Solar cell module

Abstract

To improve the fire resistance of solar cell modules. [Solution] The solar cell module comprises a light-transmitting resin surface protective layer, a first fiber layer in which a first impregnating material is impregnated into a first fiber material, a solar cell element disposed between the surface protective layer and the first fiber layer, a support member disposed between the surface protective layer and the first fiber layer, and a filler that fills the space between the surface protective layer and the first fiber layer, covering the solar cell element and the support member. The support member overlaps with the first fiber layer in a plan view, but does not overlap with the solar cell element in a plan view.

Description

Technical Field

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

Background Art

[0002] There is a demand for weight reduction of solar cell modules. For example, in Patent Document 1, a resin protection layer is disposed on the light-receiving surface side of a solar cell instead of a glass protection layer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is room for improvement from the viewpoint of enhancing the fire resistance in a solar cell module.

Means for Solving the Problems

[0005] A solar cell module according to a first aspect of the technology disclosed in the present specification includes a resin surface protection layer having translucency, a first fiber layer in a state where a first impregnating material is impregnated in a first fiber material, a solar cell element disposed between the surface protection layer and the first fiber layer, a support member disposed between the surface protection layer and the first fiber layer, and a filler filled between the surface protection layer and the first fiber layer so as to cover the solar cell element and the support member. The support member overlaps with the first fiber layer in a plan view and does not overlap with the solar cell element in a plan view.

Effects of the Invention

[0006] The fire resistance in a solar cell module can be enhanced.

Brief Description of the Drawings

[0007] [Figure 1] This is a plan view showing an example of the appearance of a solar cell module according to the first embodiment when viewed from above. [Figure 2] This figure shows an example of a hypothetical cross-section along the Ib-Ib line of the solar cell module shown in Figure 1. [Figure 3] This figure shows an example of the structure of a solar cell element when viewed from above, specifically the first element surface. [Figure 4] This figure shows an example of the structure of a solar cell element when viewed from above, specifically the second element surface. [Figure 5] This figure shows an example of how the solar cell module shown in Figure 1 is attached to the mounting component. [Figure 6] This figure illustrates the state of a cross-section during the manufacturing process of a solar cell module according to the first embodiment. [Figure 7] This figure illustrates the state of a cross-section during the manufacturing process of a solar cell module according to the first embodiment. [Figure 8] This figure illustrates the state of a cross-section during the manufacturing process of a solar cell module according to the first embodiment. [Figure 9] This is a cross-sectional view showing an example of a laminated structure near a support member. [Figure 10] This is a cross-sectional view showing an example of a laminated structure near a support member. [Figure 11] This is a cross-sectional view showing an example of a laminated structure near the support member according to the second embodiment. [Figure 12] This is a cross-sectional view showing an example of a laminated structure near a support member according to the third embodiment. [Figure 13] This is a cross-sectional view showing an example of a laminated structure near a support member according to the fourth embodiment. [Figure 14] This is a magnified diagram illustrating a schematic example of the gaps in the fibrous material used in the fiber layer. [Figure 15] This figure shows an example of the relationship between the void ratio of fibrous material and the burn time of the fibrous layer. [Modes for carrying out the invention]

[0008] For the purpose of reducing the weight of a solar cell module, a resin protective layer is disposed on the light-receiving surface side of a solar cell instead of a glass protective layer.

[0009] By the way, the resin protective layer has lower fire resistance than the glass protective layer. Therefore, when the solar cell module becomes high temperature due to a fire or the like, there is concern that the filling material covering the solar cell element melts and flows downward.

[0010] Therefore, the inventor of the present disclosure has created a technology capable of enhancing the fire resistance of a solar cell module. Regarding this, the first to fourth embodiments will be described below based on the drawings.

[0011] In the drawings, parts having the same or similar configurations and functions are denoted by the same reference numerals, and redundant descriptions are omitted in the following description. The drawings are schematically shown. In FIGS. 1 to 14, a right-handed XYZ coordinate system is attached. In this XYZ coordinate system, the short-side direction of the front surface 10f of the solar cell panel 10 is taken as the +X direction, the long-side direction of the front surface 10f is taken as the +Y direction, and the normal direction of the front surface 10f orthogonal to both the +X direction and the +Y direction is taken as the +Z direction.

[0012] Also, in the present disclosure, even when ordinal numbers such as "first" or "second" are used, these terms are used for convenience in order to facilitate understanding of the contents of the embodiments, and the contents of the embodiments are not limited to the order or the like that may be caused by these ordinal numbers in any way.

[0013] Also, in the present disclosure, when it is described as "A or B", this description shall include, as long as there is no contradiction, the case where only one of A and B is shown and the case where both A and B are shown.

[0014] <First Embodiment> Hereinafter, the solar cell module according to the present embodiment will be described.

[0015] <Solar modules> Figure 1 is a plan view showing an example of the appearance of a solar cell module according to the first embodiment when viewed from above. Here, a plan view corresponds to viewing the solar cell module toward its main surface. Figure 2 is a diagram showing an example of a hypothetical cross-section along the Ib-Ib line of the solar cell module in Figure 1. The region RA shown in Figure 2 will be described later.

[0016] As shown in Figures 1 and 2, the solar cell module 100 includes, for example, a solar cell panel 10. The solar cell panel 10 has, for example, a light-receiving surface (also called the front surface 10f) to which light is mainly incident, and a back surface 10b located on the opposite side of the front surface 10f. In the first embodiment, the front surface 10f is facing in the +Z direction, and the back surface 10b is facing in the -Z direction. The +Z direction is set, for example, to face the sun at its highest point in the sky. In the example of Figure 1, the front surface 10f has a rectangular shape as an example of a square shape.

[0017] The solar cell module 100 may further include a terminal box (not shown) for extracting the power generated by the solar cell panel 10 to the outside.

[0018] As shown in Figures 1 and 2, the solar cell panel 10 comprises, for example, a surface protective layer 1, a solar cell portion 3, a filler 4, a support member 5, a fiber layer 6, and an adhesive layer 7. The solar cell panel 10 may also have a back surface protective layer 2. Furthermore, the solar cell panel 10 may be provided with mounting holes 11 for inserting, screwing in, or hooking a fixing device 111 when attaching the solar cell panel 10 to a mounting target such as a roof.

[0019] <Surface protective layer> The surface protection layer 1 has, for example, a first surface 1f and a second surface 1s (see Figure 2). In the first embodiment, the first surface 1f constitutes, for example, the front surface 10f of the solar cell panel 10. That is, the surface protection layer 1 has a rectangular shape as an example of a square shape. The corners of the rectangular surface protection layer 1 may be chamfered as appropriate. In the examples of Figures 1 and 2, the first surface 1f is exposed to the space outside the solar cell module 100 (also referred to as the external space 200). The second surface 1s is the surface opposite to the first surface 1f.

[0020] The surface protective layer 1 has, for example, light transmittance. Specifically, the surface protective layer 1 has, for example, light transmittance to light within a specific range of wavelengths. The specific range of wavelengths includes, for example, the wavelengths of light that the solar cell unit 3 can photoelectrically convert. If the specific range of wavelengths includes wavelengths of light with high irradiation intensity from sunlight, the photoelectric conversion efficiency of the solar cell module 100 can be improved.

[0021] The material of the surface protection layer 1 is, for example, a weather-resistant resin. In other words, the surface protection layer 1 is a layer made of, for example, a weather-resistant resin. Here, weather resistance means the property of being resistant to deterioration such as deformation, discoloration, and degradation when used outdoors. By applying resin to the material of the surface protection layer 1, the surface protection layer 1 reduces the intrusion of water, such as water droplets, from the external space 200 of the solar cell module 100 toward the solar cell section 3, and also has the property of allowing moisture to pass easily from the filler material 4 toward the external space 200 (also called moisture permeability and waterproofing). Here, the weather-resistant resin includes, for example, polyethylene terephthalate (PET) or a fluorine-based resin. Fluorine-based resins include, for example, fluorinated ethylene propylene copolymer (FEP), ethylene tetrafluoroethylene copolymer (ETFE), and ethylene chlorotrifluoroethylene copolymer (ECTFE). Here, for example, the surface protective layer 1 may be composed of two or more weather-resistant resins. In this case, the resin applied to the surface protective layer 1 may be, for example, two or more types of resins. For this reason, for example, an embodiment in which the resin applied to the surface protective layer 1 includes at least one resin from among PET, FEP, ETFE, and ECTFE is conceivable.

[0022] The thickness of the surface protection layer 1 is, for example, about 0.01 millimeters (mm) to 0.5 mm. Thus, the surface protection layer 1 is made of a relatively low-density resin that is permeable to moisture, and because it is thin, the surface protection layer 1 is lightweight. For this reason, compared to a structure in which a high-density glass with a thickness of about 1 mm or more is used instead of the surface protection layer 1, the solar cell module 100 can be made lighter and the solar cell module 100 can be made thinner.

[0023] In addition, the material of the surface protection layer 1 may be acrylic resin and polycarbonate, or other resins, instead of the resin mentioned above, or in combination with the resin mentioned above. When acrylic resin and polycarbonate are used, the thickness of the resin is, for example, about 0.03 mm to 0.6 mm. The surface protection layer 1 may be composed of multiple types of resins laminated together.

[0024] The surface protection layer 1 may be, for example, a layer that reduces the transmission of light (ultraviolet light) with a wavelength of 360 nm or less by 10% or less. In this case, the surface protection layer 1 contains an ultraviolet absorber that reduces the transmission of light (ultraviolet light) with a wavelength of 360 nm or less by 10% or less. Examples of ultraviolet absorbers include salicylic acid-based, benzophenone-based, benzotriazole-based, cyanoacrylate-based, and triazine-based organic compounds.

[0025] Furthermore, if the surface protection layer 1 has a laminated structure consisting of multiple layers, the above-mentioned ultraviolet absorber may be included in the adhesive portion (not shown here) that bonds each of the layers constituting the surface protection layer 1. Even when the ultraviolet absorber is included in the adhesive portion, the amount of ultraviolet light transmitted through the surface protection layer 1 can be reduced to 10% or less. Examples of adhesive portions include ethylene vinyl acetate copolymer (EVA), polyolefin elastomer (POE), and acrylic adhesives.

[0026] <Solar cell department> The solar cell section 3 is located, for example, between the surface protection layer 1 and the back protection layer 2. In other words, the solar cell section 3 is facing the surface protection layer 1 in the Z direction and also facing the back protection layer 2 in the Z direction. Alternatively, the solar cell section 3 is located, for example, between the surface protection layer 1 and the fiber layer 6. In other words, the solar cell section 3 is facing the surface protection layer 1 in the Z direction and also facing the fiber layer 6 in the Z direction. The solar cell section 3 has at least one solar cell element 31. In the example shown in Figures 1 and 2, the solar cell section 3 has a plurality of solar cell elements 31. The plurality of solar cell elements 31 are located between the second surface 1s of the surface protection layer 1 and the back protection layer 2. In the first embodiment, the plurality of solar cell elements 31 are arranged in a two-dimensional manner. In the example shown in Figures 1 and 2, the plurality of solar cell elements 31 are arranged planarly so as to be located along the second surface 1s of the surface protection layer 1. Note that the plurality of solar cell elements 31 may be arranged in a one-dimensional manner.

[0027] The solar cell unit 3 further includes, for example, a plurality of first wiring materials 32, a second wiring material 33, and a third wiring material 34. The solar cell unit 3 includes, for example, a plurality (here, two) solar cell strings 30. The plurality of solar cell strings 30 are arranged, for example, in the X direction. Each of the plurality of solar cell strings 30 includes, for example, a plurality (here, six) solar cell elements 31 and a plurality of first wiring materials 32. In each solar cell string 30, the plurality of solar cell elements 31 are arranged, for example, in the Y direction. The plurality of first wiring materials 32 are in a state where, for example, two adjacent solar cell elements 31 among the plurality of solar cell elements 31 are electrically connected. The second wiring material 33 is in a state where two adjacent solar cell strings 30 among the plurality of solar cell strings 30 are electrically connected. In the example of Figures 1 and 2, the two third wiring materials 34 are each connected to two solar cell strings 30. The third wiring material 34 connected to the solar cell string 30 located at the furthest -X direction end, and the third wiring material 34 connected to the solar cell string 30 located at the furthest +X direction end, are both extended to the outside of the solar cell panel 10.

[0028] Each of the multiple solar cell elements 31 can convert light energy into electrical energy. Each of the multiple solar cell elements 31 has a surface located on the front side (also called the first element surface 31f) and a surface on the opposite side of the first element surface 31f (also called the second element surface 31s). In the example in Figure 2, the first element surface 31f is facing in the +Z direction, and the second element surface 31s is facing in the -Z direction. In this case, for example, the first element surface 31f mainly acts as the surface to which light is incident (also called the light-receiving surface), and the second element surface 31s mainly acts as the surface to which light is not incident (also called the back surface).

[0029] In the first embodiment, as shown in Figures 3 and 4, each of the plurality of solar cell elements 31 includes a semiconductor substrate 310, a first output electrode 311, a first current collector electrode 312, a second output electrode 313, and a second current collector electrode 314. Here, Figure 3 is a diagram showing an example of the structure when the first element surface of the solar cell element is viewed from above. Figure 4 is a diagram showing an example of the structure when the second element surface of the solar cell element is viewed from above.

[0030] The semiconductor substrate 310 can be made of, for example, crystalline semiconductors such as crystalline silicon, amorphous semiconductors such as amorphous silicon, or compound semiconductors using four elements such as copper, indium, gallium, and selenium, or two elements such as cadmium and tellurium. Here, we assume that crystalline silicon is used for the semiconductor substrate 310. The Young's modulus of crystalline silicon is 160 GPa, and the coefficient of linear expansion is 4 × 10⁻⁶. -6 The coefficient of conductivity is / K. In this case, the semiconductor substrate 310 mainly has a region having a first conductivity type (also called the first conductivity type region) and a region having a second conductivity type opposite to the first conductivity type (also called the second conductivity type region). The first conductivity type region is located, for example, on the second element surface 31s side in the -Z direction of the semiconductor substrate 310. The second conductivity type region is located, for example, on the surface layer side of the first element surface 31f side in the +Z direction of the semiconductor substrate 310. Here, for example, if the first conductivity type is p type, the second conductivity type will be n type. Also, for example, if the first conductivity type is n type, the second conductivity type will be p type. As a result, the semiconductor substrate 310 has a pn junction located at the interface between the first conductivity type region and the second conductivity type region. The thickness of the semiconductor substrate 310 is, for example, about 0.15 mm to 0.5 mm.

[0031] The first output electrodes 311 and the first current collector electrodes 312 are located, for example, on the surface of the semiconductor substrate 310 on the first element surface 31f side. For example, a busbar electrode is applied to the first output electrodes 311. For example, a finger electrode is applied to the first current collector electrodes 312. In the example of Figure 3, five substantially parallel first output electrodes 311 are located on the first element surface 31f side of the semiconductor substrate 310, and a number of substantially parallel first current collector electrodes 312 are located substantially perpendicular to the five first output electrodes 311. In the example of Figure 3, each of the first output electrodes 311 has an elongated shape that is long in the Y direction, and each of the first current collector electrodes 312 has a linear shape that is long in the X direction. Furthermore, in the region of the semiconductor substrate 310 where the first output electrode 311 and the first current collector electrode 312 are not formed, an insulating film as an anti-reflective film 315, for example, made of silicon nitride, may be located. Here, for example, if the main component of the first output electrode 311 is silver, the first output electrode 311 can be formed by applying silver paste to a desired shape using screen printing or the like, and then firing it. The main component refers to the component that has the largest (highest) proportion (also called the content rate) among the contained components. For example, the silver paste can be a metal paste containing silver as the main component, an organic vehicle, and glass frit. For example, if the main component of the first current collector electrode 312 is silver, the first current collector electrode 312 can be formed by applying silver paste to a desired shape using screen printing or the like, and then firing it. The first output electrode 311 and the first current collector electrode 312 may be formed in separate processes or in the same process.

[0032] The second output electrode 313 and the second current collector electrode 314 are located, for example, on the second element surface 31s side of the semiconductor substrate 310. For example, a busbar electrode is applied to the second output electrode 313. In the example of Figure 4, five rows of second output electrodes 313 are located on the second element surface 31s side of the semiconductor substrate 310, substantially parallel to each other along the +Y direction. The second current collector electrode 314 is located on the second element surface 31s side of the semiconductor substrate 310, covering substantially the entire area where the second output electrodes 313 are not formed, except for the portion where the second output electrodes 313 and the second current collector electrode 314 are connected by overlapping. Each of the five rows of second output electrodes 313 includes, for example, four electrodes arranged in a row. Furthermore, for example, a thin film of an oxide or nitride such as aluminum oxide may exist as a passivation film in a desired pattern between the first conductivity type region of the semiconductor substrate 310 and the second output electrode 313 and the second current collector electrode 314. Here, for example, if the main component of the second output electrode 313 is silver, the second output electrode 313 can be formed by applying silver paste in a desired shape by screen printing or the like and then firing it. For example, if the main component of the second current collector electrode 314 is aluminum, the second current collector electrode 314 can be formed by applying aluminum paste in a desired shape by screen printing or the like and then firing it. For example, the aluminum paste may be a metal paste containing metal powder with aluminum as the main component, an organic vehicle and glass frit.

[0033] The first wiring material 32 is electrically connected, for example, to the first output electrode 311 of one solar cell element 31 and to the second output electrode 313 of another solar cell element 31 adjacent to this first solar cell element 31. In the examples of Figures 3 and 4, the outer edges of the multiple first wiring materials 32 attached to each of the solar cell elements 31 are virtually depicted by dashed lines. In the examples of Figures 1 to 4, the first wiring material 32 has an elongated shape that is long in the Y direction. Here, the first wiring material 32 is joined to, for example, the first output electrode 311 and the second output electrode 313. Specifically, for example, there is a portion (also called the first joining portion 321) located between the first wiring material 32 and the first output electrode 311 that joins the first wiring material 32 and the first output electrode 311. Therefore, for example, the first wiring material 32 is joined to the first output electrode 311 of one solar cell element 31 via the first junction portion 321. Also, for example, there is a portion (also called the second junction portion 322) located between the first wiring material 32 and the second output electrode 313 that joins the first wiring material 32 and the second output electrode 313. Therefore, for example, the first wiring material 32 is joined to the second output electrode 313 of another solar cell element 31 adjacent to one solar cell element 31 via the second junction portion 322. For example, a linear or strip-shaped conductive metal body is applied to the first wiring material 32. For example, the material of the first junction portion 321 and the second junction portion 322 is an alloy with a low melting point such as solder or a single metal with a low melting point. More specifically, for example, a copper foil having a thickness of about 0.1 mm to 0.2 mm and a width of about 1 mm to 2 mm is applied to the first wiring material 32, and the entire surface of the first wiring material 32 is covered with solder. The first wiring material 32 is electrically connected to the first output electrode 311 and the second output electrode 313, for example, by soldering. In this case, for example, the solder located between the first wiring material 32 and the first output electrode 311 constitutes the first joint portion 321. Also, for example, the solder located between the first wiring material 32 and the second output electrode 313 constitutes the second joint portion 322.

[0034] <Filling material> The filler material 4 covers the solar cell section 3 and the support member 5 between the surface protective layer 1 and the back protective layer 2. In other words, the filler material 4 covers multiple solar cell elements 31 and the support member 5 between the surface protective layer 1 and the back protective layer 2.

[0035] The filler material 4 has a first surface 4f located on the front side and a second surface 4s located on the opposite side from the first surface 4f. The first surface 4f of the filler material 4 is in contact with the second surface 1s of the surface protective layer 1, and the second surface 4s of the filler material 4 is in contact with the fiber layer 6.

[0036] In the first embodiment, the filler 4 includes, for example, a filler located on the front surface 10f side (also referred to as the first filler 41) and a filler located on the back surface 10b side (also referred to as the second filler 42). The first filler 41 is, for example, in a state that constitutes the first surface 4f and covers the entire surface of the solar cell section 3 on the surface protection layer 1 side. In other words, the first filler 41 is, for example, in a state that covers the multiple solar cell elements 31 between the surface protection layer 1 and the multiple solar cell elements 31. The second filler 42 is, for example, in a state that constitutes the second surface 4s and covers the entire back surface of the solar cell section 3 on the back protection layer 2 side. In other words, the second filler 42 is, for example, in a state that covers the multiple solar cell elements 31 between the back protection layer 2 and the multiple solar cell elements 31. Therefore, in the first embodiment, the solar cell section 3 is, for example, surrounded by being sandwiched between the first filler 41 and the second filler 42. This allows, for example, the orientation of the solar cell section 3 to be maintained by the filler material 4.

[0037] Furthermore, the filler 4 has, for example, light-transmitting properties. Here, the filler 4 has, for example, light-transmitting properties to light of a specific range of wavelengths as described above. Here, for example, if at least the first filler 41 of the first filler 41 and second filler 42 constituting the filler 4 has light-transmitting properties, incident light from the front surface 10f can reach the solar cell section 3.

[0038] The material for the first filler 41 can be, for example, ionomer (IO), ethylene vinyl acetate copolymer (EVA), polyolefin elastomer (POE), polyvinyl butyral (PVB), polyvinyl acetal, or acid-modified resin. Here, IO is a thermoplastic resin formed by introducing a small amount of ionic groups into the backbone of low-density polyethylene as a host polymer, thereby crosslinking some of the molecules. As ionic groups, metal ions such as sodium ions, zinc ions, potassium ions, and magnesium ions can be used. The ionic groups form ionic aggregates and act as pseudocrosslinking points, thereby imparting various physical properties to the host polymer. Such IO has, for example, high melt tension, melt viscosity, and transparency.

[0039] When the first filler 41 is IO, the combustion reaction temperature is approximately 400°C, and the thermal conductivity is 0.3 W / mK or higher and 0.4 W / mK or lower. Here, the combustion reaction temperature refers to the temperature at which the combustion reaction occurs (ignition temperature), as measured by differential thermal-thermogravimetric analysis (TG-DTA), etc.

[0040] Furthermore, if, for example, relatively inexpensive EVA is used as the material for the first filler 41, the ability to protect multiple solar cell elements 31 can be easily achieved. For the acid-modified resin, for example, a modified polyolefin resin that can be formed by graft modification with an acid on a resin such as polyolefin can be used. Acids that can be used for graft modification of the acid-modified resin include, for example, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, maleic anhydride, hymic anhydride, itaconic anhydride, and citraconic anhydride. For the material of the second filler 42, for example, polyvinyl acetal such as IO, EVA, POE, and PVB, and acid-modified resins can be used. The first filler 41 and the second filler 42 may be composed of, for example, two or more types of materials.

[0041] The second filler 42 may contain, for example, a pigment. If, for example, a white pigment is included, the light transmitted through the solar cell section 3 can be reflected by the second filler 42 and re-entered into the solar cell section 3. This can improve the power generation efficiency of the solar cell module 100.

[0042] Note that the filler 4 may not have a second filler 42, and may only have the first filler 41. In this case, the first filler 41 covers the solar cell portion 3 between the surface protective layer 1 and the back protective layer 2.

[0043] <Fiber layer> The fiber layer 6 is a layer formed, for example, by impregnating at least a portion of the gaps between the fibers with an impregnating material. The fiber layer 6 has, for example, a first surface 6f and a second surface 6s located on the opposite side of the first surface 6f (see Figure 2). The first surface 6f of the fiber layer 6 is, for example, facing the second surface 1s of the surface protection layer 1. The fiber layer 6 is in contact with the filler 4 on the side opposite to the surface protection layer 1. The fiber layer 6 is positioned facing the solar cell section 3 and the support member 5 in the Z direction.

[0044] The fiber layer 6 shown in Figure 2 is positioned to overlap the entire solar cell element 31 in a plan view. However, the fiber layer 6 may overlap only a portion of the solar cell element 31, or it may be positioned to surround the solar cell element 31 in a plan view, excluding only the portion that overlaps with the solar cell element 31. When the fiber layer 6 is positioned to surround the solar cell element 31 in a plan view, it is possible to reduce the area on which the fiber layer 6 is formed while hindering air movement in the region that does not overlap with the solar cell element in a plan view, thereby contributing to improved fire resistance of the solar cell module.

[0045] The thickness of the fiber layer 6 is, for example, about 0.01 mm to 0.5 mm. The fiber material included in the fiber layer 6 is, for example, a non-combustible or flame-retardant material such as glass fiber or metal fiber. The impregnating material used to impregnate the fiber material is, for example, IO, epoxy resin, EVA, POE, or polymethyl methacrylate resin. When the fiber material is glass fiber, the softening point of the fiber material is about 844°C. The thermal conductivity of the glass constituting the glass fiber is 1.0 W / mK, and when the impregnating material is the same IO as the filler 4, the thermal conductivity of IO is 0.3 W / mK or higher and 0.4 W / mK or lower. For this reason, the thermal conductivity of the fiber layer 6, which is a composite material of glass fiber and impregnating material, is considered to be higher than that of the filler 4.

[0046] Figure 14 is a schematic enlarged view showing an example of the gaps between the fibrous material used in the fiber layer 6. In Figure 14, the fibrous material 61 in the fiber layer 6 is shown in a plan view, woven together in a plain weave pattern.

[0047] Figure 14 shows gaps 62 where no fiber material 61 is present. Here, the gap ratio is defined as the ratio of the area of ​​gaps 62 to the area of ​​fiber material 61 per unit area. The gaps 62 used in calculating the gap ratio correspond to the regions where no fiber material 61 exists when viewed in plan view, in other words, along the Z-axis. In the case shown in Figure 14, the fiber material 61 is plain woven, but if the fiber material 61 has a structure in the Z-axis direction as well, such as a nonwoven fabric, in other words, it may have a three-dimensional structure. In such cases, the gaps 62 correspond to the regions where none of the fiber material 61 that extends in the Z-axis direction are present when viewed in plan view.

[0048] Figure 15 shows an example of the relationship between the void ratio of the fiber material and the burn-through time of the fiber layer. In Figure 15, the vertical axis represents the burn-through time (the numerical value is a relative value), and the horizontal axis represents the void ratio [%]. Here, the burn-through time of the fiber layer refers to the time it takes for the resin adjacent to the fiber layer (for example, the resin located on the light-receiving surface side of the fiber layer) to burn when the impregnating material melts and becomes fluid due to heating, forming through holes that promote oxygen supply.

[0049] In Figure 15, a burn-through time of 30 is set as the fire resistance threshold of 400. This threshold of 400 is set as a value that indicates the ability to withstand a predetermined time without burning through in a flame propagation test, and represents fire resistance equivalent to fire safety class C in the JIS fire test method for photovoltaic (PV) modules.

[0050] As shown in Figure 15, when an approximation curve 402 is generated using the distribution of burn-through time for fiber materials with a gap ratio of 0%, in other words, fiber materials with no gaps, the distribution of burn-through time for fiber materials with a gap ratio of 3.3%, the distribution of burn-through time for fiber materials with a gap ratio of 24.3%, and the distribution of burn-through time for fiber materials with a gap ratio of 100%, in other words, the gap ratio at the intersection of the approximation curve 402 and the threshold 400 is 64%.

[0051] From the above, it can be said that when the gap ratio of the fiber material 61 is 64% or less, the fiber layer 6 improves the fire resistance of the solar cell module 100. Furthermore, when the gap ratio of the fiber material 61 is 24.3% or less, the fiber layer 6 further improves the fire resistance of the solar cell module 100. Furthermore, when the gap ratio of the fiber material 61 is 3.3% or less, the fiber layer 6 further improves the fire resistance of the solar cell module 100.

[0052] <Adhesive layer> The adhesive layer 7 is, for example, a layer that adheres the fiber layer 6 and the back protective layer 2. The adhesive layer 7 has, for example, a first surface 7f and a second surface 7s located on the opposite side of the first surface 7f (see Figure 2). The first surface 7f of the adhesive layer 7 is, for example, adhered to the second surface 6s of the fiber layer 6.

[0053] The thickness of the adhesive layer 7 is, for example, about 0.1 mm to 0.5 mm. The material constituting the adhesive layer 7 may be, for example, IO, EVA, or POE. The adhesive layer 7 may also be made of the same material as the filler 4.

[0054] <Back protective layer> The back protective layer 2 is, for example, in a state where it constitutes the back surface 10b of the solar cell panel 10. The back protective layer 2 is bonded to the fiber layer 6 via the adhesive layer 7. The back protective layer 2 has, for example, a first surface 2f and a second surface 2s located on the opposite side of the first surface 2f (see Figure 2).

[0055] The back protective layer 2 can, for example, protect the solar cell portion 3 from the back surface 10b side. For example, a backsheet constituting the back surface 10b is applied to the back protective layer 2. The thickness of the backsheet is, for example, about 0.15 mm to 0.5 mm.

[0056] For example, resin can be used as the material for the backsheet. The resin can be, for example, the same material as the surface protective layer 1. When viewed from the back surface 10b side, the back protective layer 2 has the same or a similar shape as the surface protective layer 1. For example, when viewed from the back surface 10b side, both the surface protective layer 1 and the back protective layer 2 are assumed to have a rectangular outer shape. The corners of the rectangular back protective layer 2 may be chamfered as appropriate.

[0057] The distance between the surface protective layer 1 and the back protective layer 2 increases in the area where the support member 5 is placed. More specifically, the fiber layer 6, adhesive layer 7, and back protective layer 2 are arranged such that the distance from the surface protective layer 1 increases as they approach the support member 5.

[0058] Furthermore, if either the material of the back protective layer 2 or the material of the fiber layer 6 is a material that can be fused to an adjacent layer by heating during the lamination process described later, the adhesive layer 7 may not be provided.

[0059] <Support member> The support member 5 is a component for improving the rigidity of the solar cell panel 10, and has higher rigidity than, for example, the combined rigidity of the surface protective layer 1, the back protective layer 2, and the filler material 4. The material of the support member 5 can be, for example, metal, and more specifically, aluminum or stainless steel can be used. The support member 5 has, for example, a first surface 5f and a second surface 5s located on the opposite side of the first surface 5f (see Figure 2).

[0060] In a plan view, the support member 5 is positioned adjacent to the solar cell section 3 with a gap between them. In other words, in a plan view, the support member 5 is positioned so as not to overlap with the solar cell element 31. The support member 5 is positioned between the surface protective layer 1 and the back protective layer 2, covered by the filler material 4. In other words, the support member 5 is facing the surface protective layer 1 in the Z direction, and also facing the back protective layer 2 in the Z direction, and is covered by the filler material 4. Furthermore, the support member 5 is positioned between the surface protective layer 1 and the fiber layer 6, covered by the filler material 4. In other words, the support member 5 is facing the surface protective layer 1 in the Z direction, and also facing the fiber layer 6 in the Z direction (i.e., overlapping in a plan view), and is covered by the filler material 4.

[0061] In the examples of Figures 1 and 2, the support member 5 has a plate-like shape and a rectangular shape in plan view. In the example of Figure 2, the ZX cross-section of the support member 5 also has a rectangular shape. The corners of the support member 5 may be chamfered as appropriate. The longitudinal direction of the support member 5 (here, the Y direction) is, for example, along one side of the surface protective layer 1. Also, the longitudinal direction of the support member 5 is, for example, along the arrangement direction (here, the Y direction) of the multiple solar cell elements 31 included in one solar cell string 30. In other words, the longitudinal direction of the support member 5 is, for example, along the longitudinal direction (here, the Y direction) of the first wiring material 32.

[0062] In the examples shown in Figures 1 and 2, the solar cell panel 10 includes two support members 5. The two support members 5 are positioned along both sides of the surface protection layer 1 in the X direction. The sides located on both sides in the X direction include one side of the surface protection layer 1 that extends along the Y direction at the -X direction end and one side that extends along the Y direction at the +X direction end. In other words, one support member 5 is located at the -X direction end of the surface protection layer 1 and has a rectangular shape with its longitudinal direction being the Y direction, while the other support member 5 is located at the +X direction end of the surface protection layer 1 and has a rectangular shape with its longitudinal direction being the Y direction. The length of the support member 5 in the longitudinal direction (here, the Y direction) is approximately equal to the length of the surface protection layer 1, for example. However, the support member 5 may extend along the entire side of the surface protection layer 1, or it may be positioned partially (for example, intermittently) along the side of the surface protection layer 1. The width of the support member 5 in the shorter direction (in this case, the X direction) is set to, for example, several tens of millimeters or more. The thickness of the support member 5 is greater than the thickness of the solar cell part 3, and is set to, for example, about 1 mm to 5 mm.

[0063] Figure 5 shows an example of how the solar cell module shown in Figure 1 is attached to the mounting component. In the view shown in Figure 5, in addition to the configuration shown in the view shown in Figure 2, mounting holes 11 are shown on the solar cell module. The region RB shown in Figure 5 will be described later.

[0064] The mounting hole 11 is formed extending from the first surface 1f of the surface protective layer 1 to the second surface 2s of the back protective layer 2. In other words, the mounting hole 11 is a hole that connects the surface protective layer 1, the filler 4, the support member 5, the fiber layer 6, the adhesive layer 7, and the back protective layer 2.

[0065] When attaching the solar cell module 100 to a mounting target such as a roof, a fixing device 111 is inserted into the mounting hole 11. The fixing device 111 shown in Figure 5 has a pin portion 111a facing the mounting hole 11 from the +Z direction side and a base portion 111b facing the mounting hole 11 from the -Z direction side. In this case, by inserting the pin portion 111a into the mounting hole 11 from the +Z direction side and making contact with the base portion 111b from the -Z direction side of the mounting hole 11, the solar cell module 100 is fixed by being sandwiched from both sides in the Z direction at the location of the mounting hole 11.

[0066] Furthermore, the method of fixing the fixing device 111 to the mounting hole 11 is not limited to the method shown in Figure 5, i.e., insertion of the pin portion. For example, a bolt or the like may be screwed into a screw groove formed in the mounting hole 11, or a part of the fixing device may be caught on the upper part of the mounting hole 11 to fix the solar cell module 100.

[0067] <Manufacturing method for solar cell modules> Next, an example of a method for manufacturing the solar cell module 100 will be described based on Figures 6 to 8. Here, Figures 6 to 8 are diagrams illustrating the cross-sectional state during the manufacturing process of the solar cell module according to the first embodiment. Note that the thickness of each layer in Figures 6 to 8 is illustrative and may not be the same as that of the actual layers, including their relative sizes.

[0068] First, a surface protection layer 1 is prepared. Here, for example, a rectangular surface protection layer 1 is prepared, which is a resin film with weather resistance on both sides. As the weather-resistant resin, for example, a fluoropolymer resin is used. As a fluoropolymer resin, for example, FEP, ETFE, or ECTFE is used. Here, for example, a surface activation treatment such as corona treatment or plasma treatment is applied to the second surface 1s, which is one side of the surface protection layer 1. This can improve the adhesion between the surface protection layer 1 and the filler 4 in the lamination process described later.

[0069] Next, as shown in Figures 7 and 8, for example, a laminate 10s is formed by laminating a surface protective layer 1, a sheet 41s, a solar cell section 3, a support member 5, a sheet 42s, a sheet 42t, a fiber material 61, a sheet 71, and a back surface protective layer 2.

[0070] In the laminate 10s, the solar cell section 3 is located between two support members 5, which are spaced apart in the X direction. At this time, wiring is appropriately arranged to be drawn out from the solar cell section 3 to the outside of the solar cell panel 10 and connected to a terminal box or the like. For example, multiple solar cell elements 31 of the solar cell section 3 are interconnected by a first wiring material 32 and a second wiring material 33. A third wiring material 34 is also connected to the solar cell section 3.

[0071] The sheet 41s is a sheet made of resin (such as IO or EVA) that forms the basis of the first filler 41. The sheet 41s is located between the surface protection layer 1 and the solar cell section 3, and between the surface protection layer 1 and the support member 5. In other words, the sheet 41s is located on top of the surface protection layer 1, and the solar cell section 3 and the support member 5 are located on top of the sheet 41s. In a plan view, the sheet 41s has a rectangular shape, which is an example of a square shape.

[0072] Sheets 42s and 42t are sheets made of a resin (such as IO or EVA) that forms the basis of the second filler 42. Sheets 42s and 42t may contain pigments.

[0073] Sheets 42s and 42t are located between the back protective layer 2 and the solar cell section 3, and between the back protective layer 2 and the support member 5. In other words, sheet 42s is positioned so that both ends are sandwiched between the support member 5, and sheet 42t is positioned so that both ends face the support member 5. In a plan view, sheets 42s and 42t have a rectangular shape, which is an example of a square shape.

[0074] The fiber material 61 is a fiber material that constitutes the fiber layer 6. The fiber material 61 becomes the fiber layer 6 when the sheet 42t or sheet 71 facing the fiber material 61 is impregnated during the lamination process described later. The fiber material 61 is located between the back protective layer 2 and the sheet 42t.

[0075] Sheet 71 is a sheet made of resin (such as IO or EVA). Sheet 71 may be made of the same material as sheets 41s, 42s, or 42t. Sheet 71 is located between the back protective layer 2 and the fiber material 61. The back protective layer 2 is located on top of sheet 71.

[0076] Next, for example, a lamination process is performed on the laminate 10s. Here, for example, a laminating device (laminator) is used to integrate the laminate 10s. For example, in a laminator, the laminate 10s is placed on a heater plate in the chamber, and the chamber is depressurized from 50 Pascals (Pa) to about 150 Pa while the laminate 10s is heated from 100 degrees Celsius (100°C) to about 200 degrees Celsius (200°C). At this time, the sheets 41s, 42s, 42t and 71 become somewhat fluid due to the heating. In this state, the laminate 10s is integrated by pressing it in the Z direction with a pressing body such as a diaphragm sheet inside the chamber.

[0077] In this process, the fiber layer 6 is formed when the sheet 42t or sheet 71 impregnates the fiber material 61. In other words, the fiber layer 6 is formed when a resin such as IO, which is in a fluid state, impregnates the fiber material 61.

[0078] In the fiber layer 6 formed after lamination, voids (spaces) that are not impregnated by the sheet 42t or sheet 71 may be partially formed in the gaps between the fiber material 61. These voids (spaces) may be completely contained within the fiber layer 6, or they may open to the outside on the surface of the fiber layer 6.

[0079] As shown in Figures 7 and 8, if the fiber material 61 is not impregnated with an impregnating agent (e.g., resin) before lamination, and only the adjacent resin sheet (e.g., sheet 42t or sheet 71) is impregnated into the fiber material 61 during lamination, voids (spaces) that are not impregnated with the impregnating agent (e.g., resin) are likely to form in the fiber layer 6 after lamination. On the other hand, if the fiber material 61 is pre-impregnated with an impregnating agent (e.g., resin) before lamination, and then incorporated into the laminate structure for lamination, and the fiber layer 6 is formed by further lamination, voids (spaces) that are not impregnated with the impregnating agent (e.g., resin) are less likely to form. Furthermore, the amount (or proportion) of voids (spaces) formed in the fiber layer 6 can be adjusted by adjusting the amount of impregnating agent pre-impregnated into the fiber material 61 before lamination.

[0080] After lamination, terminal boxes and other components may be attached to the solar panel 10 as appropriate. At this time, for example, the wiring that has been brought out from the solar cell section 3 to the outside of the solar panel 10 is connected to the terminals inside the terminal box as appropriate. This completes the assembly of the solar module 100.

[0081] In the example described above, the solar panel 10, including the support member 5, is integrated by lamination. Therefore, compared to a structure in which an external frame (not shown) is attached to the solar panel 10 with screws or the like instead of the support member 5, the assembly of the solar panel 10 is easier.

[0082] <Laminated structure near the support member> Figure 9 is a cross-sectional view showing an example of the laminated structure near the support member. Figure 9 corresponds to the laminated structure of region RA in Figure 2. The filler material 4, which is filled between the surface protective layer 1 and the fiber layer 6, is filled in a state where it is integrated within that region. In Figure 9, however, the dotted lines indicate the virtual boundary lines of the sheets 41s, 42s, and 42t before lamination, which become the filler material 4 after lamination.

[0083] As shown in Figure 9, the support member 5 and the fiber layer 6 are arranged to overlap in a plan view (in other words, viewed along the Z-axis). In the case shown in Figure 9, the second surface 5s of the support member 5 is located on the +Z side of the first surface 6f of the fiber layer 6. Note that the arrangement is not limited to the case where the entire support member 5 and the fiber layer 6 overlap in a plan view, as shown in Figure 9; it may also be an arrangement where only a part of the support member 5 and the fiber layer 6 overlap in a plan view.

[0084] The fiber layer 6 prevents air from moving from the back protective layer 2 to the front protective layer 1. Specifically, the resin impregnated into the fiber material 61 in the fiber layer 6 prevents air from moving.

[0085] The thicknesses of each layer in Figure 9 are illustrative, but the total thickness of the laminated structure located on the surface protection layer 1 side of the fiber layer 6 is greater than the total thickness of the laminated structure located on the back protection layer 2 side of the fiber layer 6. Specifically, the total thickness of the surface protection layer 1, filler 4, and support member 5 is greater than the total thickness of the adhesive layer 7 and back protection layer 2.

[0086] According to the stacked configuration shown in Figure 9, the fire resistance of the solar cell module 100 can be improved.

[0087] Specifically, for example, when the solar cell module 100 is heated due to a fire, the movement of air, particularly oxygen, from the back protective layer 2 to the front protective layer 1 can be obstructed, thereby reducing the combustion rate and delaying the time until ignition.

[0088] In a high-temperature environment, the filler 4 becomes fluid, and through-holes are formed in the filler 4, penetrating from the back protective layer 2 to the front protective layer 1. This promotes oxygen supply and increases the combustion rate in the solar cell module 100. However, with the above configuration, the resin impregnated in the fiber material 61 has lower fluidity than the filler 4, which is in a fluid state and not held by the fiber material 61, because it is held in the gaps between the fiber material 61. Furthermore, the lower the gap ratio of the fiber material 61, in other words, the higher the proportion of fiber material 61 present in a plan view, the easier it is for the fiber layer 6 to hold the filler 4. Therefore, it becomes more difficult for through-holes that promote oxygen supply to be formed, and the combustion rate can be reduced.

[0089] Furthermore, in the configuration shown in Figure 9, the support member 5 and the fiber layer 6 are positioned overlapping in a plan view, which also prevents air movement in the vicinity of the support member 5.

[0090] Furthermore, for example, if the filler material 4 becomes fluid due to the solar cell module 100 being placed in a high-temperature environment, the gaps between the fibers 61 in the fiber layer 6 hold the fluid filler material 4, thereby suppressing the filler material 4 from flowing down in the -Z direction of the solar cell module 100. This helps to prevent the spread of fire to the roof or other surfaces on which the solar cell module 100 is attached.

[0091] Furthermore, in the configuration shown in Figure 9, the filler material 4 that flows down along the side surface and second surface 5s of the support member 5 can also be reliably held in the gaps of the fiber material 61.

[0092] Furthermore, in the fiber layer 6, if there are partial voids (spaces) in the gaps between the fiber material 61 that are not impregnated by the sheet 42t or sheet 71, the resin held in the gaps between the fiber material 61 can obstruct air movement, while the space can hold the fluid filler 4, effectively suppressing the flow of the filler 4. In addition, the effect of the space holding the fluid filler 4 can be enhanced, thereby inhibiting air movement.

[0093] Furthermore, for example, because the softening point of the fibers in the fiber layer 6 is higher than the combustion reaction temperature of the filler 4, the fiber layer 6 can maintain its shape for a longer period of time when heated by a fire. This delays the combustion of the filler 4 when burning from the -Z direction. Also, because the thermal conductivity of the fiber layer 6 is higher than that of the filler 4, heat can be dissipated towards the filler 4 when burning from the -Z direction. This extends the time it takes for the fiber layer 6 to reach a high temperature, allowing it to maintain its shape for a longer period. Therefore, it is possible to suppress the exposure of other components to fire due to deformation of the fiber layer 6. This increases the fire resistance of the solar cell module.

[0094] Furthermore, the fiber layer 6 can also improve the temperature cycle resistance of the solar cell module 100. Specifically, because the fiber layer 6 has a high Young's modulus and a low coefficient of thermal expansion, it can suppress thermal expansion of the peripheral components of the solar cell element 31. As a result, it is possible to suppress problems such as disconnection of the wiring material (first wiring material 32, second wiring material 33, or third wiring material 34) connected to the solar cell element 31 due to thermal expansion of the peripheral components of the solar cell element 31.

[0095] The above effect is achieved when the Young's modulus of the fiber layer 6, in the state where the impregnating material is impregnated, is greater than the Young's modulus of the filler material 4 covering the solar cell element 31, and the coefficient of linear expansion of the fiber layer 6, in the state where the impregnating material is impregnated, is smaller than the coefficient of linear expansion of the filler material 4 covering the solar cell element 31. Note that the Young's modulus of the fiber layer 6, in the state where IO is impregnated into the glass fibers, is 1.64 GPa, and the coefficient of linear expansion is 36 × 10⁻¹⁰ -6 The coefficient of thermal expansion is 110 × 10⁻¹⁰. Furthermore, the Young's modulus of IO as filler 4 is 0.28 GPa, and the coefficient of thermal expansion is 110 × 10⁻¹⁰. -6 It is / K.

[0096] Figure 10 is a cross-sectional view showing an example of the laminated structure near the support member. Figure 10 corresponds to the laminated structure of region RB in Figure 5. The filler material 4, which is filled between the surface protective layer 1 and the fiber layer 6, is filled in a state where it is integrated within that region. In Figure 10, however, the dotted lines indicate the virtual boundary lines of the sheets 41s, 42s, and 42t before lamination, which become the filler material 4 after lamination.

[0097] In the configuration shown in Figure 10, in addition to the configuration shown in Figure 9, mounting holes 11 are formed. The mounting holes 11 are holes into which fixing devices 111 are inserted to connect the mounting target part and the solar panel 10 when attaching the solar panel 10 to a mounting target part such as a roof, thereby securing the two together.

[0098] <Mounting holes> The mounting holes 11 are holes that connect the surface protection layer 1, the filler 4, the support member 5, the fiber layer 6, the adhesive layer 7, and the back surface protection layer 2. The mounting holes 11 may be formed all at once in the laminated structure after lamination, or they may be formed sequentially before and after lamination. In the case where the mounting holes 11 are formed sequentially before and after lamination, it is conceivable that holes are partially formed in at least the support member 5 and the fiber material 61 before lamination, and then after lamination, holes connecting the remaining layers (surface protection layer 1, filler 4, adhesive layer 7, and back surface protection layer 2) are extended and formed while appropriately aligning with the holes already formed in the support member 5 and the fiber layer 6.

[0099] A fixing device 111 is inserted into the mounting hole 11. The fixing device 111 has a pin portion 111a that faces the mounting hole 11 from the +Z direction side and a base portion 111b that faces the mounting hole 11 from the -Z direction side. By inserting the pin portion 111a into the mounting hole 11 from the +Z direction side and making contact with or engaging the base portion 111b from the -Z direction side of the mounting hole 11, the solar cell panel 10 is fixed by being sandwiched from both sides in the Z direction at the location of the mounting hole 11.

[0100] According to the stacked configuration shown in Figure 10, the fire resistance of the solar cell module 100 can be improved.

[0101] Specifically, when the solar cell panel 10 is fixed by inserting the pin portion 111a into the mounting hole 11 and facing the base portion 111b, the fixing state between the support member 5 and the fiber layer 6 becomes strong.

[0102] Therefore, even if the fiber layer 6 deforms in a high-temperature environment, for example, if the edges of the fiber layer 6 may peel off from the filler 4, the positional relationship between the support member 5 and the fiber layer 6 is more easily maintained. As a result, air movement or the flow of the filler 4 in areas where the fiber layer 6 is not located can be suppressed.

[0103] <Second Embodiment> A solar cell module according to this embodiment will now be described. In the following description, components that are the same as or similar to those described in the embodiments described above will be denoted by the same reference numerals, and their detailed descriptions will be omitted as appropriate.

[0104] <Laminated structure near the support member> Figure 11 is a cross-sectional view showing an example of a laminated structure near a support member according to a second embodiment. Figure 11 corresponds to another example of the laminated structure of region RA in Figure 2.

[0105] In the configuration shown in Figure 11, in addition to the configuration shown in Figure 9, a fiber layer 8 and a buffer layer 9 are provided. Either the fiber layer 8 or the buffer layer 9 may be provided. The filler 4 filled between the surface protective layer 1 and the fiber layer 6 is filled in an integrated state in that region, but in Figure 11, the imaginary boundary lines of the sheets 41s, 42sa, 42sb, and 42t before lamination, which become the filler 4 after lamination, are shown by dotted lines. Here, sheets 42sa and 42sb are obtained by further dividing sheet 42s shown in Figures 7 and 8 in the Z direction before and after lamination of the fiber layer 8.

[0106] <Fiber layer> The fiber layer 8 is a layer formed, for example, by impregnating at least a portion of the gaps between the fiber material with an impregnating material. The fiber material and impregnating material of the fiber layer 8 may be the same as or different from the fiber material and impregnating material of the fiber layer 6. The fiber layer 8 has, for example, a first surface 8f and a second surface 8s located on the opposite side of the first surface 8f. The first surface 8f of the fiber layer 8 is facing the solar cell element 31. The second surface 8s of the fiber layer 8 is facing the buffer layer 9. The first surface 8f and the second surface 8s of the fiber layer 8 are covered with a filler material 4. In Figure 11, the filler material 4 is filled between the fiber layer 8 and the support member 5, but the fiber layer 8 may be in contact with the support member 5 in the X direction. The fiber layer 8 is formed, for example, by impregnating the fiber material with a fluid resin during a lamination process. In the fiber layer 8 formed after lamination, voids (spaces) that are not impregnated with resin may be partially formed in the gaps between the fibers.

[0107] The fiber layer 8 shown in Figure 11 is positioned to overlap the entire solar cell element 31 in a plan view. However, the fiber layer 8 may overlap only a portion of the solar cell element 31, or it may be positioned to surround the solar cell element 31 in a plan view, excluding only the portion that overlaps with the solar cell element 31 in a plan view. When the fiber layer 8 is positioned to surround the solar cell element 31 in a plan view, it is possible to reduce the area on which the fiber layer 8 is formed while hindering air movement in the region that does not overlap with the solar cell element 31 in a plan view, thereby contributing to improved fire resistance of the solar cell module.

[0108] The thickness of the fiber layer 8 is, for example, about 0.01 mm to 0.5 mm. The fiber material included in the fiber layer 8 is, for example, a non-combustible or flame-retardant fiber material such as glass fiber. The impregnating material used to impregnate the fiber material is, for example, IO, epoxy resin, EVA, POE, or polymethyl methacrylate resin. When the fiber material is glass fiber, the softening point is about 844°C. The thermal conductivity of the glass constituting the glass fiber is 1.0 W / mK, and when the impregnating material is the same IO as the filler 4, the thermal conductivity of IO is 0.3 W / mK or higher and 0.4 W / mK or lower. For this reason, the thermal conductivity of the fiber layer 8, which is a composite material of glass fiber and impregnating material, is considered to be higher than that of the filler 4. The impregnating material impregnating the fiber material in the fiber layer 8 hinders the movement of air from the back protective layer 2 side to the front protective layer 1 side. Furthermore, if the gap ratio of the fiber material used in the fiber layer 8 is 64% or less, preferably 24.3% or less, and even more preferably 3.3% or less, the fiber layer 8 can further improve the fire resistance of the solar cell module 100.

[0109] The fiber layer 8 can also improve the temperature cycle resistance of the solar cell module 100. Specifically, the fiber layer 8 has a high Young's modulus and a low coefficient of thermal expansion, which can suppress thermal expansion of the peripheral components of the solar cell element 31. As a result, it is possible to suppress problems such as disconnection of the wiring material (first wiring material 32, second wiring material 33, or third wiring material 34) connected to the solar cell element 31 due to thermal expansion of the peripheral components of the solar cell element 31.

[0110] The above effect is achieved when the Young's modulus of the fiber layer 8, in the state where the impregnating material is impregnated, is greater than the Young's modulus of the filler material 4 covering the solar cell element 31, and the coefficient of linear expansion of the fiber layer 8, in the state where the impregnating material is impregnated, is smaller than the coefficient of linear expansion of the filler material 4 covering the solar cell element 31. Note that the Young's modulus of the fiber layer 8, in the state where IO is impregnated into the glass fibers, is 1.64 GPa, and the coefficient of linear expansion is 36 × 10⁻¹⁰. -6The temperature is / K. Furthermore, since the fiber layer 8 is positioned closer to the solar cell element 31 than the fiber layer 6, it can exert a stronger influence than the fiber layer 6 on suppressing thermal expansion around the solar cell element 31, thereby effectively suppressing problems such as disconnection of the wiring material connected to the solar cell element 31.

[0111] <Buffer layer> The buffer layer 9 is a layer made of resin. The buffer layer 9 has, for example, a first surface 9f and a second surface 9s located on the opposite side of the first surface 9f. The first surface 9f of the buffer layer 9 faces the second surface 8s of the fiber layer 8. The second surface 9s of the buffer layer 9 faces the first surface 6f of the fiber layer 6. In addition, the first surface 9f, the second surface 9s, and the sides of the buffer layer 9 are covered with filler 4.

[0112] The thickness of the buffer layer 9 is, for example, about 0.1 mm to 2 mm. The material constituting the buffer layer 9 may be, for example, PET or POE. The buffer layer 9 may also be a laminated structure of multiple materials. For example, the buffer layer 9 may be a laminated structure consisting of PET and POE. When the buffer layer 9 is PET, the combustion reaction temperature is approximately 375°C, and the thermal conductivity is 0.15 W / mK or higher and 0.24 W / mK or lower. Furthermore, when the buffer layer 9 is PET, the Young's modulus is 4 GPa, and the coefficient of linear expansion is 20 × 10⁻¹⁰ -6 It is / K.

[0113] When a buffer layer 9 is provided, an ultraviolet absorber may be included in the adhesive portion (not shown here) of the surface protection layer 1 or the surface protection layer 1 consisting of multiple layers. The ultraviolet absorber is more likely to reduce the transmission of light (ultraviolet light) with a wavelength of 360 nm or less by 10% or less, and if the buffer layer 9 contains PET, it may also reduce only the transmission of light (ultraviolet light) with a wavelength of 320 nm or less by 10% or less. With such a configuration, for example, when the buffer layer 9 contains PET, degradation of PET due to ultraviolet light can be suppressed. Furthermore, by reducing only the transmission of light with a wavelength of 360 nm or less without reducing the transmission of light with a wavelength of approximately 380 nm or 400 nm, it is possible to suppress the decrease in power generation in the solar cell element 31 while suppressing degradation of PET due to ultraviolet light. Furthermore, by reducing only the transmission of light with a wavelength of 320 nm or less, it is possible to effectively reduce light transmission and suppress the decrease in power generation in the solar cell element 31 while suppressing degradation of PET due to ultraviolet light.

[0114] The stacked configuration shown in Figure 11 can improve the fire resistance of the solar cell module.

[0115] Specifically, the position of the fiber layer 8 between the solar cell element 31 and the fiber layer 6 allows the impregnating material in the fiber layer 8 to obstruct the movement of air from the back protective layer 2 to the front protective layer 1. Furthermore, the filler material 4, which flows down in a fluid state, can be held in the gaps between the fibers, thereby suppressing the spread of fire to roofs and other surfaces.

[0116] Furthermore, because the softening point of the fibers in the fiber layer 8 is higher than the combustion reaction temperature of the filler 4, the fiber layer 8 can maintain its shape for a longer period of time when heated. This delays the combustion of the filler 4 facing the first surface 8f when burning from the -Z direction, and delays the combustion of the filler 4 facing the second surface 8s when burning from the +Z direction. In addition, because the thermal conductivity of the fiber layer 8 is higher than that of the filler 4, heat can be efficiently dissipated towards the filler 4 facing the first surface 8f when burning from the -Z direction, and towards the filler 4 facing the second surface 8s when burning from the +Z direction. This slows down the rate at which the temperature rises on the side exposed to the fire, and extends the time until ignition.

[0117] Furthermore, since the buffer layer 9 located between the solar cell element 31 and the fiber layer 6 is encased in the filler material 4, in other words, the entire buffer layer 9, including its first surface 9f, second surface 9s, and sides, is covered by the filler material 4, the ignition of the buffer layer 9 is suppressed until the filler material 4 becomes fluid and holes are formed that promote air movement. As a result, even if the combustion reaction temperature of the buffer layer 9 is low, the combustion of the buffer layer 9 can be delayed by being encased in the filler material 4, which has a higher combustion reaction temperature than the buffer layer 9.

[0118] Furthermore, in Figure 11, the filler material 4 is also filled between the fiber layer 8 and the support member 5, and no voids (air bubbles) are formed in that area where the filler material 4 is not filled. In other words, the fiber layer 8 and the support member 5 are adjacent to each other in a plan view, with the filler material 4 in between.

[0119] With this configuration, air bubbles will not form even in areas where the fiber layer 8 and the support member 5 are not in contact. Therefore, it is possible to suppress the air bubbles from acting as air passages and promoting combustion.

[0120] <Third Embodiment> A solar cell module according to this embodiment will now be described. In the following description, components that are the same as or similar to those described in the embodiments described above will be denoted by the same reference numerals, and their detailed descriptions will be omitted as appropriate.

[0121] <Laminated structure near the support member> Figure 12 is a cross-sectional view showing an example of a laminated structure near a support member according to a third embodiment. Figure 12 corresponds to another example of the laminated structure of region RA in Figure 2.

[0122] In the configuration shown in Figure 12, in addition to the configuration shown in Figure 9, a fiber layer 12 and an adhesive layer 13 are provided. If either the material of the surface protective layer 1 or the material of the fiber layer 12 is a material that can be fused to adjacent layers by heating during the lamination process, the adhesive layer 13 may not be provided.

[0123] <Fiber layer> The fiber layer 12 is a layer formed by impregnating at least a portion of the gaps between the fiber material with an impregnating material. The fiber material and impregnating material of the fiber layer 12 may be the same as or different from the fiber material and impregnating material of the fiber layers 6 and 8. The fiber layer 12 is translucent. The fiber layer 12 has, for example, a first surface 12f and a second surface 12s located on the opposite side of the first surface 12f. The first surface 12f of the fiber layer 12 faces the surface protection layer 1 via the adhesive layer 13. The second surface 12s of the fiber layer 12 faces the filler material 4. In other words, the second surface 12s of the fiber layer 12 is covered with the filler material 4. Also, the second surface 12s of the fiber layer 12 faces the first element surface 31f of the solar cell element 31 via the filler material 4. For example, the fiber layer 12 is sufficiently impregnated with an impregnating material such as resin before forming a laminated structure by lamination.

[0124] The thickness of the fiber layer 12 is, for example, about 0.01 mm to 0.5 mm. For example, glass fibers are used as the fiber material contained in the fiber layer 12. For example, IO, epoxy resin, EVA, POE, or polymethyl methacrylate resin are used as the impregnating material that impregnates the fiber material. The impregnating material impregnating the fiber material in the fiber layer 12 prevents the movement of air from the back protective layer 2 side to the front protective layer 1 side.

[0125] When a fiber layer 12 is provided, the surface protective layer 1 or the adhesive layer 13 described later may contain an ultraviolet absorber. The ultraviolet absorber should reduce the transmission of light with a wavelength of 360 nm or less (ultraviolet light) to 10% or less. With such a configuration, for example, when epoxy resin is included as the impregnating material for the fiber layer 12, degradation of the epoxy resin due to ultraviolet light can be suppressed. Furthermore, by reducing only the transmission of light with a wavelength of 360 nm or less without reducing the transmission of light with a wavelength of approximately 380 nm or 400 nm, it is possible to suppress the decrease in power generation in the solar cell element 31 while suppressing degradation of the epoxy resin due to ultraviolet light.

[0126] <Adhesive layer> The adhesive layer 13 is a layer that adheres the fiber layer 12 and the surface protection layer 1. The adhesive layer 13 can be considered as one of the layers that make up the surface protection layer 1. In this case, the adhesive layer 13 may contain an ultraviolet absorber. The adhesive layer 13 has, for example, a first surface 13f and a second surface 13s located on the opposite side of the first surface 13f. The first surface 13f of the adhesive layer 13 is, for example, adhered to the second surface 1s of the surface protection layer 1. The second surface 13s of the adhesive layer 13 is, for example, adhered to the first surface 12f of the fiber layer 12.

[0127] The thickness of the adhesive layer 13 is, for example, about 0.1 mm to 0.5 mm. The material constituting the adhesive layer 13 may be, for example, IO, EVA, or POE. The adhesive layer 13 may also be made of the same material as the filler 4.

[0128] Furthermore, if either the material of the surface protection layer 1 or the material of the fiber layer 12 is a material that can be fused to an adjacent layer by heating during the lamination process, then the adhesive layer 13 may not be provided.

[0129] The stacked configuration shown in Figure 12 can improve the fire resistance of the solar cell module.

[0130] Specifically, even if the surface protective layer 1 is burned away, the fiber layer 12 covering the solar cell element 31 remains, thus suppressing the burning and scattering of the solar cell element 31.

[0131] In addition, in Figure 12, at least one of the fiber layer 8 and buffer layer 9 shown in Figure 11 may be further provided.

[0132] <Fourth Embodiment> A solar cell module according to this embodiment will now be described. In the following description, components that are the same as or similar to those described in the embodiments described above will be denoted by the same reference numerals, and their detailed descriptions will be omitted as appropriate.

[0133] <Laminated structure near the support member> Figure 13 is a cross-sectional view showing an example of a laminated structure near a support member according to the fourth embodiment. Figure 13 corresponds to another example of the laminated structure of region RA in Figure 2.

[0134] In the configuration shown in Figure 13, in addition to the configuration shown in Figure 9, a mounting hole 11b is formed, and a rivet 112 is provided that is fixed in place while inserted into the mounting hole 11b. The mounting hole 11b is a separate hole from the mounting hole 11 shown in Figure 10.

[0135] <Mounting holes> The mounting holes 11b are holes that connect the surface protective layer 1, the filler 4, the support member 5, the fiber layer 6, the adhesive layer 7, and the back protective layer 2. The mounting holes 11b may be formed collectively in the laminated structure after lamination, or they may be formed in at least the support member 5 and the fiber material 61 before lamination, and then holes connecting the remaining layers (surface protective layer 1, filler 4, adhesive layer 7, and back protective layer 2) are formed after lamination while appropriately aligning them.

[0136] <rivet> The mounting hole 11b is fixed with a rivet 112 inserted into it. The rivet 112 is a fixing member that is fixed to the mounting hole 11b, for example, by crimping. The diameter of the rivet 112 is larger at the part that contacts the surface of the mounting hole 11b on the +Z direction side (i.e., the first surface 1f of the surface protective layer 1) and at the part that contacts the surface of the mounting hole 11b on the -Z direction side (i.e., the second surface 2s of the back surface protective layer 2), and because the rivet 112 penetrates the laminated structure, the laminated structure can be fixed in the Z direction.

[0137] According to the stacked configuration shown in Figure 13, the fire resistance of the solar cell module 100 can be improved.

[0138] Specifically, when the solar panel 10 is fixed in the Z direction by inserting a rivet 112 into the mounting hole 11b, the fixing state between the support member 5 and the fiber layer 6 becomes strong.

[0139] Therefore, even if the fiber layer 6 deforms in a high-temperature environment, for example, if the edges of the fiber layer 6 may peel off from the filler 4, the positional relationship between the support member 5 and the fiber layer 6 is more easily maintained. As a result, air movement or the flow of the filler 4 in areas where the fiber layer 6 is not located can be suppressed.

[0140] This disclosure includes the following:

[0141] (1) In one embodiment, the solar cell module comprises a light-transmitting resin surface protective layer, a first fiber layer in which a first impregnating material is impregnated into a first fiber material, a solar cell element disposed between the surface protective layer and the first fiber layer, a support member disposed between the surface protective layer and the first fiber layer, and a filler that covers the solar cell element and the support member and is filled between the surface protective layer and the first fiber layer, wherein the support member overlaps with the first fiber layer in a plan view, but does not overlap with the solar cell element in a plan view.

[0142] (2) In the solar cell module described in (1) above, at least a first hole is formed that connects the support member and the first fiber layer.

[0143] (3) In the solar cell module described in (1) or (2) above, spaces may be formed in the gaps between the first fiber material where the first impregnation material is not impregnated.

[0144] (4) In the solar cell module described in any one of (1) to (3) above, the softening point of the fiber material in the first fiber layer may be higher than the combustion reaction temperature of the filler, and the thermal conductivity of the first fiber layer may be higher than the thermal conductivity of the filler.

[0145] (5) A solar cell module according to any one of (1) to (4) above, further comprising a second fiber layer disposed between the solar cell element and the first fiber layer, wherein the second fiber material is impregnated with the second impregnation material, and the filler is filled in such a way that it covers the second fiber layer, the softening point of the fiber material in the second fiber layer may be higher than the combustion reaction temperature of the filler, and the thermal conductivity of the second fiber layer may be higher than the thermal conductivity of the filler.

[0146] (6) In the solar cell module described in (5) above, the second fiber layer and the support member may be adjacent to each other via the filler.

[0147] (7) A solar cell module according to any one of (1) to (6) above, further comprising a resin buffer layer disposed between the solar cell element and the first fiber layer, wherein the filler is filled in such a way that it encompasses the buffer layer, and the combustion reaction temperature of the buffer layer may be lower than the combustion reaction temperature of the filler.

[0148] (8) In the solar cell module described in any one of (1) to (7) above, the third fiber material is impregnated with the third impregnating material, and the module further comprises a translucent third fiber layer disposed between the surface protective layer and the solar cell element, wherein the filler is filled in such a way that it covers the third fiber layer.

[0149] (9) A solar cell module according to any one of (1) to (8) above may further include a fixing member that fixes at least the surface protective layer, the support member and the first fiber layer, with a second hole formed that connects at least the surface protective layer, the support member and the first fiber layer, and which penetrates the second hole.

[0150] (10) In a solar cell module described in any one of (1) to (9) above, the surface protective layer may reduce the transmission of light with a wavelength of 360 nm or less more than the transmission of light with a wavelength longer than 360 nm.

[0151] (11) In the solar cell module described in (10) above, the surface protective layer may reduce the transmission of light with a wavelength of 360 nm or less to 10% or less.

[0152] (12) In the solar cell module described in any one of (1) to (9) above, the surface protective layer may reduce the transmission of light with a wavelength of 320 nm or less more than the transmission of light with a wavelength longer than 320 nm.

[0153] (13) The solar cell module described in (12) above, wherein the surface protective layer reduces the transmission of light with a wavelength of 320 nm or less to 10% or less.

[0154] (14) In the solar cell module described in any one of (1) to (13) above, the Young's modulus of the first fiber layer may be greater than the Young's modulus of the filler, and the coefficient of linear expansion of the first fiber layer may be less than the coefficient of linear expansion of the filler.

[0155] (15) In the solar cell module described in (5) above, the Young's modulus of the second fiber layer may be greater than the Young's modulus of the filler, and the coefficient of linear expansion of the second fiber layer may be less than the coefficient of linear expansion of the filler.

[0156] (16) In the solar cell module described in any one of (1) to (15) above, the gap ratio of the first fiber material may be 64% or less.

[0157] (17) In the solar cell module described in any one of (1) to (16) above, the gap ratio of the first fiber material may be 24.3% or less.

[0158] (18) In the solar cell module described in any one of (1) to (17) above, the gap ratio of the first fiber material may be 3.3% or less. [Explanation of Symbols]

[0159] 1 Surface protective layer 2. Back protective layer 4 Filling material 5. Support Member 6 fiber layers 7 Adhesive layer 8 fiber layers 9 Buffer layer 12 fiber layers 13 Adhesive layer 31 Solar cell elements 61 Fiber materials 71 seats 100 solar modules 112 rivets

Claims

1. A translucent resin surface protective layer, A first fiber layer in which the first fiber material is impregnated with the first impregnation material, A solar cell element is disposed between the surface protective layer and the first fiber layer, A support member is disposed between the surface protective layer and the first fiber layer, The solar cell element and the support member are covered by a filler material which is filled between the surface protective layer and the first fiber layer. The support member overlaps with the first fiber layer in a plan view, and does not overlap with the solar cell element in a plan view. Solar cell module.

2. The solar cell module according to claim 1, At least a first hole is formed that connects the support member and the first fiber layer, Solar cell module.

3. A solar cell module according to claim 1 or 2, A space is formed in the gap between the first fibrous material in a state where the first impregnating material is not impregnated. Solar cell module.

4. A solar cell module according to claim 1 or 2, The softening point of the fibrous material in the first fiber layer is higher than the combustion reaction temperature of the filler. The thermal conductivity of the first fiber layer is higher than that of the filler. Solar cell module.

5. A solar cell module according to claim 1 or 2, The second fiber material is impregnated with the second impregnation material, and the second fiber layer is further disposed between the solar cell element and the first fiber layer. The filler is filled in such a way that it covers the second fiber layer. The softening point of the fibrous material in the second fiber layer is higher than the combustion reaction temperature of the filler. The thermal conductivity of the second fiber layer is higher than that of the filler. Solar cell module.

6. The solar cell module according to claim 5, The second fiber layer and the support member are adjacent to each other via the filler, Solar cell module.

7. A solar cell module according to claim 1 or 2, The solar cell element and the first fiber layer are further provided with a resin buffer layer disposed between them. The filler is filled in such a state that it encompasses the buffer layer. The combustion reaction temperature of the buffer layer is lower than that of the filler. Solar cell module.

8. A solar cell module according to claim 1 or 2, The third fiber material is impregnated with the third impregnating material, and the third fiber layer is further provided as a translucent third fiber layer disposed between the surface protective layer and the solar cell element. The filler is filled in such a way that it covers the third fiber layer. Solar cell module.

9. A solar cell module according to claim 1 or 2, At least the surface protective layer, the support member, and the first fiber layer are connected by a second hole, The device further comprises a fixing member that penetrates the second hole and fixes at least the surface protective layer, the support member, and the first fiber layer, Solar cell module.

10. A solar cell module according to claim 1 or 2, The aforementioned surface protective layer reduces the transmission of light with a wavelength of 360 nm or less more than the transmission of light with a wavelength longer than 360 nm. Solar cell module.

11. The solar cell module according to claim 10, The aforementioned surface protective layer reduces the transmission of light with a wavelength of 360 nm or less to 10% or less. Solar cell module.

12. A solar cell module according to claim 1 or 2, The aforementioned surface protective layer reduces the transmission of light with a wavelength of 320 nm or less more than the transmission of light with a wavelength longer than 320 nm. Solar cell module.

13. The solar cell module according to claim 12, The aforementioned surface protective layer reduces the transmission of light with a wavelength of 320 nm or less to 10% or less. Solar cell module.

14. A solar cell module according to claim 1 or 2, The Young's modulus of the first fiber layer is greater than the Young's modulus of the filler. The coefficient of linear expansion of the first fiber layer is smaller than the coefficient of linear expansion of the filler. Solar cell module.

15. The solar cell module according to claim 5, The Young's modulus of the second fiber layer is greater than that of the filler. The coefficient of linear expansion of the second fiber layer is smaller than the coefficient of linear expansion of the filler. Solar cell module.

16. A solar cell module according to claim 1 or 2, The gap ratio of the first fiber material is 64% or less. Solar cell module.

17. A solar cell module according to claim 1 or 2, The gap ratio of the first fiber material is 24.3% or less. Solar cell module.

18. A solar cell module according to claim 1 or 2, The gap ratio of the first fiber material is 3.3% or less. Solar cell module.

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