Battery cell assembly, method for manufacturing battery cell assembly, solar cell unit, and method for manufacturing solar cell unit

Abstract

The present invention relates to an assembly (100) of solar cell units, which has a plurality of small compartments (10) that are each divided into a plurality of solar cell units and have a straight side when viewed from above. The plurality of small compartments (10) are each divided by a dividing line (11), which is a straight line substantially parallel to the straight side of the assembly (100) of solar cell units. The assembly of solar cell units includes: a photoelectric conversion portion (2) having a main surface; a transparent conductive layer (3) provided in regions corresponding to the plurality of small compartments (10) in the main surface of the photoelectric conversion portion (2), and having a first region and a second region that is different in position from the first region; a current collecting electrode (4) provided on the first region of the transparent conductive layer (3) and including an electroplated layer; a transparent insulating layer (5) provided on the second region of the transparent conductive layer (3), and the photoelectric conversion portion (2) is exposed in a dividing region (111) that is along the dividing line (11) and includes the dividing line.

Description

[0001] This application claims the priority of Japanese Patent Application No. 2020-060126, and the description thereof is incorporated herein by reference. Technical Field

[0002] The present invention relates to an assembly of battery cells, a method for manufacturing the assembly of battery cells, a solar cell unit formed from the assembly of battery cells, and a method for manufacturing the solar cell unit. The assembly of battery cells is a raw material for a solar cell unit, and a solar cell is formed by lap-connecting a plurality of solar cell units. Background Art

[0003] Conventionally, solar cells with various structures have been proposed. As such a solar cell, there is a solar cell module. In order to form a solar cell string, a plurality of rectangular solar cell units are connected to each other at their ends in a state where the long sides of adjacent solar cell units overlap each other in parallel, like laying roof tiles (Patent Document 1). In this solar cell module, by overlapping the solar cell units, there is no gap between adjacent solar cell units. Thus, the charging rate of the solar cell units in the solar cell module can be increased, and the module efficiency can be improved.

[0004] In addition, when forming a metal electrode of a solar cell, an electroplating method is known (Patent Document 2). This solar cell includes a photoelectric conversion part including a silicon substrate, a first transparent conductive layer and a transparent resin layer sequentially laminated on the light-receiving surface side of the photoelectric conversion part, and a second transparent conductive layer and a transparent resin layer sequentially laminated on the back side of the photoelectric conversion part. In this solar cell, the transparent resin layer has an opening, and a part of the surface of the first transparent conductive layer or the surface of the second transparent conductive layer is exposed from the opening of the transparent resin layer. In addition, this solar cell has an electroplated metal electrode laminated at a position where the surface of the first transparent conductive layer or the surface of the second transparent conductive layer exposed from the opening of the transparent resin layer. In this solar cell, the transparent resin layer functions as a mask when forming the electroplated metal electrode and functions as a protective layer of the completed solar cell.

[0005] When manufacturing the above-mentioned solar cell, when forming the electroplated metal electrode on the light-receiving surface side, first, the first transparent conductive layer and the transparent resin layer having an opening are sequentially laminated on the photoelectric conversion part. The shape of the opening of the transparent resin layer is formed corresponding to the shape of the electroplated metal electrode (that is, the pattern of the electroplated metal electrode). Then, the electroplated metal electrode is deposited on the first transparent conductive layer exposed from the opening of the transparent resin layer by electrolytic electroplating. In addition, the same process is performed when forming the electroplated metal electrode on the back side.

[0006] Prior Art Documents

[0007] Patent document

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-517145

[0009] Patent Document 2: Chinese Patent Application Laid-Open No. 2019 / 003818

[0010] Therefore, it is considered to apply a solar cell unit having the above-described electroplated metal electrode to a solar cell module configured by overlapping solar cell units as described above, that is, a solar cell module formed by shingling connection. In this case, in order to obtain a plurality of rectangular solar cell units, it is necessary to cut a cell unit aggregate having the above-described electroplated metal electrode by laser cutting. However, since the transparent resin layer in the cell unit aggregate absorbs laser light, it is impossible to completely cut the transparent resin layer, making it difficult to obtain the divided solar cell units. Summary of the Invention

[0011] An object of the present invention is to provide a cell unit aggregate, a method for manufacturing the cell unit aggregate, a solar cell unit formed from the cell unit aggregate, and a method for manufacturing the solar cell unit. The cell unit aggregate is a raw material for a solar cell unit, and a solar cell is formed by shingling connection of a plurality of solar cell units. The cell unit aggregate includes a metal electrode formed by an electroplating method and is easily cut.

[0012]

Means for Solving the Problem

[0013] The cell unit aggregate of the solar cell of the present invention is a cell unit aggregate of a solar cell having a plurality of small regions that are respectively divided into a plurality of solar cell units and having a side that is linearly shaped in a plan view. The plurality of small regions are respectively divided by a dividing line, which is a straight line substantially parallel to the linear side of the cell unit aggregate. The cell unit aggregate has: a photoelectric conversion portion having a main surface; a transparent conductive layer provided in a region corresponding to each of the plurality of small regions in the main surface of the photoelectric conversion portion, and having a first region and a second region having a different position from the first region; a current collecting electrode provided on the first region of the transparent conductive layer and including an electroplated layer; a transparent insulating layer provided on the second region of the transparent conductive layer, and the photoelectric conversion portion is exposed in a region along the dividing line and including the dividing line, that is, a dividing region.

[0014] Method for manufacturing an assembly of solar cell units of a solar cell, the assembly of solar cell units of the solar cell having a plurality of small compartments that are each divided to become a plurality of solar cell units and having a straight side when viewed from above, the plurality of small compartments being respectively divided by straight lines, i.e., dividing lines, that are substantially parallel to the side of the assembly of solar cell units, the method for manufacturing the assembly of solar cell units of the solar cell including: a step of preparing a photoelectric conversion part having a main surface; a step of forming a transparent conductive layer in regions corresponding to the plurality of small compartments in the main surface of the photoelectric conversion part; a step of forming a transparent insulating layer having an opening for exposing a part of the transparent conductive layer in the transparent conductive layer; a step of forming a current collecting electrode on the transparent conductive layer exposed from the opening by electroplating, the step of forming the transparent conductive layer, the step of forming the transparent insulating layer, and the step of forming the current collecting electrode being performed in a dividing region along and including the dividing line in such a manner that the photoelectric conversion part is exposed.

[0015] The solar cell unit of the present invention can form a solar cell string by overlapping and connecting a plurality of the solar cell units to each other. The solar cell unit has a straight side when viewed from above and a straight opposite side that is substantially parallel to the side. The solar cell unit has: a photoelectric conversion part having a main surface; a transparent conductive layer provided on the main surface of the photoelectric conversion part, which has a first region and a second region having a different position from the first region; a current collecting electrode provided on the first region of the transparent conductive layer and including an electroplated layer; and a transparent insulating layer provided on the second region of the transparent conductive layer, and the photoelectric conversion part is exposed at the side and the opposite side.

[0016] The method for manufacturing a solar cell unit of the present invention is a method for manufacturing a solar cell unit using the assembly of solar cell units of the solar cell according to claim 1, and includes a step of cutting the assembly of solar cell units by irradiating a laser to the dividing line. Description of the Drawings

[0017] Figure 1A is a top view of the assembly of solar cell units of the solar cell of the present embodiment.

[0018] Figure 1B is a bottom view of the assembly of solar cell units of the solar cell of the present embodiment.

[0019] Figure 2 is Figure 1A an enlarged cross-sectional view taken at the II-II position of

[0020] Figure 3A is a top view of the photoelectric conversion part of the assembly of solar cell units.

[0021] Figure 3B isFigure 3A An enlarged cross-sectional view taken along the line III-III.

[0022] Figure 4A is a top view of the photoelectric conversion portion formed with a transparent conductive layer.

[0023] Figure 4B is a bottom view of the photoelectric conversion portion formed with a transparent conductive layer.

[0024] Figure 5 is Figure 4A An enlarged cross-sectional view taken along the line V-V.

[0025] Figure 6A is a top view of the photoelectric conversion portion formed with a transparent insulating layer.

[0026] Figure 6B is a bottom view of the photoelectric conversion portion formed with a transparent insulating layer.

[0027] Figure 7 is Figure 6A An enlarged cross-sectional view taken along the line VII-VII.

[0028] Figure 8A is a top view of the solar cell unit of the present embodiment.

[0029] Figure 8B is a bottom view of the solar cell unit.

[0030] Figure 9 is Figure 8A A cross-sectional view taken along the line IX-IX.

[0031] Figure 10 is a schematic cross-sectional view of a solar cell string using the solar cell unit. Detailed Embodiment

[0032] Regarding the present invention, one embodiment will be cited and described below with reference to the accompanying drawings. In addition, the "solar cell unit" in the following description refers to the name of each plate-like portion constituting the "solar cell string". Further, the accompanying drawings schematically show the structure of the present embodiment and are different from design drawings. Therefore, the dimensional relationships in the drawings may not necessarily be accurate.

[0033] As Figure 1A and Figure 1BAs shown, the cell aggregate 100 of the solar cell according to the present embodiment (hereinafter, simply referred to as "cell aggregate 100") is a cell aggregate of a solar cell having a plurality of small compartments 10, and the plurality of small compartments 10 are each divided into a plurality of solar cell units 1. In addition, the cell aggregate 100 has a side (side 100a) that is linear when viewed from above. The plurality of small compartments 10 are each divided by a dividing line 11, which is a straight line substantially parallel to the side 100a of the cell aggregate 100.

[0034] As Figure 2 shown, the cell aggregate 100 includes: a photoelectric conversion portion 2 having a main surface 20; a transparent conductive layer 3 provided in a region 200 corresponding to each of the plurality of small compartments 10 in the main surface 20 of the photoelectric conversion portion 2; a current collecting electrode 4 provided on a first region 31 of the transparent conductive layer 3 and including an electroplated layer 40; and a transparent insulating layer 5 provided on a second region 32 that is at a different position from the first region 31 of the transparent conductive layer 3. In the cell aggregate 100 of the present embodiment, the respective layers are stacked in the Figure 2 z-axis direction. In addition, in a dividing region 111, which is a region along and including the dividing line 11 of the cell aggregate 100, the photoelectric conversion portion 2 is exposed. Further, the main surface 20 is the main surface of the plate-like surface constituting the photoelectric conversion portion 2. In addition, the photoelectric conversion portion 2 has a side surface (end surface) as an edge.

[0035] The cell aggregate 100 of the present embodiment has a plurality of dividing lines 11 and a plurality of dividing regions 111. Specifically, the cell aggregate 100 has three dividing lines 11 and three dividing regions 111 (see Figure 1A and Figure 1B ). In addition, in the cell aggregate 100, the dividing lines 11 extend in the y-axis direction and are arranged at equal intervals in the x-axis direction.

[0036] The dividing region 111 of the present embodiment extends in the y-axis direction. The widths (for example, dimensions in the x-axis direction) of the plurality of dividing regions 111 are all the same. The dividing regions 111 extend on both sides of the dividing line 11 in the x-axis direction. In each dividing region 111, for example, the distance between the edge 111a on one side in the x-axis direction of the dividing region 111 ( Figure 1A and Figure 2 the right side) and the dividing line 11 is the same as the distance between the edge 111b on the other side in the x-axis direction of the dividing region 111 ( Figure 1A and Figure 2 the left side) and the dividing line 11. That is, the dividing line 11 extends in the center of the width direction (for example, the x-axis direction) of each dividing region 111.

[0037] The photoelectric conversion unit 2 is, for example, a plate-shaped component. In addition, the photoelectric conversion unit 2 has a pn junction or a pin junction. The photoelectric conversion unit 2 of the present embodiment has a conductive type crystalline silicon substrate 21 (hereinafter, also referred to as "silicon substrate 21") (see Figure 2 ). In addition, the photoelectric conversion unit 2 has a pn junction formed between the conductive type silicon-based thin films 22 and 23. Moreover, the photoelectric conversion unit 2 of the present embodiment further has intrinsic silicon-based thin films 24 and 25 provided between the silicon substrate 21 and the conductive type silicon-based thin films 22 and 23.

[0038] The silicon substrate 21 is, for example, either an n-type crystalline silicon substrate or a p-type crystalline silicon substrate. The silicon substrate 21 of the present embodiment is, for example, an n-type single crystal silicon substrate.

[0039] On the first main surface 211 of the silicon substrate 21 ( Figure 2 the upper surface of the silicon substrate 21 in ) a first conductive type silicon-based thin film 22 is provided. On the second main surface 212 of the silicon substrate 21 ( Figure 2 the lower surface of the silicon substrate 21 in ) a second conductive type silicon-based thin film 23 is provided.

[0040] One of the first conductive type silicon-based thin film 22 and the second conductive type silicon-based thin film 23 is p-type, and the other is n-type. The first conductive type silicon-based thin film 22 of the present embodiment is p-type. In addition, the second conductive type silicon-based thin film 23 of the present embodiment is n-type. The film thicknesses of the first conductive type silicon-based thin film 22 and the second conductive type silicon-based thin film 23 are each 2 nm or more and 20 nm or less.

[0041] The transparent conductive layer 3 includes: a first transparent conductive layer 33 provided on the first main surface 201 side of the photoelectric conversion unit 2, and a second transparent conductive layer 34 provided on the second main surface 202 side of the photoelectric conversion unit 2. The material of the transparent conductive layer 3 is, for example, a conductive metal oxide such as ITO (indium tin oxide). The film thickness of the transparent conductive layer 3 is, for example, 20 nm or more and 120 nm or less.

[0042] The current collecting electrode 4 is a patterned metal electrode. The current collecting electrode 4 of the present embodiment is composed of an electroplated layer 40. In addition, the current collecting electrode 4 of the present embodiment has: a first current collecting electrode 41 provided on the first main surface 201 ( Figure 2 the upper surface of the photoelectric conversion unit 2 in ) of the photoelectric conversion unit 2, and a second current collecting electrode 42 provided on the second main surface 202 ( Figure 2 the lower surface of the photoelectric conversion unit 2 in ).

[0043] For example, the current collecting electrode 4 has a plurality of finger electrodes 43 extending in parallel with each other, and bus bar electrodes 4, 4 extending in a manner intersecting (specifically, orthogonal) to the finger electrodes 43 (see Figure 1A and Figure 1B)。In the current collector electrode 4 of the present embodiment, the finger electrodes 43 and the bus bar electrodes 41 and 42 constitute a pattern electrode on the gate. The thickness of the current collector electrode 4 is, for example, 10 μm or more and 30 μm or less.

[0044] The shape of the second current collector electrode 42 is, for example, the same as the shape of the first current collector electrode 41. In addition, the shape of the second current collector electrode 42 may also be different from the shape of the first current collector electrode 41.

[0045] The plating layer 40 is adjacent to the divided region 111 where the photoelectric conversion unit 2 is exposed. Specifically, the plating layer 40 is juxtaposed with the divided region 111 where the photoelectric conversion unit 2 is exposed in the x-axis direction.

[0046] The transparent insulating layer 5 functions as a mask when forming the plating layer 40. In addition, the transparent insulating layer 5 also functions as a protective layer on the surface of the completed battery cell assembly 100 and the solar cell unit 1.

[0047] An opening 50 including the region where the current collector electrode 4 is formed is provided on the transparent insulating layer 5 ( Figure 2 see reference). That is, an opening 50 is provided on the transparent insulating layer 5 to expose the first region 31 of the transparent conductive layer 3. Moreover, the transparent insulating layer 5 covers one end 36 of the two ends of the transparent conductive layer 3 in the extending direction of the finger electrode 43 ( Figure 2 the x-axis direction in this case) and exposes the other end 35.

[0048] The material of the transparent insulating layer 5 in the present embodiment is, for example, a resin with light transmittance. This material preferably has resin thermosetting or photocuring properties. The thickness of the transparent insulating layer 5 is preferably, for example, 5 μm or more and 30 μm or less, more preferably 8 μm or more and 20 μm or less. In addition, the thickness of the transparent insulating layer 5 is, for example, the distance from the surface of the transparent conductive layer 3 to the surface of the transparent insulating layer 5 at the position with the maximum thickness.

[0049] The manufacturing method of the battery cell assembly 100 configured as described above includes the following steps: a step of preparing the photoelectric conversion unit 2 having the main surface 20; a step of forming the transparent conductive layer 3 in the regions 200 corresponding to the respective small divisions in the main surface 20 of the photoelectric conversion unit 2; a step of forming the transparent insulating layer 5 having an opening 50 for exposing a part of the transparent conductive layer 3 on the transparent conductive layer 3; a step of forming the current collector electrode 4 on the transparent conductive layer 3 exposed from the opening by electroplating. In this manufacturing method, the steps of forming the transparent conductive layer 3, forming the transparent insulating layer 5, and forming the current collector electrode 4 are performed in the divided region 111 in such a manner that the photoelectric conversion unit 2 is exposed. Hereinafter, each step will be specifically described with reference to FIGS. 3 to 8.

[0050] For example, asFigure 3A and Figure 3B As shown in Figure 3A and Figure 3B , the process of preparing the photoelectric conversion unit 2 includes the process of forming silicon-based thin films 22 and 23 on the silicon substrate 21. Specifically, the process of preparing the photoelectric conversion unit 2 includes not only the process of forming silicon-based thin films 22 and 23, but also the process of forming silicon-based thin films 24 and 25.

[0051] The silicon substrate 21 is, for example, a 6-inch n-type single crystal silicon substrate. The silicon-based thin films 22, 23, 24, and 25 are provided in the entire regions of the first main surface 211 and the second main surface 212 of the silicon substrate 21. In addition, the silicon-based thin films 22, 23, 24, and 25 are formed, for example, by plasma CVD method.

[0052] As Figure 4A , Figure 4B and Figure 5 As shown in Figure 4A , Figure 4B , and Figure 5 , the process of forming the transparent conductive layer 3 includes: the process of forming the first transparent conductive layer 33 on the first main surface 201 of the photoelectric conversion unit 2; the process of forming the second transparent conductive layer 34 on the second main surface 202 of the photoelectric conversion unit 2. Specifically, the process of forming the transparent conductive layer 3 includes: the process of forming the first transparent conductive layer 33 on the side opposite to the side of the first conductive type silicon-based thin film 22 relative to the silicon substrate 21 (the side in contact with the silicon substrate 21); the process of forming the second transparent conductive layer 34 on the side opposite to the side of the second conductive type silicon-based thin film 23 relative to the silicon substrate 21 (the side in contact with the silicon substrate 21).

[0053] Through the process of forming the transparent conductive layer 3, the transparent conductive layer 3 is formed in a rectangular shape extending in the y-axis direction. In addition, the transparent conductive layers 3 are formed so as to be arranged at intervals in the x-axis direction. Thus, the transparent conductive layer 3 is formed so as to expose the portion of the photoelectric conversion unit 2 that becomes the divided region 111 of the battery unit aggregate 100. The transparent conductive layer 3 is formed, for example, by MOCVD method or sputtering method.

[0054] As Figure 6A , Figure 6B , and Figure 7 As shown in Figure 6A , Figure 6B , and Figure 7 , the process of forming the transparent insulating layer 5 includes: the process of printing a resin solution on the transparent conductive layer 3; the process of forming an opening 50 in the printed resin layer and thereby forming the transparent insulating layer 5. This resin solution is, for example, an acrylic resin solution. The solution viscosity of this acrylic resin solution at room temperature (25 °C) is adjusted to be 70 Pa·s or more and 120 Pa·s or less.

[0055] In addition, when the resin material constituting the transparent insulating layer 5 is a material having thermosetting properties or photocuring properties, preferably, in the process of forming the transparent insulating layer 5, after printing a resin solution on the transparent conductive layer 3 by screen printing or the like, the transparent insulating layer 5 is cured before the process of forming the current collecting electrode 4.

[0056] In the process of forming the transparent insulating layer 5, the transparent insulating layer 5 is formed into a rectangle extending in the y-axis direction. In addition, the transparent insulating layer 5 is formed in such a manner that it is arranged at intervals (openings 50) in the x-axis direction. Thus, the transparent insulating layer 5 is formed so as to expose the portion of the photoelectric conversion unit 2 that becomes the divided region 111 of the battery cell assembly 100.

[0057] The process of forming the current collecting electrode 4 includes a process of forming an electroplated layer 40 on the transparent conductive layer 3 exposed under the opening 50 of the transparent insulating layer 5 by an electroplating method (see Figure 1A , Figure 1B , and Figure 2 ). Specifically, the process of forming the electroplated layer 40 includes: a process of depositing a first electroplated layer on the transparent conductive layer 3 exposed under the opening 50 of the transparent insulating layer 5 by electrolytic electroplating; a process of depositing a second electroplated layer on the first electroplated layer by electrolytic electroplating. When depositing the first electroplated layer, for example, Ni is used, and when depositing the second electroplated layer, for example, Cu is used.

[0058] Through the process of forming the current collecting electrode 4, the current collecting electrode 4 is formed to have a plurality of finger electrodes 43 extending parallel to each other, and bus bar electrodes 4, 4 extending intersecting (specifically, orthogonally) with the finger electrodes 43. In addition, the current collecting electrode 4 is formed on the transparent conductive layer 3 exposed under the opening 50 of the transparent insulating layer 5. Thus, the current collecting electrode 4 is formed so as to expose the portion of the photoelectric conversion unit 2 that becomes the divided region 111 of the battery cell assembly 100.

[0059] The battery cell assembly 100 manufactured by the above manufacturing method is cut, and thus the solar cell unit 1 can be manufactured. The manufacturing method of the solar cell unit 1 includes a process of cutting the battery cell assembly 100 by irradiating a laser on the dividing line 11.

[0060] As Figure 8A , Figure 8B , and Figure 9As shown, the solar cell unit 1 has a linear side 1a and a linear opposite side 1b that is substantially parallel to the side 1a. The solar cell unit 1 includes: a photoelectric conversion portion 2 having a main surface 20; a transparent conductive layer 3 provided on the main surface 20 of the photoelectric conversion portion 2; a current collecting electrode 4 provided on a first region 31 of the transparent conductive layer 3 and including an electroplated layer 40; and a transparent insulating layer 5 provided on a second region 32 of the transparent conductive layer 3 that is different from the first region 31. In the side 1a and the opposite side 1b, the photoelectric conversion portion 2 is exposed.

[0061] In plan view, the solar cell unit 1 of the present embodiment is rectangular (substantially rectangular). In addition, the solar cell unit 1 is, for example, a bifacial solar cell unit.

[0062] In addition, as Figure 10 shown, a solar cell string 101 can be formed by overlapping and connecting a plurality of solar cell units 1 to each other. In addition, the overlapping connection means a method of connecting the adjacent solar cell units 1, 1 in a state where the first current collecting electrode 41 of one of the adjacent solar cell units 1 overlaps with the second current collecting electrode 42 of the other solar cell unit 1. In this overlapping connection, the current collecting electrodes 40 of the adjacent solar cell units 1, 1 are connected to each other by a conductive adhesive 6 (see Figure 10 ). The conductive adhesive 6 is, for example, a metal paste, and specifically, a silver paste.

[0063] Through the above-described solar cell unit assembly 100, in the divided region 111, the photoelectric conversion portion 2 is exposed (see Figure 2 ). That is, in a certain position (divided region 111) of the dividing line 11, since the main surface 20 of the photoelectric conversion portion 2 is not covered by the transparent insulating layer 5 and the electroplated layer 40, the solar cell unit assembly 100 can be easily cut by irradiating the dividing line 11 with laser light only.

[0064] Through the manufacturing method of the cell unit assembly 100 of the present embodiment, a cell unit assembly 100 can be manufactured in which, in a certain position (divided region 111) of the dividing line 11, since the main surface 20 of the photoelectric conversion portion 2 is not covered by the transparent insulating layer 5 and the electroplated layer 40, the cell unit assembly can be easily cut by irradiating the dividing line 11 with laser light only.

[0065] In addition, the solar cell unit 1 of the present embodiment can be easily obtained by irradiating laser light on a position of the main surface 20 of the photoelectric conversion portion 2 of the solar cell unit assembly 100 that is not covered by the transparent insulating layer 5 and the electroplated layer 40 and dividing the cell unit assembly 100.

[0066] Moreover, by the manufacturing method of the solar cell unit 1 of the present embodiment, by irradiating a laser on the positions in the photoelectric conversion part 2 of the cell unit aggregate 100 of the solar cell that are not covered by the transparent insulating layer 5 and the plating layer 40, and dividing the cell unit aggregate 100, the solar cell unit 1 can be easily obtained.

[0067] In addition, the cell unit aggregate or the solar cell unit of the present invention is not limited to the above-described embodiments, and various changes can of course be added without departing from the gist of the present invention. For example, the structure of other embodiments can be added to the structure of a certain embodiment, and in addition, a part of the structure of a certain embodiment can be replaced with the structure of other embodiments. Moreover, a part of the structure of a certain embodiment can be deleted.

[0068] In the cell unit aggregate 100 of the above-described embodiment, the dividing line 11 extends in the center of the width direction (for example, the x-axis direction) of each dividing region 111, but as long as the dividing line 11 is included in each dividing region 111, the extending position can be any position. Even when the dividing line 11 extends at a position offset in the width direction of the dividing region 111, by cutting the cell unit aggregate 100 along the dividing line 11, the solar cell unit 1 can be obtained. In addition, the widths of the plurality of dividing regions 111 provided on the cell unit aggregate 100 can also be different.

[0069] The materials and shapes of the respective layers constituting the cell unit aggregate 100 and the solar cell unit 1 are not limited to the content of the above-described embodiments. For example, the plating layer 40 of the current collecting electrode 4 has a two-layer structure, but a third plating layer formed by electrolytic plating or electroless plating (including displacement plating) can also be provided on the second plating layer made of CU. In addition, the current collecting electrode 4 can include an electrode layer formed by a method other than the plating method in addition to the plating layer 40.

[0070] In addition, the solar cell unit 1 can also be a single-sided light-receiving type.

[0071] In addition, for the solar cell unit 1 of the present embodiment, the cell unit aggregate 100 is cut by irradiating a laser on the dividing line 11, but the method of dividing the cell unit aggregate 100 is not limited to the method of cutting by laser. For example, a groove can also be formed along the dividing line 11 of the cell unit aggregate 100 by laser or mechanical scribing, and the cell unit aggregate 100 can be divided along the groove to obtain the solar cell unit 1. Even in this case, since the transparent insulating layer 5 and the plating layer 40 do not exist on the dividing line 11, it is easy to form a groove and easy to divide the cell unit aggregate 100 into the solar cell unit 1.

[0072] As described above, according to the present invention, it is possible to provide an assembly of solar cell units as a raw material for a solar cell unit, a method for manufacturing the assembly of solar cell units, a solar cell unit formed from the assembly of solar cell units, and a method for manufacturing the solar cell unit, in which a solar cell is formed by lap-connecting a plurality of solar cell units, and the assembly of solar cell units includes a metal electrode formed by an electroplating method and is easily cut.

[0073] The assembly of solar cell units of the solar cell according to the present invention is an assembly of solar cell units of a solar cell having a plurality of small compartments that are each divided into a plurality of solar cell units and having a straight side when viewed from above, and the plurality of small compartments are each divided by a dividing line, which is a straight line substantially parallel to the straight side of the assembly of solar cell units. The assembly of solar cell units has: a photoelectric conversion part having a main surface; a transparent conductive layer provided in a region corresponding to each of the plurality of small compartments on the main surface of the photoelectric conversion part and having a first region and a second region different in position from the first region; a current collecting electrode provided on the first region of the transparent conductive layer and including an electroplated layer; and a transparent insulating layer provided on the second region of the transparent conductive layer. In a dividing region that is along the dividing line and includes the dividing line, the photoelectric conversion part is exposed.

[0074] According to this structure, in the position (dividing region) having the dividing line, since the main surface of the photoelectric conversion part is not covered with the transparent insulating layer or the electroplated layer, the assembly of solar cell units can be easily cut only by irradiating the dividing line with a laser.

[0075] A method for manufacturing an assembly of solar cell units of a solar cell according to the present invention, the assembly of solar cell units of the solar cell having a plurality of small compartments that are each divided into a plurality of solar cell units and having a straight side when viewed from above, and the plurality of small compartments are each divided by a dividing line, which is a straight line substantially parallel to the side of the assembly of solar cell units. The method includes: a step of preparing a photoelectric conversion part having a main surface; a step of forming a transparent conductive layer in a region corresponding to each of the plurality of small compartments on the main surface of the photoelectric conversion part; a step of forming a transparent insulating layer having an opening for exposing a part of the transparent conductive layer in the transparent conductive layer; a step of forming a current collecting electrode by an electroplating method on the transparent conductive layer exposed from the opening. The steps of forming the transparent conductive layer, forming the transparent insulating layer, and forming the current collecting electrode are performed in such a manner that the photoelectric conversion part is exposed in a dividing region that is along the dividing line and includes the dividing line.

[0076] According to this structure, in the position (partition region) where the dividing line is located, since the main surface of the photoelectric conversion portion is not covered by the transparent insulating layer and the plating layer, it is possible to manufacture a solar cell unit assembly of a solar cell that can be easily cut by irradiating the dividing line with a laser.

[0077] The solar cell unit of the present invention can form a solar cell string by connecting a plurality of solar cell units to overlap each other, and has a straight side when viewed from above and a straight opposite side substantially parallel to the side, and has: a photoelectric conversion portion having a main surface; a transparent conductive layer provided on the main surface of the photoelectric conversion portion and having a first region and a second region with a different position from the first region; a current collecting electrode provided on the first region of the transparent conductive layer and containing a plating layer; a transparent insulating layer provided on the second region of the transparent conductive layer, and in the side and the opposite side, the photoelectric conversion portion is exposed.

[0078] The manufacturing method of the solar cell unit with this structure can be easily obtained by irradiating a laser on the position of the main surface of the photoelectric conversion portion of the solar cell unit assembly of the solar cell that is not covered by the transparent insulating layer and the plating layer to divide the unit assembly.

[0079] The manufacturing method of the solar cell unit of the present invention is a manufacturing method of a solar cell unit using a solar cell unit assembly of a solar cell, and includes a process of cutting the unit assembly by irradiating a laser on the dividing line.

[0080] According to this structure, by irradiating a laser on the position of the photoelectric conversion portion of the solar cell unit assembly of the solar cell that is not covered by the transparent insulating layer and the plating layer to divide the unit assembly, thus, a solar cell unit can be easily obtained.

[0081]

Explanation of reference numerals

[0082] 1…Solar cell unit, 1a…One side, 1b…Opposite side, 2…Photovoltaic conversion section, 3…Transparent conductive layer, 4…Collecting electrode, 5…Transparent insulating layer, 6…Conductive adhesive, 10…Cell division, 11…Division line, 20…Main surface, 21…Conductive type crystalline silicon substrate (silicon substrate), 22…First conductive type silicon-based thin film (conductive type silicon-based thin film, silicon-based thin film), 23…Second conductive type silicon-based thin film (conductive type silicon-based thin film, silicon-based thin film), 24, 25…Intrinsic silicon-based thin film (silicon-based thin film), 31…First region, 32…Second region, 33…First transparent conductive layer, 34…Second transparent conductive layer, 35, 36…Ends, 40…Plated layer, 41…First collecting electrode, 42…Second collecting electrode, 43…Finger electrode, 44…Bus bar electrode, 50…Opening, 100…Aggregate of cell units, 100a…Side, 101…Solar cell string, 111…Division region, 111a, 111b…Edge, 200…Region, 201…First main surface, 202…Second main surface, 211…First main surface, 212…Second main surface.

Claims

1. An integrated cell unit of a solar cell is a cell unit assembly of a solar cell having a plurality of small compartments that are each divided into a plurality of solar cell units and having a side that is linearly shaped in a top view. The plurality of small compartments are each divided by a dividing line, which is a straight line substantially parallel to the linearly shaped side of the cell unit assembly. The cell unit assembly of the solar cell has: A photoelectric conversion portion having a main surface; A transparent conductive layer provided in a region corresponding to each of the plurality of small compartments on the main surface of the photoelectric conversion portion, and having a first region and a second region that is different in position from the first region; A current collecting electrode provided on the first region of the transparent conductive layer and including an electroplated layer; A transparent insulating layer provided on the second region of the transparent conductive layer; The current collecting electrode has a plurality of finger electrodes extending parallel to each other and a bus bar electrode extending in a manner intersecting the plurality of finger electrodes; The transparent insulating layer covers one end of the two ends of the transparent conductive layer in the extending direction of the plurality of finger electrodes and exposes the other end; The photoelectric conversion portion is exposed in a dividing region that is along the dividing line and includes the dividing line.

2. A method for manufacturing a cell unit assembly of a solar cell, the cell unit assembly of the solar cell having a plurality of small compartments that are each divided into a plurality of solar cell units and having a side that is linearly shaped in a top view, and the plurality of small compartments are each divided by a dividing line, which is a straight line substantially parallel to the side of the cell unit assembly. The method for manufacturing the cell unit assembly of the solar cell includes: A step of preparing a photoelectric conversion portion having a main surface; A step of forming a transparent conductive layer in a region corresponding to each of the plurality of small compartments on the main surface of the photoelectric conversion portion; A step of forming a transparent insulating layer having an opening for exposing a part of the transparent conductive layer on the transparent conductive layer; A step of forming a current collecting electrode having a plurality of finger electrodes extending parallel to each other and a bus bar electrode extending in a manner intersecting the plurality of finger electrodes on the transparent conductive layer exposed from the opening by an electroplating method; The step of forming the transparent conductive layer, the step of forming the transparent insulating layer, and the step of forming the current collecting electrode are performed in a dividing region that is along the dividing line and includes the dividing line in such a manner that the photoelectric conversion portion is exposed, and the transparent insulating layer covers one end of the two ends of the transparent conductive layer in the extending direction of the plurality of finger electrodes and exposes the other end.

3. A solar cell unit, which can form a solar cell string by connecting a plurality of the solar cell units in an overlapping manner. The solar cell unit has a side that is linearly shaped in a top view and a linearly shaped opposite side that is substantially parallel to the side. The solar cell unit has: A photoelectric conversion portion having a main surface; A transparent conductive layer provided on the main surface of the photoelectric conversion portion, which has a first region and a second region that is different in position from the first region; A current collecting electrode provided on the first region of the transparent conductive layer and including an electroplated layer; A transparent insulating layer is provided on the second region of the transparent conductive layer. The current collecting electrode has a plurality of finger electrodes extending parallel to each other and a bus bar electrode extending in a manner intersecting the plurality of finger electrodes. The transparent insulating layer entirely covers one end of the two ends of the transparent conductive layer in the extending direction of the plurality of finger electrodes up to the end edge, and exposes the other end. The photoelectric conversion portion is exposed in the one side and the opposite side.

4. A method for manufacturing a solar cell unit, which is a method for manufacturing a solar cell unit using a solar cell unit assembly of the solar cell according to claim 1. The method includes a step of cutting the cell unit assembly by irradiating a laser beam onto the dividing line.

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