KR20170013053A

KR20170013053A - Solar cell module

Info

Publication number: KR20170013053A
Application number: KR1020150105902A
Authority: KR
Inventors: 심승환; 정일형
Original assignee: 엘지전자 주식회사
Priority date: 2015-07-27
Filing date: 2015-07-27
Publication date: 2017-02-06

Abstract

The present invention relates to a solar cell module. The solar cell module includes: a plurality of solar cells arranged in at least two inner strings positioned between first and second outer strings, wherein the first and second outer string are spaced apart from each other in a first direction within a frame; an inter-connector electrically connecting the first and second external strings and the plurality of solar cells arranged in the at least two inner strings in a second direction; and a terminal box located within the frame and having at least three bypass diodes electrically connected to the inter-connector, wherein at least one of the plurality of solar cells includes at least two auxiliary electrodes connected to the terminal box in the second direction by at least two inter-connectors spaced apart from each other in the first direction.

Description

Solar cell module {SOLAR CELL MODULE}

The present invention relates to a solar cell module.

Recently, as energy resources such as petroleum and coal are expected to be depleted, interest in alternative energy to replace them is increasing, and solar cells that produce electric energy from solar energy are attracting attention. The solar power generation system is formed by connecting a plurality of solar cell modules in series or in parallel, and each solar cell module has a plurality of solar cells arranged in a plurality of strings. Here, the string is formed by connecting a plurality of solar cells arranged in a line in series.

Each of the solar cell modules is provided with a branching device, for example, a junction box for drawing electric power generated from a plurality of solar cells to an external system, and is connected in series or in parallel with a neighboring solar cell module by a cable connected to the terminal box .

SUMMARY OF THE INVENTION It is an object of the present invention to improve the efficiency of a solar cell module.

A solar cell module according to an example of the present invention includes a first outer string and a second outer string spaced apart in a first direction in a frame and a plurality of second outer strings arranged in at least two inner strings positioned between the first and second outer strings Solar cell; An interconnect connector electrically connecting the plurality of solar cells arranged in the at least two internal strings with the first and second external strings in a second direction; And at least three bypass diodes electrically connected to the interconnector, wherein at least one solar cell of the plurality of solar cells is connected to at least two interconnectors spaced in a first direction And at least two auxiliary electrodes connected to the terminal box in the second direction.

Here, the plurality of solar cells may include a semiconductor substrate; A first doping portion disposed on a first surface of the semiconductor substrate and doped with an impurity of a first conductivity type; A second doping portion disposed on a second surface opposite to the first surface of the semiconductor substrate and doped with an impurity of a second conductivity type opposite to the first conductivity type; A first electrode electrically connected to the first doping portion; And a second electrode electrically connected to the second doping.

In this case, the first doping portion includes a first non-doped region in which the impurity of the first conductivity type is not doped, and the second doping portion includes a second non-doped region in which the impurity of the second conductivity type is not doped.

The first electrode is spaced apart from the first auxiliary electrode and the second auxiliary electrode by the first non-doped region, and the second electrode is separated by the second non-doped region to the third auxiliary electrode and the fourth auxiliary electrode.

Further, a first insulating film, a third auxiliary electrode, and a second insulating film located in the second non-doped region are formed between the first auxiliary electrode and the second auxiliary electrode, between the first auxiliary electrode and the fourth auxiliary electrode .

Here, the first and second insulating films are made of a metal material that does not transmit light.

The solar cell according to the embodiment of the present invention can prevent the light from being transmitted through a part of the semiconductor substrate without performing a separate cutting process and divide the electrode into at least two auxiliary electrodes so that the breakage loss Output loss may not occur.

Further, since the undoped region is located between the at least two auxiliary electrodes, the amount of charges lost due to the recombination of electrons and holes in the vicinity of the electrodes can be reduced, and the shunting phenomenon caused by the recombination can be prevented .

The electrodes separated by the at least two auxiliary electrodes are electrically connected to the terminal box having the plurality of bypass diodes through the interconnector, thereby reducing the shading loss.

Thus, the efficiency of the solar cell module can be further increased.

1 and 2 are views schematically showing an example of a solar cell module according to an embodiment of the present invention.
FIGS. 3A and 3B are diagrams showing details of a solar cell included in the solar cell module shown in FIGS. 1 and 2. FIG.
4 is a detailed view illustrating an electrical connection structure of the solar cell module shown in FIG.
5 is a diagram illustrating the connection relationship between the solar cell shown in FIG. 4 and the terminal box in detail.
FIGS. 6A and 6B are diagrams for explaining another embodiment of the isolation electrode structure applied to the solar cell module shown in FIGS. 1 and 2. FIG.
7 is a view for explaining another embodiment of a solar cell applied to the solar cell module of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

In the drawings, the thickness is enlarged to clearly represent the layers and regions. When a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case directly above another portion but also the case where there is another portion in between. Conversely, when a part is "directly over" another part, it means that there is no other part in the middle. Further, when a certain portion is formed as "whole" on another portion, it means not only that it is formed on the entire surface of the other portion but also that it is not formed on the edge portion.

Hereinafter, the front surface may be one surface of the semiconductor substrate to which the direct light is incident, and the rear surface may be the opposite surface of the semiconductor substrate in which direct light is not incident, or reflected light other than direct light may be incident.

In the following description, the meaning of two different components having the same length or width means that they are equal to each other within an error range of 10%.

Hereinafter, a solar cell module according to an embodiment of the present invention will be described with reference to the accompanying drawings.

FIGS. 1 and 2 are views schematically showing an example of a solar cell module according to an embodiment of the present invention. FIGS. 3A and 3B are views showing a solar cell module included in the solar cell module shown in FIGS. Fig.

1 and 2, a solar module 100 according to an embodiment of the present invention includes a plurality of solar cells 10, an interconnector (not shown) for electrically connecting a plurality of solar cells 10 20, a front protective portion 30 and a rear protective portion 40 for protecting the plurality of solar cells 10, a light-transmissive front sheet 50 located on the front surface of the solar cell 10, And a back sheet 60 positioned on the rear side of the sheet.

As shown in FIG. 1, the solar cell 10 is a bifacial solar cell that receives external light through a front surface and a rear surface of a semiconductor substrate, respectively. At this time, the solar cell 10 may be spaced apart from the adjacent solar cell 10 by a width of about 10-50 mu m.

1, the light-transmissive front sheet 50 is disposed on the first surface of the solar cell 10, for example, on the light-receiving surface side of the solar cell 10, and has a high transmittance and is made of tempered glass have. At this time, the tempered glass may be a low iron tempered glass having a low iron content. The light-transmissive front sheet 50 may be embossed or textured to improve the light scattering effect. At this time, the light-transmissive front sheet 50 may have a refractive index of about 1.52.

1, the front surface protecting portion 30 and the rear surface protecting portion 40 are formed to prevent corrosion of the metal due to moisture penetration and to protect the solar cell 10 and the solar cell module 100 from impact It is an encapsulate material.

The front protective portion 30 and the rear protective portion 40 may be made of materials such as ethylene vinyl acetate (EVA), polyvinyl butyral, silicon resin, ester resin, and olefin resin. At this time, the front surface protecting portion 30 and the rear surface protecting portion 40 may be adhered to each other by lamination.

As shown in FIG. 1, the interconnector 20 connected to the plurality of solar cells 10 may be embedded in the front protective portion 30 and the rear protective portion 40. At this time, the side surface of the solar cell 10 may be in contact with both the front surface protection portion 30 and the rear surface protection portion 40. When at least a part of the interconnector 20 or the interconnector 20 and the solar cell 10 is embedded in the front surface protection portion 30, the position of the solar cell 10 is fixed by the front surface protection portion 30, The problem of misalignment in the modularization process of the present invention can be reduced.

As shown in FIG. 1, the backsheet 60 is made of a thin sheet of insulating material such as FP / PE / FP (fluoropolymer / polyeaster / fluoropolymer), but may be an insulating sheet made of another insulating material.

The rear sheet 60 protects the solar cell 10 from the external environment by preventing moisture from penetrating from the rear surface of the solar cell module 100. Such a backsheet 60 may have a multi-layer structure such as a layer preventing moisture and oxygen penetration, a layer preventing chemical corrosion, and a layer having an insulating property.

2, the solar cell module 100 includes a plurality of solar cells 10, an interconnector 20, a front surface protection portion 30, a rear surface protection portion 40, A frame 300 for accommodating the front sheet 50 and the rear sheet 60 and a junction box JB for collecting electric power produced from the plurality of solar cells 10.

A first region A1 in which a plurality of solar cells 10 are located and a second region A2 located in a rim of the first region A1 and a second region A2 in the first region A1 The plurality of solar cells 10 may be arranged in a plurality of strings.

Here, the string refers to a minimum series group in which a plurality of solar cells are arranged in a line and are electrically connected.

As such, the solar cell module 100 may include six strings, i.e., first through sixth strings S1-S6.

The strings S1 and S6 located at the corner of the solar cell module 100 are respectively referred to as a first outer string S1 and a second outer string S6 and the first outer string S1 and the second outer string S6, The strings S2 to S5 positioned between the first internal string S6 and the second internal string S6 may be referred to as a first internal string S2, a second internal string S3, a third internal string S4 and a fourth internal string S5, respectively have. At this time, the first outer string S1 and the second outer string S6 may be spaced apart at regular intervals.

In the first outer string S1, the second outer string S6, the first inner string S2, the second inner string S3, the third inner string S4 and the fourth inner string S5, The plurality of solar cells 10 arranged can be electrically connected by the interconnector 20. [

3A and 3B, a solar cell 10 included in the solar cell module 100 of the present embodiment includes a semiconductor substrate 110, an emitter section 120, a first anti-reflection film 130, A first electrode 140, a back surface field (BSF) 170, a second antireflection film 132, and a plurality of second electrodes 150.

A solar cell 10 according to an embodiment of the present invention is a double-sided light receiving solar cell in which light is incident through a first surface and a second surface of a semiconductor substrate 110, The current can be produced by using incident light.

3A and 3B, the semiconductor substrate 110 includes a first surface (hereinafter referred to as a front surface) and a second surface (hereinafter referred to as a rear surface) And the back surface are opposite to each other.

The first and second antireflection films 130 and 132 and the backside electrical section 170 may be omitted but may be omitted if the first and second antireflection films 130 and 132 and the backside electrical section 170 are provided. Since the efficiency of the battery is further improved, the first and second anti-reflection films 130 and 132 and the rear electric part 170 will be described as embodiments.

The semiconductor substrate 110 may have a first conductivity type, for example, an n-type conductivity type. The semiconductor substrate 110 may be formed of any one of single crystal silicon, polycrystalline silicon, and amorphous silicon. In one example, the semiconductor substrate 110 may be formed of a crystalline silicon wafer.

Impurities of pentavalent elements such as phosphorus (P), arsenic (As), and antimony (Sb) may be doped into the semiconductor substrate 110 when the semiconductor substrate 110 has an n-type conductivity type . Alternatively, however, the semiconductor substrate 110 may be of the p-type conductivity type. When the semiconductor substrate 110 has a p-type conductivity type, an impurity of a trivalent element such as boron (B), gallium, indium, or the like can be doped into the semiconductor substrate 110.

The semiconductor substrate 110 may be textured to form the surface of the semiconductor substrate 110 as a texturing surface. When the surface of the semiconductor substrate 110 is formed as a textured surface, the light reflection on the light receiving surface of the semiconductor substrate 110 is reduced, and the incidence and reflection operations are performed on the textured surface, . Thus, the efficiency of the solar cell is improved.

3A and 3B, the emitter section 120 is formed on the entire surface of the semiconductor substrate 110 of the first conductivity type, and has a second conductivity type opposite to the first conductivity type, for example, a p-type Conductive type impurities may be doped in the semiconductor substrate 110 and may be located inside the front surface of the semiconductor substrate 110. [ Thus, the emitter portion 120 of the second conductivity type forms a p-n junction with the first conductive type portion of the semiconductor substrate 110.

Light incident on the semiconductor substrate 110 is separated into electrons and holes, so that the electrons move toward the n-type and the holes move toward the p-type. Accordingly, when the semiconductor substrate 110 is of the n-type and the emitter section 120 is of the p-type, the separated electrons may move toward the back surface of the semiconductor substrate 110 and the separated holes may move toward the emitter section 120.

Since the emitter section 120 forms a pn junction with the first conductive section of the semiconductor substrate 110, that is, the first conductive section of the semiconductor substrate 110, unlike the present embodiment, the semiconductor substrate 110 has a p- The emitter section 120 may have an n-type conductivity type. In this case, the separated holes move toward the rear surface of the semiconductor substrate 110, and the separated electrons can move toward the emitter section 120.

When the emitter section 120 has a p-type conductivity type, the emitter section 120 may be formed by doping an impurity of a trivalent element into the semiconductor substrate 110. Conversely, when the emitter section 120 has an n-type conductivity type, And may be formed by doping an impurity of the pentavalent element into the semiconductor substrate 110.

Specifically, as shown in FIG. 3B, the emitter section 120 may include a first non-doped region A3 in which an impurity of the second conductivity type is not doped. Here, the width of the first undoped region A3 may be about 100 mu m to 800 mu m.

The first electrode 140 described later by the first non-doped region A3 located in the emitter portion 120 may be physically spaced apart by at least two auxiliary electrodes.

Conventionally, although the electrode is cut by cutting the electrode using a laser, there is a problem that an output loss occurs due to a breakage loss occurring when the laser is cut.

In this embodiment, since the emitter section 120 includes the first non-doped region A3, the amount of charges lost by recombination of electrons and holes in the vicinity of the front electrode is reduced, and the shunting caused by the recombination is reduced. The phenomenon can be prevented.

3A and 3B, the first antireflection film 130 is located on the front surface of the semiconductor substrate 110. When the emitter section 120 is located on the front surface of the semiconductor substrate 110, The barrier layer 130 may be located on the emitter layer 120.

The first antireflection film 130 may be formed of at least one material selected from silicon nitride (SiNx), silicon oxide (SiO2), and titanium dioxide (TiO2). The first antireflection film 130 reduces the reflectivity of light incident on the solar cell 10 and increases the selectivity of a specific wavelength region to increase the efficiency of the solar cell 10.

The first antireflection film 130 may have a thickness of about 70 nm to 80 nm.

In this embodiment, the first antireflection film 130 has a single film structure but may have a multilayer structure such as a bilayer film. By doing so, the passivation function of the first antireflection film 130 can be further enhanced, Can be further improved. On the other hand, the first antireflection film 130 may be omitted if necessary.

The first antireflection film 130 may be formed on the front surface of the semiconductor substrate 110 by using various film forming methods such as a PECVD or a Chemical Vapor Deposition .

3A and 3B, the rear electric section 170 may be located on the rear surface of the semiconductor substrate 110, which is opposite to the front surface of the semiconductor substrate 110. Impurities of the same conductivity type as that of the semiconductor substrate 110 may be formed on the semiconductor substrate 110), for example, a P + region.

A potential barrier is formed due to a difference in impurity concentration between the first conductive region and the back conductive portion 170 of the semiconductor substrate 110, thereby preventing electron movement toward the rear conductive portion 170, On the other hand, it facilitates hole transport toward the rear electric section 170. Therefore, it is possible to reduce the amount of charge lost due to the recombination of electrons and holes at the back surface and the vicinity of the semiconductor substrate 110 and to accelerate the movement of a desired charge (e.g., a hole) .

The backside electrical section 170 may include a non-doped region A4 in which impurities of the first conductivity type are not doped. Here, the width of the second undoped region A4 may be about 100 μm to 800 μm. At this time, the width of the second non-doped region A4 may be equal to the width of the first non-doped region A3, but it is not limited thereto and may be formed differently.

Specifically, as shown in FIG. 3B, the second electrode 150 described later by the second non-doped region A4 located in the rear electric section 170 is physically separated by at least two auxiliary electrodes Can be located.

In this embodiment, since the back electric section 170 includes the second non-doped region A4, it is possible to reduce the amount of electric charges lost due to the recombination of electrons and holes near the rear electrode and to prevent the shunting ) Phenomenon can be prevented.

3A and 3B, the second antireflection film 132 may be positioned on the rear surface opposite to the front surface of the semiconductor substrate 110, and the rear electrical part 170 may be formed on the rear surface of the semiconductor substrate 110 The second antireflection film 132 may be located on the top surface of the rear electric field portion 170. At this time, the second antireflection film 132 may minimize reflection of light incident on the rear surface of the semiconductor substrate 110.

The second antireflection film 132 may be formed of at least one of a silicon nitride film (SiNx), a silicon oxide film (SiO2), and titanium dioxide (TiO2). At this time, the second antireflection film 132 may be formed of the same material as the first antireflection film 130 or may be formed of a different material. The second antireflection film 132 may have the same thickness as the first antireflection film 132, that is, about 70 nm to 80 nm.

The second antireflection film 132 may be formed by the same method as the first antireflection film 130 or may be formed by a different method.

Although not shown, a passivation layer may be further formed between the first antireflection film 130 and the emitter layer 120 or between the second antireflection film 132 and the rear electric field layer 170. The protective film may be made of an amorphous semiconductor. For example, the passivation layer may be made of hydrogenated intrinsic amorphous silicon (i-a-Si: H). The protective film may be formed by replacing a defect such as a dangling bond mainly present on the surface of the substrate 110 and the vicinity thereof with a stable bond using hydrogen (H) contained in the protective film, To reduce the amount of charge lost at and near the surface of the substrate 110 due to the defects. As a result, the amount of charge lost on the surface of the substrate 110 due to the defect by the protective film located on the front and rear surfaces of the substrate 110 and in the vicinity thereof is reduced, thereby increasing the efficiency of the solar cell.

3A and 3B, the plurality of first electrodes 140 are spaced apart from each other on the front surface of the semiconductor substrate 110 except for the first undoped region A3, The first auxiliary electrode 140a and the second auxiliary electrode 140b may be arranged to extend in a longitudinal direction. As described above, the electrode spaced apart from the front surface of the semiconductor substrate 110 and extending in the first direction (x) may be referred to as a front finger.

The first auxiliary electrode 140a and the second auxiliary electrode 140b may be spaced apart from each other by the first non-doped region A3. At this time, the width of the first undoped region A3 may be about 100 μm to 800 μm.

The first auxiliary electrode 140a and the second auxiliary electrode 140b may be electrically and physically connected to the emitter section 120 located on the front surface of the semiconductor substrate 110 through the first anti-reflective layer 130 . That is, the first auxiliary electrode 140a and the second auxiliary electrode 140b may be located on the emitter section 120 in a region where the first anti-reflection film 130 is not located.

Accordingly, the plurality of first electrodes 140 may be formed of a conductive material, and may collect charges (for example, holes) that have migrated toward the emitter section 120. The conductive material may be at least one selected from the group consisting of Ni, Cu, Ag, Al, Sn, Zn, In, Ti, Au, And combinations thereof, but may be made of other conductive materials.

3A and 3B, the plurality of second electrodes 150 are spaced apart from each other on the rear surface of the semiconductor substrate 110 except for the second undoped region A4, And a third auxiliary electrode 150a and a fourth auxiliary electrode 150b which are extended in a longitudinal direction. As described above, the electrodes spaced apart from each other on the rear surface of the semiconductor substrate 110 and extending in the first direction (x) may be referred to as rear fingers.

The third auxiliary electrode 150a and the fourth auxiliary electrode 150b may be spaced apart from each other by the second non-doped region A4. At this time, the width of the second non-doped region A4 may be about 100 μm to 800 μm.

The third auxiliary electrode 150a and the fourth auxiliary electrode 150b may be located at positions facing the first auxiliary electrode 140a and the second auxiliary electrode 140b with the semiconductor substrate 110 as a center. Accordingly, the number of the first electrode 140 and the number of the second electrode 150 may be the same, but the present invention is not limited thereto.

The third auxiliary electrode 150a and the fourth auxiliary electrode 150b may be electrically and physically connected to the rear electric part 170 located on the rear surface of the semiconductor substrate 110 through the second anti- That is, the third auxiliary electrode 150a and the fourth auxiliary electrode 150b may be located in the rear electric portion 170 of the region where the second anti-reflection film 132 is not located.

Accordingly, the plurality of second electrodes 150 may be formed of a conductive material, and may collect electric charges, for example, charges moving from the rear electric section 170 side. The conductive material may be at least one selected from the group consisting of Ni, Cu, Ag, Al, Sn, Zn, In, Ti, Au, And combinations thereof, but may be made of other conductive materials.

The first electrode 140 is electrically connected to the second electrode 150 by the first auxiliary electrode 140a and the second auxiliary electrode 140b by the first and second non-doped regions A3 and A3. The third auxiliary electrode 150a and the fourth auxiliary electrode 150b do not generate an output loss due to a breakage loss occurring when the electrode is cut using the laser.

However, in the case of cutting the electrode using a laser, after the process of minimizing the defect of the cut surface of the solar cell is performed, when the interconnector is connected to the separated electrode in the tabbing process for connecting the solar cells in series, ) May not be sophisticated.

Further, by performing the process of minimizing defects on the cut surface of the solar cell, the size of the solar cell is reduced, and the separation distance is increased, so that the length of the interconnector is increased and the manufacturing cost is increased.

Accordingly, in this embodiment, the emitter layer 120 includes the first non-doped region A3 and the rear electric field portion 170 includes the second non-doped region A4, The separation process of the two electrodes 150 may be further simplified to reduce the manufacturing cost and the manufacturing time, thereby increasing the efficiency of the solar cell module.

On the other hand, in the case of the double-sided light receiving type solar cell, the amount of light incident through the front surface of the semiconductor substrate 110 is larger than the amount of light incident through the rear surface, The second electrode 150 may be formed. In this case, the interval between the second electrodes 150, that is, the pitch may be smaller than the interval between the first electrodes 140.

Hereinafter, the electrical connection structure of the solar cell module will be described in detail.

FIG. 4 is a view illustrating an electrical connection structure of the solar cell module shown in FIG. 2 in detail, and FIG. 5 is a diagram illustrating a connection relationship between the solar cell and the terminal box shown in FIG.

4, a plurality of solar cells 10 arranged in the first outer string S1 are connected in a second direction y by a first inter connecter 210 and a second inter connecter 212 .

Specifically, the first auxiliary electrode 140a of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacently to the first external string S1 in the second direction y The third auxiliary electrode 150a of the second electrode 150 of the solar cell adjacent to the one solar cell is connected to the first inter connecter 210 of the first external string S1 and the first external string S1 The second auxiliary electrode 140b of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacently to each other in the second direction y on the other side of the solar cell 10, The fourth auxiliary electrode 150b of the second electrode 150 and the second inter connecter 212 of the first external string S1 may be connected.

4, a plurality of solar cells 10 arranged in the first internal string S2 are connected in a second direction y by a first inter connecter 220 and a second inter connecter 222 .

Specifically, the first auxiliary electrode 140a of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacent to each other in the second direction y in the first internal string S2 The third auxiliary electrode 150a of the second electrode 150 of the solar cell adjacent to the one solar cell is connected to the first inter connecter 220 of the first internal string S2 and the first internal string S2 The second auxiliary electrode 140b of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacently to each other in the second direction y on the other side of the solar cell 10, The fourth auxiliary electrode 150b of the second electrode 150 may be connected to the second inter connecter 222 of the first inner string S2.

4, a plurality of solar cells 10 disposed in the second internal string S3 are connected in a second direction y by a first inter connecter 230 and a second inter connecter 232 .

Specifically, the first auxiliary electrode 140a of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacent to each other in the second direction y in the second internal string S3 The third auxiliary electrode 150a of the second electrode 150 of the solar cell adjacent to the one solar cell is connected to the first inter connector 230 of the second internal string S3 and the second internal string S3 The second auxiliary electrode 140b of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacently to each other in the second direction y on the other side of the solar cell 10, The fourth auxiliary electrode 150b of the second electrode 150 and the second inter connecter 232 of the second inner string S3 may be connected.

4, the plurality of solar cells 10 arranged in the third internal string S4 are connected in the second direction y by the first inter connecter 240 and the second inter connecter 242 .

Specifically, the first auxiliary electrode 140a of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacent to each other in the second direction y in the third internal string S4 The third auxiliary electrode 150a of the second electrode 150 of the solar cell adjacent to the one solar cell is connected to the first inter connecter 240 of the third internal string S4 and the third internal string S4 The second auxiliary electrode 140b of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacently to each other in the second direction y on the other side of the solar cell 10, The fourth auxiliary electrode 150b of the second electrode 150 and the second inter connecter 242 of the third internal string S4 may be connected.

4, the plurality of solar cells 10 arranged in the fourth internal string S5 are connected in the second direction y by the first inter connecter 250 and the second inter connecter 252 .

Specifically, the first auxiliary electrode 140a of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacent to each other in the second direction y in the fourth internal string S5, The third auxiliary electrode 150a of the second electrode 150 of the solar cell adjacent to the one solar cell is connected to the first inter connecter 250 of the fourth internal string S5 and the fourth internal string S5 The second auxiliary electrode 140b of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacently to each other in the second direction y on the other side of the solar cell 10, And may be connected by the fourth auxiliary electrode 150b of the second electrode 150 and the second inter connecter 252 of the fourth inner string S5.

4, a plurality of solar cells 10 arranged in the second outer string S6 are connected in a second direction y by a first inter connecter 260 and a second inter connecter 262 .

Specifically, the first auxiliary electrode 140a of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacent to each other in the second direction y in the second external string S6 The third auxiliary electrode 150a of the second electrode 150 of the solar cell adjacent to one solar cell is connected to the first inter connecter 260 of the second external string S6 and the second external string S6 The second auxiliary electrode 140b of the first electrode 140 of any one of the plurality of solar cells 10 arranged adjacently to each other in the second direction y on the other side of the solar cell 10, The fourth auxiliary electrode 150b of the second electrode 150 and the second inter connecter 262 of the second external string S6.

As shown in FIG. 5, the first and second interconnectors 210, 212, 220, 222, 230, 232, 240, 240 connecting the plurality of solar cells 10 arranged in the respective strings S1- 242, 250, 252, 260, 262 may be connected to the terminal box JB by first to seventh lead wires LW1, LW2, LW3, LW4, LW5, LW6, LW7.

The first inter connecter 210 of the first outer string S1 is connected to the terminal box JB by the first lead wire LW1 and the second inter connecter 212 of the first outer string S1 is connected to the terminal box JB by the first lead wire LW1, The first inter connecter 220 of the first inner string S2 and the first inter connecter 220 of the first inner string S2 are connected to the terminal box JB by the second lead wire LW2, The first inter connecter 230 of the inner string S3 is connected to the terminal box JB by the third lead wire LW3 and the second inter connecter 232 of the second inner string S3 is connected to the third inter- The first inter connecter 240 of the string S4 is connected to the terminal box JB by the fourth lead wire LW4 and the second inter connecter 242 of the third inner string S4 and the fourth inter- S5 are connected to the terminal box JB by the fifth lead wire LW5 and connected to the second inter connecter 252 and the second outer string S6 of the fourth inner string S5, The first inter connecter 260 of the second connector L56 is connected to the terminal box JB and the second inter connecter 262 of the second external string S6 may be connected to the terminal box JB by a seventh lead LW7.

Here, the terminal box JB may include first through sixth bypass diodes BD1, BD2, BD3, BD4, BD5, and BD6.

The first bypass diode BD1 is connected to the first lead line LW1 by the second lead wire LW2 and the second bypass diode BD2 is connected to the second lead wire LW2 and the third lead wire LW3 The third bypass diode BD3 is connected by the third lead wire LW3 and the fourth lead wire LW4 and the fourth bypass diode BD4 is connected by the fourth lead wire LW4 and the fifth lead wire LW4, The fifth bypass diode BD5 is connected by the fifth lead wire LW5 and the sixth lead wire LW6 and the sixth bypass diode BD6 is connected by the sixth lead wire LW6, And the seventh lead wire LW7.

As described above, since a maximum of six bypass diodes are provided in comparison with a conventional terminal box having a maximum of three bypass diodes, the heat dissipation effect is excellent and the reliability of the solar cell module can be secured.

In addition, by providing up to six bypass diodes in one terminal box, the shading loss can be reduced and the efficiency of the solar cell module can be further increased.

FIGS. 6A and 6B are diagrams for explaining another embodiment of the isolation electrode structure applied to the solar cell module shown in FIGS. 1 and 2. FIG.

6A and 6B, another example of the isolation electrode structure applicable to the solar cell according to the present invention shown in FIGS. 3A and 3B will be described.

In FIGS. 6A and 6B, detailed description of the contents overlapping with those shown in FIG. 3A and FIG. 3B will be omitted and different points will be mainly described.

Therefore, the constituent elements that perform the same functions as those of the solar cell shown in Figs. 6A and 6B are denoted by the same reference numerals as those in Figs. 3A and 3B, and a detailed description thereof will be omitted.

6A and 6B, the solar cell 12 includes a first insulating film 180 and a second non-doped region A3 corresponding to the first undoped region A3 and the second non- 2 insulating film 182 as shown in FIG. That is, the first auxiliary electrode 140a and the second auxiliary electrode 140b are separated by the first non-doped region A3, and the third auxiliary electrode 150a and the fourth auxiliary electrode 150b are spaced apart from each other by the second ratio And may be spaced apart by the doped region A4.

The first insulating layer 180 may be formed to be equal to or smaller than the width of the first undoped region A3 and may be equal to or smaller than the height of the first electrode 140. [

The second insulating layer 182 may be formed to be equal to or smaller than the width of the second undoped region A4 and may be equal to or smaller than the height of the second electrode 150.

Here, the first insulating layer 180 and the second insulating layer 182 may be made of a metal material that does not transmit light.

The first insulating layer 180 and the second insulating layer 182 may be formed of a dielectric layer. For example, the first insulating layer 180 and the second insulating layer 182 may be formed of a-SiOx (amorphous silicon oxide), a-SiNx (amorphous silicon nitride), a- (SiN x H), a hydrogenated silicon oxide film (SiO x), a hydrogenated silicon nitride oxide film (SiN x O y: H), or a hydrogenated silicon nitride oxide film ), A hydrogenated silicon oxynitride film (SiO x N y: H), and a hydrogenated amorphous silicon film (a-Si: H).

A first insulating layer 180 and a second insulating layer 182 made of a metal material that does not transmit light are formed on the front and back surfaces of the semiconductor substrate 110 and the first and second auxiliary electrodes 140a and 140b, 140b and the third auxiliary electrode 150a and the fourth auxiliary electrode 150b to reduce the amount of charges lost due to the recombination of electrons and holes in the vicinity of the electrodes and to prevent shunting caused by recombination, The phenomenon can be prevented.

Accordingly, it is possible to secure a wide surface to be connected to the interconnector, thereby facilitating the connection of the interconnector and simplifying the modularization process of the solar cell.

7, a solar cell having a structure in which the first electrode 140 and the second electrode 150 are disposed on the rear surface of the semiconductor substrate 110 is also applicable.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

100: solar cell module 10: solar cell
20, 210, 212, 220, 222, 230, 232, 240, 242, 250, 252, 260, 262:
140: first electrode 140a: first auxiliary electrode
140b: second auxiliary electrode 150: second electrode
150a: third auxiliary electrode 150b: fourth auxiliary electrode
180, 182: insulating film
S1-S6: first to sixth strings JB: terminal box
BD1-BD6: First to sixth bypass diodes
A1: first region A2: second region
A3: first non-doped region A4: second non-doped region

Claims

A plurality of solar cells arranged in at least two inner strings positioned between the first and second outer strings and the first outer string and the second outer string spaced apart in the first direction within the frame;
An inter connecter electrically connecting the first and second outer strings and the plurality of solar cells arranged in the at least two inner strings in a second direction; And
And a terminal box located within the frame and having at least three bypass diodes electrically connected to the interconnector,
Wherein at least one solar cell of the plurality of solar cells includes at least two auxiliary electrodes connected to the terminal box in the second direction by at least two inter-connectors spaced apart in the first direction.

The method according to claim 1,
The first inter connecter of the first outer string is connected to the terminal box by a first lead wire,
The second inter connecter of the first outer string and the first inter connecter of the first inner string are connected to the terminal box by a second lead,
The first interconnector of the first inner string and the first interconnector of the second inner string are connected to the terminal box by a third lead wire,
A second inter connecter of the second internal string and a first inter connecter of the third internal string are connected to the terminal box by a fourth lead wire,
The first interconnector of the third internal string and the first interconnector of the fourth internal string are connected to the terminal box by a fifth lead wire,
The second inter connecter of the fourth inner string and the first inter connecter of the second outer string are connected to the terminal box by a sixth lead wire,
And the second inter connecter of the second external string is connected to the terminal box by a seventh lead wire.

3. The method of claim 2,
The terminal box includes:
A first bypass diode connected to the first lead line and the second lead line;
A second bypass diode connected by the second lead line and the third lead line;
A third bypass diode connected by the third lead line and the fourth lead line;
A fourth bypass diode connected by the fourth lead line and the fifth lead line;
A fifth bypass diode connected by the fifth lead line and the sixth lead line; And
And a sixth bypass diode connected by the sixth lead line and the seventh lead line.

The method according to claim 1,
Wherein at least one solar cell among the plurality of solar cells is a solar cell,
A semiconductor substrate;
A first doping portion disposed on a first surface of the semiconductor substrate and doped with an impurity of a first conductivity type;
A second doping portion disposed on a second surface opposite to the first surface of the semiconductor substrate and doped with an impurity of a second conductivity type opposite to the first conductivity type;
A first electrode connected to the first doping portion and including first and second auxiliary electrodes spaced apart from each other; And
And a second electrode connected to the second doping portion and including third and fourth auxiliary electrodes spaced apart from each other.

3. The method of claim 2,
Wherein the first inter connecter is connected to a first auxiliary electrode of a first electrode of the first solar cell and a third auxiliary electrode of a second electrode of the second solar cell adjacent to the first solar cell in the second direction,
And the second inter connecter is connected to the second auxiliary electrode of the first electrode of the first solar cell and the fourth auxiliary electrode of the second electrode of the second solar cell.

5. The method of claim 4,
Wherein the first doping portion includes a first non-doped region in which the impurity of the first conductivity type is not doped.

5. The method of claim 4,
And the second doping portion includes a second non-doped region in which the impurity of the second conductivity type is not doped.

The method according to claim 6,
Wherein the first and second auxiliary electrodes are separated by the first undoped region.

8. The method of claim 7,
And the third and fourth auxiliary electrodes are spaced apart by the second undoped region.

9. The method of claim 8,
And a first insulating layer between the first auxiliary electrode and the second auxiliary electrode.

11. The method of claim 10,
Wherein the first insulating layer is located in the first undoped region.

10. The method of claim 9,
And a second insulating film between the third auxiliary electrode and the fourth auxiliary electrode.

13. The method of claim 12,
And the second insulating layer is located in the second undoped region.

A semiconductor substrate;
A first doping portion disposed on a first surface of the semiconductor substrate and doped with an impurity of a first conductivity type;
A second doping portion disposed on a second surface opposite to the first surface of the semiconductor substrate and doped with an impurity of a second conductivity type opposite to the first conductivity type;
A first electrode electrically connected to the first doping portion; And
And a second electrode electrically connected to the second doping,
Wherein the first doping region includes a first undoped region in which an impurity of the first conductivity type is not doped,
And the second doping portion includes a second non-doped region in which the impurity of the second conductivity type is not doped.

15. The method of claim 14,
Wherein the first electrode is spaced apart from the first auxiliary electrode and the second auxiliary electrode by the first undoped region.

15. The method of claim 14,
And the second electrode is spaced apart from the third auxiliary electrode and the fourth auxiliary electrode by the second non-doped region.

16. The method of claim 15,
And a first insulating film between the first auxiliary electrode and the second auxiliary electrode.

18. The method of claim 17,
Wherein the first insulating film is located in the first undoped region.

17. The method of claim 16,
And a second insulating film between the third auxiliary electrode and the fourth auxiliary electrode.

20. The method of claim 19,
And the second insulating film is located in the second undoped region.

21. The method according to claim 18 or 20,
Wherein the first and second insulating films are made of a metal material that does not transmit light.