JP6916162B2 - Electric module and manufacturing method of electric module - Google Patents

Description

The present invention relates to an electric module and a method for manufacturing an electric module. This application claims priority based on Japanese Patent Application No. 2016-028968 filed in Japan on February 18, 2016 and Japanese Patent Application No. 2016-161884 filed in Japan on August 22, 2016. Is used here.

In recent years, solar cells have attracted attention as a clean energy power generation device, and silicon-based solar cells and dye-sensitized solar cells are being developed. Dye-sensitized solar cells have high photoelectric conversion efficiency, are inexpensive, and are easy to mass-produce. Therefore, their structures and manufacturing methods have been widely studied.

In the above-mentioned dye-sensitized solar cell and other electric modules that require sealing, when a plurality of cells are arranged side by side in the same plane, for example, between adjacent cells, the upper electrode of the first cell is used. And the lower electrode of the second cell are electrically connected, and in order to seal an element such as an electrolyte between the electrodes, "sealing material / conductive material (for example, conducting wire, conductive paste, etc.) / It forms the structure of a "sealing material".

For example, in Patent Document 1, photoelectric conversion elements provided with transparent electrodes, counter electrodes, and a sealing insulating portion for sealing and insulating these electrodes are provided side by side in the same plane. The module is disclosed. In this photoelectric conversion module, in order to electrically connect adjacent photoelectric conversion elements, a part of the transparent electrode member of the first photoelectric conversion element and a part of the counter electrode member of the second photoelectric conversion element. Are arranged so as to face each other, and a conductive material is arranged between the first and second photoelectric conversion elements. As a result, a series structure is formed between the plurality of cells.

Conventional electric modules such as the photoelectric conversion element disclosed in Patent Document 1 use a metal wire or the like as a conductive material, and therefore, when cutting a cell by a laser, ultrasonic fusion, or the like, the cell is cut. There is a problem that it is difficult to cut the conductive material and it takes time and effort to cut the cell.
As one method for solving the above-mentioned problems, a method of making an electrical connection by using a conductive paste having a conductive filler in the adhesive is known.

Japanese Unexamined Patent Publication No. 2001-357897

However, the conventional conductive paste does not have sufficient conductive performance to secure the electrical connection between the photoelectric conversion elements in the electric module. Specifically, the conventional conductive paste has a problem that the followability to a base material such as a film is low, and when the conductive paste is peeled off from the base material, the contact between the conductive paste and the base material cannot be established. Therefore, the electric module using the conductive paste has a problem that the quality stability is low.

The present invention has been made in view of the above circumstances, and provides an electric module capable of ensuring ease of cutting and high stability of quality, and a method for manufacturing the electric module.

The electric module according to the present invention is a conductive material that is in contact with the first electrode on the first base material and the second electrode on the second base material, and is provided between the first electrode and the second electrode. The conductive material includes conductive particles that enable conduction between the first electrode and the second electrode, and some or all of the conductive particles include the first electrode and the second electrode. It is characterized in that it is in contact with both of the above and bites into at least one of the first electrode and the second electrode.

According to the above configuration, for example, when a conductive material (or a conductive paste before curing as a conductive material) is arranged between the electrodes constituting the electric module, the conductive particles are dispersed in the extending direction of the electrodes. NS. As a result, the conductive particles in the extending direction of the electrodes are relatively soft and easy to cut.
Further, in the thickness direction between the electrodes, the contact between the electrodes is easily and surely obtained by the portion of the conductive particles that bites into at least one of the first electrode and the second electrode, and the electrodes are electrically connected to each other. Further, since the conductive particles "bite" into at least one of the first electrode and the second electrode, the bonding strength between the conductive particles and the electrode is increased, and the electrode is less likely to be peeled off from the conductive material containing the conductive particles. The relative positional relationship with the conductive material is less likely to shift, and the thickness dimension between the electrodes is kept constant for a long period of time. As a result, the conductive performance of the electric module is surely maintained, and the quality is satisfactorily stabilized.

In the electric module according to the present invention, it is preferable that some or all of the conductive particles penetrate the first electrode and / or one of the second electrodes.

According to the above configuration, when the conductive particles penetrate the first electrode and / or one of the second electrodes, the conductive particles come into contact with the electrodes over the entire thickness direction, so that the conductive particles and the electrodes are in contact with each other. Better continuity. As a result, the conductive performance of the electric module is more reliably maintained, and the quality is better and more stable.

In the electric module according to the present invention, the partial or all conductive particles are in contact with both the first electrode and the second electrode, and either or both of the first base material and the second base material. It is preferable to bite into one side.

According to the above configuration, when the conductive particles are in contact with both the first electrode and the second electrode, both the contact point between the first electrode and the conductive particle and the contact point between the second electrode and the conductive particle are formed. Contact points between the electrodes can be obtained more easily and reliably, and the electrodes can be conducted with each other. Further, since at least a part of the conductive particles "bites" into both or one of the first base material and the second base material, the area and thickness dimension in which the conductive particles and the electrodes are in contact with each other become larger, and the conductivity becomes larger. The bonding strength between the particles and the electrodes is further increased. As a result, the conductive performance of the electric module is more reliably maintained, and the quality is better and more stable.

In the electric module according to the present invention, the distance between the first electrode and the second electrode is preferably 30% or more and 250% or less of the average particle size of the group of conductive particles.

According to the above configuration, the first electrode and the first electrode so that a part or all of the conductive particles are in contact with both the first electrode and the second electrode and bite into at least one of the first electrode and the second electrode. The distance between the two electrodes is suitable. Therefore, the binder-only portion between the conductive particles in the extending direction of the electrode is relatively soft and easy to cut. In addition, the conductive performance of the electric module is surely maintained, and the quality is good and stable.

In the electric module according to the present invention, the conductive material may further contain an auxiliary conductive material having a diameter smaller than the distance between the first electrode and the second electrode in the thickness direction.

According to the above configuration, since the auxiliary conductive substance is arranged in the gap between the conductive particles between the electrodes, the contact point between the electrodes can be obtained more easily, and the electrodes can conduct better. As a result, the conductive performance of the electric module is more reliably maintained, and the quality is better and more stable.

In the electric module according to the present invention, the first electrode or the second electrode may contain a photosensitizing dye.

According to the above configuration, electrons are passed from the photosensitizing dye that has been stimulated by being irradiated with light to the first electrode or the second electrode, and electrons are further transferred to the other electrodes via the conductive particles. Passed.
A dye-sensitized electric module based on such a principle is obtained, its conductive performance is more reliably maintained, and its quality is better and more stable.

The method for manufacturing an electric module according to the present invention is a method for manufacturing an electric module, in which the first electrode and the second electrode are opposed to each other at an arbitrary distance, and the first electrode and the second electrode are opposed to each other. The first step of arranging at least the conductive particles and the first base material and the second base material are pressed so as to be close to each other, and the first base material and the second base material are attached to each other. It is characterized by including a second step of matching.

According to the above configuration, in the first step, the first electrode and the second electrode are arranged to face each other at an arbitrary distance, and in the second step, the first base material and the second base material are attached via the conductive material. Will be combined.
According to the above-mentioned steps, for example, when the conductive paste (conductive material) of the present invention is arranged between the electrodes constituting the electric module, the conductive particles are dispersed in the extending direction of the electrodes. As a result, the distance between the conductive particles in the extending direction of the electrodes becomes relatively soft, so that an electric module that is easy to cut can be obtained.
Further, in the second step, when the first base material and the second base material are bonded to each other, the first base material and the second base material are pressed so as to be close to each other, so that the thickness direction between the electrodes In, the conductive particles bite into at least one of the first electrode and the second electrode. The contact between the electrodes is easily and surely obtained, the electrodes are conductive to each other, and the conductive particles "bite" into at least one of the first electrode and the second electrode, so that the bonding strength between the conductive particles and the electrodes is increased. Therefore, the conductive performance of the electric module is surely maintained, and the quality is good and stable.

In the method for manufacturing an electric module according to the present invention, in the second step, the distance between the first electrode and the second electrode is set to 30% or more and 250% or less of the average particle size of the group of conductive particles. Is preferable.

According to the above configuration, by setting the distance between the first electrode and the second electrode to be 30% or more and 250% or less of the average particle diameter of the group of conductive particles, some or all of the conductive particles can be combined with the first electrode. The distance between the first electrode and the second electrode is suitable so that it is in contact with both the second electrode and bites into at least one of the first electrode and the second electrode. Therefore, the portion of only the binder between the conductive particles in the extending direction of the electrode becomes relatively soft, and an electric module that is easy to cut can be obtained. In addition, the conductive performance is surely maintained, and a stable electric module with good quality can be obtained.

In the method for manufacturing an electric module according to the present invention, in the second step, the first base material and the second base material are pressed with a force of 0.4 N or more per conductive particle so as to be close to each other. It is preferable to do so.

According to the above configuration, since the semiconductor electrode and the counter electrode, the first base material and the second base material are appropriately extruded outward in the thickness direction of the conductive particles by both ends in the thickness direction of the conductive particles, the conductive particles The bonding strength between the electrode and the first electrode or the second electrode is increased, and the conduction between the electrodes is stabilized.

According to the present invention, an electric module that can be easily electrically cut, can easily cut the conductive material between the first electrode and the second electrode, and can conduct electricity between the electrodes with high stability can be obtained. Be done.

It is a top view which shows the dye-sensitized solar cell which is one Embodiment of this invention. It is a figure which shows the dye-sensitized solar cell which is one Embodiment of this invention, and is the cross-sectional view which shows a part of the cross section seen by the arrow BB shown in FIG. It is a figure which shows the dye-sensitized solar cell which is one Embodiment of this invention, and is the cross-sectional view seen by the arrow AA shown in FIG. It is a figure which shows the 1st modification of the dye-sensitized solar cell which is one Embodiment of this invention It is sectional drawing which shows a part of. It is a figure which shows the 2nd modification of the dye-sensitized solar cell which is one Embodiment of this invention It is sectional drawing which shows a part of. It is a figure which shows the 3rd modification of the dye-sensitized solar cell which is one Embodiment of this invention It is sectional drawing which shows a part of. It is a figure which shows the 4th modification of the dye-sensitized solar cell which is one Embodiment of this invention, and is the cross-section which is seen at the position corresponding to the line BB shown in FIG. It is sectional drawing which shows a part of. It is a figure for demonstrating the manufacturing method of the dye-sensitized solar cell which is one Embodiment of this invention, and is the sectional view of one of the bonded base materials. It is a figure for demonstrating the manufacturing method of the dye-sensitized solar cell which is one Embodiment of this invention, and is the sectional view of the other bonded base material. It is a figure for demonstrating the manufacturing method of the dye-sensitized solar cell which is one Embodiment of this invention, and is the cross-sectional view which shows the state of bonding the bonded base materials to each other.

Hereinafter, the electric module 1 and the method for manufacturing the electric module according to the present invention will be described with reference to the drawings. The drawings used in the following description are schematic, and the length, width, thickness ratio, etc. are not always the same as the actual ones and can be changed as appropriate. Further, the configuration and structure of the electric module 1 are not limited to the shown length, width, thickness ratio, and the like.

<Electric module>
As shown in FIGS. 1 to 3, in the dye-sensitized solar cell (electric module) 1A, the semiconductor electrode (first electrode) 7 and the counter electrode (second electrode) 8 are arranged to face each other via the conductive material 6. It is an electric module.

In the following, a dye-sensitized solar cell 1A will be described as an example of an embodiment of the electric module 1 according to the present invention, but the present embodiment will be described between the first base material 2 and the second base material 4. Sealing of the formed plurality of cells C and each cell C, C. ..., It can be applied to various electric modules that require electrical series connection or parallel connection between Cs.

Specifically, the dye-sensitized solar cell 1A includes a first base material 2, a second base material 4, a semiconductor electrode 7, a counter electrode 8, an electrolyte 9, and a conductive material 6. ..

The semiconductor electrode 7 includes a transparent conductive film 3 laminated on the first base material 2, and a porous semiconductor layer 10 laminated on the transparent conductive film 3.
The counter electrode 8 includes a counter conductive film 5 laminated on the second base material 4 and a catalyst layer 11 laminated on the counter conductive film 5.

Encapsulants 12 and 12 are arranged on both sides of the conductive material 6 of the dye-sensitized solar cell 1A. The conductive material 6 and the sealing material 12 bond the electrodes (that is, between the semiconductor electrode 7 and the counter electrode 8). On the other hand, in the direction intersecting the extending direction of the conductive material 6, the insulating and bonded portions are insulated and bonded by means such as ultrasonic fusion (hereinafter, the insulated portion is referred to as "insulating portion 13"). In this way, the cells C each having the semiconductor layer 10 are liquid-tightly sealed. Then, the conductive particles 20 contained in the conductive material 6 form a gap in the thickness direction between the semiconductor electrode 7 and the counter electrode 8, and the electrolyte 9 is sealed in the gap.

In the dye-sensitized solar cells 1A and 1B, the conductive material 6 is in direct contact with the transparent conductive film 3 and the opposed conductive film 5 constituting the semiconductor electrode 7 and the counter electrode 8. A plurality of patterning portions 25 insulated by laser irradiation or the like are provided at predetermined positions of the transparent conductive film 3 and the opposed conductive film 5.

The transparent conductive film 3 and the opposed conductive film 5 between adjacent cells C and C are divided into a plurality of sections by the patterning portion 25, and a pattern of the plurality of transparent conductive films 3 and the opposed conductive film 5 is formed. In each of the partitioned cells C, the opposed conductive film 5 constituting the counter electrode 8 of the first cell C1 and the transparent conductive film 3 constituting the semiconductor electrode 7 of the second cell C2 adjacent to the first cell C1. Is electrically connected by the conductive material 6. As a result, the first cell C1 and the second cell C2 are connected in series.

The materials of the first base material 2 and the second base material 4 are not particularly limited, and examples thereof include insulators such as resins, semiconductors, metals, and glass. Examples of the resin include poly (meth) acrylic acid ester, polycarbonate, polyester, polyimide, polystyrene, polyvinyl chloride, and polyamide. From the viewpoint of producing a thin and light flexible dye-sensitized solar cell 1A, the base material is preferably made of a transparent resin, and more preferably a polyethylene terephthalate (PET) film or a polyethylene naphthalate (PEN) film. .. The material of the first base material 2 and the material of the second base material 4 may be different.

The types and materials of the transparent conductive film 3 and the opposed conductive film 5 are not particularly limited, and the conductive films used in known dye-sensitized solar cells can be applied. For example, a thin film composed of a metal oxide can be applied. Can be mentioned. Examples of the above-mentioned metal oxide include tin-doped indium oxide (ITO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (ATO), indium oxide / zinc oxide (IZO), gallium-doped zinc oxide (GZO), and the like. can.

The semiconductor layer 10 is made of a material capable of receiving electrons from the adsorbed photosensitizing dye, and is usually preferably porous. The material constituting the semiconductor layer 10 is not particularly limited, and known materials of the semiconductor layer 10 can be applied, and examples thereof include metal oxide semiconductors such as titanium oxide, zinc oxide, and tin oxide.
The photosensitizing dye supported on the semiconductor layer 10 is not particularly limited, and examples thereof include known dyes such as organic dyes and metal complex dyes. Examples of the above-mentioned organic dye include coumarin-based, polyene-based, cyanine-based, hemicyanine-based, and thiophene-based. As the metal complex dye, for example, a ruthenium complex or the like is preferably used.

The material constituting the catalyst layer 11 is not particularly limited, and known materials can be applied, for example, carbons such as platinum and carbon nanotubes, and poly (3,4-ethylenedioxythiophene) -poly (styrene sulfonate). Examples thereof include conductive polymers such as acid) (PEDOT / PSS).

The electrolyte 9 is not particularly limited, and an electrolyte used in a known dye-sensitized solar cell can be applied. Examples of the electrolyte 9 include an electrolytic solution in which iodine and sodium iodide are dissolved in an organic solvent.

A known photosensitizing dye (not shown) is adsorbed on the surface of the semiconductor layer 10 in contact with the electrolyte 9, including the inside of the porous material.

The conductive material 6 is arranged between a plurality of semiconductor layers 10 extending parallel to each other and extending in one direction, and is in contact with the semiconductor electrode 7 on the first base material 2 and the counter electrode 8 on the second base material 4. It is provided between the semiconductor electrode 7 and the counter electrode 8.
By leveling or pressurizing the conductive material 6 in the coating or arrangement of the conductive material 6, the conductive particles 20 are easily arranged in a single layer without overlapping in the thickness direction. Therefore, as shown in FIG. 3, the conductive particles 20 of the conductive material 6 are arranged in a single layer in the thickness direction between the transparent conductive film 3 and the opposing conductive film 5 by a leveling operation such as pressurization. There is. The conductive particles 20 do not necessarily have to be arranged in a single layer between the transparent conductive film 3 and the opposed conductive film 5.

Specifically, the conductive material 6 contains at least conductive particles 20. In the present embodiment, the conductive material 6 further contains a binder 18, and the conductive paste is cured. Hereinafter, in a broad sense, the conductive paste is also interpreted as the conductive material 6. The conductive material 6 may have reduced fluidity or low fluidity.

As the binder 18, a polymer binder used for forming a semiconductor layer of a known dye-sensitized solar cell can be applied, and examples thereof include ethyl cellulose, nitrocellulose, polyacrylic acid ester, and polyethylene glycol. Be done.
As the binder 18, one type may be used alone, or two or more types may be used in combination, and even if the binder 18 is not a polymer, the fluidity may be appropriately suppressed.

The conductive particles 20 are substances that are dispersed in the conductive paste and enable the electrodes of the dye-sensitized solar cell 1A to conduct with each other. The conductive particles 20 may be conductive particles themselves such as metal particles, or may be particles formed of, for example, a metal layer having a conductive surface at least.

The conductive particles 20 make it possible to conduct electricity between the semiconductor electrode 7 and the counter electrode 8. At least some or all of the conductive particles 20 are in contact with both the semiconductor electrode 7 and the counter electrode 8 and bite into at least one of the semiconductor electrode 7 and the counter electrode 8, as shown in FIGS. 2 and 3. ..

As shown in FIG. 2, some or all of the conductive particles 20 penetrate both or one of the semiconductor electrode 7 and the counter electrode 8 and either or both of the first base material 2 and the second base material 4. It is preferable to bite into one side. Incidentally, in FIG. 2, all of the conductive particles 20 penetrate both the semiconductor electrode 7 and the counter electrode 8 and bite into both the first base material 2 and the second base material 4.
With such an arrangement, the surface of the conductive particles 20 and the inner wall of the semiconductor electrode 7 and the counter electrode 8 where the conductive particles 20 penetrate are surely in contact with each other, and both ends of the conductive particles 20 in the thickness direction are the first base material. It is in a state of being embedded inside 2 and the second base material 4.

The dye-sensitized solar cell 1B shown in FIG. 4 is a first modification of the dye-sensitized solar cell 1A.
As shown in FIG. 4, a part or all of the conductive particles 20 are in contact with both the semiconductor electrode 7 and the counter electrode 8, and both ends of the conductive particles 20 in the thickness direction are both the semiconductor electrode 7 and the counter electrode 8 or It may be arranged inside either one.
With such an arrangement, the surface of the conductive particles 20 and the surfaces of the semiconductor electrode 7 and the counter electrode 8 in the portion where the conductive particles 20 are embedded are surely in contact with each other.

The shape of the conductive particles 20 shown in FIGS. 2 and 4 is an example, and the shape of the conductive particles 20 is particularly limited as long as the conductive particles 20 can be arranged between the electrodes as described above and play the role of a spacer. Not done. Examples of the shape of such conductive particles include a polygonal shape, an elliptical shape, a needle shape, a star shape, a substantially spherical shape, and the like.

The dye-sensitized solar cell 1C shown in FIG. 5 is a second modification of the dye-sensitized solar cell 1A.
While the conductive particles 20 of the dye-sensitized solar cells 1A and 1B have a polygonal shape, as shown in FIG. 5, the conductive particles 20 of the dye-sensitized solar cell 1C are, for example, spherical. Part or all of the spherical conductive particles 20 are in contact with both the semiconductor electrode 7 and the counter electrode 8, and both ends of the conductive particles 20 in the thickness direction bite into both or one of the semiconductor electrode 7 and the counter electrode 8. I'm out. That is, both ends of a part or all of the conductive particles 20 in the thickness direction are located inside both or one of the semiconductor electrode 7 and the counter electrode 8.

Even in the configuration of the dye-sensitized solar cell 1C, the surface of the conductive particles 20 and the surfaces of the semiconductor electrode 7 and the counter electrode 8 in the portion where the conductive particles 20 are embedded are surely in contact with each other. Further, since both ends of the conductive particles 20 in the thickness direction are fixed at predetermined positions by both or either of the semiconductor electrode 7 and the counter electrode 8, the conductive particles can be bent even when the entire dye-sensitized solar cell 1C is bent. The position of 20 is not easily displaced, and the conductivity between the conductive particles 20 and the semiconductor electrode 7 and the counter electrode 8 is reliably maintained.

The dye-sensitized solar cell 1D shown in FIG. 6 is a third modification of the dye-sensitized solar cell 1A.
The conductive particles 20 of the dye-sensitized solar cell 1D are, for example, spherical like the conductive particles 20 of the dye-sensitized solar cell 1C. As shown in FIG. 6, a part or all of the spherical conductive particles 20 are in contact with both the semiconductor electrode 7 and the counter electrode 8. At least the semiconductor electrode 7 and the counter electrode 8 are extruded outward in the thickness direction by both ends of the spherical conductive particles 20 in the thickness direction. In the configuration illustrated in FIG. 6, the first base material 2 and the second base material 4 are also extruded outward in the thickness direction of the conductive particles 20.

Like the configuration of the dye-sensitized solar cell 1D, the semiconductor electrode 7 and the counter electrode 8 are extruded outward in the thickness direction by both ends in the thickness direction of the conductive particles 20, for example, the dye-sensitized solar cell 1C. When the conductive particles 20 of the dye-sensitized solar cell 1D are harder than the conductive particles 20 of the above, the semiconductor electrode 7 of the dye-sensitized solar cell 1D is compared with the semiconductor electrode 7 of the dye-sensitized solar cell 1C and the counter electrode 8. It is conceivable that the counter electrode 8 is soft or has high elasticity.

Further, as will be described later in the method for manufacturing the dye-sensitized solar cell 1A, when manufacturing each of the dye-sensitized solar cells of the present embodiment, the first base material 2 and the second base material 4 are placed in the thickness direction. They are pasted together at a predetermined interval. At this time, when the distance between the first base material 2 and the second base material 4 is narrowed and the conductive particles 20 are bonded so as to be crushed, when the shape of the conductive particles 20 is restored after the bonding, the sealing material is used. When the conductive material 12 or the conductive material 6 is in an uncured state, the semiconductor electrode 7 and the counter electrode 8 may be pushed outward in the thickness direction by both ends of the conductive particles 20 in the thickness direction. For example, the first base material 2 and the second base material 20 are crushed so that the conductive particles 20 are crushed by 10% or more of the average particle size, that is, the thickness dimension of the conductive particles 20 is 90% or less of the average particle size. When the materials 4 are bonded together, the semiconductor electrode 7, the counter electrode 8, the first base material 2 and the second base material 4 are appropriately directed outward in the thickness direction of the conductive particles 20 by both ends in the thickness direction of the conductive particles 20. It is thought that it will be pushed out to. As described above, when the conductive particles 20 are crushed so that the thickness dimension of the conductive particles 20 is 90% or less of the average particle size, the first base material is formed from the outside of the first base material 2 and the second base material 4. It is considered that the force applied to the 2 and the second base material 4 is preferably 0.4 N or more per conductive particle 20.

Although spherical conductive particles 20 are illustrated in FIGS. 5 and 6, the shape of the conductive particles 20 is not particularly limited as described above, and the shape of the conductive particles 20 is not particularly limited, and a polygonal shape, an elliptical shape, a needle shape, a star shape, and the like. It may have a shape other than that. Even when the conductive particles 20 having a shape other than the spherical shape are used, as shown in FIG. 5, both ends of a part or all of the conductive particles 20 in the thickness direction are the semiconductor electrode 7 and the counter electrode 8. The conductive particles 20 are located in the inner side of both or either one, or at least the semiconductor electrode 7 and the counter electrode 8 are formed at both ends of the conductive particles 20 in the thickness direction as shown in FIG. It can be extruded outward in the thickness direction.

Even in the configuration of the dye-sensitized solar cell 1D, the surface of the conductive particles 20 and the surfaces of the semiconductor electrode 7 and the counter electrode 8 in the portion where the conductive particles 20 are embedded are surely in contact with each other. Further, since the semiconductor electrode 7 and the counter electrode 8 are in contact with the entire both ends of the conductive particle 20 in the thickness direction, the contact area between the conductive particle 20 and the semiconductor electrode 7 and the counter electrode 8 is a dye-sensitized solar cell 1A, 1B. , 1C is enlarged, and the conductivity between the conductive particles 20 and the semiconductor electrode 7 and the counter electrode 8 is more reliably maintained. Further, since both ends of the conductive particles 20 in the thickness direction are fixed at predetermined positions by both or either of the semiconductor electrode 7 and the counter electrode 8, the conductive particles can be bent even when the entire dye-sensitized solar cell 1D is bent. The position of 20 is not easily displaced, and the conductivity between the conductive particles 20 and the semiconductor electrode 7 and the counter electrode 8 is reliably maintained.

The average particle size of the conductive particles 20 is, for example, 5 μm or more and 500 μm or less.
When the conductive paste contains a conductive substance in addition to the conductive particles 20, the conductive particles 20 having a desired average particle diameter are 1% by mass or more of the plurality of conductive substances contained in the conductive paste. It is preferably contained in an amount of 10% by mass or more, more preferably 40% by mass or more, still more preferably 70% by mass or more. This makes it easier to keep the distance between the electrodes constant.

The distance between the semiconductor electrode 7 and the counter electrode 8 is appropriately set in consideration of physical characteristics such as elasticity of the conductive particles 20 used, and the degree of variation in shape and particle size. The distance between the semiconductor electrode 7 and the counter electrode 8 is, for example, preferably 30% or more and 250% or less, more preferably 40% or more and 150% or less, and 50% or less of the average particle size of the group of conductive particles 20. It is more preferably% or more and 120%, and particularly preferably 60% or more and 90% or less. As a result, as shown in FIG. 3, both ends of the conductive particles 20 in the thickness direction are easily arranged inside the semiconductor electrode 7 and the counter electrode 8. In particular, when the distance between the semiconductor electrode 7 and the counter electrode 8 is 60% or more and 90% or less of the average particle diameter of the group of the conductive particles 20, the thickness interval between the semiconductor electrode 7 and the counter electrode 8 is the group of the conductive particles 20. As shown in FIG. 2, the conductive particles 20 penetrate the semiconductor electrode 7 and the counter electrode 8 and easily bite into the first base material 2 and the second base material 4.

The material of the conductive particles 20 is not particularly limited as long as it has a hardness sufficient to bite into the first base material 2 and the second base material 4, has conductivity, or can impart conductivity. Examples thereof include metal particles such as gold, silver, copper, chromium, titanium, platinum, nickel, tin, zinc, lead, tungsten, iron and aluminum. Further, particles made of alloys and compounds containing these metals, particles made of conductive resin, and carbon-based particles such as carbon black can be mentioned. Further, examples thereof include those in which resin particles are coated with a conductive metal such as electroless nickel.

In the present embodiment, from the viewpoint that the conductive particles 20 are appropriately dispersed in the conductive paste, 99.9% by mass to 30% by mass of the binder 18 is contained with respect to the conductive particles 20 of 0.1% by mass to 80% by mass. It is preferable that the particles are used. When the conductive paste contains the binder 18 and the conductive particles 20 in such a mass ratio, the conductive particles 20 are appropriately dispersed in the conductive paste as described above, and the hardness of the conductive paste is distributed to the electrodes. It will be a convenient degree. Further, in the conductive paste and the conductive material 6, the conductive particles 20 suitable for stable conduction between the electrodes can be held, and the conductive material 6 can be easily insulated or cut by ultrasonic waves or the like. , Conductive particles 20 are included. The conductive paste and the conductive material 6 may contain an appropriate amount of a thickener in order to increase the viscosity or prevent the conductive particles 20 made of metal particles from settling.

The dye-sensitized solar cell 1A'shown in FIG. 7 is a fourth modification of the dye-sensitized solar cell 1A.
As shown in FIG. 7, the conductive material 6 preferably includes an auxiliary conductive substance 21 in addition to the binder 18 and the conductive particles 20. For example, if the auxiliary conductive substance 21 is in the form of particles, it has a diameter dimension smaller than the distance between the electrodes in the thickness direction when it is included in the conductive material 6 and arranged between the electrodes. Note that FIG. 7 illustrates a configuration in which the auxiliary conductive substance 21 is provided as a modification of the dye-sensitized solar cell 1A shown in FIGS. 1 to 3, but the dye-sensitized solar cell 1B shown in FIGS. 4 to 6 is illustrated. The same configuration can be applied to, 1C, and 1D.

The average particle size of the auxiliary conductive substance 21 is preferably 80% or less, and is 50% or less, for example, 80% or less of the average particle size of the conductive particles 20 for the purpose of interposing in the gap between the conductive particles 20 in the conductive material 6. Is more preferable, and 30% or less is further preferable. As a result, the above-mentioned object is achieved, and the conductivity of the conductive material 6 is further enhanced, so that the electrodes are electrically satisfactorily and stably conducted.

The auxiliary conductive substance 21 may be any as long as it has conductivity and does not interfere with the conductivity of the conductive particles 20, and examples thereof include particulate matter and fibers having a diameter smaller than that of the conductive particles 20.
As the material of the auxiliary conductive substance 21, metals such as gold, silver, copper, chromium, titanium, platinum, nickel, tin, zinc, lead, tungsten, iron and aluminum, compounds containing these metals, conductive resins, or Examples thereof include those made of a carbon material such as carbon black. It may be the same substance as the conductive particles 20.

When the auxiliary conductive substance 21 is fibrous, the fiber diameter of the auxiliary conductive substance 21 is preferably 45% or less, more preferably 30% or less, based on the average particle diameter of the group of the conductive particles 20. , 15% or less is more preferable. The aspect ratio of the fiber length of the auxiliary conductive substance 21 is, for example, about 2 or more and 500 or less. The fiber diameter and aspect ratio can be appropriately adjusted so as not to impair the conductivity of the conductive particles 20.
The shape and size of the auxiliary conductive substance 21 may be uniform or non-uniform, and is not particularly limited.

Further, the conductive paste may contain an adhesive, an adhesive, an organic solvent, a thickener, and the like in addition to the binder 18, the conductive particles 20, and the auxiliary conductive substance 21. This adhesive is a substance having a function of maintaining a state in which the electrodes of the dye-sensitized solar cells 1A, 1B, 1C, 1D, 1A'exemplified in FIGS. 1 to 7 are arranged to face each other at a predetermined interval. Is. Specific examples of the adhesive include, but are not limited to, a resin material containing at least one resin of a thermoplastic resin, a thermosetting resin, and an ultraviolet curable resin.

Examples of the resin material of the adhesive include vinyl acetate resin emulsion type adhesive, ethylene / vinyl acetate copolymer resin, EVA (ethylene-vinyl acetate-vinyl chloride ternary copolymer) type emulsion type adhesive, and α-. Olefin (isobutene-maleic anhydride resin) adhesive, acrylic resin emulsion adhesive, styrene / butadiene rubber latex adhesive, vinyl acetate resin solvent adhesive, acrylic resin solvent adhesive, vinyl chloride Resin-based solvent-based adhesive, chloroprene rubber-based solvent-based adhesive, chloroprene rubber-based solvent-based mastic type adhesive, nitrile rubber-based solvent-based adhesive, recycled rubber-based solvent-based styrene butadiene rubber (SBR) Solvent type adhesive, urethane resin adhesive, silicone resin adhesive, modified silicone resin adhesive, epoxy / modified silicone resin adhesive, acrylic resin adhesive (SGA) adhesive, starch type Examples thereof include adhesives, polymer cement mortars, epoxy resin mortars, silylated urethane resin adhesives, hot melt type adhesives and the like.

Further, as described above, as long as it has a function of maintaining a state in which the electrodes are arranged so as to face each other at a predetermined interval, a highly viscous adhesive material can be used as the adhesive. Examples of the pressure-sensitive adhesive material having high viscosity include, but are not limited to, rubber-based, acrylic-based, silicone-based, and urethane-based materials. Specific examples thereof include natural rubber, acrylic acid ester copolymer, silicone rubber, urethane resin and the like.

The organic solvent contained in the conductive paste is an auxiliary medium for maintaining the dispersed state of the conductive particles and the binder resin. Examples of such an organic solvent include, but are not limited to, water, ethyl acetate, ester-based, alcohol-based and ketone-based solvents, tetrahydrofuran, hexane, aromatic solvents and the like.

<Manufacturing method of electric module>
Next, an embodiment of the method for manufacturing the electric module 1 according to the present invention will be described by taking as an example a method for manufacturing the dye-sensitized solar cell 1A (hereinafter, also simply referred to as “manufacturing method”).

The manufacturing method of the present embodiment is the manufacturing method of the dye-sensitized solar cell 1A, in which the semiconductor electrode 7 and the counter electrode 8 are opposed to each other at an arbitrary distance between the semiconductor electrode 7 and the counter electrode 8. It includes at least a first step of arranging the conductive particles 20 and a second step of pressing the first base material and the second base material so as to bring them close to each other and sticking them together. Hereinafter, each step will be specifically described.

[First step]
First, a predetermined position for forming a cell on the first substrate 2 which is continuously conveyed in a predetermined direction P by using a known method for manufacturing a dye-sensitized solar cell using a roll-to-roll method. The transparent conductive film 3 is formed on the surface, then the semiconductor layer 10 is formed at a predetermined position, the sealing materials 12 are formed on both sides (that is, the periphery) of the semiconductor layer 10, and then the electrolyte 9 is laminated. As a result, as shown in FIG. 8, a bonded base material 31 provided with the semiconductor electrode 7 and the sealing material 12 and having a gap S formed at an appropriate position is obtained. The predetermined direction P may be freely set in consideration of manufacturing convenience and the like, and may be, for example, a direction parallel to the extending direction of the conductive material 6.

Next, using a known method for manufacturing a dye-sensitized solar cell, the opposed conductive film 5 is formed at a predetermined position for forming a cell on the second base material 4 which is continuously conveyed in a predetermined direction P. After that, the catalyst layer 11 is formed at a predetermined position. As a result, as shown in FIG. 9, a bonded base material 32 provided with the counter electrode 8 is obtained.

Next, as shown in FIG. 10, at least the binder 18 and the conductive particles 20 from the conductive paste supply unit 34 are contained in the gap (between the first electrode and the second electrode) S of the bonded base material 31. It is filled with the conductive paste to be used as the conductive material 6. Actually, the conductive paste may be filled slightly thicker than a predetermined thickness in consideration of the fact that the sealing material 12, the wiring material, and the like are crushed and spread in the second step described later.

[Second step]
Subsequently, as shown in FIG. 10, the semiconductor layer 10 of the bonded base material 31 and the catalyst layer 11 of the bonded base material 32 are opposed to each other, and the bonded base material 31 and the bonded base material 32 are brought close to each other. The bonded base materials 31 and 32 are arranged along the thickness direction at predetermined intervals in the thickness direction, and are bonded to the bonded base material (first base material) 31 by using a pair of rollers 41 and 42. The combined base material (second base material) 32 is pressed so as to be closer to each other. The bonding base material 31 and the bonding base material 32 are bonded together by irradiating the UV irradiation unit 46 with ultraviolet rays UV vertically downward and curing the sealing material 12 made of an ultraviolet curing resin. After that, with the passage of time, the fluidity of the conductive paste and the like decrease, and the paste is appropriately cured. As a result, the dispersion of the conductive particles 20 in the conductive material 6 is stabilized.

In the second step, the distance between the semiconductor electrode 7 and the counter electrode 8, that is, the thickness interval is preferably 30% or more and 250% or less, and 40% or more and 150% or less of the average particle diameter of the group of conductive particles 20. More preferably, it is more preferably 50% or more and 120%, and particularly preferably 60% or more and 90% or less. Further, it is preferable to appropriately adjust the vertical distance between the pair of rollers 41, 42, the pressing force, and the like so that the distance between the semiconductor electrode 7 and the counter electrode 8 is the above-mentioned condition. By adjusting the distance between the semiconductor electrode 7 and the counter electrode 8 in this way, when the bonded base materials 31 and 32 are pressed against each other and bonded to each other, at least a part of the conductive particles 20 is the semiconductor electrode 7 and the facing electrode 7. It penetrates the electrode 8 and easily bites into both the first base material 2 and the second base material 4.

By the above first step and second step, the dye-sensitized solar cell 1A shown in FIGS. 1 and 3 can be obtained.
In the method for manufacturing the dye-sensitized solar cells 1B, 1C, and 1D shown in FIGS. 4 to 6, the distance between the semiconductor electrode 7 and the counter electrode 8 is set in the thickness direction of at least a part of the conductive particles 20 in the second step. The method is the same as that of the dye-sensitized solar cell 1A described above, except that both ends are appropriately adjusted so as to be arranged in the semiconductor electrode 7 and the counter electrode 8. The method for producing the dye-sensitized solar cell 1A'shown in FIG. 7 is the same as the method for producing the dye-sensitized solar cell 1A described above, except that the conductive paste contains the auxiliary conductive substance 21.

In the electric module 1 illustrated in the dye-sensitized solar cells 1A, 1B, 1C, 1D, 1A'described above and the manufacturing method thereof, at least between the semiconductor electrode 7 and the counter electrode 8 constituting the electric module 1. When the conductive paste containing the binder 18 and the conductive particles 20 is arranged, the conductive particles 20 are dispersed in the extending direction of the semiconductor electrode 7 and the counter electrode 8. Then, the first base material 2 and the second base material 4 provided with the semiconductor electrode 7 and the counter electrode 8 are pressed and equalized so as to be close to each other, leveled, and bonded to each other so that the conductive particles 20 are on the same surface (that is, of the electrodes). One side) Easy to arrange in a single layer on top. Therefore, when the conductive material 6 obtained by solidifying the conductive paste is arranged between the electrodes, a single number of conductive particles 20 (that is, in a single layer) are interposed in the gap S in the thickness direction between the electrodes. .. As a result, according to the electric module 1 and the method for manufacturing the electric module 1, the portion of only the binder 18 and the adhesive between the conductive particles 20 in the extending direction of the electrode is relatively soft, and the electric module 1 that is easy to cut can be obtained. ..

Further, in the electric module 1 and its manufacturing method, the semiconductor electrode 7 is formed by a portion of the conductive particles 20 that bites into at least one of the semiconductor electrode 7 and the counter electrode 8 in the thickness direction between the semiconductor electrode 7 and the counter electrode 8. A contact point between the counter electrode 8 and the counter electrode 8 is easily and surely obtained, and the electrodes are electrically connected to each other. Further, the conductive particles 20 "bite" into at least one of the semiconductor electrode 7 and the counter electrode 8 to increase the bonding strength between the conductive particles 20 and these electrodes, and the electrodes are formed from the conductive material 6 containing the conductive particles 20. It becomes difficult to peel off, the relative positional relationship between the electrode composed of the semiconductor electrode 7 and the counter electrode 8 and the conductive material 6 does not easily shift, and the thickness dimension between the electrodes is kept constant for a long period of time. Therefore, according to the electric module 1 and the manufacturing method thereof, the conductive performance of the electric module 1 can be reliably maintained, and the quality of the electric module 1 can be satisfactorily stabilized. That is, it is possible to obtain an electric module 1 which is easy to electrically cut, can easily cut the conductive material 6 between the semiconductor electrode 7 and the counter electrode 8, and can conduct electricity between the electrodes with high stability. can.

Like the dye-sensitized solar cells 1A, 1B, 1C, 1D, 1A', at least some of the conductive particles 20 "bite" into both or one of the first base material 2 and the second base material 4. As a result, the thickness dimension in which the conductive particles 20 are in contact with the semiconductor electrode 7 and the counter electrode 8 becomes larger, and the bonding strength between the conductive particles 20 and these electrodes is further increased. Further, as in the dye-sensitized solar cells 1A, 1B, 1C, 1D, 1A', some or all of the conductive particles 20 penetrate the semiconductor electrode 7 and / or the counter electrode 8. Since the conductive particles 20 are in contact with the semiconductor electrode 7 and the counter electrode 8 over the entire thickness direction, the conduction between the conductive particles 20 and the semiconductor electrode 7 and the counter electrode 8 can be improved. With such a configuration, the conductive performance of the dye-sensitized solar cells 1A, 1B, 1C, 1D, 1A'is more reliably maintained, and the quality of the dye-sensitized solar cells 1A, 1B, 1C, 1D, 1A' is improved. It can be stabilized well.

Further, according to the electric module 1 and its manufacturing method, the distance between the semiconductor electrode 7 and the counter electrode 8 is set to 30% or more and 250% or less of the average particle diameter of the group of conductive particles 20, so that a part or all of the distance is set. The distance between the semiconductor electrode 7 and the counter electrode 8 can be optimized so that the conductive particles 20 are in contact with both the semiconductor electrode 7 and the counter electrode 8 and bite into at least one of the semiconductor electrode 7 and the counter electrode 8. .. Therefore, the portion of only the binder 18 between the conductive particles 20 in the extending direction of the electrode can be relatively soft and easy to cut.

Like the dye-sensitized solar cell 1A', the conductive material 6 further contains the auxiliary conductive substance 21, so that the auxiliary conductive substance 21 is arranged in the gap between the conductive particles 20 between the electrodes, and the contacts between the electrodes are formed. It can be formed more easily, and the electrodes can be made more conductive with each other. As a result, the conductive performance of the dye-sensitized solar cell 1A'can be more reliably maintained, and the quality of the dye-sensitized solar cell 1A' can be stabilized more satisfactorily.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various aspects of the present invention are described within the scope of the claims. It can be transformed and changed.

For example, the conductive material 6 itself plays the role of the sealing material 12, and may also serve as the sealing material 12.

In the present embodiment, the conductive paste and the conductive material 6 in which the conductive particles 20 are directly dispersed in the binder 18 have been described as examples, but the conductive particles 20 may be an appropriate auxiliary material (not shown). They may be indirectly held by the adhesive via a sealing material and integrated. Further, when the above-mentioned auxiliary material does not exist, the binder 18 may be omitted. As the non-conductive material that can constitute such an auxiliary material, for example, a resin material containing at least one kind of resin such as a thermoplastic resin, a thermosetting resin, and an ultraviolet curable resin, or a fiber material constituting a known fiber. , Cellulose, polyvinyl alcohol and the like. Further, as the auxiliary material described above, a known sealing material used for an electric module such as a solar cell may be used other than those exemplified above.

Next, an example carried out to support the effect of the electric module and the method for manufacturing the electric module according to the present invention will be described. The present invention is not limited to the following examples.

A dye-sensitized solar cell 1D (see FIG. 6) was manufactured using a PET film as the first base material 2 and the second base material 4.

(Example 1)
When manufacturing the dye-sensitized solar cell 1D, micropearl: AU100 (average diameter: 100 μm, manufacturer: Sekisui Chemical Industry Co., Ltd.) is used as the conductive particles 20, and a compression tester (model number: DUH-W201, manufacturer: stock) is used. Shimadzu Seisakusho Co., Ltd.) applied a force of 0.4 N to each of the conductive particles 20 so as to crush the conductive particles 20 from the outside in the thickness direction of the first base material 2 and the second base material 4. In the obtained dye-sensitized solar cell 1D, as shown in FIG. 6, the semiconductor electrode 7 and the counter electrode 8 are extruded outward in the thickness direction of the conductive particles 20 by both ends in the thickness direction of the conductive particles 20, and the conductive particles. Convex portions were formed on the first base material 2 and the second base material 4 of the wiring portion in which 20 was arranged. This convex portion has a shape substantially similar to the ball chipping at both ends in the thickness direction of the substantially spherical micropearl which is the conductive particle 20, and rises from the respective surfaces of the first base material 2 and the second base material 4. It is the part that is. Further, in the present embodiment, the crushing direction is rearward (that is, the upper side in FIG. 6) as compared with the front side (that is, the lower side in FIG. 6 and the side of the first base material 2). Therefore, the dimension of the conductive particles 20 extruded outward in the thickness direction of the second base material 4) became larger.
In this way, when the first base material 2 and the second base material 4 are bonded together by applying a force of 0.4 N, the bonding strength between the conductive particles 20 and the semiconductor electrode 7 or the counter electrode 8 can be increased. Seem.

(Example 2)
A dye-sensitized solar cell 1D was manufactured in the same manner as in Example 1 except that a needle-shaped copper powder (average size of the longest part: 90 μm) was used as the conductive particles 20. Also in the dye-sensitized solar cell 1D of Example 2, convex portions were formed on the first base material 2 and the second base material 4 of the wiring portion in which the conductive particles 20 were arranged. In the convex portion, it was confirmed that both ends of the conductive particles 20 in the thickness direction bite into the semiconductor electrode 7 and the counter electrode 8 and also bite into the first base material 2 and the second base material.

(Comparison example)
In contrast to Examples 1 and 2 described above, Micropearl (average diameter: 100 μm, manufacturer: Sekisui Chemical Co., Ltd.) having a flexible core as conductive particles 20 when manufacturing the dye-sensitized solar cell 1D, That is, a similar product of the micropearl (average diameter: 100 μm, manufacturer: Sekisui Chemical Co., Ltd.), which differs only in the core from the micropearl used in Example 1, was used, and the first base material 2 and the above-mentioned compression tester were used. The conductive particles 20 were bonded together by applying a force of 0.065 N so as to crush the conductive particles 20 from the outside in the thickness direction of the second base material 4. In the obtained dye-sensitized solar cell 1D, no convex portion was formed.
In this way, when the first base material 2 and the second base material 4 are bonded together by applying a force of 0.065 N, the conductive particles 20 in the wiring portion where the conductive particles 20 are arranged and the semiconductor electrode 7 or the counter electrode 8 There is a possibility that there is a portion where the conductive particles are not bonded, and it is considered difficult to increase the bonding strength between the conductive particles 20 and the semiconductor electrode 7 or the counter electrode 8.

1 ... Electric module, 1A, 1B, 1C, 1D, 1A', 1B ... Dye-sensitized solar cell (electric module), 2 ... First base material, 4 ... Second base material, 6 ... Conductive material, 7 ... Semiconductor Electrode (first electrode), 8 ... counter electrode (second electrode), 18 ... binder, 20 ... conductive particles, 21 ... auxiliary conductive material

Claims (9)

A conductive material that is in contact with the first electrode on the first base material and the second electrode on the second base material and is provided between the first electrode and the second electrode is provided.
The conductive material contains conductive particles that enable conduction between the first electrode and the second electrode.
Some or all of the conductive particles are in contact with both the first electrode and the second electrode, and bite into at least one of the first electrode and the second electrode .
An electric module in which at least the first electrode and the second electrode are extruded outward in the thickness direction of the conductive particles by both ends in the thickness direction of a part or all of the conductive particles. The electric module according to claim 1, wherein some or all of the conductive particles penetrate the first electrode and / or one of the second electrodes. Claim that some or all of the conductive particles are in contact with both the first electrode and the second electrode, and bite into both or one of the first base material and the second base material. 1 or the electric module according to claim 2. The electric module according to any one of claims 1 to 3, wherein the distance between the first electrode and the second electrode is 30% or more and 250% or less of the average particle diameter of the group of conductive particles. The electric module according to any one of claims 1 to 4, wherein the conductive material further contains an auxiliary conductive material having a diameter smaller than the thickness distance between the first electrode and the second electrode. .. The electric module according to any one of claims 1 to 5, wherein the first electrode or the second electrode contains a photosensitizing dye. The method for manufacturing an electric module according to any one of claims 1 to 6.
The first step of arranging at least the conductive particles between the first electrode and the second electrode by facing the first electrode and the second electrode at an arbitrary distance.
A method for manufacturing an electric module, comprising a second step of pressing the first base material and the second base material so as to bring them close to each other and bonding the first base material and the second base material to each other. The method for manufacturing an electric module according to claim 7, wherein the second step is a distance between the first electrode and the second electrode of 30% or more and 250% or less of the average particle size of the group of conductive particles. 7. How to manufacture electrical modules.

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