Photovoltaic Module

Abstract

A photovoltaic module that can be provided with high flexibility without reducing conversion efficiency is provided. 1 and 2, a photovoltaic module 1 is generally configured to include a plurality of photovoltaic elements 2 each having at least one cell 20, and a flexible conductive member 3 that electrically connects the electrode terminals of adjacent photovoltaic elements 2. This photovoltaic module 1 can be highly flexible without reducing conversion efficiency.

Description

[Technical Field]

[0001] The present invention relates to a photovoltaic module. [Background technology]

[0002] As a conventional technology, a solar cell module is known that includes a plurality of power generating elements, a flexible substrate that electrically connects the plurality of power generating elements, a first transparent resin that individually protects the plurality of power generating elements, and a second transparent resin that covers the first transparent resin and the flexible substrate (see, for example, Patent Document 1).

[0003] This solar cell module has a recess and a reflector provided between a plurality of power generating elements, and a flexible substrate and a second transparent resin interposed between the recess and the reflector. The solar cell module can be bent starting from the recess. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-226101 Summary of the Invention [Problem to be solved by the invention]

[0005] In conventional solar cell modules, the rigidity of the recessed portion is low when using only a flexible substrate, so the two power generating elements wrapped in a first transparent resin are further coated with a second transparent resin to increase rigidity. Therefore, in conventional solar cell modules, the second transparent resin, which is not actually necessary, is placed on the light receiving surface, which reduces the conversion efficiency of converting light energy into electrical energy.

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a photovoltaic module that can be provided with high flexibility without reducing conversion efficiency. [Means for solving the problem]

[0007] One aspect of the present invention provides a photovoltaic module comprising a plurality of photovoltaic elements each having at least one cell, and a flexible conductive member that electrically connects the electrode terminals of adjacent photovoltaic elements. [Effects of the Invention]

[0008] According to the present invention, high flexibility can be achieved without reducing conversion efficiency. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing an example of a photovoltaic module according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing an example of a photovoltaic module according to an embodiment taken along line II-II in FIG. 1, viewed from the direction of the arrows. [Figure 3] FIG. 3 is a diagram showing an example of a bent photovoltaic module according to an embodiment. [Figure 4] FIG. 4 is a diagram showing an example of a photovoltaic module including a photovoltaic element having a plurality of cells according to a modified example. [Figure 5] FIG. 5 is a diagram showing an example in which a photovoltaic module according to an embodiment is wrapped around a finger or wrist. DETAILED DESCRIPTION OF THE INVENTION

[0010] (Summary of the embodiment) The photovoltaic module according to the embodiment is generally configured to include a plurality of photovoltaic elements each having at least one cell, and a flexible conductive member that electrically connects the electrode terminals of adjacent photovoltaic elements.

[0011] This photovoltaic module connects adjacent photovoltaic elements with a conductive member that can be easily bent, so it can have high flexibility without reducing conversion efficiency, compared to when adjacent photovoltaic elements are connected by providing a structure that covers the photovoltaic elements.

[0012] [Embodiment Mode] (Photovoltaic Module 1 Overview) FIG. 1 is a diagram showing an example of a photovoltaic module according to an embodiment. FIG. 2 is a cross-sectional view showing an example of a photovoltaic module according to an embodiment taken along line II-II in FIG. 1, viewed from the direction of the arrow. FIG. 3 is a diagram showing an example of a bent photovoltaic module according to an embodiment. FIG. 4 is a diagram showing an example of a photovoltaic module including a photovoltaic element having a plurality of cells according to a modified example. FIG. 5 is a diagram showing an example of a photovoltaic module according to an embodiment wrapped around a finger or wrist. Note that in each of the figures according to the embodiments described below, the ratios and shapes between figures may differ from the actual ratios and shapes.

[0013] As shown in Figures 1 and 2, the photovoltaic module 1 is generally composed of a plurality of photovoltaic elements 2 each having at least one cell 20, and a flexible conductive member 3 that electrically connects the electrode terminals of adjacent photovoltaic elements 2.

[0014] 2, the photovoltaic element 2 is generally configured to include a substrate 21, a first electrode terminal 22 and a second electrode terminal 23 provided on the substrate 21, a photoelectric conversion layer 24 provided on the first electrode terminal 22 and the second electrode terminal 23 and converting the light energy of incident light 4 into electrical energy, an upper electrode 25 provided on the photoelectric conversion layer 24 and electrically connected to the second electrode terminal 23, and a sealing portion 26 that seals at least the photoelectric conversion layer 24 and the upper electrode 25. The conductive member 3 electrically connects one of the first electrode terminal 22 and the second electrode terminal 23 of one adjacent photovoltaic element 2 to the other of the first electrode terminal 22 and the second electrode terminal 23 of the other adjacent photovoltaic element 2.

[0015] 2, as an example, when one adjacent photovoltaic element 2 is the left photovoltaic element 2 and the other adjacent photovoltaic element 2 is the right photovoltaic element 2, the conductive member 3 electrically connects the second electrode terminal 23 of one adjacent photovoltaic element 2 to the first electrode terminal 22 of the other adjacent photovoltaic element 2. In this case, the photovoltaic module 1 has multiple photovoltaic elements 2 connected in series. Note that in the photovoltaic module 1, the conductive member 3 may electrically connect the first electrode terminal 22 of one adjacent photovoltaic element 2 to the second electrode terminal 23 of the other adjacent photovoltaic element 2.

[0016] Furthermore, the photovoltaic module 1 may electrically connect the first electrode terminals 22 or the second electrode terminals 23 of adjacent photovoltaic elements 2. In this case, the photovoltaic module 1 has a plurality of photovoltaic elements 2 connected in parallel.

[0017] An organic solar cell, a silicon solar cell, a compound solar cell, an organic-inorganic hybrid solar cell, etc. can be used as the photovoltaic element 2. One example of the photovoltaic element 2 of this embodiment is a perovskite solar cell.

[0018] Perovskite solar cells are organic-inorganic hybrid solar cells made of materials with a perovskite structure, and are lightweight and highly flexible. Perovskite solar cells are generally configured, for example, to include a photoelectric conversion layer 24 having a perovskite layer, a hole transport layer, and an electron transport layer; a first electrode terminal 22 and an upper electrode 25 disposed on either side of the photoelectric conversion layer 24; and a second electrode terminal 23 electrically connected to the upper electrode 25. When exposed to light, perovskite solar cells are configured such that electrons and holes are generated in the perovskite layer, the electrons are transported to the negative electrode via the electron transport layer, and the holes are transported to the positive electrode terminal via the hole transport layer, generating a current due to the movement of charges, thereby generating electricity.

[0019] (Configuration of Cell 20) 1 and 2, the cell 20 has a rectangular shape and is generally configured to include a first electrode terminal 22, a second electrode terminal 23, a photoelectric conversion layer 24, an upper electrode 25, and a sealing portion 26. The shape of the cell 20 is not limited to a rectangular shape.

[0020] The photovoltaic element 2 of the present embodiment has one cell 20, but is not limited to this. As a modification, when the photovoltaic element 2 has a plurality of cells 20, the adjacent first electrode terminals 22 and second electrode terminals 23 of the cells 20 are shared, as shown in Fig. 4 as an example. When the photovoltaic element 2 has a plurality of cells 20, the strip-shaped cells 20 are arranged at equal intervals.

[0021] (Configuration of substrate 21) The substrate 21 is, for example, a film substrate formed using PET (Polyethylene Terephthalate), which has excellent flexibility and transparency, but is not limited to this. When the photovoltaic element 2 has a plurality of cells 20, the plurality of cells 20 share the substrate 21.

[0022] As described above, perovskite solar cells have excellent flexibility, and therefore the substrate 21 of the cell 20 also has excellent flexibility, making it easy to bend the cell 20 while preventing performance degradation.

[0023] (Configuration of the first electrode terminal 22 and the second electrode terminal 23) The first electrode terminal 22 and the second electrode terminal 23 are formed of a substantially transparent material so that light 4 incident from the substrate 21 side is incident on the photoelectric conversion layer 24, as shown in FIG. 2, for example. Such materials include, for example, metal oxides, transparent conductive polymers, and transparent conductive inks. Examples of metal oxides include indium tin oxide (ITO) and indium zinc oxide (IZO). Examples of transparent conductive polymers include PEDOT / PSS (poly-3,4-ethylenedioxythiophene / polysulfonic acid). Examples of transparent conductive inks include those containing carbon nanotubes and silver nanofibers in a binder.

[0024] The first electrode terminal 22 and the second electrode terminal 23 in this embodiment are transparent electrodes using indium tin oxide (ITO) as an example, but are not limited to this.

[0025] The first electrode terminal 22 and the second electrode terminal 23 are formed by using a laser to separate a thin film formed on the substrate 21. In the photovoltaic element 2, the surfaces of the photoelectric conversion layer 24 facing the first electrode terminal 22 and the second electrode terminal 23, and the boundary surface between the first electrode terminal 22 and the second electrode terminal 23 and the substrate 21 serve as light-receiving surfaces 27.

[0026] 2, the first electrode terminal 22 and the second electrode terminal 23 are partially exposed to the outside of the sealing portion 26. The conductive member 3 is electrically connected to the exposed first electrode terminal 22 and second electrode terminal 23.

[0027] The second electrode terminal 23 is configured to be electrically connected to an upper electrode 25 formed on the photoelectric conversion layer 24, as will be described later.

[0028] One of the first electrode terminal 22 and the second electrode terminal 23 is a positive electrode terminal and the other is a negative electrode terminal. In this embodiment, the first electrode terminal 22 is a positive electrode terminal and the second electrode terminal 23 is a negative electrode terminal.

[0029] (Configuration of photoelectric conversion layer 24) As described above, the photoelectric conversion layer 24 is configured to convert the optical energy of the light 4 incident from the substrate 21 side into electrical energy and output it from the first electrode terminal 22 and the second electrode terminal 23.

[0030] (Configuration of upper electrode 25) The upper electrode 25 is formed of a conductive material such as gold, silver, aluminum, or copper. As an example, the upper electrode 25 is formed of copper, but is not limited to this. As an example, the upper electrode 25 may be configured as a transparent electrode when light is introduced from the upper electrode 25 side. As shown in FIG. 2, the upper electrode 25 has a protrusion 250 that is electrically connected to the second electrode terminal 23.

[0031] (Configuration of sealing portion 26) The sealing portion 26 is, for example, a PET film. The sealing portion 26 has an adhesive 260 and seals the upper electrode 25 and the like.

[0032] (Configuration of conductive member 3) The conductive member 3 is a flexible substrate, a conductive cloth, or the like. In this embodiment, the conductive member 3 is, for example, a conductive cloth. The conductive member 3 can be, for example, a metal knitted cloth made of knitted metal fibers, a conductive cloth made of woven metal knitted cloth, a conductive cloth made of resin fibers with a metal layer, or a conductive cloth made of knitted fibers (innermost tube·PET / intermediate layer·Cu / outer skin·Ni). For example, the conductive member 3 has a thickness of about 0.3 mm, but is not limited to this. It is desirable that the conductive cloth be stretchable.

[0033] The conductive member 3 is electrically connected to the first electrode terminal 22 and the second electrode terminal 23 by, for example, laser-applied solder, conductive paste, pellets, etc. Alternatively, the conductive member 3 may be electrically connected to the first electrode terminal 22 and the second electrode terminal 23 by using a connector.

[0034] As shown in Fig. 1, the conductive member 3 is configured so that the width L is wider than the distance R between the photovoltaic elements 2. In Fig. 1, the distance R is the distance between the photovoltaic elements 2, but it may be the length in the short direction of the conductive member. The conductive member 3 does not electrically connect the photovoltaic elements 2 over only a portion of the width L, as in the case of connection by electric wire, but rather forms multiple electrical paths across the width L. Therefore, even if a portion of the conductive member 3 peels off, the electrical paths are unlikely to be interrupted.

[0035] As an example, as shown in FIG. 5, the conductive member 3 is flexible and can be wrapped around a small diameter cylinder or a surface with a small curvature such as a finger 5 or a wrist 6.

[0036] As a modified example, the conductive member 3 may be attached so as to be electrically connected to the upper electrode 25 through an opening provided in the sealing portion 26 .

[0037] (Effects of the embodiment) The photovoltaic module 1 according to this embodiment can have high flexibility without reducing conversion efficiency. Specifically, the photovoltaic module 1 connects adjacent photovoltaic elements 2 with an easily bendable conductive member 3, and therefore can have high flexibility without reducing conversion efficiency compared to a case in which adjacent photovoltaic elements are connected by providing a structure that covers the photovoltaic elements.

[0038] In the photovoltaic module 1, the photovoltaic elements 2 are perovskite solar cells that are highly flexible and do not easily lose conversion efficiency even when bent, so not only the conductive member 3 but also the photovoltaic elements 2 themselves are easier to bend than other solar cells. Therefore, in the photovoltaic module 1, the conductive member 3 and photovoltaic elements 2 are easy to bend, and the photovoltaic module 1 can be placed on a surface with a small curvature while suppressing a decrease in conversion efficiency.

[0039] The photovoltaic module 1 has excellent flexibility and can be placed on a surface with a small curvature as a wearable device, a sensor, or the like.

[0040] In the photovoltaic module 1, when the conductive member 3 is a conductive cloth, multiple electrical paths are formed across the width L, so that the electrical paths are less likely to be interrupted even if a portion is peeled off, compared to electrical paths based on wiring. Therefore, the photovoltaic module 1 is less likely to suffer from poor electrical continuity due to bending.

[0041] Although the embodiments and modifications of the present invention have been described above, these embodiments and modifications are merely examples and do not limit the scope of the invention as claimed. These novel embodiments and modifications can be embodied in various other forms, and various omissions, substitutions, modifications, etc. can be made without departing from the spirit of the present invention. Furthermore, not all combinations of features described in these embodiments and modifications are necessarily essential to solving the problems of the invention. Furthermore, these embodiments and modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0042] REFERENCE SIGNS LIST 1...photovoltaic module, 2...photovoltaic element, 3...conductive member, 4...light, 5...finger, 6...wrist, 20...cell, 21...substrate, 22...first electrode terminal, 23...second electrode terminal, 24...photoelectric conversion layer, 25...upper electrode, 26...sealing portion, 27...light-receiving surface, 250...protrusion, 260...adhesive

Claims

1. a plurality of photovoltaic devices each having at least one cell; a flexible conductive member that electrically connects the electrode terminals of the adjacent photovoltaic elements; A photovoltaic module comprising:

2. The photovoltaic element is a substrate; a first electrode terminal and a second electrode terminal provided on the substrate; a photoelectric conversion layer provided on the first electrode terminal and the second electrode terminal and converting light energy of incident light into electrical energy; an upper electrode provided on the photoelectric conversion layer and electrically connected to the second electrode terminal; and a sealing portion sealing at least the photoelectric conversion layer and the upper electrode. Equipped with the conductive member electrically connects one of the first electrode terminal and the second electrode terminal of one of the adjacent photovoltaic elements to the other of the first electrode terminal and the second electrode terminal of the other adjacent photovoltaic element. The photovoltaic module of claim 1 .

3. The conductive member is a conductive cloth. The photovoltaic module of claim 2 .

4. The photovoltaic device is a perovskite solar cell. The photovoltaic module of claim 2 .

5. the conductive member has a width greater than the distance between the photovoltaic elements; 5. A photovoltaic module according to any one of claims 1 to 4.

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