JP6697348B2 - Photoelectric conversion element - Google Patents

Description

  The present invention relates to a photoelectric conversion element.

  As a photoelectric conversion element, a photoelectric conversion element using a dye has attracted attention because it is inexpensive and can obtain high photoelectric conversion efficiency, and various developments have been made on the photoelectric conversion element using the dye.

  As such a photoelectric conversion element, for example, one described in Patent Document 1 below is known. In Patent Document 1 below, a transparent substrate, at least one photoelectric conversion cell provided on one surface of the transparent substrate, and a water-blocking back sheet provided on one surface of the transparent substrate and covering at least one photoelectric conversion cell. , A ring-shaped connecting portion that is provided so as to surround at least one photoelectric conversion cell and connects the peripheral portion of the water-blocking sheet and the transparent substrate, and on one surface of the transparent substrate and outside the at least one photoelectric conversion cell. There is disclosed a photoelectric conversion element including an external output section that is provided across the annular coupling section and that outputs the voltage output from at least one photoelectric conversion cell to the outside.

Patent No. 5870196

  However, although the photoelectric conversion element described in Patent Document 1 has excellent durability even in a high humidity environment, the output voltage sometimes fluctuates depending on the illuminance of incident light. In this case, if the photoelectric conversion element is connected to a device driven by a constant voltage, the device may malfunction.

  Therefore, there has been a demand for a photoelectric conversion element having excellent durability even in a high humidity environment and capable of outputting a stable voltage regardless of the illuminance of incident light.

  The present invention has been made in view of the above circumstances, and has excellent durability even in a high humidity environment, and a photoelectric conversion element capable of outputting a stable voltage regardless of the illuminance of incident light. The purpose is to provide.

  In order to solve the above problems, the present invention provides a transparent substrate, at least one photoelectric conversion cell provided on one surface of the transparent substrate, and at least one photoelectric conversion cell provided on the one surface of the transparent substrate. And a ring-shaped sealing material that is provided on the one surface of the transparent substrate so as to surround the at least one photoelectric conversion cell and that connects the peripheral portion of the water-blocking sheet and the transparent substrate. A circuit board provided between the water-blocking sheet and the transparent substrate; a cell voltage output section provided on the transparent substrate for outputting a voltage from the at least one photoelectric conversion cell to the circuit board; On the one surface of the transparent substrate and outside the at least one photoelectric conversion cell, provided across the annular sealing material, an external output unit for outputting the voltage output from the circuit board to the outside, The circuit board includes an insulating substrate, an input terminal provided on the insulating substrate and connected to the cell voltage output section, and an inner terminal inside the sealing material of the external output section provided on the insulating substrate. It is a photoelectric conversion element which has an output terminal connected to an output part, and a circuit part which is provided in the above-mentioned insulating substrate and makes the voltage inputted from the above-mentioned input terminal into a fixed voltage, and outputs it to the above-mentioned output terminal.

  According to this photoelectric conversion element, a voltage is generated in at least one photoelectric conversion cell by light, and the voltage output from the at least one photoelectric conversion cell is passed from the input terminal of the circuit board to the circuit section via the cell voltage output section. After being input and having a constant voltage in the circuit section, it is output from the portion outside the annular seal member of the external output section via the output terminal and the external output section inside the external output section. That is, according to the present invention, a constant voltage is applied to the water-blocking sheet regardless of the illuminance of light incident on the photoelectric conversion element, without forming an opening for passing a wiring connected to the output terminal of the circuit board. Can be output. Further, according to the present invention, even under a high-humidity environment, invasion of moisture is sufficiently suppressed in the space between the water blocking sheet and the transparent substrate, and the circuit board is provided in this space. Therefore, deterioration of the circuit portion of the circuit board due to moisture is sufficiently suppressed. Therefore, the photoelectric conversion element of the present invention has excellent durability even in a high humidity environment and can output a stable voltage regardless of the illuminance of incident light.

  In the photoelectric conversion element, the photoelectric conversion cell includes a transparent conductive layer provided on the one surface of the transparent substrate, and a counter substrate facing the transparent conductive layer, the circuit board, the counter substrate and When the circuit board is viewed in the thickness direction of the transparent substrate, it is preferably arranged so as to at least partially overlap the counter substrate.

  In this case, since the circuit board is arranged so as to at least partially overlap the counter substrate and the circuit substrate when the circuit substrate is viewed in the thickness direction of the transparent substrate, the photoelectric conversion cell is provided on the transparent substrate. It is possible to reduce the area where the circuit board is installed, that is, the area that does not contribute to power generation, in the area that is not provided. Therefore, the aperture ratio of the photoelectric conversion element can be increased.

  In the photoelectric conversion element, the counter substrate includes a metal substrate, and the circuit board projects from the counter substrate when the counter substrate and the circuit board are viewed in a thickness direction of the transparent substrate. The input terminal and the output terminal are provided on the projecting portion, the input terminal and the cell voltage output portion are connected by a first conductive member, and the output terminal and the inner external portion of the external output portion. It is preferable that the output portion is connected by the second conductive member.

  In this case, since the input terminal and the output terminal of the circuit portion are provided on the protruding portion of the counter substrate that is separated from the metal substrate, the first conductive member or the second conductive member is less likely to contact the metal substrate of the counter substrate, A short circuit between the input terminal and the output terminal due to the contact between the first conductive member and the second conductive member with the metal substrate of the counter substrate is sufficiently suppressed.

  According to the present invention, there is provided a photoelectric conversion element having excellent durability even in a high humidity environment and capable of outputting a stable voltage regardless of the illuminance of incident light.

It is sectional drawing which shows the suitable embodiment of the photoelectric conversion element of this invention. It is a top view which shows a part of suitable embodiment of the photoelectric conversion element of this invention. It is a perspective view which shows the positional relationship of the circuit board of FIG. 1, and an external output part. It is a top view which shows the pattern of the transparent conductive layer in the photoelectric conversion element of FIG. It is a top view which shows the integrated sealing part of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5. 1 is a sectional view showing a preferred embodiment of the photoelectric conversion element of the present invention, FIG. 2 is a plan view showing a part of a preferred embodiment of the photoelectric conversion element of the present invention, and FIG. FIG. 4 is a perspective view showing the positional relationship between the circuit board and the external output section, FIG. 4 is a plan view showing a pattern of the transparent conductive layer in the photoelectric conversion element of FIG. 1, and FIG. 5 is a view showing the integrated sealing section of FIG. It is a top view.

  As shown in FIGS. 1 and 2, the photoelectric conversion element 100 includes a transparent substrate 11, a plurality (four in FIG. 1) of photoelectric conversion cells 50 provided on one surface 11 a of the transparent substrate 11, and a transparent substrate 11. A water shield sheet 80 provided on the one surface 11a and covering the plurality of photoelectric conversion cells 50, and a peripheral portion of the water shield sheet 80 provided on the one surface 11a of the transparent substrate 11 so as to surround the plurality of photoelectric conversion cells 50. An annular sealing material 14 that connects the transparent substrate 11 to the transparent substrate 11, a circuit board 120 provided in the space between the water-blocking sheet 80 and the transparent substrate 11, and a plurality of photoelectric conversion cells provided on the transparent substrate 11. A transparent conductive layer 12H as a cell voltage output unit for outputting a voltage from 50 to the circuit board 120, and a ring-shaped sealing material 14 provided on one surface 11a of the transparent substrate 11 and outside the plurality of photoelectric conversion cells 50. And a transparent conductive layer 12G as an external output unit that outputs the voltage output from the circuit board 120 to the outside.

  As shown in FIG. 2, the plurality of photoelectric conversion cells 50 are connected in series by a conductive material 60P. Hereinafter, for convenience of description, the four photoelectric conversion cells 50 in the photoelectric conversion element 100 may be referred to as photoelectric conversion cells 50A to 50D.

  As shown in FIG. 1, each of the plurality of photoelectric conversion cells 50 includes a transparent conductive layer 12 provided on one surface 11a of the transparent substrate 11, a counter substrate 20 facing the transparent conductive layer 12, a transparent substrate 11 and a counter substrate. An annular sealing portion 30 </ b> A for joining the substrates 20, an electrolyte 40 arranged in the cell space formed by the transparent conductive layer 12, the counter substrate 20 and the annular sealing portion 30, and provided on the transparent conductive layer 12. Oxide semiconductor layer 13 that is formed. The oxide semiconductor layer 13 is arranged inside the ring-shaped sealing portion 30, and the oxide semiconductor layer 13 carries a dye.

  The counter substrate 20 includes a metal substrate 21 and a catalyst layer 22 provided on the transparent conductive layer 12 side of the metal substrate 21 to promote a catalytic reaction. In the two adjacent photoelectric conversion cells 50, the counter substrates 20 are separated from each other.

  As shown in FIG. 4, the transparent conductive layer 12 is composed of transparent conductive layers 12A to 12J.

  Of the transparent conductive layers 12A to 12J, the transparent conductive layers 12A to 12D form the transparent conductive layers 12 of the plurality of photoelectric conversion cells 50A to 50D, respectively.

  Each of the transparent conductive layers 12A to 12D has a quadrangular main body 12a having a side edge 12b and a protrusion 12c protruding laterally from the side edge 12b of the main body 12a.

  As shown in FIG. 2, among the transparent conductive layers 12A to 12D, the protruding portion 12c of the transparent conductive layer 12C has a projecting portion 12d that projects laterally with respect to the arrangement direction X of the photoelectric conversion cells 50A to 50D and a projecting portion. It has an opposing portion 12e extending from 12d and opposing the main body portion 12a of the adjacent photoelectric conversion cell 50D via the groove 90.

  Also in the photoelectric conversion cell 50B, the protruding portion 12c of the transparent conductive layer 12B has an overhanging portion 12d and a facing portion 12e. Also in the photoelectric conversion cell 50A, the protruding portion 12c of the transparent conductive layer 12A has an overhanging portion 12d and a facing portion 12e.

  The photoelectric conversion cell 50D is already connected to the photoelectric conversion cell 50C, and there is no other photoelectric conversion cell 50 to be connected. Therefore, in the photoelectric conversion cell 50D, the protruding portion 12c of the transparent conductive layer 12D does not have the facing portion 12e. That is, the protruding portion 12c of the transparent conductive layer 12D is composed of only the protruding portion 12d.

  The transparent conductive layer 12J and the transparent conductive layer 12H are connected to and integrated with the transparent conductive layer 12D. The transparent conductive layer 12H is a cell voltage output portion, the transparent conductive layer 12J connects the transparent conductive layer 12H and the transparent conductive layer 12D, and extends along the side edge portion 12b of the transparent conductive layers 12A to 12C. There is. Internal terminals 18c are provided on the transparent conductive layer 12H.

  The transparent conductive layer 12E is a grounding transparent conductive layer, and the internal terminal 18d is provided on the transparent conductive layer 12E.

  The transparent conductive layer 12G is an external output part, and the internal terminal 18a and the external terminal 18b are provided on the transparent conductive layer 12G. The internal terminals 18a are provided on the inside external output portion inside the sealing material 14, and the external terminals 18b are provided on the outside external output portion outside the sealing material 14.

  The transparent conductive layer 12I is a grounding transparent conductive layer, and the internal terminal 18e and the external terminal 18f are provided on the transparent conductive layer 12I. Here, the internal terminal 18e is provided inside the sealing material 14, and the external terminal 18f is provided outside the sealing material 14.

  The transparent conductive layer 12G as an external output section, the transparent conductive layer 12H as a cell voltage output section, the grounding transparent conductive layer 12E and the grounding transparent conductive layer 12I are different from the transparent conductive layer 12A of the photoelectric conversion cell 50A. It is arranged on the opposite side of the transparent conductive layer 12B and arranged in a line along the peripheral edge of the transparent substrate 11. The transparent conductive layer 12G as an external output section, the transparent conductive layer 12H as a cell voltage output section, the grounding transparent conductive layer 12E and the grounding transparent conductive layer 12I are all provided across the sealing material 14.

  The transparent conductive layers 12A to 12J described above are separated from each other by the groove 90 except the transparent conductive layers 12D, 12H, and 12J. Here, the groove 90 is formed along the first groove 90A formed along the edge of the main body portion 12a of the transparent conductive layer 12 and along the edge of the transparent conductive layer 12 excluding the main body portion 12a. The second groove 90B intersects the peripheral edge portion 80a of the water-blocking sheet 80.

  A connection terminal 16 is provided on each of the protrusions 12c of the transparent conductive layers 12A to 12C and the transparent conductive layer 12E.

  Then, the connection terminal 16 provided on the protruding portion 12c of the transparent conductive layer 12C in the photoelectric conversion cell 50C and the metal substrate 21 of the counter substrate 20 in the adjacent photoelectric conversion cell 50D are connected via the conductive material 60P. Similarly, the connection terminal 16 in the photoelectric conversion cell 50B and the metal substrate 21 of the counter substrate 20 in the adjacent photoelectric conversion cell 50C are connected via the conductive material 60P, and the photoelectric conversion cell adjacent to the connection terminal 16 in the photoelectric conversion cell 50A is connected. The metal substrate 21 of the counter substrate 20 in the cell 50B is connected via the conductive material 60P, and the connection terminal 16 on the transparent conductive layer 12E and the metal substrate 21 of the counter substrate 20 in the adjacent photoelectric conversion cell 50A are the conductive material 60P. Connected through.

  As shown in FIG. 3, the circuit board 120 includes an insulating substrate 121, an input terminal 122 provided on the insulating substrate 121 and connected to the transparent conductive layer 12H as a cell voltage output unit of the plurality of photoelectric conversion cells 50, An output terminal 123 provided on the insulating substrate 121 and connected to an inner external output portion inside the sealing material 14 of the transparent conductive layer 12G as an external output portion, and a transparent conductive layer 12E for grounding provided on the insulating substrate 121. A second ground terminal 126 provided on the insulating substrate 121 and connected to the grounding transparent conductive layer 12I, and a voltage provided from the input terminal 122 provided on the insulating substrate 121. To a constant voltage and outputs the voltage to the output terminal 123. Here, the circuit section 124 is for making the input voltage constant by increasing or decreasing it, and is electrically connected to the input terminal 122, the output terminal 123, the first ground terminal 125, and the second ground terminal 126. Has been done. Note that the first ground terminal 125 and the second ground terminal 126 are electrically connected to the circuit section 124 so as to apply a ground potential.

  The circuit board 120 is arranged so as to partially overlap with the counter substrate 20 when the counter substrate 20 and the circuit board 120 are viewed in the thickness direction of the transparent substrate 11. That is, the circuit board 120 includes the counter substrate 20 and the protrusion 127 that protrudes from the counter substrate 20 when the circuit substrate 120 is viewed in the thickness direction of the transparent substrate 11, and the protrusion 127 covers the input terminal 122 and the output terminal. 123, a first ground terminal 125, and a second ground terminal 126 are provided. More specifically, the input terminal 122 is provided on the transparent conductive layer 12H side as the cell voltage output part of the protrusion 127, and the output terminal 123 is on the transparent conductive layer 12G side as the external output part of the protrusion 127. The first ground terminal 125 is provided on the grounding transparent conductive layer 12E side of the protrusion 127, and the second ground terminal 126 is provided on the grounding transparent conductive layer 12I side of the protrusion 127. ..

  The output terminal 123 of the circuit board 120 and the transparent conductive layer 12G as an external output section are connected by the first conductive member 130, and the input terminal 122 of the circuit board 120 and the transparent conductive layer 12H as a cell voltage output section. Are connected by the second conductive member 131, the first ground terminal 125 of the circuit board 120 and the transparent conductive layer 12E are connected by the third conductive member 132, and the second ground terminal 126 of the circuit board 120 and the transparent conductive layer 12I. Are connected by a fourth conductive member 133.

  A current collecting wiring 17 having a resistance lower than that of the transparent conductive layer 12D extends on the main body portion 12a of the transparent conductive layer 12D, the connecting portion 12J, and the transparent conductive layer 12H as a cell voltage output portion. The current collecting wiring 17 is arranged so as not to intersect the sealing material 14. In other words, the current collection wiring 17 is arranged inside the sealing material 14.

  As shown in FIG. 1, the sealing section 30 is provided between the transparent substrate 11 and the counter substrate 20. Then, as shown in FIG. 5, the adjacent first sealing portions 30 are integrated to form a first integrated sealing portion 31. In other words, the first integrated sealing portion 31 includes an annular portion (hereinafter, referred to as “annular portion”) 31a that is not provided between two adjacent counter substrates 20 and two adjacent counter substrates. It is provided between 20 and is configured by a part (hereinafter, referred to as a “partition part”) 31b that partitions the inner opening 31c of the annular part 31a.

  Further, as shown in FIG. 1, between the sealing portion 30 and the groove 90, the insulating material 33 is inserted into the groove 90 between the adjacent transparent conductive layers 12A to 12I and straddles the adjacent transparent conductive layer 12. Is provided. More specifically, the insulating material 33 enters the first groove 90A formed along the edge of the main body portion 12a of the transparent conductive layer 12 in the groove 90, and forms the first groove 90A. It also covers the edge of section 12.

  The water-blocking sheet 80 includes a main body formed of a laminated body including a weather resistant layer and a metal layer, and an adhesive layer 91 provided on the transparent substrate 11 side of the main body and bonded to the sealing material 14. Including. The adhesive layer 91 is to be adhered to the surface of the main body portion on the transparent substrate 11 side, and may be formed on the peripheral portion of the main body portion, or on the entire surface of the main body portion on the photoelectric conversion cell 50 side. It may be provided. The peripheral portion 80a of the water-blocking sheet 80 is connected to the transparent conductive layers 12D, 12E, 12F, 12G, 12H, 12I of the transparent conductive layer 12 via the sealing material 14 by the adhesive portion 91.

  According to the photoelectric conversion element 100, a voltage is generated in the plurality of photoelectric conversion cells 50A to 50D by light, and the voltage output from the plurality of photoelectric conversion cells 50A to 50D is the transparent conductive layer 12H as the cell voltage output unit. After being input from the input terminal 122 of the circuit board 120 to the circuit section 124 and having a constant voltage in the circuit section 124, the output terminal 123 and the inner external output section of the transparent conductive layer 12G as an external output section are passed through. , Is output from the outer external output portion on the outer side of the annular sealing material 14 of the transparent conductive layer 12G as the external output portion. That is, according to the photoelectric conversion element 100, the illuminance of light incident on the photoelectric conversion element 100 does not occur in the water shield sheet 80 without forming an opening for passing a wiring connected to the output terminal 123 of the circuit board 120. Instead, a constant voltage can be output. Further, according to the photoelectric conversion element 100, the invasion of moisture is sufficiently suppressed in the space between the water blocking sheet 80 and the transparent substrate 11 even in a high humidity environment, and the circuit board 120 is provided in this space. There is. Therefore, the circuit portion 124 of the circuit board 120 is sufficiently suppressed from being deteriorated by moisture. Therefore, the photoelectric conversion element 100 has excellent durability even in a high humidity environment, and can output a stable voltage regardless of the illuminance of incident light.

  Further, in the photoelectric conversion element 100, the circuit board 120 is arranged so as to partially overlap the counter substrate 20 and the circuit board 120 when viewed in the thickness direction of the transparent substrate 11. Therefore, in the area on the transparent substrate 11 where the photoelectric conversion cells 50 are not provided, the area for installing the circuit board 120, that is, the area that does not contribute to power generation can be reduced. Therefore, the aperture ratio of the photoelectric conversion element 100 can be increased.

  Further, in the photoelectric conversion element 100, the circuit board 120 includes the counter substrate 20 and the protrusion 127 that protrudes from the counter substrate 20 when the circuit substrate 120 is viewed in the thickness direction of the transparent substrate 11, and the protrusion 127. Is provided with an input terminal 122 and an output terminal 123, the input terminal 122 and the transparent conductive layer 12H as a cell voltage output section are connected by a first conductive member 131, and the output terminal 123 and a transparent conductive layer 12G as an external output section are connected. And the inner external output portion of are connected by the second conductive member 130.

  Therefore, since the input terminal 122 and the output terminal 123 of the circuit portion 124 are provided on the protruding portion 127 of the counter substrate 20 which is separated from the metal substrate 21, the first conductive member 131 or the second conductive member 130 is the counter substrate 20. Of the first conductive member 131 and the second conductive member 130 are both in contact with the metal substrate 21 of the counter substrate 20, and a short circuit between the input terminal 122 and the output terminal 123 is sufficiently suppressed. To be done.

  Next, the transparent substrate 11, the transparent conductive layer 12, the connection terminal 16, the oxide semiconductor layer 13, the sealing material 14, the dye, the counter substrate 20, the sealing portion 30, the insulating material 33, the electrolyte 40, the conductive material 60P, the water shield. The sheet 80, the circuit board 120, and the first to fourth conductive members 130 to 133 will be described in detail.

(Transparent substrate)
The material forming the transparent substrate 11 may be, for example, a transparent material, and examples of such a transparent material include borosilicate glass, soda lime glass, white plate glass, glass such as quartz glass, and polyethylene terephthalate (PET). , Polyethylene naphthalate (PEN), polycarbonate (PC), and polyether sulfone (PES). The thickness of the transparent substrate 11 is appropriately determined according to the size of the photoelectric conversion element 100 and is not particularly limited, but may be, for example, in the range of 50 to 40,000 μm.

(Transparent conductive layer)
Examples of materials forming the transparent conductive layer 12 include conductive metal oxides such as tin-added indium oxide (ITO), tin oxide (SnO ₂ ), and fluorine-added tin oxide (FTO). The transparent conductive layer 12 may be a single layer or a laminate of a plurality of layers made of different conductive metal oxides. When the transparent conductive layer 12 is composed of a single layer, the transparent conductive layer 12 is preferably composed of FTO because it has high heat resistance and chemical resistance. The thickness of the transparent conductive layer 12 may be in the range of 0.01 to 2 μm, for example.

(Connecting terminal)
The connection terminal 16 includes a metal material. Examples of the metal material include silver, copper and indium. You may use these individually or in combination of 2 or more types.

  Further, the connection terminal 16 may be made of the same material as the conductive material 60P or may be made of a different material, but is preferably made of the same material.

  In this case, since the connection terminal 16 and the conductive material 60P are made of the same material, the adhesion between the connection terminal 16 and the conductive material 60P can be more sufficiently improved. Therefore, the connection reliability of the photoelectric conversion element 100 can be further improved.

(Oxide semiconductor layer)
The oxide semiconductor layer 13 is composed of oxide semiconductor particles. The oxide semiconductor particles include, for example, titanium oxide (TiO ₂ ), zinc oxide (ZnO), tungsten oxide (WO ₃ ), niobium oxide (Nb ₂ O ₅ ), strontium titanate (SrTiO ₃ ), tin oxide (SnO ₂ ). , indium oxide _{(In 3 O 3),} zirconium oxide _(ZrO 2), thallium oxide _{(Ta 2 O} 5), lanthanum oxide _{(La 2 O} 3), yttrium oxide _{(Y 2 O} 3), holmium oxide _(Ho 2 O ₃ ), bismuth oxide (Bi ₂ O ₃ ), cerium oxide (CeO ₂ ), aluminum oxide (Al ₂ O ₃ ), or two or more of these. The oxide semiconductor layer 50 may have a thickness of 0.1 to 100 μm, for example.

(Seal material)
The material forming the sealing material 14 is not particularly limited as long as it can bond the adhesive portion 91 and the transparent conductive layer 12, and examples of the material forming the sealing material 14 include a glass frit and a sealing portion. A resin material similar to the resin material used for 30 can be used. Above all, the sealing material 14 is preferably a glass frit. Since the glass frit has a higher sealing ability than the resin material, it is possible to effectively suppress the intrusion of water and the like from the outside of the water shield sheet 80 and the adhesive portion 91.

(Pigment)
As the dye, for example, a ruthenium complex having a ligand containing a bipyridine structure, a terpyridine structure, or the like, a photosensitizing dye such as an organic dye such as porphyrin, eosin, rhodamine, or merocyanine, or an organic material such as a lead halide perovskite crystal. -Inorganic composite dyes and the like are included. As the lead halide perovskite, for example, CH ₃ NH ₃ PbX ₃ (X = Cl, Br, I) is used. Among the above dyes, a ruthenium complex having a ligand containing a bipyridine structure or a terpyridine structure is preferable. In this case, the photoelectric conversion characteristics of the photoelectric conversion element 100 can be further improved. When a photosensitizing dye is used as the dye, the photoelectric conversion element 100 becomes a dye-sensitized photoelectric conversion element.

(Counter substrate)
As described above, the counter substrate 20 includes the metal substrate 21, and the conductive catalyst layer 22 provided on the transparent substrate 11 side of the metal substrate 21 and promoting the reduction reaction on the surface of the counter substrate 20.

  The metal substrate 21 is made of a corrosion-resistant metal material such as titanium, nickel, platinum, molybdenum, tungsten, aluminum, and stainless. The thickness of the metal substrate 21 is appropriately determined according to the size of the photoelectric conversion element 100 and is not particularly limited, but may be, for example, 0.005 to 0.1 mm.

  The catalyst layer 22 is made of platinum, a carbon-based material, a conductive polymer, or the like.

(Sealing part)
Examples of the sealing portion 30 include a modified polyolefin resin, a thermoplastic resin such as a vinyl alcohol copolymer, and a resin such as an ultraviolet curable resin. Examples of the modified polyolefin resin include ionomers, ethylene-vinyl acetic anhydride copolymers, ethylene-methacrylic acid copolymers, and ethylene-vinyl alcohol copolymers. These resins can be used alone or in combination of two or more kinds.

  The thickness of the sealing portion 30 is usually 40 to 90 μm, preferably 60 to 80 μm.

(Insulating material)
The insulating material 33 may be made of an insulating material, and examples of such an insulating material include glass frit. The thickness of the insulating material 33 is usually 10 to 30 μm, preferably 15 to 25 μm.

(Electrolytes)
The electrolyte 40 contains a redox couple and an organic solvent. As the organic solvent, acetonitrile, methoxyacetonitrile, methoxypropionitrile, propionitrile, ethylene carbonate, propylene carbonate, diethyl carbonate, γ-butyrolactone, valeronitrile, pivalonitrile, etc. can be used. Examples of the redox couple include redox couples containing a halogen atom such as iodide ion / polyiodide ion (for example, I ⁻ / I ₃ ⁻ ), bromide ion / polybromide ion, zinc complex, iron complex, and cobalt complex. Redox pairs such as. The iodide ion / polyiodide ion can be formed by iodine (I ₂ ) and a salt (ionic liquid or solid salt) containing iodide (I ⁻ ) as an anion. When using an ionic liquid having iodide as the anion, only iodine needs to be added. When an ionic liquid other than iodide is used as the anion, as an anion such as LiI or tetrabutylammonium iodide. A salt containing iodide (I ⁻ ) may be added. The electrolyte 40 may use an ionic liquid instead of the organic solvent. As the ionic liquid, for example, a known iodine salt such as a pyridinium salt, an imidazolium salt, a triazolium salt, or the like is used. Examples of such an iodine salt include 1-hexyl-3-methylimidazolium iodide, 1-ethyl-3-propylimidazolium iodide, 1-ethyl-3-methylimidazolium iodide, 1,2- Dimethyl-3-propylimidazolium iodide, 1-butyl-3-methylimidazolium iodide, or 1-methyl-3-propylimidazolium iodide is preferably used.

  The electrolyte 40 may use a mixture of the ionic liquid and the organic solvent instead of the organic solvent.

  Additives can be added to the electrolyte 40. Examples of the additive include benzimidazoles such as 1-methylbenzimidazole (NMB) and 1-butylbenzimidazole (NBB), LiI, tetrabutylammonium iodide, 4-t-butylpyridine, and guanidinium thiocyanate. .. Among them, benzimidazole is preferable as the additive.

Further, as the electrolyte 40, a nanocomposite gel electrolyte, which is a pseudo-solid electrolyte formed by kneading nanoparticles such as SiO ₂ , TiO ₂ , and carbon nanotubes with the above electrolyte to form a gel, may be used. An electrolyte gelated with an organic gelling agent such as a polyethylene oxide derivative or an amino acid derivative may be used.

(Conductive material)
A metal film, for example, is used as the conductive material 60P. As the metal material forming the metal film, for example, silver or copper can be used.

(Water impermeable sheet)
As described above, the water-blocking sheet 80 is provided on the main body including the weather resistant layer and the metal layer and on the surface of the main body on the photoelectric conversion cell 50 side, and the sealing material 14 and the transparent conductive layers 12E, 12F, 12G or And an adhesive layer 91 adhered to the transparent substrate 11 via 12H.

  The weather resistant layer may be made of, for example, polyethylene terephthalate or polybutylene terephthalate.

  The thickness of the weather resistant layer may be, for example, 50 to 300 μm.

  The metal layer may be made of a metal material containing aluminum, for example. The metal material is usually composed of aluminum alone, but may be an alloy of aluminum and another metal. Examples of other metals include copper, manganese, zinc, magnesium, lead, and bismuth. Specifically, 1000 series aluminum in which a trace amount of other metal is added to 98% or more of pure aluminum is desirable. This is because this 1000-series aluminum is cheaper and has better workability than other aluminum alloys.

  The thickness of the metal layer is not particularly limited, but may be 12 to 30 μm, for example.

  The main body may further include a resin layer. Examples of the material forming the resin layer include butyl rubber, nitrile rubber, and thermoplastic resin. These may be used alone or in combination of two or more. The resin layer may be formed on the entire surface of the metal layer on the side opposite to the weather resistant layer, or may be formed only on the peripheral portion.

  Examples of the material forming the adhesive layer 91 include butyl rubber, nitrile rubber, and thermoplastic resin. These may be used alone or in combination of two or more.

  The thickness of the adhesive layer 91 is not particularly limited, but may be 300 to 6000 μm, for example.

(Circuit board)
As described above, the circuit board 120 includes the insulating board 121, the input terminal 122, the output terminal 123, the first ground terminal 125, the second ground terminal 126, and the circuit section 124.

  The insulating substrate 121 may be made of an insulating material, and for example, glass epoxy can be used as the insulating material.

  The thickness of the insulating substrate 121 is not particularly limited, but may be 0.4 to 3.2 mm, for example.

  Materials forming the input terminal 122, the output terminal 123, the first ground terminal 125, and the second ground terminal 126 are not particularly limited as long as they have conductivity. The output terminal 123, the first ground terminal 125, and the second ground terminal 126 may be made of the same material as the conductive material 60P or different materials, but are usually the same material as the conductive material 60P. Composed of. The input terminal 122 is composed of a layer made of copper, or is obtained by plating a layer made of copper with gold or solder.

  The circuit unit 124 may be any unit that raises or lowers the input voltage to a constant voltage. As such a circuit unit 124, for example, a power supply integrated circuit (IC) or the like can be used.

(First to fourth conductive members)
The first to fourth conductive members 130 to 133 are made of, for example, a conductive adhesive. Examples of the conductive adhesive include an adhesive obtained by adding silver to an epoxy resin.

  Next, a method for manufacturing the photoelectric conversion element 100 will be described with reference to FIG.

  First, a laminate is prepared in which a transparent conductive film is formed on one surface 11a of one transparent substrate 11.

  As a method for forming the transparent conductive film, a sputtering method, a vapor deposition method, a spray pyrolysis method, a chemical vapor deposition (CVD) method, or the like is used.

  Next, as shown in FIG. 4, a groove 90 is formed in the transparent conductive film and transparent conductive layers 12A to 12J are formed.

The groove 90 can be formed by a laser scribing method using, for example, a YAG laser or a CO ₂ laser as a light source.

  Thus, the transparent conductive layer 12 is formed on the one surface 11a of the transparent substrate 11 to obtain a conductive substrate.

  Next, the precursor of the connection terminal 16 is formed on the protrusion 12c of the transparent conductive layers 12A to 12C. Further, a precursor of the connection terminal 16 is also formed on the transparent conductive layer 12E. The precursor of the connection terminal 16 can be formed, for example, by applying a silver paste and drying it.

  Further, a precursor of the current collecting wiring 17 is formed on the connecting portion 12J. The precursor of the current collecting wiring 17 can be formed, for example, by applying a silver paste and drying it.

  Further, on the transparent conductive layer 12G as an external output portion, the transparent conductive layer 12H as a cell voltage output portion, the grounding transparent conductive layer 12E and the grounding transparent conductive layer 12I, the internal terminals 18a, 18c, 18d and 18e are respectively provided. A precursor and a precursor of the external terminals 18b and 18f are formed. The precursor of the internal terminal and the precursor of the external terminal can be formed, for example, by applying a silver paste and drying.

  Further, a precursor of the insulating material 33 is formed so as to enter the first groove 90A formed along the edge of the body 12a and cover the edge of the body 12a. The precursor of the insulating material 33 can be formed by, for example, applying a paste containing an insulating material and drying it.

  In order to fix the water blocking sheet 80, the transparent conductive layer 12D, the transparent conductive layer 12E, the transparent conductive layer 12F, the transparent conductive layer 12G, and the transparent conductive layer are formed in the same manner as the insulating material 33 so as to surround the insulating material 33. A precursor of the annular sealing material 14 is formed so as to pass over the 12H and the transparent conductive layer 12I.

  Further, a precursor of the oxide semiconductor layer 13 is formed on the main body 12a of each of the transparent conductive layers 12A to 12D. The precursor of the oxide semiconductor layer 13 can be formed by printing an oxide semiconductor layer forming paste containing oxide semiconductor particles and then drying the paste.

  The oxide semiconductor layer forming paste contains oxide semiconductor particles, a resin such as polyethylene glycol, and a solvent such as terpineol.

  As a method for printing the oxide semiconductor layer forming paste, for example, a screen printing method, a doctor blade method, a bar coating method or the like can be used.

  Finally, the precursor of the connection terminal 16, the precursor of the insulating material 33, the precursor of the sealing material 14, the precursor of the internal terminals 18a, 18c, 18d, 18e, the precursor of the external terminals 18b, 18f, and the oxide semiconductor layer. The precursor of 13 is collectively fired, and the connection terminal 16, the current collecting wiring 17, the insulating material 33, the sealing material 14, the internal terminals 18a, 18c, 18d, 18e, the external terminals 18b, 18f and The oxide semiconductor layer 13 is formed.

  At this time, the firing temperature varies depending on the type of oxide semiconductor particles, glass frit, etc., but is usually 350 to 600 ° C., and the firing time also varies depending on the type of oxide semiconductor particles, glass frit, etc., but usually 1 ~ 5 hours.

  Thus, on the conductive substrate, the connection terminal 16, the current collection wiring 17, the insulating material 33, the sealing material 14 for fixing the water-blocking sheet 80, the internal terminals 18a, 18c, 18d, 18e, the external terminals 18b, 18f and A structure in which the oxide semiconductor layer 13 is formed is obtained.

  Next, the dye is supported on the oxide semiconductor layer 13 of the structure obtained as described above. For this purpose, the structure is dipped in a solution containing a dye, the dye is adsorbed to the oxide semiconductor layer 13, and then the excess dye is washed away with the solvent component of the solution and dried. The dye may be adsorbed on the oxide semiconductor layer 13. However, even if the dye is adsorbed to the oxide semiconductor layer 13 by applying a solution containing the dye to the oxide semiconductor layer 13 and then drying the solution, the dye can be supported on the oxide semiconductor layer 13. ..

  Next, the electrolyte 40 is arranged on the oxide semiconductor layer 13.

  Next, a sealed portion forming body for forming the sealed portion 30 is prepared. The encapsulation part formation body prepares one encapsulation resin film made of the material forming the encapsulation part 30, and forms square openings corresponding to the number of photoelectric conversion cells 50 in the encapsulation resin film. It can be obtained by forming. The sealed portion forming body has a structure formed by integrating a plurality of sealed portion forming bodies.

  Examples of the resin film for sealing include ionomer, ethylene-vinyl acetic anhydride copolymer, ethylene-methacrylic acid copolymer, modified polyolefin resin containing ethylene-vinyl alcohol copolymer, UV-curable resin, and vinyl. Examples include resins such as alcohol polymers.

  Then, the sealing portion forming body is adhered onto the structure. At this time, the sealing portion forming body is bonded to the structure so as to overlap the insulating material 33. The sealing portion forming body can be bonded to the structure by heating and melting the sealing portion forming body. Further, the sealing portion forming body is bonded to the structure so that the main body portion 12a of the transparent conductive layer 12 is arranged inside the sealing portion forming body.

  On the other hand, the same number of counter substrates 20 as the photoelectric conversion cells 50 are prepared.

  The counter substrate 20 can be obtained by forming a conductive catalyst layer 22 that promotes a reduction reaction on the surface of the counter substrate 20 on the metal substrate 21.

  Next, another sealing portion forming body described above is prepared. Then, each of the plurality of counter substrates 20 is bonded so as to close each opening of the sealing portion forming body.

  Next, the sealing portion forming body adhered to the counter substrate 20 and the sealing portion forming body adhered to the structure are superposed, and the sealing portion forming body is heated and melted while being pressurized. In this way, the sealing portion 30 is formed between the structure and the counter substrate 20. The formation of the sealing portion 30 may be performed under atmospheric pressure or under reduced pressure, but it is preferably performed under reduced pressure.

  Next, a paste containing a metal material forming the conductive material 60P is prepared, and this paste is applied so as to connect the counter substrate 20 and the connection terminal 16 of the adjacent photoelectric conversion cell 50, and cured. As the above-mentioned paste, it is preferable to use a low-temperature curable paste that can be cured at a temperature of 90 ° C. or lower from the viewpoint of avoiding adverse effects on the dye.

  Next, the circuit board 120 is prepared and fixed on the counter substrate 20 of the photoelectric conversion cell 50A. At this time, the circuit board 120 is arranged so that the circuit board 120 and the counter substrate 20 of the photoelectric conversion cell 50A partially overlap each other when viewed in the thickness direction of the transparent substrate 11. That is, when the circuit board 120 and the counter substrate 20 of the photoelectric conversion cell 50A are viewed in the thickness direction of the transparent substrate 11, the circuit board 120 is arranged so that a part of the circuit board 120 projects outward from the counter substrate 20. .. At this time, the input terminal 122, the output terminal 123, the first ground terminal 125 and the second ground terminal 126 are provided on the protrusion 127 of the circuit board 120 on the transparent substrate 11 side. Specifically, the input terminal 122 faces the internal terminal 18c provided on the transparent conductive layer 12H as a cell voltage output part, and the output terminal 123 is provided on the transparent conductive layer 12G as an external output part. The first ground terminal 125 faces the internal terminal 18d installed on the grounding transparent conductive layer 12E, and the second ground terminal 126 installs on the grounding transparent conductive layer 12I. The circuit board 120 is arranged to face the internal terminal 18e. The circuit board 120 can be fixed to the counter substrate 20 by using, for example, an insulating adhesive material.

  Then, the input terminal 122 and the internal terminal 18c are connected by the first conductive member 131, the output terminal 123 and the internal terminal 18a are connected by the second conductive member 130, and the first ground terminal 125 and the internal terminal 18d are connected by the first conductive member 131. The third conductive member 132 is connected, and the second ground terminal 126 and the internal terminal 18e are connected by the fourth conductive member 133.

  Finally, the water blocking sheet 80 is prepared. Then, the adhesive portion 91 of the peripheral edge portion 80 a of the water impervious sheet 80 is adhered to the sealing material 14.

  The photoelectric conversion element 100 is obtained as described above.

  The present invention is not limited to the above embodiment. For example, in the above embodiment, the input terminal 122, the output terminal 123, the first ground terminal 125, and the second ground terminal 126 are provided on the transparent substrate 11 side in the projecting portion 127 of the circuit board 120. The output terminal 123, the first ground terminal 125, and the second ground terminal 126 may be provided on the surface of the protrusion 127 opposite to the transparent substrate 11.

  Further, in the above-described embodiment, the circuit board 120 is arranged so as to partially overlap the counter substrate 20 when the circuit board 120 and the counter substrate 20 are viewed in the thickness direction of the transparent substrate 11. The whole may be arranged so as to overlap the counter substrate 20. However, in this case, since the counter substrate 20 has the metal substrate 21, the input terminal 122, the output terminal 123, the first ground terminal 125, and the second ground terminal 126 are provided on the surface opposite to the counter substrate 20. To be provided. This is to prevent a short circuit between the input terminal 122, the output terminal 123, the first ground terminal 125, and the second ground terminal 126.

  In the above embodiment, the circuit board 120 is arranged so as to partially overlap the counter substrate 20 when the circuit board 120 and the counter substrate 20 are viewed in the thickness direction of the transparent substrate 11. They may be arranged so as not to overlap the counter substrate 20.

  Further, in the above-described embodiment, it is preferable that the desiccant is provided in the space between the water shield sheet 80 and the transparent substrate 11. In this case, even if moisture penetrates into the space between the water-blocking sheet 80 and the transparent substrate 11, the moisture is absorbed by the desiccant, so that the circuit portion 124 of the circuit board 120 is sufficiently deteriorated by the moisture. Suppressed to. Examples of the material forming the desiccant include silica gel, alumina, and zeolite.

  Furthermore, in the above embodiment, the internal terminal 18a and the external terminal 18b are installed on the transparent conductive layer 12G as an external output part, and the internal terminal 18c is installed on the transparent conductive layer 12H as a cell voltage output part for grounding. The internal terminal 18d is provided on the transparent conductive layer 12E, and the internal terminal 18e and the external terminal 18f are provided on the grounding transparent conductive layer 12I, but these are not always necessary and can be omitted.

  Further, in the above embodiment, the insulating material 33 is provided so as to enter the groove 90 between the transparent conductive layers 12 adjacent to each other between the sealing portion 30 and the transparent substrate 11, but the insulating material 33 is not always necessary. It is not a thing and can be omitted.

  Further, in the above embodiment, the plurality of photoelectric conversion cells 50 are connected in series, but the plurality of photoelectric conversion cells 50 may be connected in parallel.

  Further, in the above embodiment, the number of photoelectric conversion cells 50 is four, but at least one is sufficient and the number is not limited to four.

  Hereinafter, the content of the present invention will be described more specifically with reference to examples, but the present invention is not limited to the following examples.

(Example 1)
First, a laminated body was prepared in which a transparent conductive film made of FTO and having a thickness of 1 μm was formed on a transparent substrate made of glass and having a thickness of 1 mm. Next, as shown in FIG. 4, a groove 90 was formed in the transparent conductive film by a CO ₂ laser (V-460 manufactured by Universal System Co., Ltd.) to form transparent conductive layers 12A to 12J. At this time, the width of the groove 90 was 1 mm. Further, each of the transparent conductive layers 12A to 12C was formed so as to have a quadrangular main body portion having a size of 4.6 cm × 2.0 cm and a protruding portion protruding from one side edge portion of the main body portion. In addition, the transparent conductive layer 12D was formed to have a quadrangular main body of 4.6 cm × 2.1 cm and a protruding portion that protrudes from one side edge of the main body. Regarding the protruding portions 12c of the three transparent conductive layers 12A to 12C among the transparent conductive layers 12A to 12D, the protruding portion 12d protruding from the one side edge portion 12b of the main body portion 12a and the adjacent transparent portion extending from the protruding portion 12d. The conductive layer 12 is configured to include a facing portion 12e facing the body portion 12a. Further, the protrusion 12c of the transparent conductive layer 12D is configured to include only the protrusion 12d protruding from the one side edge 12b of the main body 12a. At this time, the length of the overhang portion 12d in the overhang direction (the direction orthogonal to the X direction in FIG. 2) was 2.1 mm, and the width of the overhang portion 12d was 9.8 mm. The width of the facing portion 12e was 2.1 mm, and the length of the facing portion 12e in the extending direction (direction parallel to the X direction in FIG. 2) was 9.8 mm.

  In addition, the transparent conductive layer 12D is connected to the transparent conductive layer 12H as a cell voltage output portion via the connecting portion 12J to the main body portion 12a. In this way, a transparent conductive layer was formed on one surface of the transparent substrate to obtain a conductive substrate.

  Next, the precursor of the connection terminal 16 was formed on the protrusion 12c of the transparent conductive layers 12A to 12C. The precursor of the connection terminal 16 was formed by applying a silver paste (“GL-6000X16” manufactured by Fukuda Metal Foil & Powder Co., Ltd.) by screen printing and drying.

  Further, a precursor of the current collecting wiring 17 was formed on the connecting portion 12J. The precursor of the current collecting wiring 17 was formed by applying a silver paste by screen printing and drying.

  Further, the precursors of the internal terminals 18a, 18c, 18d, and 18e are provided on the transparent conductive layer 12G as an external output portion, the transparent conductive layer 12H as a cell voltage output portion, the grounding transparent conductive layer 12E, and the grounding transparent conductive layer 12I, respectively. A precursor of the body and the external terminals 18b and 18f was formed. The internal terminal precursor and the external terminal precursor were formed by applying a silver paste by screen printing and drying.

  Further, the precursor of the insulating material 33 was formed so as to enter the first groove 90A formed along the edge of the main body 12a and also cover the edge of the main body 12a. The precursor of the insulating material 33 was formed by applying a paste containing glass frit by screen printing and drying.

  In order to fix the water blocking sheet 80, the transparent conductive layer 12D, the transparent conductive layer 12E, the transparent conductive layer 12F, the transparent conductive layer 12G, and the transparent conductive layer are formed in the same manner as the insulating material 33 so as to surround the insulating material 33. A precursor of an annular sealing material 14 made of glass frit was formed so as to pass over 12H and the transparent conductive layer 12I. Further, at this time, the precursor of the sealing material 14 was formed so that the precursor of the current collecting wiring 17 was disposed inside thereof. The sealing material 14 was formed so that the precursors of the external terminals 18b and 18f were arranged on the outside thereof. The sealing material 14 was formed by applying a paste containing glass frit by screen printing and drying.

  Further, a precursor of the oxide semiconductor layer 13 was formed on the main body 12a of each of the transparent conductive layers 12A to 12D. As a precursor of the oxide semiconductor layer 13, a porous oxide semiconductor layer-forming paste containing titania (“PST-21NR” manufactured by JGC Catalysts & Chemicals Co., Ltd.) was applied three times by screen printing, dried, and then titania. A porous oxide semiconductor layer-forming paste (“PST-400C” manufactured by JGC Catalysts & Chemicals Co., Ltd.) containing the above was applied by screen printing, and then dried.

Next, the precursor of the connection terminal 16, the precursor of the insulating material 33, the precursor of the sealing material 14, the precursor of the internal terminals 18a, 18c, 18d and 18e, the precursor of the external terminals 18b and 18f, and the oxide semiconductor layer. The precursor of 13 is collectively baked at 500 ° C. for 15 minutes, and the connection terminal 16, the current collecting wiring 17, the insulating material 33, the sealing material 14, the internal terminals 18a, 18c, 18d, 18e, the external terminals 18b, 18f, and the oxidation. The semiconductor layer 13 was formed. Thus, on the conductive substrate, the connection terminal 16, the current collecting wiring 17, the insulating material 33, the sealing material 14 for fixing the insulating material 33 and the water blocking sheet 80, the internal terminals 18a, 18c, 18d, 18e, and the external terminals. A structure in which 18b, 18f and the oxide semiconductor layer 13 were formed was obtained. At this time, the dimensions of the internal terminals 18a, 18c, 18d, 18e and the external terminals 18b, 18f, the sealing material 14, and the oxide semiconductor layer 13 were as follows.

Internal terminals 18a, 18c, 18d, 18e and external terminals 18b, 18f: thickness 20 μm, width 2 mm, length 7 mm
Sealing material 14: thickness 50 μm, width 3 mm
Oxide semiconductor layer 13: thickness 13 μm, length 17 mm in X direction in FIG. 2, length 42.1 mm in direction orthogonal to X direction in FIG.

  Next, the structure obtained as described above contains 0.2 mM of a photosensitizing dye consisting of N719, and the solvent is a mixed solvent obtained by mixing acetonitrile and tert-butanol at a volume ratio of 1: 1. After immersing it in the dye solution described above for 24 hours, it was taken out and dried, and the photosensitizing dye was carried on the oxide semiconductor layer.

  Next, on the oxide semiconductor layer, hexylmethylimidazolium iodide 2M, n-methylbenzimidazole 0.3M, and guanidinium thiocyanate 0.1M were added to a solvent containing 3-methoxypropionitrile. The electrolyte was applied and dried to dispose the electrolyte.

  Next, a sealed portion forming body for forming a sealed portion was prepared. As the sealing part forming body, one sheet of sealing resin film made of 8.0 cm × 4.6 cm × 50 μm ethylene-methacrylic acid copolymer (trade name: Nucrel, manufactured by Mitsui DuPont Polychemical Co., Ltd.) is prepared. Then, the resin film for sealing was obtained by forming four square openings. At this time, each opening has a size of 1.7 cm × 4.4 cm × 50 μm, and the width of the annular portion is 2 mm, and the width of the partitioning portion that partitions the inner opening of the annular portion is 2.6 mm. A sealed portion forming body was produced.

  Then, after the sealing portion forming body was superposed on the insulating material 33 on the structure, the sealing portion forming body was heated and melted to adhere to the insulating material 33 on the structure.

  Next, four counter electrodes were prepared. Two of the four counter electrodes were prepared by forming a catalyst layer of platinum having a thickness of 5 nm on a titanium foil of 4.6 cm × 1.9 cm × 40 μm by a sputtering method. The remaining two counter electrodes of the four counter electrodes were prepared by forming a catalyst layer of platinum with a thickness of 5 nm on a titanium foil of 4.6 cm × 2.0 cm × 40 μm by a sputtering method. Further, another sealing part forming body was prepared, and this sealing part forming body was bonded to the surface of the counter electrode facing the structure in the same manner as described above.

  Then, the sealing portion forming body adhered to the structure and the sealing portion forming body adhered to the counter electrode were opposed to each other, and the sealing portion forming bodies were superposed on each other. Then, in this state, the sealing portion forming body was heated and melted while pressurizing the sealing portion forming body.

  Next, a desiccant sheet was attached to the metal substrate of each counter electrode with an adhesive made of a double-sided tape. The dimensions of the desiccant sheet were 1 mm in thickness × 3 cm in length × 1 cm in width, and a Zeo sheet (trade name, manufactured by Shinagawa Kasei Co., Ltd.) was used as the desiccant sheet.

  Further, a low temperature curing type silver paste (manufactured by Fujikura Kasei Co., Ltd., DOTITE D-500) so as to connect the metal substrate of each counter electrode of the photoelectric conversion cells 50B to 50D and the connection terminals on the three transparent conductive layers 12A to 12C, respectively. ) Was applied and cured to form a conductive material 60P. Further, in the photoelectric conversion cell 50A, the conductive material 60P was formed by applying and curing the above-mentioned low temperature curable silver paste so as to connect the counter electrode metal substrate and the conductive material connecting portion on the transparent conductive layer 12E. At this time, the conductive material 60P was formed by curing the above low temperature curable silver paste at 30 ° C. for 12 hours.

  Next, a circuit board was prepared and fixed on the counter substrate 20 of the photoelectric conversion cell 50A. At this time, the circuit board 120 is an insulating substrate made of glass epoxy and having dimensions of 56 cm × 23 cm × 1.6 cm when the circuit board 120 and the counter substrate 20 of the photoelectric conversion cell 50A are viewed in the thickness direction of the transparent substrate 11. Was arranged so as to project outward from the counter substrate 20 by 3 mm. At this time, the projecting portion 127 of the circuit board 120 is provided with the input terminal 122, the output terminal 123, the first ground terminal 125, and the second ground terminal 126 on the transparent substrate 11 side. Specifically, the input terminal 122 faces the internal terminal 18c provided on the transparent conductive layer 12H as a cell voltage output part, and the output terminal 123 is provided on the transparent conductive layer 12G as an external output part. The first ground terminal 125 faces the internal terminal 18d installed on the grounding transparent conductive layer 12E, and the second ground terminal 126 installs on the grounding transparent conductive layer 12I. The circuit board 120 is arranged so as to face the internal terminals 18e and 18f that are formed. The dimensions of the input terminal 122, the output terminal 123, the first ground terminal 125, and the second ground terminal 126 were all 5 mm × 5 mm × 10 μm (thickness). A power supply IC was used as the circuit unit.

  Then, the input terminal 122 and the internal terminal 18c, the output terminal 123 and the internal terminal 18a, the first ground terminal 125 and the internal terminal 18d, and the second ground terminal 126 and the internal terminal 18e were connected by a conductive adhesive.

  Next, butyl rubber (“Aika Melt” manufactured by Aika Kogyo Co., Ltd.) was applied onto the sealing material 14 with a dispenser while heating at 200 ° C. to form a precursor of the adhesive portion. On the other hand, a laminated body prepared by laminating a film (thickness: 50 μm) made of polybutylene terephthalate (PBT) resin film (thickness: 50 μm), an aluminum foil (thickness: 25 μm), and binel (trade name, manufactured by Du Pont) in this order did. Then, the peripheral portion of this laminated body was superposed on the precursor of the adhesive portion 91 and pressed for 10 seconds. In this way, the peripheral edge portion 80a of the water blocking sheet 80 was bonded to the sealing material 14 via the bonding portion 91 having a thickness of 4 mm. The photoelectric conversion element was obtained as described above.

(Comparative Example 1)
Instead of forming the external terminal 18b on the transparent conductive layer 12G as the external output portion, the external terminal 18b is formed on the transparent conductive layer 12H as the cell voltage output portion so as to be arranged outside the sealing material 14, Instead of forming the external terminal 18f on the grounding transparent conductive layer 12I, the external terminal 18f is formed outside the sealing material 14 so as to be arranged on the grounding transparent conductive layer 12E, and the circuit board is fixed on the counter electrode. A photoelectric conversion element was produced in the same manner as in Example 1 except that the water blocking sheet 80 was adhered to the sealing material 14 without doing so.

(Comparative example 2)
Instead of forming the external terminal 18b on the transparent conductive layer 12G as the external output portion, the external terminal 18b is formed on the transparent conductive layer 12H as the cell voltage output portion so as to be arranged outside the sealing material 14, Instead of forming the external terminal 18f on the grounding transparent conductive layer 12I, the external terminal 18f is formed outside the sealing material 14 so as to be arranged on the grounding transparent conductive layer 12E, and the circuit board is fixed on the counter electrode. After adhering the water-blocking sheet 80 to the sealing material 14 without doing so, the input terminal 122 of the circuit board 120 is connected to the external terminal 18b formed on the transparent conductive layer 12H as the cell voltage output section, and the circuit board 120 is connected. A photoelectric conversion element was produced in the same manner as in Example 1 except that the first ground terminal 125 was connected to the external terminal 18f formed on the grounding transparent conductive layer 12E.

<Characteristic evaluation>
(durability)
The photoelectric conversion elements of Example 1, Comparative Example 1 and Comparative Example 2 obtained as described above were placed in a thermostatic chamber (product name “Humilab”, manufactured by GE) having a humidity of 80% at 85 ° C. for 200 hours. After that, the photoelectric conversion element taken out was connected to an electricity storage device, and the voltage of the electricity storage device reached 3.7V (full charge voltage) after reaching 3V (charging start voltage) in a state where white light of 200 lux was irradiated. The time to reach (charging time) was measured. This charging time was used as an index of durability. The results are shown in Table 1. Since the photoelectric conversion element of Comparative Example 1 did not have a circuit board and could not be charged, the charging time was indicated by "-". The light source, illuminance meter, and power storage device used for measuring the charging time are as follows.

Light source: White LED (Product name "LEL-SL5N-F", manufactured by Toshiba Lighting & Technology Corporation)
Illuminance meter: Product name "Digital illuminance meter 51013", Yokogawa meter & Instruments company electricity storage device: Lithium ion capacitor (Product name "LIC1235R3R8406", Taiyo Yuden Co., Ltd.)

(Output voltage)
For each of the photoelectric conversion elements obtained in Example 1, Comparative Example 1 and Comparative Example 2, the output voltage was measured for each illuminance of 10 lux, 100 lux, 200 lux, 500 lux, 1000 lux, 2000 lux, 5000 lux. did. The results are shown in Table 2. The measured output voltage is the output voltage between the external terminal 18b installed on the transparent conductive layer 12G and the external terminal 18f installed on the grounding transparent conductive layer 12I in the first embodiment. In Comparative Example 1, the output voltage is between the external terminal 18b installed on the transparent conductive layer 12H as the cell voltage output section and the external terminal 18f installed on the grounding transparent conductive layer 12E, In Comparative Example 2, the output voltage is between the output terminal 123 of the circuit board 120 and the external terminal 18f provided on the grounding transparent conductive layer 12E.

  From the results shown in Table 1, it was found that the photoelectric conversion element of Example 1 completed charging in a considerably shorter time than the photoelectric conversion element of Comparative Example 2. Further, from the results shown in Table 2, in the photoelectric conversion elements of Example 1 and Comparative Example 2, the output voltage was stable regardless of the illuminance of the incident light, whereas in the photoelectric conversion element of Comparative Example 1, , When the illuminance of the incident light is low, the output voltage is low, and when the illuminance of the incident light is high, the output voltage is high, and the output voltage is the illuminance of the light incident on the photoelectric conversion element. Was not stable by.

  From the above, it was confirmed that the photoelectric conversion element of the present invention has excellent durability even in a high humidity environment and can output a stable voltage regardless of the illuminance of incident light.

11 ... Transparent substrate 11a ... One surface 12 ... Transparent conductive layer 12G ... Transparent conductive layer (external output part)
12H ... Transparent conductive layer (cell voltage output part)
14 ... Sealing material 20 ... Counter substrate 30 ... Sealing part 40 ... Electrolyte 50, 50A-50D ... Photoelectric conversion cell 80 ... Water-blocking sheet 100 ... Photoelectric conversion element 120 ... Circuit board 121 ... Insulating substrate 122 ... Input terminal 123 ... Output Terminal 124 ... Circuit part 127 ... Projection part

Claims (3)

A transparent substrate,
At least one photoelectric conversion cell provided on one surface of the transparent substrate;
A water-blocking sheet provided on the one surface of the transparent substrate and covering the at least one photoelectric conversion cell;
An annular sealing material that is provided on the one surface of the transparent substrate so as to surround the at least one photoelectric conversion cell, and that connects the peripheral portion of the water-impervious sheet and the transparent substrate,
A circuit board provided in a space between the water-blocking sheet and the transparent substrate,
A cell voltage output section which is provided on the transparent substrate and outputs a voltage from the at least one photoelectric conversion cell to the circuit board;
An external output unit which is provided on the one surface of the transparent substrate and outside the at least one photoelectric conversion cell, across the annular sealing material, and which outputs the voltage output from the circuit substrate to the outside. ,
The circuit board is
An insulating substrate,
An input terminal provided on the insulating substrate and connected to the cell voltage output unit,
An output terminal provided on the insulating substrate and connected to an inner external output portion inside the sealing material of the external output portion,
A photoelectric conversion element, comprising: a circuit portion provided on the insulating substrate and configured to output a voltage, which is input from the input terminal, to the output terminal as a constant voltage. The photoelectric conversion cell,
A transparent conductive layer provided on the one surface of the transparent substrate,
A counter substrate facing the transparent conductive layer,
The photoelectric conversion element according to claim 1, wherein the circuit board is arranged so as to at least partially overlap the counter substrate when the counter substrate and the circuit board are viewed in the thickness direction of the transparent substrate. The counter substrate has a metal substrate,
The circuit board has a protrusion that protrudes from the counter substrate when the counter substrate and the circuit substrate are viewed in the thickness direction of the transparent substrate,
The input terminal and the output terminal are provided on the protrusion,
The input terminal and the cell voltage output section are connected by a first conductive member,
The photoelectric conversion element according to claim 2, wherein the output terminal and the inner external output section of the external output section are connected by a second conductive member.

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