JP4396574B2 - Dye-sensitized solar cell and method for producing the same - Google Patents

Description

  The present invention relates to a dye-sensitized solar cell and a method for producing the same.

  In recent years, batteries called dye-sensitized solar cells have been developed. The dye-sensitized solar cell was developed in 1991 by Gretzer et al. At the University of Lausanne in Switzerland and is also called a Gretzell cell. This is because a light electrode having a light-transmitting substrate, a light-transmitting conductive layer laminated on the substrate, and a dye that emits electrons upon receiving light, and facing the light electrode at a predetermined interval. And a conductive counter electrode, and a fluid electrolyte layer disposed between the photoelectrode and the counter electrode. In general, a ruthenium complex is used as the dye, and an electrolytic solution containing iodine is used as the electrolyte layer. In the dye-sensitized solar cell described above, the phenomenon that electrons are emitted when the dye is excited by absorbing sunlight, and the holes that remain in the dye made of ruthenium complex oxidize iodine in the electrolyte layer are utilized. It has been reported in the literature.

In addition, according to the published patent gazette related to Patent Document 1, the photoelectrode and the counter electrode are combined so as to overlap each other, and a sealing solid material coated with a sealing resin is interposed between the photoelectrode and the counter electrode. Technology is disclosed. According to the technology according to this publication, an epoxy resin or a silicone resin is used as a sealing resin.
JP 2000-173680 A

  It is an object of the present invention to provide a dye-sensitized solar cell and a method for manufacturing the same that can ensure good sealing performance in a battery seal part over a long period when a plurality of counter electrodes are arranged in parallel. To do.

(1) The dye-sensitized solar cell of the present invention that solves the above-mentioned problems is a photoelectrode having a light- transmitting substrate, a transparent conductive layer, an N-type semiconductor layer, and a dye,
A counter electrode facing the photoelectrode at a predetermined interval and having conductivity;
An electrolyte layer enclosed between the photoelectrode and the counter electrode;
In a dye-sensitized solar cell having a battery seal part that seals against the electrolyte layer,
A plurality of the counter electrode, the electrolyte layer, and the transparent conductive layer are arranged in series,
It has a microspherical filler that regulates the distance between the photoelectrode and the counter electrode, and has an intermediate seal portion that covers and covers between the adjacent counter electrodes.

  Moreover, it is preferable that the battery seal portion covers a surface of the counter electrode on the side opposite to the photoelectrode.

The intermediate seal portion is preferably made of a thermosetting or ultraviolet curable polyisobutylene material.

  In order to ensure electrical insulation between the photoelectrode and the counter electrode or to secure a storage chamber for storing the electrolytic solution, a filler that forms a microsphere can be added to the intermediate seal portion.

(2) A method for manufacturing a dye-sensitized solar cell according to the present invention includes a light electrode having a light-transmitting substrate, a transparent conductive layer, an N-type semiconductor layer, and a dye, A battery element having a conductive counter electrode facing each other with a gap therebetween is prepared,
Preparing a battery seal part having a base film and a coating material based on a polyisobutylene resin applied to one side of the base film;
By carrying out the step of bonding the battery seal portion to the battery element and curing the coating material with the coating material of the battery seal portion facing the counter electrode of the battery element,
A photoelectrode having a light-transmitting substrate, a transparent conductive layer, an N-type semiconductor layer, and a dye;
A counter electrode facing the photoelectrode at a predetermined interval and having conductivity;
An electrolyte layer enclosed between the photoelectrode and the counter electrode;
In a dye-sensitized solar cell having a battery seal part that seals against the electrolyte layer,
A plurality of the counter electrode, the electrolyte layer, and the transparent conductive layer are arranged in series,
A dye-sensitized solar cell is characterized by having an intermediate seal portion that fills and covers the adjacent counter electrodes .

  According to the method for producing a dye-sensitized solar cell according to the present invention, the battery seal portion before being bonded to the battery element is mainly formed of a base film and a polyisobutylene-based resin laminated on one side of the base film. It has the coating material used as a seal part. Thereafter, in a state where the coating material of the battery seal portion is opposed to the counter electrode of the battery element, the battery seal portion is bonded to the battery element and the coating material is cured. Curing means to solidify the coating material. Therefore, the battery seal portion in the cured state has elasticity necessary for sealing.

  By the way, the manufacturing method which adhere | attaches the coating material used as the main seal part which makes a polyisobutylene-type resin a base material directly on a battery element, without using a base film, and can seal is also considered. However, in this case, the amount of the coating material may vary depending on the part. In this regard, according to the method for producing a dye-sensitized solar cell according to the present invention, since a coating material based on a polyisobutylene resin is applied in advance to one side of a base film, a polyisobutylene resin is used as a substrate. This is advantageous for averaging the amount of the coating material. As a result, it is advantageous to suppress an excessive amount of the coating material serving as the main seal portion, and it is advantageous to suppress entry of the coating material component into the battery.

  In addition, the battery seal part formed using the polyisobutylene-based resin as a base material has high adhesion to a counterpart material such as a transparent conductive layer or glass. When higher adhesion is required, primer treatment using a silane coupling agent or the like can be performed on the base material of the battery seal portion.

  ADVANTAGE OF THE INVENTION According to this invention, the battery suitable when the some counter electrode is arranged in parallel can be provided.

  According to the technology relating to the dye-sensitized solar cell according to the present invention, a configuration is adopted in which a plurality of counter electrodes are arranged in parallel with a common light electrode at a predetermined interval. The battery seal part can adopt a form having a base film and a main seal part based on a polyisobutylene resin laminated on one side of the base film. In this case, it has an intermediate | middle seal part which coat | covers between adjacent counter electrodes. Furthermore, the battery seal part can employ | adopt the form which coat | covers the surface on the opposite side to a photoelectrode among each counter electrode. This is suitable when a plurality of counter electrodes are arranged in parallel.

  The battery seal portion can be formed using a polyisobutylene resin as a base material. In this case, it may be formed of only polyisobutylene or a copolymer. A filler such as a glass filler may be blended in the polyisobutylene resin as necessary.

  An electrolyte solution can be used as the electrolyte layer. An electrolytic solution in which an electrolyte substance is dissolved in a solvent can be employed. As a solvent for the electrolytic solution, a nitrile compound such as acetonitrile, methoxyacetonitrile, propylonitrile, a solvent such as ethylene carbonate, propylene carbonate, butylene carbonate, γ-butyrolactone, or a mixed solvent thereof can be employed. . The electrolyte layer may be a solid electrolyte. Examples of the solid electrolyte include gels of the above electrolytic solutions, polymer electrolytes having iodine ion conductivity, inorganic electrolytes having iodine ion conductivity, and the like. The battery seal portion has a purpose of preventing leakage of an electrolyte layer such as an electrolyte solution inside the dye-sensitized solar cell and a purpose of preventing oxygen, water vapor, and the like from being mixed from the outside.

The intermediate seal portion, in order to ensure electrical insulation between the optical electrode and the counter electrode, or, for ensuring a storage chamber to store an electrolyte solution, the filler forming the microspheres (e.g., glass filler) is Ru is added .
Further, in addition to the addition of fillers that form microspheres , the intermediate seal portion may be provided by applying an isobutylene resin.

  According to the technique relating to the dye-sensitized solar cell according to the present invention, a mode in which an injection port for injecting an electrolyte is provided can be employed. In this case, the battery seal part is composed of a main seal part formed using a thermosetting polyisobutylene resin surrounding the electrolyte layer as a base material, and an ultraviolet curable polyisobutylene resin sealing the inlet. It is possible to adopt a form having a secondary seal portion formed as:

(Appendix)
Below, the knowledge about a dye-sensitized solar cell and its manufacturing method, and a suitable structure are illustrated.

  Conventionally, when the battery seal portion is an epoxy resin, there is a problem in long-term corrosion resistance. In particular, good sealability cannot be ensured for a long period of time at the portion that is in direct contact with the electrolyte. This is because the degree of crosslinking decreases due to the reaction between the double bond portion in the resin skeleton and iodine in the electrolyte solution, and the battery seal portion swells due to the electrolyte solution. Further, when the battery seal portion is made of a silicone resin, there is a problem in the sealing performance of the electrolyte because it is easily swelled by the organic solvent in the electrolyte.

  As a countermeasure, according to the technique disclosed in JP 2000-173680 described above, a solid material for sealing such as glass having high corrosion resistance is disposed between the photoelectrode and the counter electrode and sealed. In addition, since the above-described epoxy resin or the like is used for the adhesive layer between the solid material, the photoelectrode, and the counter electrode, the reliability in the sealing performance of the battery seal portion is not always sufficient.

  (1) In order to solve such a problem, the present inventor has been diligently developing a dye-sensitized solar cell. Then, attention was paid to the fact that the electrolyte layer in the dye-sensitized solar cell contains a halogen such as iodine. Halogen such as iodine is present in an ionized state in the electrolyte layer and has a property of easily reacting with a double bond portion in an organic substance. For this reason, a resin having a double bond in the skeleton such as an epoxy resin causes a reduction in the degree of crosslinking, and has low reliability against long-term electrolyte layer leakage.

  As a result of studying the swelling property, adhesion, etc. of the battery seal portion of various materials with respect to the electrolyte layer, the polyisobutylene-based resin has been used as a material having high durability for the electrolyte layer containing a halogen such as iodine. I found it appropriate. The polyisobutylene-based resin is presumed to have no double bond in its basic skeleton, so that the reaction with a halogen such as iodine contained in the electrolyte layer can be suppressed.

(2) That is, the dye-sensitized solar cell includes a light-transmitting substrate, a transparent conductive layer, an N-type semiconductor layer, and a photoelectrode having a dye.
A counter electrode facing the photoelectrode at a predetermined interval and having conductivity;
An electrolyte layer encapsulated between a photoelectrode and the counter electrode;
In a dye-sensitized solar cell having a battery seal part that seals against an electrolyte layer,
The electrolyte layer preferably contains halogen, and the battery seal portion is preferably formed using a polyisobutylene resin as a base material.

  According to this dye-sensitized solar cell, the electrolyte layer contains a halogen such as iodine or bromine. The battery seal portion is formed using a polyisobutylene resin as a base material. The polyisobutylene resin has high durability against halogens such as iodine and bromine. This is presumed to be because the basic skeleton does not have a double bond, so that the reaction with a halogen such as iodine can be suppressed. Furthermore, the polyisobutylene resin is excellent in barrier properties against moisture and gas. Adhesion to the transparent conductive layer and glass plate, which are the main constituent elements of the photoelectrode and counter electrode, is also high.

(3) The dye-sensitized solar cell faces a light-transmitting substrate, a transparent conductive layer, an N-type semiconductor layer, a dye, and a photoelectrode, with a predetermined distance from the photoelectrode. While preparing a battery element having a counter electrode having conductivity,
Preparing a battery seal part having a base film and a coating material based on a polyisobutylene resin applied to one side of the base film;
The coating material of the cell sealing portion while being opposed to the counter electrode of the battery element, by implementing a step of curing the coating material with bonding the cell sealing part to the battery element, the color Motozo sensitized solar cell It is desirable to be characterized by manufacturing.

  According to this method for producing a dye-sensitized solar cell, the battery seal portion before being bonded to the battery element is formed of a base film, a main seal portion that is laminated on one side of the base film and has a polyisobutylene resin as a base material. It has the coating material which becomes. Thereafter, in a state where the coating material of the battery seal portion is opposed to the counter electrode of the battery element, the battery seal portion is bonded to the battery element and the coating material is cured. Curing means to solidify the coating material. Therefore, the battery seal portion in the cured state has elasticity necessary for sealing.

  By the way, the manufacturing method which adhere | attaches the coating material used as the main seal part which makes a polyisobutylene-type resin a base material directly on a battery element, without using a base film, and can seal is also considered. However, in this case, the amount of the coating material may vary depending on the part. According to this method for producing a dye-sensitized solar cell, since a coating material based on a polyisobutylene resin is applied in advance to one surface of a base film, the coating based on a polyisobutylene resin is used. This is advantageous for averaging the amount of material. As a result, it is advantageous to suppress an excessive amount of the coating material serving as the main seal portion, and it is advantageous to suppress entry of the coating material component into the battery.

  In addition, the battery seal part formed using the polyisobutylene-based resin as a base material has high adhesion to a counterpart material such as a transparent conductive layer or glass. When higher adhesion is required, primer treatment using a silane coupling agent or the like can be performed on the base material of the battery seal portion.

  According to such a dye-sensitized solar cell and manufacturing method, the reliability for preventing leakage of the electrolyte layer can be improved. Therefore, the conversion efficiency in the solar cell can be maintained well over a long period of time. As a result, the environmental conditions in which the dye-sensitized solar cell can be used are expanded, and the application can be expected to expand.

  In addition, according to the method for manufacturing a dye-sensitized solar cell, an application material having a polyisobutylene resin as a base material may be applied to the base film in an amount necessary for adhesion. For this reason, the amount of the coating material applied to the base film can be minimized. For this reason, it becomes advantageous for suppressing that the excessive component of the coating material penetrates into the solar cell from the surface of the counter electrode layer or the like. Therefore, it is advantageous to suppress a decrease in the performance of the solar cell.

(First embodiment)
A first embodiment according to the present invention will be described. FIG. 1 shows a typical configuration of a dye-sensitized solar cell according to the first embodiment. As shown in FIG. 1, this solar cell has a photoelectrode 1, a counter electrode 2, an electrolyte layer 3, and a battery seal portion 4. The light electrode 1 has a light incident surface 10 and a mounting surface 11 facing each other and a light transmitting glass substrate 13, and a mounting surface 11 on one side of the substrate 13 opposite to the light incident surface 10. A transparent conductive layer 15 having optical transparency laminated on the substrate, a porous N-type semiconductor layer 16 (titanium oxide layer) laminated on the transparent conductive layer 15, and a dye carried on the N-type semiconductor layer 16 18. The transparent conductive layer 15 is formed of an SnO ₂ film doped with F or Sb or an ITO film. The dye 18 is a ruthenium complex and has an electron emission property associated with light reception.

  The counter electrode 2 faces the photoelectrode 1 with a predetermined interval. The counter electrode 2 has a mounting surface 21 and a light-transmitting glass substrate 23, a conductive layer 25 laminated on the mounting surface 21 of the substrate 23, and a counter electrode catalyst 26 supported on the conductive layer 25. . Since the conductive layer 25 on the counter electrode 2 side is not required to transmit light, transparency is not particularly required. Therefore, the conductive layer 25 on the counter electrode 2 side can be formed of a metal having high corrosion resistance with respect to iodine and having conductivity. For example, titanium, tantalum, niobium, tungsten, platinum, or the like can be used. However, in order to make the parts common, in this embodiment, the photoelectrode 1 and the counter electrode 2 are the same.

  The electrolyte layer 3 is disposed between the photoelectrode 1 and the counter electrode 2 and is formed of a fluid electrolyte. The electrolytic solution is obtained by dissolving an electrolyte in an organic solvent. As the electrolyte, iodine which is a halogen is adopted. Iodine exists as an ion. The counter electrode 2 is provided with an injection port 9 for injecting an electrolytic solution.

  The battery seal portion 4 seals the electrolyte layer 3. The battery seal portion 4 is interposed between the photoelectrode 1 and the counter electrode 2 and has a main seal portion 5 having a frame shape formed using a thermosetting polyisobutylene resin as a base material, and an ultraviolet ray that blocks the injection port 9. The secondary seal portion 6 is formed with a curable polyisobutylene resin as a base material. The main seal portion 5 seals the periphery of the electrolyte layer 3.

  In manufacturing the solar cell described above, a coating material based on a thermosetting polyisobutylene resin constituting the main seal portion 5 is disposed on at least one of the photoelectrode 1 and the counter electrode 2. Thereafter, the photoelectrode 1 and the counter electrode 2 are bonded so as to face each other. Thereafter, the thermosetting polyisobutylene resin is thermally cured by heat treatment to form the main seal portion 5. Thereafter, an electrolytic solution is injected from the inlet 9 of the counter electrode 2. Thereafter, a coating material having an ultraviolet curable polyisobutylene resin as a base material is disposed at the injection port 9 of the counter electrode 2, and this is irradiated with ultraviolet rays to be cured by ultraviolet rays, thereby forming the sub seal portion 6. In the ultraviolet curable polyisobutylene resin, an adhesive force can be instantaneously ensured by irradiation with ultraviolet rays, so that the electrolytic solution between the photoelectrode 1 and the counter electrode 2 can be quickly sealed.

  When using the dye-sensitized solar cell described above, power is generated when light is incident on the light incident surface 10 of the photoelectrode 1. As a principle of power generation, electrons generated on the side of the N-type semiconductor layer 16 on the side of the photoelectrode 1 based on the dye 18 due to light incidence move to the counter electrode 2 side through the lead wire of the external circuit, It is generally considered that electricity is generated based on the fact that electrons are carried from the counter electrode 2 to the N-type semiconductor layer 16 by the oxidation-reduction reaction of iodine contained in the electrolyte solution of the electrolyte layer 3. For this reason, in order to ensure the durability of the dye-sensitized solar cell, it is essential to prevent leakage of the electrolyte solution constituting the electrolyte layer 3.

  According to the present embodiment, since the battery seal portion 4 is formed using a polyisobutylene resin as a base material, durability against iodine contained in the electrolyte solution of the electrolyte layer 3 is ensured, and the battery seal portion 4 Reliability is improved. This has been confirmed by testing. It is presumed that the polyisobutylene-based resin does not have a double bond in its basic skeleton, and therefore can suppress reaction with halogen ions such as iodine ions contained in the electrolyte layer 3.

  In particular, according to this embodiment, the battery seal portion 4 has a frame shape formed by using a thermosetting polyisobutylene resin as a base material together with an intermediate seal portion 5w interposed between the photoelectrode 1 and the counter electrode 2. The main seal portion 5 is formed, and the sub seal portion 6 is formed by using an ultraviolet curable polyisobutylene resin that closes the injection port 9 as a base material. Since the main seal portion 5 is cured before injecting the electrolytic solution, there is little demand for instantaneous curing, and therefore a thermosetting type is used. Since the secondary seal portion 6 is cured after injecting the electrolytic solution, there is a strong demand for instantaneous curing in order to prevent leakage of the electrolytic solution, so an ultraviolet curing type is used. For this reason, it is advantageous for preventing leakage of the electrolyte layer 3 accommodated between the photoelectrode 1 and the counter electrode 2 and suppressing the entry of gas such as air into the electrolyte layer 3.

(First test example)
A dye-sensitized solar cell according to the first example was prepared as follows. First, a method for creating the photoelectrode 1 will be described. Transparent glass was used as the substrate 13 on the photoelectrode 1 side. The size of the transparent glass was 15 mm × 25 mm × 1.1 mm. The transparent conductive layer 15 laminated on the substrate 13 on the photoelectrode 1 side was a SnO ₂ film doped with F and having a surface resistivity of 10Ω / □. The surface resistivity is based on JIS-W7202. A titanium oxide paste 16c to be an N-type semiconductor layer 16 was laminated on the mounting surface 11 which is one side of the substrate 13 on the side of the photoelectrode 1 by screen printing a titanium oxide paste and baking at 450 ° C. The laminated titanium oxide layer 16c had an electrode area size of 6 mm × 20 mm and a thickness of 10 μm. The substrate 13 on the side of the photoelectrode 1 is immersed in an ethanol solution of ruthenium complex for a predetermined time (24 hours), thereby adsorbing the ruthenium complex functioning as the dye 18 on the surface of the titanium oxide layer 16c. Created.

  Next, creation of the counter electrode 2 will be described. As the substrate 23 on the counter electrode 2 side, the same transparent glass plate as that on the photoelectrode 1 side was used. A conductive layer 25 is laminated on the mounting surface 21 of the substrate 23. In order to inject the electrolytic solution, an injection port 9 having a diameter of about 1 mm was formed on the substrate of the counter electrode 2 by drilling. A Pt solution is applied to the surface of the conductive layer 25 on which the substrate 23 on the counter electrode 2 side is laminated by spin coating and baked at 400 ° C., thereby supporting Pt catalyst particles functioning as the counter electrode catalyst 26. A counter electrode 2 was formed.

  Using the thus formed photoelectrode 1 and counter electrode 2, a main seal is formed by a dispenser at a position of about 2 mm outside the periphery of the N-type semiconductor layer 16 formed of the titanium oxide layer 16 c of the photoelectrode 1. A thermosetting polyisobutylene resin coating material to be part 5 was applied. The polyisobutylene resin used as the main seal portion 5 has a particle diameter of 50 μm in order to ensure electrical insulation between the photoelectrode 1 and the counter electrode 2 or to secure a storage chamber 35 for storing the electrolytic solution. A filler (for example, a glass filler) having a microsphere shape was added. Thereafter, the photoelectrode 1 and the counter electrode 2 were bonded together. In this case, after the photoelectrode 1 and the counter electrode 2 were bonded together, the polyisobutylene resin was thermally cured by heating at 100 ° C. for 30 minutes, and the main seal portion 5 was formed.

  Next, in the state where the injection port 9 formed in the counter electrode 2 is immersed in the electrolytic solution, the inside of the storage chamber 35 between the photoelectrode 1 and the counter electrode 2 is removed by a vacuuming operation so that the electrolytic solution does not boil. Then, the electrolytic solution was injected into the storage chamber 35 by returning to atmospheric pressure. The electrolyte used was a solution in which iodine and lithium iodide were dissolved in propylene carbonate, which is an organic solvent.

  After injecting the electrolytic solution into the storage chamber 35 as described above, a coating material of an ultraviolet curable polyisobutylene resin is applied to the injection port 9, and the spot is irradiated with ultraviolet rays, whereby the polyisobutylene resin is converted into ultraviolet rays. The secondary seal part 6 was formed by curing, and the electrolytic solution in the storage chamber 35 was sealed.

  About the solar cell produced as mentioned above, the high temperature leaving test which is left to stand at 85 degreeC was performed for 100 hours, and the low temperature standing test to be left to -40 degreeC was done for 100 hours. Even after the test, electrolyte leakage from the main seal portion 5 and the sub seal portion 6 did not occur. Since the glass transition temperature of the polyisobutylene resin is lower than −40 ° C., the necessary elasticity for sealing the main seal portion 5 and the sub seal portion 6 was ensured even in the low temperature test.

(Second embodiment)
A second embodiment according to the present invention will be described. 2 and 3 show a typical configuration of the dye-sensitized solar cell according to the second embodiment. As shown in FIG. 2, this solar cell has a photoelectrode 1, a counter electrode 2B, a separator layer 7, an electrolyte layer 3, and a battery seal portion 4B. The photoelectrode 1 has a light incident surface 10 and a mounting surface 11 facing each other and has a light-transmitting glass substrate 13, and a light-transmitting transparent conductive layer laminated on the mounting surface 11 of the substrate 13. 15, a porous N-type semiconductor layer 16 (titanium oxide layer) laminated on the transparent conductive layer 15, and a dye 18 carried on the N-type semiconductor layer 16. The transparent conductive layer 15 has a groove 15m, and is formed of an SnO ₂ film doped with F or Sb, or an ITO film. The dye 18 is a ruthenium complex. As shown in FIG. 2, a plurality of counter electrodes 2 </ b> B are arranged in series with respect to a common single light electrode 1. The counter electrode 2B is formed of a carbon film and has conductivity, durability against an electrolytic solution, and catalytic properties. Since no light is transmitted through the counter electrode 2B, transparency is not particularly required. A porous separator layer 7 is interposed between the photoelectrode 1 and the counter electrode 2B. The separator layer 7 blocks direct electrical conductivity between the photoelectrode 1 and the counter electrode 2B.

  The electrolyte layer 3 is disposed between the photoelectrode 1 and the counter electrode 2B, and is formed of an electrolytic solution having fluidity. An inlet 9 for injecting an electrolytic solution is provided on the end side of the solar cell according to this example. The battery seal portion 4B seals the electrolyte layer 3. The battery seal portion 4B is interposed between the photoelectrode 1 and the counter electrode 2B, and seals the main seal portion 5B formed using a thermosetting polyisobutylene resin as a base material, the inlet 9, and an ultraviolet curable type. It is formed with the sub seal part 6B formed using polyisobutylene resin as a base material. As shown in FIG. 2, the main seal portion 5B seals the periphery of the electrolyte layer 3, an intermediate seal portion 5w that covers and covers the adjacent counter electrodes 2B, and the photoelectrode 1 of each counter electrode 2B. The outer surface seal portion 5x that covers the surface opposite to the outer surface and the outer edge seal portion 5y that seals the outer edge of the solar cell.

  According to the present embodiment, as in the first embodiment, since the battery seal portion 4B is formed using a polyisobutylene resin as a base material, durability against iodine contained in the electrolytic solution is ensured, and the battery seal The reliability of the part 4B is improved. This has been confirmed by testing. In particular, according to the present embodiment, the battery seal portion 4B includes a main seal portion 5B interposed between the photoelectrode 1 and the counter electrode 2B and formed of a thermosetting polyisobutylene resin as a base material. The inlet 9 is closed and the sub seal portion 6B is formed with an ultraviolet curable polyisobutylene resin as a base material. As shown in FIG. 3, the sub seal portion 6 </ b> B is disposed along the outer end side of the substrate 13. Since the main seal portion 5B is cured before injecting the electrolytic solution, there is little demand for instantaneous curing, so a thermosetting type is used. Since the secondary seal portion 6B is cured after injecting the electrolytic solution, there is a strong demand for instantaneous curing, so an ultraviolet curing type is used. For this reason, it is advantageous for suppressing gas such as the atmosphere from entering the electrolyte layer 3 accommodated between the photoelectrode 1 and the counter electrode 2B.

(Second test example)
The solar cell according to the second example was prepared as follows. Transparent glass was used as the substrate 13 on the photoelectrode 1 side. The size of the transparent glass was 30 mm × 25 mm × 1.1 mm. The transparent conductive layer 15 laminated on the substrate 13 on the photoelectrode 1 side was a SnO ₂ film doped with F and having a surface resistivity of 10Ω / □. Further, a groove 15m was formed by scribing, or scraping, the transparent conductive layer 15 at a pitch of 7 mm, thereby blocking the electrical conductivity of the adjacent conductive layer portion. Screen printing and baking at 450 ° C. are repeated on the transparent conductive layer 15 of the substrate on the side of the photoelectrode 1 to form a titanium oxide layer 16c to be an N-type semiconductor layer 16, a porous separator layer 7 and a counter electrode 2B. Carbon layers were laminated. After each layer is formed, the dye 18, that is, the ruthenium complex is adsorbed on the titanium oxide layer 16 c that becomes the N-type semiconductor layer 16 by immersing the substrate that becomes the photoelectrode 1 in an ethanol solution of ruthenium complex for a predetermined time (24 hours). I let you.

  Next, a polyisobutylene-based resin coating material is applied to the substrate 13 on which the titanium oxide layer 16c, the porous separator layer 7, and the carbon layer serving as the counter electrode 2B are mounted. By doing so, the main seal portion 5B was formed. And the electrolyte solution was inject | poured into the solar cell from the injection port 9 by vacuum deaeration operation and immersion operation to electrolyte solution. After injecting the electrolytic solution, an ultraviolet curable polyisobutylene resin is applied to the injection port 9, and ultraviolet irradiation is applied to the injection port 9 to cure the ultraviolet ray, thereby forming an auxiliary seal portion 6B that closes the injection port 9 and electrolysis. The liquid was sealed.

  About the solar cell produced as mentioned above, the high temperature leaving test which is left to stand at 85 degreeC was performed for 100 hours, and the low temperature standing test to be left to -40 degreeC was done for 100 hours. Even after the test, electrolyte leakage from the main seal portion 5B and the sub seal portion 6B did not occur.

(Third embodiment)
A third embodiment according to the present invention will be described. 4 to 6 show typical configurations of the dye-sensitized solar cell according to the third embodiment. The third embodiment has basically the same configuration as the second embodiment, and has the same effects. Parts common to the second embodiment are denoted by common reference numerals. Hereinafter, a description will be given centering on the difference from the second embodiment. As shown in FIG. 4, this solar cell includes a photoelectrode 1, a counter electrode 2B, a separator layer 7, an electrolyte layer 3, and a battery seal portion 4C. The electrolyte layer 3 is disposed between the photoelectrode 1 and the counter electrode 2B, and is formed of an electrolytic solution having fluidity. The battery seal portion 4C seals the electrolyte layer 3. The battery seal portion 4C is interposed between the photoelectrode 1 and the counter electrode 2B, and closes the main seal portion 5C formed using a thermosetting polyisobutylene resin as a base material, the injection port 9, and an ultraviolet curable type. It is formed with the sub seal part 6C formed using polyisobutylene resin as a base material. The main seal portion 5C surrounds and seals the periphery of the electrolyte layer 3.

  FIG. 6 shows the battery seal 4C before being bonded to the solar cell. The battery seal portion 4C before being bonded to the solar cell is a paste-like paste that becomes a main seal portion 5C having a base film 8 having flexibility and a polyisobutylene resin applied to one side of the base film 8 as a base material. It has a coating material 5H. The battery seal portion 4C before being bonded to the battery element is provided with an injection port 9 for injecting an electrolytic solution so as to penetrate the battery seal portion 4C in the thickness direction.

  Then, the step of bonding the coating material 5H of the battery seal portion 4C to the battery element is performed with the coating material 5H of the battery seal portion 4C facing the counter electrode 2B among the battery elements. In this case, the coating material 5H is pressurized and thermally cured to form the main seal portion 5C. As shown in FIG. 4, the thermoset main seal portion 5 </ b> C has an intermediate seal portion 5 w that covers and covers the adjacent counter electrodes 2 </ b> B, and a surface of each counter electrode 2 </ b> B opposite to the photoelectrode 1. It has the outer surface seal part 5x which coat | covers, and the outer edge seal part 5y which seals the outer edge of a solar cell.

  According to this embodiment, since the battery seal portion 4C is formed using a polyisobutylene resin as a base material, durability against iodine contained in the electrolytic solution is ensured, and the reliability of the battery seal portion 4C is improved. To do. This has been confirmed by testing. In particular, according to this embodiment, the battery seal portion 4C is interposed between the photoelectrode 1 and the counter electrode 2B, and is a main seal portion having a frame shape formed by using a thermosetting polyisobutylene resin as a base material. 5C and the sub seal part 6C formed by using the ultraviolet curable polyisobutylene resin as a base material while closing the injection port 9. Since the main seal portion 5C is cured before injecting the electrolytic solution, there is little demand for instantaneous curing, and therefore a thermosetting type is used. Since the sub seal portion 6C is cured after injecting the electrolytic solution, there is a strong demand for instantaneous curing in order to prevent leakage of the electrolytic solution, so an ultraviolet curing type is used. For this reason, it is advantageous for suppressing gas such as the atmosphere from entering the electrolyte layer 3 accommodated between the photoelectrode 1 and the counter electrode 2B.

  According to the present embodiment, the base material 8 may be coated with the coating material 5H based on the polyisobutylene resin in an amount necessary for adhesion. For this reason, the amount of the coating material 5H applied to the base film 8 can be minimized. For this reason, it is advantageous to suppress the excessive coating material 5H from penetrating into the solar cell from the surface of the counter electrode 2B layer or the like. Therefore, it is advantageous to suppress a decrease in the performance of the solar cell. In addition, as a material of the base film 8, 1 type, such as a high density polyethylene, polyester, nylon, silicone, or the resin film which laminated | stacked these can be used. In some cases, a metal foil may be used as the base film 8. Moreover, as the base film 8, you may use what formed the metal thin film in the resin film.

(Third test example)
A solar cell according to the third example was prepared as follows. This case is basically the same as the second test example. The size of the transparent glass forming the substrate 13 of the photoelectrode 1 was 30 mm × 25 mm × 1.1 mm. The transparent conductive layer 15 laminated on the substrate 13 on the photoelectrode 1 side was a SnO ₂ film doped with F and having a surface resistivity of 10Ω / □. Further, a groove 15m was formed by scribing the transparent conductive layer 15 at a pitch of 7 mm, that is, cutting it off, thereby blocking the electrical conductivity of the adjacent conductive layer portion. On the mounting surface 11 of the substrate 13 on the side of the photoelectrode 1, screen printing and baking at 450 ° C. are repeated to form a titanium oxide layer 16c that becomes an N-type semiconductor layer 16, a porous separator layer 7, and a counter electrode 2B. Each carbon layer was created. After forming each layer, the dye 18, that is, the ruthenium complex was adsorbed on the titanium oxide to be the N-type semiconductor layer 16 by immersing the substrate to be the photoelectrode 1 in an ethanol solution of the ruthenium complex for a predetermined time (24 hours). .

  As shown in FIG. 6, a battery seal portion 4 </ b> C having a base film 8 and a coating material 5 </ b> H (target thickness: 10 μm) laminated on one surface of the base film 8 and using a polyisobutylene resin as a base material was used. Then, the step of bonding the coating material 5H of the battery seal portion 4C to the battery element was performed with the coating material 5H of the battery seal portion 4C facing the counter electrode 2B among the battery elements. Then, press bonding was performed using a hot roll device held in a warm state (150 ° C.), and the coating material 5H was pressurized and thermally cured to form a main seal portion 5C.

  Then, electrolyte solution was inject | poured from the inlet 9 about 1 mm in diameter created beforehand so that it might penetrate to the battery seal part 4C in the thickness direction. After injecting the electrolytic solution, an ultraviolet curable polyisobutylene resin is applied to the injection port 9, and the polyisobutylene resin is UV-cured by spot irradiation with ultraviolet rays to form the sub-seal portion 6C. The electrolyte was sealed.

  About the solar cell produced as mentioned above, the high temperature leaving test which is left to stand at 85 degreeC was performed for 100 hours, and the low temperature standing test to be left to -40 degreeC was done for 100 hours. Even after the test, electrolyte leakage from the main seal portion 5C and the sub seal portion 6C did not occur.

  (Comparative Example) A solar cell according to a comparative example was produced. The comparative example has the same configuration as the first embodiment. However, an epoxy resin was used as the material for the battery seal. About the solar cell created by the said method, the high temperature leaving test in 85 degreeC and the low temperature leaving test in -40 degreeC were each performed. As a result, after 100 hours had passed in the high temperature storage test at 85 ° C., liquid leakage from the sub seal portion occurred. Further, after 100 hours had passed in the low temperature standing test at −40 ° C., both the main seal part and the sub seal part were peeled off, and electrolyte leakage occurred.

  (Other Examples) In addition, the present invention is not limited to the embodiments described above and shown in the drawings, and can be implemented with appropriate modifications within a range not departing from the gist.

It is a schematic sectional drawing which shows typically the dye-sensitized solar cell which concerns on 1st Example. It is a schematic sectional drawing which shows typically the dye-sensitized solar cell which concerns on 2nd Example. It is a schematic plan view which shows typically the dye-sensitized solar cell which concerns on 2nd Example. It is a schematic sectional drawing which shows typically the dye-sensitized solar cell which concerns on 3rd Example. It is a schematic plan view which shows typically the dye-sensitized solar cell which concerns on 3rd Example. It is a schematic sectional drawing which shows typically the battery seal part before bonding together to the dye-sensitized solar cell which concerns on 3rd Example.

Explanation of symbols

  In the figure, 1 is a light electrode, 10 is a light incident surface, 13 is a substrate, 15 is a transparent conductive layer, 16 is a semiconductor layer, 18 is a dye, 2 is a counter electrode, 3 is an electrolyte layer, 4 is a battery seal portion, and 5 is A main seal portion 6 indicates a sub seal portion.

Claims (4)

A photoelectrode having a light-transmitting substrate, a transparent conductive layer, an N-type semiconductor layer, and a dye;
A counter electrode facing the photoelectrode at a predetermined interval and having conductivity;
An electrolyte layer enclosed between the photoelectrode and the counter electrode;
In a dye-sensitized solar cell having a battery seal part that seals against the electrolyte layer,
A plurality of the counter electrode, the electrolyte layer, and the transparent conductive layer are arranged in series,
A dye-sensitized solar cell, comprising: a fine spherical filler that regulates a distance between the photoelectrode and the counter electrode, and an intermediate seal portion that covers and covers between the adjacent counter electrodes. The dye-sensitized solar cell according to claim 1, wherein the battery seal portion covers a surface of the counter electrode opposite to the photoelectrode. The dye-sensitized solar cell according to claim 1 or 2, wherein the intermediate seal portion is made of a thermosetting or ultraviolet curable polyisobutylene-based material. A battery element having a light-transmitting substrate, a transparent conductive layer, an N-type semiconductor layer, and a photoelectrode having a pigment, and a counter electrode facing the photoelectrode at a predetermined interval and having conductivity. As well as
Preparing a battery seal portion having a base film and a coating material based on a polyisobutylene resin applied to one side of the base film;
In a state where the coating material of the battery seal portion is opposed to the counter electrode of the battery element, the battery seal portion is bonded to the battery element and the coating material is cured.
A photoelectrode having a light-transmitting substrate, a transparent conductive layer, an N-type semiconductor layer, and a dye;
A counter electrode facing the photoelectrode at a predetermined interval and having conductivity;
An electrolyte layer enclosed between the photoelectrode and the counter electrode;
In a dye-sensitized solar cell having a battery seal part that seals against the electrolyte layer,
A plurality of the counter electrode, the electrolyte layer, and the transparent conductive layer are arranged in series,
A method for producing a dye-sensitized solar cell, characterized by producing a dye-sensitized solar cell comprising an intermediate seal portion that covers and covers between the adjacent counter electrodes.

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