JPH10131409A - Solar cell tile and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make any possible crack hard to get into a tile base material, besides being lighter in weight by setting up a solar cell in a tile forming type recess, and pouring dense layer forming slurry in the circumference, the low specific gravity layer forming slurry and further the said dense layer forming slurry likewise, and hardening those of slurry integrally en bloc. SOLUTION: A tile forming mold 5 is installed in a mold form 3. Then a solar cell 11 is set up in a nearly central part of a recess of this tile forming mold 5 after getting the surface turned down. Next, dense layer forming slurry is poured in and around a surface side half part or a side face of the solar cell 11, forming a surface dense forming layer 121'. In succession, low specific gravity layer forming slurry is poured in the circumference and on the backside of the surface side half part of the solar cell 11, forming a low specific gravity forming layer 122'. In addition, the dense layer forming slurry is poured on the top, forming a backside dense layer forming layer 123', and it is covered with a male mold 4. Finally they are subjected to heat treatment in which these forming layers 121', 123' and 122' are integrally hardened, forming a tile base material. With this constitution, it is able to have excellent appearance for a long period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell tile and a method for manufacturing the same.

[0002]

2. Description of the Related Art The roof tiles of a sunny house are one of the advantageous places for installing solar cells. However, the roof tile of a house is usually laid on a sloping roof, so the surface is sloping. To install a solar cell thereon, fix it with a suitable fixing member so as not to fall. There is a need. Accordingly, there is a problem that a fixing member as a separate member is required and the fixing operation is complicated.

[0003] In view of this point, various proposals have conventionally been made in which a solar cell is directly attached to a roof tile. For example, Japanese Patent Application Laid-Open No. 3-25146 proposes a glass roof tile in which a solar cell is integrally provided on the lower surface of the front part of the roof tile. However, the roof tile becomes expensive and is heavy and damaged. There is a drawback that it is easy to do.

Further, Japanese Utility Model Laid-Open No. 4-28524 proposes a solar cell element housed in a concave portion on the surface of a thick tile made of fiber reinforced cement or fired clay and fixed with an adhesive. In the official gazette of Japanese Utility Model Application Publication No.
There has been proposed a roof tile body in which a solar cell and a transparent protective plate are fitted in a storage section provided in the main body.

[0005] However, on a sunny roof,
Over time, the adhesive deteriorates, and the transparent protective plate is likely to be warped and come off, resulting in a poor appearance,
In severe cases, there is a problem that the solar cell element is dangerously dropped by the wind and rain.

On the other hand, as raw materials for building materials having excellent mechanical strength, curable inorganic compositions containing SiO ₂ 2Al ₂ O ₃ powder and alkali metal silicate as main components are known. In Japanese Patent Publication No. 3-9060, there is proposed a hydrous inorganic molding material in which ash or calcined bauxite of electric dust is mixed with an alkali metal silicate aqueous solution.

[0007]

However, when a roof tile in which a solar cell is embedded is formed by casting using this water-containing inorganic molding material, the curing shrinkage of the roof substrate portion after molding is large. Therefore, there is a problem that a crack is caused.

[0008] The present invention is lightweight, has less cracks in the tile substrate, and has an excellent appearance over a long period of time.
An object of the present invention is to provide a solar cell tile on which a solar cell is fixed and a method for manufacturing the same.

[0009]

Means for Solving the Problems The present invention described in claim 1 of the present application (hereinafter referred to as the present invention 1 when referring only to the present invention) is a solar cell tile in which a solar cell is fixed to a tile base material. A method of manufacturing, comprising: a step of installing a solar cell with its surface facing downward in a concave portion of a tile forming die having a concave portion for forming a solar cell tile to be formed; and A step of pouring a dense layer forming slurry composed of SiO ₂ ─Al ₂ O ₃ -based powder, alkali metal silicate and water at least around the surface side to form a dense layer forming layer; On the back side of the solar cell, SiO ₂ ─Al ₂ O
Pouring a slurry for forming a low specific gravity layer composed of ₃ series powder, alkali metal silicate, water and lightweight aggregate to form a low specific gravity layer forming layer, and forming the dense layer on the low specific gravity layer forming layer A step of forming a dense layer forming layer by pouring a slurry for use, and a step of integrally curing the dense layer forming layer and the low specific gravity layer forming layer to form a tile base material and removing the mold. is there.

The present invention described in claim 2 of the present application (hereinafter referred to as the present invention 2 when referring only to the present invention) is a solar cell tile in which a solar cell is fixed to a tile substrate, but around at least a surface side of the side surface of the solar cell, SiO ₂ ─
Forming a dense layer formed from Al ₂ O ₃ powder, alkali metal silicate and water, and the dense layer and the back surface of the solar cell;
A low specific gravity layer forming layer formed of SiO ₂ ─Al ₂ O ₃ type powder, alkali metal silicate, water and lightweight aggregate, and the same material as the dense layer on the back surface of the low specific gravity layer forming layer This is a solar cell roof tile formed by integrally curing a molded dense layer forming layer.

In the present invention 1, the slurry for forming the dense layer is a slurry composed of SiO ₂ ─Al ₂ O ₃ powder, an alkali metal silicate and water, and the slurry for forming the low specific gravity layer is as follows. Those composed of these and at least one of a foaming agent and a foaming agent are used.
As the SiO ₂ ─Al ₂ O ₃ powder, SiO ₂ / Al
Those with ₂ O ₃ = 1/9 to 9/1 (weight ratio) are preferably used, and the total of SiO ₂ and Al ₂ O ₃ is 5
Those containing 0% by weight or more are preferably used.

Examples of such SiO ₂ ─Al ₂ O ₃ based powders include fly ash containing 400% by weight or more containing 80% by weight or more having a particle size of 10 μm or less.
An inorganic powder obtained by melting fly ash, fly ash or clay containing 80% by weight having a particle size of 10 μm or less and having a particle size of 10 μm or less and spraying it into a gas, and 0.1 to 30 kWh / kg of mechanical powder, the inorganic powder obtained by further heating the inorganic powder at 100 to 750 ° C., and 0.1 to 30 kW to the metakaolin.
Examples include inorganic powders obtained by applying mechanical energy of h / kg, one or more kinds of powders selected from ash of an electrostatic precipitator when corundum or mullite is produced, pulverized calcined bauxite, and metakaolin.

Here, fly ash refers to JIS A
More than 40% of SiO ₂ of fine ash particles collected by a dust collector from a finely pulverized combustion boiler specified in 6201,
Moisture 1% or less, specific gravity 1.95 or more, specific surface area 2,700
It should pass at least 75% of a 44 μm standard sieve of not less than cm ² / g.

As a method for obtaining fly ash from the fly ash, any conventionally known method can be adopted, for example, a classifier generally used for wet sedimentation classification, air classification, separation by specific gravity, or a jet mill It is possible by using a fine pulverizer such as a roll mill, a ball mill and the like and a continuous system of a classifier and a pulverizer. When the amount of fly ash having a particle size of 10 μm or less is less than 80% by weight, the reactivity with an aqueous alkali metal silicate solution is reduced, and there is a possibility that strength may be reduced or poor curing may occur.

Fly ash is generally black, but when it needs to be colored, it is decolorized by firing. 400 ° C
Decoloring is possible by baking at the above temperature, but 1,000 ° C
If the firing is performed at a temperature exceeding the above range, the reactivity with the aqueous solution of the alkali metal silicate decreases, so that the above-mentioned temperature range is preferable for fly ash.

As a method of spraying fly ash or a melt of clay into a gas in order to obtain the inorganic powder, a thermal spraying technique used for ceramic coating is applied. In this thermal spraying technique, the fly ash and the clay are preferably melted at a temperature of 2,000 to 16,000 ° C. and sprayed at a speed of 30 to 80 m / s. , A high energy gas spraying method, an arc spraying method and the like are employed. The specific surface area of the reactive inorganic powder obtained by the spraying technique is generally controlled to 0.1 to 60 m ² / g.

As the clay in the above, a clay containing 5 to 85% by weight of SiO _{2 and} 90 to 10% by weight of Al ₂ O ₃ as a chemical composition is used.
Mineral clay minerals such as kaolin minerals such as dickite, nacrite, and hallocite, muscovite, illite, fenjanite, chlorite, celadonite, paragonite, blamanite, montmorillonite, beidellite, nontronite, sabonite, sauconite, etc. Smectite, chlorite, pyphyllite, talc, sand shale can be used.

The mechanical energy for obtaining the inorganic powders mentioned above refers to a compressive force, a shearing force, and an impact force, which may be used alone or in combination of two or more. . Examples of the equipment for making these work include a ball mill, a vibration mill, a planetary mill, a medium stirring type mill, a roller mill, a mortar, a jet crusher, and the like.

Clay or metakaolin as a raw material for obtaining the above-mentioned inorganic powder is not particularly limited.
The thickness is preferably from 01 to 500 μm, and more preferably from 0.1 to 100 μm.

If the mechanical energy acting on the clay or metakaolin as a raw material for obtaining the inorganic powder is too small, the reactivity with the alkali metal silicate aqueous solution decreases, and if it is too large, the load on the pulverizer becomes large. In this case, wear and damage to the apparatus increase, and a problem of mixing impurities occurs. Therefore, the amount is limited to 0.1 to 30 kwh / kg, and preferably 1.0 to 26 kwh / kg.

When applying mechanical energy to clay or metakaolin, a grinding aid may be added as necessary. Grinding aids prevent the powder of clay or metakaolin from adhering or agglomerating inside the apparatus when mechanical energy is applied, and include, for example, alcohols such as methyl alcohol and ethyl alcohol; Examples thereof include alcohol amines such as ethanolamine, metal soaps such as sodium stearate and calcium stearate, and acetone vapor. These may be used alone or in combination of two or more.

The inorganic powder can be obtained by heating the inorganic powder to 100 to 750 ° C., preferably 200 to 600 ° C. It is because improvement is recognized. When the heating temperature is lower than 100 ° C., the mechanical strength of the obtained cured product is little improved. At 750 ° C., the inorganic powder is crystallized, and the reactivity to the aqueous alkali metal silicate solution is reduced. The heating time is preferably from 1 minute to 5 hours, since the shorter the heating time, the smaller the improvement in mechanical strength of the obtained cured product, and the longer the heating time, the higher the energy cost.

As the inorganic powder, Japanese Patent Publication No.
Those described in Japanese Patent No. 9060 and Japanese Patent Publication No. 4-45471 are used. Commercially available metakaoli is used as the inorganic powder.

As the alkali metal silicate, the following formula (1)
The compound represented by is preferably used. M ₂ O · nSiO ₂ (1) In the formula (1), M represents at least one metal selected from K, Na, and Li, and n represents a rational number. When the value of n is small, a cured product having a good appearance cannot be obtained, and when the value is large, gelation tends to occur. Therefore, the value of n is preferably 0.05 to 8, and more preferably 0.5 to 2.5.

The alkali metal silicate is preferably added in the form of an aqueous solution. If the concentration of the aqueous solution in this case is too low, the reactivity with the SiO ₂ ─Al ₂ O ₃ powder tends to decrease, and if the concentration is too high, an alkali metal salt is likely to be generated. % Is preferable. The alkali metal silicate may be dissolved in water as it is under pressure and heat, but the alkali metal silicate aqueous solution is heated under pressure and heat so that SiO ₂ components such as silica sand and silica stone have a predetermined value of n. May be dissolved while being added.

If the amount of the alkali metal silicate is too small, the reactivity with the SiO ₂ ─Al ₂ O ₃ powder tends to decrease, and if it is too large, the water resistance of the obtained cured product tends to decrease. It is preferably 10 to 80 parts by weight, more preferably 20 parts by weight, based on 100 parts by weight of the SiO ₂ ─Al ₂ O ₃ powder.
７０70 parts by weight.

The water may be added in a total amount as an aqueous solution of an alkali metal silicate, or may be added in the form of both an aqueous solution of an alkali metal silicate and independent water. If the amount of water added is too small, it is difficult to cure sufficiently,
If the amount is too large, the strength of the obtained cured product tends to decrease.
10 to 100 parts by weight of iO ₂ ─Al ₂ O ₃ powder
It is preferably 1,000, more preferably 10 to 750 parts by weight, particularly preferably 50 to 500 parts by weight.

The dense layer forming slurry is JIS A 11
In the slump test according to the regulations of No. 01, the value is 50 to 2
It is preferable to adjust the viscosity so as to be 50 mm, since heat treatment for forming a dense layer becomes unnecessary.

The lightweight aggregate in the slurry for forming the low specific gravity layer is not particularly limited. For example, inorganic foams such as pearlite, glass balloon, silica balloon, fly ash, shirasu foam, phenol resin, polyethylene And an organic foam such as polystyrene.

The additive amount of the lightweight aggregate is SiO ₂ ─Al ₂ O
_It is preferably 150 parts by weight or less based on 100 parts by weight of the ₃ series powder. If the amount exceeds 150 parts by weight, the strength, the surface smoothness, and the molding workability tend to be reduced.

In each of the above slurries, an inorganic filler, a reinforcing fiber, a pigment, a foaming aid and the like can be added as required.

In the present invention 1, the dense layer forming layer may be formed by pouring the dense layer forming slurry only around the surface of the side surface of the solar cell in the roof mold, or may be formed all around the side surface. A dense layer forming slurry may be poured to form a dense layer forming layer.

In the present invention 1, the slurry is, for example,
By performing the heat treatment in an atmosphere at 50 to 100 ° C., the resin can be cured to form a tile base material. The heat treatment is not particularly limited, but can be performed by, for example, an oven.

[0034]

The method for manufacturing a solar cell tile according to the first aspect of the present invention includes a step of placing a solar cell with its surface facing downward in a concave portion of a tile forming die having a concave portion for forming a solar cell tile to be formed; A dense layer forming slurry composed of SiO ₂ ─Al ₂ O ₃ powder, an alkali metal silicate and water is poured around at least the surface side of the solar cell in the mold to form a dense layer forming layer. A slurry for forming a low-specific-gravity layer composed of SiO ₂ ─Al ₂ O ₃ -based powder, alkali metal silicate, water and lightweight aggregate is poured onto the dense layer forming layer and the back surface of the solar cell; A step of forming a layer forming layer, a step of pouring the dense layer forming slurry onto the low specific gravity layer forming layer to form a dense layer forming layer, and integrally curing the dense layer forming layer and the low specific gravity layer forming layer Forming a tile substrate and removing it from the mold Thereby, a surface dense layer is formed around at least the surface side of the side surface of the solar cell, a low specific gravity layer is formed on the surface dense layer and the back surface of the solar cell, and a back surface dense layer is formed on the back surface of the low specific gravity layer, It is possible to obtain a solar cell tile in which a solar cell is fixed in a concave portion on the surface of a tile base material composed of an integrally cured surface dense layer and a low specific gravity layer.

In the solar cell tile according to the second aspect of the present invention, the tile base is made of SiO ₂ ─A around at least the surface side of the solar cell.
a dense layer formed layer made of l ₂ O ₃ powder, alkali metal silicate and water, and S
a low specific gravity layer forming layer formed of iO ₂ ─Al ₂ O ₃ type powder, alkali metal silicate, water and lightweight aggregate, and the same material as the dense layer on the back surface of the low specific gravity layer forming layer Since the molded dense layer forming layer is made of one that is integrally cured, there is a low specific gravity layer, so it is lightweight, and the low specific gravity layer absorbs the shrinkage force of the surface dense layer, so cracks enter the tile base material It has a good appearance over a long period of time, and can maintain a state in which the solar cell is fixed.

[0036]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 to FIG. 4 are explanatory diagrams for sequentially explaining manufacturing steps of an example of a method for manufacturing a solar cell tile according to the present invention. First, in the first step, as shown in FIG. The tile mold 5 has a concave portion 51 for forming a solar cell tile to be molded.

Reference numeral 11 denotes a solar cell, which is a plate-like body having an outer shape smaller than the inner shape of the concave portion 51 of the roof mold 5.
At approximately the center of the concave portion 51 of the tile forming mold 5, the solar cell 11 is placed with its surface facing downward.

Next, in the second step, as shown in FIG. 2, a slurry for forming a dense layer is poured around the side surface of the solar cell 11 in the roof mold 5 and around the half of the surface side. The formation layer 121 'is formed.

In the third step, as shown in FIG. 3, a slurry for forming a low specific gravity layer is formed on the surface dense layer forming layer 121 ′, on the side of the solar cell 11, around the half of the front side, and on the back side. It is poured to form a low specific gravity layer forming layer 122 '.

In the fourth step, as shown in FIG. 4, on the low specific gravity layer forming layer 122 ', a dense layer comprising SiO ₂ ─Al ₂ O ₃ based powder, alkali metal silicate and water is formed. Is poured to form a back surface dense layer forming layer 123 '. The upper mold 4 is put on the mold 3.

In the final step, the mold 3 is placed in an oven (not shown) while the upper mold 4 is placed on the mold 3 and heat-treated.
Dense layer forming layers 121 ', 123' and low specific gravity layer forming layer 1
22 'is integrally cured to form a tile base material. The tile substrate to be formed has a dense layer forming layer 121 ′ formed of SiO ₂ ─Al ₂ O ₃ -based powder, an alkali metal silicate and water, at least around the surface of the side surface of the solar cell 11. On the dense layer forming layer and the back surface of the solar cell, a low specific gravity layer forming layer 122 ′ formed of SiO ₂ ─Al ₂ O ₃ -based powder, alkali metal silicate, water and lightweight aggregate, Layer forming layer 1
The dense layer 121 'and the dense layer forming layer 123' formed from the same material are integrally cured on the back surface of 22 '.

By removing the mold, as shown in FIG. 5 or FIG. 6, a dense surface layer 121 is formed around the surface side portion of the solar cell 11, and the back surface of the dense surface layer 121 and the solar cell 11 The low specific gravity layer 122 is formed on the back surface side portion and the back surface of the side surface of the lower surface, and the back surface dense layer 123 is formed on the back surface of the low specific gravity layer 122 so that the surface dense layer 121 and the low specific gravity layer 122 which are integrally cured are formed. And the back dense layer 123
The solar cell tile 1 in which the solar cell 11 is fixed in the concave portion on the surface of the tile base material 12 made of is obtained.

[0043]

The present invention will be described below with reference to examples. Examples 1 to 3 (1) Preparation of SiO ₂ ─Al ₂ O ₃ -based powder Fly ash (manufactured by Kanden Kako, average particle size 20 μm: J
ISA 6201) by a spherometer (Model: TC15, manufactured by Nisshin Engineering Co., Ltd.) to give a particle size of 1.
SiO ₂ ─A containing 100% by weight of powder of 0 μm or less
l ₂ O ₃ powder was prepared.

(2) Preparation of Aqueous Solution of Alkali Metal Silicate An aqueous solution of alkali metal silicate shown in Table 1 was prepared using 1K aqueous solution of potassium silicate (manufactured by Nippon Chemical Industry Co., Ltd.) and water.

[0045]

[Table 1]

(3) Lightweight Aggregate No. 4 perlite (made by Asano Perlite) was used as the lightweight aggregate.

(4) Preparation of Slurry Slurry for forming a dense layer Using an omni mixer (manufactured by Chiyoda Giken Kogyo Co., Ltd.), Table 2 was prepared.
After adding the SiO ₂ ─Al ₂ O ₃ -based powder, the aqueous solution of an alkali metal silicate and water in the amounts shown in
Each dense layer forming slurry was prepared.

Preparation of Slurry for Forming Low Specific Gravity Layer Using an omni mixer (manufactured by Chiyoda Giken Kogyo Co., Ltd.),
After adding the SiO ₂ ─Al ₂ O ₃ -based powder, the aqueous solution of an alkali metal silicate and water in the amounts shown in
Each dense layer forming slurry was prepared.

(5) Fabrication of Solar Cell Roof 1 The solar cell 1 installed in the roof mold 5 according to the first to final manufacturing steps described with reference to FIGS.
After each slurry is poured around the tile 1, the respective layers are integrally cured, and as shown in FIG. 5, the tile substrate 12 composed of the integrally cured surface dense layer 121, low specific gravity layer 122, and back dense layer 123. The solar cell roof tile 1 in which the solar cell 11 was fixed in the concave portion on the surface of was manufactured.

(6) Evaluation of solar cell roof tile Bending strength This was described with reference to FIGS. 1 to 4 without installing a solar cell in a rubber mold having a concave portion of 150 mm long × 50 mm wide × 10 mm high. Each slurry is poured according to the manufacturing process of the first step to the final step, and the tile substrate 12 composed of the surface dense layer 121, the low specific gravity layer 122, and the back surface dense layer 123, which are integrally cured, is 150 mm long × 50 mm wide. × A test piece having a height of 10 mm was obtained, and its bending strength was measured by a three-point bending test method using an autograph according to JIS A 5423.

Evaluation of appearance after molding The surface of the obtained solar cell tile was observed for occurrence of cracks.な い indicates that no crack occurred, and X indicates that it did. Evaluation of appearance after drying The obtained solar cell roof tile was subjected to a drying treatment at 50 ° C. for 24 hours to observe the occurrence of cracks on the surface.な い indicates that no crack occurred, and X indicates that it did. Table 2 shows the evaluation results.

[0052]

[Table 2]

Comparative Examples 1 to 3 Solar cell tiles were obtained in the same manner as in Examples 1 to 3, except that only the slurry for forming a dense layer having the amount shown in Table 3 was used. Table 3 also shows the same evaluation results as in Examples 1 to 3.

[0054]

[Table 3]

[0055]

The method for manufacturing a solar cell tile according to the first aspect of the present invention is lightweight as described above, is hard to crack in the tile base, has an excellent appearance for a long time,
A solar cell tile on which the solar cell tile is fixed can be manufactured.

The solar cell tile according to the second aspect of the present invention is lightweight as described above, is hardly cracked in the tile base material, and has an excellent appearance for a long time.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a first step of an example of a method for manufacturing a solar cell tile according to the present invention.

FIG. 2 is a cross-sectional view illustrating a second step of the example of the method for manufacturing a solar cell tile according to the present invention.

FIG. 3 is a cross-sectional view illustrating a third step of the example of the method for manufacturing a solar cell tile according to the present invention.

FIG. 4 is a cross-sectional view illustrating a fourth step of the example of the method for manufacturing a solar cell tile according to the present invention.

FIG. 5 is a cross-sectional view showing an example of a solar cell tile obtained by the method for manufacturing a solar cell tile of the present invention.

FIG. 6 is a cross-sectional view showing another example of a solar cell tile obtained by the method for manufacturing a solar cell tile of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 solar cell tile 3 mold frame 4 upper mold 5 tile mold 11 solar cell 12 tile base 12 ′ tile base forming layer 51 recess 121, 123 dense layer 122 low specific gravity layer 121 ′, 123 ′ dense layer forming layer 122 ′ Low specific gravity layer forming layer

Claims (2)

[Claims] 1. A method of manufacturing a solar cell tile in which a solar cell is fixed to a tile base material, wherein a solar cell is provided with a surface in a roof-forming-type recess having a recess for forming a solar cell tile to be formed. And turning at least around the surface of the side surface of the solar cell in the roof mold into SiO ₂ ─Al ₂ O.
A step of pouring a dense layer forming slurry composed of the ₃ series powder, alkali metal silicate and water to form a dense layer forming layer, and forming a SiO ₂ layer on the dense layer forming layer and the back surface of the solar cell.
Pouring a slurry for forming a low specific gravity layer comprising an Al ₂ O ₃ system powder, an alkali metal silicate, water and a lightweight aggregate to form a low specific gravity layer forming layer; and forming the low specific gravity layer forming layer on the low specific gravity layer forming layer. A step of pouring a slurry for forming a dense layer to form a dense layer forming layer, and a step of integrally curing the dense layer forming layer and the low specific gravity layer forming layer to form a tile base material and removing the mold. Of manufacturing solar cell tiles. 2. A solar cell tile in which a solar cell is fixed to a tile base material, wherein the tile base material has a SiO ₂ ─Al ₂ O ₃ powder at least around a surface of a side surface of the solar cell. Dense layer formed layer of aluminum, alkali metal silicate, and water, and the dense layer and the back surface of the solar cell, SiO ₂ ─Al ₂ O ₃ system powder, alkali metal silicate, water, and lightweight aggregate A solar cell comprising: a formed low specific gravity layer forming layer; and a dense layer forming layer molded from the same material as the dense layer on the back surface of the low specific gravity layer forming layer. tile.