KR101212352B1 - Back sheet for a solarcell module having an excellent heat-discharging property and preparing process thereof - Google Patents

Abstract

The present invention provides a solar cell back sheet having excellent heat dissipation characteristics by forming a layer containing at least one kind of geometric isomeric organic compound on at least one surface of the base layer to easily lower the temperature in the solar cell module, and the solar cell back sheet. It relates to a solar cell module comprising a back sheet and a method for manufacturing the solar cell back sheet, the solar cell back sheet excellent in the heat dissipation characteristics of the present invention described above for a solar cell comprising a substrate layer of one layer or a multilayer structure of a polymer substrate In the back sheet, the back sheet is characterized in that it consists of a multi-layered structure of a resin layer comprising a geometric organic compound applied to the base layer and one or both sides of the base layer.
The solar cell backsheet having the excellent heat dissipation characteristics of the present invention configured as described above is merely formed with an organic compound layer on at least one surface of the base layer, without a problem in manufacturing technology or a conventional problem such as a decrease in adhesive strength of the sheet. Since it is possible to significantly suppress the temperature rise of the solar cell module by excellent properties, as a result, it is possible to provide a solar cell back sheet and a solar cell including the back sheet which can maintain the temperature in the solar cell module lower than conventional. The present invention solves the problems of the prior art by providing a solar cell which can improve the power generation efficiency due to the temperature characteristics of the semiconductor device.

Description

Back sheet for a solar cell module having an excellent heat-discharging property and preparing process etc.

The present invention relates to a solar cell backsheet having excellent heat dissipation characteristics and a method of manufacturing the same, and more particularly, to form a layer including at least one or more types of geometric isomeric organic compounds on at least one side of the substrate layer to increase the temperature in the solar cell module. The present invention relates to a solar cell back sheet having excellent heat dissipation characteristics which can be easily lowered, a solar cell module including the solar cell back sheet, and a manufacturing method of the solar cell back sheet.

Recently, solar cells using the sun have been in the spotlight recently because they overcome energy shortages of limited energy resources and do not cause environmental pollution in an environmentally friendly manner. In solar cells, semiconductor devices that convert light energy into electrical energy by using a photoelectric effect are often manufactured using a single crystalline silicon or a polycrystalline silicon base. It must have the ability to protect the device from external factors such as moisture, oxygen, chemicals and dust, and a lighter and thinner structure is preferred in terms of device efficiency.

Therefore, as a material capable of satisfying the requirements for use as such a backsheet, a sheet derived from a polymer is known to be the most suitable until now, and in practice, a polymer is commonly used for most backsheet components. However, one polymer alone has not been able to fully satisfy the above various requirements as a backsheet, so traditionally the backsheet has a multi-layered structure of materials that give it a unique role. Such a multi-layer backsheet generally has a structure in which a weather resistant film is grounded on the outer side of the hydrolysis resistant barrier layer and an electrical insulation layer is grounded on the cell side. In the barrier layer, a plastic film including polyester and an aluminum thin film are mainly used. In addition to the barrier function, the barrier layer serves as a mechanical support.

However, when the solar cell module including the back sheet as described above is installed outdoors, the temperature of the solar cell module is 50 ° C. as the heat is generated by the operation of the semiconductor device even if the ambient temperature is normal at the time of actual power generation. It rises to the above. By the way, when the temperature of the solar cell module rises above a certain temperature, there is a problem that the power generation efficiency is significantly lowered due to the temperature characteristics of the semiconductor device.

Therefore, various attempts have been proposed to solve the above problems. For example, Japanese Patent No. 193-181333 is provided with a film having a high thermal emissivity of irregularities on the surface of the back side of a solar cell module. Proposing a technique to get. However, it is difficult to obtain sufficient heat dissipation characteristics because it is difficult in manufacturing technology to give a large uneven shape to the film. As another example, Japanese Patent No. 2010-027714 proposes a technique of forming a metal foil on a back sheet and Japanese Patent No. 2009-170772 to form a high thermal conductive film on the back sheet to impart high thermal conductivity to the back sheet. have. However, the above method is not only a problem that the manufacturing cost of the back sheet is increased, but also the adhesive strength with the ethylene vinyl acetate copolymer (EVA) sheet located on the upper part of the back sheet when manufacturing the solar cell module is not good, various treatment Through the disadvantage that the adhesion to the ethylene vinyl acetate copolymer (EVA) sheet to be improved. In addition, the Republic of Korea Patent Application No. 2009-0030479 is provided on at least one side of the "polyester-based substrate layer and the polyester-based substrate layer in order to improve the heat storage and heat dissipation functionality, heat storage including a heat storage material and a heat dissipating material The solar cell backsheet including the sheet layer "is disclosed, but there is still a problem that the method also does not effectively exhibit heat dissipation characteristics.

As described above, the backsheet of the conventional solar cell module has a number of excellent advantages but still have a number of problems to be solved, that is, to improve the heat dissipation characteristics, the adhesion between the backsheet and the ethylene vinyl acetate copolymer sheet In order to improve the quality of the problem, it has been suggested as an essential task to be solved.

Patent Document 1: Japanese Patent No. 193-181333 Patent Document 2: Japanese Patent No. 2010-027714 Patent Document 3: Japanese Patent No. 2009-170772 Patent Document 4: Republic of Korea Patent Application No. 2009-0030479

Accordingly, the present invention has been made in view of the above technical problems in the prior art, and the main object of the present invention is that there is no problem in manufacturing technology in the manufacture of a solar cell back sheet, and other problems such as a decrease in adhesive strength of the sheet do not occur. It is to provide a solar cell back sheet that can effectively exhibit excellent heat dissipation characteristics.

Another object of the present invention is to provide a solar cell module using a solar cell back sheet having the above excellent characteristics.

Still another object of the present invention is to provide an easy method for manufacturing a solar cell back sheet having the above excellent characteristics.

The present invention may also be directed to accomplishing other objects that can be easily derived by those skilled in the art from the overall description of the present specification, other than the above-described and obvious objects.

The object of the present invention described above is that when the present inventors install the solar cell module outdoors as described above, the temperature of the solar cell module rises as heat is generated by the operation of the semiconductor device, and thus Recognizing the problem that the power generation efficiency is lowered due to the temperature characteristics of the semiconductor device when the temperature is increased, and also in the situation that economic and easy backsheet manufacturing technology is required, the layer of the layer containing the geometric organic compound Forming it was found that the above-mentioned conventional problems can be solved, and could be achieved by providing a backsheet having high adhesion with ethylene vinyl acetate copolymer (EVA), and in the present invention constituted as described above, geometric isomeric organic compounds By applying a layer containing a to the base material layer was able to realize excellent heat dissipation characteristics and ultimately The present invention has been completed to improve the power generation efficiency of the battery module.

Solar cell back sheet excellent in the heat radiation characteristics of the present invention for achieving the above object;

In the back sheet for a solar cell comprising a substrate layer of one layer or a multilayer structure of a polymer substrate,

The back sheet is characterized in that it consists of a multi-layered structure of a resin layer comprising a geometric organic compound applied to the base layer and one side or both sides of the base layer.

According to another configuration of the present invention, the geometric isomeric organic compounds are selected from cis ethylene dicarboxylate (maleate) or trans ethylene dicarboxylate (fumarate), each compound having the following structural formula: Shall be:

Where R is H or C ₁ An alkyl group having C ₈ ;

Where R is as defined above.

According to another configuration of the present invention, the base layer is polyethylene (PE), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyethylene naphthalate (PEN), polyvinyl fluoride (PVF), polyvinyl Monolayers, homogeneous multilayers, using one selected from the group consisting of lidene fluoride (PVDF), ethylene tetrafluoroethylene (ETFE), polychlorotrifluoroethylene (PCTFE), ethylenechlorotrifluoroethylene (ECTFE) or inorganic compounds, Or it is characterized in that formed in a heterogeneous multilayer.

According to another configuration of the present invention, the ratio of the cis-type and trans-type isomers of the structural formula is characterized in that the trans type is used a lot.

According to another configuration of the invention, the amount of the geometric isomer is characterized in that it is used in 0.01mmol / ㎡ to 100mmol / ㎡ relative to the area.

Solar cell module with excellent heat dissipation characteristics for achieving another object of the present invention;

A module comprising a backsheet for a solar cell comprising a substrate layer of one layer or a multilayer structure of a polymer substrate, wherein the backsheet comprises a geometric organic compound applied to the substrate layer and one or both surfaces of the substrate layer. It is characterized by consisting of a multi-layer structure of the layer.

Method for producing a solar cell back sheet having excellent heat dissipation characteristics for achieving another object of the present invention;

A geometric isomeric organic compound selected from cis ethylene dicarboxylate (maleate) or trans ethylene dicarboxylate (fumarate), a compound having the following structural formula, together with resins such as polyester, polyacrylic and polyurethane Compounding; And

The blended resin is polyethylene (PE), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyethylene naphthalate (PEN), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), ethylene At least one surface of a base layer formed of a monolayer, homogeneous multilayer, or heterogeneous multilayer selected from the group consisting of tetrafluoroethylene (ETFE), polychlorotrifluoroethylene (PCTFE), ethylenechlorotrifluoroethylene (ECTFE) or an inorganic compound To apply a film to form a film;

Where R is H or C ₁ An alkyl group having C ₈ ;

Where R is as defined above.

The solar cell backsheet having the excellent heat dissipation characteristics of the present invention configured as described above is merely formed with an organic compound layer on at least one surface of the base layer, without a problem in manufacturing technology or a conventional problem such as a decrease in adhesive strength of the sheet. Since it is possible to significantly suppress the temperature rise of the solar cell module by excellent properties, as a result, it is possible to provide a solar cell back sheet and a solar cell including the back sheet which can maintain the temperature in the solar cell module lower than conventional. The present invention solves the problems of the prior art by providing a solar cell which can improve the power generation efficiency due to the temperature characteristics of the semiconductor device.

1 is a cross-sectional view showing a cross section of a solar cell module according to an embodiment of the present invention,
2 is a cross-sectional view showing a cross section of a solar cell module according to another embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail with reference to attached drawing by preferred embodiment.

1 and 2 are cross-sectional views each showing a cross section of a solar cell module according to a preferred embodiment of the present invention.

As shown in the figure, the solar cell backsheet layers 14 and 24 according to the preferred embodiment of the present invention are polyethylene (PE) layer 16, polyethylene terephthalate (PET) layer 17, polyvinylidene fluorine The geometric organic compound layer (PVDF) layer 26, polyethylene terephthalate (PET) layer 27, polyvinylidene fluoride (PVDF) layer 28 is laminated on at least one side of the base layer formed by 15, 25) is formed and used, the geometric organic compound layer according to the present invention, the ethylene dicarboxylate is present in the resin in a certain ratio in the cis-type and trans-type. In addition, the geometric isotropic organic compound according to the present invention may change the geometric molecular structure from the trans form to the cis form through an endothermic reaction. At this time, the activation energy according to the molecular structure change of maleic acid (Maleic acid) and fumaric acid (Fumaric acid), a representative material of ethylene dicarboxylate is 66.1kJ / mol, enthalpy change is 22.7kJ / mol. That is, the trans-type ethylene dicarboxylate absorbs heat corresponding to 22.7 kJ / mol in the solar cell module, and the molecular structure changes to cis-type, thereby suppressing the temperature rise of the solar cell.

In addition, the cis-type ethylenedicarboxylate produced by the conversion has a steric structurally strong polarity (dipole moment: 10.6ⅹ10 ^-30 C? M), and thus an ethylene vinyl acetate copolymer (EVA) located on the backsheet. It is possible to obtain the effect of improving the adhesive force with.

As described above, the change in the geometrical molecular structure between the trans ethylene dicarboxylate and the cis ethylene dicarboxylate is reversible, and activation energy is changed when the molecular structure changes from the more unstable cis form to the stable trans form. Is 43.4 kJ / mol, and an exothermic reaction occurs with an enthalpy change of -22.7 kJ / mol. In the above exothermic reaction, the generation of solar cells is stopped at night when there is no sunlight, and when heat generation is relatively stopped, the conversion to a more stable isomer form proceeds, thereby regenerating the trans-type ethylene dicarboxylate. The enthalpy outflow between these transformations is shown in the diagram below.

Fumaric Maleic Acid

According to another preferred embodiment of the present invention, the geometric isomeric compound can be formed using any of the cis-type and trans-types in an arbitrary ratio, and it is preferable to use a trans-type.

In addition, the amount of the geometric isomeric compound is preferably used in 0.01mmol / ㎡ to 100mmol / ㎡ relative to the area. If less than 0.01 mmol / m 2, sufficient heat dissipation properties are not secured. On the contrary, if more than 100 mmol / m 2 is used, the process is difficult, not economical, and the mechanical stability of the geometric organic compound layer is not secured. This will affect the quality of the product. More preferably, it is preferable to use the amount per area of 1 mmol / m 2 to 50 mmol / m 2.

The geometric isomeric organic compound prepared according to the embodiment of the present invention is blended with a resin such as polyester, polyacryl, polyurethane, polyethylene (PE), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), Polyethylene naphthalate (PEN), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), ethylenetetrafluoroethylene (ETFE), polychlorotrifluoroethylene (PCTFE), ethylenechlorotrifluoroethylene (ECTFE Or a substrate layer formed of a single layer, homogeneous multilayer, or heterolayer selected from the group consisting of inorganic compounds to form a film, using a method commonly applied in the art such as spin coater, gravure coater, and lip coater. You will be able to use it without difficulty.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but it goes without saying that the scope of the present invention is not limited to these Examples.

Example 1

A solution made by blending a trans ethylene dicarboxylate 1: 1 with a polyester resin was coated on a PE surface of a base layer composed of PE / PET using a lip coater to a thickness of 5 μm to prepare a solar cell backsheet.

Example 2

A solution made by blending a trans-type ethylene dicarboxylate 1: 1 with a polyester resin was coated on one PVDF surface of a substrate layer composed of PVDF / PET / PVDF with a lip coater at a thickness of 5 μm to form a solar cell backsheet. Prepared.

Comparative Example 1

Except for coating a solution made by blending a trans-type ethylene dicarboxylate 1: 1 with the polyester resin in Example 1 in the same manner as in Example 1 in the configuration of PE / PET bag for solar cells Sheets were prepared.

Comparative Example 2

In the same manner as in Example 2, except that the solution prepared by mixing the trans-type ethylene dicarboxylate 1: 1 with the polyester resin in Example 2 in the same manner as in Example 2 PVDF / PET / PVDF A battery backsheet was prepared.

Experimental Example 1

In order to examine the heat dissipation characteristics of the solar cell backsheets prepared in the above Examples and Comparative Examples, a crystalline Si type solar cell module using the backsheet was manufactured under the same conditions. Each solar cell module was separated by the same distance from the halogen lamp light source, and the surface glass of the solar cell module was installed to face the light source, and left for a certain time to reach a thermal equilibrium state.

In addition, the results of measuring the thermal equilibrium temperature using an infrared thermometer (M74KE-574F, Shirotec Co., Ltd.) in the backsheet direction are shown in Table 1 below.

division Example 1 Example 2 Comparative Example 1 Comparative Example 2 Temperature (℃) 48.5 54.5 50.3 56.1

From the results shown in Table 1, by forming the geometric organic compound layer according to the present invention, the thermal equilibrium temperature could be lowered by about 2 ° C., and it was proved that the solar cell backsheet of the present invention had excellent heat dissipation characteristics.

Experimental Example 2

The experimental results of measuring the adhesive strength of the EVA sheet and the backsheet by measuring the peel strength (ASTM D903) of the EVA sheet and the backsheet using the module measured in Experimental Example 1 are shown in Table 2 below.

division Example 1 Example 2 Comparative Example 1 Comparative Example 2 Adhesion ◎ ○ ○ △

◎: very good, ○: excellent, △: normal

From the above test results, it can be seen that the solar cell back sheet according to the present invention can improve the adhesive force with the EVA sheet, and the heat dissipation property and the adhesive force property with the EVA sheet are improved at the same time, which is useful as a back sheet of the solar cell module. It can be seen that it can be used.

11, 21: front glass
12, 22: solar cell
13, 23: ethylene vinyl acetate copolymer (EVA) layer
14, 24: backsheet layer
15, 25: geometric organic compound layer
16: polyethylene (PE) layer
17: polyethylene terephthalate (PET) layer
26: polyvinylidene fluoride (PVDF) layer
27: polyethylene terephthalate (PET) layer
28: polyvinylidene fluoride (PVDF) layer

Claims (7)

delete In the back sheet for a solar cell comprising a substrate layer of one layer or a multilayer structure of a polymer substrate,
The backsheet is composed of a multilayered structure of a resin layer comprising the base layer and a geometric organic compound coated on one or both surfaces of the base layer, wherein the geometric organic compounds are each a compound having the following structural formula: A solar cell back sheet having excellent heat dissipation characteristics, characterized in that selected from phosphorus cis ethylene dicarboxylate (maleate) or trans ethylene dicarboxylate (fumarate):

Wherein R is H or an alkyl group having C ₁ -C ₈ ;

Where R is as defined above.
The method of claim 2, wherein the base layer is polyethylene (PE), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyethylene naphthalate (PEN), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), ethylenetetrafluoroethylene (ETFE), polychlorotrifluoroethylene (PCTFE), ethylenechlorotrifluoroethylene (ECTFE) or a monolayer using one selected from the group consisting of inorganic compounds, homogeneous multilayers, or heterogeneous A solar cell back sheet having excellent heat dissipation characteristics, characterized in that formed in multiple layers.
The backsheet for solar cell having excellent heat dissipation characteristics according to claim 2, wherein the proportion of the cis-type and trans-type isomers of the structural formula is 50% by weight or more than 50% by weight of the trans type.
The backsheet for solar cell having excellent heat dissipation characteristics according to claim 2, wherein the geometric isomer is used in an amount of 0.01 mmol / m 2 to 100 mmol / m 2 relative to the area.
A module comprising a backsheet for a solar cell comprising a substrate layer of one layer or a multilayer structure of a polymer substrate, wherein the backsheet comprises a geometric organic compound applied to the substrate layer and one or both surfaces of the substrate layer. Layered structure, wherein the geometric isomeric organic compound is selected from cis ethylene dicarboxylate (maleate) or trans ethylene dicarboxylate (fumarate), each compound having the following structural formula: Solar cell module with excellent heat dissipation characteristics:

Wherein R is H or an alkyl group having C ₁ -C ₈ ;

Where R is as defined above.
A geometric isomeric organic compound selected from cis ethylene dicarboxylate (maleate) or trans ethylene dicarboxylate (fumarate), a compound having the following structural formula, together with resins such as polyester, polyacrylic and polyurethane Compounding; And
The blended resin is polyethylene (PE), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyethylene naphthalate (PEN), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), ethylene At least one surface of a base layer formed of a monolayer, homogeneous multilayer, or heterogeneous multilayer selected from the group consisting of tetrafluoroethylene (ETFE), polychlorotrifluoroethylene (PCTFE), ethylenechlorotrifluoroethylene (ECTFE) or an inorganic compound Method for producing a solar cell back sheet having excellent heat dissipation characteristics characterized in that it comprises the step of forming a film by coating;

Where R is H or C ₁ An alkyl group having C ₈ ;

Where R is as defined above.

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