Method for manufacturing photoelectric conversion cells
The method addresses the issues of damage and deformation in roll-to-roll manufacturing by parallel lamination and cutting without winding, achieving space and labor savings with high-quality photoelectric conversion cells.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- TOYODA GOSEI CO LTD
- Filing Date
- 2024-11-26
- Publication Date
- 2026-06-05
AI Technical Summary
The roll-to-roll method for manufacturing photoelectric conversion cells faces challenges such as damage and deformation due to friction and pressure during winding, requiring large equipment and separate processes for layer formation and cutting, leading to increased labor costs.
A method involving a lamination step on a flexible strip-shaped substrate followed by a cutting step without winding, with parallel execution of both processes, using a buffer section to stabilize the laminate before cutting, and applying tension through rollers to maintain stability during lamination.
This method reduces equipment space and labor requirements while preventing damage to the layers, enabling high-quality cell production with improved efficiency and reduced manufacturing time.
Smart Images
Figure 2026092484000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a method for manufacturing a flexible photoelectric conversion cell.
Background Art
[0002] Conventionally, in the method for manufacturing a perovskite solar cell, for example, as described in Patent Document 1, a roll-to-roll method using a pair of rolls has been widely used. The roll-to-roll method is a method in which a long workpiece is supplied from one roll for processing, and the processed workpiece is wound around the other roll.
[0003] Patent Document 1 describes a method for manufacturing a solar cell in which a flexible belt-like substrate is drawn out from one roll, and a lower electrode, a photoelectric conversion layer containing a perovskite compound, an upper electrode, and a planarization layer made of a thermosetting resin are sequentially laminated on the substrate by a continuous film-forming method, the obtained long laminate is wound around the other roll, and then the long laminate is cut at a plurality of locations to obtain individual solar cells.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0005] The roll-to-roll method allows for the continuous formation of various layers, such as the photoelectric conversion layer, over a large area, resulting in excellent mass production efficiency and low-cost solar cell manufacturing. However, if the formation of each layer is insufficient during winding, damage and deformation are likely to occur due to friction and pressure during winding. Therefore, before winding the long laminate with each layer formed on the substrate, it is necessary to perform a hardening treatment such as heating on the long laminate as it moves towards the winding roll, which leads to the challenge of requiring large manufacturing equipment. In addition, the process of forming each layer on the substrate and the process of cutting the long laminate at multiple points are separate processes, and these processes cannot be performed in parallel, resulting in increased labor costs.
[0006] The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a method for manufacturing photoelectric conversion cells that enables space saving and labor saving in the manufacturing equipment. [Means for solving the problem]
[0007] One aspect of the present invention provides the following method for manufacturing a photoelectric conversion cell in order to achieve the above objective.
[0008] [1] A method for manufacturing a photoelectric conversion cell, comprising: a lamination step of sequentially forming a lower electrode, a photoelectric conversion layer, an upper electrode, and an insulating layer on a flexible strip-shaped substrate to form a laminate; and a cutting step of cutting the laminate into predetermined lengths, wherein the lamination step is performed while unwinding the substrate wound on a rotating core at a constant speed, and the cutting step is performed in parallel with the lamination step without winding the laminate after the lamination step. [2] The method for manufacturing a photoelectric conversion cell according to [1], further comprising a stocking step of placing laminate pieces cut to a predetermined length onto a plate-shaped support member, and arranging a plurality of the support members on which the laminate pieces are placed in the plate thickness direction with spacing between them. [3] The method for manufacturing a photoelectric conversion cell according to [1], wherein in the cutting step, the movement of the laminate is stopped before the cutting position and the laminate is cut, and a buffer portion is provided between the lamination forming apparatus that performs the lamination step and the cutting apparatus that performs the cutting step to support the laminate in a flexed state. [4] A method for manufacturing a photoelectric conversion cell according to [3], wherein a roller for applying tension to the substrate in the lamination process is placed between the buffer portion and the lamination forming apparatus, and in the lamination process, the lower electrode, the photoelectric conversion layer, the upper electrode, and the insulating layer are sequentially formed on one surface of the substrate while the substrate, which has been subjected to tension by the roller, is moved. [5] A method for producing a photoelectric conversion cell according to any one of the above [1] to [4], wherein the photoelectric conversion layer contains a perovskite compound. [Effects of the Invention]
[0009] The method for manufacturing photoelectric conversion cells according to the present invention makes it possible to reduce the space and labor required for manufacturing equipment. [Brief explanation of the drawing]
[0010] [Figure 1] Figure 1(a) is a plan view of a photoelectric conversion cell according to an embodiment of the present invention. Figure 1(b) is a cross-sectional view along line AA in Figure 1(a). [Figure 2] Figures 2(a) and 2(b) are schematic diagrams of a production system for manufacturing photoelectric conversion cells according to an embodiment of the present invention. [Figure 3] Figure 3 is a diagram showing an example configuration of a cell rack that houses multiple photoelectric conversion cells. [Modes for carrying out the invention]
[0011] Figure 1(a) is a plan view of a photoelectric conversion cell 1 according to an embodiment of the present invention. Figure 1(b) is a cross-sectional view of the photoelectric conversion cell 1 along line AA in Figure 1(a). In Figure 1(b), the dimensions in the thickness direction of the photoelectric conversion cell 1 are exaggerated for clarity.
[0012] The photoelectric conversion cell 1 comprises a flexible film-like substrate 11, a lower electrode 12, a photoelectric conversion layer 13, an upper electrode 14, and an insulating layer 15 formed on one surface 11a of the substrate 11. The substrate 11 is made of a resin such as acrylic, PET (polyethylene terephthalate), PEN (polyethylene naphthalate), polycarbonate, polyethersulfone, fluorine film, or triacetate, and is light-transmitting. The insulating layer 15 is made of a light-transmitting resin, similar to the substrate 11, and seals the lower electrode 12, the photoelectric conversion layer 13, and the upper electrode 14.
[0013] The photoelectric conversion layer 13 consists of a perovskite layer in which charge separation occurs due to light absorption, and an electron transport layer and a hole transport layer sandwiching the perovskite layer. The perovskite layer contains a perovskite compound represented by the general formula RM-X3. In this general formula, R is an organic molecule, M is a metal atom, and X is a halogen atom or a chalcogen atom.
[0014] Electrons generated by charge separation in the perovskite layer flow to the electron transport layer electrode of the lower electrode 12 and upper electrode 14, while holes generated by charge separation in the perovskite layer flow to the hole transport layer electrode of the lower electrode 12 and upper electrode 14. Transparent electrodes made of metal oxides such as ITO (indium tin oxide) or FTO (fluorine-doped tin oxide) are used for the lower electrode 12 and upper electrode 14.
[0015] Multiple photoelectric conversion cells 1 are combined to form a photoelectric conversion module, which is used, for example, as a solar cell that generates electricity from sunlight. In the photoelectric conversion module, the lower electrodes 12 and upper electrodes 14 of multiple photoelectric conversion cells 1 are electrically connected in series.
[0016] Next, a method for manufacturing the photoelectric conversion cell 1 will be described. The method for manufacturing the photoelectric conversion cell 1 in this embodiment is different from the roll-to-roll method that is widely used at present. Instead of using the roll-to-roll method, a long substrate 11 wound in a roll is pulled out and flattened, and then a lower electrode 12, a photoelectric conversion layer 13, an upper electrode 14, and an insulating layer 15 are sequentially formed on the flattened substrate 11. After that, without winding up again, the substrate 11 is cut to a predetermined length together with the lower electrode 12, the photoelectric conversion layer 13, the upper electrode 14, and the insulating layer 15 while maintaining the flat body. In this embodiment, this method for manufacturing the photoelectric conversion cell 1 is called the roll-to-batch method.
[0017] The method for manufacturing the photoelectric conversion cell 1 by the roll-to-batch method according to this embodiment includes a lamination step of sequentially forming a lower electrode 12, a photoelectric conversion layer 13, an upper electrode 14, and an insulating layer 15 on a flexible belt-shaped substrate 11 to form a laminate, and a cutting step of cutting the laminate at a predetermined length. The lamination step is performed while feeding out the substrate 11 wound around a rotating core material at a constant speed. In the cutting step, the laminate is cut without winding up the laminate after the lamination step. Also, the cutting step is performed in parallel with the lamination step.
[0018] Moreover, the manufacturing method of this embodiment further includes a stock step of placing the laminate pieces obtained by cutting the laminate at a predetermined length on a plate-shaped support member, and arranging a plurality of support members on which the laminate pieces are placed side by side in the plate thickness direction with a gap between them. Next, a configuration example of a production system for implementing the manufacturing method of this embodiment will be described with reference to FIG. 2.
[0019] FIGS. 2(a) and (b) are schematic configuration diagrams of a production system 2 for manufacturing the photoelectric conversion cell 1 by the roll-to-batch method. FIG. 2(a) shows the state immediately before cutting in the cutting step, and FIG. 2(b) shows the state after cutting. In FIGS. 2(a) and (b), for clarity of the illustrated content, the thickness of the substrate 11 and the thickness of the laminate 10 formed with the lower electrode 12, the photoelectric conversion layer 13, the upper electrode 14, and the insulating layer 15 on the substrate 11 are exaggeratedly shown.
[0020] This production system 2 includes a core material 21 around which a long strip-shaped base material 11 is wound in a roll, a plurality of guide rollers 221 to 223 for guiding the strip-shaped base material 11 fed out by the rotation of the core material 21, a lamination forming device 22 for performing a lamination process, a cutting device 23 for performing a cutting process, a belt conveyor 24 as a conveying device for conveying the laminate pieces 100 cut to a predetermined length by the cutting device 23, and a cell rack 25 for accommodating a plurality of laminate pieces 100.
[0021] The core material 21 is cylindrical and rotates about a central axis C. The plurality of guide rollers 221 to 223 guide the strip-shaped base material 11 fed out by the rotation of the core material 21 to the lamination forming device 22. The strip-shaped base material 11 is introduced into the lamination forming device 22 in a flat state by the tension applied in its longitudinal direction.
[0022] The lamination forming device 22 sequentially forms a lower electrode 12, a photoelectric conversion layer 13, an upper electrode 14, and an insulating layer 15 on one surface 11a (see FIG. 1) of the base material 11. The lower electrode 12 and the upper electrode 14 are continuously formed, for example, by printing and coating, vapor deposition, sputtering, or ion plating. The photoelectric conversion layer 13 is continuously formed, for example, by a vacuum evaporation method, a sputtering method, a gas phase reaction method (CVD), an electrochemical deposition method, or a printing method. The insulating layer 15 is formed, for example, by adhering a resin film made of PET or PEN.
[0023] The lamination forming device 22 continuously forms the lower electrode 12, the photoelectric conversion layer 13, the upper electrode 14, and the insulating layer 15 on the strip-shaped base material 11 moving in the longitudinal direction at a constant speed, and constitutes a long laminate 10. The laminate 10 is led out from the lamination forming device 22 at a constant speed. This speed is, for example, 3 to 10 m / min.
[0024] The cutting device 23 has a cutting tool 231 and a moving mechanism 232 for moving the cutting tool 231, and the cutting tool 231 cuts the laminate 10 on the belt conveyor 24. The laminate pieces 100 cut from the laminate 10 to a predetermined length are transported by the belt conveyor 24 and placed on a plate-shaped support member 3, and are stored in the cell rack 25 together with the support member 3. The support member 3 is made of, for example, a glass plate. Alternatively, the support member 3 may be placed on the belt conveyor 24, and the laminate 10 may be cut on this support member 3.
[0025] The laminated pieces 100 are stored in the cell rack 25 as they are, but if the laminated pieces 100 are thin and have a lot of flexibility, it is desirable to store them in the cell rack 25 while they are fixed to the support member 3. Examples of methods for fixing the laminated pieces 100 to the support member 3 include fixing with tape or fixing with a removable adhesive that can be peeled off from the support member 3 without damaging the base material 11.
[0026] In the cutting process, the movement of the laminate 10 is stopped just before it reaches the cutting position of the laminate 10 by the cutting tool 231, and the laminate 10 is cut. This is because it is difficult to cut the laminate 10 accurately and stably while it is moving. For this reason, in this embodiment, a buffer section 20 is provided between the lamination forming device 22 and the cutting device 23 to support the long laminate 10 in a flexed state.
[0027] The buffer section 20 is provided between the roller 26 on the upstream side (laminated assembly device 22 side) and the roller 27 on the downstream side (cutting device 23 side). The upstream roller 26 rotates at a constant speed, while the downstream roller 27 rotates intermittently. The upstream roller 26 and the downstream roller 27 rotate around both ends of the base material 11 (both ends in the left and right directions in Figures 1(a) and (b)) where the lower electrode 12, photoelectric conversion layer 13, upper electrode 14, and insulating layer 15 are not formed, so as not to crush the lower electrode 12, photoelectric conversion layer 13, upper electrode 14, and insulating layer 15 formed by the laminated assembly device 22. These ends of the base material 11 correspond to both ends in the width direction perpendicular to the direction of movement of the laminate 10.
[0028] The upstream roller 26 rotates the laminate 10 so as to pull it downstream in its longitudinal direction, so that tension is maintained in the lamination apparatus 22 even after the laminate 10 is cut. In other words, the upstream roller 26 applies longitudinal tension to the base material 11 during the lamination process. During the lamination process, the base material 11, which has been tensioned by the upstream roller 26, is moved while the lower electrode 12, photoelectric conversion layer 13, upper electrode 14, and insulating layer 15 are sequentially formed on one surface 11a of the base material 11.
[0029] The downstream roller 27 stops before and after the cutting device 23 cuts the laminate 10, and rotates at a higher speed than the upstream roller 26 after the cutting device 23 has cut the laminate 10. This rotation of the downstream roller 27 pushes a portion of the laminate 10, which was supported in a flexed state between the upstream roller 26 and the downstream roller 27, onto the belt conveyor 24. As a result, the length of the laminate 10 between the upstream roller 26 and the downstream roller 27 is temporarily shortened. In addition, because the downstream roller 27 stops before and after cutting, the length of the laminate 10 that has been fed out from the lamination device 22 during that time is supported in a flexed state between the upstream roller 26 and the downstream roller 27.
[0030] The laminated pieces 100 cut out by the cutting device 23 are attached to the support 3, or, without using the support 3, are placed directly into the cell rack 25 as photoelectric conversion cells 1 and sent to the next process. In the next process, the lower electrodes 12 and upper electrodes 14 of the multiple photoelectric conversion cells 1 are connected by wiring and attached to a frame.
[0031] Figure 3 is a diagram showing the cell rack 25 and the multiple photoelectric conversion cells 1 housed in the cell rack 25. Note that the thickness of the photoelectric conversion cells 1 is exaggerated in Figure 3.
[0032] Multiple photoelectric conversion cells 1 are each placed on a support member 3 in a flat state and arranged vertically in a cell rack 25. The cell rack 25 has a pair of side plates 251, a top plate 252 and a bottom plate 253 provided above and below the pair of side plates 251, and a plurality of support pieces 254 that support the support member 3. The operation of housing the photoelectric conversion cells 1 together with the support member 3 in the cell rack 25 is performed, for example, by a robot, but may also be performed manually by an operator.
[0033] (Effects of the embodiment) According to the manufacturing method for photoelectric conversion cells of the above embodiment, the laminate 10 is cut after the lamination process without being wound up to obtain a laminate piece 100 which is a photoelectric conversion cell 1. Therefore, a high-quality photoelectric conversion cell 1 can be manufactured without damaging the lower electrode 12, photoelectric conversion layer 13, upper electrode 14, and insulating layer 15 formed in the lamination forming apparatus 22. In other words, in the conventional roll-to-roll method, the laminate, on which the lower electrode, photoelectric conversion layer, upper electrode, and insulating layer are formed on the substrate is wound onto a roll. As a result, the lower electrode, photoelectric conversion layer, upper electrode, or insulating layer is prone to damage or deformation due to friction and pressure during winding. However, according to the manufacturing method of this embodiment, the occurrence of such damage or deformation can be suppressed.
[0034] Furthermore, according to the method for manufacturing a photoelectric conversion cell in the above embodiment, the lamination process and the cutting process are performed simultaneously and in parallel, which shortens the manufacturing time of the photoelectric conversion cell 1. In addition, since the long laminated body with each layer formed on the base material 11 is not wound onto a roll, it is possible to save space and labor in the manufacturing equipment at the factory.
[0035] Furthermore, according to the method for manufacturing a photoelectric conversion cell in the above embodiment, the laminated piece 100 is placed on the support member 3 while maintaining a flat plate shape and then housed in the cell rack 25. This allows the photoelectric conversion cell 1 to be sent to the next process while minimizing damage to the lower electrode 12, photoelectric conversion layer 13, upper electrode 14, and insulating layer 15 due to bending.
[0036] Furthermore, according to the method for manufacturing a photoelectric conversion cell in the above embodiment, a buffer section 20 is provided between the lamination apparatus 22 and the cutting apparatus 23, and the movement of the laminate 10 is stopped before the cutting position by the cutting apparatus 23, thereby cutting the laminate 10. This makes it possible to cut the laminate 10 accurately and stably while moving the base material 11 at a constant speed during the lamination process.
[0037] Furthermore, according to the method for manufacturing a photoelectric conversion cell according to the above embodiment, tension is applied to the base material 11 during the lamination process by the roller 26 placed between the buffer section 20 and the lamination apparatus 22. Therefore, even if the laminate 10 is cut, tension can continue to be applied to the base material 11 during the lamination process, and the lower electrode 12, photoelectric conversion layer 13, upper electrode 14, and insulating layer 15 can be stably formed on the base material 11.
[0038] Furthermore, in this embodiment, since the photoelectric conversion layer 13 contains a perovskite compound, a flexible photoelectric conversion cell 1 with high photoelectric conversion efficiency can be obtained.
[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 added or omitted without departing from the spirit of the invention. Moreover, the above embodiments do not limit the invention as claimed. 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]
[0040] 1. Photoelectric conversion cell 3. Support member 10 Laminate 11 Base material 12 Lower electrode 13 Photoelectric conversion layer 14 Upper electrode 15. Insulating layer 21 Core material 20 Buffer section 22 Lamination Forming Apparatus 23 Cutting device 27 Laura 100 laminated pieces
Claims
1. A lamination process in which a lower electrode, a photoelectric conversion layer, an upper electrode, and an insulating layer are sequentially formed on a flexible strip-shaped substrate to constitute a laminate, The process includes a cutting step of cutting the laminate into predetermined lengths, The lamination process is carried out while the substrate wound around a rotating core is unwound at a constant speed. The cutting step is performed in parallel with the lamination step, without winding the laminate after the lamination step. A method for manufacturing a photoelectric conversion cell.
2. The laminate further comprises a stocking step in which laminate pieces cut to a predetermined length are placed on a plate-shaped support member, and the plurality of support members on which the laminate pieces are placed are arranged in the thickness direction with spacing between them. A method for manufacturing a photoelectric conversion cell according to claim 1.
3. In the cutting process, the movement of the laminate is stopped just before the cutting position and the laminate is cut. A buffer section is provided between the lamination forming apparatus that performs the lamination process and the cutting apparatus that performs the cutting process, to support the laminated body in a flexed state. A method for manufacturing a photoelectric conversion cell according to claim 1.
4. A roller is placed between the buffer section and the lamination apparatus to apply tension to the substrate during the lamination process. In the lamination process, the lower electrode, the photoelectric conversion layer, the upper electrode, and the insulating layer are sequentially formed on one surface of the substrate while the substrate, under tension applied by the roller, is moved. A method for manufacturing a photoelectric conversion cell according to claim 3.
5. The photoelectric conversion layer contains a perovskite compound. A method for manufacturing a photoelectric conversion cell according to any one of claims 1 to 4.