Photoelectric conversion device

Abstract

To solve the problem of conventional photoelectric conversion devices that stress-induced degradation occurs in a region of a solar cell near a winding shaft and power generation performance lowers.SOLUTION: Provided is a photoelectric conversion device 1 comprising a flexible sheet 2, a flexible photoelectric conversion cell disposed to the sheet 2, and a core member 3 for winding of the sheet 2. With the direction from one end to the other end of the sheet 2 assumed to be a development direction, a plurality of photoelectric conversion cells C1-C7 are juxtaposed to the sheet 2 in the development direction, and a boundary B of adjacent photoelectric conversion cells is located in parallel to the core member 3, with a length L1 in the development direction of a photoelectric conversion cell C1 adjacent to the core member 3 among the plurality of photoelectric conversion cells C1-C7 being relatively smaller than a length L in the development direction of the other photoelectric conversion cells. Thus, the degradation of photoelectric conversion cell C1 adjacent to the core member 3 is suppressed and good power generation performance is maintained.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an improvement of a photoelectric conversion device in which a photoelectric conversion cell is arranged on a rollable sheet.

Background Art

[0002] Conventionally, a photoelectric conversion device as described above is, for example, one described in Patent Document 1 under the name of a roll curtain device. Patent Document 1 has a structure in which a roll screen is provided in a box fixed to the upper part of a window of a building so as to be rollable, and a film-type solar cell is attached to the window-side surface of the roll screen. This roll curtain device generates electricity by pulling out and deploying the roll screen in the box with a film-type solar cell.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above-described conventional photoelectric conversion device, when the roll screen is repeatedly wound and deployed, particularly, a bending and tensile load with a small radius of curvature is repeatedly applied to the vicinity of the winding shaft in the solar cell, and the solar cell deteriorates due to the stress caused thereby, and there is a problem that the power generation performance may decrease.

[0005] The present invention has been made in view of the above-described conventional situation, and an object of the present invention is to provide a photoelectric conversion device that can suppress deterioration of a photoelectric conversion cell and maintain good power generation performance in a sheet-like photoelectric conversion device in which winding and deployment are repeatedly performed.

Means for Solving the Problems

[0006] The photoelectric conversion device according to the present invention is a photoelectric conversion device including a flexible sheet, a flexible photoelectric conversion cell disposed on the sheet, and a winding core member connected to one end of the sheet. In this photoelectric conversion device, the direction from one end of the sheet to the other end is defined as the unfolding direction, and a plurality of photoelectric conversion cells are arranged side by side in the unfolding direction on the sheet, and the boundaries between adjacent photoelectric conversion cells are arranged parallel to the core member. And, the photoelectric conversion device is characterized in that the length in the unfolding direction of the photoelectric conversion cell adjacent to the core member among the plurality of photoelectric conversion cells is relatively smaller than the length in the unfolding direction of the other photoelectric conversion cells.

Effects of the Invention

[0007] By adopting the above configuration in the sheet-shaped photoelectric conversion device in which winding and unfolding are repeatedly performed, the photoelectric conversion device according to the present invention can particularly suppress the deterioration of the photoelectric conversion cells in the vicinity of the core member serving as the winding center and maintain good power generation performance.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0009] <First Embodiment> The photoelectric conversion device 1 shown in Fig. 1 includes a flexible sheet 2, flexible photoelectric conversion cells C1 to C7 disposed on the sheet 2, and a winding core member 3 connected to one end of the sheet 2.

[0010] In the above photoelectric conversion device 1, taking the direction from one end to the other end of the sheet 2 (left direction in Fig. 1) as the unfolding direction and the reverse direction as the winding direction, a plurality (seven in the illustrated example) of photoelectric conversion cells C1 to C7 are arranged side by side in the unfolding direction on the sheet 2, and the boundary B between adjacent photoelectric conversion cells is arranged parallel to the core member 3.

[0011] And, in the above photoelectric conversion device 1, the length L1 in the unfolding direction of the photoelectric conversion cell C1 adjacent to the core member 3 among the plurality of photoelectric conversion cells C1 to C7 is relatively smaller than the length L in the unfolding direction of the other photoelectric conversion cells 2 to C7.

[0012] The sheet 2 is made of, for example, resin, and has a rectangular shape with the unfolding direction as the long side in the illustrated example. Each of the photoelectric conversion cells C1 to C7 may be flexible, and in a more preferred embodiment, it is an organic solar cell and a perovskite solar cell.

[0013] Also, the length L1 in the unfolding direction of the photoelectric conversion cell C1 adjacent to the core member 3 can be selected according to the properties of the photoelectric conversion cell C, the diameter of the core member 3, etc., and can be appropriately selected, for example, to be equal to or less than the length of the entire circumference of the core member 3, equal to or less than half the circumference of the core member 3, equal to or less than the length of the diameter of the core member 3, and so on.

[0014] Each of the photoelectric conversion cells C1 to C7 has a rectangular shape with the same width in the direction perpendicular to the unfolding direction (width in the up and down direction in Fig. 1), and they are arranged including those with different or the same length L in the unfolding direction. Thereby, the boundary B between adjacent photoelectric conversion cells forms a straight line parallel to the core member 3.

[0015] The above-described photoelectric conversion device 1 is used, for example, as a sunshade attached to the upper part of the windshield G of the vehicle V as shown in FIG. 2. In this case, the photoelectric conversion device 1 is housed in a case K attached to the upper part of the windshield G (the position of the sun visor). The photoelectric conversion cells C1 to C7 are arranged on the surface of the sheet 2 on the windshield G side.

[0016] In the case K, a well-known winding device including a spring that biases the core member 3 in a certain rotation direction and a latch that can be engaged with and disengaged from the core member 3 is arranged. Thereby, when the photoelectric conversion device 1 pulls down the sheet 2 and unfolds it to an arbitrary position, the unfolded state is maintained by the engagement of the latch. When winding up, by slightly pulling down the sheet 2, the restraint by the latch is released, and the core member 3 is rotated by the spring to automatically wind up the sheet 2. In addition, at the other end (lower end) of the sheet 2, a stopper that abuts against the open portion of the case K, a handle for operation, a suction cup for fixing to the windshield G, etc. can be provided.

[0017] When the above-described photoelectric conversion device 1 is in a state where the sheet 2 is unfolded, it functions as a light-shielding body and generates electricity by the photoelectric conversion cells C1 to C7 arranged on the sheet 2. When not in use, the sheet 2 is wound around the core member 3. That is, the photoelectric conversion device 1 repeats winding and unfolding. In particular, a bending and tensile load with a small radius of curvature is repeatedly applied to the vicinity of the winding axis of the sheet 2.

[0018] On the other hand, the above-described photoelectric conversion device 1 has a structure in which the length L1 in the unfolding direction of the photoelectric conversion cell C1 adjacent to the core member 3 is made relatively smaller than the length L in the unfolding direction of the other photoelectric conversion cells 2 to C7. Therefore, the photoelectric conversion cell C1 adjacent to the core member 3 is prevented from being excessively bent to relieve stress. In this way, the above-described photoelectric conversion device 1 can suppress deterioration due to stress of the photoelectric conversion cell C1 adjacent to the core member 3 and maintain good power generation performance in a sheet-shaped photoelectric conversion device in which winding and unfolding are repeatedly performed.

[0019] In addition, since the photoelectric conversion cells C1 to C7 of the above photoelectric conversion device 1 are organic solar cells and perovskite solar cells, it is possible to improve the durability and flexibility of the photoelectric conversion cells C1 to C7, and further enhance the deterioration prevention function of the photoelectric conversion cells C1 to C7.

[0020] Figs. 3 to 6 are diagrams for explaining the second to fourth embodiments of the photoelectric conversion device according to the present invention. In the following embodiments, the same reference numerals are given to the same constituent parts as those in the first embodiment, and detailed descriptions thereof are omitted. Note that each drawing schematically shows each configuration for convenience, and the exact position, size, etc. of each configuration are not limited to those shown in the drawings.

[0021] <Second Embodiment> In the photoelectric conversion device 1 shown in Fig. 3, a plurality (five in the illustrated example) of photoelectric conversion cells C1 to C5 have different lengths L1 to L5 in the unfolding direction, and in the unfolding direction, the lengths L1 to L5 are arranged in ascending order from the photoelectric conversion cell C1 closest to the core member 3.

[0022] That is, the boundaries B between the photoelectric conversion cells C1 to C5 are parallel to the core member 3, and the length L1 of the unfolding method of the photoelectric conversion cell C1 adjacent to the core member 3 is the smallest, and in the unfolding direction, the respective lengths L2 to L5 increase sequentially. Therefore, the photoelectric conversion cells C1 to C5 have a structure in which the area increases sequentially in the unfolding direction, and are connected in series, for example.

[0023] Similar to the first embodiment, the photoelectric conversion device 1 having the above configuration can suppress the deterioration of the photoelectric conversion cell C1 in the vicinity of the core member 3 that becomes the winding center, maintain good power generation performance, secure a wide effective power generation area, and increase the overall power generation amount.

[0024] <Third Embodiment> The photoelectric conversion device 1 shown in Fig. 4 is composed of a plurality of (six in the illustrated example) photoelectric conversion cells C1 to C6, and all of the photoelectric conversion cells C1 to C6 or other photoelectric conversion cells C2 to C6 other than the photoelectric conversion cell C1 adjacent to the core member 3 are composed of a plurality of divided cells SC arranged in parallel with the core member 3.

[0025] Note that in the photoelectric conversion device 1 of the illustrated example, the second and subsequent photoelectric conversion cells C2 to C6 from the core member 3 are composed of a plurality of divided cells SC, but the photoelectric conversion cell C1 adjacent to the core member 3 may also be composed of a plurality of divided cells SC.

[0026] And the photoelectric conversion cells C2 to C6 composed of the divided cells SC have the number of divided cells SC increasing sequentially in the unfolding direction, the areas of the divided cells SC being equal to each other, and being connected in series with each other.

[0027] That is, the second photoelectric conversion cell C2 from the core member 3 has two divided cells SC having the same area as the photoelectric conversion cell C1 adjacent to the core member 3. Also, the third photoelectric conversion cell C3 has three divided cells SC having the same area as the divided cells SC in the second photoelectric conversion cell C2. Hereinafter, in the unfolding direction, the number of divided cells SC having the same area increases sequentially for each photoelectric conversion cell.

[0028] Thereby, the above-mentioned photoelectric conversion device 1 has a structure in which the total effective area of each of the photoelectric conversion cells C1 to C6 increases sequentially in the unfolding direction, similar to the second embodiment (see Fig. 3).

[0029] Incidentally, in the photoelectric conversion device 1, as shown in Fig. 5(A), when one cell CA and the other cell CB with different areas are connected in series, as shown in Figs. 5(B) and (C), the voltage values at the respective optimum operating points (when the maximum output is obtained) are different, so the output of the other cell CB with a large area may decrease. In this case, as shown in Fig. 5(D), when the other cell CB is composed of two divided cells SC having the same area as one cell CA, as shown in Fig. 5(E), it becomes a structure in which three cells Ca, Cb, and Cc of the same area, that is, three cells Ca, Cb, and Cc with the same optimum current-voltage, are connected in series, and the total output shown in Fig. 5(F) with the output tripled can be obtained.

[0030] Therefore, by adopting the above-described configuration shown in Fig. 4, the photoelectric conversion device 1 of this embodiment can suppress the deterioration of the photoelectric conversion cell C1 in the vicinity of the core member 3 that becomes the winding center, maintain good power generation performance, and prevent the output reduction caused by the difference in the optimum operating point, as in the first embodiment.

[0031] In addition, since the power generation performance of the above-described photoelectric conversion device 1 is improved, for example, as shown in Fig. 2, when applied to the sunshade of the vehicle V, it can be used not only as a power source for auxiliary equipment but also as a part of the power source for the drive system.

[0032] <Fourth Embodiment> The photoelectric conversion device 1 shown in Fig. 6 has a basic configuration in which the boundary B between the photoelectric conversion cells is parallel to the core member 3 and the length L1 in the unfolding direction of the photoelectric conversion cell C1 adjacent to the core member 3 is relatively small, and a plurality (seven in the illustrated example) of photoelectric conversion cells C1 to C7 are partitioned into a plurality (three in the illustrated example) of modules M1 to M3 each composed of a plurality of the photoelectric conversion cells connected in series or in parallel.

[0033] And each of the modules M1 to M3 in the above-described photoelectric conversion device 1 has the same total area of the photoelectric conversion cells and is connected in series with each other. More specifically, the illustrated photoelectric conversion device 1 constitutes the first module M1 by connecting four photoelectric conversion cells C1 to C4 from the third to the fourth in the deployment direction in parallel. Further, the photoelectric conversion device 1 constitutes the second module M2 by connecting two photoelectric conversion cells C5 and C6 of the fifth and sixth in parallel, and constitutes the third module M3 with one photoelectric conversion cell C7 of the seventh, and connects the modules M1 to M3 in series.

[0034] The photoelectric conversion device 1 having the above configuration can obtain the same effects as those of the first embodiment, and can prevent the output reduction caused by the difference in the optimum operating point and can further improve the power generation performance, similar to the third embodiment.

[0035] The configuration of the photoelectric conversion device according to the present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the gist of the present invention, and is applicable not only to vehicle sunshades but also to roll curtains for building windows and the like.

Explanation of Reference Numerals

[0036] 1 Photoelectric conversion device 2 Sheet 3 Core member B Boundary between cells C1 to C7 Photoelectric conversion cells M1 to M3 Modules SB Split cell

Claims

1. A photoelectric conversion device comprising a flexible sheet, a flexible photoelectric conversion cell disposed on the sheet, and a winding core member connected to one end of the sheet, wherein the direction from one end to the other end of the sheet is defined as the unfolding direction, a plurality of the photoelectric conversion cells are arranged side by side in the unfolding direction on the sheet, and the boundaries between adjacent photoelectric conversion cells are arranged parallel to the core member, and the length of the photoelectric conversion cell adjacent to the core member among the plurality of photoelectric conversion cells in the unfolding direction is relatively smaller than the length of the other photoelectric conversion cells in the unfolding direction.

2. The photoelectric conversion device according to claim 1, wherein the lengths of the plurality of photoelectric conversion cells in the unfolding direction are different from each other, and in the unfolding direction, they are arranged in ascending order of length starting from the one closer to the core member.

3. All of the photoelectric conversion cells, or the photoelectric conversion cells other than the photoelectric conversion cells adjacent to the core member, are composed of a plurality of divided cells arranged parallel to the core member, and each of the photoelectric conversion cells is characterized in that the number of the divided cells increases sequentially in the unfolding direction, the areas of the divided cells are equal to each other, and they are connected in series with each other.

4. The plurality of photoelectric conversion cells are partitioned into a plurality of modules each composed of a plurality of the photoelectric conversion cells connected in series or in parallel, and each of the modules is characterized in that the total areas of the photoelectric conversion cells are equal to each other and they are connected in series with each other.

5. The photoelectric conversion device according to any one of claims 1 to 4, wherein the photoelectric conversion cell is an organic solar cell and a perovskite solar cell.

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