JP2008065999A - Solar cell module and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solar cell module improved in power generation efficiency by suppressing reverse electron movement without increasing an internal resistance. <P>SOLUTION: The solar cell module is constructed by having a porous oxide semiconductor layer 5 carrying sensitizing dyes, and comprises a first electrode functioning as a window electrode and a second electrode arranged opposed to the first electrode through an electrolyte layer at least at a part, and a first base material having the first electrode or a second base material having the second electrode has a partition part to separate adjoining unit cells. In the first base material, a first conductive layer consisting of a transparent conductive film and a second conductive layer consisting of a tin oxide film are arranged overlapped in the order in a region to make partition parts. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a solar cell module in which unit cells of wet solar cells (hereinafter abbreviated as DSC (Dye-Sensitized Solar Cell)) including a dye-sensitized solar cell are connected in series, and a method for manufacturing the same. .

  There are two methods for increasing the size of DSC: a method in which wiring is provided in a cell and current is obtained by lowering the internal resistance, and a cell is divided in a substrate and each cell is connected in series to provide a high voltage and low current. There is a method to make the module. Among these, as the method of forming a series DSC module in a single substrate as in the latter, modules called Z-type and W-type named from the current path shape are known (for example, Patent Document 1). reference).

  As shown in FIGS. 5 and 6, for example, the modules called Z-type and W-type each receive light incident on a transparent substrate having a three-layer structure including a base material 101, a transparent conductive layer 102, and a semiconductor layer 103. On the other hand, the working electrode (window side electrode) 108 is used as the counter electrode 109, and the working electrode 108 and the counter electrode 109 sandwich the electrolyte layer (electrolytic solution or electrolyte gel) 105. It has a structure.

  As shown in FIG. 5, in the Z-type module, the cells 110a, b, c,... Divided by the partition wall 106 are arranged so that the working electrode 108 is on one side and the counter electrode 109 is on the other side. The working electrodes 108 and the counter electrodes 109 of the adjacent cells 110 a, b, c... Are connected together using an inter-cell connecting member 107 and are electrically connected.

  On the other hand, in the W-type module, as shown in FIG. 6, each cell 110a, b, c... Divided by the partition wall 106 is arranged so that the adjacent working electrode 108 and counter electrode 109 are alternately arranged. The working electrode 108 and the counter electrode 109 of a pair of adjacent cells 110a, 110b, 110c... Are provided on the same base material 101 and connected.

  Among them, the Z-type module does not have unit cells that are back-incident with inferior photoelectric conversion efficiency unlike the W-type module, so that the power generation efficiency in module units can be improved compared to the W-type module. However, since the configuration for connecting the working electrode and the counter electrode is complicated, the Z-type module has problems such as low workability at the time of manufacture and many manufacturing steps, resulting in an increase in manufacturing cost. .

As a method for obtaining good characteristics in a Z-type module, for example, a conductive material containing a conductive agent in an insulating material made of an olefin resin is provided between the working electrode and the counter electrode, and the gap between the two electrodes is electrically There has been proposed one that is connected to (see, for example, Patent Document 2).
In addition, as a structure further advanced from the Z-type module, an idea to realize a monolithic module in which unit cells are arranged side by side on one substrate and the adjacent unit cells are electrically connected is also proposed. (For example, refer to Patent Document 3).

  When producing a Z-type module that is advantageous in terms of power generation efficiency, a large number of unit cells must be arranged side by side on the substrate, and the working electrode and counter electrode of each adjacent cell must be connected in series using a connecting member. However, since the region used for connection is a non-power generation region, it is necessary to make it as narrow as possible. In addition, development of a structure excellent in separability between unit cells is expected so that the electrolyte does not travel between adjacent unit cells.

  In view of this, a module having a configuration in which a base member provided with any one electrode (counter electrode or working electrode) is provided with a partition wall that separates adjacent unit cells is devised. (See Patent Document 4).

  As shown in the example in which the partition wall is provided on the working electrode in FIG. 7, this module includes a first base material 122 made of a transparent member having a partition wall 121 that separates adjacent unit cells 120, and a first electrode. A structure including the conductive layer 123 functioning as a conductive layer and the porous oxide semiconductor layer 124 provided over the conductive layer is used as a window electrode (working electrode) substrate 125 on the light incident side. On the other hand, a structure including the second base material 126, the conductive layer 127 functioning as the second electrode, and the electrode member 128 is referred to as a counter electrode substrate 129. An electrolyte layer 130 (electrolytic solution or electrolyte gel) is provided between the window electrode substrate 125 and the counter electrode substrate 129. Further, one end of the conductive layer 123 of the window electrode substrate 125 extends to the top surface of the partition wall 121, and is configured to be indirectly connected by providing a conductive adhesive member 131 between the top surface and the counter electrode substrate 129. Is.

  According to this configuration, the configuration between adjacent unit cells is simplified as compared with the conventional case, and as a result, the ease of assembly can be significantly improved. In addition, since the adjacent unit cells are connected to each other using the partition wall, only the thickness of the partition wall is adjusted, and the portion used as a connection between the unit cells to become a non-power generation region is narrowed as much as possible. Can be configured.

By the way, as a base material used in such a module, a plastic substrate on which ITO is formed is widely used. In the window-side electrode of a dye-sensitized solar cell using a plastic substrate, reverse electron transfer is likely to occur between the amorphous to microcrystalline ITO transparent conductive film formed on the plastic substrate at a low temperature and the electrolytic solution [ FIG. 7 (b)]. As a result, the power generation efficiency decreases due to the reduction in the shape factor FF due to the decrease in the internal resistance element Rsh.
As a measure for improving the internal resistance element Rsh, it has been reported that a reverse electron transfer layer made of TiO ₂ or the like is formed [FIG. 7 (c)]. The power generation efficiency is lowered due to the decrease in the shape factor FF due to the increase in the internal resistance element Rs.
JP-A-8-306399 JP 2005-93252 A JP 2004-303463 A Japanese Patent Application No. 2005-190247

The present invention has been devised in view of such a conventional situation, and it is a first object to provide a solar cell module with improved power generation efficiency by suppressing reverse electron transfer without increasing internal resistance. Objective.
Further, the present invention provides a method for manufacturing a solar cell module capable of obtaining a solar cell module with improved power generation efficiency by suppressing reverse electron transfer without increasing internal resistance even under low temperature film formation process conditions. The second purpose is to provide it.

The solar cell module according to claim 1 of the present invention includes a porous oxide semiconductor layer carrying a sensitizing dye, a first electrode functioning as a window electrode, and at least a part of an electrolyte layer A first electrode provided with the first electrode or a second substrate provided with the second electrode is provided between adjacent unit cells. In the solar cell module having a partition wall part to be separated, the first base material has a first conductive layer made of a transparent conductive film and a second conductive layer made of a tin oxide film in order in a region between the partition wall parts. It is characterized by being arranged in layers.
The solar cell module according to claim 2 of the present invention is the solar cell module according to claim 1, wherein one end of the first conductive layer has one side surface of the partition wall and a top surface connected to the one side wall, or the partition wall. It extends so that the area | region which opposes may be covered.
The method for producing a solar cell module according to claim 3 of the present invention comprises a porous oxide semiconductor layer carrying a sensitizing dye, a first electrode functioning as a window electrode, and at least a part thereof A first base material on which the first electrode is provided or a second base material on which the second electrode is provided is an adjacent unit. A solar cell module having partition walls separating cells, wherein the first base material is a second conductive layer composed of a transparent conductive film and a tin oxide film in a region between the partition walls. It is a manufacturing method of the solar cell module with which the layers are arranged in order, and the second conductive layer is formed at 200 ° C. or less.

In the present invention, in the first electrode functioning as the window electrode, in the region formed between the partition walls, the first conductive layer made of a transparent conductive film and the second conductive layer made of a tin oxide film are sequentially stacked and arranged. Reverse electron transfer can be suppressed without increasing the internal resistance. Thereby, a solar cell module with improved power generation efficiency can be provided.
Moreover, in this invention, it can be set as the film which can suppress a reverse electron transfer, without increasing an internal resistance by forming a tin oxide film as a said 2nd conductive layer at the temperature of 200 degrees C or less. Therefore, the present invention provides a manufacturing method capable of constructing a solar cell module with improved power generation efficiency on a plastic substrate or the like that requires low-temperature film formation.

  Hereinafter, one embodiment of a solar cell module according to the present invention will be described with reference to the drawings.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a solar cell module according to the present invention, which is an example in which a partition wall is arranged on the window electrode substrate side.
The solar cell module 1 according to the present embodiment includes a first base material 2 made of a transparent member provided with a partition wall portion 21 that separates adjacent unit cells 20, and a transparent conductive film that functions as a first electrode. A window electrode (working electrode) on the light incident side of a structure composed of one conductive layer 3 and a second conductive layer 4 made of a tin oxide film and a porous oxide semiconductor layer 5 provided on the tin oxide film. The substrate 6 is used. On the other hand, a structure including the second base material 7, the third conductive layer 8 functioning as the second electrode, and the electrode member 9 is referred to as a counter electrode substrate 10. An electrolyte layer 11 (electrolytic solution or electrolyte gel) is provided between the window electrode substrate 6 and the counter electrode substrate 10.

  Further, in the solar cell module 1 of the present invention, one end of the first conductive layer 3 of the window electrode substrate 6 extends to the top surface of the partition wall 21 for each unit cell, and on the top surface, adjacent unit cells. It is comprised so that it may join electrically and mechanically with the conductive adhesive member 13 provided between the 3rd conductive layers 8 (or electrode member 9) which comprise the counter electrode board | substrate 10 of this.

  In the solar cell module 1 of the present invention, the first base material 2 includes a first conductive layer 3 made of a transparent conductive film on a region between the partition walls 21, that is, on the bottom surface of the recess, A second conductive layer 4 made of a tin oxide film is disposed on the conductive layer 3 so as to overlap therewith. Thereby, reverse electron transfer can be suppressed without increasing the internal resistance. As a result, a solar cell module with improved power generation efficiency can be provided.

  Although the ITO conductive layer forming the first conductive layer 3 has been used in the past, the amorphous to microcrystalline ITO conductive layer formed at a low temperature is likely to cause reverse electron transfer to the electrolyte, and is dye-sensitized. When used in a solar cell, the shape factor FF tended to decrease. Examples of methods for solving the decrease in form factor FF caused by the conductive layer in dye-sensitized solar cells are known in which the conductive layer is coated with titanium oxide or niobium oxide. The effect cannot be reproduced when a plastic substrate is used. Probably because the coated layer is in an amorphous state. As a result of studying various materials, the present inventors have found for the first time that a tin oxide (TO) coating is particularly excellent when the coating layer is fired at a low temperature. Based on this, the present invention has been devised.

The second conductive layer 4 made of a tin oxide film according to the present invention is preferably formed by a method capable of forming at a low temperature of 200 ° C. or lower, such as a sputtering method.
Since the tin oxide film formed by the above method has low conductivity, it can be used for collecting current from a porous oxide semiconductor layer made of titanium oxide or the like, but can be used as a partition wall for connecting to an adjacent cell. It cannot be used in places where current concentrates like the portion 21. Therefore, it is necessary to perform patterning while avoiding the partition wall portion 21 and to have a structure in which the first conductive layer 3 directly contacts the third conductive layer 8 (or the electrode member 9) constituting the counter electrode substrate 10 on the top surface of the partition wall portion 21. is there.

  The [ITO (crystal) / FTO (fluorine-doped TO: crystal)] composite film having a structure very similar to the [ITO (amorphous) / TO (amorphous)] composite film according to the present invention is disclosed in Japanese Patent Application No. 2003-2003. In [0158], [ITO (crystal) / TO (crystal)] composite films are exemplified in Japanese Patent Application Laid-Open No. 05-294673, but each of them aims to improve heat resistance. The effect of improving the form factor when applied to a battery is not praised.

  The first base material 2 is not particularly limited as long as it is a transparent member having electrical conductivity that conducts electricity by forming a film (layer) made of a conductive material on the surface and having high light transmittance. As this 1st base material 2, plastics, such as a polyethylene terephthalate (PET), a polyethylene naphthalate (PEN), and a polycarbonate (PC), can be used.

In the case of this embodiment, the partition part 21 which isolate | separates between the adjacent unit cells 20 is integrated with the 1st base material 2, For example, it forms by giving unevenness | corrugation to the surface of the 1st base material 2. be able to. This uneven | corrugated process can be performed by using an etching method etc., when a glass plate is used as the 1st base material 2. FIG. Moreover, when the 1st base material 2 is a plastics, an uneven | corrugated process can be given by simple methods, such as injection molding and the cutting method die stamp method. In addition, when plastic is used for the first base member 2, a lightweight module can be obtained economically.
In this way, the unevenness is applied to the first base material 2, and the partition wall portion 21 is formed integrally with the first base material 2, so that the conductive adhesive member 12 that adheres the bipolar substrate and the electrolyte layer 11 are in contact with each other. The area is reduced, the chemical resistance of the cell is improved, and the problem of dark current is less likely to occur.

  Further, since the first base material 2 undergoes a hot pressing process, the plastic used at this time is preferably an engineering plastic having a heat resistant temperature of 130 ° C. or higher, such as polycarbonate or polyarylate.

  The first conductive layer 3 is a conductive film made of a conductive material formed on the first substrate 2, and for example, tin-added indium (ITO) is preferable. When the 1st conductive layer 3 is formed on the 1st base material 2, the thing with a high light transmittance is suitable.

The first conductive layer 3 is provided so as to cover only one side surface of the partition wall 21 and the top surface continuous therewith, and acts as an inter-cell connecting member that connects cell structures in adjacent positions in series. . Therefore, in the case of the present embodiment, the window electrode and the counter electrode can be electrically connected using the first conductive layer 3 as it is.
And the window electrode (working electrode) board | substrate is set by forming the transparent 1st conductive layer 3 with a high light transmittance on the 1st base material 2. FIG.

The porous oxide semiconductor layer 5 is provided on the second conductive layer 4 made of a tin oxide film, and a sensitizing dye is supported on the surface thereof. The semiconductor for forming the porous oxide semiconductor layer 5 is not particularly limited, and any semiconductor can be used as long as it is generally used for forming a porous oxide semiconductor for a photoelectric conversion element. As such a semiconductor, for example, titanium oxide (TiO ₂ ), tin oxide (SnO ₂ ), tungsten oxide (WO ₃ ), zinc oxide (ZnO), niobium oxide (Nb ₂ O ₅ ), or the like can be used. .

  As a method for forming the porous oxide semiconductor layer 5, for example, a dispersion obtained by dispersing commercially available oxide semiconductor fine particles in a desired dispersion medium or a colloidal solution that can be prepared by a sol-gel method is used as necessary. After adding a desired additive, after applying by a known coating method such as a screen printing method, an ink jet printing method, a roll coating method, a doctor blade method, a spray coating method, etc., this solvent is removed by heat treatment to remove voids. A method of forming and making it porous can be applied.

  As the sensitizing dye, a ruthenium complex containing a bipyridine structure or a terpyridine structure as a ligand, a metal-containing complex such as porphyrin or phthalocyanine, or an organic dye such as eosin, rhodamine or merocyanine can be applied. Therefore, those exhibiting behavior suitable for the intended use and the semiconductor used can be selected without particular limitation.

  On the other hand, the 2nd base material 7 does not need to be a member provided with electroconductivity by providing the 3rd conductive layer 8 which functions as a 2nd electrode in the inner surface, and is a highly light-transmissive member, and is not restrict | limited. As the second substrate 7, a glass plate is generally used, but other than the glass plate, for example, plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polycarbonate (PC). Ceramics such as titanium oxide and alumina can be used. Especially, as the 2nd base material 7, in order to suppress generation | occurrence | production of the curvature resulting from thermal expansion, the material same as the 1st base material 2 which comprises a window pole, or the material of a substantially the same thermal expansion coefficient is preferable. In addition, as a conductive layer provided in the inner surface of the 2nd base material 7, the member similar to the conductive layer mentioned above is used.

  The electrode member 9 is an electrode that generates an electromotive force with the window electrode. For example, chemically stable platinum or carbon is preferably used. As for the method of forming the electrode member 9, for example, when the electrode member 9 is made of platinum, a vacuum film-forming method such as sputtering or vapor deposition, or a wet process in which a heat treatment is applied after applying a platinum-containing solution such as a chloroplatinic acid solution to the substrate surface It can be performed using a film formation method or the like.

The electrolyte solution forming the electrolyte layer 11 refers to a solution having electrical conductivity by dissociating the electrolyte in the solution to generate cations and anions. As the electrolytic solution, for example, an organic solvent containing a redox pair, an ionic liquid (room temperature molten salt), or the like can be used.
The oxidation-reduction pair is not particularly limited. For example, iodine / iodide ion, bromine / bromide ion, etc. can be selected. In the former case, iodide salt (lithium salt, quaternized imidazolium salt, tetra Butylammonium salt or the like can be used alone or in combination) and iodine can be provided by adding alone or in combination.

Examples of the organic solvent include volatile electrolytes using acetonitrile, methoxyacetonitrile, propionitrile, ethylene carbonate, propylene carbonate, diethyl carbonate, γ-butyrolactone, and the like.
Examples of the ionic liquid include those using, as a cation, a compound having a quaternized nitrogen atom such as a quaternized imidazolium derivative, a quaternized pyridinium derivative, or a quaternized ammonium derivative.

In addition, a so-called gel electrolyte obtained by suppressing the fluidity by introducing an appropriate gelling agent and filler into the electrolyte solution, that is, a so-called gel electrolyte, may be used as the electrolyte layer 11.
Various additives such as lithium salt and tert-butylpyridine may be further added to the electrolytic solution as necessary. Further, a polymer solid electrolyte having a charge transporting ability as in the case of such an electrolytic solution may be used as the electrolyte layer 11.

  The conductive adhesive member 12 is preferably an anisotropic conductive adhesive that is joined by heating and pressing. An anisotropic conductive adhesive is a connecting material that has the three functions of adhesion, conductivity, and insulation. By thermocompression bonding, the electrical conductivity is electrically different in the thickness direction and insulating in the surface direction. Has a direction. Examples of the conductive adhesive member 12 include pasty ACP (Anisotropic Conductive Paste). In order to improve conductivity, it is also effective to combine a metal conductor with an anisotropic adhesive. When used in combination with a metal conductor, NCP (Non Conductive Paste) or NCF (Non Conductive Film), which is an insulating adhesive member, may be used instead of the anisotropic conductive adhesive.

Then, the window electrode substrate 6 and the counter electrode substrate 10 are arranged so that the porous oxide semiconductor layer 5 provided on the window electrode substrate 6 and the electrode member 9 provided on the counter electrode substrate 10 face each other. A conductive adhesive member 12 is disposed between the first conductive layer 3 provided on the top surface of the partition wall 21 and the third conductive layer 8 (or electrode member 9) of the counter electrode substrate 10 to indirectly connect the heat. Laminate by press.
Thereafter, an electrolytic solution is injected into the cell and sealed to obtain a solar cell module 1 in which unit cells 20 are connected in series as shown in FIG.

Below, an example of the manufacturing method of the solar cell module 1 which concerns on this invention is demonstrated.
FIG. 2 is a schematic cross-sectional view sequentially illustrating the steps of manufacturing the window electrode (working electrode) substrate 6 constituting the solar cell module 1, and FIG. 3 sequentially illustrates the steps of manufacturing the counter electrode substrate 10 in the solar cell module 1. It is a schematic sectional drawing shown. And FIG. 4 is a schematic sectional drawing which shows the manufacture example of the solar cell module 1 which concerns on this invention.

First, a method for producing a window electrode (working electrode) will be described with reference to FIG.
As shown to Fig.2 (a), the 1st base material 2 which can give an uneven | corrugated process is prepared. The first substrate 2 may be a general-purpose glass plate, but is preferably a resin plate (plastic plate) that can be easily processed with unevenness and that can provide an economical and lightweight module.

  Next, as shown in FIG. 2 (b), the concave and convex portions 21 and the convex portions (hereinafter referred to as the partition wall portions 21) are formed by subjecting one surface of the first base material 2 to uneven processing. Thereby, this convex part becomes what was integrated with the 1st base material 2, and functions as the partition part 21 which isolate | separates between the adjacent unit cells 20. FIG. Examples of the unevenness processing method include simple methods such as injection molding, cutting, and die stamping.

  The depth of the concave portion 21 (that is, the height of the convex portion) is preferably 100 μm or less and more than the thickness of the porous oxide layer in view of the inter-plate distance. If the depth of the recess 21 is 100 μm or more, the electrolyte layer 11 is too thick and the internal resistance becomes large, which is not preferable. On the other hand, if the depth of the recess 21 is shallower than the thickness of the porous oxide layer, the counter electrode collides with the counter electrode. This is because the porous oxide layer is not accommodated between the two electrodes.

  Next, as shown in FIG. 2C, the first conductive layer 3 made of a transparent conductive film is provided on the surface of the first base material 2 that has been subjected to the uneven processing. The first conductive layer 3 may be formed using a known method according to the material constituting the first conductive layer 3. For example, a sputtering method, a CVD method (vapor phase growth method), an SPD method ( A thin film made of an oxide semiconductor such as tin-added indium oxide (ITO) is formed by spray pyrolysis deposition method) or vapor deposition method. If the first conductive layer 3 is too thick, the light transmittance is inferior. On the other hand, if it is too thin, the conductivity is impaired. The film thickness is preferably about 030 μm to 1 μm.

  Subsequently, as shown in FIG. 2C, a resist (not shown) is formed on the formed first conductive layer 3 by a screen printing method or the like, and the first conductive layer 3 is formed using this resist as a mask. Remove some of the. Thereafter, by removing the resist, the first conductive layer 3 is formed so that one end thereof covers one side surface of the partition wall portion 21 and the top surface continuous therewith on one surface of the first base material 2 that has been subjected to the uneven processing. Is made. Thereby, the electroconductive board | substrate for window electrodes is obtained.

Further, as shown in FIG. 2 (d), in the conductive substrate for the window electrode, the second conductive material made of a tin oxide film is formed on the first conductive layer 3 formed on the bottom surface of the concave portion forming the partition wall portion 21. Layer 4 is formed in an overlapping manner. If the second conductive layer 4 is too thick, the conductivity is impaired. On the other hand, if the second conductive layer 4 is too thin, the effect of preventing reverse current cannot be sufficiently obtained. For example, in the case of a SnO ₂ film, the second conductive layer 4 has a thickness of about 5 nm to 100 nm. Good.

Here, the present invention is characterized in that the second conductive layer 4 is formed by a method capable of forming a film at a low temperature of 200 ° C. or lower, such as a sputtering method. Thereby, the tin oxide film 4 can be made into a film that can suppress reverse electron transfer without increasing the internal resistance.
Since the second conductive layer 4 made of a tin oxide film formed at a relatively low temperature of 200 ° C. or lower has low conductivity, it can be used for a current density of about the current collection from the titanium oxide electrode, but connected to an adjacent cell. Therefore, it cannot be used in a location where current is concentrated, such as the partition wall portion 21. Therefore, it is necessary to perform patterning while avoiding the partition wall 21.

Furthermore, as shown in FIG. 2E, a porous oxide semiconductor layer 5 is formed on the second conductive layer 4 made of a tin oxide film. As a method for forming the porous oxide semiconductor layer 5, for example, a paste is prepared by mixing a powder of titanium dioxide (TiO ₂ ) with a dispersion medium, and this is prepared by a screen printing method, an ink jet printing method, a roll coating method, a doctor blade, or the like. It is applied onto the conductive layer by the method, spin coating method, etc. and baked. And this porous oxide semiconductor layer 5 is formed in about 1 micrometer-20 micrometers.

  And as shown in FIG.2 (e), the window electrode board | substrate 6 is comprised by making a sensitizing dye carry | support between the particle | grains of the porous oxide semiconductor layer 5. FIG. The sensitizing dye can be supported, for example, by immersing the conductive substrate on which the porous oxide semiconductor layer 5 is formed in the dye solution.

Next, a method for manufacturing the counter electrode substrate 10 will be described with reference to FIG.
As shown in FIG. 3A, a second base material 7 made of plastic is prepared, and a third conductive layer 8 is provided on one surface of the second base material 7. As a method for forming the third conductive layer 8, similarly to the case of the first substrate 2, a known method may be used according to the material of the third conductive layer 8, for example, a sputtering method, a vapor deposition method, or the like. Thus, a thin film made of an oxide semiconductor such as tin-added indium oxide (ITO) is formed. If the conductive layer 8 is too thick, the light transmittance is inferior. On the other hand, if it is too thin, the conductivity is impaired. For example, in the case of an ITO film, considering both the light transmittance and the conductivity, 0.030 μm to The film thickness is preferably about 2 μm.

  Subsequently, as shown in FIG. 3B, a resist (not shown) is formed on the formed third conductive layer 8 by a screen printing method or the like, and the resist is used as a mask to form the third conductive layer 8. Remove some of the. Thereafter, by removing the resist, the third conductive layer 8 having a desired unit cell pattern is produced. Thereby, the electroconductive board | substrate for counter electrodes is obtained.

  Next, as shown in FIG. 3C, a resist α that can be stripped in advance is formed on the patterned third conductive layer 8 on the patterned conductive substrate 8 by a screen printing method or the like. An electrode member 9 is formed so as to cover the three conductive layers 8 and the resist. As this electrode member 9, for example, platinum or carbon can be used, which can be formed by a vacuum film-forming method such as a sputtering method or a vapor deposition method, or a wet method in which a platinum-containing solution such as a platinum chloride solution is applied to the substrate surface and then heat treatment is applied. You may form by the film-forming method etc. The thickness of the electrode member 9 is preferably about 0.01 μm to 5 μm. If it is thinner than 0.01 μm, the effective area of the electrode is insufficient, and if it exceeds 5 μm, the film formation cost becomes excessive, which is not preferable.

  Thereafter, a part of the electrode member 9 positioned thereon is removed from the second base material 7 together with the resist α. As a result, the counter electrode substrate 10 having the configuration shown in FIG.

  Then, as shown in FIG. 4A, a porous oxide semiconductor in which the window electrode substrate 6 shown in FIG. 2E and the counter electrode substrate 10 shown in FIG. The layer 5 and the electrode member 9 provided on the counter electrode substrate 10 are arranged so as to face each other, and the first conductive layer 3 provided on the top surface of the partition wall portion 21 of the window electrode substrate 6 and the third conductive layer 8 of the counter electrode substrate 10. (Or the electrode member 9), the conductive adhesive member 12 is disposed and indirectly connected, and bonded by hot pressing (see FIG. 4B).

Thereafter, an electrolytic solution is injected into the cell and sealed to obtain a solar cell module 1 in which unit cells 20 are connected in series as shown in FIG.
The solar cell module 1 thus obtained has a second conductive layer made of a tin oxide film on a first conductive layer 3 made of a transparent conductive film formed on the bottom surface of a recess formed between partition walls in a window electrode substrate. By arranging the layers 4 in an overlapping manner, reverse electron transfer can be suppressed without increasing the internal resistance. As a result, the power generation efficiency is improved.

Although the solar cell module of the present invention has been described above, the present invention is not limited to the above example, and can be appropriately changed as necessary.
For example, FIG. 1 shows an embodiment of a solar cell module in which the partition wall portion is disposed on the window electrode substrate side, although not illustrated, the partition wall portion may be disposed on the counter electrode substrate side. The above-described actions and effects of the present invention can be obtained. However, when the partition wall portion is disposed on the counter electrode substrate side, the first conductive layer is different from the arrangement example of FIG. 1 in that one end of the first conductive layer extends so as to cover a region facing the partition wall portion. .

  The present invention is widely applicable to a solar cell module in which unit cells of wet solar cells including a dye-sensitized solar cell are connected in series and a method for manufacturing the same.

It is a schematic sectional drawing which shows an example of the solar cell module of this invention. It is a schematic sectional drawing which shows the process of producing a window electrode (working electrode) board | substrate. It is a schematic sectional drawing which shows the process of producing a counter electrode board | substrate. It is a schematic sectional drawing which shows the manufacture example of a solar cell module. It is a schematic sectional drawing which shows the structural example of the conventional Z-type solar cell module. It is a schematic sectional drawing which shows the structural example of the conventional W type solar cell module. It is a schematic sectional drawing which shows the structural example of the conventional solar cell module.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Solar cell module, 2 1st base material, 1st conductive layer (1st electrode), 4th 2nd conductive layer (tin oxide film), 5 porous oxide semiconductor layer, 6 window electrode (working electrode) board | substrate, 7 Second substrate, 8 Third conductive layer (second electrode), 9 Electrode member, 10 Counter electrode substrate, 11 Electrolyte layer, 12 Conductive adhesive member, 20 Unit cell, 21 Partition part

Claims (3)

A first electrode that has a porous oxide semiconductor layer carrying a sensitizing dye and functions as a window electrode, and is disposed at least partially opposite to the first electrode via an electrolyte layer A second electrode,
The first base material that provides the first electrode or the second base material that provides the second electrode is a solar cell module having a partition wall that separates adjacent unit cells,
The solar cell, wherein the first base material has a first conductive layer made of a transparent conductive film and a second conductive layer made of a tin oxide film sequentially stacked in a region between the partition walls. module.   One end of the first conductive layer extends so as to cover both one side surface of the partition wall and the top surface connected to the one side wall, or a region facing the partition wall. The solar cell module according to claim 1. A first electrode that has a porous oxide semiconductor layer carrying a sensitizing dye and functions as a window electrode, and is disposed at least partially opposite to the first electrode via an electrolyte layer A second electrode,
The first base material that provides the first electrode or the second base material that provides the second electrode is a solar cell module having a partition wall that separates adjacent unit cells,
The first base material is a method of manufacturing a solar cell module in which a first conductive layer made of a transparent conductive film and a second conductive layer made of a tin oxide film are sequentially stacked in a region between the partition walls. There,
Said 2nd conductive layer is formed at 200 degrees C or less, The manufacturing method of the solar cell module characterized by the above-mentioned.

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