JPWO2020050239A1 - Solar cell module and solar cell module with protective layer - Google Patents

Abstract

The solar cell module (10) of the present invention is filled between a photoelectrode (41) and a counter electrode (42) whose surfaces face each other at intervals, and between the photoelectrode (41) and the counter electrode (42). A sealing material (46) that seals the electrolytic solution (14) between the electrolytic solution (14) and the light electrode (41) and the counter electrode (42) to form a power generation unit (44), and light. The take-out electrode part (71) provided on the electrode (41) or the counter electrode (42) and electrically connected to the power generation part (44), and the take-out electrode part (71) electrically connected to the take-out electrode part (71). It includes an extension electrode film (72) that extends from 71) and is arranged so as to cover at least one portion of the back surface of the counter electrode (42).

Description

The present invention relates to a solar cell module and a solar cell module with a protective layer.
The present application claims priority based on Japanese Patent Application No. 2018-164576 filed in Japan on September 3, 2018, the contents of which are incorporated herein by reference.

Conventionally, the solar cell module described in Patent Document 1 below has been known. This solar cell module includes a first electrode, a second electrode, an electrolytic solution, a sealing material, a conductive material, and an insulating line. A transparent conductive film is formed on the surface of the first base material of the first electrode. On the surface of the transparent conductive film, a plurality of band-shaped semiconductor layers on which the dye extending in the first direction is adsorbed are formed. A counter conductive film is formed on the surface of the second base material so as to face the first electrode. The electrolytic solution is sealed between the semiconductor layer of the first electrode and the second electrode. The sealing material seals the electrolytic solution. The encapsulant arranges a plurality of cells divided in a second direction orthogonal to the first direction in a plan view. The conductive material is provided so as to be covered with a sealing material. The insulation line extends along the second direction with respect to the first and second electrodes. A plurality of cells arranged in the second direction are electrically connected by series wiring. A conductive material is arranged between the first insulating part of the first base material and the second insulating part of the second base material arranged between the cells adjacent to each other in the second direction. As a result, the first electrode and the second electrode of adjacent cells are electrically connected to each other. As a result, adjacent cells are connected to each other.

Japanese Unexamined Patent Publication No. 2018-82137

In the conventional solar cell module, there is room for improvement in improving the amount of power generation per unit area.

The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the amount of power generation per unit area.

In order to solve the above problems, the present invention proposes the following means.
The solar cell module according to one aspect of the present invention includes a photoelectrode and a counter electrode having surfaces facing each other at intervals, an electrolytic solution filled between the photoelectrode and the counter electrode, and the photoelectrode. A sealing material that seals the electrolytic solution between the counter electrode and forms a power generation portion, and a take-out electrode portion provided on the photoelectrode or the counter electrode and electrically connected to the power generation portion. An extension electrode film that is electrically connected to the take-out electrode portion, extends from the take-out electrode portion, and is arranged so as to cover at least one portion of the back surface (the surface opposite to the optical electrode) of the counter electrode. ing.
In addition, in this specification, "electrically connecting" means physically connecting two or more members with each other via a conductive member.

Light enters the power generation unit from the back surface of the optical electrode (the surface opposite to the counter electrode), and the power generation unit generates power. The electric power generated by the power generation unit is taken out through the take-out electrode part and the extension electrode film.
The extension electrode film is a take-out electrode portion provided on the optical electrode (hereinafter, may be referred to as a “photoelectrode side take-out electrode portion”) and a take-out electrode portion provided on the counter electrode (hereinafter, ““ photoelectrode side take-out electrode portion ”). It may be provided on either one of the counter electrode side take-out electrode portion ”), but it is more preferable to provide it on both of the electrode portions. However, when the extension electrode film is provided on both the light electrode side take-out electrode portion and the counter electrode side take-out electrode portion, the extension electrode films are prevented from coming into contact with each other.

The extension electrode film extends from the take-out electrode portion to the back surface of the counter electrode instead of the back surface of the optical electrode. Therefore, for example, even if a large area of the extension electrode film is secured, there is no effect when light is incident from the back surface of the light electrode. Therefore, a large area of the extension electrode film can be secured without reducing the amount of power generation. As a result, even if the area occupied by the extraction electrode portion of the optical electrode or the counter electrode is small, the electric power generated by the power generation portion can be reliably extracted through the extension electrode film. The take-out electrode part itself does not contribute to the power generation itself by the power generation part, and the smaller the area of the take-out electrode part, the more the amount of power generation per unit area of the solar cell module can be improved. Therefore, by providing the extension electrode film and reducing the area of the take-out electrode portion as described above, it is possible to improve the amount of power generation per unit area of the solar cell module.

Moreover, by securing a large area of the extension electrode film, for example, the extension electrode film can be firmly adhered to the back surface of the counter electrode. Thereby, for example, the electrical connection between the take-out electrode portion and the extension electrode film can be stabilized, and the performance reliability of the solar cell module can be improved.

Further, by securing a large area of the extension electrode film, the back surface of the counter electrode can be protected by the extension electrode film. Thereby, for example, the durability of the solar cell module can be improved.

The optical electrode includes a transparent electrode film and a semiconductor layer on which a dye is adsorbed and laminated on the transparent electrode film. In a plan view of the optical electrode, the extended electrode film is at least one of the semiconductor layers. It may overlap in part.

In the plan view of the optical electrode, the extension electrode film overlaps at least a part of the semiconductor layer. Therefore, when the optical electrode is viewed from the back surface, the extension electrode film is arranged on the rear side of the semiconductor layer. For example, when the extension electrode film is formed of a metal foil and the extension electrode film has metallic luster, it is difficult to visually recognize scratches and color unevenness of the semiconductor layer based on the reflected light from the extension electrode film. Can be done. Although the extended electrode film does not have metallic luster, for example, when the extended electrode film is black and has a light-shielding property, or when the extended electrode film has the same color as the dye of the semiconductor layer. Similarly, it is possible to make it difficult to visually recognize scratches and color unevenness of the semiconductor layer.

Further, when the optical electrode is viewed from the back surface, the extension electrode film is commonly located on the rear side of the extraction electrode portion and the semiconductor layer, so that the background of the extraction electrode portion and the semiconductor layer can be used as a common background. can. As a result, for example, the appearance (aesthetics) of the solar cell module can be improved.

A plurality of the semiconductor layers are arranged at intervals in the first direction, the sealing material is arranged between the semiconductor layers adjacent to each other in the first direction, and the power generation unit is arranged in the first direction. The power generation units formed in plurality along the above direction and adjacent to each other in the first direction are electrically connected to each other (that is, adjacent cells are electrically connected to each other), and the take-out electrode unit is described. It may be provided at the end of the optical electrode or the counter electrode in the first direction.
In this case, when the extension electrode film is provided on both the photoelectrode side take-out electrode portion and the counter electrode side take-out electrode portion, the photoelectrode side take-out electrode portion and the counter electrode side take-out electrode portion are respectively in the first direction. It is preferably provided at the ends on different sides.

The photoelectrode and the counter electrode each include a base material and a transparent electrode film laminated on the surface of the base material, and the take-out electrode portion is the transparent electrode film of the photoelectrode or the counter electrode. The extension electrode film provided on the transparent electrode film may be extended from the take-out electrode portion to the back surface of the base material of the counter electrode.

The solar cell module with a protective layer according to one aspect of the present invention includes the solar cell module and a protective layer for protecting the solar cell module.

Further, a take-out wiring electrically connected to the extension electrode film through an opening formed in the protective layer may be provided.

The take-out wiring is connected to the extension electrode membrane. When the take-out wiring is connected to the extension electrode film by, for example, soldering, heat is applied to the extension electrode film. When the area of the extension electrode film is small, the amount of heat to be borne per unit area of the extension electrode film increases, and the heat may damage (melt) the extension electrode film, the counter electrode, and the optical electrode.

However, in this solar cell module with a protective layer, since the extension electrode film is extended to the back surface of the counter electrode as described above, a large area of the extension electrode film can be secured. As a result, even when the take-out wiring is connected to the extension electrode film by soldering, the amount of heat to be borne per unit area of the extension electrode film can be kept low. As a result, damage to the extension electrode film and the like can be suppressed.

The take-out wiring is connected to the extension electrode film through an opening formed in the protective layer. When the area of the extension electrode film is small, it becomes necessary to combine the protective layer with the solar cell module with the openings accurately aligned with the extension electrode film. That is, in this case, when the protective layer is combined with the solar cell module, if the protective layer is displaced even slightly with respect to the solar cell module, the opening is arranged on a member different from the extension electrode film, resulting in a defective product. Yield may decrease.

However, in this solar cell module with a protective layer, since the extension electrode film is extended to the back surface of the counter electrode as described above, a large area of the extension electrode film can be secured. Therefore, when the protective layer is combined with the solar cell module, the opening can be positioned on the extension electrode film even if the position of the opening is slightly deviated from the target position. As a result, the yield of the product can be improved.

According to the present invention, the amount of power generation per unit area can be improved.

It is a top view of the dye-sensitized solar cell with a protective layer which concerns on one Embodiment of this invention as seen from the counter electrode side, and is the figure which shows the state which permeated through the moisture-proof layer. It is a schematic cross-sectional view corresponding to the cross-sectional view taken along the line II-II shown in FIG. 1, and is a side view of a dye-sensitized solar cell. FIG. 5 is a plan view of the dye-sensitized solar cell constituting the dye-sensitized solar cell with a protective layer shown in FIG. 1 as viewed from the counter electrode side, and is a view showing a state in which the dye-sensitized solar cell has passed through the extension electrode film. FIG. 3 is a cross-sectional view taken along the line IV-IV shown in FIG. It is an enlarged plan view of the main part of the dye-sensitized solar cell with a protective layer shown in FIG. FIG. 5 is an enlarged plan view of a main part corresponding to FIG. 5 of a dye-sensitized solar cell with a protective layer according to a first modification of the first embodiment of the present invention. FIG. 5 is an enlarged plan view of a main part corresponding to FIG. 5 of a dye-sensitized solar cell with a protective layer according to a second modification of an embodiment of the present invention. A dye-sensitized solar cell with a protective layer according to a third modification of the embodiment of the present invention, which is a plan view corresponding to FIG. 1. It is a dye-sensitized solar cell constituting the dye-sensitized solar cell with a protective layer which concerns on the 4th modification of one Embodiment of this invention, and is the cross-sectional view which corresponds to FIG. It is a dye-sensitized solar cell constituting the dye-sensitized solar cell with a protective layer which concerns on the 5th modification of one Embodiment of this invention, and is the cross-sectional view which corresponds to FIG.

Hereinafter, the configuration of the embodiment of the solar cell module according to the present invention will be described in detail with reference to the drawings with reference to FIGS. 1 to 5 as appropriate. The materials, dimensions, etc. exemplified in the following description are examples, and the present invention is not limited thereto, and the present invention can be appropriately modified without changing the gist thereof.

In the following description, as an example of the solar cell module according to the present invention, a film-type dye-sensitized solar cell manufactured by using the roll-to-roll method will be mentioned. explain. Here, the solar cell module to which the present invention is applied is not limited to the dye-sensitized solar cell. The present invention includes all solar cell modules other than the dye-sensitized solar cell as long as the two electrodes subjected to the insulation treatment are bonded to each other with a sealing material interposed therebetween. Further, the solar cell module according to the present invention has a configuration manufactured by using the roll-to-roll method described above, that is, it is continuously manufactured while transporting a base material in a predetermined direction. It is not limited to what is done. The present invention also includes, for example, one in which a cell structure is formed for each base material cut in advance.

[Structure of solar cell module with protective layer (dye-sensitized solar cell with protective layer)]
As shown in FIGS. 1 and 2, the dye-sensitized solar cell with a protective layer (solar cell module with a protective layer) 1 of the present embodiment to which the present invention is applied is a dye-sensitized solar cell (solar cell module). A protective layer 2 for protecting the dye-sensitized solar cell 10 and a take-out wiring 3 electrically connected to an extension electrode film 72 described later through an opening 2a formed in the protective layer 2 are provided. ..
In this example, a set of extension electrode films 72 is provided, one of which is extended from the photoelectrode side take-out electrode portion and the other is extended from the counter electrode side take-out electrode portion. Both of them may be extended from the take-out electrode portion 71 on the optical electrode 41 side or the take-out electrode portion 71 on the counter electrode 42 side, or one is extended from the take-out electrode portion 71 on the light electrode 41 side and the other is. It may be extended from the take-out electrode portion 71 on the opposite electrode 42 side.

[Structure of solar cell module (dye-sensitized solar cell)]
As shown in FIGS. 3 and 4, the dye-sensitized solar cell 10 of the present embodiment to which the present invention is applied is electrically connected to the optical electrode 41, the counter electrode 42, the power generation unit 44, and the sealing material 46. It is equipped with material 48.
As shown in FIG. 4, the surfaces of the optical electrode 41 and the counter electrode 42 (surfaces facing each other) face each other with a gap. Hereinafter, the direction in which the optical electrode 41 and the counter electrode 42 face each other is referred to as a stacking direction D3 (third direction).

The photoelectrode 41 includes a photoelectrode support 21 (base material), a photoelectrode conductive layer 31 (transparent electrode film) provided on the surface 21a of the photoelectrode support 21, and a photoelectrode conductive layer 31 on which a dye is adsorbed. It has a plurality of inorganic semiconductor layers 12 (semiconductor layers) intermittently laminated on the surface.

The photoelectrode support 21 is a member that serves as a base for the photoelectrode conductive layer 31, the inorganic semiconductor layer 12, the sealing material 46, and the conductive material 48. The material of the photoelectrode support 21 is flexible enough to be applied to continuous production of solar cells using the roll-to-roll method, and can be formed into a large-area film. If so, there is no particular limitation. Examples of the material of such a light electrode support 21 include a transparent resin material such as polyethylene terephthalate (PET), acrylic, polycarbonate, polyethylene naphthalate (PEN), and polyimide.

In the plan view of the optical electrode support 21 as shown in FIG. 3, the optical electrode support 21 is formed in a rectangular shape. Hereinafter, the directions in which each side of the optical electrode support 21 extends in the plan view are referred to as a D1 direction (first direction) and a D2 direction (second direction). The D1 and D2 directions are orthogonal to each other.

As shown in FIG. 4, the optical electrode conductive layer 31 is formed over the entire surface 21a of the optical electrode support 21 (that is, the surface of the optical electrode support 21 on the counter electrode 42 side) in the D1 direction.
The photoelectrode conductive layer 31 is laminated over the entire surface of the surface 21a of the photoelectrode support 21.

Examples of the material of the photoelectrode conductive layer 31 include tin oxide (ITO) and zinc oxide.
Both the photoelectrode support 21 and the photoelectrode conductive layer 31 are transparent and transmit light incident from the back surface of the photoelectrode support 21.

The inorganic semiconductor layer 12 is formed on the surface of the photoelectrode conductive layer 31 (that is, the surface of the photoelectrode conductive layer 31 on the counter electrode 42 side). In other words, a plurality of inorganic semiconductor layers 12 are arranged at intervals in the D1 direction. Each inorganic semiconductor layer 12 is formed in a band shape extending long in the D2 direction.

The inorganic semiconductor layer 12 is, for example, a porous layer dyed by supporting a sensitizing dye on a metal oxide or the like, and has a function of receiving and transporting electrons from the sensitizing dye. Examples of such a metal oxide include titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ) and the like.

The above-mentioned sensitizing dye is composed of an organic dye or a metal complex dye. Examples of the organic pigment include various organic pigments such as coumarin-based, polyene-based, cyanine-based, hemicyanine-based, and thiophene-based. Examples of the metal complex dye include a ruthenium complex and the like.

The counter electrode 42 is provided on the counter electrode support 22 (base material) facing the photoelectrode support 21 and the surface 22a of the counter electrode support 22 (the surface of the counter electrode support 22 on the light electrode 41 side). It has a counter electrode conductive layer 32 (transparent electrode film).

The counter electrode support 22 is a member that serves as a base for the counter electrode conductive layer 32. The material of the counter electrode support 22 is flexible enough to be applied to the continuous production of solar cells using the roll-to-roll method, like the optical electrode support 21. The material is not particularly limited as long as it can be formed into a large-area film. Examples of the material of the counter electrode support 22 include the same resin material as the photoelectrode support 21.

The counter electrode conductive layer 32 is formed over the entire surface 22a of the counter electrode support 22 in the D1 direction. The counter electrode conductive layer 32 is laminated on the surface 22a of the counter electrode support 22. Examples of the material of the counter electrode conductive layer 32 include compounds similar to those of the photoelectrode conductive layer 31.

The power generation unit 44 is sandwiched between the light electrode 41 and the counter electrode 42 in the thickness direction (stacking direction D3) of the light electrode 41 and the counter electrode 42, and is in the surface direction of the light electrode 41 and the counter electrode 42 (in FIG. 4). A plurality of electrodes are provided at intervals along the D1 direction shown in (1). The power generation unit 44 includes the above-mentioned inorganic semiconductor layer 12 and a charge transfer body (electrolyte solution, electrolyte) 14.

The charge transfer body 14 is filled between the light electrode 41 and the counter electrode 42. The charge transfer body 14 is filled so as to be in contact with the inorganic semiconductor layer 12. The charge transfer body 14 is a solution in which a supporting electrolyte such as lithium iodide and iodine are mixed with a liquid component such as an ionic liquid such as acetonitrile, dimethylpropyl imidazolium iodide or butyl methyl imidazolium iodide (for example). Specific examples thereof include non-aqueous solvents such as propionitrile).

The sealing material 46 seals the charge transfer body 14 between the light electrode 41 and the counter electrode 42 to form the power generation unit 44. The sealing material 46 seals the power generation unit 44 including the charge transfer body 14 together with the sealing unit 60 shown in FIG. The sealing material 46 is provided on both sides of the power generation unit 44 along the D1 direction shown in FIGS. 3 and 4. The sealing material 46 is provided adjacent to the power generation unit 44 in the D1 direction. The sealing material 46 is arranged between the inorganic semiconductor layers 12 adjacent to each other in the D1 direction. The sealing material 46 forms a plurality of power generation units 44 along the D1 direction. A pair of sealing materials 46 are arranged between power generation units 44 adjacent to each other in the D1 direction.

The sealing material 46 further contains a resin or the like for adhering the optical electrode 41 and the counter electrode 42 to each other. Examples of the material of such a sealing material 46 include a resin material containing at least one of a thermoplastic resin, a thermosetting resin, and an ultraviolet curable resin.

A conductive material 48 is provided between the pair of sealing materials 46 arranged between the power generation units 44 adjacent to each other in the D1 direction. The conductive material 48 electrically connects the power generation units 44 including the inorganic semiconductor layer 12 and the charge transfer body 14 (that is, adjacent cells to each other) to conduct electricity. The material of the conductive material 48 is not particularly limited as long as it is a conductive material. Examples of the material include known conductive materials, conductive pastes, and mixtures of conductive fine particles and adhesives. In the illustrated example, as an example of the conductive material 48, a conductive paste in which an appropriate amount of conductive particles 36 is mixed with an adhesive 38 such as an epoxy resin or a phenol resin is used. This configuration is preferable because the conductive material 48 can be easily cut when the dye-sensitized solar cell 10 is cut out in a desired pattern. As the conductive material 48, a binder made of the same material as the sealing material 46 may be used.

The optical electrode conductive layer 31 and the counter electrode conductive layer 32 are provided with a first insulating portion 50A and a second insulating portion 50B, respectively. The first insulating portion 50A and the second insulating portion 50B are provided at a portion overlapping the sealing material 46 of the photoelectrode conductive layer 31 and the counter electrode conductive layer 32 in the cross section orthogonal to the D1 direction shown in FIG. There is. The first insulating portion 50A and the second insulating portion 50B may be hollow, and a part of the sealing material 46 may flow into the first insulating portion 50A and the second insulating portion 50B. The first insulating portion 50A and the second insulating portion 50B are provided in a long strip shape in the D2 direction in a plan view.

The light electrode conductive layer 31 of the light electrode 41 is provided with a first insulating portion 50A. A second insulating portion 50B is provided on the counter electrode conductive layer 32 of the counter electrode 42. In the example shown in FIG. 4, the first insulating portion 50A and the second insulating portion 50B penetrate the optical electrode conductive layer 31 or the counter electrode conductive layer 32 in the thickness direction. In other words, the first insulating portion 50A divides (electrically shuts off) the optical electrode conductive layer 31 in the D1 direction. The second insulating portion 50B divides (electrically shuts off) the counter electrode conductive layer 32 in the D1 direction.

As described above, the conductive material 48 electrically connects the optical electrode 41 in one cell and the counter electrode 42 in the cell adjacent to the cell in the stacking direction D3. Further, the first insulating portion 50A and the second insulating portion 50B locally insulate the optical electrode 41 and the counter electrode 42 in the D1 direction. As a result, the power generation units 44 adjacent to each other in the D1 direction are electrically connected in series with each other (that is, cells adjacent to each other are electrically connected in series).

As shown in FIG. 3, the dye-sensitized solar cell 10 is provided with a seal portion 60 (fused portion, ultrasonic fused portion). The seal portion 60 is provided at a predetermined position in the D2 direction of the dye-sensitized solar cell 10. In the seal portion 60, the optical electrode 41 and the counter electrode 42 are bonded to each other over the entire length in the D1 direction of the dye-sensitized solar cell 10.

The seal portion 60 is a portion that is electrically insulated by crimping the optical electrode support 21 and the counter electrode support 22. The photoelectrode support 21 and the counter electrode support 22 are, for example, from the outside (that is, above and below the dye-sensitized solar cell 10) in the thickness direction (stacking direction D3) of the photoelectrode 41 and the counter electrode 42. The light electrode 41 and the counter electrode 42 can be crimped by applying or pressing a force using a method such as ultrasonic fusion. The light electrode conductive layer 31, the counter electrode conductive layer 32, the inorganic semiconductor layer 12, and the charge transfer body 14 are interposed between the crimped optical electrode support 21 and the counter electrode support 22 with a small thickness. It may be. However, since each of these layers is in a state of being substantially divided at the seal portion 60, the power generation units 44 adjacent to the seal portion 60 are not electrically connected to each other.

As shown in FIG. 4, the light electrode 41 is provided with a take-out electrode portion 71. The take-out electrode unit 71 is electrically connected to the power generation unit 44. The take-out electrode unit 71 takes out the electric power generated by the power generation unit 44. In the present embodiment, the extraction electrode portion 71 is provided at the end portion of the optical electrode 41 in the D1 direction. The take-out electrode portion 71 is formed by exposing the optical electrode conductive layer 31 to the counter electrode 42 side along the stacking direction D3. In the illustrated example, the light electrode 41 is larger in the D1 direction than the counter electrode 42, and the end portion of the light electrode 41 projects in the D1 direction with respect to the counter electrode 42. As a result, the light electrode conductive layer 31 forms the take-out electrode portion 71. The take-out electrode portion 71 is longer in the D2 direction than in the D1 direction.

An extension electrode film 72 is electrically connected to the take-out electrode portion 71. The extension electrode film 72 is formed of, for example, a metal foil (for example, a copper tape having an adhesive layer formed on the surface of the copper foil). As shown in FIG. 4, the extension electrode film 72 extends from the take-out electrode portion 71 to the back surface of the counter electrode 42 (the back surface 22b of the counter electrode support 22). The extension electrode film 72 is adhered to the back surface 22b of the counter electrode support 22.

In a plan view of the optical electrode 41 as shown in FIG. 3, the extension electrode film 72 overlaps at least a part of the plurality of inorganic semiconductor layers 12. In the illustrated example, the extension electrode film 72 overlaps only the inorganic semiconductor layer 12 located at the end in the D1 direction among the plurality of inorganic semiconductor layers 12 arranged in the D1 direction. A pair of extension electrode films 72 are arranged symmetrically in the D1 direction.

The length L of one extension electrode film 72 in the D1 direction on the back surface of the counter electrode 42 (in other words, the portion of the counter electrode 42 covered by one extension electrode film 72 in the D1 direction). The length L) is, for example, 3 mm or more and 300 mm or less. The ratio L / L0 of the length L to the length L0 of the entire counter electrode 42 in the D1 direction is, for example, 0.5% or more and 49.8% or less.
Further, the length L1 in the D2 direction on the back surface of the counter electrode 42 for one extension electrode film 72 (in other words, the portion of the counter electrode 42 covered by one extension electrode film 72 in the D2 direction). The length L1) is preferably equal to, but not limited to, the length L3 of the counter electrode 42 in the D2 direction. For example, the ratio L1 / L3 of the length L1 to the length L3 in the D2 direction of the counter electrode 42 is preferably, for example, 5% or more and 100% or less, and more preferably 15% or more and 100% or less. ..
Further, when a set of extension electrode films 72 is provided as shown in FIG. 3, the ratio of the area covered by the extension electrode film 72 to the total area of the back surface of the counter electrode 42 is preferably 3% or more. It is more preferably 15% or more, and particularly preferably 50% or more. When the ratio of the area is equal to or greater than the lower limit, the amount of power generated per unit area of the dye-sensitized solar cell can be significantly improved. In addition, the performance reliability and aesthetics of the dye-sensitized solar cell can be improved. The upper limit of the area ratio is not particularly limited as long as it can prevent the extension electrode films 72 from coming into contact with each other (short circuit), and may be less than 100%, but is preferably 95% or less.
In the present invention, the occupied area of the take-out electrode portion 71 in the optical electrode and the counter electrode can be reduced. Specifically, for each of the take-out electrode portions 71 (points protruding from the photoelectrode conductive layer 31 or the counter electrode conductive layer 32 in the D1 direction), the surface area facing the opposite electrodes is 0.6 cm ² to. is preferably 40 cm ^2, more preferably from 0.6cm ² ~15cm ^2, further preferably 0.6 cm 2 2 cm ^2.

[Structure of protective layer 2]
As shown in FIGS. 1 and 2, the protective layer 2 seals the dye-sensitized solar cell 10. As shown in FIG. 2, the protective layer 2 includes a light electrode side moisture-proof film 81 and a counter electrode side moisture-proof film 82 that sandwich the dye-sensitized solar cell 10 in the stacking direction D3.

The light electrode side moisture-proof film 81 preferably has high translucency. The light electrode side moisture-proof film 81 includes a light electrode side barrier layer 83 and a light electrode side adhesive layer 84. The light electrode side barrier layer 83 may be, for example, a film having a barrier property imparted to a resin substrate.

The counter electrode side moisture-proof film 82 includes a counter electrode side barrier layer 85 and a counter electrode side adhesive layer 86. The counter electrode side barrier layer 85 may be a metal foil such as aluminum, a composite film of aluminum and polyethylene terephthalate, or the like.

As shown in FIG. 5, the opposite electrode side moisture-proof film 82 is formed with an opening 2a that exposes the extension electrode film 72 to the outside. The opening 2a has a rectangular shape extending in the D1 direction and the D2 direction in a plan view. The opening 2a is arranged at a position of the opposite electrode side moisture-proof film 82 that overlaps with the extension electrode film 72 in a plan view. The opening 2a penetrates the opposite electrode side moisture-proof film 82 in the stacking direction D3.

[Configuration of take-out wiring]
The take-out wiring 3 is connected to the extension electrode film 72 from the outside through the opening 2a. The take-out wiring 3 includes a covering portion 3a. A connecting portion 3b from which the covering portion 3a has been peeled off is formed at the tip portion of the take-out wiring 3. The connecting portion 3b is connected to the extension electrode film 72 by, for example, soldering.

As shown in FIG. 5, in the present embodiment, the take-out wiring 3 extends from the opening 2a in the D2 direction, but the present invention is not limited to this. For example, as in the dye-sensitized solar cell 1A with a protective layer of the first modification shown in FIG. 6, the take-out wiring 3 may extend from the opening 2a in the D2 direction.

As described above, according to the dye-sensitized solar cell 1 with a protective layer according to the present embodiment, the power generation unit 44 is formed from the back surface of the optical electrode 41 (the back surface 21b of the optical electrode support 21) as shown in FIG. Light is incident on the power generation unit 44 to generate electricity.
The electric power generated by the power generation unit 44 is taken out through the take-out electrode part 71 and the extension electrode film 72.

The extension electrode film 72 extends from the take-out electrode portion 71 to the back surface of the counter electrode 42 instead of the back surface of the light electrode 41. Therefore, for example, even if a large area of the extension electrode film 72 is secured, there is no effect when light is incident from the back surface of the light electrode 41. Therefore, a large area of the extension electrode film 72 can be secured without reducing the amount of power generation. As a result, even if the area occupied by the take-out electrode portion 71 of the optical electrode 41 and the counter electrode 42 is small, the electric power generated by the power generation unit 44 can be reliably taken out through the extension electrode film 72. The extraction electrode unit 71 itself does not contribute to the power generation itself by the power generation unit 44, and the smaller the area of the extraction electrode unit 71, the more the power generation amount per unit area of the dye-sensitized solar cell 10 can be improved. Therefore, by providing the extension electrode film 72 and reducing the area of the take-out electrode portion 71 as described above, it is possible to improve the amount of power generation per unit area of the dye-sensitized solar cell 10.

Moreover, by securing a large area of the extension electrode film 72, for example, the extension electrode film 72 can be firmly adhered to the back surface of the counter electrode 42. Thereby, for example, the electrical connection between the take-out electrode portion 71 and the extension electrode film 72 can be stabilized, and the performance reliability of the dye-sensitized solar cell 10 can be improved.

Further, by securing a large area of the extension electrode film 72, the back surface of the counter electrode 42 can be protected by the extension electrode film 72. Thereby, for example, the durability of the dye-sensitized solar cell 10 can be improved.

In a plan view of the optical electrode 41, the extension electrode film 72 overlaps at least a part of the plurality of inorganic semiconductor layers 12. Therefore, when the optical electrode 41 is viewed from the back surface, the extension electrode film 72 is arranged on the rear side of the inorganic semiconductor layer 12. For example, when the extension electrode film 72 is formed of a metal foil and the extension electrode film 72 has metallic luster as in the present embodiment, the inorganic semiconductor layer is based on the reflected light from the extension electrode film 72 or the like. It is possible to make it difficult to visually recognize the scratches and uneven colors of the twelve. Although the extension electrode film 72 does not have metallic luster, for example, the extension electrode film 72 has a light-shielding property such as black, or the extension electrode film 72 has the same color as the dye of the inorganic semiconductor layer 12. In such a case, it is possible to make it difficult to visually recognize the scratches and color unevenness of the inorganic semiconductor layer 12.

Further, when the optical electrode 41 is viewed from the back surface, the extension electrode film 72 is commonly located on the rear side of the take-out electrode portion 71 and the inorganic semiconductor layer 12, so that the background of the take-out electrode portion 71 and the inorganic semiconductor layer 12 Can be a common background. As a result, for example, the appearance (aesthetics) of the dye-sensitized solar cell 10 can be improved.

As shown in FIG. 1, the take-out wiring 3 is connected to the extension electrode film 72. When the take-out wiring 3 is connected to the extension electrode film 72 by solder or the like, heat is applied to the extension electrode film 72. When the area of the extension electrode film 72 is small, the amount of heat to be borne per unit area of the extension electrode film 72 increases, and the heat may damage (melt) the extension electrode film 72, the counter electrode 42, and the optical electrode 41. be.

However, in the dye-sensitized solar cell 1 with a protective layer, the extension electrode film 72 is extended to the back surface of the counter electrode 42 as described above, so that a large area of the extension electrode film 72 can be secured. As a result, even when the take-out wiring 3 is connected to the extension electrode film 72 by soldering, the amount of heat to be borne per unit area of the extension electrode film 72 can be kept low. As a result, damage to the extension electrode film 72 and the like can be suppressed.

The take-out wiring 3 is connected to the extension electrode film 72 through the opening 2a formed in the protective layer 2. When the area of the extension electrode film 72 is small, it is necessary to combine the protective layer 2 with the dye-sensitized solar cell 10 in a state where the opening 2a is accurately aligned with the extension electrode film 72. That is, in this case, when the protective layer 2 is combined with the dye-sensitized solar cell 10, if the protective layer 2 is slightly displaced with respect to the dye-sensitized solar cell 10, the opening 2a becomes different from the extension electrode film 72. If it is placed on a different member, it may become a defective product and the yield of the product may decrease.

However, in the dye-sensitized solar cell 1 with a protective layer, the extension electrode film 72 is extended to the back surface of the counter electrode 42 as described above, so that a large area of the extension electrode film 72 can be secured. Therefore, when the protective layer 2 is combined with the dye-sensitized solar cell 10, the opening 2a can be positioned on the extension electrode film 72 even if the position of the opening 2a deviates slightly from the target position. As a result, the yield of the product can be improved.

The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, as in the dye-sensitized solar cell 1B with a protective layer of the second modification shown in FIG. 7, the opening 2a may be formed in a circular shape (round shape) in a plan view. In this case, the take-out wiring 3 may extend from the opening 2a in either the D1 direction or the D2 direction.

As in the dye-sensitized solar cell 1C with a protective layer of the third modification shown in FIG. 8, the extension electrode film 72 may be arranged over the plurality of inorganic semiconductor layers 12. In the dye-sensitized solar cell 1C with a protective layer shown in FIG. 8, the extension electrode film 72 covers all the inorganic semiconductor layers 12 in the stacking direction D3.

As in the dye-sensitized solar cell 1D with a protective layer of the fourth modification shown in FIG. 9, the take-out electrode portion 71 may be provided on the counter electrode 42. In this case, the extension electrode film 72 is folded back in the stacking direction D3, and the counter electrode 42 is sandwiched in the stacking direction D3. The take-out electrode portion 71 is formed by exposing the counter electrode conductive layer 32 to the light electrode 41 side along the stacking direction D3. The extension electrode film 72 extends from the take-out electrode portion 71 to the back surface of the counter electrode 42 (the back surface 22b of the counter electrode support 22). The extension electrode film 72 is adhered to the back surface 22b of the counter electrode support 22. In this case, one of the pair of take-out electrode portions 71 may be provided on the optical electrode 41, and the remaining one may be provided on the counter electrode 42. Further, both of the pair of take-out electrode portions 71 may be provided on the counter electrode 42.

Like the dye-sensitized solar cell 1E with a protective layer of the fifth modification shown in FIG. 10, the power generation units 44 adjacent to each other in the D1 direction may be electrically connected in parallel to each other (that is, adjacent to each other). The cells to be used may be electrically connected in parallel). In the dye-sensitized solar cell 1E with a protective layer, since the insulating portions 50A and 50B are not provided, the power generation portions 44 adjacent to each other in the D1 direction are electrically connected in parallel with each other.

The dye-sensitized solar cell 10 may have a configuration (so-called single cell type) including only one power generation unit 44. Further, the dye-sensitized solar cell 10 may not have the protective layer 2 and the take-out wiring 3.

In addition, it is possible to replace the components in the embodiment with well-known components as appropriate without departing from the spirit of the present invention, and the above-mentioned modifications may be appropriately combined.

1,1A, 1B, 1C, 1D, 1E Dye-sensitized solar cell with protective layer (solar cell module with protective layer)
2 Protective layer 2a Aperture 3 Wiring 10 Dye-sensitized solar cell (solar cell module)
12 Inorganic semiconductor layer (semiconductor layer)
14 Charge transfer body (electrolyte solution)
21 Optical electrode support (base material)
22 Counter electrode support (base material)
31 Optical electrode conductive layer (transparent electrode film)
32 Counter electrode conductive layer (transparent electrode film)
41 Optical electrode 42 Opposite electrode 44 Power generation unit 46 Encapsulant 71 Extraction electrode unit 72 Extension electrode film

Claims (6)

Light electrodes and counter electrodes whose surfaces face each other at intervals,
An electrolytic solution filled between the optical electrode and the counter electrode,
A sealing material that seals the electrolytic solution between the light electrode and the counter electrode to form a power generation unit.
A take-out electrode portion provided on the optical electrode or the counter electrode and electrically connected to the power generation portion, and a take-out electrode portion.
A solar cell module including an extension electrode film electrically connected to the take-out electrode portion, extended from the take-out electrode portion, and arranged so as to cover at least one portion of the back surface of the counter electrode. The optical electrode includes a transparent electrode film and a semiconductor layer on which a dye is adsorbed and laminated on the transparent electrode film.
The solar cell module according to claim 1, wherein the extension electrode film overlaps at least a part of the semiconductor layer in a plan view of the light electrode. A plurality of the semiconductor layers are arranged at intervals in the first direction.
The encapsulant is arranged between the semiconductor layers adjacent to each other in the first direction, and a plurality of power generation units are formed along the first direction.
The power generation units adjacent to each other in the first direction are electrically connected to each other.
The solar cell module according to claim 2, wherein the take-out electrode portion is provided at an end portion of the optical electrode or the counter electrode in the first direction. The light electrode and the counter electrode each include a base material and a transparent electrode film laminated on the surface of the base material.
The take-out electrode portion is provided on the transparent electrode film of the light electrode or the transparent electrode film of the counter electrode.
The solar cell module according to claim 1, wherein the extension electrode film is arranged so as to extend from the take-out electrode portion and cover at least one portion of the back surface of the base material of the counter electrode. The solar cell module according to any one of claims 1 to 4.
A solar cell module with a protective layer comprising a protective layer that protects the solar cell module. The solar cell module with a protective layer according to claim 5, further comprising a take-out wiring electrically connected to the extension electrode film through an opening formed in the protective layer.

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