Solar cell module

Abstract

To provide a solar cell module capable of suppressing deterioration of a photovoltaic cell.SOLUTION: A solar cell module 1 according to one aspect of the present invention includes a first light-transmissive member 11, a second light-transmissive member 12, an intermediate adhesive film 13 that is disposed between the first light-transmissive member 11 and the second light-transmissive member 12 and adheres the first light-transmissive member 11 and the second light-transmissive member 12, and a photovoltaic cell 15 enclosed in the intermediate adhesive film 13. At least one of the first light-transmissive member 11 and the second light-transmissive member 12 is a glass plate including first main surfaces 21 and 31 and second main surfaces 22 and 32, a Sn concentration in the second main surfaces 22 and 32 of the glass plate is higher than the Sn concentration in the first main surfaces 21 and 31, and the glass plate is disposed such that the second main surfaces 22 and 32 of the glass plate are on the photovoltaic cell 15 side.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a solar cell module. [Background technology]

[0002] In recent years, the use of solar cell modules equipped with multiple solar power generation cells has been promoted in order to utilize natural energy. In particular, solar cell modules in which multiple solar power generation cells are enclosed inside laminated glass have been widely used.

[0003] Patent Document 1 discloses a technique relating to a glass building material in which a plurality of photovoltaic cells are arranged between two glass plates. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2018 / 056286 Summary of the Invention [Problem to be solved by the invention]

[0005] As explained in the background art, solar cell modules in which multiple solar cells are sealed inside laminated glass are widely used. Such solar cell modules have a configuration in which multiple solar cells are sealed inside an intermediate adhesive film that bonds two glass sheets together, for example.

[0006] However, since the glass plate contains sodium, the sodium from the glass plate may diffuse into the intermediate adhesive film and reach the solar cell, which may cause degradation of the solar cell.

[0007] In view of the above problems, an object of the present invention is to provide a solar cell module that can suppress deterioration of the solar power generation cells. [Means for solving the problem]

[0008] A solar cell module according to one aspect of the present invention is as follows.

[0009] [1] a first light-transmitting member; a second light-transmitting member disposed so as to face the first light-transmitting member; an intermediate adhesive film disposed between the first light-transmitting member and the second light-transmitting member and adhering the first light-transmitting member and the second light-transmitting member; a photovoltaic cell encapsulated within the intermediate adhesive film; At least one of the first light-transmitting member and the second light-transmitting member is a glass plate having a first main surface and a second main surface, the Sn concentration in the second main surface of the glass plate is higher than the Sn concentration in the first main surface, The glass plate is arranged so that the second main surface of the glass plate faces the photovoltaic cell. Solar cell module.

[0010] [2] The solar cell module according to [1], wherein the net intensity based on the Sn when the second main surface side of the glass plate is measured by fluorescent X-ray analysis is 300 cps or more.

[0011] [3] The solar cell module according to [1] or [2], wherein the glass plate has a gradient in Na concentration in the thickness direction, and the Na concentration of the second main surface of the glass plate is lower than the Na concentration of the first main surface.

[0012] [4] The solar cell module according to [3], wherein the Na concentration D2 (mass%) of the second main surface is D0-2.5≦D2≦D0-0.5 when the Na concentration D0 (mass%) at the center in the thickness direction of the glass plate is used as a reference.

[0013] [5] The solar cell module according to [3], wherein the Na concentration D2 (mass%) of the second main surface is D0-1.50≦D2≦D0-0.80 when the Na concentration D0 (mass%) at the center in the thickness direction of the glass plate is used as a reference.

[0014] [6] The solar cell module according to [3], wherein the concentration difference (D1-D2) between the Na concentration D1 (mass%) on the first main surface of the glass plate and the Na concentration D2 (mass%) on the second main surface is 0.30 mass% or more and 0.90 mass% or less.

[0015] [7] The solar cell module according to any one of [1] to [6], wherein the glass plate has a thickness of 2 mm or more and 19 mm or less.

[0016] [8] The solar cell module according to any one of [1] to [7], wherein the solar cell is a silicon-based solar cell.

[0017] [9] the photovoltaic cell is a monofacial photovoltaic cell, the glass plate is arranged so that the second main surface of the glass plate faces the light-receiving surface side of the solar photovoltaic cell. The solar cell module according to any one of [1] to [8].

[0018]

[10] the first light-transmitting member and the second light-transmitting member are made of the glass plates, the glass plate constituting the first light-transmitting member is arranged so that the second main surface of the glass plate faces the photovoltaic cell, the glass plate constituting the second light-transmitting member is arranged so that the second main surface of the glass plate faces the photovoltaic cell side; The solar cell module according to any one of [1] to [8].

[0019]

[11] the solar cell is disposed on the second light-transmitting member side in the thickness direction of the intermediate adhesive film, the second light-transmitting member is made of the glass plate, the glass plate constituting the second light-transmitting member is arranged so that the second main surface of the glass plate faces the photovoltaic cell side; The solar cell module according to any one of [1] to [8].

[0020]

[12] the photovoltaic cell is disposed on the first light-transmitting member side in the thickness direction of the intermediate adhesive film, the first light-transmitting member is made of the glass plate, the glass plate constituting the first light-transmitting member is arranged so that the second main surface of the glass plate faces the photovoltaic cell side; The solar cell module according to any one of [1] to [8]. [Effects of the Invention]

[0021] According to the present invention, it is possible to provide a solar cell module capable of suppressing deterioration of the solar power generation cells. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a front view showing an example of a solar cell module according to an embodiment; [Figure 2] 1 is a cross-sectional view showing an example of a solar cell module according to an embodiment. [Figure 3] FIG. 10 is a cross-sectional view showing another example of the configuration of the solar cell module according to the embodiment. [Figure 4] FIG. 10 is a cross-sectional view showing another example of the configuration of the solar cell module according to the embodiment. [Figure 5] FIG. 10 is a cross-sectional view showing another example of the configuration of the solar cell module according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a front view showing an example of a solar cell module according to an embodiment, Fig. 2 is a cross-sectional view showing the example of a solar cell module according to an embodiment, taken along line II-II in Fig. 1.

[0024] As shown in FIGS. 1 and 2, a solar cell module 1 according to this embodiment includes a first light-transmitting member 11, a second light-transmitting member 12, an intermediate adhesive film 13, and a photovoltaic cell 15. As shown in FIG. 2, the first light-transmitting member 11 and the second light-transmitting member 12 are plate-like members having light transmissivity, and can typically be configured using glass plates. Hereinafter, this embodiment will be described with reference to a case where the first light-transmitting member 11 and the second light-transmitting member 12 are configured using glass plates. Hereinafter, the first light-transmitting member 11 and the second light-transmitting member 12 will also be referred to as the first glass plate 11 and the second glass plate 12. The solar cell module 1 (laminated glass) according to this embodiment can be suitably used as a building material such as window glass for buildings. Details of the first glass plate 11 and the second glass plate 12 will be described later.

[0025] The intermediate adhesive film 13 is disposed between the first glass plate 11 and the second glass plate 12, and bonds the first glass plate 11 and the second glass plate 12 together. For example, when forming the solar cell module 1, the first glass plate 11, the intermediate adhesive film 13, the solar cell 15, the intermediate adhesive film 13, and the second glass plate 12 are laminated in this order, and this laminate is heated and pressurized to bond them together, thereby forming the solar cell module 1. At this time, the intermediate adhesive film 13 disposed below the solar cell 15 and the intermediate adhesive film 13 disposed above it are heated and melted, so that the completed solar cell module 1 consists of a single layer of intermediate adhesive film 13.

[0026] The thickness of the intermediate adhesive film 13 is preferably 0.38 mm or more and 2.28 mm or less. The intermediate adhesive film 13 may be made of EVA (ethylene-vinyl acetate copolymer) resin, PVB (polyvinyl butyral) resin, ionomer resin, COP (cycloolefin polymer), polyurethane, PVC (polyvinyl chloride), POE (polyolefin elastomer), TPO (olefin-based thermoplastic elastomer), or the like. The intermediate adhesive film 13 may also be made of a combination of these materials.

[0027] The photovoltaic cells 15 are sealed between the first glass plate 11 and the second glass plate 12, specifically inside the intermediate adhesive film 13. As shown in FIG. 1, the photovoltaic cells 15 are arranged in an array in the horizontal and vertical directions when the solar cell module 1 is viewed in a plan view. FIG. 1 shows, as an example, a configuration in which a plurality of photovoltaic cells 15 are arranged in an array of four cells in the horizontal direction and six cells in the vertical direction (i.e., a 4×6 array). Note that the configuration shown in FIG. 1 is just an example, and the number of photovoltaic cells 15 arranged in the horizontal and vertical directions can be determined as desired. The photovoltaic cells 15 inside the solar cell module 1 are connected to each other by conductive interconnectors (not shown).

[0028] The photovoltaic cells 15 can be configured using photovoltaic cells of silicon-based single crystal type, silicon-based polycrystalline type, amorphous silicon type, thin film silicon type, CIGS type, organic thin film type, dye-sensitized type, perovskite type, or the like. As shown in FIG. 1, each photovoltaic cell 15 has a rectangular shape. For example, each photovoltaic cell 15 may have a square, rectangular, or circular shape. Furthermore, for example, a monofacial photovoltaic cell may be used as the photovoltaic cell 15. Furthermore, a bifacial photovoltaic cell may be used as the photovoltaic cell 15.

[0029] In the solar cell module 1 according to this embodiment, at least one of the first glass plate 11 and the second glass plate 12 is arranged so that the Sn concentration on the second main surface of the glass plate is higher than the Sn concentration on the first main surface, and the second main surface of the glass plate faces the solar cell.

[0030] 2 , the first glass plate 11 is a glass plate having a first main surface 21 and a second main surface 22, and the Sn concentration in the second main surface 22 of the first glass plate 11 is higher than the Sn concentration in the first main surface 21. In other words, a region 23 with a high Sn concentration is formed on the second main surface 22 side of the first glass plate 11 from the surface to a predetermined depth. In this embodiment, the first glass plate 11 is arranged so that the second main surface 22 side of the first glass plate 11, i.e., the region 23 with a high Sn concentration, faces the photovoltaic cell 15. In other words, the first glass plate 11 is arranged so that the second main surface 22 side of the first glass plate 11 faces the light-receiving surface of the photovoltaic cell 15.

[0031] Similarly, the second glass plate 12 is a glass plate having a first main surface 31 and a second main surface 32, and the Sn concentration on the second main surface 32 of the second glass plate 12 is higher than the Sn concentration on the first main surface 31. In other words, a region 33 with a high Sn concentration is formed on the second main surface 32 side of the second glass plate 12 from the surface to a predetermined depth. In this embodiment, the second glass plate 12 is arranged so that the second main surface 32 side of the second glass plate 12, i.e., the region 33 with a high Sn concentration, faces the photovoltaic cell 15.

[0032] The solar cell module 1 according to this embodiment has such a configuration, and therefore can provide a solar cell module that can suppress deterioration of the photovoltaic power generation cells.

[0033] That is, a solar cell module has a configuration in which, for example, multiple photovoltaic cells are sealed inside an intermediate adhesive film that bonds two glass plates. Here, since the glass plates contain Na components, the Na components of the glass plates may diffuse into the intermediate adhesive film and reach the photovoltaic cells. When the Na components diffuse into the photovoltaic cells, there is a problem in that the photovoltaic cells deteriorate.

[0034] Therefore, in this embodiment, at least one of the first glass plate 11 and the second glass plate 12 is configured so that the Sn concentration on the second main surfaces 22, 32 arranged on the solar cell 15 side is higher than the Sn concentration on the first main surfaces 21, 31. When the Sn concentration on the second main surfaces 22, 32 on the solar cell 15 side is increased in this way, the Sn concentration of the asymmetric ions Sn 2+ The presence of Na suppresses the interdiffusion of ions, so the Na component (Na + ) can be prevented from diffusing to the solar cell side, and therefore deterioration of the solar cell can be prevented.

[0035] The Sn concentrations of the first and second glass plates 11, 12 can be measured using an X-ray fluorescence analyzer. In this embodiment, the net intensity based on Sn when the second main surfaces 22, 32 sides of the first and second glass plates 11, 12 are measured by X-ray fluorescence analysis is preferably 300 cps or more, more preferably 800 cps or more, and even more preferably 1500 cps or more. Furthermore, the net intensity based on Sn when the first main surfaces 21, 31 sides of the first and second glass plates 11, 12 are measured by X-ray fluorescence analysis is approximately 12 to 17 kcps.

[0036] The net intensity based on Sn measured by the X-ray fluorescence analysis is a value measured using a wavelength dispersive X-ray fluorescence analyzer (ZSX Primus IV, manufactured by Rigaku Corporation). The net intensity is the X-ray intensity at the peak angle of Sn minus the background intensity. The measurement conditions are as follows:

[0037] X-ray tube (X-ray source): Rh (rhodium) Excitation conditions: Tube voltage 50 kV, tube current 50 mA Measurement area (X-ray irradiation range): 30 mm diameter Measurement line: Sn-LA Measuring instrument: Proportional counter (PC)

[0038] The thickness of the first and second glass plates 11, 12 is preferably 2 mm or more and 19 mm or less, more preferably 3 mm or more and 15 mm or less, and even more preferably 5 mm or more and 12 mm or less.

[0039] As described above, when the Na component reaches the photovoltaic cell 15, the electrical characteristics of the photovoltaic cell 15 change, and the output of the photovoltaic cell decreases. In the above configuration, by increasing the Sn concentration on the second main surfaces 22 and 32, the Na component (Na + ) is prevented from diffusing toward the photovoltaic cell side. In this embodiment, the glass plate may be configured so that the Sn concentration on the second main surfaces 22, 32 is high and the Na concentration on the second main surfaces 22, 32 is low.

[0040] Specifically, in this embodiment, a glass plate having a gradient in Na concentration in the thickness direction may be used as the first glass plate 11, and the first glass plate 11 may be configured so that the Na concentration at the second main surface 22 is lower than the Na concentration at the first main surface 21. That is, a region 23 having a low Na concentration may be formed on the second main surface 22 side of the first glass plate 11 from the surface to a predetermined depth. In this embodiment, the first glass plate 11 may be arranged so that the second main surface 22 side of the first glass plate 11, i.e., the region 23 having a low Na concentration, faces the photovoltaic cell 15. That is, the first glass plate 11 may be arranged so that the second main surface 22 side of the first glass plate 11 faces the light-receiving surface of the photovoltaic cell 15.

[0041] Similarly, in the present embodiment, a glass plate having a gradient in Na concentration in the thickness direction may be used as the second glass plate 12, and the second glass plate 12 may be configured so that the Na concentration on the second main surface 32 is lower than the Na concentration on the first main surface 31. That is, a region 33 having a low Na concentration may be formed on the second main surface 32 side of the second glass plate 12 from the surface to a predetermined depth. The second glass plate 12 may be arranged so that the second main surface 32 side of the second glass plate 12, i.e., the region 33 having a low Na concentration, faces the photovoltaic cell 15.

[0042] With this configuration, it is possible to effectively prevent the Na component from diffusing from the first glass plate 11 to the photovoltaic cells 15. Therefore, it is possible to prevent a decrease in the output of the photovoltaic cells 15. In this specification, for convenience, the high Sn concentration region 23 and the low Na concentration region 23 of the first glass plate 11 are illustrated using the same reference numerals, but the high Sn concentration region 23 and the low Na concentration region 23 may have different thicknesses. The same applies to the region 33 of the second glass plate 12.

[0043] When the Na concentration D0 (mass %) at the center (bulk) in the thickness direction of the first and second glass plates 11 and 12 is used as a reference, the Na concentration D2 (mass %) of the second main surfaces 22 and 32 preferably falls within the range of D0-2.5≦D2≦D0-0.5, and more preferably D0-1.50≦D2≦D0-0.80. In this specification, the Na concentration is the concentration converted into Na2O, which is an oxide of Na.

[0044] Furthermore, it is preferable that the range of the Na concentration D1 (mass %) of the first main surfaces 21 and 31, based on the Na concentration D0 (mass %) at the center (bulk) in the thickness direction of the first and second glass plates 11 and 12, is D0-1.0≦D1≦D0.

[0045] Furthermore, the concentration difference (D1-D2) between the Na concentration D1 (mass%) on the first main surfaces 21, 31 of the first and second glass plates 11, 12 and the Na concentration D2 (mass%) on the second main surfaces is preferably 0.30 mass% or more and 0.90 mass% or less, and more preferably 0.50 mass% or more and 0.90 mass% or less.

[0046] The Na concentrations on the first main surfaces 21, 31 and the second main surfaces 22, 32 of the first and second glass plates 11, 12 can be measured using the wavelength dispersive X-ray fluorescence analyzer described above. For example, by creating a calibration curve showing the relationship between X-ray intensity and Na concentration in advance using a standard sample of Na element, the Na concentration can be determined from the X-ray intensity of the measured sample.

[0047] Furthermore, the decrease in output of the photovoltaic cell 15 due to the Na component is particularly significant in silicon-based photovoltaic cells. Therefore, the effect of the present embodiment of the invention is particularly pronounced when the photovoltaic cell 15 is a silicon-based photovoltaic cell.

[0048] In the present embodiment, the glass sheets (first glass sheet 11, second glass sheet 12) may be made of, for example, soda-lime glass, aluminosilicate glass, borosilicate glass, alkali-free glass, quartz glass, etc. The glass sheets are manufactured using, for example, a float method, a roll-out method, a fusion method, a slot-down method, etc., but are not limited to these manufacturing methods.

[0049] As an example, in this embodiment, soda lime glass having the following matrix composition may be used as the glass plate: Note that the numerical values ​​are expressed in mass % on an oxide basis.

[0050] (Mother composition of soda-lime glass) SiO2: 65-75% Al2O3: 0-5% MgO: 0-6% CaO: 5-15% Na2O: 10-20% K2O: 0-5% SO3: 0-2% Fe2O3: 0-2% TiO2: 0-2%

[0051] In this embodiment, the Sn concentration and Na concentration on the second main surfaces 22, 32 of the glass plate 11 can be adjusted by the following method. For example, in this embodiment, the glass is obtained by melting blended raw materials at approximately 1500°C, refining the obtained molten glass, forming it into a plate by a float method or the like, and cutting it into a predetermined shape.

[0052] In this case, the Sn concentration on the second main surfaces 22, 32 (bottom surfaces) of the glass sheet 11 may be adjusted by adjusting the residence time of the molten glass in the float bath (molten metal tin). Specifically, the longer the residence time of the molten glass in the float bath, the higher the Sn concentration on the bottom surface. Conversely, the shorter the residence time of the molten glass in the float bath, the lower the Sn concentration on the bottom surface.

[0053] Furthermore, when the glass sheet coming out of the float bath is slowly cooled, the amount of at least one acidic gas selected from SO gas, HCl gas, and HF gas blown onto the glass sheet may be adjusted to adjust the Na concentration on the second main surfaces 22, 32 of the glass sheet 11. Specifically, by increasing the amount of acidic gas blown onto the glass sheet, the alkali component NaO of the glass sheet can be extracted from the glass, and the Na concentration on the second main surfaces 22, 32 of the glass sheet can be reduced.

[0054] In the solar cell module 1 shown in Fig. 2, the photovoltaic cell 15 may be a monofacial photovoltaic cell, or may be a bifacial photovoltaic cell.

[0055] Fig. 3 is a cross-sectional view showing another example of the configuration of a solar cell module according to an embodiment. In the solar cell module 1a shown in Fig. 3, the Sn concentration in the second main surface 22 of the first glass plate 11 is higher than the Sn concentration in the first main surface 21, and the second main surface 22 of the first glass plate 11 is configured to face the solar cell 15. In the configuration example shown in Fig. 3, the second glass plate 12 may be configured using a normal glass plate (i.e., a glass plate in which the Sn concentration and Na concentration are not taken into consideration), or a plate-like member made of a resin material may be used instead of the second glass plate 12. Note that the configuration example shown in Fig. 3 is suitable for use with solar cell 15 that is a single-sided light-receiving solar cell, that is, a solar cell 15 whose light-receiving surface faces the first glass plate 11.

[0056] Fig. 4 is a cross-sectional view showing another example of the configuration of a solar cell module according to an embodiment. In the solar cell module 1b shown in Fig. 4, the solar cell 15 is arranged on the second glass plate 12 side in the thickness direction of the intermediate adhesive film 13. The second glass plate 12 can be the same glass plate as the second glass plate 12 shown in Fig. 2.

[0057] In the solar cell module 1b shown in FIG. 4, the photovoltaic cells 15 are arranged on the second glass plate 12 side in the thickness direction of the intermediate adhesive film 13. Therefore, the thickness of the intermediate adhesive film 13 between the first glass plate 11 and the photovoltaic cells 15 can be increased, so that the photovoltaic cells 15 can be effectively protected even if a strong force is applied to the first glass plate 11 arranged outside the building. Furthermore, by arranging the second glass plate 12 in consideration of the Sn concentration of the second glass plate 12 on the side closer to the photovoltaic cells 15, deterioration of the photovoltaic cells can be suppressed. Furthermore, by arranging the second glass plate 12 in consideration of the Na concentration of the second glass plate 12 on the side closer to the photovoltaic cells 15, a decrease in output of the photovoltaic cells 15 can be effectively suppressed.

[0058] 4, the first light-transmitting member 11 may be made of a glass plate or a plate-like member made of a resin material. When the first light-transmitting member 11 is made of a glass plate, a normal glass plate may be used as the first glass plate 11, or a glass plate in which the Sn concentration and Na concentration on the second main surface 22 are taken into consideration may be used, as in the configuration example shown in FIG.

[0059] Fig. 5 is a cross-sectional view showing another example of the configuration of a solar cell module according to an embodiment. In a solar cell module 1c shown in Fig. 5, a solar cell 15 is arranged on the first glass plate 11 side in the thickness direction of the intermediate adhesive film 13. The same glass plate as the first glass plate 11 shown in Fig. 2 can be used for the first glass plate 11.

[0060] In the solar cell module 1c shown in FIG. 5, the photovoltaic cells 15 are arranged on the first glass plate 11 (glass plate on the light-receiving surface side) side in the thickness direction of the intermediate adhesive film 13. This allows the thickness of the intermediate adhesive film 13 between the first glass plate 11 and the photovoltaic cells 15 to be thin, thereby increasing the amount of power generated by the photovoltaic cells 15. Furthermore, by arranging the first glass plate 11 in consideration of the Sn concentration of the first glass plate 11 on the side closer to the photovoltaic cells 15, deterioration of the photovoltaic cells can be suppressed. Furthermore, by arranging the first glass plate 11 in consideration of the Na concentration of the first glass plate 11 on the side closer to the photovoltaic cells 15, a decrease in output from the photovoltaic cells 15 can be effectively suppressed.

[0061] 5, the second light-transmitting member 12 may be made of a glass plate or a plate-like member made of a resin material. When the second light-transmitting member 12 is made of a glass plate, a normal glass plate may be used as the second glass plate 12, or a glass plate in consideration of the Sn concentration and Na concentration on the second main surface 32 may be used, as in the configuration example shown in FIG. [Example]

[0062] The Sn concentration and Na concentration were measured on the first and second main surfaces of the glass plate of each sample. Float glass (float plate glass manufactured by AGC Corporation) having each thickness was prepared as each sample. Each sample was pre-heat-treated at a temperature of 680°C for 10 minutes. In this example, samples that had not been heat-treated were also measured, but no significant difference in Sn concentration and Na concentration was observed between the presence and absence of heat treatment. Therefore, this example shows only the results of samples that had been heat-treated.

[0063] The Sn concentration and Na concentration were measured using a wavelength dispersive X-ray fluorescence analyzer (ZSX Primus IV manufactured by Rigaku Corporation) under the following measurement conditions.

[0064] X-ray tube (X-ray source): Rh (rhodium) Excitation conditions: Tube voltage 50 kV, tube current 50 mA Measurement area (X-ray irradiation range): 30 mm diameter Measurement line (Sn): Sn-LA Measurement line (Na): Na-KA Measuring instrument: Proportional counter (PC)

[0065] In this example, the net Sn intensity was used to indicate the Sn concentration. The net Sn intensity was determined by subtracting the background intensity from the X-ray intensity at the Sn peak angle. Table 1 shows the Sn concentrations (net Sn intensity) on the first and second principal surfaces of the glass plate for each sample.

[0066] [Table 1]

[0067] As shown in Table 1, the Sn concentration on the second main surface of each sample was higher than the Sn concentration on the first main surface. Specifically, the net strength of the first main surface was 12 to 17 (cps), but the net strength of the second main surface was 779 to 1049 (cps), and the Sn concentration was higher on the second main surface.

[0068] In this example, the Na concentration was determined by preparing a calibration curve showing the relationship between X-ray intensity and Na concentration using a standard Na sample. In other words, the Na concentration corresponding to the X-ray intensity of the measured sample was determined using the calibration curve. The bulk Na concentration refers to the Na concentration near the center (bulk) of the glass plate in the thickness direction. The bulk Na concentration was determined by polishing a certain amount of the surface of the glass plate and then analyzing the composition with an X-ray fluorescence analyzer. Table 2 shows the Na concentrations (converted to Na2O) on the first and second main surfaces of the glass plate for each sample.

[0069] [Table 2]

[0070] As shown in Table 2, the Na concentration (D2) of the second principal surface of each sample was lower than the Na concentration (D1) of the first principal surface. The difference (D1 - D2) between the Na concentration (D1) of the first principal surface and the Na concentration (D2) of the second principal surface of each sample was 0.34 to 0.83 (wt%). The difference (D1 - D0) between the Na concentration (D1) of the first principal surface and the Na concentration (D0) of the bulk was -0.94 to -0.53 (wt%). The difference (D2 - D0) between the Na concentration (D2) of the second principal surface and the Na concentration (D0) of the bulk was -1.41 to -0.88 (wt%).

[0071] As described above, the second main surface of the glass plate according to this example has a higher Sn concentration (lower Na concentration) than the first main surface. Therefore, by placing the second main surface of the glass plate according to this example on the solar cell side when constructing a solar cell module, it is possible to manufacture a solar cell module that can suppress deterioration of the solar cell.

[0072] The present invention has been described above in accordance with the above-mentioned embodiment, but the present invention is not limited to the configuration of the above-mentioned embodiment, and naturally includes various modifications, alterations, and combinations that a person skilled in the art can make within the scope of the invention as defined in the claims of this application. [Explanation of symbols]

[0073] 1, 1a, 1b, 1c solar cell modules 11 First light-transmitting member (first glass plate) 12 Second light-transmitting member (second glass plate) 13 Intermediate adhesive film 15 Photovoltaic Cells 21, 31 First main surface 22, 32 Second main surface

Claims

1. a first light-transmitting member; a second light-transmitting member disposed opposite the first light-transmitting member; an intermediate adhesive film disposed between the first light-transmitting member and the second light-transmitting member and adhering the first light-transmitting member and the second light-transmitting member; a photovoltaic cell encapsulated within the intermediate adhesive film; at least one of the first light-transmitting member and the second light-transmitting member is a glass plate having a first main surface and a second main surface; the Sn concentration in the second main surface of the glass plate is higher than the Sn concentration in the first main surface, The glass plate is arranged so that the second main surface of the glass plate faces the photovoltaic cell. Solar cell module.

2. The solar cell module according to claim 1 , wherein the net strength based on the Sn when the second main surface side of the glass plate is measured by fluorescent X-ray analysis is 300 cps or more.

3. 3 . The solar cell module according to claim 1 , wherein the glass plate has a gradient in sodium concentration in a thickness direction, and the sodium concentration of the second main surface of the glass plate is lower than the sodium concentration of the first main surface.

4. The Na concentration D at the center of the glass plate in the thickness direction ０ The Na concentration D of the second principal surface when based on (mass%) ２ (mass%) is D ０ -2.50≦D ２ ≦D ０ The solar cell module according to claim 3, wherein the refractive index is −0.

50.

5. The Na concentration D at the center of the glass plate in the thickness direction ０ The Na concentration D of the second principal surface when based on (mass%) ２ (mass%) is D ０ -1.50≦D ２ ≦D ０ The solar cell module according to claim 3, wherein the refractive index is −0.

80.

6. Na concentration D on the first main surface of the glass plate １ (mass%) and the Na concentration D on the second principal surface ２ (mass%) and the concentration difference (D １ -D ２ 4. The solar cell module according to claim 3, wherein the content of ZnO is 0.30 mass % or more and 0.90 mass % or less.

7. 3. The solar cell module according to claim 1, wherein the glass plate has a thickness of 2 mm or more and 19 mm or less.

8. The solar cell module according to claim 1 or 2, wherein the solar cell is a silicon-based solar cell.

9. the photovoltaic cell is a monofacial photovoltaic cell, the glass plate is arranged so that the second main surface of the glass plate faces the light-receiving surface side of the solar photovoltaic cell, The solar cell module according to claim 1 or 2.

10. the first light-transmitting member and the second light-transmitting member are made of the glass plate, the glass plate constituting the first light-transmitting member is arranged so that the second main surface of the glass plate faces the photovoltaic cell, the glass plate constituting the second light-transmitting member is arranged so that the second main surface of the glass plate faces the photovoltaic cell side; The solar cell module according to claim 1 or 2.

11. the solar cell is disposed on the second light-transmitting member side in the thickness direction of the intermediate adhesive film, the second light-transmitting member is made of the glass plate, the glass plate constituting the second light-transmitting member is arranged so that the second main surface of the glass plate faces the photovoltaic cell side; The solar cell module according to claim 1 or 2.

12. the solar cell is disposed on the first light-transmitting member side in the thickness direction of the intermediate adhesive film, the first light-transmitting member is made of the glass plate, the glass plate constituting the first light-transmitting member is arranged so that the second main surface of the glass plate faces the photovoltaic cell, The solar cell module according to claim 1 or 2.

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