Solar cell, solar cell device, and method for manufacturing a solar cell device

Abstract

To provide a solar battery cell capable of easily inspecting the quality of coating of a conductive adhesion member.SOLUTION: A solar battery cell 2 comprises a first metal electrode 29 formed at the side of one principal surface of a semiconductor substrate 11 and a second metal electrode formed at the side of the other principal surface of the semiconductor substrate. The first metal electrode 29 includes a first bus bar electrode 29b extending in a Y direction at the side of one end in an X direction, and the second metal electrode includes a second bus bar electrode extending in the Y direction at the side of the other end in the X direction. An inspection region R1 or R2 for inspecting the quality of coating of a conductive adhesion member, the first bus bar electrode 29b or the second bus bar electrode not being formed in the inspection region, is disposed at least at one side of the end of the first bus bar electrode 29b or the second bus bar electrode in the Y direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a solar cell, a solar cell device, and a method for manufacturing a solar cell device.

Background Art

[0002] As a solar cell device including a plurality of solar cells, there is a solar cell device having a singling structure in which ends of adjacent solar cells are overlapped and connected (see, for example, Patent Document 1). In such a solar cell device having a singling structure, metal electrodes (for example, bus bar electrodes) at ends of adjacent solar cells are connected via a conductive adhesive member. As a method for manufacturing such a solar cell device having a singling structure, a conductive adhesive member (for example, conductive paste CP) is applied to one metal electrode of adjacent solar cells, and the metal electrodes of the adjacent solar cells are overlapped.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When applying a conductive adhesive member to a metal electrode of a solar cell, the application of the conductive adhesive member may be insufficient. If the application of the conductive adhesive member is thus insufficient, peeling or the like of the bonding portion may occur, and the reliability of the solar cell device may be reduced.

[0005] Regarding this point, it may be considered to confirm (inspect) the application state of the conductive adhesive member. However, for the following two reasons, it is actually difficult to confirm the application state of the conductive adhesive member. (1) The process from the conductive adhesive coating process to the solar cell device manufacturing process (i.e., the solar cell connection process) is carried out in a single device. Therefore, after the solar cell device is manufactured, i.e., after the solar cells are connected, it is difficult to non-destructively check (inspect) the coating state of the conductive adhesive between the solar cells. (2) Silver paste is known as a metal electrode, for example, and silver paste is also known as a conductive adhesive member, and the color tone of the metal electrode and the color tone of the conductive adhesive member are similar. Therefore, even if imaging is performed using an imaging device such as a camera after the conductive adhesive member coating process but before the solar cell device manufacturing process (i.e., the solar cell connection process), it is difficult to confirm (inspect) the coating state of the conductive adhesive member on the metal electrode layer.

[0006] The present invention aims to provide a solar cell, a solar cell device, and a method for manufacturing a solar cell device that allows for easy inspection of the quality of the application of a conductive adhesive member. [Means for solving the problem]

[0007] The solar cell according to the present invention comprises a first metal electrode formed on one main surface side of a semiconductor substrate and a second metal electrode formed on the other main surface side of the semiconductor substrate, wherein the first metal electrode includes a first busbar electrode extending in a second direction intersecting the first direction at one end in a first direction, and the second metal electrode includes a second busbar electrode extending in a second direction at the other end in the first direction, and at least one end of the first busbar electrode or the second busbar electrode in the second direction is provided with an inspection area for inspecting the quality of the application of a conductive adhesive member, the inspection area in which the first busbar electrode or the second busbar electrode is not formed.

[0008] The solar cell device according to the present invention comprises a plurality of solar cells and a conductive adhesive member, wherein the plurality of solar cells are arranged in the first direction and connected by overlapping portions of their ends using a single-ring method, and the first busbar electrode of one of the adjacent solar cells in the plurality of solar cells and the second busbar electrode of the other of the adjacent solar cells are connected via the conductive adhesive member.

[0009] The present invention relates to a solar cell device manufacturing method, which includes (i) a solar cell manufacturing step of manufacturing a plurality of solar cells, comprising a metal electrode layer formation step of forming a first metal electrode on one main surface side of a semiconductor substrate and forming a second metal electrode on the other main surface side of the semiconductor substrate, wherein the first metal electrode includes a first busbar electrode extending in a second direction intersecting the first direction at one end in a first direction, and the second metal electrode includes a second busbar electrode extending in the second direction at the other end in the first direction, (ii) a conductive adhesive member coating step of coating a conductive adhesive member onto the first busbar electrode or the second busbar electrode in each of the plurality of solar cells, (iii) an inspection step of inspecting the quality of the coating of the conductive adhesive member, and (iv) a solar cell connection step of connecting a plurality of good solar cells obtained in the inspection step using a single-ring method, thereby manufacturing a solar cell device. In the metal electrode formation process, an inspection area for inspecting the quality of the formation of the conductive adhesive member is placed on at least one side of the second end of the first busbar electrode or the second busbar electrode, where the first busbar electrode or the second busbar electrode is not formed. In the inspection process, the quality of the application of the conductive adhesive member is determined by the presence or absence of the conductive adhesive member in the inspection area. [Effects of the Invention]

[0010] According to the present invention, in the manufacture of a solar cell device that connects multiple solar cells, the quality of the application of the conductive adhesive member can be easily inspected.

Brief Description of the Drawings

[0011] [Figure 1] It is a view of a solar cell module including a solar cell device according to this embodiment as seen from the light-receiving surface side. [Figure 2] It is a sectional view taken along line II-II of the solar cell module and the solar cell device shown in FIG. 1. [Figure 3] It is a view of the solar cell according to this embodiment as seen from the light-receiving surface side. [Figure 4] It is a view of the solar cell according to this embodiment as seen from the back surface side. [Figure 5] It is a sectional view taken along line V-V of the solar cell shown in FIGS. 3 and 4. [Figure 6] 1]It is a sectional view taken along line VI-VI of the solar cell shown in FIGS. 3 and 4. [Figure 7] It is a view showing a metal electrode layer forming step included in the solar cell manufacturing step in the manufacturing method of the solar cell device according to this embodiment. [Figure 8] It is an enlarged view of part VIII in FIG. 7. [Figure 9] It is a view showing a step of applying a conductive adhesive member in the manufacturing method of the solar cell device according to this embodiment. [Figure 10] It is a view showing an inspection step in the manufacturing method of the solar cell device according to this embodiment. [Figure 11] It is an enlarged view of part XI shown in FIG. 10. [Figure 12] It is a view showing a solar cell connection step included in the solar cell device forming step in the manufacturing method of the solar cell device according to this embodiment. [Figure 13] It is a view of the solar cell according to a modification of this embodiment as seen from the light-receiving surface side. [Figure 14] It is an enlarged view of part XIV shown in FIG. 10.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, an example of an embodiment of the present invention will be described with reference to the accompanying drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals. For the sake of convenience, hatching, member numbers, etc. may be omitted, but in such cases, other drawings shall be referred to.

[0013] (Solar cell module) FIG. 1 is a view of a solar cell module including a solar cell device according to the present embodiment as seen from the light-receiving surface side, and FIG. 2 is a cross-sectional view taken along line II-II of the solar cell module and the solar cell device shown in FIG. 1. In FIG. 1, the light-receiving side protective member 3, the back side protective member 4, and the sealing material 5, which will be described later, are omitted. Also, in FIGS. 1 and 2, and the drawings to be described later, an XY orthogonal coordinate system is shown. The XY plane is a plane along the light-receiving surface and the back surface of the solar cell module.

[0014] As shown in FIGS. 1 and 2, the solar cell module 100 includes a solar cell device (also referred to as a solar cell string) 1 that electrically connects a plurality of solar cells 2 using a singling method.

[0015] The solar cell device 1 is sandwiched between a light-receiving side protective member 3 and a back side protective member 4. A liquid or solid sealing material 5 is filled between the light-receiving side protective member 3 and the back side protective member 4, whereby the solar cell device 1 is sealed.

[0016] The sealing material 5 seals and protects the solar cell device 1, that is, the solar cells 2, and is interposed between the light-receiving side surface of the solar cells 2 and the light-receiving side protective member 3, and between the back side surface of the solar cells 2 and the back side protective member 4. The shape of the sealing material 5 is not particularly limited, and for example, a sheet shape can be mentioned. This is because if it is in a sheet shape, it is easy to cover the front and back surfaces of the planar solar cells 2.

[0017] The material of the encapsulant 5 is not particularly limited, but it is preferable that it has the property of transmitting light (light transmission). Furthermore, it is preferable that the material of the encapsulant 5 has adhesive properties that allow the solar cell 2, the light-receiving protective member 3, and the back-side protective member 4 to adhere together. Examples of such materials include light-transmitting resins such as ethylene / vinyl acetate copolymer (EVA), ethylene / α-olefin copolymer, ethylene / vinyl acetate / triallyl isocyanurate (EVAT), polyvinyl butyrate (PVB), acrylic resin, urethane resin, or silicone resin.

[0018] The light-receiving protective member 3 protects the solar cell 2 by covering its surface (light-receiving surface) with the solar cell device 1, i.e., the solar cell 2, via the sealing material 5. The shape of the light-receiving protective member 3 is not particularly limited, but a plate or sheet shape is preferred because it indirectly covers the planar light-receiving surface.

[0019] The material of the light-receiving protective member 3 is not particularly limited, but like the sealing material 5, a material that is light-transmitting yet resistant to ultraviolet light is preferred. Examples include glass, or transparent resins such as acrylic resin or polycarbonate resin. The surface of the light-receiving protective member 3 may be processed to have an uneven surface, or it may be covered with an anti-reflective coating layer. This is because the light-receiving protective member 3 makes it difficult for the received light to be reflected, allowing more light to be guided to the solar cell device 1.

[0020] The back-side protective member 4 protects the solar cell 2 by covering its back surface via the sealing material 5. The shape of the back-side protective member 4 is not particularly limited, but like the light-receiving side protective member 3, it is preferably plate-shaped or sheet-shaped as it indirectly covers the surface back surface.

[0021] The material for the back protective member 4 is not particularly limited, but a material that prevents the intrusion of water, etc. (high water-resistant material) is preferred. Examples include resin films such as polyethylene terephthalate (PET), polyethylene (PE), olefin resins, fluororesins, or silicone resins, or laminates of a translucent plate-shaped resin member such as glass, polycarbonate, or acrylic and a metal foil such as aluminum foil.

[0022] (Solar cell devices) In the solar cell device 1, the solar cells 2 are connected in series by overlapping portions of their ends. Specifically, a portion of the light-receiving surface (one main surface) on one end (left end in Figure 2) of one of the adjacent solar cells 2, 2 overlaps with a portion of the back surface (other main surface) on the other end (right end in Figure 2) of the other solar cell 2 in the X direction (first direction). A first busbar electrode portion (described later) extending in the Y direction (second direction) is formed on a portion of the light-receiving surface on one end of the solar cell 2, and a second busbar electrode portion (described later) extending in the Y direction is formed on a portion of the back surface on the other end of the solar cell 2. The first busbar electrode portion on the light-receiving surface on one end of one solar cell 2 and the second busbar electrode portion on the back surface on the other end of the other solar cell 2 are electrically connected via a conductive adhesive member 6.

[0023] In this way, like roof tiles laid on a roof, multiple solar cells 2 form a stacked structure that is uniformly aligned and tilted in a certain direction. Therefore, this method of electrically connecting solar cells 2 is called the single-ring method. Multiple solar cells 2 connected in a string-like manner are called a solar cell string (solar cell device). In the following, the region where adjacent solar cells 2,2 overlap is called the overlapping region Ro.

[0024] Adjacent solar cells 2,2 are bonded together in the overlapping region Ro via a conductive adhesive member 6. The conductive adhesive member 6 is made of metal particles, low-melting-point metal nanoparticles, or a conductive paste (CP) formed from metal nanoparticles and a binder. From the viewpoint of reducing resistance, a silver paste containing silver as metal particles or metal nanoparticles is preferred as the conductive paste.

[0025] (Solar cells) Figure 3 is a view of the solar cell according to this embodiment from the light-receiving surface side, and Figure 4 is a view of the solar cell according to this embodiment from the back side. Figure 5 is a cross-sectional view of the solar cell shown in Figures 3 and 4 along line VV, and Figure 6 is a cross-sectional view of the solar cell shown in Figures 3 and 4 along line VI-VI. The solar cell 2 shown in Figures 3 to 6 is a rectangular double-sided electrode type solar cell. The solar cell 2 comprises a semiconductor substrate 11 having two main surfaces: a light-receiving surface side (one main surface side) and the opposite back side (the other main surface side). The solar cell 2 also comprises a first conductivity type semiconductor layer 25, a first transparent electrode layer 28, and a first metal electrode layer 29 formed sequentially on the light-receiving surface side (one surface side) of the semiconductor substrate 11. The solar cell 2 also comprises a second conductivity type semiconductor layer 35, a second transparent electrode layer 38, and a second metal electrode layer 39 formed on the back side (the other surface side) of the semiconductor substrate 11.

[0026] The semiconductor substrate 11 is formed from a crystalline silicon material such as single-crystal silicon or polycrystalline silicon. The semiconductor substrate 11 is, for example, an n-type semiconductor substrate in which an n-type dopant is doped into a crystalline silicon material. An example of an n-type dopant is phosphorus (P). The semiconductor substrate 11 functions as a photoelectric conversion substrate that absorbs incident light from the light-receiving surface side and generates photocarriers (electrons and holes).

[0027] By using crystalline silicon as the material for the semiconductor substrate 11, the dark current is relatively small, and relatively high output (stable output regardless of illuminance) can be obtained even when the intensity of incident light is low.

[0028] The first conductivity type semiconductor layer 25 is formed on the light-receiving side of the semiconductor substrate 11. On the other hand, the second conductivity type semiconductor layer 35 is formed on the back side of the semiconductor substrate 11.

[0029] The first conductivity type semiconductor layer 25 is formed from, for example, amorphous silicon material. The first conductivity type semiconductor layer 25 is a p-type semiconductor layer in which a p-type dopant is doped into, for example, amorphous silicon material. Examples of p-type dopants include boron (B).

[0030] The second conductivity type semiconductor layer 35 is formed from, for example, an amorphous silicon material. The second conductivity type semiconductor layer 35 is, for example, an n-type semiconductor layer in which an n-type dopant (for example, phosphorus (P) as described above) is doped into an amorphous silicon material.

[0031] Furthermore, the first conductivity type semiconductor layer 25 may be an n-type semiconductor layer, and the second conductivity type semiconductor layer 35 may be a p-type semiconductor layer. Also, the semiconductor substrate 11 may be a p-type semiconductor substrate in which a p-type dopant (for example, the boron (B) mentioned above) is doped into a crystalline silicon material.

[0032] A passivation layer may be formed between the first conductivity type semiconductor layer 25 and the light-receiving surface of the semiconductor substrate 11, and a passivation layer may also be formed between the first conductivity type semiconductor layer 25 and the back surface of the second conductivity type semiconductor layer 35. The passivation layer is formed of, for example, an intrinsic (type i) amorphous silicon material. The passivation layer suppresses the recombination of carriers generated in the semiconductor substrate 11 and improves the carrier recovery efficiency.

[0033] The first transparent electrode layer 28 is formed on the first conductive semiconductor layer 25, that is, on the light-receiving side of the semiconductor substrate 11. The second transparent electrode layer 38 is formed on the second conductive semiconductor layer 35, that is, on the back side of the semiconductor substrate 11. The first transparent electrode layer 28 and the second transparent electrode layer 38 are formed from a transparent conductive material. Examples of transparent conductive materials include ITO (Indium Tin Oxide) and ZnO (Zinc Oxide).

[0034] The first metal electrode layer 29 is formed on the first transparent electrode layer 28, that is, on the light-receiving side of the semiconductor substrate 11. The second metal electrode layer 39 is formed on the second transparent electrode layer 38, that is, on the back side of the semiconductor substrate 11.

[0035] The first metal electrode layer 29 has a so-called comb-like shape and includes a plurality of first finger electrode portions 29f corresponding to the teeth of a comb, and a first busbar electrode portion 29b corresponding to the support portion of the comb teeth, to which one end of the plurality of first finger electrode portions 28f is connected. The first busbar electrode portion 29b extends in the Y direction (second direction) along the edge of one end (left end in Figures 3 to 6) in the X direction (first direction) of the semiconductor substrate 11, and the first finger electrode portion 29f extends in the X direction from the first busbar electrode portion 29b.

[0036] Similarly, the second metal electrode layer 39 has a so-called comb-like shape and includes a plurality of second finger electrode portions 39f corresponding to the teeth of a comb, and a second busbar electrode portion 39b corresponding to the support portion of the comb teeth, to which one end of the plurality of second finger electrode portions 38f is connected. The second busbar electrode portion 39b extends in the Y direction (second direction) along the edge on the other end side (right end side in Figures 3 to 6) opposite the edge on the one end side in the X direction (first direction) of the semiconductor substrate 11, and the second finger electrode portion 39f extends from the second busbar electrode portion 39b in the X direction.

[0037] Furthermore, a first busbar electrode portion 29b or a second busbar electrode portion 39b is formed in the overlapping region Ro.

[0038] The first metal electrode layer 29 and the second metal electrode layer 39 are formed from a metallic material. For example, silver (Ag) is used as the metallic material. The material for the first metal electrode layer 29 and the second metal electrode layer 39 is a conductive paste formed from metal particles, low-melting-point metal nanoparticles, or metal nanoparticles and a binder. From the viewpoint of reducing resistance, a silver paste containing silver as metal particles or metal nanoparticles is preferred as the conductive paste.

[0039] As shown in Figure 3, inspection areas R1 for inspecting the quality of the application of the conductive adhesive member 6 are provided at both ends of the first busbar electrode portion 29b of the first metal electrode layer 29 in the Y direction (second direction). Note that the inspection areas R1 may be provided at only one of the two ends of the first busbar electrode portion 29b in the Y direction.

[0040] When screen printing, for example, is used as the coating method for the conductive adhesive member 6, coating defects may occur at the beginning or end of printing, that is, coating defects may occur at at least one end of the busbar electrode portion. Furthermore, delamination of the conductive adhesive member 6 occurs from the ends. For this reason, it is preferable to place the inspection area at the end of the busbar electrode portion.

[0041] The inspection area R1 is located within the area at the end of the first busbar electrode portion 29b. The shape of the inspection area R1 is not particularly limited and may be circular, elliptical, or rectangular, for example. The size (area) of the inspection area R1 is approximately 0.5 mm, from the viewpoint of the electrical resistance of the busbar electrode portion (line width approximately 1.0 mm) and the adhesion between the busbar electrode portion and the conductive adhesive member. 2 The following is preferable. On the other hand, the size (area) of the inspection area R1 should be 0.1 mm from the viewpoint of the accuracy of the inspection device (e.g., imaging device). 2 It is preferable if the above conditions are met.

[0042] In the inspection area R1, the first busbar electrode portion 29b is not formed. In other words, in the region of the first busbar electrode portion 29b, the first conductive semiconductor layer 25, the first transparent electrode layer 28, and the first metal electrode layer 29 are stacked in order from the semiconductor substrate 11 side, whereas in the inspection area R1, the first conductive semiconductor layer 25 and the first transparent electrode layer 28 are stacked in order from the semiconductor substrate 11 side, and the first transparent electrode layer 28 is exposed. As a result, the area of ​​the first busbar electrode 29b is the color (or brightness) of the silver paste, while the inspection area R1 is approximately black.

[0043] Alternatively, as shown in Figure 4, inspection areas R2 for checking the quality of the application of the conductive adhesive member 6 may be provided at both ends of the second busbar electrode portion 39b of the second metal electrode layer 39 in the Y direction (second direction). Note that the inspection areas R2 may be provided at only one of the two ends of the second busbar electrode portion 39b in the Y direction.

[0044] The inspection area R2 is located within the area at the end of the second busbar electrode portion 39b. The shape of the inspection area R2 is not particularly limited and may be circular, elliptical, or rectangular, for example. The size (area) of the inspection area R2 is 0.5 mm², from the viewpoint of the electrical resistance of the busbar electrode portion and the adhesion between the busbar electrode portion and the conductive adhesive member. 2 The following is preferable. On the other hand, the size (area) of the inspection area R2 should be 0.1 mm from the viewpoint of the accuracy of the inspection device (e.g., imaging device). 2 It is preferable if the above conditions are met.

[0045] In inspection area R2, the second busbar electrode portion 39b is not formed. In other words, in the region of the second busbar electrode portion 39b, the second conductive semiconductor layer 35, the second transparent electrode layer 38, and the second metal electrode layer 39 are stacked in order from the semiconductor substrate 11 side, whereas in inspection area R2, the second conductive semiconductor layer 35 and the second transparent electrode layer 38 are stacked in order from the semiconductor substrate 11 side, and the second transparent electrode layer 38 is exposed. As a result, the area of ​​the second busbar electrode 39b is the color (or brightness) of the silver paste, while the inspection area R2 is approximately black.

[0046] (Method of manufacturing solar cell devices) Next, the method for manufacturing a solar cell device according to this embodiment will be described with reference to Figures 7 to 12. Figures 7 and 8 show the metal electrode layer formation process included in the solar cell manufacturing process in the method for manufacturing a solar cell device according to this embodiment, with Figure 8 being an enlarged view of part VIII in Figure 7. Figure 9 shows the conductive adhesive member coating process in the method for manufacturing a solar cell device according to this embodiment. Figures 10 and 11 show the inspection process in the method for manufacturing a solar cell device according to this embodiment, with Figure 11 being an enlarged view of part XI shown in Figure 10. Figure 12 shows the solar cell connection process included in the solar cell device formation process in the method for manufacturing a solar cell device according to this embodiment.

[0047] First, in each of the solar cells 2, a first conductivity type semiconductor layer 25 is formed on the light-receiving side of the semiconductor substrate 11, and a second conductivity type semiconductor layer 35 is formed on the back side of the semiconductor substrate 11. For example, CVD (chemical vapor deposition) or PVD (physical vapor deposition) can be used as the method for forming the first conductivity type semiconductor layer 25 and the second conductivity type semiconductor layer 35.

[0048] Next, in each of the solar cells 2, a first transparent electrode layer 28 is formed on the light-receiving side of the semiconductor substrate 11, and a second transparent electrode layer 38 is formed on the back side of the semiconductor substrate 11. For example, CVD (chemical vapor deposition) or PVD (physical vapor deposition) can be used to form the first transparent electrode layer 28 and the second transparent electrode layer 38.

[0049] Next, as shown in Figure 7, in each of the solar cells 2, a first metal electrode layer 29, i.e., finger electrode portion 29f and busbar electrode portion 29b, is formed on the light-receiving surface side of the semiconductor substrate 11, and a second metal electrode layer 39, i.e., finger electrode portion 39f and busbar electrode portion 39b, is formed on the back side of the semiconductor substrate 11 (metal electrode layer formation step). As a method for forming the first metal electrode layer 29 and the second metal electrode layer 39, for example, a printing method using silver paste, a dispenser method, or a coating method can be used.

[0050] In this case, as shown in Figures 7 and 8, an inspection area R1 in which the first busbar electrode portion is not formed is placed at at least one of the ends of the first busbar electrode portion 29b in the Y direction. Alternatively, an inspection area R2 in which the second busbar electrode portion is not formed is placed at at least one of the ends of the second busbar electrode portion 39b in the Y direction. In this way, multiple solar cells 2 are manufactured (solar cell manufacturing process).

[0051] Next, as shown in Figure 9, a conductive adhesive member 6 is applied to the first busbar electrode portion 29b of the first metal electrode layer 29 in each of the solar cells 2. Alternatively, a conductive adhesive member 6 is applied to the second busbar electrode portion 39b of the second metal electrode layer 39 in each of the solar cells 2 (conductive adhesive member application step). As a method for applying the conductive adhesive member 6, for example, screen printing using silver paste (CP) is used.

[0052] Next, as shown in Figure 10, the quality of the application of the conductive adhesive member 6 is inspected (inspection step). At this time, as shown in Figures 10 and 11, the quality of the application of the conductive adhesive member 6 is determined by the presence or absence of the conductive adhesive member 6 in the inspection area R1 or inspection area R2.

[0053] For example, inspection area R1 is approximately black because the first conductivity type semiconductor layer 25 and the first transparent electrode layer 28 are laminated on the light-receiving side of the semiconductor substrate 11. Similarly, inspection area R2 is approximately black because the second conductivity type semiconductor layer 35 and the second transparent electrode layer 38 are laminated on the back side of the semiconductor substrate 11.

[0054] This allows the presence or absence of silver paste in the conductive adhesive member 6 to be determined by the color tone (or brightness) of the inspection area R1 or inspection area R2. For example, the inspection area R1 or inspection area R2 is imaged by an imaging device 40 such as a camera and processed, and if the color tone (or brightness) of the inspection area R1 or inspection area R2 matches the color tone (or brightness) of the silver paste of the conductive adhesive member 6 that has been stored in advance, it is determined to be a good coated product. On the other hand, if the color tone (or brightness) of the inspection area R1 or inspection area R2 does not match the color tone (or brightness) of the silver paste of the conductive adhesive member 6, it is determined to be a defective coated product and is excluded.

[0055] Alternatively, the presence or absence of the conductive adhesive member 6 may be determined by the change in color (or brightness) of inspection area R1 or inspection area R2 before and after the conductive adhesive member coating process. For example, inspection area R1 or inspection area R2 is imaged using an imaging device 40 such as a camera and the image is processed. If the color (or brightness) of inspection area R1 or inspection area R2 changes from black to the color (or brightness) of the silver paste of the conductive adhesive member 6, it is determined to be a good coated product. On the other hand, if there is no or insufficient change in the color (or brightness) of inspection area R1 or inspection area R2 from black to the color (or brightness) of the silver paste of the conductive adhesive member 6, it is determined to be a defective coated product and is discarded.

[0056] Next, as shown in Figure 12, multiple coated, good quality solar cells 2 are connected using a single-ring method (solar cell connection process). In this way, a solar cell device 1 is manufactured (solar cell device manufacturing process).

[0057] Next, one or more solar cell devices 1 are sealed with a light-receiving protective member 3, a back-side protective member 4, and a sealing material 5 to obtain the solar cell module 100 shown in Figures 1 and 2.

[0058] As described above, the method for manufacturing a solar cell device according to this embodiment includes an inspection step to check the quality of the application of the conductive adhesive member 6 after the conductive adhesive member application step and before the solar cell device manufacturing step (i.e., the solar cell connection step). This makes it possible to eliminate defective products with poorly applied conductive adhesive members before the solar cell device manufacturing step, thereby suppressing the manufacture of unreliable solar cell devices and solar cell modules.

[0059] Furthermore, according to the solar cell 2 of this embodiment, an inspection area R1 is provided at least one of the Y-direction ends of the first busbar electrode portion 29b where the first busbar electrode portion 29b is not formed, or an inspection area R2 is provided at least one of the Y-direction ends of the second busbar electrode portion 39b where the second busbar electrode portion 39b is not formed. The inspection areas R1 and R2 are substantially black. As a result, according to the solar cell 2, solar cell device 1, and manufacturing method of the solar cell device of this embodiment, even if the color tones of the metal electrode layers 29 and 39 and the color tones of the conductive adhesive member 6 are similar, the quality of the coating of the conductive adhesive member 6 to the metal electrode layers 29 and 39 can be easily inspected by imaging with an imaging device 40 such as a camera and performing image processing.

[0060] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications and variations are possible. For example, in the embodiments described above, as shown in Figure 3, the inspection area R1 is located within the area at the end of the first busbar electrode portion 29b, or as shown in Figure 4, the inspection area R2 is located within the area at the end of the second busbar electrode portion 39b. However, the present invention is not limited thereto, and for example, as shown in Figures 13 and 14, the inspection area R1 may be located outside the area at the end of the first busbar electrode portion 29b (periphery), or the inspection area R2 may be located outside the area at the end of the second busbar electrode portion 39b (periphery).

[0061] Furthermore, the above-described embodiment illustrates a solar cell device 1 in which a plurality of double-sided electrode type solar cell cells 2 are connected using a single-ring method. However, the present invention is not limited to this and can also be applied to solar cell devices in which a plurality of back-contact type solar cell cells are connected using a single-ring method. [Explanation of symbols]

[0062] 1. Solar cell device (solar cell string) 2 solar cells 3. Light-receiving side protective member 4. Rear protective material 5. Sealing material 6. Conductive adhesive member 11 Semiconductor substrates 25 First Conductivity Semiconductor Layer 28 First transparent electrode layer 29 First metal electrode layer (first metal electrode) 29f First finger electrode section 29b First busbar electrode section (first busbar electrode) 35 Second Conductivity Semiconductor Layer 38 Second transparent electrode layer 39 Second metal electrode layer (second metal electrode) 39f Second finger electrode section 39b Second busbar electrode section (second busbar electrode) 40 Imaging device 100 solar modules Ro superposition region R1, R2 Examination Area

Claims

1. A solar cell comprising a first metal electrode formed on one main surface side of a semiconductor substrate and a second metal electrode formed on the other main surface side of the semiconductor substrate, The first metal electrode includes a first busbar electrode at one end in the first direction, which extends in a second direction intersecting the first direction. The second metal electrode includes a second busbar electrode extending in the second direction at the other end in the first direction, At least one side of the end of the first busbar electrode or the second busbar electrode in the second direction is provided with an inspection area for inspecting the quality of the application of the conductive adhesive member, the inspection area in which the first busbar electrode or the second busbar electrode is not formed. Solar cell.

2. The solar cell according to claim 1, wherein the inspection area is located at both ends of the first busbar electrode.

3. The solar cell according to claim 1, wherein the inspection area is located within the area of ​​the end of the first busbar electrode.

4. In the region of the first busbar electrode or the second busbar electrode, the transparent electrode layer and the first metal electrode are stacked in order from the semiconductor substrate side. In the aforementioned inspection area, a transparent electrode layer is stacked and exposed. The solar cell according to claim 1.

5. The area of ​​the inspection region is 0.5 mm². ２ The solar cell according to claim 1, wherein the following:

6. A plurality of solar cells according to any one of claims 1 to 5, Conductive adhesive member and Equipped with, The plurality of solar cells are arranged in the first direction, and are connected with some of their ends overlapping using a single-ring method. The first busbar electrode of one of the adjacent solar cells in the plurality of solar cells is connected to the second busbar electrode of the other adjacent solar cell via the conductive adhesive member. Solar cell devices.

7. A solar cell manufacturing process for manufacturing a plurality of solar cells, comprising a metal electrode layer formation step of forming a first metal electrode on one main surface side of a semiconductor substrate and a second metal electrode on the other main surface side of the semiconductor substrate, wherein the first metal electrode includes a first busbar electrode extending in a second direction intersecting the first direction at one end in the first direction, and the second metal electrode includes a second busbar electrode extending in the second direction at the other end in the first direction. A conductive adhesive member application step of applying a conductive adhesive member to the first busbar electrode or the second busbar electrode in each of the plurality of solar cells, An inspection step for inspecting the quality of the application of the conductive adhesive member, A solar cell device manufacturing process includes a solar cell connection process in which multiple good solar cells obtained through the inspection process are connected using a single-ring method, and a solar cell device manufacturing process is performed to manufacture a solar cell device. Includes, In the metal electrode formation process, an inspection area for inspecting the quality of the formation of the conductive adhesive member is placed on at least one side of the end of the first busbar electrode or the second busbar electrode in the second direction, where the first busbar electrode or the second busbar electrode is not formed. In the inspection step, the quality of the application of the conductive adhesive member is determined based on the presence or absence of the conductive adhesive member in the inspection area. A method for manufacturing solar cell devices.

8. The method for manufacturing a solar cell device according to claim 7, wherein the presence or absence of the conductive adhesive member in the inspection area is determined by the color tone of the inspection area in the inspection step.

9. The method for manufacturing a solar cell device according to claim 7, wherein the inspection step determines the presence or absence of the conductive adhesive member in the inspection area by the change in the color tone of the inspection area before and after the conductive adhesive member coating step.

10. The material of the first metal electrode and the second metal electrode is silver paste. The material of the conductive adhesive member is silver paste. A method for manufacturing a solar cell device according to any one of claims 7 to 9.

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