JP6008184B2 - Solar cell - Google Patents

Description

  The present invention relates to a solar cell using an organic material.

  Solar cells occupy an important position in clean energy. FIG. 4 is a cross-sectional view schematically showing a solar cell using a conventional inorganic semiconductor. In a conventional solar cell 40, a P layer 42 a and an N layer 42 b are joined in order as a power generation body 42 on an aluminum electrode 41, a transparent electrode 43 is provided on the power generation body 42, and a glass substrate or film is formed on the transparent electrode 43. A material 44 is provided. A transparent resin such as PET is used as the film material 44, and sunlight incident from the upper surface of the glass substrate or the film material 44 passes through the transparent electrode 43 such as ITO, and an electromotive force is generated by the power generator 42.

  On the other hand, in recent years, solar cells using organic semiconductors without using inorganic semiconductors have been actively developed. FIG. 5 is a cross-sectional view schematically showing the structure of a conventional solar cell using an organic semiconductor. In the solar cell 50 using an organic semiconductor, the organic semiconductor 54 is sealed between the aluminum electrode 51 and the transparent electrode 53 formed on the glass substrate 52, and is formed on the outer periphery between the aluminum electrode 51 and the transparent electrode 53. A sealing material 55 is provided.

  By the way, the importance of the development of the solar cell is recognized again because it uses natural energy. For example, in Patent Document 1, a non-woven fabric made of carbon fiber is impregnated with a phenol resin, cured, and carbonized. The carbon composite material is immersed in a silicon melt in the carbon composite material to form a composite substrate of carbon and silicon, and this composite material substrate is used as a solar cell substrate.

  In Patent Document 2, carbon nanotubes are dispersed in pulp fibers as a paper raw material to form carbon nanotube composite paper, the composite paper is impregnated with a sensitizing dye and an electrolytic solution, and lead wires are connected to both sides of the composite paper, A dye-sensitized solar cell has been obtained.

  Patent Document 3 discloses an ionic liquid gel electrolyte by gelling a liquid electrolyte with a gelling agent composed of an oligomer. Using this, a gelled electrolyte cell is prepared, and a dye-sensitized photoelectric conversion element is obtained. Forming.

JP 2000-106446 A (for example, paragraphs 0021 to 0024) JP 2011-241499 A (front page) Japanese Patent No. 4811642 (for example, paragraphs 0041-0043)

  In the inorganic semiconductor solar cell shown in FIG. 4, since a relatively strong inorganic material such as Si is sandwiched between the upper and lower electrodes 41 and 43, the distance between the electrode 41 and the electrode 43 is easily kept constant. However, in the solar cell of the organic semiconductor 54 shown in FIG. 5, if the solar cell 50 itself is bent due to the position of the organic semiconductor 54 sandwiched between the upper and lower electrodes 51, 53, the strength of each part of the organic semiconductor 54 increases. A difference occurs, and the distance between the upper and lower electrodes 51 and 53 is not kept constant, and varies depending on the location. Thereby, the subject that the electromotive force of the solar cell 50 cannot be kept constant occurs.

  In view of the above, an object of the present invention is to provide a solar cell that can keep the distance between electrodes constant even if it is bent or bent in a solar cell using an organic material.

In order to achieve the above object, a solar cell of the present invention includes a porous sheet impregnated with a power generation material containing an organic material, and electrodes provided on upper and lower surfaces of the porous sheet impregnated with the power generation material. It includes, Ru porous sheet is paper, foreign paper, pulp fibers, der either chemical fiber.
In the above structure, the electrode is made of a transparent metal film or made of a resin in which metal powder and conductive nanomaterial are dispersed.

The said structure WHEREIN: The distance between electrodes is kept constant because a porous sheet has fixed thickness.

  According to the present invention, a porous sheet having a constant thickness regardless of whether it is curved or bent is impregnated with an organic material as a power generation material, and the interval between the upper surface and the lower surface of the porous sheet is constant. The distance between the electrodes provided above and below the quality sheet is constant. Therefore, even if an electromotive force is generated at both ends of the organic material due to light irradiation, the output can be kept constant.

It is sectional drawing which shows typically the solar cell which concerns on embodiment of this invention. It is sectional drawing which shows typically the solar cell different from FIG. It is process drawing which shows typically the manufacturing method of the solar cell which concerns on embodiment of this invention. It is sectional drawing which shows typically the solar cell using the conventional inorganic semiconductor. It is sectional drawing which shows typically the structure of the solar cell using the conventional organic semiconductor.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view schematically showing a solar cell according to an embodiment of the present invention. As shown in FIG. 1, a solar cell 10 according to an embodiment of the present invention includes a porous sheet 11 impregnated with a power generation material, and electrodes 12 provided on the upper and lower surfaces of the porous sheet 11 impregnated with the power generation material. 13 and surface protective layers 14 and 15 provided on the upper and lower surfaces of the electrodes 12 and 13.

  The porous sheet 11 only needs to be able to absorb a power generation material including an organic material. For example, Japanese paper, western paper, pulp fiber, chemical fiber, or the like is used. The porous sheet 11 only needs to have a certain thickness. The porous sheet 11 is impregnated with a power generation material, and electrodes 12 and 13 are provided on the upper and lower surfaces of the porous sheet 11. By doing in this way, even if the solar cell 10 is bent or curved, the distance between the electrodes 12 and 13 does not change. Since the distance between the electrodes does not change, the output of the solar cell 10 can be made constant.

  The porous sheet 11 is preferably black or translucent. This is because black is a light-absorbing color, so that it is difficult for light rays to be reflected. The porous sheet 11 only needs to be able to be energized in a state where the material of the power generation material is immersed. The porous sheet 11 is preferably thin, and for example, a fiber material such as Japanese paper, chemical fiber, and pulp fiber having a thickness of 10 to 30 μm can be used.

  The power generation material impregnated in the porous sheet 11 is formed by dispersing an electron acceptor and an electron supply body with a conductive polymer. As the electron acceptor, for example, triphenylene, benzophenone, or the like can be used. As the electron supplier, for example, tetracyanoquinodimethane, tetracyanoethylene, or the like can be used. As the conductive polymer, for example, polythiophene, polyethylenedioxymethylene, or the like can be used.

  As the electrodes 12 and 13, transparent electrodes such as ITO and ZnO can be used, and conductive materials such as Ag, Au and C, and nanostructures such as conductive nanowires are dispersed in a resin such as PET and glass fiber. Can be used. Dispersing nanostructures such as conductive nanowires not only provides electrical conductivity, but the nanostructures adhere to the power generation material and porous sheet, causing the power generation material and porous sheet to peel off from the electrode. It becomes difficult. This is because the surface of the electrode becomes uneven due to the nanowire, and the contact area with the power generation material increases. Further, since the surfaces of the electrodes 12 and 13 have irregularities, the adhesion with the power generation material is improved.

  Surface protective layers 14 and 15 are provided outside the electrodes 12 and 13, respectively. As the surface protective layers 14 and 15, a light-transmitting sheet or film is used. The surface protective layers 14 and 15 are made of an insulating polymer material such as PET, for example.

  As shown in FIG. 3, lead wires 16 and 17 are connected to the upper and lower electrodes 12 and 13, respectively, and an electromotive force from the solar cell can be output to the outside.

  As shown in FIG. 1, electrodes 12 and 13 are provided above and below a porous sheet 11 impregnated with a power generation material. In order to insulate the electrode 12 and the electrode 13 from the outer peripheral edge of the porous sheet 11. Insulating material 18 such as resin is interposed. By providing the insulating material 18, the thickness of the porous sheet 11 can be managed up to the terminal outer peripheral portion which is the outer peripheral edge portion of the solar cell, and a wider area can be obtained. The thickness t1 of the porous sheet 11, the thickness t2 of the electrodes 12 and 13, and the thickness t3 of the surface protective layers 14 and 15 can be appropriately set according to the application and purpose. For example, the thickness t1 of the porous sheet 11 is 0.03 to 0.07 mm, the thickness t2 of the electrodes 12 and 13 is 0.01 to 0.03 μm, and the thickness t4 of the surface protective layers 13 and 14 is 0. 0.05 to 0.1 mm.

  FIG. 2 is a cross-sectional view schematically showing a solar cell different from FIG. Also in the solar cell shown in FIG. 2, electrodes 22 and 23 are provided above and below the porous sheet 21 impregnated with the power generation material, but unlike FIG. 1, the electrodes 22 and 23 are provided on the outer peripheral edge of the porous sheet 21. 23 is not provided.

  In the form shown in FIG. 2, the outer peripheral edge portions 24 a and 25 a of the surface protective layers 24 and 25 provided outside the electrodes 22 and 23 are in close contact with each other to seal the porous sheet 21. Also in this embodiment, the porous sheet 21 is impregnated with the power generation material, and the electrodes 22 and 23 are provided on the upper and lower surfaces of the porous sheet 21. However, even if the solar cell 20 is bent or curved, the electrodes 22 and 23 are provided. The distance between them does not change. Therefore, the output of the solar cell 20 can be kept constant. In the form shown in FIG. 2, in order to directly seal the outer peripheral edge portions 24 a and 25 a of the surface protective layers 24 and 25, the upper and lower electrodes 22 and 23 are set in a range slightly inside the outer periphery of the sealing portion, A power generation area in a range in which the porous sheet 11 has a uniform thickness is obtained. In such a configuration, the component configuration can be simplified by directly welding or adhering the upper and lower surface protective layers 24 and 25.

  Next, the manufacturing method of the solar cells 10 and 20 shown in FIG.1 and FIG.2 is demonstrated. FIG. 3 is a process diagram schematically showing a method for manufacturing a solar cell according to an embodiment of the present invention.

  First, each organic semiconductor of an electron supply body and an electron acceptor and a conductive polymer are mixed to form a gel-like or liquid mixed liquid 31, and a porous sheet 32 is immersed in the mixture. After impregnation, the porous sheet 31 is immersed. Is pulled up vertically as shown in FIG. Thereafter, the organic semiconductor and the conductive polymer laminated on the porous sheet 31 are solidified and formed into a film or semi-solidified. Thus, the thickness of both surfaces of the porous sheet 33 impregnated with the conductive material can be made constant.

  Thereafter, the porous sheet 33 impregnated with the power generation material is sandwiched from both sides by sheets or films 34 and 35 having a conductive film. Thereby, the organic material hold | maintained at the porous sheet and the electroconductive film adhere. At this time, the lead wires 16 and 17 may be connected to the conductive film for external extraction. In particular, when a conductive film in which a conductive material or a nanostructure is dispersed in a resin is used as the conductive film, the resin and the organic material are bonded by intermolecular force.

  In the solar cells 10 and 20 according to the embodiment of the present invention, the power generation material is held by the porous sheets 11 and 21 and the thickness of the porous sheets 11 and 21 is made uniform. The distance between the electrodes 12, 13, 22, 23 can be kept constant. Such solar cells 10 and 20 have flexibility, and even if the solar cells 10 and 20 are bent, the space between the electrodes 12 and 22 and the electrodes 13 and 23 can be kept constant. The output of the batteries 10 and 20 can be kept constant.

DESCRIPTION OF SYMBOLS 10,20: Solar cell 11,21: Porous sheet 12,13,22,23: Electrode 14,15,24,25: Surface protective layer 16,17: Lead wire 31: Liquid mixture 32: Porous sheet 33: Porous sheet containing power generation material 34, 35: Sheet or film having conductive film

Claims (3)

A porous sheet impregnated with a power generation material containing an organic material;
Electrodes provided on the upper and lower surfaces of the porous sheet impregnated with the power generation material;
With
A solar cell, wherein the porous sheet is one of Japanese paper, western paper, pulp fiber, and chemical fiber.   The solar cell according to claim 1, wherein the electrode is made of a transparent metal film, or made of a resin in which a metal powder and a conductive nanomaterial are dispersed. The solar cell according to claim 1 or 2 , wherein the distance between the electrodes is kept constant by the porous sheet having a constant thickness.

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