JP5227612B2 - Solar cell assembly - Google Patents

Description

  The present invention relates to an assembly of a solar cell that converts incident light by directly guiding or reflecting the incident light to a solar cell element to convert the light into electricity.

  A solar cell generates electricity by its photovoltaic power when a silicon crystal semiconductor or organic semiconductor solar cell element receives light.

  A solar cell using a panel-plate-like silicon crystal semiconductor solar cell element is widely used. This solar cell element is known in which a thin film of p-type silicon crystal containing boron is laminated on a thin film of n-type silicon crystal mixed with arsenic, and electrodes are connected to both thin films. Such a solar cell element is covered with a glass cover or a transparent resin cover such as an acrylic resin or an epoxy resin to form a solar cell assembly. Glass covers are heavy and difficult to mold into any shape and are easy to break, while transparent resin covers are inferior in light resistance, heat resistance, and scratch resistance. Epoxy resin covers, in particular, turn yellow over time and light. Will be blocked. In addition, the light is blocked by the electrode on the incident light side and is not fully utilized. Furthermore, it is troublesome to stack many layers of high-purity crystal thin films, resulting in poor yield and cost.

  A solar cell assembly is also known in which light is focused on a panel cell-like solar cell element using a convex lens or a Fresnel lens. In such a solar cell assembly, light loss due to the reflection of the surface of the solar cell element occurs due to the air layer between the lens and the solar cell element. In addition, since a member such as a lens is present, all of the incident light cannot reach the solar cell element. Moreover, only sunlight directly incident on the solar cell element can be used, and when the sunlight is blocked by the leaves and shade and does not directly enter, the power generation efficiency becomes extremely low.

  Moreover, as a solar cell assembly, as in Patent Document 1, a substantially spherical shape having a first semiconductor layer and a second semiconductor layer outside the first semiconductor layer on the bottom of a support in a recess provided with a coating layer that reflects light. A photovoltaic device in which the photoelectric conversion element is arranged is also known.

  This solar cell assembly can collect a part of the reflected light on the photoelectric conversion element, but if part of the reflected light does not hit the photoelectric conversion element and diffuses again to the outside, the photoelectric efficiency is lowered. Moreover, since the reflective layer is exposed, a decrease in photoelectric efficiency due to contamination is inevitable. Therefore, further improvement in photoelectric efficiency is desired.

Japanese Patent No. 3490969

  The present invention has been made to solve the above-mentioned problems, and is excellent in light resistance and heat resistance without being yellowed or deteriorated even when exposed to strong light or heat for a long period of time, and is durable and scratch resistant. An object is to provide a solar cell assembly that is excellent in productivity, inexpensive, has a long life, is highly reliable, has a high photoelectric conversion efficiency, and has a simple structure that allows incident light to efficiently reach a solar cell element. To do.

The solar cell assembly according to claim 1, which has been made to achieve the above object, includes a resin body having a convex surface and formed of a silicone resin containing a light scattering agent, and the convex surface side. And a metal layer provided along the convex surface, wherein the surface of one semiconductor layer is covered with the other semiconductor layer, and the one semiconductor layer is exposed from the missing portion of the other semiconductor layer. However, the one semiconductor layer is connected to one electrode through the exposed portion and the other semiconductor layer is connected to the other electrode, and is sealed by curing in the resin body, and the metal layer is the other semiconductor layer. Also serving as an electrode, the other semiconductor layer is in contact with the bottom of the concave surface of the metal layer, one semiconductor layer is in contact with the electrode element through the exposed portion, and the solar cell element is disposed, or one of the semiconductor layers An electric wire extends to contact the metal layer, an electric wire extends from the other semiconductor layer, contacts the electrode element through a hole opened in the metal layer, or the solar cell element is disposed, or an electric wire extends from the other semiconductor layer The resin body in which the solar cell element is disposed in contact with the electrode element through a hole that is in contact with the metal layer, extends from one of the semiconductor layers, and is opened in the metal layer, and is sealed The unit is connected by the resin body and the metal layer, the metal layer and the electrode element are insulated, and the silicone resin is based on dimethylorganopolysiloxane and is liquid. It is an addition reaction curable silicone resin obtained by thermally curing the addition reaction curable silicone resin raw material composition .

Solar cell assembly, also serves as a metal layer is the other electrode, in contact with the bottom portion of the concave surface of the other semiconductor layer is the metal layer, the solar one semiconductor layer is in contact with the electrode element through the exposed portion cell element that have been placed.

The solar cell assembly according to claim 2 is the solar cell assembly according to claim 1, wherein the solar cell element has a spherical shape, a plate shape, a column shape, a rectangular parallelepiped shape, a polygonal shape, a conical shape, or a polygonal pyramid shape. It is characterized by that.

The solar cell assembly of claim 3, those described in any one of claims 21 to, before carboxymethyl recone resin, the hardness in Shore D hardness measured according to the method of JIS K 7215 20 It is characterized by being set to ° to 90 ° .
A solar cell assembly according to a fourth aspect is the solar cell assembly according to the first or second aspect, wherein the silicone resin is a gel-like or rubber-like silicone resin.

The solar cell assembly according to claim 5 is the solar cell assembly according to any one of claims 1 to 4 , wherein the silicone resin raw material composition includes the organopolysiloxane as a base polymer and an organohydrogenpolysiloxane. And a catalyst selected from heavy metal catalysts, organometallic compounds, and metal fatty acid salts .
A solar cell assembly according to a sixth aspect is the solar cell assembly according to the fifth aspect , wherein the raw material composition is solvent-free.

A solar cell assembly according to a seventh aspect is the solar cell assembly according to the first aspect, wherein the resin body is in a planar shape, a convex shape, or a Fresnel lens shape at an incident site on a surface opposite to the convex surface. It is characterized by being molded.

The solar cell assembly according to claim 8 is the solar cell assembly according to any one of claims 1 to 7 , wherein the resin body is surface-coated with a polyparaxylylene coating or a fluorine-containing resin coating. It is characterized by being.

The solar cell assembly according to claim 9 is the one described in any one of claims 1 to 8 , wherein the light incident surface of the resin body is a light guide material of any one of a light guide plate and a light guide film, It is laminated or integrated, and the light guide material is wider than the light incident surface.

Solar cell assembly according to claim 10 has been described in claim 9, wherein the light guide member is, inside the region corresponding to the light incident surface of the resin body, contain the light scattering agent It is characterized by being.

A solar cell assembly according to an eleventh aspect is the solar cell assembly according to any one of the first to tenth aspects, wherein the light incident surface of the resin body or the surface of the light guide material is provided with irregularities of nanometer order. By being roughened, the light passing therethrough is scattered.

A solar cell assembly according to a twelfth aspect is the solar cell assembly according to the ninth aspect , wherein the light guide member is separated from the resin body while facing the light incident surface of the resin body. It has the unevenness | corrugation which contains the said light-scattering agent inside, or has light scattering on the surface facing a light-incidence surface.

The method for manufacturing a solar cell assembly according to claim 13 , wherein the surface of one semiconductor layer is covered with the other semiconductor layer to form a solar cell element, and a resin body having a convex surface is formed while enclosing it. The solar cell assembly for manufacturing the solar cell assembly according to claim 1, wherein the convex surface is covered with a metal layer, the metal layer is connected to one of the semiconductor layers, and the other semiconductor layer is connected to the electrode element. a method of manufacturing a silicone resin containing a light scattering agent, to form the resin member, the solar cell element intended you seal the resin body, said silicone resin, dimethylorganopolysiloxane Is an addition reaction curable silicone resin obtained by thermally curing a liquid addition reaction curable silicone resin raw material composition .

The method of manufacturing a solar cell assembly according to claim 14 , wherein a solar cell element in which a surface of one semiconductor layer is covered with another semiconductor layer is formed, and a metal layer is attached to the concave surface of the insulating cup having a concave surface. and, after the contacting the placing a solar cell element metal layer and the other semiconductor layer in the bottom of the concave surface, sealing each said solar cell element the concave portion in the transparent resin, the sun according to claim 1 a manufacturing method of a solar cell assembly to produce a battery assembly, a silicone resin containing a light scattering agent, to form the resin member, intended for sealing the solar cell element in the resin body, the silicone resin, in which a dimethyl organopolysiloxane base polymer, characterized in that the silicone resin raw material composition of the addition reaction curing of the liquid is an addition-curable silicone resin that is thermally cured To.

  The solar cell assembly of the present invention efficiently guides incident light to the solar cell element, and reflects the internal light (total reflection) of the incident light that could not be directly guided to the element to efficiently generate electricity. It can be generated. Therefore, this solar cell assembly can guide incident light from multiple directions to the solar cell element without depending on the direction, so it depends on the incident direction like a large rod-shaped solar cell element or a large sheet-shaped solar cell element. Photoelectric efficiency is much better than the solar cell assembly. In addition, the resin that has a refractive index different from that of air due to sealing refracts light that is incident obliquely and directly reaches the solar cell element or is reflected by a deep large reflective concave surface to indirectly reach the solar cell element. Thus, photoelectric conversion can be performed efficiently.

  This solar cell assembly is light and excellent in light resistance, heat resistance, and impact resistance. The solar cell element is sealed in a resin body made of silicone resin that can be molded into an arbitrary shape. Will not break.

  Moreover, since this solar cell assembly is formed by coating the convex surface of the resin body with a metal layer such as a thin metal foil that has been metal-plated or pressed, it has a simple structure, is lightweight, and is externally It can cope with deformation from Moreover, even if exposed to vibration, it does not break.

  The resin body made of silicone resin has a relatively high refractive index, has a high transmittance with respect to light of various wavelengths such as sunlight, and does not cause deterioration that yellows or deteriorates over time. Therefore, there is little loss of incident light. In addition, since this resin body is stable to light such as infrared rays and ultraviolet rays, water, heat, and vibration, the solar cell assembly does not deteriorate and is light resistant even when exposed to wind and rain or strong sunlight for a long time.・ Excellent durability such as weather resistance and heat resistance, long life and reliability.

  Since this resin body is made of a hard silicone resin or a soft silicone resin gel or rubber, it exhibits excellent light transmission. Has less light loss.

  When the surface of a silicone resin resin body is appropriately undercoated or modified and then coated with plating, the metal plating is excellent in adhesion to the resin body and hardly peels off. Therefore, deformation of the resin body can be dealt with and the reflection efficiency does not decrease. Even if the outer surface of the solar cell assembly is touched, the solar cell assembly is not in direct contact with the reflective concave surface on the inner side of the metal plating and is not contaminated with hand dirt, so that it is easy to handle. In addition, since the silicone resin is not easily charged with static electricity and does not easily interact with dust or dust, the solar cell assembly is not easily contaminated.

  Further, when the silicone resin is a soft gel or rubber, it is flexible and absorbs deformation caused by heat based on the difference in expansion coefficient among members, and absorbs stress caused by artificial bending. Even if bent, it will not break. If the silicone resin is a hard resin, the solar cell assembly will be solid and sturdy.

  When the resin body has a light scattering agent, the light incident on the resin can be scattered to efficiently irradiate the solar cell element. Further, when the light incident surface of the resin body is roughened with fine irregularities on the order of nanometers, light can be efficiently incident from multiple directions and irradiated onto the solar cell element.

  When the light incident surface of the resin body is covered with a light guide material wider than that, not only the light directly incident on the solar cell assembly but also the light applied to the light guide material can be photoelectrically converted efficiently. When the light guide material contains a light scattering agent in a portion corresponding to the light incident surface of the resin body, light from the light guide material is incident on the resin body. Moreover, even if the surface opposite to the light incident surface of the resin body has irregularities for light scattering, light can be efficiently incident on the resin body. In addition, when the light incident surface is roughened with fine irregularities on the order of nanometers, the solar cell element can be irradiated efficiently without being totally reflected from multiple directions. .

  According to the method for manufacturing a solar cell assembly of the present invention, a solar cell assembly can be provided simply, efficiently and inexpensively.

Preferred form for carrying out the invention

  Hereinafter, embodiments of the present invention will be described in detail, but the scope of the present invention is not limited to these embodiments.

  A solar cell assembly according to an embodiment of the present invention will be described with reference to FIG.

  As shown in FIG. 1 (A), the solar cell assembly 1 includes a plurality of resin bodies 4 formed of silicone resin and having convex surfaces arranged in a four-dimensional manner in a close-packed manner in two dimensions. Each downward convex surface is covered with silver plating which is metal plating, and a substantially spherical solar cell element 3 is sealed inside each resin body 4. Although not shown in the figure, a plurality of resin bodies may be arranged at intervals.

  As shown in FIG. 1 (A), the solar cell assembly 1 includes a downwardly convex surface of the resin body 4 and a metal plating 2 coated thereon, a hyperboloid, a paraboloid, an elliptical surface, and a spherical surface that coincide with each other. It has a curved shape like By the metal plating 2, a part of incident light that cannot be directly guided to the solar cell element 3 is reflected and focused on the solar cell element 3.

  In the solar cell assembly 1, as shown in FIG. 1B, the solar cell element 3 may be disposed on the incident surface side and connected to the electrode line.

  As shown in FIG. 2B, which is a cross-sectional view of the solar cell assembly 1, the solar cell element 3 includes an n-type silicon semiconductor having a substantially spherical p-type silicon semiconductor 3 a inside and a PN junction covering the periphery thereof. 3b. The lower end of the n-type silicon semiconductor 3b is polished and missing, and the p-type silicon semiconductor 3a is exposed therefrom. The n-type silicon semiconductor 3b is connected only to the metal plating 2 which also serves as a negative electrode, while the p-type silicon semiconductor 3a is connected only to the electrode element 7 which is a positive electrode through a non-plating portion opened at the bottom of the metal plating 2. Connected. The metal plating 2 and the electrode element 7 which are both electrodes are isolated and insulated by an insulator layer 5 laminated therebetween.

  The resin body 4 is made of polydimethylsiloxane, which is a transparent silicone resin, and seals the solar cell element 3 while being buried. Although the surface shape of the incident part of the resin body 4 can take any shape, it is planar in FIG.

Although the example in which the solar cell element 3 has a substantially spherical shape is shown, it may be a true spherical shape, a plate shape, a column shape, a rectangular parallelepiped shape, a polygonal shape, a conical shape, or a polygonal pyramid shape. The solar cell element 3 may be disposed inside the resin body 4 in contact with the metal layer 2 as shown in FIGS. 1 (A) and 2. Solar cell element 3, as shown in FIG. 3 (B), is disposed near the center of the resin member 4, from one of the semiconductor layer 3a wire 9a is extended upward in contact with the metal layer 2, the other semiconductor layer An electric wire 9b may extend from 3b downward and may be led out from the insulator layer 5 through a hole opened in the metal layer 2. Solar cell element 3, as shown in FIG. 3 (C), is disposed near the center of the resin member 4, the wire 9b from the semiconductor layer 3b of the other side is extended into contact with the metal layer 2, hand semiconductor layer An electric wire 9 a may extend from 3 a downward and be led out from the insulator layer 5 through a hole opened in the metal layer 2.

  The semiconductors 3a and 3b may be polycrystalline silicon crystals, but may be organic semiconductors.

  The solar cell assembly 1 will be manufactured as described below with reference to FIGS. 1 (A) and 2.

First, a silicon sphere is produced by thinning an n-type silicon crystal around a spherical p-type silicon crystal. A metal mold having a large number of dents for making a plurality of resin bodies having convex surfaces arranged in order in four directions is manufactured. A second recess in which a portion of the silicon sphere fits somewhat in each recess is prepared. Silicon spheres are put there, and a liquid raw material composition of silicone resin is poured and cured to form a member in which a large number of resin bodies 4 containing silicon spheres are arranged. A film as a masking material is stuck on the upper plane. It is removed from the mold, and then polyparxylylene “Parylene C” (trade name, manufactured by Japan Parylene Co., Ltd .; “Parylene” is a registered trademark; — [(CH ₂ ) —C ₆ H ₃ Cl— (CH ₂ )] _n- ) to form a coating, a powdered monochloroparaxylylene dimer, which is a raw material dimer of “Parylene C”, is placed in a vaporization chamber and heated under reduced pressure. After forming a radical of a highly reactive paraxylylene monomer induced in the thermal decomposition chamber, it is deposited on the convex side of the resin body 4 to coat a polyparaxylylene coating of 0.5 to 5 microns, preferably 1 to 2 microns. Process to form an undercoat layer. A metal plating 2 having a thickness of several microns is formed on the convex surface of the resin body 4 by vacuum deposition. The silicon sphere remains slightly protruding from the convex surface of the resin body 4, and the n-type silicon semiconductor 3b is in contact only with the metal plating 2 that also serves as the negative electrode. Thereafter, the masking material is peeled off. As shown in FIG. 2A, the vicinity of the apex of the silicon sphere protruding from the convex surface of the resin body 4 is polished flatly, the outer n-type silicon semiconductor 3b is missing, and the inner p-type silicon semiconductor 3a is exposed from the missing portion. Let The n-type silicon semiconductor 3b remains in contact only with the metal plating 2 that also serves as the negative electrode. The positive electrode element 7 is attached to the exposed portion. At that time, when the positive electrode element 7 and the energizing element 6 attached so as to cover the insulator layer 5 are brought into contact with each other, the solar cell assembly 1 as shown in FIG.

  This solar cell assembly 1 is used as follows. As shown in FIG. 2B, light, for example, sunlight 10 is vertically incident on the solar cell element 3 of the solar cell assembly 1. For example, incident sunlight 10 b from directly above passes through the resin body 4 straightly and is guided vertically to the top of the solar cell element 3. Incident sunlight 10c slightly deviated from directly above passes through the resin body 4 and is reflected by the side surface of the solar cell element 3, and further reflected by the metal plating 2 and guided substantially vertically to the surface near the bottom of the solar cell element 3. The incident sunlight 10 a that is considerably off from directly above is transmitted through the resin body 4, reflected by the metal plating 2, and guided substantially vertically to the side surface of the solar cell element 3. In this way, the light incident on the solar cell assembly 1 efficiently reaches the PN junction interface between the n-type silicon semiconductor 3b and the p-type silicon semiconductor 3a, and a photoelectromotive force is generated. Flows.

  In addition, although the example of polydimethylsiloxane was shown as a silicone resin for shape | molding the resin body 4 of the solar cell assembly 1, another silicone resin like polydiphenylsiloxane may be used.

  The resin body 4 can be obtained, for example, by curing a raw material composition of a silicone resin. As the raw material composition of the silicone resin, a liquid addition reaction curable silicone resin raw material composition is particularly preferable. A liquid addition reaction curable silicone resin raw material composition is preferable because it is solvent-free and can be cured uniformly on the surface and inside without foaming.

  The raw material composition of the addition reaction curable silicone resin is not particularly limited as long as it forms a transparent silicone resin by thermosetting. For example, an organopolysiloxane is used as a base polymer, and an organohydrogenpolysiloxane and Examples include those containing a heavy metal catalyst such as a platinum catalyst.

Examples of the organopolysiloxane include the following average unit formula R _a SiO _{(4-a) / 2}
Wherein R is an unsubstituted or substituted monovalent hydrocarbon group, preferably having 1 to 10 carbon atoms, particularly 1 to 8. a is a positive number of 0.8 to 2, particularly 1 to 1.8. Number.)
The thing shown by is mentioned. Here, R is an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, an alkenyl group such as a vinyl group, an allyl group or a butenyl group, an aryl group such as a phenyl group or a tolyl group, or an aralkyl such as a benzyl group. A halogen-substituted hydrocarbon group such as a chloromethyl group, a chloropropyl group, or a 3,3,3-trifluoropropyl group in which some or all of the hydrogen atoms bonded to these carbon atoms are substituted with a halogen atom, Or a cyano group-substituted hydrocarbon group such as a 2-cyanoethyl group substituted with a cyano group, and R may be the same or different, but those containing a phenyl group as R, particularly all R Among them, those in which 5 to 80 mol% is a phenyl group are preferable from the viewpoint of heat resistance and transparency.

  Further, those containing an alkenyl group such as a vinyl group as R, particularly those in which 1 to 20 mol% of all R are alkenyl groups are preferred, and those having two or more alkenyl groups in one molecule are preferably used. It is done. Examples of such organopolysiloxane include terminal alkenyl group-containing diorganopolysiloxanes such as dimethylpolysiloxane having a terminal alkenyl group such as vinyl group and dimethylsiloxane / methylphenylsiloxane copolymer, A liquid at room temperature is preferably used.

  On the other hand, the organohydrogenpolysiloxane is preferably trifunctional or higher (that is, one having three or more hydrogen atoms (Si-H groups) bonded to a silicon atom in one molecule), for example, methylhydrogenpolysiloxane. , Methylphenyl hydrogen polysiloxane, and the like, and liquids at room temperature are particularly preferable. Examples of the catalyst include platinum, platinum compounds, organometallic compounds such as dibutyltin diacetate and dibutyltin dilaurate, and metal fatty acid salts such as tin octenoate. The types and amounts of these organohydrogenpolysiloxanes and catalysts may be appropriately determined in consideration of the degree of crosslinking and the curing rate.

  The silicone resin may be those described in JP-A-2004-221308, JP-A-2006-328102, JP-A-2006-328103, and JP-A-2006-324596.

  In addition to the above components, fillers, heat-resistant materials, plasticizers and the like may be added to the extent that the strength and transparency of the resulting silicone resin are not impaired.

  As the raw material composition of the silicone resin, commercially available products such as KJR632 manufactured by Shin-Etsu Chemical Co., Ltd. can be used.

  The resin body 4 can be obtained by a conventionally known method of forming the raw material composition into a silicone resin molded body, and can be molded by, for example, cast molding. In addition, the hardness of the silicone resin of the resin body 4 is 20 ° to 90 °, particularly 50 ° to 80 ° in Shore D hardness measured by the method of JIS K 7215 (Plastic Durometer Hardness Test Method). Is preferred.

  The transmittance of the silicone resin is preferably 90% or more, and more preferably 92% or more. The transmittance of the resin body 4 molded with polydimethylsiloxane is about 94%, and the transmittance of the resin body 4 molded with polydiphenylsiloxane is about 92%. The transmittance is maintained even when used for a long time. The transmittance of the resin body 4 molded with an epoxy resin is 92%, but it changes to yellow and decreases to 60% or less due to long-term use. When the resin body 1 is formed of a hard silicone resin such as polydimethylsiloxane, it is difficult to expand and is not easily deteriorated on the short wavelength side such as ultraviolet rays, and is suitable for maintaining optical characteristics. preferable. The resin body 1 preferably has a Shore D hardness of 15 ° or more.

  Further, the silicone resin may be a silicone rubber which is the same kind as such a hard silicone resin and is crosslinked with a relatively low molecular weight organopolysiloxane. The silicone rubber preferably has a Shore A hardness of 50 ° to 90 °. When metal plating is directly deposited on the internal reflection portion 10 at a high temperature under reduced pressure at a high temperature under reduced pressure, the low molecular siloxane gas volatilized from the resin body 4 causes the resin body 4 to become cloudy. Will reduce the reflectivity. Therefore, the silicone rubber resin body 4 is washed with an organic solvent such as 1-bromopropane and trichloroethylene, and the pressure is reduced, or the temperature is reduced to, for example, 150 ° C. or higher, preferably 150 to 200 ° C. It is preferable that a pretreatment for volatilization is performed. Secondary vulcanization treatment or solvent extraction treatment may be performed.

  In particular, when the resin body 4 is made of silicone rubber, volatile components such as moisture and low-molecular siloxane are likely to remain, and it is preferable to volatilize them.

  When the silicone resin is a silicone rubber, it is preferable to use a chemical vapor deposition (CVD) method in which vapor deposition is performed at a low temperature because when the metal film is coated, when the temperature is applied, the resin expands and becomes wrinkled.

  In order to improve the adhesion between the resin body 4 and the metal plating 2, an example in which a polyparaxylylene coating is applied and primed with “Parylene C” has been shown. “Parylene N” (trade name, manufactured by Japan Parylene Co., Ltd.) obtained from xylylene dimer, and “Parylene D” (trade name, manufactured by Parylene Japan Ltd.) obtained from tetrachloroparaxylylene dimer may be used. . Even if this raw material dimer is sublimated by heating to about 600 ° C. under a low pressure, a highly reactive paraxylylene radical gas is generated and vapor-deposited and coated with a polyparaxylylene coating. Good. Among these, it is more preferable that polyparxylylenes are coated with “Parylene C”. The thickness of the undercoat layer of these polyparaxylylenes is, for example, 5 to 3000 nm, but is preferably 50 to 2000 nm, and more preferably 100 to 1000 nm.

  In addition, the primer agent used for the primer treatment is not particularly limited as long as it can firmly provide a light reflecting portion on the surface of the silicone, but optically even when exposed to strong light or heat for a long time. As a material which does not deteriorate, a primer treatment agent such as hexamethyldisilazane, hexamethyldisiloxane and / or tetraethylorthosilicate is preferable. It is preferable to apply these to silicone and perform primer treatment, and then provide a metal layer.

  The modification by the polyparaxylylene coating treatment is most preferable, but the modification by the ultraviolet irradiation treatment with an ultraviolet lamp is also preferable instead. It may be modified by any one of corona treatment by corona discharge under atmospheric pressure or reduced pressure, plasma treatment by glow discharge under reduced pressure, or flame treatment with a burner flame. .

  Metal plating containing a metal such as silver, aluminum, nickel, or chromium on the surface of the resin body 4 that has been primed or modified by chemical vapor deposition, chemical plating, sputtering, or ion plating. Is preferably formed. About nickel and chromium, metal plating is preferable, for example, the thickness is 1 to 100 microns, preferably 1 to 10 microns.

  The metal layer provided at the reflection site in the present invention may be metal deposition, electroless plating, silver mirror reaction, or a method of applying a thin metal foil or pressing a thin metal foil or plate.

  The refractive index of the resin body 4 is preferably such that the difference between air and the refractive index is 0.05 or more. The refractive index of the resin body 4 of silicone resin is preferably 1.41 to 1.57.

  As shown in FIG. 4, the solar cell assembly 1 covers the downward convex surface of the resin body 4 with a metal plating 2, and the electrode element 7 is applied to one of the semiconductors via the flat insulator layer 5. It may be an integral type in contact.

  Moreover, the unit may be connected by the resin body and the metal layer constituting a continuous body with the resin body in which the solar cell element is sealed as a unit. Further, the units may be two-dimensionally arranged in a close-packed manner, and may be arranged in a hexagonal honeycomb shape on the incident surface. Moreover, single substance may be provided apart from each other in a wide light guide material, and the light may be collected by the light guide material and scattered in the scattered solar cell elements.

  In the solar cell assembly 1, an example in which the upper surface side of the resin body 4 made of silicone resin is flat and the lower surface side is convex and the entire convex surface is covered with the metal plating 2 is shown in FIG. 5A. Further, the resin body 4 may be covered with a protective plate 8 made of silicone resin which is hard, gel-like or rubber-like soft. As shown in FIG. 4B, the upper resin body having an upward convex surface made of a hard, gel-like, or rubber-like soft silicone resin on the lower resin body 4a having a downward convex surface as the resin body 4. 4b may be covered and integrated. Further, as shown in FIG. 5C, the lower resin body 4a having a downward convex surface is covered with a Fresnel lens-shaped upper resin body 4b made of a hard, gel-like, or rubber-like soft silicone resin. It may be converted into one.

  At least a part of the incident portion of the resin body 4 may be covered with a polyparaxylylene film or a fluorine-containing resin film.

  When the resin body 4 is surface-coated with the polyparaxylylene film or the fluorine-containing resin film having a small friction coefficient and dielectric constant, the resin body 4 may be exposed to strong sunlight or the like. Even if static electricity, heat, or plasma is generated on the surface, it is difficult to cause deterioration of the silicone resin of the resin body 4, deterioration of the surface of the resin body 4, and the like. Therefore, even if the resin body 4 is exposed to sunlight or the like for a long time under the sun, there is no risk of being darkened and soiled or deteriorated, allowing light to be transmitted efficiently and further extending the life of the solar cell assembly 1. In addition, since the polyparaxylylene coating is uniformly deposited, it is excellent in thermal stability, light transmission, scratch resistance, cold resistance, chemical resistance, and ultraviolet resistance. There is no deterioration such as deterioration and excellent durability.

  The resin body 4 is uniformly coated with this film even if the incident site is planar, convex, or Fresnel lens-shaped.

  Further, this coating prevents surface reflection at a wavelength to be transmitted or blocks transmission at a specific wavelength according to the optical path distance of the polyparaxylylene coating.

  Since the solar cell assembly 1 having the resin body 4 to which this film is applied can make a sufficient amount of light incident on the solar cell element 3, the photoelectric conversion efficiency is extremely good. Moreover, since a sufficient amount of light can be incident on the solar cell element 3 stably for a long time without darkening, there is no need for troublesome parts replacement.

For example, the resin body 4 is covered with a coating of “Parylene C” (trade name, manufactured by Japan Parylene Co., Ltd .; Parylene is a registered trademark), which is a chlorine-containing polyparaxylylene. More specifically, the resin body 4 is coated as follows. On the surface of the resin body 4, a coating of “Parylene C” (trade name, manufactured by Japan Parylene Co., Ltd .; Parylene is a registered trademark; — [(CH ₂ ) —C ₆ H ₃ Cl— (CH ₂ )] _n −) Form. For example, a powdered monochloroparaxylylene dimer that is a raw material dimer of “Parylene C” is placed in a vaporization chamber and heated under reduced pressure, and the evaporated dimer is guided to a thermal decomposition chamber to produce highly reactive paraxylylene. After forming into radicals of the lenmon monomer, a film of polyparaxylylene is formed by vapor deposition on the silicone resin and polymerization, and the resin body 4 is obtained.

In addition, although the resin body 4 showed the example vapor-deposited with the coating of the polyparaxylylenes which are "parylene C", it replaced with "parylene C" and "parylene N obtained from paraxylylene dimer (DPX) was shown. "(Trade name manufactured by Japan Parylene Co., Ltd.)" or "Parylene D" (trade name manufactured by Japan Parylene Co., Ltd.) obtained from tetrachloroparaxylylene dimer may be used. The dimer as the raw material may be heated to about 600 ° C. under a low pressure to be sublimated to generate a highly reactive paraxylylene radical gas and vapor deposited to form a polyparaxylylene film. Among them, it is more preferable that a film of polyparaxylylene is deposited by “Parylene C”. The refractive index n _d ²³ of these polyparaxylylenes is, for example, “Parylene N” is 1.661 and “Parylene C” is 1.639, and the refractive index of silicone resin is 1.41 to 1.57 or epoxy resin. The refractive index is higher than 1.55 to 1.61. Therefore, optical characteristics such as surface reflection prevention can be adjusted by appropriately selecting the resin body 4 that transmits visible light, for example, light having a wavelength λ, and an optical distance that is an integer multiple of the parylene and λ of the coating material.

  The coating of polyparaxylylene can be uniformly prepared to a desired thickness by adjusting the amount of raw material dimer and the deposition time.

  According to the vapor deposition of such polyparaxylylenes, there is no need to heat the silicone resin as the base material, so there is no fear that the silicone resin is thermally deformed. In addition, since the deposition and polymerization of diparaxylylene radicals on the silicone resin proceed at the same time, the manufacturing process is short and simple.

  The polyparaxylylenes have been shown as being applied to a silicone resin by vapor deposition, but may be applied by dipping, spray coating, spin coating, sputtering, or application.

  The resin body 4 may contain a light scattering agent. Examples of the light scattering agent include inorganic powders such as silica powder and calcium carbonate powder, and organic powders such as acrylic resin powder. Among them, the light scattering agent is preferably commercially available porous silica, fumed silica, or calcium carbonate powder showing a high light scattering coefficient. The average particle size is preferably about 200 to 7000 nm. The light scattering agent is preferably contained in an amount of 0.01 to 4% by mass.

  The resin body 4 may be formed into a planar shape, a convex shape, or a Fresnel lens shape at an incident site opposite to the reflecting concave surface, and there is a nanometer order, for example, 50 to 2000 nm, preferably 200 to 800 nm, More preferably, irregularities having a surface roughness of 400 to 500 nm may be provided. Within this range, surface reflection is eliminated and photoelectric efficiency is improved.

  Concavities and convexities on the order of nanometers are formed on a mold used to mold a resin body 4 into a planar, convex, or Fresnel lens shape at an incident site opposite to the reflecting concave surface. Electron beam lithography processing, blast processing, nano It can be formed by applying a concavo-convex process such as a spray coating process or a chemical etching process in which a composition containing fine particles having a metric order diameter is sprayed. In particular, if the resin body 4 is a silicone resin, the transferability is good, so that the unevenness of the mold can be accurately inverted to form nanometer-order unevenness at the incident portion of the resin body 4.

  As shown in FIG. 6, the solar cell assembly 1 may be covered with a light guide material 11 such as a light guide plate or a light guide film. It is preferable that the light guide member 11 covers the solar cell assembly 1 and is applied over a wider range. Thereby, even if light is not directly incident on the solar cell assembly 1, when light is incident on the light guide member 11, photoelectric conversion can be efficiently performed. The light guide material 11 may have irregularities of the nanometer order as described above. Examples of the material of the light guide material 11 include polyacrylic resins, silicone resins, polyester resins such as polyethylene terephthalate, fluorine-containing resins, and polycarbonate resins, and silicone resins are particularly preferable. The end face other than the light incident surface of the light guide plate or the light guide film, which is the light guide material 11, or the opposite surface is covered with a reflective material such as plating or a titanium oxide film so that the light incident on the corner is not leaked from the light guide material 11. It is preferable that The solar cell assembly 1 may have a member that supports the light guide member 11. The light scattering agent 12 may be contained in the resin body 4 of the solar cell assembly 1. The light scattering agent 12 may be contained in the light guide agent 11.

  The solar cell assembly 1 may be covered with an antireflection coating.

  The light guide material 11 may be integrated with the resin body 4 by, for example, integral molding. In that case, the light scattering agent exemplified as being contained in the resin body 4 may be contained in the light guide material.

  The light guide member 11 may be separated from the resin body 4 while facing it. In that case, if the light scattering agent 12 exemplified as what is contained in the resin body 4 is contained in the light guide material facing the light incident surface of the resin body 4, the resin from the containing portion of the light scattering agent 12. Light is emitted toward the light incident surface of the body 4. Similarly, when unevenness is provided on the surface of the light guide material 11 facing the light incident surface of the resin body 4, light is scattered at the uneven portion and similarly light is emitted toward the light incident surface of the resin body 4. The unevenness may have, for example, the same nanometer order or larger unevenness as described above. Further, the surface of the light guide plate containing the light scattering agent facing the light incident surface of the resin body 4 may have irregularities on the order of nanometers or larger.

  The adhesive used as necessary in the present invention is preferably a transparent agent that is stable against the heat and light of the semiconductor, and is preferably a silicone adhesive.

  The method of molding the resin body is not particularly limited as long as it can be molded by injection molding or mold molding, but mold molding in which silicone is poured into the mold is preferable.

  An example of a prototype of the solar cell assembly of the present invention is shown below.

Example 1
As the solar cell element, a commercially available substantially spherical solar cell element having a conductive wire formed by covering the surface of one semiconductor layer with the other semiconductor layer and connecting to the one semiconductor layer was used. A 1 mm thick polycarbonate is hot-pressed to form a cup with the concave surface, and the cup edge becomes a hexagonal honeycomb to form an outer edge that is closely packed on a flat surface. A continuous insulating layer base material was prepared. The bottom of the concave surface of each cup of the base material was concealed with a sealing masking material slightly smaller than the other semiconductor layer of the solar cell element, and silver plating was performed. The seal-like masking material was peeled off, and a hole through which the conductor was passed was made. Place the solar cell element on it, bring the other semiconductor layer into contact with the silver plating, pass the lead wire through the hole in the insulating layer base material, and separate both semiconductor layer layers so that they are not in direct contact with the insulating layer base material. Fixed. The silicone resin raw material composition containing organopolysiloxane was poured into the concave surface of each cup of the base material until each cup was covered, and then the resin was thermally cured to seal the solar cell element with a transparent resin body. The solar cell assembly shown in FIG.

(Example 2)
Except that the silicone resin raw material composition of Example 1 contains a light scattering agent of calcium carbonate and was cured, the incident surface was formed with a mold with irregularities on the order of nanometers. A solar cell assembly was obtained.

(Example 3)
A disk-shaped light guide plate 20 times the area of the incident surface of the solar cell assembly obtained in Example 1 is attached to the incident surface side with a silicone rubber having a thickness of 3 mm to obtain the solar cell assembly shown in FIG. It was.

Example 4
A solar cell assembly was obtained in the same manner as in Example 1 using the silicone resin raw material composition of Example 1 containing a light scattering agent. A disk-shaped light guide plate 20 times the area of the incident surface was attached to the incident surface side to obtain a solar cell assembly. In creating this disk-shaped light guide plate, nano-order irregularities with an average height of 50 nm were applied to the surface on which sunlight was incident. The material inside the portion of the light guide plate corresponding to the light incident surface of the resin body in which the solar cell element was sealed was filled with amorphous silica having an average particle shape of 3000 nm and calcium carbonate 1% each. The opposite surface where sunlight does not enter and the end surface of the light guide plate were covered with a silicone resin film containing 70% titanium oxide.

(Comparative example)
The same procedure as in Example 1 was performed except that the solar cell element was not sealed with a resin composition on the concave surface of each cup of the base material of Example 1.

  In all examples, photoelectric conversion was improved as compared with the comparative example. In addition, the effect became greater as Example 4 was reached than Example 1.

  The solar cell assembly of the present invention can be mounted on a roof of a house, a portable electronic device, an automobile, an artificial satellite, or the like because it has a high photoelectric conversion efficiency and can be provided on a substrate having an arbitrary shape.

It is a perspective view which shows one form of the solar cell assembly to which this invention is applied. It is sectional drawing of the solar cell assembly to which this invention is applied. It is sectional drawing which shows the form of another solar cell assembly to which this invention is applied. It is sectional drawing which shows the form of another solar cell assembly to which this invention is applied. It is sectional drawing which shows the form of another solar cell assembly to which this invention is applied. It is sectional drawing which shows the form of another solar cell assembly to which this invention is applied.

Explanation of symbols

  1 is solar cell assembly, 2 is metal plating, 3 is solar cell element, 3a is p-type silicon semiconductor, 3b is n-type silicon semiconductor, 4 is resin body, 4a is lower resin body, 4b is upper resin body, 5 is An insulating layer, 6 is a conductive element, 7 is an electrode element, 8 is a protective plate, 9a and 9b are electrodes, 10, 10a, 10b, and 10c are sunlight, 11 is a light guide, and 12 is a light scattering agent.

Claims (14)

It has a resin body formed of a silicone resin having a convex surface and containing a light scattering agent, and a metal layer provided along the convex surface on the convex surface side, and the surface of one semiconductor layer is the other semiconductor A solar cell element that is covered with a layer and one semiconductor layer is exposed from a missing portion of the other semiconductor layer, the one semiconductor layer is connected to one electrode through the exposed portion, and the other semiconductor layer is the other electrode And being sealed by curing in the resin body,
The metal layer also serves as the other electrode, the other semiconductor layer is in contact with the bottom of the concave surface of the metal layer, and one semiconductor layer is in contact with the electrode element through the exposed portion, so that the solar cell element is disposed. ,
Or the electric wire extends from one semiconductor layer and contacts the metal layer, the electric wire extends from the other semiconductor layer and contacts the electrode element through a hole opened in the metal layer, the solar cell element is disposed,
Or the electric wire extends from the other semiconductor layer and contacts the metal layer, the electric cell extends from one semiconductor layer and contacts the electrode element through the hole opened in the metal layer, the solar cell element is disposed,
The resin body in which the solar cell element is sealed as a unit is connected by the resin body and the metal layer, and the metal layer and the electrode element are insulated ,
A solar cell assembly , wherein the silicone resin is based on dimethylorganopolysiloxane and is an addition reaction curable silicone resin obtained by thermally curing a liquid addition reaction curable silicone resin raw material composition .   The solar cell assembly according to claim 1, wherein the solar cell element has a spherical shape, a plate shape, a column shape, a rectangular parallelepiped shape, a polygonal shape, a conical shape, or a polygonal pyramid shape. Before SL silicone resin, the solar cell assembly according to any claim 21 to the, characterized in that the 20 ° to 90 ° and the hardness in Shore D hardness measured according to the method of JIS K 7215.   The solar cell assembly according to claim 1, wherein the silicone resin is a gel-like or rubber-like silicone resin. The silicone resin raw material composition includes an organohydrogenpolysiloxane and a catalyst selected from a heavy metal catalyst, an organometallic compound, and a metal fatty acid salt while using the organopolysiloxane as a base polymer. Item 5. The solar cell assembly according to any one of Items 1 to 4. The solar cell assembly according to claim 5 , wherein the raw material composition is solvent-free.   2. The solar cell assembly according to claim 1, wherein the resin body is molded into a planar shape, a convex shape, or a Fresnel lens shape at an incident site on a surface opposite to the convex surface. It said resin body, with a film coating or a fluorine-containing resin polyparaxylylene such, solar cell assembly according to any one of claims 1 to 7, characterized in that it is surface-coated. The light incident surface of the resin body is laminated or integrated with any one of a light guide plate and a light guide film, and the light guide material is wider than the light incident surface. The solar cell assembly according to any one of claims 1 to 8 . 10. The solar cell assembly according to claim 9 , wherein the light guide member contains the light scattering agent in a portion corresponding to a light incident surface of the resin body. On the surface of the light incident surface or the light guide member of the resin member, by the unevenness of the nanometer order is assigned is in arara, 1 to claim, characterized in that to scatter light passing therethrough 10 A solar cell assembly according to any one of the above. The light material, are separated while facing to the resin body, is light scattering in the surface facing the contain the light scattering agent to the inside of the region corresponding to the light incident surface of the resin member or the light incident surface It has an unevenness | corrugation, The solar cell assembly of Claim 9 characterized by the above-mentioned. The surface of one semiconductor layer is covered with the other semiconductor layer to form a solar cell element, a resin body having a convex surface is formed while enclosing it, and the convex surface is covered with a metal layer, and the metal layer is A method of manufacturing a solar cell assembly for manufacturing the solar cell assembly of claim 1, wherein the solar cell assembly is manufactured by connecting to one semiconductor layer and connecting another semiconductor layer to the electrode element.
In a silicone resin containing a light scattering agent, the resin body is formed and the solar cell element is sealed in the resin body, and the silicone resin is based on dimethylorganopolysiloxane, A method for producing a solar cell assembly, which is an addition reaction curable silicone resin obtained by thermally curing a liquid addition reaction curable silicone resin raw material composition . A solar cell element in which the surface of one semiconductor layer is covered with the other semiconductor layer is formed, a metal layer is attached to the concave surface of the insulating cup having a concave surface, and the solar cell element is placed on the bottom of the concave surface A method of manufacturing a solar cell assembly for manufacturing the solar cell assembly according to claim 1, wherein after the metal layer is brought into contact with the other semiconductor layer, the concave surface portion is sealed together with the solar cell element with a transparent resin. ,
In a silicone resin containing a light scattering agent, the resin body is formed and the solar cell element is sealed in the resin body, and the silicone resin is based on dimethylorganopolysiloxane, A method for producing a solar cell assembly, which is an addition reaction curable silicone resin obtained by thermally curing a liquid addition reaction curable silicone resin raw material composition .

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