JP2008091620A - Solar cell module, solar cell panel, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solar cell module whose structure is simplified, a solar cell panel, and a manufacturing method thereof. <P>SOLUTION: The solar cell module includes a substrate, a solar cell film prepared on the substrate, and a bus bar, wherein the solar cell film is divided into a plurality of reed-shaped power generating cells, the plurality of power generating cells is electrically connected in series, the bus bar is electrically prepared to the each of the power generating cell of the both ends, and the bus bar is made to be a calcinated electrode obtained by calcinating a paste raw material containing conductive substance. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a solar cell module, a solar cell panel, and a manufacturing method thereof.

  A solar power generation system that generates power using sunlight and uses the power is known. The solar power generation system is usually installed outdoors. The solar power generation system is configured by electrically connecting a plurality of solar battery panels. Fig.1 (a) is a top view of the conventional solar cell panel, FIG.1 (b) is sectional drawing along the AA line of (a). As shown in FIG. 1, each solar cell panel has a solar cell module and a frame having a U-shaped cross section attached to an end of the solar cell module. The solar cell panel is fixed to the ground or the roof by supporting the frame portion with a column or the like (not shown).

  By the way, as a material of the frame, a metal material such as aluminum is mainly used in terms of strength and the like. Solar cell panels are used outdoors for a long time. It is assumed that the solar cell panel is exposed to an environment such as snow and rain after long-term use. If moisture accumulates between the solar cell module and the metal frame due to snow or rain, the solar cell module may be short-circuited (ground fault) to the ground through the moisture. In order to prevent such a ground fault, the structure of the frame is required to be a structure in which water does not accumulate. That is, the frame structure requires a specially designed structure for draining water. In addition, in order to eliminate the influence of water, it has been necessary to devise measures such as sealing the end of the solar cell module. In addition, when the snow is piled up, the solar cell module may be detached from the frame due to the weight of the snow.

  On the other hand, the structure of the solar cell module itself is also complicated. Fig.2 (a) is a top view which shows the back surface structure of the solar cell module. FIG. 2B is a cross-sectional view taken along line BB in FIG. In FIG. 2A, the internal structure is actually covered with a protective material or the like and cannot be seen, but for the sake of convenience of explanation, a part thereof is shown through. The solar cell module has a structure in which a solar cell film is formed on a substrate. The solar cell film is usually divided into a plurality of power generation cells. The plurality of power generation cells are electrically connected in series. The electric power generated by solar power is electrically extracted from the power generation cells at both ends. Bus bars are connected to the power generation cells at both ends in order to suppress resistance during current collection. As the bus bar, copper foil is usually used. Further, in order to extract electric power from the bus bar to the outside, an extraction wiring is provided. A protective material is disposed on these members in order to prevent a short circuit with the outside and infiltration of moisture. The protective material is provided with an opening for drawing out the extraction wiring to the outside. Usually, there is one opening. Therefore, each extraction wiring is extended from the bus bar to its opening so as to straddle the solar cell film. Copper foil is used as the extraction wiring. In order to prevent a short circuit, an insulating sheet (not shown) is arranged between the extraction wiring and the solar cell film.

  In order to prevent moisture from entering in the opening provided in the protective material, for example, a special waterproof structure such as arranging a large number of sheet materials between the extraction wiring and the solar cell film is required.

  Further, as the protective material covering the solar cell film, since it is required to reliably prevent moisture from entering, a sheet material of a plurality of layers including a metal sheet is used instead of a single layer. Such a sheet material is affixed on a solar cell film | membrane through adhesives, such as EVA (ethylene vinyl acetate copolymer). In relation to this, Patent Document 1 describes that a metal sheet sandwiched between PET sheets is used as the protective material sheet.

  However, when a metal sheet is used, the electrostatic capacity of the solar cell panel may increase. A solar cell panel may incorporate a device for detecting a ground fault current. Due to the increase in the capacitance of the solar cell panel, this ground fault current detection device may be erroneously detected.

  Moreover, when arrange | positioning copper foil as a bus-bar or extraction wiring, copper foil may shift | deviated from the predetermined place. In such a case, since the copper foil has to be rearranged, the number of processes has been increased.

  In relation to the above, Patent Document 2 describes a bus bar. Patent Document 1 describes that after partially removing a semiconductor layer and a back electrode layer, a current collecting bus bar using a copper foil is soldered to a transparent conductive layer.

  Patent Document 3 describes a protective material. Patent Document 2 describes that in a solar cell module in which a solar cell element is housed and sealed inside by a surface support and a back surface protection sheet, the back surface protection sheet is composed of a single layer of polychlorotrifluoroethylene sheet. Has been.

  Patent Document 4 describes that a copper foil and an insulating film are used to lay up while performing wiring inside the solar cell panel.

However, if the complicated configuration as described above is used, an increase in manufacturing steps and a difficulty in manufacturing increase, which contributes to an increase in manufacturing cost.
JP-A-2005-236051 JP 2000-49369 A JP 2001-127320 A Japanese Patent Laid-Open No. 2002-111022

That is, an object of the present invention is to provide a solar cell module, a solar cell panel, and a method for manufacturing the same, with a simplified structure.
Another object of the present invention is to provide a solar cell module, a solar cell panel, and a method for manufacturing the same, in which moisture is prevented from entering.
Still another object of the present invention is to provide a solar cell module, a solar cell panel, and a manufacturing method thereof in which erroneous detection of a ground fault current is prevented.

  Means for solving the problem is expressed as follows. Technical matters appearing in the expression are appended with numbers, symbols, etc. in parentheses. The numbers, symbols, and the like are technical matters constituting at least one embodiment or a plurality of embodiments of the present invention or a plurality of embodiments, in particular, the embodiments or examples. This corresponds to the reference numbers, reference symbols, and the like attached to the technical matters expressed in the drawings corresponding to. Such reference numbers and reference symbols clarify the correspondence and bridging between the technical matters described in the claims and the technical matters of the embodiments or examples. Such correspondence or bridging does not mean that the technical matters described in the claims are interpreted as being limited to the technical matters of the embodiments or examples.

  The solar cell module (20) according to the present invention includes a substrate (1), a solar cell film (40) provided on the substrate (1), a bus bar (3), and a take-out connected to the bus bar (3). And a terminal box (12) for storing the wiring for use. The solar cell film (40) is divided into a plurality of strip-shaped power generation cells (9). The plurality of power generation cells (9) are electrically connected in series. The bus bar (3) is electrically connected to each of the power generation cells (9) at both ends. The bus bar (3) is a fired electrode obtained by firing a paste-like raw material containing a conductive material.

  Thus, since the fired electrode is used as a bus bar, a copper foil as a bus bar is not necessary. Therefore, it becomes a simpler structure and the fear of the position shift at the time of arrange | positioning copper foil as a bus-bar is eliminated.

  The solar cell module (20) preferably further includes an extraction portion (10) provided corresponding to each of the bus bars (3). The take-out part (10) is provided on the bus bar (3) and wired so that electric power is taken out from the bus bar (3) through the take-out part (10).

  In such a configuration, in order to extract electric power from the bus bar to the outside, it is not necessary to arrange the extraction wiring (copper foil) on the solar cell film via the insulating sheet. Therefore, the fear of the position shift at the time of disposing the extraction wiring and the insulating sheet on the solar cell film is also eliminated. Moreover, since the bus bar is provided in the vicinity of the end of the solar cell module, it is easy to take out the cable for external connection from the side of the solar cell panel. The workability at the time of connecting solar cell panels improves by taking out a cable from a solar cell panel side part.

In the solar cell module (20), the firing electrode comprises a Ag and SiO _2, the main component of the sintered electrode is preferably Ag.
By including SiO ₂ , the surface area of the base is increased and the adhesive force is improved. Further, by using Ag as a main component, it is easy to perform soldering when connecting the wiring to the bus bar.

  In the solar cell module (20), the solar cell film (40) includes a transparent conductive layer (2), a photoelectric conversion layer (5), and a back electrode layer (6), and the bus bar (3) It is preferably provided on the transparent conductive layer (2).

An insulating film may be provided as an alkali barrier film between the transparent conductive layer and the substrate. In this case, if the bus bar is provided between the transparent conductive layer and the substrate, wiring from the bus bar to the outside of the solar cell module cannot be performed.
On the other hand, when a bus bar is provided on the photoelectric conversion layer or the back electrode layer, the photoelectric conversion layer or the back electrode layer is exposed to a high temperature state during firing. The photoelectric conversion layer and the back electrode layer cause deterioration during firing.
When the bus bar is provided on the transparent conductive layer, wiring from the bus bar to the outside of the solar cell module can be performed, and the photoelectric conversion layer and the back electrode layer are not deteriorated during firing.

  In said solar cell module (20), it is preferable that the thickness of a bus-bar (3) is 15 micrometers or more-50 micrometers or less.

  When the thickness of the bus bar is less than 15 μm, the resistance of the bus bar increases, and the electric power generated by the solar cell film may not be taken out efficiently. On the other hand, when trying to make it thicker than 50 μm, when applying the raw material of the bus bar, the applied liquid spreads too much and it becomes difficult to provide the bus bar at a predetermined position.

  The solar cell module further includes a back surface protective material (11) that covers the solar cell film (20), and the back surface protective material (11) is preferably a single sheet material. The back surface protective material (11) is more preferably a non-metallic sheet material, and particularly preferably a sheet material mainly composed of ethylene / propylene rubber.

The surface of the fired electrode has large irregularities. Therefore, when the back surface protective material having the same thickness is used, the single sheet material has better conformity to the unevenness than the laminated body, and the stress generated at the interface is easily relieved.
By using a single sheet material as the back surface protective material, the configuration is simplified. In addition, the number of man-hours can be reduced compared to using a plurality of stacked sheets.
In addition, since the back surface protective material is a non-metallic sheet material, the capacitance of the solar cell panel increases as in the case where the metal sheet is sandwiched between PET sheets, leading to false detection of ground fault current. There is nothing.

  A solar cell panel (30) according to the present invention includes the above-described solar cell module (20), a base (14) on which the solar cell module (20) is placed, and the solar cell module (20) as a base (14). And a plurality of fixing members (17) fixed to each other. The solar cell module (20) is fixed by a plurality of fixing members (17) at a plurality of fixing points. The number of the plurality of fixed points is a number determined by the strength examination according to the strength required for the strength of the solar cell module (20).

  Thus, if it is set as the structure which fixes a solar cell module by an appropriate number of several fixing points, since the frame is not used, it can prevent that a water | moisture content accumulates around a solar cell module. This prevents the solar cell module from being grounded with the ground through the accumulated moisture. Further, since the frame is not used, the solar cell module is not dropped from the frame due to snow or rain. Moreover, when installing a solar cell panel, since a solar cell module is only mounted and fixed to a base, workability | operativity is also favorable. Furthermore, by using a non-metallic base, material costs can be reduced as compared with the case of using an expensive metallic frame. Furthermore, since the base is made of a non-metal and has low conductivity, the occurrence of a ground fault current can be suppressed even when the solar cell module, the moisture, the base, and the ground are continuously formed by moisture.

  In the solar cell panel (30), the base (14) is preferably made of plastic from one viewpoint. The base (14) more preferably contains high-density polyethylene.

  Moreover, it is preferable that the base (14) is metal from another viewpoint, and it is more preferable that aluminum is included.

  The solar cell module manufacturing method according to the present invention includes a solar cell film forming step of forming a solar cell film (40) divided into a plurality of strip-shaped power generation cells (9) on a substrate (1), and a solar cell module. A bus bar forming step (step S20) for connecting the bus bar (3) and a terminal box (12) for storing wiring for extracting power from the bus bar (3) to the outside are formed on a part of the battery membrane (40). And a terminal box mounting step (step S110). The plurality of power generation cells (9) are electrically connected in series. In the bus bar forming step (S20), the bus bar (3) is formed so as to be electrically connected to the power generation cells (9) at both ends. The bus bar forming step (S20) includes a step of applying a paste-like raw material containing a conductive substance, and a baking step of baking the applied raw material to form a fired electrode. In the terminal box mounting step (S110), the terminal box (12) is mounted on both ends of the power generation cell (9) in the series connection direction on the substrate (1).

In the manufacturing method of the solar cell module described above, the fired electrode preferably contains Ag and SiO _2, and the main component of the fired electrode is preferably Ag.

  In the above solar cell module manufacturing method, the solar cell film forming step includes a transparent conductive layer forming step (step S10) for forming a transparent conductive layer (2) on the substrate (1), and a transparent conductive layer (2). A photoelectric conversion layer forming step (step S40) for forming the photoelectric conversion layer (5) on the substrate on which the photoelectric conversion layer is formed, and a back surface for forming the back electrode layer (6) on the substrate on which the photoelectric conversion layer (5) is formed. Electrode layer forming step (step S60). The bus bar forming step (S20) is preferably performed between the transparent conductive layer forming step (S10) and the photoelectric conversion layer forming step (S40).

  In the manufacturing method of the solar cell module, it is preferable that the baking process is performed at a temperature of 300 ° C. or higher and 500 ° C. or lower. When baking is performed at a temperature higher than 500 ° C., the transparent conductive layer 2 as a base may be corroded and peeled off. If firing is performed at a temperature lower than 300 ° C., the solvent in the paste is difficult to volatilize, and firing may take time.

  The method for manufacturing the solar cell module is further performed after the back electrode layer forming step (S60), and the back electrode layer (6) and the photoelectric conversion layer (5) are removed to remove at least one of the bus bars (3). It is preferable to include a bus bar exposing step (step S90) for exposing the portion.

  In the above solar cell module manufacturing method, the thickness of the bus bar (3) is preferably 15 μm to 50 μm.

  The method for manufacturing the solar cell module further includes a back surface protective material forming step (step S100) for covering the solar cell film (40) with the back surface protective material (11). One sheet material is preferable.

  In the above solar cell module manufacturing method, the back surface protective material (11) is preferably a sheet material mainly composed of ethylene / propylene rubber.

  The solar cell panel manufacturing method according to the present invention includes a step (step S140) of mounting the solar cell module (20) manufactured by the above-described solar cell module manufacturing method on the base (14). And a fixing step (step S150) for fixing the solar cell module (20) to the base (14) by a plurality of fixing members (17). In the fixing step (step S150), the solar cell module (20) is fixed by a plurality of fixing members (17) at a plurality of fixing points. The number of the plurality of fixed points is a number determined by the strength examination according to the strength required for the strength of the solar cell module (20).

  In the above solar cell panel manufacturing method, the base (14) is preferably made of plastic and more preferably contains high-density polyethylene from one viewpoint.

  In the above solar cell panel manufacturing method, the base (14) is preferably made of metal and more preferably contains aluminum from another viewpoint.

According to the present invention, there are provided a solar cell module, a solar cell panel, and a method for manufacturing the same, with a simplified structure.
According to the present invention, there are further provided a solar cell module, a solar cell panel, and a method for manufacturing the same, in which moisture is prevented from entering.
According to the present invention, there are further provided a solar cell module, a solar cell panel, and a manufacturing method thereof, in which erroneous detection of a ground fault current is prevented.

(First embodiment)
With reference to the drawings, the structure of the solar cell panel according to the first embodiment of the present invention will be described.

  FIG. 3 is a perspective view showing the structure of the solar cell panel 30. The solar cell panel 30 includes the solar cell module 20 and the base 14. The solar cell module 20 is placed on the base 14. The solar cell module 20 is fixed to the base 14 at a plurality of locations by fixing brackets 17 and screws 18.

  The position and number of locations (fixed points) where the fixing bracket 17 and the screw 18 are provided are determined by examining the strength according to the strength required for the strength of the solar cell module (20). The yield strength of the substrate varies depending on the number and position of the fixing points. The number and position of such fixed points can be calculated in advance by simulation. For example, when a glass float substrate with a thickness of 1.4 m × 1.1 m × 4 mm is used as the substrate, the fixed points can be set to 14 points or more in total, 4 on the long side and 3 on the short side. it can.

  As the fixing bracket 17, for example, one having an L-shaped cross section can be used. The fixing bracket 17 is provided with an opening for a screw 18. As the material of the fixing bracket 17 and the screw 18, a material having corrosion resistance is preferable. Examples of such a material include stainless steel.

  FIG. 4A is a perspective view showing the structure of the base 14. The base 14 is provided with two notches 16, a rib structure 13, and a helicate 15.

  The two notches 16 are provided at positions corresponding to the terminal box 12 when the solar cell module 20 is placed. Details of the terminal box 12 will be described later. When the solar cell module 20 is placed on the base 14, the terminal box 12 portion enters the notch 16. By providing the notches 16 in this way, the connection cable 21 can be taken out from the side of the base 14 when the solar cell module 20 is fixed to the base 14. The workability at the time of connecting solar cell panels improves by taking out the cable 21 for connection from a side part.

  The rib structure 13 is provided at the center of the base 14. The rib structure 13 is provided to improve the rigidity of the base 14. Moreover, it is preferable that the rib structure 13 part has a structure penetrating in the vertical direction. By penetrating vertically, water can be prevented from accumulating between the solar cell module 20 and the base. However, as shown in FIG. 4B, the rib structure 13 may be divided into a plurality of regions.

  A description will be given with reference to FIG. 4A again. The helisert 15 is a female screw having a shape corresponding to the screw 18. When the solar cell module 20 is fixed by the fixing bracket 17 and the screw 18, the screw 18 is fitted to the helicate 15.

  Examples of the material of the base 14 include a plastic material and a metal material. Examples of plastic materials include resin materials containing high-density polyethylene. A resin material containing high-density polyethylene is excellent in processability and can be processed into a desired structure. Moreover, since the thing made from a plastic is nonelectroconductive, even if a water | moisture content accumulate | stores around a solar cell module, possibility that a solar cell module will ground through water and a base can be reduced. That is, the occurrence of ground fault current is suppressed.

  As shown in FIG. 4B, when the size of the solar cell module is 1100 mm × 1400 mm, the thickness of the plastic base 14 is, for example, 30 mm. The size (pitch) of the through holes of the rib structure 13 is, for example, 50 mm.

  On the other hand, the metal one is excellent from the viewpoint of durability (weather resistance) and cost. As such a metal thing, the thing made from aluminum can be mentioned.

  Aluminum, for example, is used as a material for a frame having a U-shaped cross section shown in FIG. 1, and is known to be preferable from the viewpoint of durability. Moreover, when the present inventors examined, as shown in FIG. 1, rather than the case where the side part of a solar cell module is supported by a frame (frame) shape, the solar cell module is mounted using the base 14. In some cases, it was found that the support (frame or base) could be formed with a small amount of material. That is, if the aluminum base 14 is used, the material cost of the base 14 can be reduced as compared with the conventional aluminum frame shown in FIG.

  Further, when the base 14 is made of metal, it can be formed only by combining commercially available materials. Specifically, a frame shape may be made of aluminum squares, and a rib structure portion may be fitted into an inner portion of the frame shape. For example, as shown in FIG. 4C, the rib structure portion can be formed by combining flat plate members having notches in a lattice shape. As such a rib structure portion, for example, a member such as an aluminum louver LGA (trade name, manufactured by Hosei Co., Ltd.) can be used. The base 14 can be easily formed using a commercially available product. On the other hand, when a member having a U-shaped cross section as shown in FIG. 1 is processed into a frame shape, a special device may be required for the connection structure of the corners. By using the base 14 having the rib structure 13, the base 14 can be easily formed using a commercially available product, which is advantageous from the viewpoint of processing costs.

  The structure of the solar cell module 20 will be described with reference to FIGS. FIG. 5A is a plan view showing the back surface (side surface opposite to the light incident surface) of the solar cell module 20. As shown in FIG. 5A, the back surface side of the solar cell module 20 is covered with the back surface protection material 11. Moreover, the terminal box 12 is provided along each of 2 sides which oppose among the 4 sides of the solar cell module 20. The terminal box 12 is provided on the side corresponding to the side on which the bus bar 3 described later is provided. Two connection cables 21 are drawn out from each terminal box 12 by two.

  FIG. 5B is a plan view showing the back surface with the terminal box 12 removed. That is, it is a plan view of the back surface protective material 11. The back surface protective material 11 is provided with an opening 22 at a position corresponding to the terminal box 12. This opening 22 is for passing wiring for taking out electric power from the inside of the solar cell module to the outside.

  A single-layer sheet material is used as the back surface protection material 11. As a material of the back surface protective material 11, a material that can be laminated, has no water permeability, is made of a nonmetal, and is insulative is used. An example of such a material is a resin sheet material containing EPDM (ethylene / propylene rubber) as a main component. An example of such a resin sheet material containing EPDM as a main component is BRPC (trade name, manufactured by BRP).

  Then, with reference to FIG.5 (c) and FIG. 6, the structure of the part coat | covered with the back surface protection material 11 is demonstrated. FIG.5 (c) is a top view which shows the state which removed the back surface protection material 11 from the state of FIG.5 (b) further. FIG. 6 is a cross-sectional view taken along the line AA in FIG.

  As shown in FIG. 5C, the solar cell module 20 has a structure in which a solar cell film 40 is formed on the substrate 1. The solar cell film 40 has a structure in which the transparent conductive layer 2, the photoelectric conversion layer 5, and the back electrode layer 6 are laminated from the substrate 1 side. Each layer will be described later. The solar cell film 40 is provided on the central portion side of the substrate 1, and the outer peripheral side is a peripheral portion 8 where the substrate 1 is exposed. The solar cell film 40 is divided into a plurality of strip-shaped power generation cells 9 by the cell dividing grooves 4. The plurality of power generation cells 9 are arranged parallel to each other with their long sides adjacent to each other. Although not shown in FIG. 5C, the cell dividing groove 4 divides the groove 4-1 that divides the transparent conductive layer, the groove 4-2 that divides the photoelectric conversion layer, the back electrode layer, and the photoelectric conversion layer. It is formed by the groove 4-3. By embedding the groove 4-2 in the back electrode layer, the plurality of power generation cells 9 are electrically connected in series. The solar cell film 40 is provided with two insulating grooves 7. Each insulating groove 7 is provided in the vicinity of the short side of the power generation cell 9 in parallel with the short side. The insulating groove 7 is a portion where the solar cell film 40 is removed and the substrate 1 is exposed, like the peripheral portion 8. The insulating groove 7 is provided to prevent a short circuit between the power generation cell 9 and the outside.

  Of the plurality of power generation cells 9, the power generation cells 9 at both ends (hereinafter sometimes referred to as current collection cells) are provided with bus bars 3, respectively. The bus bar 3 is provided so as to overlap almost the entire current collecting cell. The bus bar 3 is electrically connected to the electrode of each current collection cell. The bus bar 3 is provided so that the power collected in the current collection cell can be collected without loss up to the position where it is taken out. The bus bar 3 is provided so as to be mostly covered with the solar cell film 9. However, in the take-out part 10, the solar cell film 9 on the bus bar 3 is removed, and the bus bar 3 is exposed. This take-out portion 10 corresponds to a position where the terminal box 12 is disposed. In the take-out part 10, the wiring in the terminal box 12 is electrically connected by soldering or the like. Thereby, the electric power generated by the power generation of the solar cell film 9 is taken out to the outside.

  The configuration of the bus bar 3 will be described with reference to FIG. FIG. 6 is a cross-sectional view taken along the line AA in FIG. As shown in FIG. 6, the solar cell module 20 includes a substrate 1, a solar cell film 40, and a bus bar 3. The solar cell film 40 has a transparent conductive layer 2, a photoelectric conversion layer 5, and a back electrode layer 6. The transparent conductive layer 2 is formed on the substrate 1. In the extraction unit 10, the bus bar 3 is provided on a part of the transparent conductive layer 2, and the photoelectric conversion layer 5 is provided on the other part of the transparent conductive layer 2. A back electrode layer 6 is further formed on the photoelectric conversion layer 5. On the other hand, the photoelectric conversion layer 5 and the back electrode layer 6 are not provided on the bus bar 3, and the bus bar 3 is exposed. The exposed part of the bus bar 3 is the take-out part 10. As shown in FIG. 5C, the upper portion of the bus bar 3 is covered with a solar cell film 40 in portions other than the take-out portion 10. That is, it is covered with the photoelectric conversion layer 5 and the back electrode layer 6.

  Then, the manufacturing method of the solar cell panel which concerns on this embodiment is demonstrated. FIG. 7 is a flowchart of the method for manufacturing the solar cell panel. The solar cell panel 30 is manufactured by steps S10 to S150 shown in FIG. The operation of each process will be described in detail below. Here, an example in which a single layer amorphous silicon thin film solar cell is used as the solar cell power generation cell 5 on a glass substrate as the substrate 1 will be described.

Step S10: Formation of Transparent Conductive Layer As shown in FIG. 8A (a), a soda float glass substrate (1.4 m × 1.1 m × plate thickness: 4 mm) is prepared as the substrate 1. It is desirable that the end face of the substrate is corner chamfered or rounded to prevent breakage. Subsequently, as shown in FIG. 8A (b), a transparent electrode film mainly composed of a tin oxide film (SnO ₂ ) is formed as a transparent conductive layer 2 at about 500 to 800 nm at about 500 ° C. using a thermal CVD apparatus. Membrane treatment. At this time, a texture with appropriate irregularities is formed on the surface of the transparent electrode film. As the transparent conductive layer 2, in addition to the transparent electrode film, an alkali barrier film (not shown) may be formed between the substrate 1 and the transparent electrode film. As the alkali barrier film, a silicon oxide film (SiO ₂ ) is formed at a temperature of about 500 ° C. in a thermal CVD apparatus with a thickness of 50 to 150 nm.

Step S20: Formation of Firing Electrode As shown in FIG. 8A (c), the bus bar 3 is formed. An electrode paste for forming a fired electrode is applied along a position to be a current collecting cell. The electrode paste is a mixture of Ag and SiO ₂ in a solvent. The substrate to be processed with the electrode paste applied is baked. Thereby, the fired electrode as the bus bar 3 is formed on the transparent conductive layer 2.

  Here, it is preferable that the temperature at the time of baking a to-be-processed substrate is 300 to 500 degreeC. When baking is performed at a temperature higher than 500 ° C., the tin oxide film of the transparent conductive layer 2 as a base may be corroded and peeled off. When fired at a temperature lower than 300 ° C., the solvent of the paste becomes difficult to volatilize, and it may take time for firing or the solvent may remain in the electrode.

Step S30: Laser Etching As shown in FIG. 8A (d), the transparent conductive layer 2 is divided by laser etching so as to correspond to the power generation cells 9. Specifically, the substrate 1 is placed on an XY table, and the first harmonic (1064 nm) of a laser diode-pumped YAG laser is incident from the film surface side of the transparent electrode film. Pulse oscillation: 5 to 20 kHz, the laser power is adjusted so as to be suitable for the processing speed, and the transparent electrode film is formed in the direction perpendicular to the series connection direction of the power generation cells 9 so as to form the groove 4-1. Laser etching into strips with a width of about 6-10 mm.

Step S40; Film Formation of Photoelectric Conversion Layer As shown in FIG. 8A (e), the photoelectric conversion layer 5 is formed on the transparent conductive layer 2 and the bus bar 3. Specifically, a p-layer film / i-layer film / n-layer film made of an amorphous silicon thin film as the photoelectric conversion layer 5 is sequentially formed by a plasma CVD apparatus at a reduced pressure atmosphere: 30 to 150 Pa and about 200 ° C. The photoelectric conversion layer 5 is formed on the transparent conductive layer 2 using SiH ₄ gas and H ₂ gas as main raw materials. The p-layer, i-layer, and n-layer are stacked in this order from the sunlight incident side. In this embodiment, the photoelectric conversion layer 5 is a p-layer: B-doped amorphous SiC and a thickness of 10 to 30 nm, an i-layer: amorphous Si and a thickness of 250 to 350 nm, and an n-layer: p-doped microcrystalline Si. The film thickness is 30 to 50 nm. A buffer layer may be provided between the p layer film and the i layer film in order to improve the interface characteristics.

Step S50; Laser Etching As shown in FIG. 8A (f), the photoelectric conversion layer 5 is divided by laser etching so as to correspond to the power generation cells 9. Specifically, the substrate 1 is placed on an XY table, and the second harmonic (532 nm) of a laser diode-pumped YAG laser is incident from the film surface side of the photoelectric conversion layer 5. Pulse oscillation: 10 to 20 kHz, the laser power is adjusted so as to be suitable for the processing speed, and a lateral side of about 100 to 150 μm of the laser etching line (groove 4-1) of the transparent conductive layer 2 is formed on the groove 4-2. Laser etching to form

Step S60: Formation of Back Electrode Layer As shown in FIG. 8B (g), an Ag film / Ti film is sequentially formed as a back electrode layer 6 at about 150 ° C. in a reduced pressure atmosphere by a sputtering apparatus. In this embodiment, the back electrode layer 6 is formed by stacking an Ag film: 200 to 500 nm and a Ti film having a high anticorrosive effect: 10 to 20 nm in this order as a protective film. For the purpose of reducing contact resistance between the n-layer and the back electrode layer 6 and improving light reflection, a GZO (Ga-doped ZnO film) film thickness between the photoelectric conversion layer 5 and the back electrode layer 6 is 50 to 100 nm, a sputtering apparatus. May be provided by forming a film.

Step S70; Laser Etching Further, the photoelectric conversion layer 5 and the back electrode layer 6 are divided in accordance with the power generation cell 9 by laser etching. Specifically, the target substrate 1 is placed on an XY table, and the second harmonic (532 nm) of a laser diode-pumped YAG laser is incident from the substrate 1 side, so that the laser light is converted into the photoelectric conversion layer 5. The back electrode layer 6 is exploded and removed by the high gas vapor pressure generated at this time. Pulse oscillation: 1 to 10 kHz, the laser power is adjusted so as to be suitable for the processing speed, and the lateral side of about 250 μm to 400 μm of the laser etching line (groove 4-1) of the transparent conductive layer 2 is formed in the groove 4-3. Laser etching to form

Step S80: Formation of Insulating Groove As shown in FIG. 8B (h), the insulating groove 7 is formed. Specifically, the power generation region is divided to remove the influence that the serial connection portion due to laser etching is likely to be short-circuited at the film edge around the substrate edge. The substrate to be processed is placed on an XY table, and the second harmonic (532 nm) of the laser diode-pumped YAG laser is incident from the substrate 1 side, so that the laser light is transmitted between the transparent conductive layer 2 and the photoelectric conversion layer 3. The back electrode layer 6 is exploded and removed using the high gas vapor pressure that is absorbed and generated at this time. Pulse oscillation: 1 to 10 kHz The laser power is adjusted so as to be suitable for the processing speed, and the insulating groove 7 is positioned at a position of 5 to 15 mm from the end of the substrate to be processed in parallel with the short side direction of the power generation cell 9. Laser etching to form At this time, no insulating groove is provided in the long side direction.

  The insulating groove 7 finishes the etching at a position of 5 to 10 mm from the end of the substrate to be processed. The etching may be terminated by stopping the laser beam, but can be dealt with simply by installing a metallic masking plate in the non-laser etching region. By terminating the etching at a position of 5 to 10 mm from the edge of the substrate 1, an effective effect is exhibited in suppressing external moisture intrusion into the solar cell module from the end of the solar cell panel.

Step S90: Expose the sintered electrode / removal of the peripheral film As shown in FIG. 8B (i), the solar cell film in the peripheral portion 8 and the extraction portion 10 is removed by the polishing process. The removal of the peripheral edge portion 8 is performed in order to ensure a healthy bonding surface with the back surface protective material 11 in a later step. In the peripheral portion 8, the solar cell film (back electrode layer 6 / photoelectric conversion layer 5 / transparent conductive layer 2) on the substrate end side with respect to the insulating groove 7 is polished and removed by 5 to 15 mm from the end of the substrate to be processed. On the other hand, in the extraction part 10, only the back electrode layer 6 and the photoelectric conversion layer 5 are removed, and the bus bar 3 is exposed. Thus, in order to selectively remove a part of the solar cell film 40, for example, a masking material is disposed on a part where the solar cell film 40 is not removed, and blast polishing is performed. Note that the polishing scraps and abrasive grains were removed by washing the substrate 1.

  The removal of the peripheral portion 8 and the removal of the take-out portion 10 may be performed in the same process or in separate processes. Further, when the back electrode layer 6 and the photoelectric conversion layer 5 are removed by the extraction portion 10, laser etching may be used.

Step S100: Attaching the back surface protection sheet As shown in FIG. 8B (j), the back surface protection material 11 is disposed and laminated. The back surface protective material 11 is provided with an opening 22 at a position corresponding to the take-out portion 10. In other words, the bus bar 3 is still exposed at the opening 22.

Step S110: Attachment of Terminal Box As shown in FIG. 8B (k), the terminal box 12 is attached at a position corresponding to the opening 22 using an adhesive. That is, the terminal box 12 is attached to two places.

Step S120: Wiring in the terminal box Further, the terminal box 12 is wired. Specifically, the wiring is performed so that the bus bar 3 and the connection cable 21 are electrically connected in the terminal box 12. Connection to the bus bar 3 is performed by solder or the like.

Step S130: Injection of potting material Further, a sealing material (potting material) is injected into the terminal box 12 and sealed. Thereby, the solar cell module 20 is completed.

Step S140: Place Solar Cell Module on Base Subsequently, the completed solar cell module 20 is placed on the base 14 as shown in FIG.

Step S150: Fixing Further, the solar cell module 20 is fixed to the base 14 by using the fixing bracket 17 and the screw 18. Thereby, the solar cell panel 30 shown in FIG. 3 is completed.

  The effect of the solar cell panel concerning this embodiment demonstrated above is demonstrated. When a copper foil is used as a bus bar as in the conventional example shown in FIG. 2 (a), there is a concern that misalignment or the like may occur when the copper foil is disposed on the solar cell film. On the other hand, in the present embodiment, since the fired electrode is used as the bus bar, there is no concern about such misalignment.

  Moreover, in this embodiment, the wiring from a bus bar to a terminal box can be simplified by providing two terminal boxes on the bus bars at both ends. That is, as in the conventional example shown in FIG. 2A, in order to electrically connect the bus bar and the wiring inside the terminal box, it is not necessary to arrange the extraction wiring so as to straddle the solar cell film. . Therefore, the configuration is further simplified.

  Further, in this embodiment, since a single-layer sheet material is used as the back surface protective material, there is no need for a back sheet in which a plurality of layers are laminated as in the conventional example, or an adhesive, and the configuration is further simplified. Yes.

  Furthermore, since this back surface protective material is a non-metallic sheet material, the increase in the electrostatic capacity of the solar cell panel can be suppressed. By suppressing the increase in capacitance in this way, erroneous detection of the ground fault current detection device can be prevented.

  Moreover, in this embodiment, since a solar cell module is fixed by a fixing member at a plurality of fixing points, a frame is not necessary. When the solar cell module is fixed by a metal frame (frame) as in the conventional example shown in FIG. 1, moisture may enter the gap between the solar cell module and the frame. In such a case, a ground fault current may flow from the solar cell module through moisture and a metal frame. On the other hand, in this embodiment, since no frame is used, the possibility of water accumulation is low, and the occurrence of a ground fault current via water is suppressed.

  In this embodiment, the case where a single amorphous silicon layer is used as the photoelectric conversion layer has been described. However, the photoelectric conversion layer is replaced with a tandem type in which an amorphous silicon layer and a microcrystalline silicon layer are stacked. However, it is obvious to those skilled in the art that the effects of the present invention can be achieved.

It is the (a) top view of the conventional solar cell panel, and (b) sectional drawing. It is the (a) top view which shows the wiring structure of a conventional solar cell panel, and a solar cell film | membrane structure, and (b) sectional drawing. It is a perspective view of the solar cell panel concerning the present invention. It is a perspective view which shows the structure of a base. It is a top view of a base. It is a perspective view which shows the example of a rib structure. It is a top view which shows the back surface side of a solar cell panel. It is sectional drawing along the AA line of FIG.5 (c). It is a flowchart of the solar cell panel manufacturing method. It is a top view which shows the structure in the manufacturing process of a solar cell panel. It is a top view which shows the structure in the manufacturing process of a solar cell panel. It is a perspective view which shows a mode that a solar cell module is mounted in a base.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Transparent conductive layer 3 Bus bar 4 Cell separation groove 5 Photoelectric conversion layer 6 Back surface electrode layer 7 Insulation groove 8 Peripheral part 9 Power generation cell 10 Extraction part 11 Back surface protection material 12 Terminal box 13 Rib structure 14 Base 15 Helisert 16 Notch 17 Fixing bracket 18 Screw 20 Solar cell module 21 Connection cable 22 Opening 30 Solar cell panel 40 Solar cell membrane

Claims (33)

A substrate,
A solar cell film provided on the substrate;
A bus bar,
Comprising
The solar cell membrane is divided into a plurality of strip-shaped power generation cells,
The plurality of power generation cells are electrically connected in series,
The bus bar is electrically provided for each of the power generation cells at both ends,
The bus bar is a solar cell module that is a fired electrode obtained by firing a paste-like raw material containing a conductive material. The solar cell module according to claim 1, wherein
Furthermore,
It has a take-out portion provided corresponding to each of the bus bars,
The take-out part is provided on the bus bar,
The solar cell module wired so that electric power may be taken out from the bus bar through the take-out portion. The solar cell module according to claim 1 or 2, wherein
The fired electrode includes Ag and SiO ₂ ,
A solar cell module in which a main component of the fired electrode is Ag. The solar cell module according to any one of claims 1 to 3, wherein
The solar cell film is
A transparent conductive layer;
A photoelectric conversion layer;
A back electrode layer;
Including
The bus bar is a solar cell module provided on the transparent conductive layer. The solar cell module according to any one of claims 1 to 4, wherein
The thickness of the said bus bar is a solar cell module which is 15 micrometers-50 micrometers. A solar cell module according to any one of claims 1 to 5,
Furthermore,
Comprising a back surface protective material covering the solar cell film;
The back surface protection material is a solar cell module that is a single sheet material. The solar cell module according to claim 6, wherein
The back surface protection material is a solar cell module that is a non-metallic sheet material. The solar cell module according to claim 7, wherein
The said back surface protection material is a solar cell module which is a sheet | seat material which has ethylene propylene rubber as a main component. A solar cell module according to any one of claims 1 to 8,
A base on which the solar cell module is placed;
A plurality of fixing members for fixing the solar cell module to the base;
Comprising
The solar cell module is a solar cell panel fixed by the plurality of fixing members at a plurality of fixing points. A solar cell panel according to claim 9, wherein
The base is a solar cell panel having a rib structure. It is a solar cell panel according to claim 9 or 10,
The base is a solar cell panel having a through structure. A solar cell panel according to any one of claims 9 to 11,
The base is a solar panel made of plastic. A solar cell panel according to claim 12, comprising:
The base is a solar cell panel including high density polyethylene. A solar cell panel according to any one of claims 9 to 11,
The base is a solar cell panel made of metal. The solar cell panel according to claim 14, wherein
The base is a solar panel including aluminum. A solar cell film forming step for forming a solar cell film divided into a plurality of strip-shaped power generation cells on the substrate,
A bus bar forming step of connecting a bus bar to a part of the solar cell film;
A terminal box mounting step for forming a terminal box for storing wiring for extracting electric power from the bus bar to the outside;
Comprising
The plurality of power generation cells are electrically connected in series,
In the bus bar forming step, the bus bar is formed so as to be electrically connected to each of the power generation cells at both ends,
The bus bar forming step includes
A process of applying a paste-like raw material containing a conductive substance;
A firing step of firing the applied raw material into a fired electrode;
Have
In the terminal box mounting step, the terminal box is attached to each end of the power generation cell in the series connection direction on the substrate, respectively. It is a manufacturing method of the solar cell module according to claim 16,
The fired electrode includes Ag and SiO ₂ ,
The manufacturing method of the solar cell module whose main component of the said baking electrode is Ag. A method for manufacturing a solar cell module according to claim 16 or 17,
The solar cell film forming step,
A transparent conductive layer forming step of forming a transparent conductive layer on the substrate;
A photoelectric conversion layer forming step of forming a photoelectric conversion layer on the substrate on which the transparent conductive layer is formed;
A back electrode layer forming step of forming a back electrode layer on the substrate on which the photoelectric conversion layer is formed;
Including
The said bus-bar formation process is a manufacturing method of the solar cell module implemented between the said transparent conductive layer formation process and the said photoelectric converting layer formation process. A method for manufacturing a solar cell module according to claim 18,
The manufacturing method of the solar cell module baked at the temperature of 300 to 500 degreeC in the said baking process. A method for manufacturing a solar cell module according to claim 18 or 19,
Furthermore,
A method for manufacturing a solar cell module, comprising a bus bar exposing step, which is performed after the back electrode layer forming step and which exposes at least a part of the bus bar by removing the back electrode layer and the photoelectric conversion layer. A method for manufacturing a solar cell module according to any one of claims 16 to 20, comprising:
The thickness of the said bus bar is a manufacturing method of the solar cell module which is 15 micrometers-50 micrometers. A method of manufacturing a solar cell module according to any one of claims 16 to 21,
Furthermore,
Comprising a back surface protective material forming step of covering the solar cell film with a back surface protective material;
The said back surface protection material is a manufacturing method of the solar cell module which is a single sheet material. It is a manufacturing method of the solar cell module according to claim 22,
The said back surface protection material is a manufacturing method of the solar cell module which is a sheet material which has ethylene propylene rubber as a main component. A step of placing a solar cell module manufactured by the method for manufacturing a solar cell module according to any one of claims 16 to 23 on a base;
A fixing step of fixing the mounted solar cell module to the base by a plurality of fixing members;
Comprising
The said fixing process WHEREIN: The said solar cell module is a manufacturing method of the solar cell panel fixed by the said some fixing member at several fixing points. A method of manufacturing a solar cell panel according to claim 24,
The method for manufacturing a solar cell panel, wherein the base is made of plastic. A method of manufacturing a solar cell panel according to claim 25,
The said base is a manufacturing method of the solar cell panel containing the high density polyethylene. A method of manufacturing a solar cell panel according to claim 24,
The said base is a manufacturing method of the solar cell panel which is metal. It is a manufacturing method of the solar cell panel according to claim 27,
The base is a method for manufacturing a solar cell panel including aluminum. A solar cell module;
A base on which the solar cell module is placed;
A plurality of fixing members for fixing the solar cell module to the base;
Comprising
The solar cell module is a solar cell panel fixed by the plurality of fixing members at a plurality of fixing points. A solar cell panel according to claim 29, wherein
The base is a solar panel made of plastic. A solar cell panel according to claim 30, wherein
The base is a solar cell panel including high density polyethylene. A solar cell panel according to claim 29, wherein
The base is a solar cell panel made of metal. A solar cell panel according to claim 32, wherein
The base is a solar panel including aluminum.

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