JPH09162435A - Filter for solar battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the temperature rise of a solar battery by equipping this filter with infrared-ray screen layers made of transmitting wavelength selecting agents which intercept the infrared rays in specified wavelength region, on one side or both sides of a transparent base material layer. SOLUTION: Infrared ray screen layers 2 made of the transmitting wavelength selecting agents constituted of zinc oxides or the like which intercepts the infrared ray L1 (1200<L1<300nm, or 1200<=L1<=3000nm) in the wavelength region of at least 1200-300nm are made on one side or both sides of a transparent base material layer 1. The temperature rise of the solar battery by heat beam can be suppressed by forming infrared ray screen layers 2 (filters), which transmit the beam of wavelength of 400-1200nm required for power generation and intercept the heat beam of wavelength of 1200-300nm unnecessary for power generation out of the solar ray, on the incidence side of the solar battery.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided on the light incident side of a solar cell that receives sunlight to generate electricity (converts it into electric energy), and is one of the causes of the reduction in power generation efficiency. The present invention relates to a filter for a solar cell that improves the power generation efficiency by cutting light rays.

[0002]

2. Description of the Related Art In general, a solar cell, as shown in FIG.
A transparent glass plate, a synthetic resin plate, or a metal plate (not shown) such as an opaque stainless plate is used as the support substrate 11, and the surface electrode 12 (transparent electrode) provided on the light incident side of the substrate 11 is opposed to the surface electrode 12. The junction between the p-type semiconductor layer P having positive charge holes and the n-type semiconductor layer N having weak valence electrons (-charges) between the rear surface electrode 13 (metal electrode) and A semiconductor light receiving portion PN (photoelectric conversion layer) made of a pn junction type semiconductor is provided.

The power generation by the solar cell utilizes the photoelectric effect (photovoltaic effect) that occurs when natural light from sunlight or artificial illumination light such as a fluorescent lamp or an incandescent lamp is incident on the semiconductor light receiving portion PN. Is.

When a light ray L (including visible light) having an appropriate wavelength is incident on the pn junction surface of the semiconductor light receiving portion PN in a direction perpendicular or parallel to the junction surface, the light is present in the n-type semiconductor layer N. The extra valence electrons having weak bonding force become free electrons and move toward the p-type semiconductor layer P having holes, and the semiconductor light receiving portion PN has an electrode on the p-type semiconductor layer P side (the surface electrode 12). ) Is the cathode, and the electrode on the n-type semiconductor layer N side (rear surface electrode 1
Photovoltaic (potential difference) with 3) as the anode + is generated to generate power, and the current i flows through the load.

The current conversion efficiency of solar cells into photovoltaic power depends on the type of solar cell, but is as shown in Table 1 below.

[0006]

[Table 1]

The Si-based (single crystal type, polycrystal type, amorphous type, etc.) semiconductor light receiving portion is relatively inexpensive, and particularly, the amorphous silicon type (a-Si type) is used.
The system) is particularly inexpensive, but the conversion efficiency is 20% or less. On the other hand, GaAs-based (gallium / arsenic-based) has a conversion efficiency of 29% obtained by condensing light.

In order to increase the efficiency of the solar cell, it is sufficient to accept as much solar energy as possible. For example, an antireflection layer is provided on the surface of the cell body on the light incident side. In order to collect as much solar energy as possible into the semiconductor light receiving part, we have taken measures such as taking in as much light as possible and providing a reflective layer on the back side of the battery body so that incident light does not escape. it can.

[0009]

However, since the semiconductor light receiving portion of the solar cell also absorbs infrared rays from the sun's rays, the temperature of the solar cell rises and the conversion efficiency is lowered. .

Here, the short-circuit current value Isc (unit: A) and the open-circuit voltage value Voc of the standard solar cell with respect to temperature, respectively.
FIG. 7 shows the relationship between (unit: V) and relative output value Wrc (unit: W).

The short-circuit current value Isc gradually increases with temperature, but the open circuit voltage value Voc decreases, so that the relative output value Wrc (Wrc = Isc × Voc) decreases.

According to FIG. 7, a solar cell used under sunlight has a relative output value of 1 W when the surface temperature is 28 ° C.
When the temperature rises to 48 ° C, it becomes 0.9W and 10
%, A decrease in output is seen, and in solar cells for concentrating and for space use, preventing temperature rise due to infrared rays becomes a problem.

Further, the concentrating solar cell can improve the efficiency of conversion into electric energy by improving the concentrating rate of solar energy by using a concentrator, a sun tracking device, a support, and the like. It is possible, but if the temperature rises with the increase of the light collection rate, the conversion efficiency will decrease.

When the light collection rate is relatively low, the conversion efficiency increases with the light collection rate. However, when the light collection rate further increases, the open circuit voltage Voc decreases due to the temperature rise.
The relative output value Wrc decreases and the conversion efficiency decreases, and the problem is to prevent the temperature rise due to infrared rays.

An object of the present invention is to improve the power generation efficiency (conversion efficiency) by cutting the heat rays of the sun rays, which is one of the causes of the decrease in power generation efficiency.

[0016]

Means for Solving the Problems A first invention of the present invention is:
On one side or both sides of the transparent substrate layer 1, at least 120
Infrared ray L1 in the wavelength range of 0 to 3000 nm (1200 <
L1 <3000 nm or 1200≤L1 ≤3000
The solar cell filter is characterized by including an infrared shielding layer 2 formed of a transmission wavelength selective agent that shields (nm).

The second invention of the present invention is the transparent substrate layer 1
On one or both sides of at least 1200-3000
Infrared rays in the wavelength region of nm L1 (1200 <L1 <300
Infrared ray shielding layer 2 formed of a transmission wavelength selective agent for shielding 0 nm or 1200 ≦ L1 ≦ 3000 nm)
And a UV-shielding layer 3 formed of a transmission wavelength-selecting agent that shields UV L2 (L2 <400 nm or L2 ≤ 400 nm) in a wavelength region of at least 400 nm, respectively. .

Next, a third invention of the present invention is a transparent substrate layer 1
Infrared ray L1 (1200 <L1 <3000 nm or 12 in the wavelength range of at least 1200 to 3000 nm)
It is a filter for a solar cell in which a transmission wavelength selective agent for shielding (00≤L1≤3000 nm) is kneaded.

Next, a fourth invention of the present invention is to provide a transparent substrate layer 1
Infrared ray L1 (1200 <L1 <3000 nm or 12 in the wavelength range of at least 1200 to 3000 nm)
00≤L1≤3000 nm) and at least 400 nm
It is a filter for a solar cell in which a transmission wavelength selection agent for shielding ultraviolet rays L2 (L2 <400 nm or L2 ≤ 400 nm) in a smaller wavelength region is kneaded.

The present invention is also the above-mentioned first to fourth inventions, wherein an antireflection layer is provided on the outermost layer of the transparent base material layer 1, the infrared shielding layer 2 and the ultraviolet shielding layer 3 of the filter. 4 is a solar cell filter provided.

In the first to fourth inventions of the present invention, the transmission wavelength selective agent for shielding infrared rays L1 is a metal oxide such as tin oxide or zinc oxide or magnesium oxide, or gold, silver, Or any of these 2
It is a filter for a solar cell which has an inorganic material as a main component such as a mixture of at least one kind.

The present invention is also the above-mentioned second or fourth invention, wherein the transmission wavelength selective agent for shielding the ultraviolet ray L2 is zinc oxide, cerium oxide or titanium oxide, or any two of them. It is a filter for solar cells whose main component is an inorganic substance such as the mixture as described above.

Further, the present invention is the solar cell filter according to any one of the first to fourth inventions, wherein the transmission wavelength selecting agent is mainly composed of an ultrafine powder of an inorganic substance having a particle size of 500 Å or less.

The present invention is also the above-mentioned first to fourth inventions, wherein the front surface or the back surface of the supporting substrate of the solar cell having a semiconductor light receiving portion for converting incident light rays into electric energy on the transparent supporting substrate. Is a filter for a solar cell, which is provided in the solar cell and cuts the heat rays of the incident light rays to suppress the temperature rise of the solar cell.

The present invention is also directed to the surface electrode (transparent electrode) of a solar cell according to any one of the first to fourth inventions, which has a semiconductor light receiving portion for converting incident light rays into electric energy on a transparent supporting substrate. A filter for a solar cell, which is provided on the surface and suppresses a heat ray of an incident light ray to suppress a temperature rise of the solar cell.

The present invention is also directed to the surface electrode (transparent electrode) of a solar cell according to any one of the first to fourth inventions, which has a semiconductor light receiving portion for converting incident light rays into electric energy on an opaque supporting substrate. A filter for a solar cell, which is provided on the surface and suppresses a heat ray of an incident light ray to suppress a temperature rise of the solar cell.

Further, according to the present invention, in the above-mentioned first to fourth inventions, the surface of a transparent protective plate of a solar cell provided with a semiconductor light receiving portion for converting incident light rays into electric energy on an opaque supporting substrate, or A filter for a solar cell, which is provided on the back surface and suppresses the heat rays of incident light rays to suppress the temperature rise of the solar cell.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION The solar cell filter of the present invention will be described in detail below according to the embodiments.

The light rays required for power generation by the solar cell are
Generally, as shown in the graph of the relationship between the wavelength of the light beam and the light output of the solar cell shown in FIG.
It is light with a wavelength of 00 nm.

Light rays called heat rays in the sunlight are near infrared rays (wavelength: 700 to 3000 nm).

The filter for a solar cell of the present invention transmits the rays of the wavelength of 400 to 1200 nm, which are necessary for power generation, out of the sunlight, and 1200 nm to 300 which is unnecessary for power generation.
It is designed to block (cut) heat rays having a wavelength of 0 nm. By providing this filter on the light incident side of the solar cell, the temperature rise of the solar cell due to the heat rays is suppressed. .

The solar cell filter of the present invention comprises 400
A light having a wavelength of ˜1200 nm (not necessarily including 1200 nm and wavelengths in the vicinity thereof) is transmitted, and 120
It shields wavelengths of 0 nm and above, and p
It is provided in a semiconductor light receiving portion made of an n-junction semiconductor. The p-type semiconductor and the n-type semiconductor constituting the semiconductor light receiving portion of the solar cell are crystalline (single crystal or polycrystal) or amorphous (noncrystalline) Si (silicon) based semiconductors, respectively. Used.

The solar cell filter of the present invention has a transparent synthetic resin film (sheet) as a base material, and 1200 in a synthetic resin material (70 to 90 parts by weight) constituting the base material.
or a transparent synthetic resin film in which a transmission wavelength selection agent (10 to 30 parts by weight) that blocks infrared rays having a wavelength of not less than nm (not necessarily including wavelengths of 1200 nm and its vicinity) is kneaded The transmission wavelength selective agent (10 to 30 parts) in the synthetic resin liquid (70 to 90 parts by weight, of which the solvent content is 20 to 30 parts by weight) of the synthetic resin and the solvent is formed on the front surface or both front and back surfaces of the (sheet). (Part by weight) is applied, or a film (70 to 90 parts by weight of synthetic resin material and 10 to 30 parts by weight of the same transmission wavelength selection material) in which the same transmission wavelength selection agent is kneaded is laminated to form an infrared ray. The shielding layer 2 is formed, and thereby 400 to
It transmits light having a wavelength of 1200 nm and blocks wavelengths of 1200 nm or more (not necessarily including 1200 nm and wavelengths in the vicinity thereof).

The transmission wavelength selective agent for shielding infrared rays having a wavelength of 1200 nm or more is tin oxide, a metal oxide such as zinc oxide or magnesium oxide, a metal such as gold or silver, or any two of them. The main component is an inorganic material such as the above mixture. Further, it is appropriate that the transmission wavelength selection agent contains an ultrafine powder of an inorganic substance having a particle diameter of 500 Å or less as a main component.

The inorganic substance may be carbon black, antimony oxide, indium oxide, or other metal oxides belonging to Periodic Tables 4A, 5A and 6A.

The solar cell filter of the present invention comprises:
Using a transparent synthetic resin film (sheet) as a base material, as described above, it transmits the light rays having a wavelength of 400 to 1200 nm necessary for power generation and shields infrared heat rays having a wavelength of 1200 nm or more, which is unnecessary for power generation. And in the base material, 40
Kneaded with a transmission wavelength selection agent for shielding (cutting) ultraviolet rays having a wavelength of 0 nm or less (wavelengths of 400 nm and wavelengths in the vicinity thereof are not necessarily included), or both front and back surfaces of the base material Is coated with the same transmission wavelength selecting agent or is laminated with a film in which the same transmission wavelength selecting agent is kneaded.
Light having a wavelength of up to 1200 nm is transmitted, and wavelengths having a wavelength of 400 nm or less (wavelengths of 400 nm and its vicinity are not necessarily included) are blocked.

As the transmission wavelength selecting agent for shielding the ultraviolet rays, an inorganic substance such as a metal oxide of zinc oxide, cerium oxide or titanium oxide can be used as a main component, and the particle diameter as the transmission wavelength selecting agent is 500 Å or less. It is suitable to use the ultrafine powder of No. 3 as a main component.

The solar cell filter of the present invention is described below.
A detailed description will be given according to the embodiment shown in FIGS.

FIG. 2A is a side cross-sectional view showing the laminated structure of the filter F of the present invention, in which 1200 is formed on the surface of the transparent base material layer 1 made of a synthetic resin such as polyethylene terephthalate.
Infrared shielding layer 2 by coating a transmission wavelength selective agent that shields infrared heat rays having a wavelength of nm or more as a coating, or laminating a film in which a transmission wavelength selective agent is kneaded, or sputtering vapor deposition of the transmission wavelength selective agent. Is provided.

As shown in FIG. 2 (b), the back surface of the base material layer 1 is coated with a transmission wavelength selection agent that shields ultraviolet rays having a wavelength of 400 nm or less, or a transmission wavelength selection agent is applied. The ultraviolet-shielding layer 3 is provided by laminating the kneaded film or vapor-depositing the transmission wavelength selection agent thereof. The ultraviolet shielding layer 3
Can be provided as needed.

Further, as shown in FIG. 2 (c), a transmission wavelength selective agent for shielding ultraviolet rays having a wavelength of 400 nm or less is applied as a paint on the surface of the infrared shielding layer 2 formed on the base material layer 1. Alternatively, a film in which a transmission wavelength selection agent is kneaded is laminated, or the transmission wavelength selection agent is deposited by sputtering to provide the ultraviolet shielding layer 3. The ultraviolet shielding layer 3 can be provided if necessary.

The solar cell filter F of the present invention is also used.
Is the filter F shown in FIGS.
Alternatively, FIGS. 2D to 2F described in the following examples.
In order to suppress the surface reflection of the incident light on the surface of any one of the filters F shown in FIG. The antireflection layer 4 may be provided by forming saw-toothed concavities and convexities (depth 2 to 6 μm) having an angle of 45 ° or more by a press embossing method or an etching method. The antireflection layer 4 may be formed of a transparent multilayer film in which a high refractive index substance and a low refractive index substance are alternately deposited (sputtered) in multiple layers.

The thickness of each of the transparent base material layer 1, the infrared ray shielding layer 2, the ultraviolet ray shielding layer 3 and the antireflection layer 4 in the solar cell filter of the present invention is not particularly limited, but within a range in which proper layer strength can be obtained. Then, set as thin as possible,
It is desirable to consider so as not to impair the yield of light rays. For example, the transparent base material layer 1 has a thickness of about 20 to 100 μm, the infrared shielding layer 2 has a thickness of about 3 to 10 μm, and the ultraviolet shielding layer 3 has a thickness of 1.
About 10 to 10 μm, and about 5 to 10 μm is suitable for the antireflection layer 4.

[0044]

EXAMPLES Specific examples of the solar cell filter F of the present invention will be described in detail below.

<Example 1> As shown in FIG. 2 (a), a polyethylene terephthalate film having a thickness of 25 μm (manufactured by Toray Industries, Inc., a highly transparent type) was used as a base material layer 1, and an acrylic resin was provided on one surface thereof. An inorganic substance 2a (25 parts by weight) containing fine particles of tin oxide having a particle size of 50 to 100Å as a main component is used as a transmission wavelength selection agent for shielding infrared rays in a binder resin (100 parts by weight) made of an organic solvent. The added coating material was applied and dried to form an infrared shielding layer 2 having a film thickness of 3 μm, to prepare a solar cell filter F of the present invention.

Example 2 As shown in FIG. 2 (b), a polyethylene terephthalate film having a thickness of 25 μm (manufactured by Toray Industries, Inc., a highly transparent type) was used as a base material layer 1, and an acrylic resin was provided on one surface thereof. An inorganic substance 2a (25 parts by weight) containing fine particles of tin oxide having a particle size of 50 to 100Å as a main component is used as a transmission wavelength selection agent for shielding infrared rays in a binder resin (100 parts by weight) made of an organic solvent. Transmitted wavelength selection that shields ultraviolet rays in a binder resin (100 parts by weight) made of polyethylene resin and organic solvent on the other surface by applying the added coating material and drying it to form an infrared shielding layer 2 with a film thickness of 3 μm As an agent, a coating material containing an inorganic substance 3a (25 parts by weight) containing fine particles of zinc oxide having a particle size of 100 to 250 Å as a main component is applied to form an ultraviolet shielding layer 3 having a film thickness of 2 μm. Thick You create a filter F for the battery.

Example 3 As shown in FIG. 2 (c), a polyethylene terephthalate film having a thickness of 25 μm (manufactured by Toray Industries, Inc., a highly transparent type) was used as the base material layer 1 and the film thickness was 3 μm on each side. Infrared shielding layer 2 and film thickness 2μ
A solar cell filter F of the present invention was prepared in the same manner as in Example 2 except that the m ultraviolet blocking layer 3 was laminated.

Example 4 As shown in FIG. 2 (d), polyethylene terephthalate resin (100 parts by weight) was added to
Particle size 50 to 1 as a transmission wavelength selection agent that blocks infrared rays
Inorganic substance 2a whose main component is fine powder of tin oxide of 00Å
(25 parts by weight) was added, kneaded, and melt-extruded to form a film having a thickness of 25 μm as a base material layer 1, and a polyethylene resin and a binder resin made of an organic solvent (100 parts by weight) were used to form an ultraviolet ray on one surface of the film. A coating containing the inorganic substance 3a (25 parts by weight) containing fine particles of zinc oxide having a particle size of 100 to 250Å as a main component is applied as a transmission wavelength selecting agent for shielding light rays to form an ultraviolet shielding layer 3 having a film thickness of 2 μm. Then, the filter F for a solar cell of the present invention was formed.

Example 5 As shown in FIG. 2 (e), a polyethylene terephthalate resin (100 parts by weight) was used.
As a transmission wavelength selective agent that blocks ultraviolet rays, a particle size of 100-
Inorganic substance whose main component is 250Å zinc oxide fine powder 3
a (25 parts by weight) is added and kneaded, and a film having a thickness of 25 μm formed by melt extrusion is used as the substrate layer 1, and on one surface thereof, in a binder resin (100 parts by weight) of a polyethylene resin and an organic solvent, An infrared shielding layer having a film thickness of 3 μm is obtained by applying a coating material containing an inorganic substance 2a (25 parts by weight) containing fine particles of tin oxide having a particle diameter of 50 to 100Å as a main component as a transmission wavelength selection agent for shielding infrared rays. Form 2,
A solar cell filter F of the present invention was prepared.

Example 6 As shown in FIG. 2 (f), polyethylene terephthalate resin (100 parts by weight) was added to
Particle size 50 to 1 as a transmission wavelength selection agent that blocks infrared rays
Inorganic substance 2a whose main component is fine powder of tin oxide of 00Å
(25 parts by weight) resin mixed with polyethylene terephthalate resin (100 parts by weight) as an inorganic material mainly containing fine powder of zinc oxide having a particle size of 100 to 250Å as a transmission wavelength selection agent for blocking ultraviolet rays. 3a (25 parts by weight)
And a resin mixed with each other are kneaded together to form a film (base material layer 1) having a thickness of 25 μm by melt extrusion.
A solar cell filter F of the present invention was prepared.

<Seventh Embodiment> The first embodiment (see FIG. 2A), the second embodiment (see FIG. 2B), or the third embodiment.
In FIG. 2C, one or both layers of the infrared shielding layer 2 and the ultraviolet shielding layer 3 are formed by a vapor deposition method such as vacuum vapor deposition or sputtering vapor deposition, and the vapor deposition method is used. Silver, titanium, as a transmission wavelength selection agent that shields infrared rays when forming the infrared shielding layer 2.
Examples 1 to 1 except that any inorganic substance of copper was used and the inorganic substance made of zinc oxide was used as a transmission wavelength selection agent that shields ultraviolet rays when forming the ultraviolet shielding layer 3 by the vapor deposition method. In the same manner as in 3, the solar cell filter F of the present invention was prepared.

<Embodiment 8> The ultraviolet shielding layer 3 in the above Embodiment 4 (see FIG. 2 (d)) is formed by a vapor deposition method such as vacuum vapor deposition or sputtering vapor deposition, and the ultraviolet shielding layer 3 is formed by the vapor deposition method. A solar cell filter F of the present invention was produced in the same manner as in Example 4 except that an inorganic substance made of zinc oxide was used as a transmission wavelength selection agent that shields ultraviolet rays.

<Embodiment 9> The infrared shielding layer 2 in the above Embodiment 5 (see FIG. 2 (e)) is formed by a vapor deposition method such as vacuum vapor deposition or sputtering vapor deposition, and the infrared shielding layer 2 is formed by the vapor deposition method. A solar cell filter F of the present invention was prepared in the same manner as in Example 5 except that an inorganic substance selected from the group consisting of silver, titanium and copper was used as a transmission wavelength selection agent for shielding infrared rays.

<Embodiment 10> Above Embodiments 1 to 9
The filter F produced by the above method is directly embossed with a saw-toothed concavo-convex pattern on one surface of the filter F by press embossing, or is vapor-deposited (sputtering) on one surface of the filter F to form a transparent film having a thickness of about 4 μm A silicon thin film is formed, and sawtooth-shaped irregularities are formed on the vapor deposition surface (for example, the transparent silicon thin film surface is etched to a depth of 2 to 4 μm).
By forming a saw-toothed concavo-convex pattern of about m), an antireflection layer 4 for preventing reflection (surface reflection) of incident light rays is provided, and a solar cell filter F of the present invention is produced.
(See FIGS. 3A to 3C)

<Embodiment 11> Embodiments 1 to 9 described above.
As shown in FIG. 4, the filter F prepared by the above method is applied to a transparent support substrate 11 (glass plate) through a surface electrode 12 (transparent electrode) through pn junction type semiconductor light receiving portions N and P (single crystal or polycrystal type). Of the Si type or the amorphous Si type (a-Si)) is overlapped on the surface (light incident side) of the supporting substrate 11 (glass plate) on the light incident side of the solar cell, and the periphery of the battery is appropriately formed. A solar cell equipped with the filter F was prepared by fixing with a fixing member or an adhesive (for example, a transparent one-component epoxy adhesive or a two-component curing epoxy adhesive) as necessary.

<Twelfth Embodiment> The first to ninth embodiments described above.
The filter prepared by the above is pn-mounted on an opaque support substrate (stainless steel plate) through the back electrode 13 (metal electrode).
Junction type semiconductor light receiving part (single crystal or polycrystal type Si
Surface electrode 12 formed on the light-incident side of a solar cell having a system or an amorphous Si system (a-Si))
The solar cell was mounted on the surface (light-incident side) of the (transparent electrode), and the peripheral portion of the cell was appropriately fixed with a fixing member or a transparent adhesive if necessary, to prepare a solar cell equipped with the filter F.

<Embodiment 13> As shown in FIG. 4, the filter F prepared in the above Embodiment 10 has the antireflection layer 4 as the outermost surface on the light incident side, and the transparent support substrate 11 is formed.
The surface (light incident side) of the support substrate 11 on the light incident side of a solar cell having a pn junction type semiconductor light receiving portion (single crystal Si system) on a (glass plate) via a surface electrode (transparent electrode). ), The peripheral portion of the battery was appropriately fixed through a fixing member or an adhesive as necessary, and a solar cell equipped with the filter F was prepared.

<Example 14> The filter prepared in Example 10 was pn-bonded on the opaque support substrate (stainless steel plate) via the back electrode with the antireflection layer 4 as the outermost surface on the light incident side. Type semiconductor light receiving part (single crystal S
(i-type) solar cell equipped with a surface electrode (transparent electrode) surface (light incident side) formed by coating on the light incident side, and the peripheral portion of the cell is appropriately fixed with a fixing member or an adhesive as necessary. A solar cell fixed with the filter F attached was prepared.

<Embodiment 15> As shown in FIG. 5, aluminum or the like is provided on the back electrode 13 side of the solar cells in Embodiments 11 to 14 with an electric insulation layer 15 (thin film layer made of synthetic resin) interposed therebetween. Solar cells equipped with the filter F were prepared in the same manner as in Examples 11 to 14 except that the solar cells provided with the light reflecting layer 14 made of a metal material were used.

<Comparative Test Sample 1> Example 2 above
(See FIG. 2 (b)) On the surface of the infrared ray shielding layer 2 of the filter F formed by the method of Example 10, the depth of 2 to 4 is obtained.
The solar cell filter F of the present invention in which the antireflection layer 4 is provided by forming sawtooth-shaped irregularities of about μm (see FIG. 3B).
Was stacked on the surface of the transparent support substrate 11 of the solar cell (see FIG. 5) provided with the light reflection layer 14, and the periphery of the stack was fixed with an adhesive to prepare a solar cell sample 1 with a filter. .

<Comparative Test Sample 2> Example 2 above
For the solar cell of the present invention prepared in the same manner as the filter F used in the above-mentioned solar cell sample 1 except that the infrared shielding layer 2 of the filter F prepared by (see FIG. 2B) is formed by the sputtering method. Filter F
(See FIG. 3 (b))
A solar cell sample 2 with a filter was prepared by stacking the surface of the transparent supporting substrate 11 of the solar cell (see FIG. 5) provided with the light reflecting layer 14 and fixing the periphery of the stack with an adhesive.

<Comparative Test Sample 3> The solar cell in which the solar cell filter F of the present invention is not superposed on the surface of the transparent supporting substrate 11 of the solar cell (see FIG. 5) provided with the light reflecting layer 14. Was used as a solar cell sample 3.

<Comparative Test> The above-mentioned solar cell sample 1 and the sample 2 and the solar cell sample 3 not using the filter prepared by using the filter of the present invention were left outdoors to raise the cell body by sunlight. Table 2 below shows the results of measuring the temperature state (change in battery body temperature over time) and the power conversion efficiency at that time.

[0064]

[Table 2]

<Comparison Results> As shown in Table 2, solar cell samples 1 and 2 using the solar cell filter of the present invention.
The temperature of 26 ° C., which was 0 minutes after the start of standing, increased to around 50 ° C. after 20 minutes, but stabilized at about 55 ° C. after 120 minutes.

On the other hand, in the solar cell sample 3 which does not use the filter, the temperature of 26 ° C. is 2 minutes when the temperature at the start of standing is 0 minutes.
After 0 minutes, the temperature rose to around 60 ° C, and after 120 minutes, the temperature rose to around 70 ° C.

Therefore, the solar cell filter of the present invention has the effect of suppressing the temperature rising rate and the effect of lowering the temperature rising.

Further, as shown in Table 2, the solar cell samples 1 and 2 using the solar cell filter of the present invention,
Compared with Sample 3, there is an effect of improving power conversion efficiency by 1% or more.

[0069]

Since the solar cell filter of the present invention is provided with an infrared ray shielding layer, it is installed on the light incident side of the solar cell to block heat rays, which is one of the causes of the reduction in the power generation efficiency of the solar cell. It is possible to improve the power generation efficiency (conversion efficiency).

Further, by providing an ultraviolet ray shielding layer, it is possible to prevent yellowing or darkening of the battery electrode thin film structure portion such as the surface electrode (transparent electrode) of the solar cell main body or the semiconductor portion due to the ultraviolet ray, and to prevent the generation of light rays for power generation. It is possible to suppress the decrease in gain and the deterioration rate of the solar cell body.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the wavelength of light received by a general solar cell and the power generation output.

2 (a) to (f) are side sectional views for explaining various laminated structures of the filter for a solar cell of the present invention.

3 (a) to 3 (c) are side cross-sectional views illustrating a solar cell filter of the present invention having an antireflection layer provided on the surface thereof.

FIG. 4 is a partial side cross-sectional view illustrating a state in which the solar cell filter of the present invention is attached to a solar cell.

FIG. 5 is a partial side cross-sectional view illustrating a state in which the solar cell filter of the present invention is attached to a solar cell having a reflective layer.

FIG. 6 is a partial side sectional view illustrating a general solar cell.

FIG. 7 shows a relationship between a standard short-circuit current value Isc (unit: A), an open circuit voltage value Voc (unit: V), and a relative output value Wrc (unit: W) with respect to temperature in a general solar cell. It is a graph.

[Explanation of symbols]

P ... p-type semiconductor N ... n-type semiconductor PN ... semiconductor light receiving part (pn junction type semiconductor) L ... incident light ray 1 ... base material layer 2 ... infrared shielding layer 3 ... ultraviolet shielding layer 4
... Antireflection layer 11 ... Transparent support substrate 12 ... Front surface electrode 13 ... Back surface electrode 14 ... Reflection layer 15 ... Insulation layer

Claims (12)

[Claims] 1. An infrared ray L1 having a wavelength region of at least 1200 to 3000 nm on one side or both sides of the transparent substrate layer 1.
(1200 <L1 <3000 nm or 1200 ≦ L
A solar cell filter comprising an infrared shielding layer 2 formed of a transmission wavelength selective agent that shields 1 ≦ 3000 nm). 2. An infrared ray L1 having a wavelength region of at least 1200 to 3000 nm on one or both sides of the transparent substrate layer 1.
(1200 <L1 <3000 nm or 1200 ≦ L
Infrared ray shielding layer 2 formed of a transmission wavelength selection agent that shields 1 ≤ 3000 nm) and a transmission wavelength selection agent that shields ultraviolet rays L2 (L2 <400 nm or L2 ≤ 400 nm) in a wavelength region of at least 400 nm. A filter for a solar cell, which is provided with each of the ultraviolet shielding layers 3. 3. At least 1200 to 3 in the transparent substrate layer 1.
Infrared ray L1 in the wavelength region of 000 nm (1200 <L1 <
3000nm or 1200≤L1≤3000nm)
A filter for a solar cell, characterized in that a transmission wavelength selection agent for shielding the light is kneaded. 4. At least 1200 to 3 in the transparent substrate layer 1.
Infrared ray L1 in the wavelength region of 000 nm (1200 <L1 <
3000nm or 1200≤L1≤3000nm)
And a transmission wavelength selection agent that blocks at least ultraviolet rays L2 (L2 <400 nm or L2 ≤ 400 nm) in a wavelength region smaller than 400 nm are kneaded. 5. The antireflection layer 4 is provided on the outermost layer of the transparent base material layer 1, the infrared shielding layer 2 and the ultraviolet shielding layer 3 of the filter. Filter for solar cells. 6. The transmission wavelength selective agent for shielding infrared rays L1 is made of a metal oxide such as tin oxide, zinc oxide or magnesium oxide, or an inorganic substance such as gold, silver or a mixture of any two or more thereof. The solar cell filter according to claim 1, which comprises a main component. 7. The inorganic compound as a main component, wherein the transmission wavelength selective agent for blocking ultraviolet rays L2 is zinc oxide, cerium oxide, titanium oxide, or a mixture of any two or more thereof. Item 4. A solar cell filter according to item 4. 8. The filter for a solar cell according to claim 6 or 7, wherein the transmission wavelength selection agent is mainly composed of an ultrafine powdered inorganic material having a particle size of 500Å or less. 9. A solar cell provided with a semiconductor light receiving section for converting incident light rays into electric energy on a transparent supporting substrate, which is provided on the front surface or the back surface of the supporting substrate and cuts the heat rays of the incident light rays so that the sun Claim 1 which suppresses temperature rise of a battery
A filter for a solar cell according to claim 8. 10. A transparent support substrate is provided on the surface of a surface electrode (transparent electrode) of a solar cell provided with a semiconductor light receiving section for converting incident light rays into electric energy, and cuts heat rays of the incident light rays. The solar cell filter according to claim 1, wherein the temperature rise of the solar cell is suppressed. 11. A surface electrode (transparent electrode) of a solar cell provided with a semiconductor light receiving section for converting incident light rays into electric energy on an opaque supporting substrate, and cuts heat rays of the incident light rays. Claim 1 which suppresses temperature rise of a solar cell
A filter for a solar cell according to claim 8. 12. A transparent protective plate of a solar cell having a semiconductor light receiving section for converting incident light rays into electric energy on an opaque support substrate, and is provided on the front surface or the back surface of the transparent protection plate to cut heat rays of the incident light rays. The solar cell filter according to claim 1, wherein the temperature rise of the solar cell is suppressed.