JP2006261262A - Solar cell module with frame and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low cost solar cell module with a frame. <P>SOLUTION: In the solar cell module with a frame, the light receiving surface side of a solar cell element 1 is sealed with a sealing material 3 and a light transmitting member 2 in the external side thereof, and a frame 5 is provided to the external circumference of the solar cell element sealing material where the rear surface side is sealed with the sealing material 3 and a back sheet 4 in the external side thereof. In the solar cell module, the frame is fixed to the solar cell element sealing material by bonding the back sheet formed of a thermosetting resin to the frame. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a solar cell module, and more particularly to a solar cell module with a frame in which a frame body is provided on an outer peripheral portion.

  FIG. 2 is a schematic cross-sectional view showing the basic structure of a framed solar cell module. In FIG. 2, 1 is a solar cell element, 3 is a sealing material, 2 is a translucent member, 4 is a back sheet, and 5 is a frame. Sunlight passes through the translucent member and the sealing material, enters the light receiving surface of the solar cell element, and is converted into electric energy. The generated electricity is taken out from an output terminal (not shown).

  The frame body is formed by fitting a groove provided in the frame body to a solar cell element sealing body in which the solar cell element is sealed with a sealing material, a translucent member, and a back sheet. Placed in the department. At that time, since the fixing between the frame body and the solar cell element sealing body is insufficient only by fitting, the sealing material 7 is fixed by a method such as insertion between the frame body and the solar cell element sealing body. Has been done.

  For example, in Patent Document 1, a rubber for sealing insulation is interposed between the frame body and the solar cell element sealing body, and in Patent Document 2, butyl rubber is interposed between the frame body and the solar cell element sealing body. Is disclosed. Patent Document 3 discloses a method of forming a frame body by integral molding of urethane resin. In this case, the frame body is directly bonded and fixed to the solar cell element sealing body.

  Furthermore, the frame body and the solar cell element sealing body are widely bonded and fixed with a one-component curable silicone sealant.

Patent No. 3337286 JP-A-11-121781 Japanese Patent Laid-Open No. 11-97731

  However, when fixing with an adhesive such as silicone sealant, it takes time for the adhesive to harden, so the solar cell module must be stocked for a long time in the production process, and it is difficult to automate the application of the adhesive, etc. For this reason, it has been an obstacle to reducing the manufacturing cost. If a rubber member such as butyl rubber is used instead of the adhesive, the problem of the curing time can be solved, but automation is similarly difficult, and the rubber material is relatively expensive in terms of reducing the manufacturing cost. It becomes a problem.

  On the other hand, the method of forming a frame body by integral molding of resin is relatively easy to automate, and can be said to be a method suitable for cost reduction because it does not require an adhesive or a rubber member. In addition to the aluminum frame that has been used in the past in terms of long-term reliability outdoors, the solar cell module using the conventional aluminum frame is the installation method of the solar cell module In contrast, it has a problem that it is difficult to maintain installation compatibility.

  As a result of intensive research and development to solve the above problems, the present inventor has found that the following method is the best.

That is, in the invention of claim 1 for solving the above problem, the light receiving surface side of the solar cell element is sealed with the sealing material and the translucent member outside thereof, and the back surface side is sealed with the sealing material and the outside thereof. In a solar cell module with a frame in which a frame body is provided on the outer periphery of a sealed solar cell element that is sealed with a back sheet, the frame body is formed by directly bonding the back sheet made of thermoplastic resin to the frame body. Is fixed to the sealed solar cell element.
The invention of claim 2 is characterized in that a melting point of the thermoplastic resin is higher than a melting point of the sealing material.
The invention of claim 3 is characterized in that the thermoplastic resin is an ionomer resin.

The invention of claim 4 for solving the above problem is a method for manufacturing a solar cell module with a frame, wherein the light receiving surface side of the solar cell element is sealed with a sealing material and a translucent member on the outside thereof. A step of forming a sealed solar cell element that seals the back side with a sealing material and a back sheet on the outside, a step of fitting the sealed solar cell element to the frame, and a frame The method includes a step of directly bonding the frame and the back sheet by heating and melting the back sheet made of the thermoplastic resin.
Further, in the invention of claim 5, the forming step of the sealing body is performed by a vacuum heating laminating method, and the melting point of the thermoplastic resin is made higher than the melting point of the sealing material, whereby the vacuum heating laminating method is performed. The fluidity of the thermoplastic resin at the upper limit temperature is lower than the fluidity of the sealing material.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide a solar cell module with a frame at low cost. That is, an adhesive and a rubber member for adhering and fixing the frame body and the solar cell element sealing body are not required, the time required for adhesion of the frame body is shortened, and further automation is facilitated, thereby reducing the manufacturing cost. Can be reduced. Moreover, since the frame used conventionally is not changed, a product compatible with the conventional solar cell module with a frame can be manufactured at low cost.

  In particular, when the melting point of the thermoplastic resin is higher than the melting point of the sealing material, the sealing performance of the back surface of the solar cell element is improved. That is, when the solar cell element is sealed by thermocompression bonding, the back sheet is not significantly melted compared to the sealing material, and the fluidity can be made lower than that of the sealing material. As a result, the encapsulant flows sufficiently to seal the solar cell element, while ensuring the thickness of the back sheet without impairing the performance as the back sheet, for example, the covering property and the electrical insulation.

  In particular, since the thermoplastic resin is an ionomer resin, the adhesion between the frame body and the solar cell element sealing body, and the long-term durability, electrical insulation, and waterproofness, which are performances required as a back sheet, are high. It becomes possible to satisfy with the level.

  FIG. 1 shows an example of a schematic sectional view of a solar cell module with a frame of the present invention. In FIG. 1, 1 is a solar cell element, 2 is a translucent member, 3 is a sealing material, 4 is a back sheet, and 5 is a frame.

  The back sheet and the frame in the present invention will be described in detail below.

  The back sheet 4 is used to protect the solar cell element, prevent moisture from entering, and maintain electrical insulation from the outside. As a material, a material that can ensure sufficient electrical insulation, has excellent long-term durability, and can withstand thermal expansion and contraction is preferable. Furthermore, in this invention, adhesiveness with a frame is requested | required. Preferred examples include ethylene-vinyl acetate copolymer (EVA) resin, ethylene-methyl acrylate copolymer (EMA) resin, ethylene-ethyl acrylate copolymer (EEA) resin, ethylene-acrylic acid. Examples thereof include thermoplastic resins such as butyl copolymer (EBA) resin, ethylene-methacrylic acid copolymer (EMAA) resin, ionomer resin, polyester resin, urethane resin, acrylic resin, polyethylene resin, polypropylene resin, and polyamide resin. Among these, ionomer resins have excellent adhesion to aluminum, which is a common material for frames, and weather resistance, heat resistance, cold resistance, water resistance, impact resistance, wear resistance, scratch resistance, electrical insulation, etc. Since it has the balanced physical property as a back seat | sheet of a solar cell module, it is used especially suitably.

  In order to prevent the back sheet from melting and flowing during sealing of the solar cell element described later, the melting point of the thermoplastic resin used as the back sheet is preferably higher than the melting point of the sealing material.

  When moisture resistance is required for the back sheet, an aluminum foil, an aluminum vapor-deposited film, a silicon oxide vapor-deposited film or the like may be laminated on the solar cell element side of the back sheet.

  The frame body 5 is provided with a U-shaped groove so as to be fitted to the outer peripheral portion of the solar cell element sealing body, and the frame body and the back sheet are bonded inside the groove. An adhesion location is not specifically limited, It determines according to the heating conditions of the frame in the melt | fusion process of the backsheet mentioned later.

  The material of the frame is not particularly limited, but aluminum is generally used in consideration of strength and corrosion resistance. When the material is aluminum, the surface is anodized as necessary.

  Hereinafter, each member which comprises a solar cell module is demonstrated.

  As the solar cell element 1, 1) a crystalline silicon solar cell, 2) a polycrystalline silicon solar cell, 3) a microcrystalline silicon solar cell, 4) an amorphous silicon solar cell, 5) a copper indium selenide solar cell, 6) a compound semiconductor Various conventionally known elements such as solar cells may be selected and used according to the purpose. A plurality of these solar cell elements are connected in series or in parallel according to a desired voltage or current. Alternatively, a desired voltage or current can be obtained by integrating solar cell elements on an insulated substrate. Further, a bypass diode is connected to the element as necessary in order to prevent reverse bias application to the element.

  Since the translucent member 2 is located on the outermost layer of the solar cell module, it requires performance for ensuring long-term reliability in outdoor exposure of the solar cell module, including weather resistance, contamination resistance, and mechanical strength. Examples of the member suitably used in the present invention include a (reinforced) glass plate and a fluoride polymer film. As the glass plate, it is preferable to use white plate glass having a high light transmittance. Specific examples of the fluoride polymer film include tetrafluoroethylene-ethylene copolymer (ETFE), polyvinyl fluoride resin (PVF), polyvinylidene fluoride resin (PVDF), polytetrafluoroethylene resin (TFE), There are tetrafluoroethylene-hexafluoropropylene copolymer (FEP) and polytrifluoroethylene chloride (CTFE). Polyvinylidene fluoride resin is excellent in terms of weather resistance, but tetrafluoroethylene-ethylene copolymer is excellent in terms of both weather resistance and mechanical strength. In order to improve the adhesion between the fluoride polymer film and the sealing material, it is desirable to perform corona treatment and plasma treatment on the film. It is also possible to use a film that has been subjected to a stretching treatment in order to improve mechanical strength.

  The sealing material 3 is necessary for covering the unevenness on the surface of the solar cell element with a resin and protecting the element from the external environment. It also plays a role of adhering a translucent member and a back sheet to the element. Therefore, in addition to high transparency, weather resistance, adhesiveness, and heat resistance are required. Materials satisfying such requirements include ethylene-vinyl acetate copolymer (EVA) resin, ethylene-methyl acrylate copolymer (EMA) resin, ethylene-ethyl acrylate copolymer (EEA) resin, ethylene- Examples include methacrylic acid copolymer (EMAA) resin, ionomer resin, polyvinyl butyral resin, and the like. Above all, EVA resin is suitably used because it has well-balanced physical properties for solar cell applications such as weather resistance, adhesiveness, filling property, heat resistance, cold resistance, and impact resistance.

  Next, a method for producing a framed solar cell module using the back sheet, frame, solar cell element, translucent member, and sealing material described above will be described.

  First, the sealing material shape | molded in the sheet form is distribute | arranged to the light-receiving surface side and back surface side of a solar cell element, respectively. Furthermore, it is set as the laminated body which has arrange | positioned the translucent member and the back sheet | seat on the light-receiving surface side and back surface side, respectively. A solar cell element sealed body can be obtained by thermocompression bonding this under reduced pressure using a vacuum laminator. In addition, it is possible to produce a sealing body by roll lamination or the like.

  Next, after the groove portion of the frame body is fitted to the outer peripheral portion of the solar cell element sealing body, the frame body and the back sheet are bonded by locally heating the fitting portion to melt the back sheet. To do. Examples of the heating method include a hot air method in which high-temperature air supplied from a nozzle is applied to an object to be heated, and a method in which heating is performed by bringing an infrared heater close to the object, but the hot air method is uniformly heated with a simple device. This is preferable. Moreover, in order to heat more efficiently, you may heat a frame beforehand.

  Hereinafter, the solar cell module with a frame of the present invention will be described in detail based on examples. In addition, this invention is not limited to the following Examples at all, and can be variously changed within the range of the summary.

Example 1
A method for producing a framed solar cell module of the present invention will be described below with reference to FIG.

  A plurality of solar cell elements 1 are connected in series to form a solar cell element serial body 8, and an output extraction electrode made of copper foil is attached to an electrode provided in the solar cell element at the end of the series.

  Next, a sealing material, a translucent member, and a back sheet for sealing the solar cell element serial body 8 will be described.

  In the sealing material 3, an ethylene-vinyl acetate copolymer (EVA) resin (JIS K7121) whose durability is improved by adding a crosslinking agent, a silane coupling agent, an ultraviolet absorber, a light stabilizer, and an antioxidant. And a 400 μm thick sheet (hereinafter referred to as EVA sheet).

  The translucent member 2 is made of white plate tempered glass having a thickness of 3.2 mm.

  As the back sheet 4, a sheet having a thickness of 100 μm made of an ionomer resin (melting point: 96 ° C. according to JIS K7121) whose durability is improved by adding an ultraviolet absorber, a light stabilizer, and an antioxidant is used.

  The series of solar cell elements is laminated with an EVA sheet, glass, and back sheet. That is, a solar cell element is formed by stacking an EVA sheet and glass on the light-receiving surface side of the series of solar cell elements and laminating an EVA sheet and a back sheet on the back surface side, and thermocompression bonding at 150 ° C. for 30 minutes with a vacuum laminator. Is sealed.

  An output extraction electrode (not shown) is led out from an opening provided in advance in the back surface sealing EVA sheet and the back sheet.

  The groove portion of the frame body 5 made of aluminum is fitted to the outer peripheral portion of the solar cell element sealing body manufactured in this way, and hot air of about 500 ° C. supplied from a plurality of nozzles is applied to a portion 6 where the frame body and the back sheet are in contact with each other. The frame and the back sheet are bonded by melting the back sheet for 1 minute to obtain a solar cell module with a frame.

  About the solar cell module with a frame obtained in this way, the following items were evaluated.

(1) Humidity resistance test The framed solar cell module was placed in an atmosphere of 85 ° C./85% RH for 1000 hours, and changes in appearance after the test were observed.

(2) Temperature cycle test -40 ° C / 30 minutes, 90 ° C / 5 hours, 200 cycles of a temperature cycle test at a temperature change rate of 120 ° C / hour between -40 ° C and 90 ° C, and the appearance after the test Changes were observed.

(Example 2)
In Example 1, as a back sheet, an ethylene-methacrylic acid copolymer (EMAA) resin (melting point 94 ° C. according to JIS K7121) whose durability was improved by adding an ultraviolet absorber, a light stabilizer, and an antioxidant. A sheet having a thickness of 100 μm is used. Moreover, before fitting a frame to a solar cell sealing body, it heats to 80 degreeC beforehand and sets the time which applies hot air to 30 second. Otherwise, a framed solar cell module was prepared and evaluated in the same manner as in Example 1.

  In the solar cell module with a frame produced in Examples 1 and 2, no change in appearance was observed in either the moisture resistance test or the temperature cycle test, and the frame body was a solar cell element sealed body even after the test. It was fixed with sufficient strength.

  In addition, the time required for bonding and fixing the frame body to the sealed solar cell element is about one minute, which is much shorter than the process using the conventional adhesive, and preheating the frame body as in the second embodiment. As a result, it was found that the process can be further shortened. On the other hand, since the application process to the fitting part of the adhesive and the insertion process to the fitting part of the rubber member are not required, the manufacturing process is simplified and automation is facilitated. As a result, the manufacturing cost of the framed solar cell module can be significantly reduced.

It is a schematic sectional drawing of one Embodiment of the solar cell module with a frame of this invention. It is a schematic sectional drawing which shows an example of the conventional solar cell module with a frame.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solar cell element 2 Translucent member 3 Sealing material 4 Back sheet 5 Frame body 6 Adhesive part of a frame body and a solar cell element sealing body 7 Seal material 8 Solar cell element serial body

Claims (5)

  The solar cell element sealing body in which the light-receiving surface side of the solar cell element is sealed with a sealing material and a translucent member outside thereof, and the back surface side is sealed with the sealing material and a back sheet outside thereof. In a solar cell module with a frame in which a frame body is provided on the outer periphery, the frame body is fixed to the solar cell element sealing body by directly bonding a back sheet made of a thermoplastic resin to the frame body. A solar cell module with a frame.   The framed solar cell module according to claim 1, wherein a melting point of the thermoplastic resin is higher than a melting point of the sealing material.   The framed solar cell module according to claim 1 or 2, wherein the thermoplastic resin is an ionomer resin.   Formation of a solar cell element sealing body in which a light receiving surface side of a solar cell element is sealed with a sealing material and a translucent member outside thereof, and a back surface side is sealed with a sealing material and a back sheet outside thereof. Including a step, a step of fitting the solar cell element sealing body to the frame, and a step of heating the frame to melt the back sheet made of a thermoplastic resin and directly bonding the frame and the back sheet. A method for producing a framed solar cell module.   The step of forming the sealing body is performed by a vacuum heating laminating method, and by making the melting point of the thermoplastic resin higher than the melting point of the sealing material, the thermoplastic resin at the upper limit temperature of the vacuum heating laminating method is formed. The method for producing a framed solar cell module according to claim 4, wherein the fluidity is lower than the fluidity of the sealing material.

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