Solar cell modules

Abstract

The present invention provides a solar cell module that can suppress a decrease in power generation efficiency even when the angle of incidence of light deviates from the direction normal to the panel surface. [Solution] In one aspect of the present invention, a solar cell module is provided, comprising a film substrate 11, a solar cell 10 provided on the film substrate 11 that converts light energy into electrical energy, and a diffuser plate 3 that diffuses light on the light incidence side of the solar cell 10, wherein the light-receiving surface of the solar cell 10 includes a surface having at least two different normal vectors.

Description

Technical Field

[0001] The present invention relates to a solar cell module.

Background Art

[0002] Conventionally, a solar cell module in which a plurality of solar cells are arranged and connected in series is known (see, for example, Patent Document 1).

[0003] The solar cell module described in Patent Document 1 has a configuration in which a plurality of solar cells are connected in a corrugated shape with unevenness. According to Patent Document 1, it is said that with this configuration, a large output power can be obtained with the same occupied area as in the conventional case.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the solar cell module described in Patent Document 1, depending on the light irradiation direction, shadows may occur on the solar cells due to the uneven shape, and conversely, the power generation efficiency may decrease.

[0006] An object of the present invention is to provide a solar cell module having a large output voltage with respect to the occupied area and capable of suppressing a decrease in power generation efficiency due to the occurrence of shadows.

Means for Solving the Problems

[0007] One aspect of the present invention provides a solar cell module according to the following [1] to [5] in order to achieve the above object.

[0008] [1] A solar cell module comprising a film substrate, a solar cell provided on the film substrate that converts light energy into electrical energy, and a diffuser plate that diffuses the light on the light incidence side of the solar cell, wherein the light-receiving surface of the solar cell includes a surface having at least two different normal vectors. [2] The solar cell module according to [1], wherein the film substrate is formed in a bellows shape with alternating mountain folds and valley folds, and a plurality of solar cells are mounted on the slopes between the mountain folds and valley folds of the film substrate. [3] The solar cell module according to [1], wherein the film substrate is formed having a curved surface curved with a predetermined curvature, and the solar cells are mounted on the curved surface of the film substrate, curved with the same curvature as the curved surface. [4] The solar cell module according to [3], wherein a plurality of the solar cells are mounted in sections on the curved surface of the film substrate. [5] The solar cell module according to any one of [1] to [4] above, wherein the diffuser plate is provided at a position higher than the top of the light-receiving surface of the solar cell on the light-incident side. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a solar cell module that has a large output voltage relative to the occupied area and can suppress the decrease in power generation efficiency due to shading. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1(a) is a perspective view showing a solar cell module according to the first embodiment of the present invention, and Figure 1(b) is a cross-sectional view taken along line A-A in Figure 1(a). [Figure 2] Figure 2 is a top view showing a film solar cell according to the first embodiment of the present invention. [Figure 3] Figure 3 is a magnified partial view of a part of a film solar cell according to the first embodiment of the present invention. [Figure 4]Figure 4(a) is a cross-sectional view taken along line B-B in Figure 2, and Figure 4(b) is a cross-sectional view taken along line C-C in Figure 2. [Figure 5] Figure 5 is a top view showing a modified example of a solar cell module according to the first embodiment of the present invention. [Figure 6] Figure 6 is a partially enlarged view of a part of a film solar cell according to a second embodiment of the present invention. [Figure 7] Figure 7 is a partially enlarged view of a part of a film solar cell according to the third embodiment of the present invention. [Modes for carrying out the invention]

[0011] (Summary of the embodiment) The solar cell module according to this embodiment comprises a film substrate, a solar cell provided on the film substrate that converts light energy into electrical energy, and a diffuser plate that diffuses light on the light incidence side of the solar cell, wherein the light-receiving surface of the solar cell is composed of a surface having at least two different normal vectors.

[0012] This solar cell module has a high output voltage relative to its occupied area and can suppress the decrease in power generation efficiency caused by shading.

[0013] [Embodiment] (Overview of solar cell modules) Figure 1(a) is a perspective view showing a solar cell module according to the first embodiment of the present invention, and Figure 1(b) is a cross-sectional view taken along line A-A in Figure 1(a).

[0014] The solar cell module 1 comprises a film solar cell 1A in which solar cells 10 that convert light energy into electrical energy are provided on a film substrate 11, a frame 2 that surrounds the film solar cell 1 on all four sides, and a diffuser plate 3 attached to the frame 2 that diffuses light on the side of the film solar cell 1 where light is incident.

[0015] The frame body 2 is a square-ring-shaped outer frame member, and supports the film solar cell 1A and the diffusion plate 3 at a predetermined interval. For example, in the present embodiment, the diffusion plate 3 is fixed to the opening edge on one side of the frame body 2 (the side opposite to the film base material 11 of the film solar cell 1), and the end of the film solar cell 1A is fixed to the opening edge on the other side (the film base material 11 side of the film solar cell 1). Thereby, the diffusion plate 3 is provided at a position higher than the top of the light-receiving surface of the solar cell 10 on the light-incorporating side. The material and properties of the frame body 2 are not particularly limited. For example, a typical example of the frame body 2 is a molded product made of aluminum. Further, in order to enable the film solar cell 1A to efficiently incorporate light, a reflective sheet may be attached to the inner wall surface.

[0016] Also, in the present embodiment, the diffusion plate 3 is provided only in one opening of the frame body 2, but it may be provided in both openings of the frame body 2. In this case, the light taken in from the film base material 11 side of the frame body 2 can also be diffused.

[0017] The diffusion plate 3 is made of a high light-transmittance polycarbonate resin, or transparent acrylic or the like, and fine irregularities such as embossing are provided on the surface. Further, instead of providing fine irregularities on the surface, a diffusing material may be dispersed inside. Also, as a modified example, instead of the diffusion plate 3, a light diffusion film may be provided on the light-receiving surface of the solar cell 10. In this case, the frame body 2 can be omitted.

[0018] The film solar cell 1A typically has a plurality (10 in the present embodiment) of solar cells 10 arranged on a film base material 11 and sealed with a sealing material 12. In the examples shown in FIGS. 1(a) and 1(b), the plurality of solar cells 10 are connected in series, and the generated electric power can be supplied to an external device through electrodes 14 connected to both ends thereof.

[0019] In the film solar cell 1A, the cross-sectional shape of the solar cell 10 in the short-side direction is formed in a bellows-like manner by alternately folding mountain folds and valley folds along the long sides between each solar cell 10. This creates an uneven surface between the solar cells 10. The uneven surface of the film solar cell 1A formed by multiple solar cells 10 can be maintained by arranging the multiple solar cells 10 on a film substrate 11 and sealing them with a common sealing material 12. A film solar cell 1 in which multiple solar cells 10 are arranged to form an uneven surface in this way can have its dimensions in the planar direction reduced, making it possible to miniaturize the film solar cell 1.

[0020] Figure 2 is a top view of the film solar cell 1A. As described above, the film solar cell 1A has a configuration in which multiple solar cells 10 are arranged in parallel on a film substrate 11 and covered with a transparent sealing material 12.

[0021] Figure 3 is a magnified view of a portion of the film solar cell 1A. Multiple solar cells 10 are mounted on the inclined surface 11A of a bellows-shaped film substrate 11 that alternately repeats mountain and valley folds. Between the mountain folds 11C and valley folds 11B of the film substrate 11, the light-receiving surfaces of the multiple solar cells 10 are arranged at a predetermined angle between adjacent solar cells 10. As a result, the light-receiving surfaces of the multiple solar cells 10 are composed of surfaces having two different normal vectors.

[0022] The planar shape of the solar cell 10 is, for example, a strip (rectangle) or a square. The length of the shorter side of the planar shape of the solar cell 10 (width in the case of a strip) is preferably 10 mm or less in order to suppress electrical resistance in the planar direction.

[0023] Figure 4(a) is a cross-sectional view of film solar cell 1A cut along B-B in Figure 2, and Figure 4(b) is a cross-sectional view cut along C-C in Figure 2.

[0024] The solar cell 10 includes a photoelectric conversion unit 100 that generates electrical energy by absorbing light and causing charge separation, an electrode 101 provided on the side of the photoelectric conversion unit 100 facing the film substrate 11, and an electrode 102 provided on the side of the photoelectric conversion unit 100 opposite to the film substrate 11.

[0025] The solar cell 10 can be an organic solar cell, a silicon solar cell, a compound solar cell, or an organic-inorganic hybrid solar cell. The solar cell 10 in this embodiment is a perovskite solar cell. Organic solar cells are generally lighter and more flexible than inorganic solar cells. Perovskite solar cells, in particular, have excellent efficiency in converting to electrical energy.

[0026] The photoelectric conversion unit 100 can take on various known configurations depending on the type of solar cell 10.

[0027] For example, if the solar cell 10 is a perovskite solar cell, the photoelectric conversion unit 100 consists of a perovskite layer where charge separation occurs due to light absorption, and an electron transport layer and a hole transport layer sandwiching it. Electrons generated by charge separation in the perovskite layer flow to the electrode on the electron transport layer side of electrode 101 and electrode 102, and holes generated by charge separation in the perovskite layer flow to the electrode on the hole transport layer side of electrode 101 and electrode 102.

[0028] The film solar cell 1A receives light from the encapsulant 12 side and converts it into electrical energy. Therefore, to avoid obstructing the light entering the photoelectric conversion unit 100 from the encapsulant 12 side, the electrode 102 is made of a transparent material consisting of a metal oxide film such as ITO or FTO. Also, when light is taken in from the film substrate 11 side, to avoid obstructing the light entering the photoelectric conversion unit 100 from the film substrate 11 side, the film substrate 11 is made of a transparent material consisting of a metal oxide film such as ITO or FTO, and the electrode 101 is made of a transparent material such as a transparent material consisting of a metal oxide film such as ITO or FTO. The encapsulant 12 is made of a resin, for example, a resin film such as PET or PEN combined with a silicone-based or epoxy-based adhesive.

[0029] As shown in Figure 4(a), the film substrate 11 is formed in a bellows-like shape with alternating mountain and valley folds, and is configured such that adjacent slopes 11A face each other at a predetermined angle θ1 via valley folds 11B or mountain folds 11C. This predetermined angle θ1 is preferably 80 degrees or more and 170 degrees or less, in order to suppress a decrease in power generation efficiency due to shading even when the direction of light irradiation to the solar cell 10 changes.

[0030] The solar cell 10 is mounted on each inclined surface 11A of the film substrate 11 via electrodes 101. In other words, adjacent solar cells 10 form a concave shape with an angle θ1 on the electrode 101 side and a convex shape with an angle θ1 on the electrode 102 side. The sealing material 12 is formed to cover the electrodes 102 along the solar cell 10 and to eliminate gaps on the valley fold portion 11B or mountain fold portion 11C on the film substrate 11.

[0031] In the solar cell module 1 according to this embodiment, for example, when light shines into the frame 2 from the side opposite to the film substrate 11 of the film solar cell 1A, the light is diffused upon the diffuser plate 3, which is located higher than the top of the folded portion 11C of the film solar cell 1A on the light incidence side. The diffused light is directed toward the light-receiving surfaces of each solar cell 10, which have an uneven shape. However, since the light-receiving surface of the film solar cell 1A is a surface with two different normal vectors, the component of the incident light that exceeds the critical angle is reduced. As a result, the reduction in light energy reaching the photoelectric conversion unit 100 of the solar cell 10 is suppressed. Furthermore, because the light diffused by the diffuser plate 3 passes beyond the folded portion 11C of the film solar cell 1 and travels between the solar cells 10, the occurrence of shadows on the light-receiving surfaces of the solar cells 10 is suppressed, and the light energy reaching the photoelectric conversion unit 100 of the solar cell 10 increases.

[0032] (Regarding variations) Figure 5 is a top view showing a modified example of the solar cell module 1 according to the first embodiment. This modified solar cell module 1 is a film solar cell assembly 20 formed by combining multiple film solar cells 1A. The number, length, and width of the solar cells 10 of each film solar cell 1A, as well as the direction in which the uneven shape formed by the solar cells 10 extends, are determined according to the shape and size of the film solar cell assembly 20, the conditions of the angle of incidence of light in multiple regions of the panel surface, etc.

[0033] According to this modified solar cell module 1, multiple surfaces with different normal vectors can be set on the light-receiving surface of the entire film solar cell assembly 20 on a region-by-region basis, allowing for adjustment of variations in the amount of light received in multiple regions and further increasing power generation efficiency.

[0034] (Effects of the first embodiment) According to the solar cell module 1 of the first embodiment of the present invention described above, the light-receiving surface of the film solar cell 1A has an uneven shape and is composed of surfaces having at least two different normal vectors, so that the component of the incident light that exceeds the critical angle in the incident light incident on the light-receiving surface of the film solar cell 1A is reduced. As a result, the reduction in light energy reaching the photoelectric conversion unit 100 of the solar cell 10 is suppressed. Furthermore, since the diffuser plate 3 is located higher than the top of the light-receiving surface of the solar cell 10 on the light intake side, the light diffused by the diffuser plate 3 passes over the top of the mountain-fold portion 11C of the film solar cell 1A and travels between the solar cells 10, suppressing the occurrence of shadows on the solar cells 10. As a result, the light energy reaching the photoelectric conversion unit 100 of the solar cell 10 increases and the amount of light received per unit area of ​​the light-receiving surface of the solar cell 10 becomes more uniform. As a result, the decrease in power generation efficiency due to the occurrence of shadows can be suppressed. Furthermore, multiple solar cells 10 can be arranged to form mountain folds or valley folds, which reduces the occupied area and allows for miniaturization.

[0035] (Second Embodiment) Figure 6 is a partially enlarged view of the film solar cell 1B in the solar cell module 1 according to the second embodiment. In this embodiment, the film solar cell 1B is formed with a film substrate 11 having a curved surface curved with a predetermined curvature, and the solar cell 10 is curved with the same curvature as the curved surface of the film substrate 11 and mounted on the curved surface of the film substrate 11. As a result, multiple solar cells 10 curved with a predetermined curvature are arranged in the direction of the short side of the solar cell 10, and the solar cells 10 form an uneven shape with each other. Here, the predetermined curvature is set to such an extent that cracks or the like do not occur in the solar cell 10 due to bending stress. In this embodiment, the solar cell 10 is mounted on a convex curved surface, but it may also be mounted on a concave curved surface.

[0036] (Effects of the second embodiment) According to the solar cell module 1 of the second embodiment of the present invention described above, the solar cells 10 of the film solar cell 1B form an uneven shape with respect to each other, and the light-receiving surface of the solar cell 10 is composed of a surface having at least two different normal vectors. Therefore, even if the angle of incidence of light deviates from the direction normal to the panel surface, a decrease in power generation efficiency can be suppressed. Furthermore, in the solar cell module 1 of the second embodiment, because there is a limit to the curvature of the solar cell 10, the top of the light-receiving surface is lower than the top of the mountain-fold portion 11C of the solar cell module 1 of the first embodiment. As a result, the configuration makes it difficult for shadows to be cast on the solar cell 10, and the light diffused by the diffuser plate 3 can pass over the top of the light-receiving surface of the film solar cell 1B and easily travel between the solar cells 10.

[0037] (Third embodiment) Figure 7 is a partially enlarged view of the film solar cell 1C in the solar cell module 1 according to the third embodiment. In this embodiment, the film solar cell 1C is formed with a film substrate 11 having a curved surface curved with a predetermined curvature, and solar cells 10, which are curved with the same curvature as the curved surface of the film substrate 11, are mounted on the curved surface of the film substrate 11 in a state where they are divided into two parts. As a result, multiple solar cells 10 curved with a predetermined curvature are arranged in the direction of the short side of the solar cell 10, and the solar cells 10 form an uneven shape with each other. In this embodiment, the solar cells 10 are mounted on a curved surface that is curved in a convex shape, but they may also be mounted on a curved surface that is curved in a concave shape.

[0038] The solar cell module 1 according to the third embodiment of the present invention described above can also achieve the same effects as the solar cell module 1 according to the second embodiment of the present invention.

[0039] Although embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the invention. Furthermore, the components of the above embodiments can be arbitrarily combined without departing from the spirit of the invention.

[0040] Furthermore, the above embodiments do not limit the invention as defined in the claims. It should also be noted that not all combinations of features described in the embodiments are necessarily essential for solving the problem of the invention. [Explanation of Symbols]

[0041] 1...Solar cell module, 1A, 1B, 1C...Film solar cell, 2...Frame, 3...Diffuser plate, 10...Solar cell, 11...Film substrate, 11A...Slope, 11B...Valley fold section, 11C...Mountain fold section, 12...Sealing material, 14...Electrode, 20...Film solar cell assembly, 100...Photoelectric conversion section, 101, 102...Electrode

Claims

1. Film substrate and A solar cell, which is arranged on the aforementioned film substrate and converts light energy into electrical energy, The solar cell comprises a diffuser plate that diffuses the light on the light incidence side, The light-receiving surface of the solar cell includes a surface having at least two different normal vectors. Solar cell module.

2. The aforementioned film substrate is formed in a bellows-like shape with alternating mountain and valley folds, Multiple solar cells are located on the slope between the mountain folds and valley folds of the film substrate. Mounted on top, The solar cell module according to claim 1.

3. The aforementioned film substrate is formed having a curved surface that is curved with a predetermined curvature, The solar cell is curved with the same curvature as the curved surface and mounted on the curved surface of the film substrate. The solar cell module according to claim 1.

4. Multiple solar cells are mounted in sections on the curved surface of the film substrate. The solar cell module according to claim 3.

5. The diffuser plate is provided at a position higher than the top of the light-receiving surface of the solar cell on the light-incident side. A solar cell module according to any one of claims 1 to 4.

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