KR20150086120A - Solar cell module and solar cell - Google Patents

Abstract

The present invention relates to a solar cell and a solar cell module thereof. According to an embodiment of the present invention, the solar cell module includes: a front glass substrate; a rear surface sheet arranged on the rear surface of the front glass substrate; multiple solar cells arranged between the front glass substrate and the rear surface sheet; a first sealing material arranged between the solar cells and the front glass substrate; and a second sealing material arranged between the solar cells and the rear surface sheet. The rear surface sheet includes a core layer made of an insulating material and a stretch inhibitor having a thermal expansion coefficient lower than that of the core layer. According to the present invention, the solar cell includes: a semiconductor substrate; multiple first and second electrodes formed on the rear surface of the semiconductor substrate to be spaced apart from each other; and an insulating member which has first auxiliary electrodes connected to the first electrodes and a second auxiliary electrodes connected to the second electrodes. The insulating member includes a base material layer made of insulating materials and another stretch inhibitor having an expansion coefficient lower than that of the base material layer.

Description

SOLAR CELL MODULE AND SOLAR CELL [0002]

The present invention relates to a solar cell module and a solar cell.

A typical solar cell has a substrate made of different conductivity type semiconductors, such as p-type and n-type, an emitter, and an electrode connected to the substrate and the emitter, respectively. At this time, a p-n junction is formed at the interface between the substrate and the emitter.

Particularly, research and development on a back electrode type solar cell having an n-electrode and a p-electrode formed only on the back surface of a silicon substrate without forming an electrode on the light receiving surface of a silicon substrate for increasing the efficiency of the solar cell is underway. A modularization technique of connecting a plurality of such back electrode type solar cell cells and electrically connecting them is also in progress.

The module and the technique are typical of a method of electrically connecting a plurality of solar cells with a metal interconnection, and a method of electrically connecting a plurality of solar cells with a metal interconnection using a wiring board on which wiring is previously formed.

An object of the present invention is to provide a solar cell module and a solar cell.

An example of a solar cell module according to the present invention includes a front glass substrate; A rear sheet disposed on a rear surface of the front glass substrate; A plurality of solar cells disposed between the front glass substrate and the rear sheet; A first encapsulant disposed between the plurality of solar cells and the front glass substrate; And a second encapsulant disposed between the plurality of solar cells and the back sheet, wherein the back sheet includes a core layer made of an insulating material and a stretch inhibitor having a thermal expansion coefficient lower than that of the core layer.

Here, the contraction inhibitor may be dispersed in the core layer, placed in the core layer in the form of a mesh, or formed as a separate layer in the core layer.

Here, the core layer may include a polymer material, and the expansion / contraction inhibitor may include at least one of carbon nanotubes, boron nitride, ceramics, and glass fibers.

Here, the back sheet may further include a coating layer covering the core layer and performing a moisture-proof function. In this case, the coating layer may include polyvinyl fluoride (PVF), polyvinylidenedifluoride (PVDF) As shown in FIG.

An example of a solar cell according to the present invention includes a semiconductor substrate; A plurality of first electrodes and a plurality of second electrodes formed on the rear surface of the semiconductor substrate and spaced apart from each other; And an insulating member having a first auxiliary electrode connected to the plurality of first electrodes and a second auxiliary electrode connected to the plurality of second electrodes, wherein the insulating member includes a base material layer of an insulating material, And a thermal expansion coefficient lower than the thermal expansion coefficient of the base material layer.

Here, the expansion / contraction inhibitor may be dispersed in the base material layer or arranged in a mesh form in the base material layer.

In addition, the stretch inhibitor may be disposed by forming a separate layer in the base material layer. At this time, the layer forming the expansion / contraction inhibitor may be disposed on the front surface of the base material layer, or a layer forming the expansion / contraction inhibitor may be disposed in the base material layer.

Such an expansion / contraction inhibitor may include at least one of carbon nanotube, boron nitride, ceramics, and glass fibers.

In addition, the base material layer of the insulating member may include at least one material selected from a polymer-based material, an epoxy-based material, and a bismaleimide triazine (BT) resin.

The first auxiliary electrode may include a plurality of first connecting portions connected to the first electrode and a first pad portion having one end connected to an end of the plurality of first connecting portions and the second auxiliary electrode includes a plurality And a second pad portion having one end connected to an end of the plurality of second connecting portions.

At this time, between the first electrode and the first connection portion, and between the second electrode and the second connection portion are electrically connected to each other by the electrode connector, and between the first electrode and the second electrode, and between the first connection portion and the second connection portion An insulating layer may be formed.

The solar cell module according to the present invention can prevent the solar cell from being disturbed during the lamination process by including the stretching inhibitor having a relatively low thermal expansion coefficient on the back sheet.

In addition, the solar cell according to the present invention includes a stretch inhibitor having a relatively low thermal expansion coefficient relative to the insulating member so that when the insulating member is connected to the back surface of the semiconductor substrate, the first and second electrodes, The phosphor can be more easily aligned.

1 is a view for explaining an example of a cross section of a solar cell module according to the present invention.
2 is a view for explaining another example of a back sheet BS according to the present invention.
Figs. 3 to 4C are views for more specifically explaining the constriction agents described in Figs. 1 and 2. Fig.
5 and 6 are views for explaining an example of a solar cell applicable to the solar cell module shown in FIG.
7 is a view for explaining an example of electrode patterns of the semiconductor substrate 110 and the insulating member 200 to be individually connected to each other in the solar cell shown in Figs. 5 and 6. Fig.
8 is a view for explaining a state in which the semiconductor substrate 110 and the insulating member 200 shown in FIG. 7 are connected to each other.
FIG. 9A shows a cross section of the line 7a-7a in FIG.
FIG. 9B is a cross-sectional view taken along line 7B-7B in FIG.
Fig. 9C shows a cross section taken along the line 7c-7c in Fig.
10 shows an example in which the elasticity inhibitor 200R is contained in the insulating member 200. Fig.

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 in the drawings, portions not related to the description are omitted, and like reference numerals are given to similar portions throughout the specification.

Hereinafter, the front surface may be a surface of a semiconductor substrate or a front surface of a front glass substrate to which direct light is incident, and the rear surface may be a surface of a semiconductor substrate on which direct light is not incident, The opposite side of one side of the first side.

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

1 and 2 are views for explaining an example of a solar cell module according to the present invention. Here, FIG. 1 is a view for explaining an example of a sectional view of a solar cell module according to the present invention, and FIG. 2 is a view for explaining another example of a back sheet BS according to the present invention.

1, a solar cell module according to the present invention includes a front glass substrate FG, a first encapsulation material EC1, a plurality of solar cells CE1 and CE2, an interconnector IC, (EC2), and a backsheet (BS). In such a solar cell module, the backsheet BS may comprise a stretch inhibitor (BSR).

As shown in FIG. 1, the front glass substrate FG may be positioned on the front surface of a plurality of solar cells, and may have a high transmittance and may be made of tempered glass or the like to prevent breakage. At this time, the tempered glass may be a low iron tempered glass having a low iron content, and although not shown, the inner side may be subjected to an embossing treatment to enhance the light scattering effect.

The first encapsulation material EC1 may be positioned between the plurality of solar cells CE1 and CE2 and the front glass substrate FG and the second encapsulation material EC2 may be disposed between the plurality of solar cells CE1 and CE2 and the rear surface And may be located between the sheets BS.

The first encapsulation material EC1 and the second encapsulation material EC2 may be formed of a material that protects the solar cell module 100 from impact and prevents corrosion of the metal due to moisture penetration.

The first encapsulation material EC1 and the second encapsulation material EC2 may be made of ethylene vinyl acetate (EVA) or the like.

The first encapsulation material EC1 and the second encapsulation material EC2 are laminated by a lamination process arranged from a front glass substrate to a back sheet BS as shown in FIG. (CE1, CE2).

The plurality of solar cells CE1 and CE2 form a p-n junction, and can generate electricity from light incident from the outside. 1, a semiconductor substrate 110 for forming a pn junction is formed in each of the plurality of solar cells CE1 and CE2, a first auxiliary electrode P141 and a second auxiliary electrode P142 (Not shown) may be provided.

Therefore, each of the plurality of solar cells CE1 and CE2 can be connected to the insulating member 200 and the semiconductor substrate 110 individually, thereby forming one discrete element.

However, the structure of such a solar cell is an example, and the detailed structure of each of the plurality of solar cells CE1 and CE2 can be applied regardless of any kind.

Here, the plurality of solar cells CE1 and CE2 may be connected to each other by an interconnector (IC). For example, the interconnector (IC) may be formed by an interconnecting connector (ICA) And may be connected to the first auxiliary electrode P141 and the second auxiliary electrode P142.

In addition, the rear sheet BS is placed on the rear surface of the second sealing material EC2 in the form of a sheet to prevent moisture from penetrating into the rear surface of the solar cell module.

Such a backsheet BS may include a core layer BSB and a stretch inhibitor BSR, as shown in FIGS.

Here, the core layer (BSB) is not particularly limited as long as it is made of an insulating material. However, the core layer (BSB) may be formed of a polymer material, for example. Here, the polymer materials are polyimide, polyallomer, polyamide (PA), polybutylene (PB), polycarbonate (PC), polyester, polyethylene terephthalate (PET), polypropylene (PSO), polyurethane (PUR), polyvinyl chloride (PVC), and polyvinylidene fluoride (PVDF).

The BSR may be an organic fiber or an inorganic fiber having a thermal expansion coefficient lower than that of the core layer BSB. Specifically, the BSR may be a carbon fiber, a carbon nanotube, a boron nitride, , Ceramic fiber, and glass fiber, and these materials have a relatively low coefficient of thermal expansion to arrange the back sheet (BS) on the second sealing material (EC2), and when performing the lamination process , It is possible to prevent the rear sheet (BS) from being excessively thermally expanded.

More specifically, when the core layer BSB is formed of a polymer-based material (e.g., PET), the thermal expansion coefficient of the core layer BSB may be approximately 60 * 10 -6 / 占 폚. In this case, for example, the thermal expansion coefficient of the stretch inhibitor (BSR) may be lower than about 60 * 10 -6 / 캜.

Although the thermal expansion coefficient of the core layer BSB is 60 * 10 -6 / ° C as an example, the thermal expansion coefficient of the core layer BSB may vary depending on the material, 6 / C. ≪ / RTI >

Such an expansion / contraction inhibitor (BSR) may be dispersed in the core layer (BSB), for example, as shown in Fig. Alternatively, the stretch inhibitor (BSR) may be disposed in the core layer (BSB) in the form of a mesh in the same manner as shown in FIGS. 4A to 4C and formed as a separate layer in the core layer . Specific and various examples of formation of such a stretch inhibitor (BSR) will be described in Figs. 3 to 4C.

In addition, the backsheet (BS) according to the present invention may further include a coating layer (BSC) covering the core layer (BSB) and performing a moisture-proof function, as shown in FIG. That is, the coating layer BSC may be formed entirely on the front and rear surfaces of the core layer BSB.

The material of the coating layer BSC may include, for example, polyvinyl fluoride (PVF) and polyvinylidenedifluoride (PVDF).

By further forming the coating layer BSC on the back sheet BS, it is possible to further prevent moisture from penetrating into the solar cell module.

In addition, the coating layer BSC may further include titanium oxide (TiO2) so as to reflect light incident between the plurality of solar cells CE1 and CE2 and to be incident on the front surface of the solar cell.

As described above, the solar cell module according to the present invention can suppress excessive thermal expansion of the back sheet BS by allowing the back sheet BS to contain the stretching inhibitor (BSR).

Accordingly, when the solar cell module is manufactured, the arrangement of the solar cells can be prevented from being disturbed due to the thermal expansion of the back sheet BS.

Next, Figs. 3 to 4C are views for more specifically describing the contraction inhibitor 200R described in Figs. 1 and 2.

3 (a) shows the arrangement of the stretch inhibitor (BSR) when the back sheet BS according to the present invention is viewed from the plane in a state where the other constitution of the solar cell module is omitted, and Fig. 3 3 (b) is an example of a fiber forming the elastic constriction agent (BSR).

FIG. 4A is an example in which at least one of the fibers forming the BSR according to the present invention is connected to each other, FIG. 4B is an example in which the BSR is formed in the form of a mesh, 4c is an example in which the stretching inhibitor (BSR) is formed as one layer.

As shown in FIG. 3 (a), the stretching inhibitor (BSR) according to the present invention can be variously dispersed in the form of fibers having a length in the base material layer (BSB). Therefore, even when the base material BSB is thermally expanded in the first direction or the second direction when the laminate process is performed by disposing the back sheet BS on the second sealing material EC2, It is possible to suppress excessive thermal expansion of the back sheet BS.

Therefore, it is possible to prevent the arrangement of each solar cell from being disturbed by the excessive thermal expansion of the rear sheet BS.

At this time, the shape of each fiber forming the elastic constriction agent (BSR) may be a ratio of the length (L) to the diameter (R) of 1: 1 to 5,000 as shown in FIG. 3 (b)

Therefore, when the diameter R of the fibers forming the elastic constants BSR is approximately 10 nm, the length L may be between 10 nm and 50 탆.

As shown in FIG. 4A, the stretch inhibitor (BSR) is formed by dispersing and arranging a plurality of fibers forming a stretch inhibitor (BSR) in a base material layer (BSB), wherein at least one of the fibers is formed by being connected to each other There is also water.

In this case, the expansion / contraction inhibitor (BSR) can further suppress the thermal expansion of the base material layer (BSB).

4b, when the backsheet BS is viewed in a plan view, the stretching inhibitor BSR may be arranged in a mesh form in the base material layer BSB, and as shown in Fig. 4b (b) , As shown in FIG. 3B, such a mesh-shaped stretch inhibitor (BSR) may form a separate layer in the base material layer (BSB).

Alternatively, as shown in FIG. 4C, when the rear sheet BS is viewed from a plane, the expansion / contraction inhibitor BSR may be formed by forming a separate layer in the base material layer BSB, The layers may be arranged in a wide plate form. At this time, the expansion / contraction inhibitor BSR disposed in the form of a separate wide plate may be disposed on the front surface of the base material layer BSB as shown in FIG. 4C, As shown, it may be spaced apart from the front surface of the base material layer (BSB) by D.

As described above, the back sheet BS according to the present invention can prevent the arrangement of each solar cell from being disturbed during the lamination process, including the base material layer (BSB) and the stretching inhibitor (BSR) .

FIGS. 5 and 6 are views for explaining an example of a solar cell applicable to the solar cell module shown in FIG. 1, and FIG. 7 is a cross-sectional view of a semiconductor substrate 110 And an electrode pattern of the insulating member 200 according to an embodiment of the present invention.

Here, FIG. 5 is an example of a partial perspective view of a solar cell according to an example of the present invention, and FIG. 6 is a sectional view cut along the line 6-6 of the solar cell shown in FIG.

7A is a view for explaining an example of a pattern of the first electrode C141 and the second electrode C142 disposed on the rear surface of the semiconductor substrate 110 and FIG. 7B is a sectional view taken along line 7B-7B of FIG. 7A. FIG. 7C is a sectional view of the first auxiliary electrode P141 and the second auxiliary electrode P141 disposed on the front surface of the insulating member 200, 7 (d) is a cross-sectional view taken along the line 7 (d) -7 (d) in FIG. 7 (c).

5 and 6, an example of a solar cell according to the present invention includes a semiconductor substrate 110, an antireflection film 130, an emitter section 121, a back surface field (BSF) 172, And includes a plurality of first electrodes C141 and a plurality of second electrodes C142, a first auxiliary electrode P141 and a second auxiliary electrode P142 and an insulating member 200. Here, the antireflection film 130 and the rear electric field portion 172 may be omitted.

The solar cell according to the present invention includes a first auxiliary electrode P141 and a second auxiliary electrode P142 in a state where a plurality of first electrodes C141 and a plurality of second electrodes C142 are formed on a semiconductor substrate 110, The insulating member 200 may be connected to the rear surface of the semiconductor substrate 110, and may be formed as a single integrated element. Hereinafter, the structure of the solar cell according to the present invention will be described, and a specific structure in which the insulating member 200 and the semiconductor substrate 110 are connected to each other will be described.

The semiconductor substrate 110 may be a bulk crystalline semiconductor substrate 110 made of silicon of a first conductivity type, for example, n-type conductive type. The semiconductor substrate 110 may be formed by doping a first conductivity type impurity into a wafer formed of a silicon material.

The emitter portions 121 are spaced apart from each other in the rear surface of the semiconductor substrate 110 facing the front surface, and extend in a direction parallel to each other. The plurality of emitter portions 121 may be a second conductive type which is opposite to the conductive type of the semiconductor substrate 110.

Accordingly, the emitter layer 121 and the semiconductor substrate 110 may form a p-n junction, and the emitter layer 121 may be formed of a p-type conductive type crystalline or amorphous silicon material, for example.

A plurality of rear electric field sections 172 may be disposed in the rear surface of the semiconductor substrate 110 and may be spaced apart from each other in a direction parallel to the plurality of emitter sections 121. In the same direction as the plurality of emitter sections 121, . Therefore, as shown in FIGS. 5 and 6, a plurality of emitter portions 121 and a plurality of rear electric sections 172 are alternately arranged on the rear surface of the semiconductor substrate 110.

The plurality of rear electric fields 172 are impurities, for example, n ++ parts, which contain impurities of the same conductivity type as that of the semiconductor substrate 110 at a higher concentration than the semiconductor substrate 110.

The plurality of first electrodes C141 are physically and electrically connected to the emitter section 121 and extend apart from each other along the emitter section 121. [ The first electrode C141 may extend in the first direction x and the emitter portion 121 may extend in the second direction y when the emitter portion 121 extends in the first direction x. The first electrode C141 may extend in the second direction y.

The plurality of second electrodes C142 are physically and electrically connected to the semiconductor substrate 110 through the rear electric section 172 and extend along the plurality of rear electric sections 172, respectively.

The second electrode C142 may extend in the first direction x and the backside electrical portion 172 may extend in the first direction x when the backside electrical portion 172 extends in the first direction x, y, the second electrode C142 may also extend in the second direction y.

Here, on the rear surface of the semiconductor substrate 110, the first electrode C141 and the second electrode C142 are physically separated from each other and electrically isolated.

As shown in FIG. 7C, the first auxiliary electrode P141 includes a first connecting portion PC141 and a first pad portion PP141. As shown in FIGS. 5 and 6, The first connection part PC141 is connected to the plurality of first electrodes C141 and the first pad part PP141 is connected at one end to the end of the first connection part PC141 as shown in FIG. And the other end can be connected to the inter-connector (IC). The first pad unit PP141 will be described in more detail with reference to FIG.

5 and 6, the first connection unit PC141 may be formed as a plurality of first electrodes C141 and may be connected to the plurality of first electrodes C141, A plurality of first electrodes (C141) may be connected to one barrel electrode.

In addition, when a plurality of first connection parts (PC 141) are formed, the first connection part (PC 141) may be formed in the same direction as the plurality of first electrodes (C 141), or may be formed in an intersecting direction. At this time, the first connection unit (PC 141) may be electrically connected to each other at a portion overlapping with the first electrode (C 141).

The second auxiliary electrode P142 may include a second connection portion PC142 and a second pad portion PP142 as shown in FIG. 7C. 5, the second connection unit PC 142 is connected to the plurality of second electrodes C142, and the second pad unit PP 142 is connected to the second electrodes C142, 2 connection part (PC 142), and the other end can be connected to the inter connector (IC).

5 and 6, the second connection unit PC 142 may be formed as a plurality of second electrodes C142, and may be connected to the plurality of second electrodes C142. Alternatively, as shown in FIG. And a plurality of second electrodes C142 may be connected to one barrel electrode.

Here, when a plurality of second connecting portions PC 142 are formed, the second connecting portions PC 142 may be formed in the same direction as the plurality of second electrodes C 142, or may be formed in an intersecting direction. At this time, the second connection unit (PC 142) may be electrically connected to each other at a portion overlapping the second electrode (C 142).

The first auxiliary electrode P141 and the second auxiliary electrode P142 may be formed of at least one of Cu, Au, Ag, and Al.

The first auxiliary electrode P141 may be electrically connected to the first electrode C141 through an electrically conductive electrode coupling material ECA and the second auxiliary electrode P142 may be electrically connected to the electrode coupling material ECA To the second electrode (C142).

The material of the electrode connection material (ECA) is not particularly limited as long as it is a conductive material. However, a conductive material having a melting point at a relatively low temperature of 130 ° C to 250 ° C is more preferable. For example, Conductive adhesives including metal particles, carbon nanotubes (CNTs), conductive particles including carbon, wires, needles, and the like can be used.

An insulating layer IL for preventing a short circuit may be disposed between the first electrode C141 and the second electrode C142 and between the first auxiliary electrode P141 and the second auxiliary electrode P142 . The insulating layer IL may be an epoxy resin.

5 and 6, the first connection C141 of the first auxiliary electrode P141 and the first connection C141 of the first auxiliary electrode P141 are overlapped with each other, and the second connection of the second electrode C142 and the second auxiliary electrode P142 The first electrode C141 and the second connecting portion PC142 of the second auxiliary electrode P142 may overlap each other and the second electrode C142 may overlap with the second connecting portion PC142. And the first connection unit (PC141) of the first auxiliary electrode (P141) may be overlapped with each other. In this case, between the first electrode C141 and the second connection unit PC 142 of the second auxiliary electrode P142 and between the second electrode C142 and the first connection unit PC141 of the first auxiliary electrode P141 An insulating layer (IL) may be located to prevent shorting.

The first auxiliary electrode P141 and the second auxiliary electrode P142 may be formed by a heat treatment process that applies heat and pressure between 130 ° C and 250 ° C to the electrode connecting material ECA, have.

The insulating member 200 may be disposed on the rear surface of the first auxiliary electrode P141 and the second auxiliary electrode P142.

Such an insulating member 200 may be formed in the form of a flexible film or in the form of a hard plate rather than a flexible one.

In the solar cell according to the present invention, a first auxiliary electrode P141 and a second auxiliary electrode P142 are formed in advance on the entire surface of the insulating member 200, and a plurality of first electrodes The insulating member 200 and the semiconductor substrate 110 may be connected to each other to form a single discrete element in a state in which the plurality of second electrodes C141 and the plurality of second electrodes C142 are formed in advance.

As described above, the solar cell, in which the insulating member 200 and the semiconductor substrate 110 are connected to each other and is formed as one discrete element, can shorten the manufacturing process time, and the first electrode C141 and the second electrode The thermal expansion stress on the substrate can be further reduced, and the efficiency of the solar cell can be further improved, as compared with the case in which the semiconductor layer C142 is directly formed on the rear surface of the semiconductor substrate 110. [

The insulating member 200 may include a first auxiliary electrode P141 and a second auxiliary electrode P142 on the rear surface of the semiconductor substrate 110 in which the first electrode C141 and the second electrode C142 are formed in a semiconductor manufacturing process, The insulating member 200 can more easily assist the aligning process and the bonding process when the front surface of the insulating member 200 formed thereon is attached and connected.

The holes collected through the first auxiliary electrode P141 and the electrons collected through the second auxiliary electrode P142 in the solar cell according to the present invention manufactured by such a structure are electrically connected to the external device through the external circuit device Can be used.

The emitter section 121 is located on the front surface of the semiconductor substrate 110 and the emitter section 121 is formed on the rear surface of the semiconductor substrate 110. [ The present invention can be similarly applied to a solar cell having a structure in which the first electrode C141 formed on the rear surface of the semiconductor substrate 110 is connected to the first electrode C141 through a plurality of via holes.

A solar cell having such a structure can connect solar cells adjacent to each other by an interconnect (IC), and thus a plurality of solar cells can be connected in series.

In this structure, a pattern of the first electrode C141 and the second electrode C142 formed on the rear surface of the semiconductor substrate 110 and a pattern of the first auxiliary electrode P141 And the second auxiliary electrode P142 will be described in more detail as follows.

A front surface of one insulating member 200 as shown in FIGS. 7C and 7D is formed on the back surface of one semiconductor substrate 110 as shown in FIGS. 7A and 7B, By attaching and connecting, the solar cell according to the present invention can form one integrated discrete element. That is, the insulating member 200 and the semiconductor substrate 110 may be bonded or attached at a ratio of 1: 1.

As shown in FIGS. 7A and 7B, a plurality of first electrodes C141 and a plurality of second electrodes C141 are formed on the rear surface of the semiconductor substrate 110 of the solar cell illustrated in FIGS. 5 and 6, (C142) may be spaced apart from each other and elongated in the first direction (x).

Here, as described above, the first auxiliary electrode P141 includes the first connecting portion PC141 and the first pad portion PP141, and the first connecting portion PC141, May be elongated in the first direction x. The first pad portion PP141 may be elongated in the second direction y and may have one end connected to the end of the first connection portion PC141, And can be connected to an inter-connector (IC).

In addition, the second auxiliary electrode P142 also includes a second connecting portion PC142 and a second pad portion PP142. As shown in FIG. 7C, the second connecting portion PC142 includes a first connecting portion The second pad portion PP142 may be formed to be elongated in the second direction y and may have one end connected to the end of the second connection portion PC142, And the other end can be connected to the inter-connector (IC).

Here, the first connection portion PC141 and the second pad portion PP142 may be spaced from each other, and the second connection portion PC142 and the first pad portion PP141 may be spaced apart from each other.

Therefore, on the front surface of the insulating member 200, the first pad portion PP141 may be formed at one end of the both ends of the first direction x and the second pad portion PP142 may be formed at the other end thereof.

As described above, in the solar cell according to the present invention, only one insulating member 200 is coupled to one semiconductor substrate 110 to form one integrated individual element, thereby making it easier to manufacture the solar cell module, Even if the semiconductor substrate 110 included in one of the solar cells is broken or defects are generated during the manufacturing process of the solar cell module, only the corresponding solar cell formed by one integrated type individual element can be replaced and the process yield can be further improved have.

In addition, the solar cell formed by the single integrated device can minimize the thermal stress applied to the semiconductor substrate 110 during the manufacturing process.

On the other hand, the insulating member 200 according to the present invention may include the base material layer 200B and the expansion / contraction inhibitor 200R, similar to the above-described back sheet BS.

The melting point of the insulating member 200 is preferably not less than 300 DEG C, more preferably not more than 300 DEG C, more preferably not more than 300 DEG C, As shown in Fig. More specifically, for example, the material of the base material layer 200B may be formed of at least one material selected from a polymer-based material, an epoxy-based material, and a bismaleimide triazine (BT) resin.

Examples of polymer materials include polyimide, polyallomer, polyamide, polybutylene (PB), polycarbonate (PC), polyester, polyethylene terephthalate (PET), polypropylene (PP) May be at least one of polysulfone (PSO), polyurethane (PUR), polyvinyl chloride (PVC), and polyvinylidene fluoride (PVDF).

The expansion / contraction inhibitor 200R may be formed of organic fibers or inorganic fibers having a thermal expansion coefficient lower than the thermal expansion coefficient of the base material layer 200B. Specific examples thereof include carbon fibers, carbon nanotubes, The insulating material 200 may be formed to include at least one of boron nitride, ceramic fiber and glass fiber. When the insulating material 200 is adhered to the rear surface of the semiconductor substrate 110 due to the relatively low coefficient of thermal expansion, It can serve to suppress the length of thermal expansion of the base material layer 200B.

The thermal expansion coefficient of the expansion and contraction inhibitor 200R is lower than the thermal expansion coefficient of the base material layer 200B and may be higher than the thermal expansion coefficient of the first and second auxiliary electrodes P141 and P142.

Therefore, for example, when the first and second auxiliary electrodes P141 and P142 are formed of copper, the thermal expansion coefficient of the first and second auxiliary electrodes P141 and P142 may be 16.6 * 10-6 / The thermal expansion coefficient of the elastic member 200B is about 60 * 10-6 / 占 폚, for example, the thermal expansion coefficient of the elasticizer 200R is set to be about 16.6 * 10-6 / 占 폚 to 60 * 10-6 / .

However, the thermal expansion coefficient of the elasticity control agent 200R may be lower than that of the first and second auxiliary electrodes P141 and P142, depending on the material. For example, when the expansion / contraction inhibitor 200R is formed of boron nitride, the coefficient of thermal expansion of boron nitride is 1.2 * 10-6 / 占 폚, 1 and 2 auxiliary electrodes P141 and P142.

The insulating member 200 according to the present invention is provided with the expansion and contraction inhibitor 200R capable of suppressing the thermal expansion of the base material layer 200B so that the insulating member 200 is attached to the rear surface of the semiconductor substrate 110 The first and second auxiliary electrodes P141 and P142 of the insulating member 200 are electrically connected to the first and second electrodes C141 and C142 formed on the rear surface of the semiconductor substrate 110 due to the thermal expansion of the base material layer 200B. The first and second electrodes C141 and C142 and the first and second auxiliary electrodes P141 and P142 can be more accurately aligned so that the alignment is minimized.

5 to 7, the stretch inhibitor 200R may be formed in various forms as described in FIGS. 4A to 4C. [0052] In addition, .

Hereinafter, an example in which the insulating member 200 and the semiconductor substrate 110 are separately connected to each other and formed as one discrete element will be described.

FIG. 8 is a view for explaining a state in which the semiconductor substrate 110 and the insulating member 200 shown in FIG. 7 are connected to each other. FIG. 9A is a cross-sectional view taken along line 9a-9a in FIG. FIG. 9C is a cross-sectional view taken along the line 9B-9B in FIG. 8, FIG. 9C is a cross-sectional view taken along the line 9C-9C in FIG. 8, and FIG. 10 is an example in which the contraction inhibitor 200R is contained in the insulating member 200 FIG.

As shown in FIG. 8, one semiconductor substrate 110 may be completely overlapped with one insulating member 200 to form one solar cell individual element.

9A, the first electrode C141 formed on the rear surface of the semiconductor substrate 110 and the first connection portion PC141 formed on the front surface of the insulating member 200 are overlapped with each other, (ECA). ≪ / RTI >

The second electrode C142 formed on the rear surface of the semiconductor substrate 110 and the second connection part PC142 formed on the front surface of the insulating member 200 are overlapped with each other and electrically connected to each other by the electrode connector ECA. have.

The spacing between the first electrode C141 and the second electrode C142 may be filled with an insulating layer IL and the spacing between the first connecting portion PC141 and the second connecting portion PC 142 The insulating layer IL may be filled.

9B, the insulating layer IL may be filled in the spaced space between the second connection portion PC 142 and the first pad portion PP141. As shown in FIG. 9C, The insulating layer IL may be filled in the spaced space between the connection portion PC141 and the second pad portion PP142.

8, each of the first pad portion PP141 and the second pad portion PP142 includes first regions PP141-S1 and PP142-S1 overlapping the semiconductor substrate 110, And a second region PP141-S2, PP142-S2 that do not overlap with the substrate 110. [

As described above, the second region PP141-S2 of the first pad portion PP141 and the second region PP142-S2 of the second pad portion PP142, which are provided for securing a space to be connected to the interconnector IC, (IC) can be connected.

Since the first pad portion PP141 and the second pad portion PP142 according to the present invention include the second regions PP141-S2 and PP142-S2, the interconnector IC can be connected more easily, In addition, thermal expansion stress on the semiconductor substrate 110 can be minimized when the interconnector (IC) is connected.

In addition, as described above, the interconnector (IC) may be connected to the first pad unit PP141 or the second pad unit PP142 to connect a plurality of solar cells.

The first electrode C141 and the second electrode C142 formed on the semiconductor substrate 110 are overlapped in the direction parallel to the first connecting portion PC141 and the second connecting portion PC142 formed on the insulating member 200, The first electrode C141 and the second electrode C142 formed on the semiconductor substrate 110 are electrically connected to the first connection portion PC141 and the second connection portion PC142 formed on the insulating member 200, In the direction intersecting with the direction of the arrows.

In addition, as shown in the drawing, the first connection unit PC141 and the second connection unit PC142 may not be formed in plural, but may be formed as a single tubular electrode, and a plurality of first electrodes C141 and / And the second electrode C142 may be connected.

Although the first pad unit PP141 and the second pad unit PP142 have been described only as one example, the first pad unit PP141 and the second pad unit PP142 may have a plurality of May be formed. A plurality of first connection portions PC141 or a plurality of second connection portions PC142 may be connected to the first pad portion PP141 or the second pad portion PP142 formed in a plurality.

In the solar cell according to the present invention, the insulating member 200 includes the expansion / contraction inhibitor 200R having a thermal expansion coefficient lower than the thermal expansion coefficient of the base material layer 200B, so that, as shown in Figs. 8 to 9C, The first and second electrodes C141 and C142 and the first and second auxiliary electrodes P141 and P142 are aligned more precisely when the first and second electrodes 200 and 200 and the semiconductor substrate 110 are connected to each other to form an individual element. .

Here, the shape of the contraction inhibitor 200R included in the insulating member 200 may be the same as that described in Figs. 4A to 4C.

Therefore, as shown in Fig. 10 (a), when the insulating member 200 is seen in a plan view, the elasticizer 200R can be arranged in a wide plate form. At this time, the stretch inhibitor 200R is disposed on the front surface of the base material layer 200B as shown in FIG. 10 (b) and is in direct contact with the first auxiliary electrode P141 and the second auxiliary electrode P142 Or may be disposed in the base material layer 200B by a distance D from the first and second auxiliary electrodes P141 and P142 as shown in FIG. 10 (c).

As described above, the insulating member 200 according to the present invention includes the base material layer 200B and the expansion and contraction inhibitor 200R so that even if the insulating member 200 is attached to the semiconductor substrate 110, The alignment between the first and second auxiliary electrodes P141 and P142 and the first and second electrodes C141 and C142 formed on the rear surface of the semiconductor substrate 110 can be more easily aligned, have.

Therefore, the process time and yield for producing the solar cell can be further improved.

It will be apparent to those skilled in the art that various modifications, substitutions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. will be. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are intended to illustrate and not to limit the technical spirit of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments and the accompanying drawings . The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (19)

Front glass substrate;
A rear sheet disposed on a rear surface of the front glass substrate;
A plurality of solar cells disposed between the front glass substrate and the rear sheet;
A first encapsulant disposed between the plurality of solar cells and the front glass substrate; And
And a second encapsulant disposed between the plurality of solar cells and the back sheet,
Wherein the back sheet comprises a core layer made of an insulating material and a stretching inhibitor having a thermal expansion coefficient lower than that of the core layer. The method according to claim 1,
And the expansion / contraction inhibitor is dispersedly disposed in the core layer. The method according to claim 1,
Wherein the expansion / contraction inhibitor is disposed in the core layer in a mesh form. The method according to claim 1,
Wherein the expansion / contraction inhibitor is formed as a separate layer in the core layer. 5. The method according to any one of claims 1 to 4,
Wherein the core layer comprises a polymer-based material. 6. The method of claim 5,
Wherein the stretching inhibitor comprises at least one of carbon nanotubes, boron nitride, ceramics, and glass fibers. 6. The method of claim 5,
Wherein the rear sheet further comprises a coating layer covering the core layer and performing a moisture-proof function. 8. The method of claim 7,
Wherein the coating layer comprises polyvinyl fluoride (PVF) and polyvinylidene difluoride (PVDF). A semiconductor substrate;
A plurality of first electrodes and a plurality of second electrodes formed on a rear surface of the semiconductor substrate so as to be spaced apart from each other;
And an insulating member having a first auxiliary electrode connected to the plurality of first electrodes and a second auxiliary electrode connected to the plurality of second electrodes,
Wherein the insulating member comprises a base material layer of an insulating material and a contraction inhibitor having a thermal expansion coefficient lower than a thermal expansion coefficient of the base material layer. 10. The method of claim 9,
Wherein the expansion / contraction inhibitor is dispersedly disposed in the base material layer. 10. The method of claim 9,
Wherein the expansion / contraction inhibitor is arranged in a mesh form in the base material layer. 10. The method of claim 9,
Wherein the expansion / contraction inhibitor is disposed by forming a separate layer in the base material layer. 13. The method of claim 12,
Wherein the layer forming the stretch inhibitor is disposed on the front surface of the base material layer. 13. The method of claim 12,
Wherein the layer forming the stretch inhibitor is disposed in the base material layer. 10. The method of claim 9,
Wherein the stretching inhibitor comprises at least one of carbon nanotubes, boron nitride, ceramics, and glass fibers. 10. The method of claim 9,
Wherein the base material layer of the insulating member comprises at least one material selected from the group consisting of a polymer-based material, an epoxy-based material, and a bismaleimide triazine (BT) resin. 10. The method of claim 9,
The first auxiliary electrode
A plurality of first connection parts connected to the first electrode,
And a first pad portion having one end connected to an end of the plurality of first connection portions,
The second auxiliary electrode
A plurality of second connection parts connected to the second electrode,
And a second pad portion having one end connected to an end of the plurality of second connecting portions. 18. The method of claim 17,
The first electrode and the first connection portion, and the second electrode and the second connection portion are electrically connected to each other by an electrode connector. 18. The method of claim 17,
Wherein an insulating layer is formed between the first electrode and the second electrode, and between the first connecting portion and the second connecting portion.

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