JP2010211971A - Dye-sensitized solar cell and wrist watch equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem in a dye-sensitized solar cell that, although it recently attracts attention as a solar cell for achieving cost reduction or colorful representation and has so unique a structure that a photoexcitation material carrying dyestuff and an electrolyte are enclosed between two sheets of opposed electrodes, such a troublesome work as to attach a lead wire for electric extraction outside is needed due to the basic structure having the electrodes set opposed. <P>SOLUTION: The dye-sensitized solar cell includes a first substrate having a first thin-film electrode, a second substrate having a second thin-film electrode, a semiconductor layer adsorbing dyestuff and in contact with either the first thin-film electrode or the second thin-film electrode, an insulating spacer between the first thin-film electrode and the second thin-film electrode arranged in opposition, and an electrolytic layer in a space surrounded by the first thin-film electrode, the second thin-film electrode and the insulating spacer. A through-hole is formed in the first substrate reaching the first thin-film electrode, and a reinforcing layer is formed on an opposite surface of the first connecting electrode exposed to an inside of the through-hole. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

 The present invention relates to the structure of a dye-sensitized solar cell, and more particularly to the characteristic structure of the external extraction electrode. The present invention also relates to a wristwatch provided with a dye-sensitized solar cell.

  In recent years, in relation to environmental problems, solar cells, which are clean energy sources, have attracted more attention, and their use is being investigated in various places. Generally speaking, most of the solar cells in which a silicon-based semiconductor is laminated, including single crystals, polycrystals, and amorphous, are put into practical use. However, a reduction in manufacturing cost is expected, and dye-sensitized solar cells are attracting attention as a solar cell that can be expressed in a colorful manner not found in silicon-based solar cells. It has been broken.

  Dye-sensitized solar cells are called so-called wet solar cells with electrochemical reactions, unlike the type of silicon solar cell thin film laminated, and have been developed for a long time, Recently, a structure that can be put into practical use has been proposed by Gretzell et al. This is shown in Patent Document 1 or Patent Document 2, for example.

  A conventional dye-sensitized solar cell will be described with reference to FIG. First, on the first substrate 10 made of glass or heat-resistant plastic, a first thin film electrode 11 serving as a catalyst metal is formed to form a counter electrode. As the catalyst metal, a noble metal such as platinum or palladium is used.

  Similarly, a transparent second thin-film electrode 21 such as ITO (Indium Tin Oxide) is formed on the second substrate 20 made of glass, heat-resistant plastic, or the like, and TiO2 (titanium dioxide) is further formed thereon. The fine particle semiconductor layer 30 is formed and provided as a working electrode. Further, the desired dye 31 is adsorbed on the surface of the semiconductor layer.

  The working electrode and the counter electrode are arranged with their conductive surfaces facing each other, and are joined with an insulating spacer 40 serving as an adhesive layer interposed therebetween. A space between both the substrates and the insulating spacer is filled with an electrolyte layer 50 capable of performing a redox reaction. In general, many electrolyte layers use iodine redox.

The principle of operation is as follows. External light that has entered from the second substrate 20 side passes through the semiconductor layer 30 and is absorbed by the dye 31 carried on the surface thereof. Thereby, the electrons in the dye 31 are excited from the ground state to the excited state. The excited electrons quickly move to the adjacent semiconductor layer 30 and reach the second thin film electrode 21 through the semiconductor layer 30. And it reaches the 1st thin film electrode 11 which is a counter electrode via an external circuit.
On the other hand, the dye 31 that has lost electrons draws electrons from the reducing agent in the electrolyte layer 50 and is reduced to the original state. The oxidized reducing agent receives the electrons that have moved to the counter electrode, and It becomes a reducing agent in the original state. Thus, the dye-sensitized solar cell can absorb light and flow electrons to an external circuit, and has a so-called photovoltaic effect.

Japanese Patent No. 3336528 (FIG. 1) Japanese Patent No. 4085421 (FIG. 1)

  As described above, the dye-sensitized solar cell is a light energy conversion device that works by utilizing the internal oxidation-reduction reaction, and many structures have been developed for basic power generation. Little consideration has been given to the method of extracting generated energy.

  Although it has been stated that electrons generated by light absorption move between both electrodes via an external circuit, the place where the electrons are connected to the external circuit is, for example, an electrode portion that protrudes from the insulating spacer 40 as in the lead wire 25 shown in FIG. It is common to use.

  If the dye-sensitized solar cell is used in a large area, for example, when used for power generation outdoors, it is considered that such a pulling-out method can also be used because a sufficient space can be used. However, the use of solar cells is not limited to large-scale power generation, and is often used in consideration of convenience in combination with various electronic devices. For example, as a typical example, it is expected to be used as a system that can be mounted on a wristwatch or a calculator and can operate for a long time without a primary battery.

  For example, when a dye-sensitized solar cell is mounted on a wristwatch, it is necessary to attach the solar cell and connect wiring in a very narrow space. Handling the two conventional lead wires 25 is very troublesome because the two wires having different lengths and lead-out directions are individually electrically connected. In addition, the space becomes inefficient.

  Therefore, in mounting in a limited place such as a wristwatch, for example, a pin for conduction is raised from an external circuit, and a solar cell is simply placed on the pin, so that the electrode portion of the solar cell and the pin are in contact with each other. To get continuity with. However, in the conventional dye-sensitized solar cell, since the electrodes on the upper and lower substrates are in opposite positions, it is impossible to contact both electrodes simultaneously from one direction. I can't take it either.

  Then, the objective of this invention is providing the dye-sensitized solar cell which solves the said subject and can be easily connected with the exterior.

  In order to achieve the above object, the following means are employed in the dye-sensitized solar cell of the present invention.

 A first substrate having a first thin film electrode; a second substrate having a second thin film electrode; a semiconductor layer in contact with either the first thin film electrode or the second thin film electrode and adsorbing a dye; An insulating spacer disposed between the first thin film electrode and the second thin film electrode, and an electrolyte layer filled in a space surrounded by the first thin film electrode, the second thin film electrode, and the insulating spacer. The dye-sensitized solar cell has a structure in which a through hole reaching the first thin film electrode is provided in the first substrate.

  The surface of the first thin film electrode exposed inside the through hole is the first connection electrode, and the first thin film electrode opposite to the first connection electrode has a reinforcing layer, and the insulating spacer functions as the reinforcing layer. It can also be combined. The second substrate preferably has a portion extending from the outer periphery of the first substrate, and the extended portion preferably has a second connection electrode.

 Furthermore, it is preferable to have a conductive spacer that is in electrical contact with the second thin film electrode and reaches the first substrate in a state of being insulated from the first thin film electrode. An auxiliary electrode is provided between the conductive spacer and the first substrate. Even better.

 A first through hole is provided on the opposite surface of the first substrate to which the reinforcing layer or the insulating spacer comes into contact, and the first connection electrode is exposed inside the first through hole, and the first contact hole comes into contact with the conductive spacer. It is preferable that a second through hole is provided on the opposite surface of one substrate, and the second connection electrode is exposed inside the second through hole.

 It is more preferable to have a first electrode pad that is in electrical contact with the first connection electrode inside the through hole, or a second electrode pad that is in electrical contact with the second connection electrode.

  In the wristwatch in which the display board, the movement, and the circuit board are mounted in the space formed by the case, the windshield, and the back cover, the dye-sensitized solar cell of the present invention is disposed between the display board and the movement. Is mounted so as to be opposed to the display panel, and electrically connected to the circuit board having the first connection electrode and the second connection electrode opposed to each other using a conductive terminal. The conductive terminal is connected to the circuit board in advance. It may be provided.

  In the dye-sensitized solar cell of the present invention, through-holes are formed on one substrate and the exposed electrode surface is used, so that the upper and lower electrodes can be taken out from the same direction. Thereby, since it is not necessary to route the lead wire as in the conventional case, the material and the process can be reduced. In particular, when the dye-sensitized solar cell of the present invention is mounted in a limited narrow region, it is advantageous as space efficiency that no lead wire is routed.

  And since the two electrodes of the dye-sensitized solar cell of the present invention face in the same direction, the circuit board and the like of the connection destination are opposed to each other, and by interposing a springy conductive terminal, soldering or A simpler connection than before is possible without bonding. When a reinforcing layer is provided on the surface opposite to the electrode surface exposed in the through hole, the electrode film has a structure that can withstand strength even when a force such as a pin is constantly applied.

  In addition, by providing the insulating spacer with the effect of the reinforcing layer, the manufacturing process of the reinforcing layer can be simplified and the insulating spacer can be arranged close to the outer periphery, so that the power generation area can be broadened widely. The performance can be improved.

  Furthermore, since a conductive spacer is brought into contact with the thin film electrode of the second substrate and the conductive spacer reaches the first substrate, electrical extraction from one substrate to the outside becomes possible. In addition, by forming two through holes in the first substrate, simple external connection on the same surface becomes possible.

  The dye-sensitized solar cell as described above, for example, is mounted under the display board inside a wristwatch, and can be easily connected with an intervening conductive terminal by facing the circuit board and the connection electrode in the movement. Can and is very effective.

It is sectional drawing which showed the dye-sensitized solar cell of the 1st Example in embodiment of this invention. It is the top view which looked at the dye-sensitized solar cell of the 1st Example in embodiment of this invention from the 1st board | substrate side. It is sectional drawing which showed the dye-sensitized solar cell of the 1st Example in embodiment of this invention. It is sectional drawing which showed the dye-sensitized solar cell of the 2nd Example in embodiment of this invention. It is sectional drawing which showed the dye-sensitized solar cell of the 3rd Example in embodiment of this invention. It is sectional drawing which showed the dye-sensitized solar cell of the 3rd Example in embodiment of this invention. It is sectional drawing which showed the dye-sensitized solar cell of the 3rd Example in embodiment of this invention. It is sectional drawing which showed the dye-sensitized solar cell of the 3rd Example in embodiment of this invention. It is the top view which looked at the dye-sensitized solar cell of the 3rd Example in embodiment of this invention from the 1st board | substrate side. It is sectional drawing of the wristwatch which mounted the dye-sensitized solar cell in embodiment of this invention. It is principal part sectional drawing in the case of mounting the dye-sensitized solar cell in embodiment of this invention in a wristwatch. It is principal part sectional drawing in the case of mounting the dye-sensitized solar cell in embodiment of this invention in a wristwatch. It is sectional drawing which showed the conventional dye-sensitized solar cell.

[Example 1]
First, the structure of the solar cell of the present invention will be described with reference to FIG. FIG. 1 shows a cross-sectional structure of the dye-sensitized solar cell of the present invention.
The basic components of the dye-sensitized solar cell of the present invention are the first substrate 10, the first thin film electrode 11, the second substrate 20, the second thin film electrode 21, the semiconductor layer 30, the dye 31, the insulating spacer 40, the electrolyte. It consists of a layer 50 and a reinforcing layer 70.

 The first substrate 10 uses a transparent film material. In the present invention, PEN (polyethylene naphthalate) is used, but other PET (polyethylene terephthalate), PC (polycarbonate), PI (polyimide), PA (polyamide). ), PAI (polyamideimide), etc., heat-resistant polymer materials can be used.

 A first thin film electrode 11 is formed on the first substrate 10, and a metal thin film having catalytic activity is used here. Platinum is mainly used, but palladium, rhodium, osmium, iridium, etc. can also be used. In addition, since these metals are expensive, a very thin film may be formed, and another metal material, an oxide semiconductor layer, or the like may be interposed thereunder for electrical conduction.

 The second substrate 20 is also made of a transparent film material in the same manner as the first substrate 10. A second thin film electrode 21 is formed on the surface of the film. The second thin film electrode 21 is made of a transparent oxide semiconductor such as ITO (Indium Tin Oxide), tin dioxide, or zinc oxide.

Further, a semiconductor layer 30 made of titanium dioxide fine particles is formed on the second thin film electrode 21. The dye 31 is adsorbed on the surface of the semiconductor layer 30. In addition, tin oxide, tungsten oxide, zinc oxide, niobium oxide, and the like can be used for the semiconductor layer 30. In addition, as the dye 31, many dye groups such as a ruthenium complex having a bipyridine structure, a metal complex such as porphyrin or phthalocyanine, or an organic dye such as rhodamine, merocyanine, indoline, or coumarin can be used.

 In FIG. 1, the semiconductor layer 30 and the dye 31 are expressed as a film overlapped. However, since the semiconductor layer 30 actually has a porous structure with titanium dioxide fine particles, the infinite number of semiconductor layers 30 are present. The dye 31 is also adsorbed on the surface of the hole, and has a structure that is combined with the semiconductor layer 30.

 The two substrates are arranged in such a manner that both electrodes formed on the surface face each other. An insulating spacer 40 is installed around the semiconductor layer 30 and the two substrates are bonded together with a clearance corresponding to the thickness. For the insulating spacer 40, an adhesive resin such as a hot melt material, a thermosetting resin, or an ultraviolet curable resin is used, which basically serves to bond the upper and lower substrates in addition to keeping the space. .

 The gap between the upper and lower electrodes formed by the insulating spacer 40 is filled with the electrolyte layer 50. The electrolyte layer 50 is made of an electrolyte component such as iodine, iodine compound, or bromine compound dissolved in acetonitrile, ethylene carbonate, polyethylene glycol, methoxypropionitrile, or the like.

 The structure so far is almost the same as that of the conventional dye-sensitized solar cell. However, in the dye-sensitized solar cell of the present invention, the first substrate 10 has a through hole 60 reaching the first thin film electrode 11. . A part of the first thin film electrode 11 is exposed by the through hole 60, and the exposed part is a first connection electrode 65.

 A reinforcing layer 70 is formed on the surface of the first thin film electrode 11 on the opposite surface side of the first connection electrode 65. The reinforcing layer 70 is made of an organic resin such as thermosetting or photocurable, and has a size larger than the diameter of the through hole 60 and covers the entire first connection electrode 65 with the opposite surface. When the first connection electrode 65 is in electrical contact with the outside, stress is applied to the electrode film by some means, and the first connection electrode 65 cannot withstand only the thin electrode film. Thus, the presence of the reinforcing layer 70 enables practical use in terms of strength.

 In the dye-sensitized solar cell of the present invention, the first substrate 10 and the second substrate 20 have almost the same shape, but are partially different. FIG. 2 shows a plan view of the dye-sensitized solar cell of the present invention as viewed from the first substrate 10 side. As seen in FIG. 2, the substantially circular first substrate 10 has a notch 63. Since the second substrate 20 has a circular shape, a part of the second substrate 20 extends from the notch 63 of the first substrate 10, and the portion that appears there is the second connection electrode. 66. In the drawing, the extended portion of the second connection electrode 66 is a cutout portion of the first substrate 10, but it can also be formed by slightly shifting the arrangement of the first substrate 10 and the second substrate 20, for example.

 By adopting the above configuration, in the dye-sensitized solar cell of the present invention, the connection surfaces of the first connection electrode 65 and the second connection electrode 66 for connecting to the outside face in the same direction. That is, both electrodes face downward in FIG. From this, in the dye-sensitized solar cell of this invention, direct connection can be performed by arrange | positioning an external circuit facing the 1st board | substrate 10. FIG.

Although the effects of the present invention can be obtained with the structure shown in FIG. 1, electrode pads may be formed on the connection electrodes of the upper and lower substrates. The structure is shown in FIG. A first electrode pad 81 and a second electrode pad 82 made of conductive resin so as to be in electrical contact with the first connection electrode 65 and the second connection electrode 66.
Is formed. As the conductive resin, an epoxy resin, an acrylic resin, or a silicone resin in which conductive particles such as carbon and silver are kneaded is used. The presence of the electrode pad does not directly contact the thin film electrode when connected to the outside, so there is no risk of film damage and the reliability is further increased.

 Next, a method for producing the dye-sensitized solar cell of the present invention will be briefly described. First, a film-like first substrate 10 is prepared, and a platinum thin film is formed using a sputtering method to form a first thin film electrode 11. At this time, a titanium film may be formed as a base layer. A reinforcing layer 70 is provided on a part of the first thin film electrode 11. The reinforcing layer 70 is formed later on a portion to be used as a connection electrode of the solar cell, but is applied by dispensing or printing an epoxy resin and cured by heat or ultraviolet rays. Although not shown, a minute injection hole for injecting the electrolyte later is formed in the first substrate 10.

 Similarly, a film-like second substrate 20 is prepared, and an ITO thin film is also formed by using the sputtering method to form the second thin film electrode 21. Subsequently, a paste in which fine particles of titanium dioxide are dispersed in an organic solvent such as polyethylene glycol, alcohol, and acetone or water is prepared, and printed on the second thin film electrode 21 in a desired shape using a squeegee method. After the solvent is evaporated to some extent at room temperature, the paste is baked in an electric furnace to form the semiconductor layer 30. At this time, the titanium dioxide particles are bonded to each other to lower the overall resistance.

 Further, a dye solution in which the dye 31 is dissolved in an organic solvent is prepared, and the second substrate 20 is immersed in the dye solution, and the dye 31 is adsorbed on the surface of the titanium dioxide particles as the semiconductor layer 30. The substrate with the dye 31 is completed by heating or natural drying after removing from the solution.

 A hot-melt type adhesive is processed into a desired shape and disposed on the outer periphery of the semiconductor layer 30 formed on the second substrate 20. The first substrate 10 previously prepared is opposed to the second substrate 20 and heated while applying pressure. When the hot melt material is melted, it is compatible with the upper and lower substrates. When the hot melt material is returned to room temperature, it is solidified again to become the insulating spacer 40 and the bonding is completed.

 Subsequently, a laser beam is irradiated from the lower surface of the first substrate 10 to dissolve and remove a part of the first substrate 10 to form a through hole 60. The through hole 60 is formed at the position of the reinforcing layer 70 previously formed, but it is preferable that the through hole 60 be smaller than the area of the reinforcing layer 70. Thereby, the exposed first thin film electrode 11 portion becomes the first connection electrode 65.

 If necessary, the first electrode pad 81 and the second electrode pad 82 are formed on the first connection electrode 65 and the second connection electrode 66 by using a dispensing method or a printing method. The conductive resin to be the electrode pad is completed by placing the stock solution at a predetermined location and then curing it by heating or ultraviolet irradiation.

 Finally, the electrolyte layer 50 is formed by injecting an electrolytic solution into the internal space from a previously formed injection hole of the first substrate 10 using a syringe or the like. The injection hole is sealed by placing a hot melt agent and reheating it. The dye-sensitized solar cell of the present invention is completed through the above steps.

In the above description, the formation of the through hole 60 is performed after the substrates are bonded together. However, the formation of the through hole 60 may be continued after the reinforcing layer 70 is formed on the first substrate 10. Further, the first electrode pad 81 can be formed subsequently. The second electrode pad 82 may be formed anytime after the second thin film electrode 21 is formed. Moreover, since the through hole 60 is formed inside the first substrate 10 in the drawing, it is literally in the shape of a hole, but may be formed in the outer peripheral portion. In this case, it looks like a notch, not a hole, but the insulating spacer 4
If there is 0, the necessary function can be performed.
[Example 2]

 Next, the second structure of the dye-sensitized solar cell of the present invention is shown in FIG. The configuration including the first substrate 10, the first thin film electrode 11, the second substrate 20, the second thin film electrode 21, the semiconductor layer 30, the dye 31, the electrolyte layer 50, and the insulating spacer 40 is the same as the solar cell shown in FIG. The same applies to the second connection electrode 66 in the portion of the second substrate 20 extending from the first substrate 10.

 Here, in the second dye-sensitized solar cell, the through hole 60 is formed on the lower surface of the insulating spacer 40, that is, the insulating spacer 40 also serves as the reinforcing layer 70 described above. Naturally, the size of the through hole 60 is smaller than the width of the insulating spacer 40. However, when the width of the insulating spacer 40 is small, the width of the insulating spacer 40 corresponding to the place where the through hole 60 is opened is widened. You may do it. In this way, the first connection electrode 65 is formed on the lower surface of the insulating spacer 40 and is reinforced by the insulating spacer 40, so that the electrode can be used practically in strength.

In the second dye-sensitized solar cell described above, since the insulating spacer 40 also serves as the reinforcing layer 70, the manufacturing process can be simplified, and the insulating spacer 40 can be disposed close to the outer periphery. It is possible to expand the area over a wide range.
Example 3

  Next, a third structure in the dye-sensitized solar cell of the present invention will be described with reference to FIG. FIG. 5 shows a cross-sectional structure of the dye-sensitized solar cell of the present invention.

 The basic components of the dye-sensitized solar cell in the third embodiment are the first substrate 10 and the second substrate 20 made of a transparent film material, the first thin film electrode 11 made of a metal film, and the metal oxide transparent. The electrode comprises a second thin film electrode 21, a semiconductor layer 30 mainly composed of titanium dioxide fine particles, a dye 31, an insulating spacer 40 having a function of joining two substrates, and an electrolyte layer 50. This is the same as the second embodiment. Further, in this embodiment, a conductive spacer 41 is provided.

 In the dye-sensitized solar cell in the present embodiment, conductive spacers 41 that are in contact with the upper and lower substrates are provided on the outer peripheral portion of the insulating spacer 40. The conductive spacer 41 is conductive as a solid by kneading conductive particles such as carbon and silver in a synthetic resin or rubber-based material. However, the first thin film electrode 11 is not formed in a portion where the conductive spacer 41 is provided so as not to contact the conductive spacer 41.

 A second through hole 62 is formed in the first substrate 10 where the conductive spacer 41 is in contact with the first substrate 10. Since the second through hole 62 is formed so as to reach the conductive spacer 41, the conductive spacer 41 is exposed on the bottom surface of the second through hole 62 and serves as the second connection electrode 66. Since the conductive spacer 41 is in electrical contact with the second thin film electrode 21, the second connection electrode 66 can be electrically connected to the second thin film electrode 21.

 Further, a first through hole 61 reaching the first thin film electrode 11 is formed at another location on the first substrate 10. Although a part of the first thin film electrode 11 is exposed by the first through hole 61, the exposed part is a first connection electrode 65. However, the first through hole 61 is desirably formed in a portion where the insulating spacer 40 is provided in order to maintain the strength of the first connection electrode 65. The first through hole 61 is basically the same as the through hole 60 described in the previous embodiment.

 By adopting the above configuration, in the dye-sensitized solar cell of the present invention, the connection surfaces of the first connection electrode 65 and the second connection electrode 66 for connecting to the outside are present in the same plane. become. From this, in the dye-sensitized solar cell of the present invention, when an external circuit is arranged facing the first substrate 10, direct connection can be made very easily.

 In addition, as illustrated in FIG. 6, the auxiliary electrode 12 may be provided between the conductive spacer 41 and the first substrate 10. The auxiliary electrode 12 is formed on the surface of the first substrate 10 in the same plane as the first thin film electrode 11. The auxiliary electrode 12 is made of a metal thin film, but is basically the same material as the first thin film electrode 11. Since the auxiliary electrode 12 is a metal film, it is possible to reduce the contact resistance rather than taking external contact directly from the conductive spacer 41.

 In addition, although the effects of the present invention can be obtained with the structure shown in FIG. 5 or FIG. 6, electrode pads may be formed on the connection electrodes of the upper and lower substrates. The structure is shown in FIG. A first electrode pad 81 and a second electrode pad 82 made of conductive resin are formed so as to be in electrical contact with the first connection electrode 65 and the second connection electrode 66. As the conductive resin, an epoxy resin, an acrylic resin, or a silicone resin in which conductive particles such as carbon and silver are kneaded is used. The presence of the electrode pad does not directly contact the thin film electrode when connected to the outside, so that there is no risk of film damage and the reliability is increased. Moreover, since it can be made to protrude from the surface of the 1st board | substrate 10, the contact from the outside becomes easy.

 Further, as shown in FIG. 8, the conductive spacer 41 may not only be disposed on the outer periphery of the insulating spacer 40 but also enter the inside. FIG. 9 shows this structure in a plan view. As is apparent from the drawings, the insulating spacer 40 can be disposed up to the outermost periphery by adopting such a structure. This prevents the substrate from being free on the outer periphery of the substrate as in the prior art, and the film surfaces of the first thin film electrode 11 and the second thin film electrode 21 are not exposed at all. Reliability can be improved. Further, although not shown in the figure, it is more effective to seal the side surface of the substrate with an insulating adhesive or the like.

 Then, the manufacturing method of the dye-sensitized solar cell of the 3rd Example is described. First, a film-like first substrate 10 is prepared, and a platinum thin film is formed using a sputtering method to form a first thin film electrode 11. Titanium, nickel, chromium, an aluminum film, or the like may be formed as a base layer in order to maintain close contact with the substrate or reduce film resistance. When the first thin film electrode 11 is formed, no thin film is formed on the portion in contact with the conductive spacer 41. Alternatively, the auxiliary electrode 12 is formed of the same material as the first thin film electrode 11 at the same time by being electrically separated from the portion to be the first thin film electrode 11.

 The patterned first thin film electrode 11 and auxiliary electrode 12 can be formed by using a metal plate mask that has been processed in advance into the shape of the thin film to be formed, and performing patterning during film formation. Alternatively, a thin film can be formed on almost the entire surface of the first substrate 10, and a pattern can be formed by an etching method using photolithography. Although not shown, a minute injection hole for injecting the electrolyte later is formed in the first substrate 10.

 Similarly, a film-like second substrate 20 is prepared, and an ITO thin film is also formed by using the sputtering method to form the second thin film electrode 21. Subsequently, a paste in which fine particles of titanium dioxide are dispersed in an organic solvent such as polyethylene glycol, alcohol, and acetone or water is prepared, and printed on the second thin film electrode 21 in a desired shape using a squeegee method. After the solvent is evaporated to some extent at room temperature, the paste is baked in an electric furnace to form the semiconductor layer 30. At this time, the titanium dioxide particles are bonded to each other to lower the overall resistance.

 Further, a dye solution in which the dye 31 is dissolved in an organic solvent is prepared, and the second substrate 20 is immersed in the dye solution, and the dye 31 is adsorbed on the surface of the titanium dioxide particles as the semiconductor layer 30. The substrate with the dye 31 is completed by heating or natural drying after removing from the solution.

 A hot-melt type adhesive is processed into a desired shape and disposed on the outer periphery of the semiconductor layer 30 formed on the second substrate 20. At the same time, an electrically conductive hot melt adhesive is also disposed at a place where the second connection electrode 66 is to be formed. The first substrate 10 previously prepared is opposed to the second substrate 20 and heated while applying pressure. When the hot melt material is melted, it is compatible with the upper and lower substrates. When the hot melt material is returned to room temperature, it is solidified again to become the insulating spacer 40 and the conductive spacer 41, and the bonding is completed.

 For bonding, a thermosetting or photocurable adhesive may be prepared as the material of the insulating spacer 40 and disposed on the outer periphery of the semiconductor layer 30. As the material of the conductive spacer 41, it is also possible to use a thermosetting or photocurable adhesive in which conductive particles are kneaded. These are placed on the first substrate 10 or the second substrate 20 by a process such as printing or dispensing, and are cured and fixed by heating or irradiating light after the two substrates are combined.

 Subsequently, a laser beam is irradiated from the lower surface of the first substrate 10 to dissolve and remove a part of the first substrate 10 to form the first through hole 61. The first through hole 61 is formed at the position of the insulating spacer 40 previously formed, but is preferably smaller than the width of the insulating spacer 40. Thereby, the exposed first thin film electrode 11 portion becomes the first connection electrode 65.

 Similarly, the second through hole 62 is formed by laser irradiation. The second through hole 62 is formed in a portion where the conductive spacer 41 is provided, but is preferably smaller than the width of the conductive spacer 41. The second through hole 62 is processed until the surface of the conductive spacer 41 or the surface of the auxiliary electrode 12 is exposed, and this exposed surface becomes the second connection electrode 66. Here, the first through hole 61 and the second through hole 62 may be formed in either order.

 Further, if necessary, the first electrode pad 81 and the second electrode pad 82 are formed on the first connection electrode 65 and the second connection electrode 66 by using a dispensing method or a printing method. The conductive resin to be the electrode pad is completed by placing the stock solution at a predetermined location and then curing it by heating or ultraviolet irradiation.

 Finally, the electrolyte layer 50 is formed by injecting an electrolytic solution into the internal space from a previously formed injection hole of the first substrate 10 using a syringe or the like. Thereafter, a hot melt agent is placed on the injection hole and sealed by reheating. The dye-sensitized solar cell of the present invention is completed through the above steps.

 Since the first through hole 61 and the second through hole 62 that have come out in the above description are formed in the first substrate 10 in the drawing, they are literally in the shape of holes, but are formed in the outer peripheral portion. You may do it. In this case, the shape is not a hole but a notch, but if the insulating spacer 40 or the conductive spacer 41 is provided on the hole, a necessary function can be achieved. Further, when the first connection electrode 65 and the second connection electrode 66 are formed adjacent to each other, the first through hole 61 and the second through hole 62 can be connected to form one.

In each of the embodiments described above, the through hole 60 or the first through hole and the second through hole are formed in the first substrate 10. However, the through hole can be formed in the second substrate 20. In this case, electrical contact with the outside is performed from the second substrate side. However, when the second through hole is provided in the second substrate 20, the second thin film electrode 21 is patterned instead of patterning the first thin film electrode 11.

  Subsequently, a configuration when the dye-sensitized solar cell of the present invention is used as a power generation cell for a wristwatch will be described. FIG. 10 shows a cross-sectional view of a wristwatch equipped with the dye-sensitized solar cell of the present invention.

  FIG. 10 shows an analog wristwatch, in which a display board 104, a dye-sensitized solar cell 105, a movement 106, and a circuit board 107 are mounted in a space formed by a case 101, a windshield 102, and a back cover 103. Yes. The circuit board 107 is basically integrated with the movement 106, and the movement 106 includes mechanical parts such as gears, a motor, a vibrator, a secondary battery, and the like.

  External light passes through the transparent windshield 102 and reaches the display panel 104. However, since the display panel 104 is translucent, part of the light reaches the lower part thereof. Since the dye-sensitized solar cell 105 is disposed immediately below the display panel 104, the dye-sensitized solar cell 105 can generate electric power with the reached light. Since light is incident through the windshield glass 102, the dye-sensitized solar cell 105 is arranged so that the second substrate 20, which is a transparent substrate, faces the upper side, that is, the windshield glass 102 side.

  The energy generated by the dye-sensitized solar cell 105 is supplied to the circuit side, and the circuit board 107 for that purpose is disposed so as to be immediately below the dye-sensitized solar cell 105. As described with reference to FIG. 1, the dye-sensitized solar cell 105 of the present invention has the first connection electrode 65 and the second connection electrode 66 facing downward, so that it faces the circuit board 107 in the immediate vicinity. it can. By providing the circuit board 107 with the conductive terminal 108 in advance, the conductive terminal 108 can be in direct contact with the first connection electrode 65 and the second connection electrode 66. You can connect.

  A detailed connection state by the conductive terminal 108 is shown in FIG. In FIG. 11, the dye-sensitized solar cell uses the insulating spacer 40 as a reinforcing layer as shown in FIG. 4, and the first connection electrode 65 and the second connection electrode 66 are close to each other. Arranged to come to. As is clear from FIG. 11, in the dye-sensitized solar cell of the present invention, it can be seen that the connection electrode and the external circuit of the solar cell can be easily connected by the conductive terminal 108. The conductive terminal 108 may be made of an elastic member such as a coil spring, a leaf spring, or a spring bar having a spring in a stretchable metal cylinder so as to ensure contact.

  FIG. 12 shows a detailed connection state by the conductive terminal 108 when the dye-sensitized solar cell in Example 3 is used. As can be seen from the figure, by providing the second connection electrode 66 on the first substrate 10 as well, the conductive terminals 108 having the same length can be used, and the alignment of the connection and the like can be further simplified.

  The electrical energy sent from the dye-sensitized solar cell 105 to the circuit board 107 is stored in the secondary battery, and the wristwatch can be continuously driven by using the energy of the secondary battery.

 In the wristwatch provided with the dye-sensitized solar cell of the present invention, the dye-sensitized solar cell 105 is installed under the display panel 104. However, by printing characters or the like on the dye-sensitized solar cell 105 to be used, it is possible to have a function as the display plate 104. In that case, it is not necessary to provide the display plate 104 with another material.

10 first substrate 11 first thin film electrode 12 auxiliary electrode 20 second substrate 21 second thin film electrode 25 lead wire 30 semiconductor layer 31 dye 40 insulating spacer 41 conductive spacer 50 electrolyte layer 60 through hole 61 first through hole 62 second through Hole 63 Notch 65 First connection electrode 66 Second connection electrode 70 Reinforcing layer 81 First electrode pad 82 Second electrode pad 101 Case 102 Windshield 103 Back cover 104 Display board 105 Dye-sensitized solar cell 106 Movement 107 Circuit board 108 Conductive terminal

Claims (11)

 A first substrate having a first thin film electrode; a second substrate having a second thin film electrode; a semiconductor layer in contact with either the first thin film electrode or the second thin film electrode and adsorbing a dye; A space surrounded by the first thin film electrode, the second thin film electrode, the second thin film electrode, and the insulating spacer disposed between the first thin film electrode and the second thin film electrode. A dye-sensitized solar cell having a formed electrolyte layer, wherein the first substrate has a through hole reaching the first thin film electrode.   The surface of the first thin film electrode exposed inside the through hole serves as a first connection electrode, and a reinforcing layer is provided on the first thin film electrode, which is the opposite surface of the first connection electrode. Item 2. The dye-sensitized solar cell according to Item 1.   The dye-sensitized solar cell according to claim 2, wherein the insulating spacer also functions as the reinforcing layer.  The said 2nd board | substrate has a part extended from the outer periphery of the said 1st board | substrate, It has a 2nd connection electrode in the extended part, The Claim 1 characterized by the above-mentioned. Dye-sensitized solar cell.  4. The conductive spacer according to claim 1, further comprising a conductive spacer that is in electrical contact with the second thin film electrode and reaches the first substrate while being insulated from the first thin film electrode. The dye-sensitized solar cell according to Item.  6. The dye-sensitized solar cell according to claim 5, further comprising an auxiliary electrode between the conductive spacer and the first substrate.  A first through hole is provided on the opposite surface of the first substrate with which the reinforcing layer or the insulating spacer comes into contact, a first connection electrode is exposed inside the first through hole, and the conductive layer is further conductive. 7. The second through hole is provided on the opposite surface of the first substrate with which the spacer contacts, and the second connection electrode is exposed inside the second through hole. 2. A dye-sensitized solar cell according to 1.  The dye-sensitized solar cell according to claim 2, 3 or 7, further comprising a first electrode pad that is in electrical contact with the first connection electrode inside the through hole.  The dye-sensitized solar cell according to claim 4 or 7, further comprising a second electrode pad that is in electrical contact with the second connection electrode.   A dye sensitizing device according to any one of claims 1 to 9, wherein the display plate, the movement, and the circuit board are mounted in a space formed by a case, a windshield, and a back cover. A solar cell is mounted between the display plate and the movement so that the second substrate faces the display plate, and the first connection electrode and the second connection electrode are opposed to the circuit board, A wristwatch comprising a dye-sensitized solar cell, wherein the wristwatch is electrically connected using a conductive terminal.   The wristwatch provided with the dye-sensitized solar cell according to claim 10, wherein the conductive terminal is provided on the circuit board in advance.

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