JP6542631B2 - Solar cell module and method of manufacturing the same - Google Patents

Description

  The present invention relates to a solar cell module and a method of manufacturing the same, and more particularly, to a solar cell module including a light transmitting substrate containing ions and a solar cell and a method of manufacturing the same.

  At present, as a clean energy that does not use fossil fuels, solar power generation technology that uses sunlight is attracting attention. In solar power generation, solar energy is converted to electrical energy by a solar battery cell to obtain power by irradiating the solar cell module configured with a translucent substrate and the solar battery cell with sunlight.

  In recent years, particularly in Europe where mega solar is widespread, the "PID (Potential Induced Degradation) phenomenon" in which the output of the solar cell module is reduced has become a problem. The PID phenomenon is a phenomenon in which when a high voltage is applied to a solar battery cell particularly in a high temperature and humidity environment, a current leak occurs in the solar battery cell and the output is reduced. The PID phenomenon is considered to be one of the reasons that sodium or the like contained in a light-transmissive substrate such as glass is ionized and this ion diffuses into the solar battery cell.

  Then, the solar cell module provided with the sodium diffusion prevention functional layer between the surface side light transmissive member containing sodium and a solar cell element conventionally is known (for example, refer to patent documents 1). By providing such a sodium diffusion preventing functional layer, it is possible to prevent the sodium of the surface side light transmitting member from being diffused to the solar cell element, and to extend the time until the power generation performance of the solar cell element is reduced. It is possible to provide a highly reliable solar cell module that can withstand the

JP 2001-291881 A (claim 1, paragraph 0107, etc.)

  Patent Document 1 mentions an inorganic oxide film such as a titanium oxide film, a tin oxide film, a zinc oxide film, an aluminum oxide film, or a magnesium oxide film as a diffusion prevention layer (paragraph 0090). However, the inorganic oxide film described in the examples is only silicon oxide (paragraphs 0075 and 0086), and no other inorganic oxide film is specifically disclosed.

  The diffusion prevention layer is required to prevent the diffusion of ions for a long period of time to suppress the PID phenomenon. Furthermore, since the diffusion prevention layer is provided near the solar cell element (cell), when the diffusion prevention layer itself deteriorates the light transmittance, the initial electromotive force decreases and the performance as a solar cell deteriorates. For this reason, the diffusion prevention layer is required to inhibit the transmission of sunlight as much as possible. However, conventional diffusion prevention layers do not satisfy both of these requirements.

  An object of the present invention is to provide a solar cell module which suppresses the PID phenomenon over a long period and has a good initial performance as a solar cell, and a method of manufacturing the same.

  As a result of intensive investigations to achieve the above object, the present inventors can suppress the PID phenomenon over a long period of time and increase the initial electromotive force by using magnesium oxide as the diffusion prevention layer. To complete the present invention.

  That is, according to the present invention, there are provided a solar battery cell for converting incident light into electricity, a translucent substrate which is located on the incident light side of the solar battery cell and contains or generates alkali metal ions, and the translucent substrate And an ion diffusion preventing layer disposed between the light transmitting substrate and the solar cell to prevent the diffusion of the ions from the light transmitting substrate to the solar cell, and the ion diffusion preventing layer contains magnesium oxide. It is a solar cell module characterized by doing.

Here, the magnesium oxide is preferably a powder having an average particle diameter of 1 to 500 nm. Moreover, it is preferable that the said ion diffusion prevention layer is a film body which laminated | stacked the said magnesium oxide and makes a film thickness of 0.1-10 micrometers.
Moreover, it is preferable that the said photovoltaic cell is sealed by the sealing material, and the said ion diffusion prevention layer is arrange | positioned by the interface of the said translucent board | substrate and the said sealing material. Alternatively, the ion diffusion preventing layer is preferably disposed on the surface of the solar battery cell.

  Further, the present invention covers a solar battery cell that converts incident light into electricity, a translucent substrate that is located on the incident light side of the solar battery cell, and that contains or generates alkali metal ions, and seals the solar battery. A solar cell module, comprising: a sealing material; and magnesium oxide is contained in at least a portion of the sealing material located between the solar battery cell and the translucent substrate. It is.

  In this case, the magnesium oxide is a powder having an average particle diameter of 1 to 500 nm, and the powder is preferably dispersed and contained in the sealing material.

  Further, the present invention is a method of manufacturing a solar cell module including a solar battery cell for converting incident light into electricity and a light transmitting substrate containing or generating alkali metal ions, wherein one surface of the light transmitting substrate Applying a dispersion of a solvent in which magnesium oxide is dispersed to one or both of the other surface of the solar battery cell, and evaporating the solvent to one surface of the light transmitting substrate and the solar battery cell An ion diffusion preventing layer forming step of forming a magnesium oxide film on one or both of the other surface and the light transmitting substrate such that one surface of the light transmitting substrate and the other surface of the solar battery cell face each other And an arranging step of arranging the solar battery cells, and a manufacturing method of a solar cell module.

  Alternatively, the present invention is a method of manufacturing a solar cell module including a solar cell that converts incident light into electricity, and a translucent substrate that contains or generates alkali metal ions, and sealing the solar cell. A sealing step of sealing with a material, a coating step of coating a dispersion comprising a solvent in which magnesium oxide is dispersed on the surface of the sealing material facing the light-transmissive substrate, and volatilizing the solvent An ion diffusion preventing layer forming step of forming a magnesium oxide film on the surface of the sealing material; and the light transmitting substrate and the light transmitting substrate so that the light transmitting substrate and the solar battery cell face each other with the magnesium oxide film interposed therebetween. And a placement step of placing a solar battery cell.

  In the above case, the magnesium oxide contained in the dispersion liquid is preferably a powder having an average particle diameter of 1 to 500 nm. Moreover, it is preferable that the said dispersion liquid is apply | coated at the said application | coating process so that the film thickness of the said magnesium oxide film | membrane may be 0.1-10 micrometers.

  Alternatively, according to the present invention, a solar battery cell for converting incident light into electricity, a light transmitting substrate containing or generating alkali metal ions, and at least the solar battery cell and the light transmitting substrate interposed therebetween. It is a manufacturing method of a solar cell module provided with the sealing material which seals the above-mentioned photovoltaic cell, A mixing process which mixes magnesium oxide powder with the above-mentioned sealing material in a dispersed state, The above-mentioned sealing material A method of manufacturing a solar cell module comprising: a sealing step of sealing, and a step of integrating the solar battery cell and the light transmitting substrate through the sealing material. is there.

  In this case, it is preferable that the magnesium oxide powder is a powder having an average particle diameter of 1 to 500 nm and be contained in the sealing material in a range of 0.1 to 30% by mass.

  ADVANTAGE OF THE INVENTION According to this invention, while suppressing a PID phenomenon over a long period of time, the solar cell module and the initial stage performance as a solar cell can also be provided favorable and its manufacturing method.

It is a schematic cross section which shows the solar cell module concerning a 1st embodiment of the present invention. It is a schematic cross section which shows the solar cell module which concerns on the 2nd Embodiment of this invention. It is a schematic cross section which shows the solar cell module which concerns on the 3rd Embodiment of this invention.

1. First Embodiment A solar cell module of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a solar cell module according to a first embodiment of the present invention. As shown to this figure, the solar cell module 10 is provided with the translucent board | substrate 11, the back sheet 12, the photovoltaic cell 13, the sealing material 14, and the ion diffusion prevention layer 15. As shown in FIG. In the present embodiment, it is described that light enters the solar battery cell 13 at least from the side of the translucent substrate 11.

  The translucent substrate 11 is disposed on the light receiving surface side of the solar battery cell 13, and is a transparent substrate having a property of transmitting light. As a material of translucent substrate 11, an inorganic material, an organic material, etc. can be used, for example. Examples of the inorganic material include glass, quartz, sapphire, and titania. Examples of the organic material include polyethylene terephthalate, polyethylene phthalate, polyimide, polystyrene, polyvinyl alcohol, fluorocarbon resin, vinyl chloride, polyolefin, cellulose, polycarbonate, polyacrylate and the like. Among these, glass is preferable in that it is widely spread and easily obtained, and the diffusion prevention effect of the ion diffusion preventing layer 15 is high, and white sheet glass having high transparency particularly at a wide wavelength is preferable.

  The translucent substrate 11 in the present invention contains ions inside, or has a property of generating ions under an environment such as high temperature / high humidity or high voltage. As the ions, although depending on the material of the translucent substrate 11, sodium ions and the like can be mentioned. In particular, when the material of the translucent substrate 11 described above is glass, sodium ions contained in the glass are considered as the cause of the PID phenomenon.

  The back sheet 12 is a substrate disposed on the side opposite to the light receiving surface side of the solar cell module 10. As the back sheet 12, the laminated body on which the resin film was laminated | stacked can be mentioned. Examples of the resin film include polyethylene terephthalate and fluorine resin. The laminate can include a metal layer such as aluminum foil. In the case where the solar cell module 10 generates electricity even when light is incident from the back sheet 12 side, the back sheet 12 preferably has light transparency like the light transmitting substrate 11. Examples of the material of the light transmitting substrate include the above-described glass and transparent resin.

  The solar battery cell 13 is disposed between the light transmitting substrate 11 and the back sheet 12 and has a property of converting incident light into electricity. The solar battery cell 13 can use well-known things, such as a silicon system and a compound type. Examples of silicon solar cells 13 include crystalline silicon and amorphous silicon. In addition, examples of compound solar cells 13 include GaAs, CIS, and CIGS. Among these, crystalline silicon solar cells are preferable because of relatively high photoelectric conversion efficiency.

  The solar cell 13 is electrically connected to the outside of the solar cell module 10 by an electrode (not shown). As an electrode, the metal electrode used by a common electronic component can be mentioned.

  The sealing material 14 has an insulating property, and has a function which seals and protects the photovoltaic cell 13 inside. As a material of the sealing material 14, a known material can be used, for example, ethylene vinyl acetate copolymer (EVA), polyethylene, ethylene acrylic copolymer, polyethylene terephthalate, polyethylene naphthalate, nylon 6 and the like It can be mentioned. Among these, ethylene vinyl acetate copolymer (EVA) is particularly preferable because of its good adhesion to the glass substrate and the like. The form of the sealing material 14 may be a sealing mold that covers the entire periphery of the solar battery cell 13 in a mold shape, or at least two sealing sheets sandwiched from the upper and lower surfaces of the solar battery cell 13 It is also good.

  The ion diffusion preventing layer 15 is disposed between the light transmitting substrate 11 and the solar battery cell 13 and has a function of preventing the diffusion of ions from the light transmitting substrate 11 to the solar battery cell 13. The ion diffusion preventing layer 15 of the present embodiment is disposed at the interface between the light transmitting substrate 11 and the sealing material 14.

  The ion diffusion preventing layer 15 is characterized by containing magnesium oxide. Magnesium oxide has high insulation and suppresses movement of ions, so that diffusion of ions from the light transmitting substrate 11 to the solar battery cell 13 can be suppressed by the ion diffusion prevention layer 15. Magnesium oxide is also characterized in that it has an ion diffusion preventing ability over a long period of time as compared with other metal oxides. Furthermore, magnesium oxide is highly transparent, and the ion diffusion preventing layer 15 hardly inhibits light incident on the solar battery cell 13, so that the solar battery module 10 has a characteristic that the initial output is high.

  Magnesium oxide can be used in powder form. The magnesium oxide powder can be obtained by a method of burning and oxidizing metal magnesium, or a method of firing and thermally decomposing magnesium hydroxide or magnesium carbonate. As magnesium hydroxide, those precipitated by the reaction of magnesium salt in seawater and calcium hydroxide can be used. Moreover, magnesite ore etc. can be used as magnesium carbonate. Furthermore, highly crystalline magnesium oxide powder obtained by pulverizing and classifying electrofused magnesium oxide can also be used. There is no restriction | limiting in particular as a calcination temperature of magnesium oxide, Any of a low temperature baking product, a high temperature baking product, or a fusion product can be used. Furthermore, highly crystalline magnesium oxide powder obtained by pulverizing and classifying electrofused magnesium oxide can also be used. There is no restriction | limiting in particular as a calcination temperature of magnesium oxide, Any of a low temperature baking product, a high temperature baking product, or a fusion product can be used.

  As the magnesium oxide powder, in particular, it is desirable that the average particle diameter is in the range of 1 to 500 nm, preferably 1 to 200 nm, and particularly 5 to 50 nm. With a particle size in this range, dispersion in a solvent is easy, and uniform dispersion in a solvent can be achieved. Therefore, a uniform film can be formed also at the time of application described later. Since the particle size is small and uniformly dispersed in the solvent, the packing property is excellent. Therefore, a dense film with few voids can be formed without passing through the process of reducing the voids between particles such as sintering. In addition, since the film is small and dense, the film thickness can be reduced. If the average particle diameter of the magnesium oxide powder is too large, the light transmitted through the ion diffusion preventing layer 15 is likely to be reflected by the particles, and the initial output of the solar cell module 10 tends to be low. On the other hand, when the average particle diameter of the magnesium oxide powder is too small, the particles are easily aggregated to deteriorate the dispersibility in the solvent described later, and the handleability tends to be deteriorated.

The average particle size of the magnesium oxide powder can be determined from the BET specific surface area value. Specifically, the average particle diameter can be calculated by converting it according to the following equation. The average particle diameter calculated from the following equation is a spherical equivalent average particle diameter, and specifically means the diameter of a sphere having the same surface area as that of the particles.
Average particle size (μm) = 6 / (S × ρ) (wherein, S is BET specific surface area (m ² / g), ρ is density of magnesium oxide powder (g / cm ³ ) Yes, 3.58 g / cm ³ ))

  The particle shape of the magnesium oxide powder is not particularly limited, and spherical, cubic, cuboid, polyhedron such as octahedron and tetrahedron, indeterminate, and fiber can be appropriately used. The purity of the magnesium oxide powder is usually 90% by mass or more, preferably 95% by mass or more, more preferably 98% by mass or more, and particularly preferably 99% by mass or more.

  The film thickness of the ion diffusion prevention layer 15 is usually in the range of 0.1 to 10 μm, preferably in the range of 0.2 to 5 μm, and particularly preferably in the range of 0.5 to 2 μm. Within this range, the amount of light passing through the ion diffusion preventing layer 15 can be secured to such an extent that the output of the solar cell module 10 hardly decreases. Moreover, if it is this range, since the ion diffusion prevention function of the ion diffusion prevention layer 15 can fully be ensured, output reduction can be suppressed over a long period. When the film thickness of the ion diffusion prevention layer 15 is less than 0.1 μm, the film thickness is too thin, and it becomes difficult to sufficiently exhibit the ion diffusion prevention function. On the contrary, when the film thickness of the ion diffusion preventing layer 15 exceeds 10 μm, the film thickness is too thick, the influence of light reflection by the ion diffusion preventing layer 15 becomes large, and the initial output of the solar cell module 10 decreases Inconvenient is likely to occur. When the average particle diameter of the magnesium oxide powder is 100 nm or more, the film thickness is preferably 1 μm or more.

  The ion diffusion prevention layer 15 can be formed by applying a dispersion liquid in which magnesium oxide is dispersed in a solvent on the surface of the translucent substrate 11 on the side facing the sealing material 14. Alternatively, the ion diffusion prevention layer 15 can be formed by applying a dispersion liquid in which magnesium oxide powder is dispersed in a solvent on the surface of the sealing material 14 on the side facing the light transmitting substrate 11.

  A polar solvent etc. can be mentioned as a solvent which disperse | distributes a magnesium oxide. Examples of polar solvents include polar organic solvents, and more specific examples include alcohols and ketones. Examples of alcohols include monohydric alcohols such as methanol, ethanol, propyl alcohol, isopropyl alcohol (isopropanol), butyl alcohol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, pentyl alcohol, isopentyl alcohol and the like. Can. Examples of ketones include acetone, ethyl methyl ketone and diethyl ketone. These alcohols and ketones may be used in combination of two or more.

  The polar organic solvent is preferably a monohydric alcohol having 1 to 5 carbon atoms, particularly preferably methanol, ethanol, isopropyl alcohol, butyl alcohol or a mixture thereof, of which methanol is particularly preferable. .

  The concentration of magnesium oxide contained in the dispersion is not particularly limited, but can be, for example, in the range of 0.1 to 30% by mass (wt%), preferably in the range of 1 to 20% by mass. It is. The concentration of magnesium oxide contained in the dispersion can be appropriately set, for example, in accordance with the film thickness of the ion diffusion preventing layer 15. As one example, when the film thickness of the ion diffusion preventing layer 15 is increased, the concentration of magnesium oxide contained in the dispersion is increased, and when the film thickness of the ion diffusion preventing layer 15 is decreased, the film is included in the dispersion. Lower the concentration of magnesium oxide. In addition, when making the film thickness of the ion diffusion prevention layer 15 thick, you may repeat application | coating several times, such as double coating other than the above-mentioned density | concentration adjustment.

  Coating of the dispersion liquid can be carried out by a known coating apparatus such as a roll coater, a die coater, a gravure coater, a doctor coater, a spray coater or the like. After application, the ion diffusion prevention layer 15 can be formed only by volatilizing the solvent by natural drying, warm air drying or the like, without passing through a step of densifying the film such as sintering.

  Next, a method of manufacturing the solar cell module 10 will be described. When the ion diffusion preventing layer 15 is formed on the surface of the light transmitting substrate 11, first, the dispersion liquid is applied to one surface of the light transmitting substrate 11 to form the ion diffusion preventing layer 15 (coating step) . Next, the solvent in the dispersion is volatilized to form the ion diffusion preventing layer 15 formed of a magnesium oxide film (ion diffusion preventing layer forming step). Furthermore, the periphery of the solar battery cell 13 is sealed with a sealing material 14 (sealing process). An electrode (not shown) connected to the solar battery cell 13 is extended to the outside of the sealing material 14. Subsequently, the sealing material 14 is sandwiched between the light transmitting substrate 11 and the back sheet 12 to bring the light transmitting substrate 11 and the back sheet 12 into close contact (arrangement step). Adhesion can be performed using a vacuum laminator or the like. Finally, the translucent substrate 11 and the back sheet 12 are fixed by a frame not shown.

  Alternatively, when the ion diffusion prevention layer 15 is formed on the surface of the sealing material 14, first, the periphery of the solar battery cell 13 is sealed with the sealing material 14 (sealing process). Next, the above dispersion liquid is applied to the surface of the sealing material 14 to form the ion diffusion preventing layer 15 (coating step). Furthermore, the solvent in the dispersion liquid is volatilized to form the ion diffusion preventing layer 15 formed of a magnesium oxide film (ion diffusion preventing layer forming step). Finally, the placement process is performed as described above to complete the solar cell module 10.

The solar cell module 10 having the above configuration can suppress the PID phenomenon for a long time. Specifically, when a voltage of −1000 V is applied to the solar cell module 10 under high temperature and high humidity conditions of 85 ° C. and 85% RH. The retention ratio of output after 24 hours is 80% or more, and can be 85% or more. Furthermore, the solar cell module 10 has an output retention rate of 70% or more after 48 hours under the above conditions, and can be 80% or more. Here, the retention ratio of output means a value calculated by the following equation.
Output holding ratio (%) = (power output value after 24 hours / initial (time zero) power output value) × 100

  In addition, since the solar cell module 10 has a property that the ion diffusion preventing layer 14 does not easily inhibit the incidence of sunlight, the initial electromotive force is high, and the solar cell module 10 has high output characteristics. Specifically, the output value of the initial power under the high temperature and high humidity conditions is 3.5 W or more, and can be 4.0 W or more.

2. Second Embodiment In the first embodiment described above, the ion diffusion prevention layer 15 is disposed at the interface between the light transmitting substrate 11 and the sealing material 14, but the ion diffusion prevention layer is limited to this. Alternatively, it may be provided as at least a part of the sealing material. Hereinafter, a second embodiment of the present invention will be described.

  FIG. 2 is a schematic cross-sectional view showing a solar cell module according to a second embodiment of the present invention. As shown to this figure, the solar cell module 20 is provided with the translucent board | substrate 21, the back sheet 22, the photovoltaic cell 23, and the sealing material 24 which also served as the ion diffusion prevention layer. The light transmitting substrate 21 can adopt the same structure as the light transmitting substrate 11 of the first embodiment, the back sheet 22 the back sheet 12, and the solar cells 23 the solar cells 13, so The detailed explanation is omitted here.

  Unlike the sealing material 14 of the first embodiment, the sealing material 24 of the present embodiment contains magnesium oxide. That is, magnesium oxide is mix | blended with base materials, such as resin, and the sealing material 24 of this embodiment has a function as an ion diffusion prevention layer. As a base material of the sealing material 24, an ethylene vinyl acetate copolymer etc. can be mentioned similarly to the sealing material 14 mentioned above. As magnesium oxide, the same one as the first embodiment described above can be used.

  When the sealing material 24 is a sealing mold, magnesium oxide powder is mixed in a dispersed state with a resin as a base material (mixing process), and the solar battery cell 23 is sealed by coating the surface of the solar battery cell 23 or the like. Then, the solar battery cell 23 and the light transmitting substrate 21 are integrated with the sealing material 24 interposed therebetween. The concentration of magnesium oxide contained in the sealing material 24 is not particularly limited, but can be, for example, in the range of 0.1 to 30% by mass (wt%), preferably 1 to 20% by mass. It is in the range. Moreover, there is no restriction | limiting in particular as an average particle diameter of magnesium oxide powder, It is preferable to exist in the range of 1-500 nm.

  On the other hand, when the sealing material 24 is a sealing sheet, magnesium oxide can be apply | coated to the surface at the side of the photovoltaic cell 23 among sheets, and it can also be set as an ion diffusion prevention layer. The film thickness of the ion diffusion preventing layer at this time is usually in the range of 0.1 to 10 μm, preferably in the range of 0.2 to 5 μm, and particularly preferably in the range of 0.5 to 2 μm. The application of magnesium oxide to the sealing sheet can be performed by the same method as the first embodiment described above.

  In the present embodiment, unlike the first embodiment, since the sealing material 24 also serves as the ion diffusion preventing layer, it is not necessary to apply the ion diffusion preventing layer as in the first embodiment, and the solar cell module The manufacturing cost of 20 can be reduced. Further, unlike the first embodiment, in the present embodiment, since there is no ion diffusion preventing layer between the light transmitting substrate 11 and the sealing material 14, the adhesion between the light transmitting substrate 21 and the sealing material 24 is obtained. The nature is not inhibited by the ion diffusion preventing layer, and the adhesion between the two is improved.

3. Third Embodiment In the first embodiment described above, the ion diffusion preventing layer 15 is disposed at the interface between the light transmitting substrate 11 and the sealing material 14, but as the ion diffusion preventing layer 15, It is not limited and may be disposed at the interface between the sealing material 14 and the solar battery cell 13. Hereinafter, a third embodiment of the present invention will be described.

  FIG. 3 is a schematic view showing a solar cell module according to a third embodiment of the present invention. As shown to this figure, the solar cell module 30 is provided with the translucent board | substrate 31, the back sheet 32, the photovoltaic cell 33, the sealing material 34, and the ion diffusion prevention layer 35. As shown in FIG. The light transmitting substrate 31 can adopt the same structure as the light transmitting substrate 11 of the first embodiment, the back sheet 32 the back sheet 12, and the solar cells 33 the solar cells 13, so The detailed explanation is omitted here.

  The ion diffusion prevention layer 35 of the present embodiment is provided between the solar battery cell 33 and the sealing material 34. In the figure, the ion diffusion preventing layer 35 covers the entire solar battery cell 33, but as the ion diffusion preventing layer 35 of the present invention, it covers at least the surface of the solar battery cell 33 on the translucent substrate 31 side. For example, diffusion of ions from the translucent substrate 31 to the solar battery cell 33 can be prevented.

  As described above, since the ion diffusion preventing layer 35 containing magnesium oxide covers the surface of the solar cell 33, the ion diffusion preventing layer 35 is passivated (deactivated) particularly when the solar cell 33 is silicon-based. It has the function as a layer. Here, the passivation layer is a layer having a function of improving the photoelectric conversion efficiency of the solar battery cell 33 by suppressing the recombination of carriers on the surface of the solar battery cell 33.

  The solar cell module 30 of the present embodiment is manufactured by applying magnesium oxide on the surface of the solar cell 33 to form the ion diffusion preventing layer 35 and thereafter sealing the solar cell 33 with the sealing material 34. be able to. The film thickness of the ion diffusion preventing layer 35 is usually in the range of 0.1 to 10 μm, preferably in the range of 0.2 to 5 μm, and particularly preferably in the range of 0.5 to 2 μm. The application of magnesium oxide to the solar battery cell 33 can be performed by the same method as the first embodiment described above.

  In the present embodiment, since the ion diffusion preventing layer 35 covers the solar battery cell 33, the ion diffusion from the light transmitting substrate 31 to the solar battery cell 33 is prevented, and the surface of the solar battery cell 33 is electrically Inactivation can be performed.

  Hereinafter, the present invention will be specifically described based on examples, but these do not limit the object of the present invention, and the present invention is not limited to these examples.

1. Example 1
(1) Component members of solar cell module The following members were used to constitute the solar cell module.
Translucent substrate: white sheet glass (single-sided embossing: white sheet template heat treated glass manufactured by Nakajima Glass Industry Co., Ltd.)
Back sheet: back sheet (PET base: SFC SPE-35)
Solar cell: Polycrystalline silicon cell (MOTEC IM156B3)
-Sealing material: Sealing sheet (product made from EVA: JH-40 NF made from JINHEUNG)

(2) Formation of an ion diffusion preventing layer on a glass substrate A dispersion liquid of magnesium oxide powder (average particle diameter 10 nm) prepared by oxidizing metal magnesium vapor using methanol as a solvent so as to have a concentration of 2.5 wt% Was prepared. Next, a dispersion was formed into a film on a white sheet glass using a spin coater (rotation speed: 100 rpm), and then dried at 120 ° C. to evaporate the solvent. The film thickness was measured by cross-sectional observation by SEM.

(3) Preparation of Sample A polycrystalline silicon solar cell was set between two sealing sheets, and this was further set between the white sheet glass on the light receiving surface side and the back sheet on the back surface side. After laminating this using a vacuum laminator, it was attached to an aluminum frame to make a sample of a solar cell module.

(4) PID evaluation test About the solar cell module using the photovoltaic cell of a polycrystal silicon system, the PID generation confirmation test accompanying time progress was done. First, the IV characteristic test before a test was implemented on the conditions of 25 degreeC-50% RH. Next, the sample was placed in a constant temperature and humidity chamber set at 85 ° C. and 85% RH. After reaching the set temperature and humidity conditions, the shorted output terminal was connected to the negative pole, and the aluminum frame was connected to the positive pole, and a voltage application of -1000 V was started. After 24 hours, a sample was taken out and an IV characterization test was performed. Again, after setting the sample in the constant temperature and humidity chamber and reaching the set conditions, the voltage application of 1000 V was started to restart the test. After 24 hours after reopening, the sample was taken out and an IV characterization test was performed. The maximum output was calculated from the obtained IV characteristics. The retention rates were also calculated by dividing the output after 24 hours and after 48 hours by the initial output, respectively. The obtained results are shown in Table 1.

2. Example 2
The sample was prepared in the same manner as in Example 1 except that the concentration of the magnesium oxide dispersion was 5 wt% and the film thickness was 1 μm, and a PID evaluation test was performed. The obtained results are shown in Table 1.

3. Example 3
The sample was prepared in the same manner as in Example 1 except that the concentration of the magnesium oxide dispersion was 10 wt% and the film thickness was 2 μm, and a PID evaluation test was performed. The obtained results are shown in Table 1.

4. Comparative Example 1
In Example 1, a sample was prepared without forming an ion diffusion prevention layer on white sheet glass, and a PID evaluation test was conducted. The obtained results are shown in Table 1.

5. Comparative example 2
In the dispersion of Example 1, isopropanol was used as a solvent, and the titanium oxide powder (average particle diameter 13 nm) was adjusted to a concentration of 5 wt%. When a dispersion was formed into a film on white sheet glass and the film thickness was measured in the same manner as in Example 1, it was 1 μm. A sample was prepared in the same manner as in Example 1 to conduct a PID evaluation test. The obtained results are shown in Table 1.

6. Comparative example 3
In Example 1, isopropanol was used as a solvent, and the zirconium oxide powder (average particle diameter 12 nm) was adjusted to a concentration of 10 wt%. When a dispersion was formed into a film on white sheet glass and the film thickness was measured in the same manner as in Example 1, it was 1 μm. A sample was prepared in the same manner as in Example 1 to conduct a PID evaluation test. The obtained results are shown in Table 1.

  Comparing Examples 1 to 3 having the ion diffusion prevention layer with Comparative Example 1 not having the ion diffusion prevention layer, Examples 1 to 3 having the ion diffusion prevention layer were after 24 hours and after 48 hours. It can be seen that the output retention rate is high. In addition, comparing Examples 1 to 3 using magnesium oxide with Comparative Example 2 using titanium oxide, the output retention ratio after 48 hours is higher in Examples 1 to 3 using magnesium oxide. Recognize. Furthermore, comparing Examples 1 to 3 using magnesium oxide with Comparative Example 3 using zirconium oxide, it can be seen that the initial output value is higher in Examples 1 to 3 using magnesium oxide.

  As described above, by including magnesium oxide in the ion diffusion preventing layer, the initial output value is high as compared to the case where other metal oxides are included, and the output is held for a long period of time (suppression of output decrease due to PID) It turned out that I could do it.

  In comparison with Examples 1 to 3, Example 2 having a film thickness of 1 μm has a higher output retention after 48 hours and a film thickness of 1 μm than Example 1 having a film thickness of 0.5 μm. It can be seen that the output retention rate after 48 hours is higher in Example 3 with a film thickness of 2 μm than in Example 2. Therefore, it was found that the film thickness of the ion diffusion preventing layer is preferably 1 μm or more, and about 2 μm is most preferable.

DESCRIPTION OF SYMBOLS 10 solar cell module, 11 translucent substrate, 12 back sheet, 13 solar cell, 14 sealing material, 15 ion diffusion prevention layer, 20 solar cell module, 21 translucent substrate, 22 back sheet, 23 solar cell , 24 sealing material (ion diffusion preventing layer), 30 solar battery module, 31 light transmitting substrate, 32 back sheet, 33 solar battery cell, 34 sealing material, 35 ion diffusion preventing layer

Claims (6)

Solar cells that convert incident light into electricity;
A translucent substrate located on the incident light side of the solar battery cell and containing or generating alkali metal ions;
And an ion diffusion preventing layer disposed between the light transmitting substrate and the solar battery cell to prevent the diffusion of the ions from the light transmitting substrate to the solar battery cell,
The ion diffusion preventing layer, having an average particle size magnesium oxide powder of 1 to 500 nm, the ion diffusion preventing layer, a solar cell module which is characterized that you have been disposed on the surface of the solar cell.   The solar cell module according to claim 1, wherein the ion diffusion preventing layer is a film body in which the magnesium oxide powder is laminated to have a film thickness of 0.1 to 10 μm.   The solar cell is sealed in a sealing material, The said ion diffusion prevention layer is arrange | positioned by the interface of the said translucent board | substrate and the said sealing material, It is characterized by the above-mentioned. The solar cell module of description. A method of manufacturing a solar cell module, comprising: a solar battery cell for converting incident light into electricity; and a light transmitting substrate containing or generating alkali metal ions,
Applying a dispersion comprising a solvent in which magnesium oxide powder having an average particle diameter of 1 to 500 nm is dispersed on one or both of the one surface of the light-transmissive substrate and the other surface of the solar battery cell;
In Runomi evaporating the solvent, to either or both of the other surface of the one surface of the transparent substrate wherein the solar cell, the ion diffusion preventing layer to form a magnesium oxide film containing the magnesium oxide powder Forming process,
See containing and a placement step of placing the other surface and the translucent substrate to face is the solar cell and a surface of the translucent substrate and the solar cells,
A method of manufacturing a solar cell module, comprising forming an ion diffusion preventing layer without passing through the step of densifying the magnesium oxide film . A method of manufacturing a solar cell module, comprising: a solar battery cell that converts incident light into electricity; and a translucent substrate that contains or generates alkali metal ions,
A sealing step of sealing the solar battery cell with a sealing material;
Applying a dispersion liquid comprising a solvent in which magnesium oxide powder having an average particle diameter of 1 to 500 nm is dispersed on the surface of the sealing material facing the light transmitting substrate;
In Runomi evaporating the solvent, the surface of the sealing material, and an ion diffusion preventing layer forming step of forming a magnesium oxide film containing the magnesium oxide powder,
See containing and a placement step of placing the said and the transparent substrate sandwiching the magnesium oxide film and the solar cell and the transparent substrate so as to face the solar cell,
A method of manufacturing a solar cell module, comprising forming an ion diffusion preventing layer without passing through the step of densifying the magnesium oxide film . The method for manufacturing a solar cell module according to claim 4 or 5 , wherein the dispersion is applied in the application step such that the thickness of the magnesium oxide film is 0.1 to 10 μm.

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