductive wires 210 connected to the first solar cell C1 and the plurality of second conductive wires 220 connected to the second solar cell C2 are connected to each other is the overall structure of the solar cell module. After first explaining the structure, it is explained in more detail in Figure 8 below.

FIG. 3 is an example showing the front surfaces of the first and second solar cells C1 and C2 connected in series, according to an example of the present invention, and FIG. 4 shows the front surfaces of the first and second solar cells C1 and C2 connected in series with each other, according to an example of the present invention. This is an example showing the front and back.

As shown in Figures 3 and 4, in the solar cell module according to the present invention, the first and second conductive wires 210 and 220 may be connected to the back of the semiconductor substrate 110 provided in each solar cell. .

Here, the plurality of solar cells C1 and C2 may be arranged to be spaced apart in the first direction (x), and each of the plurality of solar cells C1 and C2 may be connected to at least the semiconductor substrate 110 and the semiconductor substrate 110. It may be provided with a plurality of first electrodes 141 and a plurality of second electrodes 142 spaced apart from each other on the rear surface and extending long in the second direction (y) intersecting the first direction (x).

In addition, the plurality of first and second conductive wires 210 and 220 are arranged to extend long in the first direction (x), which is the arrangement direction of the first and second solar cells C1 and C2, and are connected to each of the plurality of solar cells. It can be.

Here, the first direction (x) length of each of the first and second conductive wires 210 and 220 is longer than the maximum length in the first direction (x) of the semiconductor substrate 110, and the first direction (x) of the semiconductor substrate 110 x) may be smaller than the sum of the maximum length and the spacing between the first and second solar cells (C1, C2).

More specifically, the length of each of the first and second conductive wires 210 and 220 in the first direction (x) may be between 1 and 1.2 times the maximum length of the semiconductor substrate 110 in the first direction (x).

In this way, by relatively shortening the length of each of the first and second conductive wires 210 and 220 in the first direction (x), the thermal expansion stress of the first and second conductive wires 210 and 220 can be further reduced.

As such, the plurality of first and second conductive wires 210 and 220 are connected to the plurality of first electrodes 141 provided in each of the first and second solar cells C1 and C2 by crossing and overlapping. It may include a plurality of second conductive wires 220 connected to the first conductive wire 210 and the plurality of second electrodes 142 by crossing and overlapping.

More specifically, the plurality of first conductive wires 210 are connected to the plurality of first electrodes 141 provided in each of the plurality of solar cells C1 and C2 through a first conductive adhesive 251 made of a conductive material. , may be insulated from the plurality of second electrodes 142 by an insulating layer 252 made of an insulating material.

In addition, the plurality of second conductive wires 220 are connected to the plurality of second electrodes 142 provided in each of the plurality of solar cells C1 and C2 through the first conductive adhesive 251, and the insulating layer 252 ) may be insulated from the plurality of first electrodes 141.

The first and second conductive wires 210 and 220 are made of a conductive metal material and include a conductive core containing any one of gold (Au), silver (Ag), copper (Cu), or aluminum (Al), The surface of the core CR may be coated and may include a conductive coating layer containing tin (Sn) or an alloy containing tin (Sn).

Here, among both ends of the first conductive wire 210 connected to the first solar cell C1, the end connected to the second conductive wire 220 connected to the second solar cell C2 is the semiconductor substrate 110. It is located outside the projection area and may protrude in the direction of the second solar cell C2.

In addition, among both ends of the second conductive wire 220 connected to the second solar cell C2, the end connected to the first conductive wire 210 connected to the first solar cell C1 is connected to the semiconductor substrate 110. It is located outside the projection area and may protrude in the direction of the first solar cell C1.

In this way, the first conductive wiring 210 connected to the first solar cell C1 and the second conductive wiring 220 connected to the second solar cell C2 are connected to the first and second semiconductor substrates 110 facing each other. ) may protrude out of the projection area and be connected, and accordingly, the first and second solar cells may be connected in series to each other in the first direction (x).

Here, each of the first conductive wires 210 connected to the first solar cell C1 and each of the second conductive wires 220 connected to the second solar cell C2 are shown in FIGS. 3 and 4. As shown, they may be located on the same line.

That is, the second conductive wires 220 connected to the second solar cell C2 may be located on extension lines of each of the first conductive wires 210 connected to the first solar cell C1.

In this way, the first conductive wires 210 of the first solar cell C1 and the second conductive wires 220 of the second solar cell C2 are positioned on the same line, so that the first solar cell C1 During the heat treatment process of connecting the first conductive wires 210 of (C1) and the second conductive wires 220 of the second solar cell (C2) to each other, the first and second conductive wires 210 and 220 are formed by a thermal expansion coefficient. ) is thermally expanded, the possibility that the first and second conductive wires 210 and 220 are not connected to each other and are separated can be further minimized.

As such, a method of positioning the first conductive wires 210 of the first solar cell C1 and the second conductive wires 220 of the second solar cell C2 on the same line is as follows, for example: We can do it together.

As a first example, the first and second electrodes 141 and 142 are formed in the same pattern on the rear surfaces of the first and second solar cells C1 and C2, and the first conductive adhesive 251 and the insulating layer 252 are formed. After forming the same pattern on the back of each of the first and second solar cells (C1, C2), the first and second conductive wires (210, 220) are fixed to the back of the first and second solar cells (C1, C2). In order to connect the first and second conductive wires 210 and 220 to each other, the first conductive wires 210 are adjacent to the fixed first solar cell C1 in the first direction (x) and connect the second conductive wires 210 and 220 to each other. The second solar cell C2 to which the conductive wires 220 are fixed may be placed by rotating the second solar cell C2 to which the second conductive wires 220 are fixed by 180° on a plane.

Accordingly, as shown in FIGS. 3 and 4, the first conductive wires 210 of the first solar cell C1 and the second conductive wires 220 of the second solar cell C2 are identical to each other. It can be located on the line.

As a second example, after forming the first and second electrodes 141 and 142 in the same pattern on the rear surfaces of the first and second solar cells C1 and C2, the first conductive adhesive 251 and the insulating layer 252 are formed. When forming on the back of a semiconductor substrate, the positions of the first and second solar cells C1 and C2 may be reversed.

That is, the positions of the first conductive adhesive 251 and the insulating layer 252 formed on the back of the first solar cell (C1) are the positions of the first conductive adhesive 251 and the insulating layer 252 formed on the back of the second solar cell (C2). The position of the insulating layer 252 may be opposite to that of the insulating layer 252.

For example, the position where the first conductive adhesive 251 is formed on the back of the first solar cell (C1) may be the same as the position where the insulating layer 252 is formed on the back of the second solar cell (C2), The position where the insulating layer 252 is formed on the back of the first solar cell (C1) may be the same as the position where the first conductive adhesive 251 is formed on the back of the second solar cell (C2).

In this way, after forming the first conductive adhesive 251 and the insulating layer 252 at opposite positions on the rear surfaces of the first and second solar cells C1 and C2, respectively, the first and second conductive wirings 210, 220) is fixed to the back of the first and second solar cells C1 and C2, the first solar cell C1 and the second conductive wires 220 to which the first conductive wires 210 are fixed are When the fixed second solar cell C2 is arranged in the first direction (x), as shown in FIGS. 3 and 4, the first conductive wires 210 of the first solar cell C1 and the second The second conductive wires 220 of the solar cell C2 may be located on the same line.

Considering the cost of the manufacturing process, the first example may be more effective.

Here, each component part of the solar cell shown in FIGS. 3 and 4 will be described in more detail as follows.

FIG. 5 is a partial perspective view showing an example of a solar cell applied to the present invention, and FIG. 6 shows a cross section in the first direction (x) of the solar cell shown in FIG. 5.

As shown in Figures 5 and 6, an example of a solar cell according to the present invention includes an anti-reflection film 130, a semiconductor substrate 110, a tunnel layer 180, a first semiconductor unit 121, and a second semiconductor unit. (172), an intrinsic semiconductor portion 150, a passivation layer 190, a plurality of first electrodes 141, and a plurality of second electrodes 142 may be provided.

Here, the anti-reflection layer 130, the tunnel layer 180, and the passivation layer 190 may be omitted, but since the efficiency of the solar cell is further improved when provided, the case where they are provided will be described as an example below.

The semiconductor substrate 110 may be formed of at least one of single crystal silicon and polycrystalline silicon doped with impurities of the first conductivity type or the second conductivity type. For example, the semiconductor substrate 110 may be formed of a single crystal silicon wafer.

Here, the first conductivity type impurity or the second conductivity type impurity contained in the semiconductor substrate 110 may be either an n-type or a p-type conductivity type.

When the semiconductor substrate 110 has a p-type conductivity type, impurities of trivalent elements such as boron (B), gallium, indium, etc. are doped into the semiconductor substrate 110. However, when the semiconductor substrate 110 has an n-type conductivity type, impurities of pentavalent elements such as phosphorus (P), arsenic (As), antimony (Sb), etc. may be doped into the semiconductor substrate 110.

Hereinafter, the case where the impurities contained in the semiconductor substrate 110 are impurities of the second conductivity type and are n-type will be described as an example. However, it is not necessarily limited to this.

The front surface of the semiconductor substrate 110 may have a plurality of uneven surfaces. Because of this, the first semiconductor portion 121 located on the front surface of the semiconductor substrate 110 may also have an uneven surface.

Because of this, the amount of light reflected from the front of the semiconductor substrate 110 may decrease, and the amount of light incident into the semiconductor substrate 110 may increase.

The anti-reflection film 130 is located on the front surface of the semiconductor substrate 110 to minimize reflection of light incident on the front surface of the semiconductor substrate 110 from the outside, and is made of aluminum oxide (AlOx), silicon nitride (SiNx), and silicon. It may be formed of at least one of an oxide film (SiOx) and a silicon oxynitride film (SiOxNy).

The tunnel layer 180 is disposed in direct contact with the entire rear surface of the semiconductor substrate 110 and may include a dielectric material. Accordingly, the tunnel layer 180 can pass carriers generated in the semiconductor substrate 110, as shown in FIGS. 5 and 6.

Such a tunnel layer 180 allows carriers generated in the semiconductor substrate 110 to pass through and may perform a passivation function for the rear surface of the semiconductor substrate 110.

In addition, the tunnel layer 180 may be formed of a dielectric material such as SiCx or SiOx, which is highly durable even in high temperature processes of 600°C or higher.

As shown in FIGS. 5 and 6, the first semiconductor portion 121 is disposed on the rear surface of the semiconductor substrate 110. For example, the first semiconductor portion 121 may be disposed in direct contact with a portion of the rear surface of the tunnel layer 180. .

In addition, the first semiconductor portion 121 is disposed on the rear surface of the semiconductor substrate 110 in the second direction (y) and may be formed of a polycrystalline silicon material having a first conductivity type opposite to the second conductivity type. there is.

Here, the first semiconductor portion 121 may be doped with an impurity of the first conductivity type, and when the impurity contained in the semiconductor substrate 110 is an impurity of the second conductivity type, the first semiconductor portion 121 may be doped with an impurity of the second conductivity type. A p-n junction can be formed with the semiconductor substrate 110 with the layer 180 interposed therebetween.

Since each first semiconductor portion 121 forms a p-n junction with the semiconductor substrate 110, the first semiconductor portion 121 may have a p-type conductivity type, and the plurality of first semiconductor portions 121 may have a p-n junction. When it has a conductivity type, the first semiconductor portion 121 may be doped with an impurity of a trivalent element.

The second semiconductor unit 172 is disposed on the rear surface of the semiconductor substrate 110, extending long in the second direction (y) parallel to the first semiconductor unit 121. For example, the second semiconductor unit 172 is disposed on the rear surface of the tunnel layer 180. 1 It may be formed by directly contacting a partial area spaced apart from each of the semiconductor units 121.

The second semiconductor portion 172 may be formed of a polycrystalline silicon material doped with impurities of the second conductivity type at a higher concentration than the semiconductor substrate 110 . Therefore, for example, when the semiconductor substrate 110 is doped with an n-type impurity, which is a second conductivity type impurity, the plurality of second semiconductor portions 172 may be n+ impurity regions.

This second semiconductor portion 172 prevents the movement of holes toward the second semiconductor portion 172, which is the direction of electron movement, due to a potential barrier caused by the difference in impurity concentration between the semiconductor substrate 110 and the second semiconductor portion 172. On the other hand, movement of carriers (eg, electrons) toward the second semiconductor portion 172 can be facilitated.

Therefore, the amount of charge lost due to recombination of electrons and holes in the second semiconductor portion 172 and its vicinity or the first and second electrodes 141 and 142 is reduced and electron movement is accelerated to form the second semiconductor portion 172. The amount of electron transfer to can be increased.

5 and 6 so far, the case where the semiconductor substrate 110 is an impurity of the second conductivity type is explained as an example, and the first semiconductor portion 121 serves as an emitter portion and the second semiconductor portion 172 ) serves as a rear electric field as an example.

However, differently from this, when the semiconductor substrate 110 contains impurities of the first conductivity type, the first semiconductor portion 121 serves as a rear electric field portion, and the second semiconductor portion 172 serves as an emitter portion. You can also do this.

In addition, in FIGS. 5 and 6 herein, the case where the first semiconductor portion 121 and the second semiconductor portion 172 are formed of a polycrystalline silicon material on the rear surface of the tunnel layer 180 has been described as an example. However, differently from this, the tunnel When the layer 180 is omitted, the first semiconductor portion 121 and the second semiconductor portion 172 may be doped by diffusion of impurities into the rear surface of the semiconductor substrate 110. In this case, the first semiconductor unit 121 and the second semiconductor unit 172 may be formed of the same single crystal silicon material as the semiconductor substrate 110.

As shown in FIGS. 5 and 6, the intrinsic semiconductor portion 150 may be formed on the rear surface of the tunnel layer 180 exposed between the first semiconductor portion 121 and the second semiconductor portion 172, Unlike the first semiconductor portion 121 and the second semiconductor portion 172, the intrinsic semiconductor portion 150 may be formed of an intrinsic polycrystalline silicon layer that is not doped with impurities of the first conductivity type or impurities of the second conductivity type. You can.

In addition, as shown in FIGS. 5 and 6, each of both sides of the intrinsic semiconductor unit 150 may have a structure in direct contact with the side surface of the first semiconductor unit 121 and the side surface of the second semiconductor unit 172. there is.

The passivation layer 190 is a defect caused by a dangling bond formed on the back side of the polycrystalline silicon material layer formed in the first semiconductor portion 121, the second semiconductor portion 172, and the intrinsic semiconductor portion 150. By removing, it can serve to prevent carriers generated from the semiconductor substrate 110 from being recombined by dangling bonds and disappearing.

The plurality of first electrodes 141 may be connected to the first semiconductor portion 121 and may be formed to extend long in the second direction (y). In this way, the first electrode 141 can collect carriers, for example, holes, that have moved toward the first semiconductor portion 121.

The plurality of second electrodes 142 may be connected to the second semiconductor portion 172 and may be formed to extend in a second direction (y) parallel to the first electrode 141 . As such, the second electrode 142 can collect carriers, for example, electrons, that have moved toward the second semiconductor portion 172.

As shown in FIG. 1, the first electrode 141 and the second electrode 142 may be alternately arranged in the first direction (x).

In the solar cell according to the present invention manufactured with this structure, the holes collected through the first electrode 141 and the electrons collected through the second electrode 142 can be used as power for an external device through an external circuit device. You can.

The solar cell applied to the solar cell module according to the present invention is not necessarily limited to FIGS. 5 and 6, and the first and second electrodes 141 and 142 provided in the solar cell are formed only on the back of the semiconductor substrate 110. Except for, other components can be changed at any time.

For example, in the solar cell module of the present invention, a portion of the first electrode 141 and the first semiconductor portion 121 are located on the front surface of the semiconductor substrate 110, and a portion of the first electrode 141 is located on the semiconductor substrate 110. ) A MWT type solar cell connected to the remaining part of the first electrode 141 formed on the back of the semiconductor substrate 110 through a hole formed in the semiconductor substrate 110 can also be applied.

The cross-sectional structure of such a solar cell connected in series by the first and second conductive wires 210 and 220 is shown in FIG. 7 below.

FIG. 7 shows a cross section along line X1-X1 in FIGS. 3 and 4.

As shown in FIG. 7 , a plurality of solar cells including the first solar cell C1 and the second solar cell C2 may be arranged in the first direction (x). At this time, the longitudinal direction of the plurality of first and second electrodes 141 and 142 provided in the first and second solar cells C1 and C2 will be arranged to face the second direction (y) as shown in FIGS. 4 and 5. You can.

Here, the plurality of first and second conductive wires 210 and 220 may have a conductive wire shape with a circular cross-section or a ribbon shape whose width is greater than the thickness.

Here, the line widths W210 and W220 of each of the first and second conductive wires 210 and 220 shown in FIGS. 4 and 7 are considered to minimize manufacturing costs while keeping the line resistance of the conductive wires sufficiently low, It can be formed between 0.5mm and 2.5mm, and the gap between the first conductive wiring 210 and the second conductive wiring 220 is determined by considering the total number of the first and second conductive wirings 210 and 220, so that the solar cell It can be formed between 4mm and 6.5mm to prevent short-circuit current of the module from being damaged.

In this way, the number of first and second conductive wires 210 and 220 connected to one solar cell may be 10 to 20, respectively. Accordingly, the total number of first and second conductive wires 210 and 220 connected to one solar cell may be 20 to 40.

As described above in FIG. 1, the first and second conductive wires 210 and 220 are formed by applying a first conductive adhesive to the first and second electrodes 141 and 142 formed on the back of the semiconductor substrate 110 of each solar cell. It may be connected through (251) or insulated by the insulating layer (252).

Here, the first conductive adhesive 251 may be formed of a metal material containing tin (Sn) or an alloy containing tin (Sn). In addition, this first conductive adhesive 251 is formed in the form of a solder paste containing tin (Sn) or an alloy containing tin (Sn), or tin (Sn) or tin (Sn) in epoxy. ) may be formed in the form of an epoxy solder paste or conductive paste containing an alloy containing.

Here, the insulating layer 252 may be made of any insulating material. For example, any one of epoxy-based, polyimide, polyethylene, acrylic-based, or silicon-based insulating materials may be used.

In this way, with the first and second solar cells C1 and C2 arranged in the first direction (x), each of the plurality of first conductive wires 210 connected to the first solar cell C1 and the second Each of the plurality of second conductive wires 220 connected to the solar cell C2 may overlap and be connected to each other.

To this end, the ends of the plurality of first conductive wires 210 connected to the first solar cell C1 and the ends of the plurality of second conductive wires 220 connected to the second solar cell C2 are Each of the first and second solar cells C1 and C2 may protrude outside the projection area of the semiconductor substrate 110 and may protrude in a direction facing each other.

In addition, as shown in FIG. 7, the ends of the plurality of first conductive wires 210 connected to the first solar cell C1 and the plurality of second conductive wires connected to the second solar cell C2 ( The wire connection portions where the ends of the wires 220) overlap each other may be connected to each other using the second conductive adhesive 350.

For reference, although numbers are not assigned separately in FIG. 7, the wiring connection portion includes each of the first conductive wires 210 connected to the first solar cell C1 and the second conductive wire connected to the second solar cell C2. Each of the fields 220 refers to a part that overlaps and is connected to each other.

In addition, in Figure 7, when the first conductive wire of the first solar cell (C1) and the second conductive wire 220 of the second solar cell (C2) are connected to each other by the second conductive adhesive 350 at the wire connection portion. Although shown as an example, the first conductive wiring of the first solar cell C1 and the second conductive wiring 220 of the second solar cell C2 are directly connected to each other without using the second conductive adhesive 350. It is also possible to become

Here, the second conductive adhesive 350 may be formed of a metal material containing tin (Sn) or an alloy containing tin (Sn).

More specifically, the second conductive adhesive 350 is (1) formed in the form of a solder paste containing tin (Sn) or an alloy containing tin (Sn), or (2) tin in epoxy ( It may be formed in the form of an epoxy solder paste or conductive paste containing an alloy containing Sn) or tin (Sn).

The melting point of the second conductive adhesive 350 may be different from the melting point of the first conductive adhesive 251.

In this way, the melting point of the second conductive adhesive 350 is different from the melting point of the first conductive adhesive 251 for the convenience of the process.

That is, the plurality of first and second conductive wires 210 and 220 are fixed to the rear of the first and second solar cells C1 and C2, but are not completely electrically connected to the first solar cell C1. Each of the plurality of first conductive wires 210 fixed to each other and each of the plurality of second conductive wires 220 fixed to the second solar cell C2 may first be connected by using the second conductive adhesive 350 .

Thereafter, in the heat treatment process during the lamination process, a plurality of first and second conductive wires 210 and 220 are formed on the rear surfaces of each of the first and second solar cells C1 and C2 by the first conductive adhesive 251. , can be electrically connected to each of the two electrodes 141 and 142.

At this time, in order to ensure the electrical and physical stability of the wiring connection portion where the first and second conductive wires 210 and 220 are overlapped and connected by the second conductive adhesive 350, a heat treatment process for the second conductive adhesive 350 is performed. The temperature may be higher than the heat treatment temperature of the lamination process for connecting the first and second conductive wires 210 and 220 to the rear surfaces of the first and second solar cells C1 and C2, respectively.

Accordingly, the second conductive adhesive 350 does not melt during the lamination process, and the first and second conductive wires 210 and 220 can remain connected.

To this end, the second conductive adhesive 350 may include a material having a higher melting temperature than that of the first conductive adhesive 251.

For example, the melting point of the second conductive adhesive 350 may be higher than the melting point of the first conductive adhesive 251 and may be 200°C or lower.

As a more specific example, assuming that the heat treatment temperature of a typical lamination process is 165°C, the melting point of the first conductive adhesive 251 may be between 110°C and 165°C, and the melting point of the second conductive adhesive 350 may be between 110°C and 165°C. It may be greater than 165℃ and less than 200℃.

In addition, in FIG. 7, each of the plurality of first conductive wires 210 fixed to the first solar cell C1 and the plurality of second conductive wires 220 fixed to the second solar cell C2 are connected to each other. The case where the wiring connection portion is connected by the second conductive adhesive 350 has been described as an example.

However, differently from this, in the wiring connection portion, each of the plurality of first conductive wires 210 fixed to the first solar cell C1 and each of the plurality of second conductive wires 220 fixed to the second solar cell C2 are connected to each other. In an overlapping state, they may be physically connected by directly contacting each other by laser heat treatment at 1000°C or higher.

In this case, a groove generated in a laser heat treatment process may be formed on the surface of any one of the first and second conductive wires 210 and 220.

In this way, the structure in which the first conductive wiring 210 fixed to the first solar cell C1 and the second conductive wiring 220 fixed to the second solar cell C2 are overlapped and connected to each other is described in more detail. Looking at it, it is as follows.

Figure 8 is a diagram for explaining in more detail the structure of the wire connection part in the present invention, Figure 8 (a) is a shape of the wire connection part viewed from the plane, and Figure 8 (b) is a shape of the wire connection part seen in cross section. am.

As shown in FIG. 8, when the solar cell module is viewed from the top, each of the plurality of first conductive wires 210 connected to the first solar cell C1 among the plurality of solar cells is connected to the first solar cell C1. may be connected to each other by overlapping with the plurality of second conductive wires 220 connected to the second solar cell C2 immediately adjacent thereto.

Accordingly, a plurality of wiring connection portions may be formed between the first and second solar cells C1 and C2, spaced apart in the second direction (y). That is, the wiring connection unit is connected so that each of the first conductive wires 210 connected to the first solar cell C1 and each of the second conductive wires 220 connected to the second solar cell C2 overlap each other. A number of solar cells can be formed between the first and second solar cells C1 and C2.

Additionally, as shown in FIG. 8, the wiring connection portion may be located between the semiconductor substrate 110 of the first solar cell C1 and the semiconductor substrate 110 of the second solar cell C2.

That is, the wiring connection portion is located between the projection areas of each semiconductor substrate 110 of the first and second solar cells C1 and C2, and is connected to each semiconductor substrate 110 of the first and second solar cells C1 and C2. may be separated.

In this structure, when the wiring connection portion is heat treated and connected with the second conductive adhesive 350 as shown in (b) of FIG. 8, each semiconductor substrate 110 of the first and second solar cells C1 and C2 ) can minimize the degree of heat damage caused by this heat treatment process.

In addition, with this structure, even if a connection defect is found between some solar cells and conductive wiring during the module manufacturing process, the solar cells can be replaced more easily.

In addition, as shown in (b) of FIG. 8, when the solar cell module is viewed in cross section, any one of the plurality of first conductive wires 210 or the plurality of second conductive wires 220 is connected to the other conductive wires. It can be connected to the rear of one conductive wire.

That is, in Figure 8 (b), the front of the second conductive wire 220 connected to the back of the second solar cell C2 is the first conductive wire 210 connected to the back of the first solar cell C1. An example of a case where the connection is overlapped with the rear surface is shown, but contrary to what is shown in (b) of FIG. 8, the front surface of the first conductive wiring 210 connected to the first solar cell C1 is connected to the second solar cell C1. It may also be connected to the back of the second conductive wiring 220 connected to (C2).

In this way, the connection width W350 in the first direction (x) where the first and second conductive wires 210 and 220 are overlapped and connected at the wire connection portion is the physical distance between the first and second conductive wires 210 and 220. In order to sufficiently ensure connection strength and connection resistance, the line width (W200) of each of the first and second conductive wirings 210 and 220 is larger, and the semiconductor substrate 110 of the first solar cell C1 and the second solar cell ( It may be smaller than the spacing between the semiconductor substrates 110 of C2).

In addition, as shown in (b) of FIG. 8, the sum (T250) of the thicknesses of the first and second conductive wires 210 and 220 connected to each other at the wire connection portion is the thickness of the first and second conductive wires 210 and 220. may be greater than the thickness T210 and T220 of the portion overlapping the projection surface of the semiconductor substrate 110 of the first and second solar cells C1 and C2.

In addition, in the wiring connection part of the present invention, in order to alleviate the thermal expansion stress of the first and second conductive wires 210 and 220 connected to each other through a heat treatment process, the first and second conductive wires 210 and 220 are stressed. A further reduction unit may be provided. This is explained in more detail as follows.

FIG. 9 is a diagram for explaining a first modified example in which the first and second conductive wires 210 and 220 between the first and second solar cells in the solar cell module shown in FIG. 8 are provided with stress reduction units.

As shown in FIG. 9, the first and second conductive wires 210 and 220 are connected between the semiconductor substrates 110 and the wire connection portions of the first and second solar cells C1 and C2, respectively, in the thickness direction of the solar cell module. It can be provided with a curved stress reduction part (P210, P220).

That is, as shown in FIG. 9, the first conductive wiring 210 between the wiring connection portion and the semiconductor substrate 110 of the first solar cell C1 is stressed bent in the third direction, which is the thickness direction of the solar cell module. It has a reduction portion (P210), and the second conductive wiring 220 is bent in the third direction (z), which is the thickness direction of the solar cell module, between the wiring connection portion and the semiconductor substrate 110 of the second solar cell C2. A true stress reduction unit (P220) may be provided.

The stress reduction portions (P210, P220) of the first and second conductive wires 210 and 220 may be formed by folding the first and second conductive wires 210 and 220, and the first and second conductive wires 210 and 220 may be formed by folding the first and second conductive wires 210 and 220. , 220) may be folded to protrude toward the front of the solar cell module.

In this way, the first and second conductive wires 210 and 220 are provided with the stress reducing portions (P210 and P220), so that when the first and second conductive wires 210 and 220 are heat treated and connected at the wire connection portion, the first , Even if the second conductive wires 210 and 220 are thermally expanded in the first longitudinal direction (x), the semiconductor substrate 110 ) It is possible to minimize the thermal expansion stress of the first and second conductive wires 210 and 220 fixed to the rear side.

In Figure 9, the case where the stress reduction parts (P210, P220) of each of the first and second conductive wires (210, 220) are provided only between the semiconductor substrate 110 and the wire connection part has been described as an example. However, differently from this, the first, 2 Stress reduction parts (P210, P220) of each of the conductive wires (210, 220) may also be provided in the wire connection part.

This is explained in more detail as follows.

FIG. 10 is a diagram for explaining a second modified example in which the first and second conductive wires 210 and 220 between the first and second solar cells in the solar cell module shown in FIG. 8 are provided with a stress reduction unit.

As shown in FIG. 10, the stress reduction portions (P210, P220) of the first and second conductive wires (210, 220) are located between the semiconductor substrates (110) of the first and second solar cells (C1, C2). However, stress reduction parts (P210, P220) curved in the thickness direction (z) of the module may also be provided at the wiring connection part.

Accordingly, in the present invention, the stress reduction portions (P210, P220) of the first and second conductive wires (210, 220) are formed between the semiconductor substrates (110) of the first and second solar cells (C1, C2). , by being provided at the wiring connection portion, the thermal expansion stress reduction effect of the first and second conductive wirings 210 and 220 is further improved, and the physical adhesion characteristics of the first and second conductive wirings 210 and 220 at the wiring connection portion are further improved. You can do it.

In addition, in FIGS. 9 and 10, the stress reduction portions (P210, P220) of the first and second conductive wires (210, 220) are provided between the semiconductor substrates (110) of the first and second solar cells (C1, C2). However, although the case where it is formed in the thickness direction of the solar cell module was described as an example, the stress reduction portions (P210, P220) of the first and second conductive wires (210, 220) are formed in the second direction rather than the thickness direction of the module. It is also possible.

To be more specific, it is as follows.

FIG. 11 is a diagram for explaining a third modified example in which the first and second conductive wires 210 and 220 between the first and second solar cells in the solar cell module shown in FIG. 8 are provided with a stress reduction unit.

As shown in FIG. 11, the first and second conductive wires 210 and 220 are formed between the first and second solar cells C1 and C2, and are connected to the second solar cells C1 and C2 in the same longitudinal direction as the first and second electrodes 141 and 142. Stress reduction parts (P210, P220) curved in direction (y) may be provided.

In this way, even when the first and second conductive wires 210 and 220 are provided with stress reduction portions (P210 and P220) curved in the second direction (y), as explained in FIGS. 9 and 10, the first , While reducing the thermal expansion stress of the second conductive wires 210 and 220, the physical adhesion characteristics of the first and second conductive wires 210 and 220 at the wire connection portion can be further improved.

9 to 11, the stress reduction units (P210, P220) are aligned in a second direction (y) that intersects the first direction (x), which is the longitudinal direction of the first and second conductive wires 210 and 220, or in the module. The curved shape in the thickness direction (z) was explained as an example.

However, differently from this, the stress reduction units (P210, P220) have slits in portions of the first and second conductive wires (210, 220) located between the semiconductor substrates (110) of the first and second solar cells (C1, C2). It may also be provided in this formed form.

Hereinafter, a method of manufacturing the solar cell module as described above will be described.

Figure 12 is a flow chart for explaining an example of a method for manufacturing a solar cell module according to the present invention.

As shown in FIG. 12, in order to manufacture a solar cell module according to the present invention, first, a plurality of first and second solar cells with first and second electrodes 141 and 142 formed on the back of the semiconductor substrate 110. (C1, C2) can be prepared (S1).

At this time, an example of a solar cell in which the first and second electrodes 141 and 142 are formed on the back of the semiconductor substrate 110 may be as shown in FIGS. 4 to 6.

Thereafter, the insulating layer 252 and the first conductive adhesive 251 may be applied and dried (S2) on the first and second electrodes 141 and 142.

Here, the pattern in which the insulating layer 252 and the first conductive adhesive 251 are applied may be as shown in FIG. 4. Specifically, the first conductive adhesive 251 is connected to the first conductive wiring 210. It can be applied and dried on the first electrode 141 to be connected to the second conductive wiring 220 and the second electrode 142 to be connected to the second conductive wiring 220, and the insulating layer 252 is a first electrode to be insulated from the second conductive wiring 220. It may be applied and dried on the first electrode 141 and on the second electrode 142 to be insulated from the first conductive wiring 210.

Here, the pattern in which the insulating layer 252 and the first conductive adhesive 251 are applied may be the same in the first and second solar cells C1 and C2.

Thereafter, the first and second conductive wires 210 and 220 may be placed on the first and second electrodes 141 and 142 of the first and second solar cells C1 and C2 and then fixed (S3).

Here, there may be various methods for fixing the first and second conductive wires 210 and 220. For example, a long fixing tape is attached to the back of the semiconductor substrate 110 in a direction crossing the longitudinal direction of the first and second conductive wires 210 and 220, so that the first and second conductive wires 210 and 220 are moved. It may be fixed to the back of the semiconductor substrate 110 to prevent this, and as another example, the first conductive adhesive 251 may be heat treated to temporarily bond it.

Thereafter, the first and second solar cells C1 and C2 are arranged to be spaced apart in the first direction (x), and the second solar cell C2 can be rotated (S4).

That is, the first and second solar cells C1 and C2 are arranged to be spaced apart in the first direction (x), and the first conductive wiring 210 and the second solar cell C2 are fixed to the first solar cell C1. ), the second solar cell (C2) can be rotated 180° and placed adjacent to the first solar cell (C1) so that the second conductive wires 220 fixed to each other are positioned in a straight line.

Thereafter, the first conductive wiring 210 of the first solar cell C1 and the second conductive wiring 220 of the second solar cell C2 may be connected to each other (S5) through a heat treatment process.

At this time, as shown in FIGS. 7 to 11, the first conductive wiring 210 of the first solar cell C1 and the second conductive wiring 220 of the second solar cell C2 are made of a second conductive adhesive ( 350) can be connected to each other.

In addition, here, the temperature of the heat treatment process is higher than the temperature of the lamination process, which will be described later, and may be 200°C or less.

For example, if the maximum temperature of the lamination process is 165°C, the heat treatment process temperature in step S5 may be between 165°C and 200°C.

Accordingly, as the second conductive adhesive 350, a solder paste with a melting point higher than the temperature of the lamination process and 200°C or lower or a conductive adhesive paste containing metal particles in the resin may be used.

Thereafter, the first and second conductive wires 210 and 220 fixed to the first and second solar cells C1 and C2 are connected to the first and second electrodes 141 of the first and second solar cells C1 and C2 through a lamination process. , 142) can be electrically connected to each (S6).

Accordingly, a solar cell module as described in FIGS. 1 to 7 can be formed.

The maximum temperature of this lamination process may be between 160°C and 170°C, and more preferably 165°C. However, it is not necessarily limited to this.

In this lamination process, the first conductive adhesive 251 may be softened and then reconnected, and the insulating layer 252 may not be melted.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims are also possible. falls within the scope of rights.

Claims (14)

In the solar cell module,
A semiconductor substrate, a plurality of solar cells each having a first electrode and a second electrode on a rear surface of the semiconductor substrate and arranged to be spaced apart in a first direction; and
It includes a plurality of first conductive wires connected to the rear surface of the first electrode and a plurality of second conductive wires connected to the rear surface of the second electrode,
Each of the plurality of first conductive wires connected to a first solar cell among the plurality of solar cells overlaps each of the plurality of second conductive wires connected to the second solar cell immediately adjacent to the first solar cell by a conductive adhesive, connected,
Each of the first and second electrodes is disposed long in a second direction intersecting the first direction,
Each of the first and second conductive wires is disposed long in a first direction crossing the first and second electrodes on the rear surface of the semiconductor substrate,
Each of the first and second conductive wires is provided with a stress reduction unit that reduces thermal expansion stress of each of the first and second conductive wires between the semiconductor substrates of the first and second solar cells,
The stress reduction unit has a shape in which each of the first and second conductive wires is curved in the second direction on the plane of the solar cell module, or has a shape curved in the thickness direction of the solar cell module,
The first conductive wiring is connected to the first electrode by a first conductive adhesive at a portion where it intersects the first electrode, and is insulated from the second electrode by an insulating layer at a portion where it intersects the second electrode,
The second conductive wiring is connected to the second electrode by the first conductive adhesive at a portion where it intersects the second electrode, and is insulated from the first electrode by the insulating layer that intersects the first electrode,
The first conductive wires and the second conductive wires are connected to each other by a second conductive adhesive,
The first and second conductive wires are fixed to the first and second solar cells, but are not completely electrically connected to each of the plurality of first conductive wires fixed to the first solar cell and the second solar cell. Each of the plurality of second conductive wires is first connected by the second conductive adhesive,
Thereafter, in the heat treatment process during the lamination process, each of the plurality of first and second conductive wires is electrically connected to each of the first and second electrodes formed on the back of each of the first and second solar cells by the first conductive adhesive. ,
The melting point of the second conductive adhesive is higher than the melting point of the first conductive adhesive solar cell module. According to claim 1,
A wiring connection portion in which each of the first conductive wires connected to the first solar cell and each of the second conductive wires connected to the second solar cell overlaps and connects the semiconductor substrate of the first solar cell and the second conductive wire. A solar cell module located between the semiconductor substrates of the solar cell. According to clause 2,
In the wiring connection portion, one of the first conductive wires or the second conductive wires is connected to a rear surface of the other conductive wires. According to clause 2,
The width in the first direction where the first and second conductive wires overlap in the wire connection portion is greater than the line width of each of the first and second conductive wires, and the semiconductor substrate of the first solar cell and the second solar cell A solar cell module that is smaller than the spacing between semiconductor substrates. According to clause 2,
A solar cell module in which the sum of the thicknesses of the first and second conductive wires connected to each other at the wire connection portion is greater than the thickness of a portion of the first and second conductive wires that overlaps the projection surface of the semiconductor substrate of the first and second solar cells. . delete delete According to clause 2,
A solar cell module in which each of the first conductive wires connected to the first solar cell and each of the second conductive wires connected to the second solar cell are located on the same line. delete According to claim 1,
A solar cell module wherein the second conductive adhesive has a melting point of 200°C or lower. According to clause 2,
A solar cell module in which the first conductive wires and the second conductive wires are connected by physically contacting each other in an overlapping state in the wire connection portion. delete delete According to claim 1,
A solar cell module wherein the first direction length of each of the first and second conductive wires is longer than the first direction length of the semiconductor substrate and is smaller than the sum of the first direction length of the semiconductor substrate and the spacing between the solar cells.

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