JP2013197182A - Method for manufacturing solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently manufacture a solar cell module by performing a step of measuring output characteristics of solar cells in conjunction with a step of modularizing the solar cells.SOLUTION: A method for manufacturing a solar cell module comprises the steps of: arranging a tab line 20 on solar cells 1 and 30 via an adhesive 21; connecting the tab line 20 to measuring instruments A and V which measure output characteristics of the solar cells 1 and 30 and measuring the output characteristics of the solar cells 1 and 30; determining grades of the solar cells 1 and 30 according to the measurement results of the measurement instruments A and V; and modularizing the solar cells 1 and 30 per grade.

Description

  The present invention relates to a method for manufacturing a solar cell module, and more particularly to a method for manufacturing a solar cell module in which a grade of a solar cell is determined in a manufacturing process and a string is formed according to the grade.

  Conventionally, as a measurement jig for measuring the electrical characteristics of a solar cell, a measurement jig having a plurality of probe pins that are in contact with bus bar electrodes of the solar cell is generally used. This type of measuring jig has a current measuring probe pin for measuring a current flowing through the solar cell and a voltage measuring probe pin for measuring a voltage generated in the solar cell.

  For example, as shown in FIGS. 9 and 10, the measurement of the electrical characteristics of the solar cell is performed by placing the current measurement probe pin 50 and the voltage measurement probe pin 51 on the bus bar electrode 54 of the solar cell 53 to be measured. This is performed by a so-called four-terminal method in which the current flowing through the solar cell 53 and the voltage generated in the solar cell 53 are measured while irradiating the light receiving surface of the solar cell 53 with pseudo sunlight.

  Here, in order to reduce the number of manufacturing steps of solar cells and reduce the amount of electrode materials such as Ag paste and reduce the manufacturing cost in recent years, a conductive adhesive film is provided without providing bus bar electrodes. There has been proposed a method of directly connecting a tab wire serving as an interconnector so as to cross the finger electrode. Even in such a solar cell having a bus bar-less structure, the current collection efficiency is equal to or higher than that of a solar cell having a bus bar electrode.

  When measuring the electrical characteristics of the solar cell 55 having such a bus barless structure, the probe pin 56 needs to be in direct contact with the finger electrode 57. However, as shown in FIG. 11, the interval between the probe pins 56 and the interval at which the finger electrodes 57 are formed often do not coincide with each other. In this case, conduction to all the finger electrodes 57 can be achieved. Therefore, finger electrodes 57 that are not measured are generated, and accurate electrical characteristics cannot be measured.

  In order to solve these problems, we propose a measurement method that uses a rectangular plate-shaped bar electrode as a measurement terminal and arranges it on the light-receiving surface of the solar cell so as to cross all finger electrodes, instead of using probe pins. Has been.

JP 2006-118983 A JP 2010-177379 A

  The solar cells on which the output characteristics are measured are graded according to the output characteristics. For example, the grade classification is performed on a solar cell for a high-quality solar cell module with good output characteristics and a solar cell for an ordinary solar cell module whose output characteristics satisfy a predetermined standard but are not good.

  Thereafter, the solar cells are arranged for each grade, and a string is formed by connecting the solar cells to each other by tab wires. Here, if the measurement of the output characteristics of the solar cell and the formation of the solar cell string are smoothly linked, it is desirable that the manufacturing process of the solar cell module becomes efficient.

  Therefore, the present invention can efficiently manufacture a solar cell module by linking the steps of measuring the output characteristics of the solar cell and modularizing the solar cell. It aims at providing the manufacturing method of a solar cell module.

  In order to solve the above-described problems, a method for manufacturing a solar cell module according to the present invention includes a step of arranging a tab wire on an electrode of a solar cell via an adhesive, and the output of the tab wire and the solar cell. Connecting a measuring device for measuring characteristics, measuring the output characteristics of the solar cell, determining the solar cell grade according to the measurement result of the measuring device, and the solar cell for each grade And modularizing.

  According to the present invention, by using a tab line as a power characteristic measurement terminal, it is possible to continuously perform power characteristic measurement, grade classification, and modularization. Therefore, according to such a method for manufacturing a solar cell module, the manufacturing process can be made efficient without using a dedicated jig for measuring the output characteristics of the solar cell.

It is a figure which shows the manufacturing process of the thin film solar cell module to which this invention was applied, (a) is a perspective view which sticks a laminated body, (b) is a top view. It is a perspective view of a thin film solar cell module to which the present invention is applied. It is sectional drawing which shows the laminated body of a tab wire and an adhesive bond layer. It is a top view of a thin film solar cell module. It is process drawing which shows the manufacturing process of the solar cell module to which this invention was applied. 1 is a perspective view of a silicon-based solar cell module to which the present invention is applied. It is a figure which shows the measurement process of the output characteristic of a silicon-type solar cell, (a) is a perspective view, (b) is sectional drawing. It is sectional drawing which shows the string of a silicon type photovoltaic cell. It is a perspective view which shows the state which measures the electrical property of a solar cell using the measuring device using the conventional probe pin. It is a figure for demonstrating the measurement by the measuring apparatus using the conventional probe pin. It is a figure for demonstrating the measurement of the electrical property of the solar cell of a bus-bar-less structure with the measuring apparatus using the conventional probe pin.

  Hereinafter, a method for manufacturing a solar cell module to which the present invention is applied will be described in detail with reference to the drawings. It should be noted that the present invention is not limited to the following embodiments, and various modifications can be made without departing from the scope of the present invention. Further, the drawings are schematic, and the ratio of each dimension may be different from the actual one. Specific dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

[Thin film solar cell module]
As a solar cell constituting the solar cell module, a so-called thin film solar cell 1 in which a semiconductor layer that is a photoelectric conversion layer is formed on a substrate such as glass or stainless steel can be used. As shown in FIGS. 1A and 1B, the thin-film solar cell 1 constitutes a solar cell string in which a plurality of solar cells 2 are connected by contact lines. As shown in FIG. 2, the thin-film solar cell 1 having this string structure is a single unit or a plurality of connected matrixes, and a sheet 3 and a back sheet 4 of a sealing adhesive are provided on the back side. The solar cell module 6 is formed by laminating together. In addition, the solar cell module 6 is appropriately attached with a metal frame 7 such as aluminum around it.

  As the sealing adhesive, for example, a translucent sealing material such as ethylene vinyl acetate resin (EVA) is used. Further, as the back sheet 4, a plastic film or sheet excellent in various properties such as weather resistance, heat resistance, water resistance, and light resistance is used. For example, polyvinyl fluoride that takes advantage of the high resistance of a fluorine-based resin. A laminated sheet having a configuration of (PVF) / polyethylene terephthalate (PET) / polyvinyl fluoride (PVF) can be used.

[Solar cells]
In the thin film solar cell 1 to which the present invention is applied, a transparent electrode film made of a transparent conductive film, a photoelectric conversion layer, and a back electrode film are laminated in this order on a translucent insulating substrate 8 although not shown. This is a super-straight type solar cell in which light is incident from the translucent insulating substrate 8 side. In addition, there exists a substrate type solar cell formed in order of the base material, the back surface electrode, the photoelectric converting layer, and the transparent electrode in the thin film solar cell. Hereinafter, the super straight type thin film solar cell 1 will be described as an example, but the present technology can also be used for a substrate type thin film solar cell.

  The solar cell to which the present invention is applied is generally a thin film solar cell, for example, various thin film solar cells such as amorphous silicon, microcrystalline tandem, CdTe, CIS, flexible, or so-called single crystal silicon solar cells, polycrystalline So-called silicon solar cells such as silicon solar cells and HIT solar cells can be used.

  As the translucent insulating substrate 8, a heat resistant resin such as glass or polyimide can be used.

The transparent electrode film may be, for example, _{SnO 2, ZnO, ITO, IZO} , AZO ( transparent electrode material was doped with Al in the zinc oxide) and the like. As the photoelectric conversion layer, a silicon-based photoelectric conversion film such as amorphous silicon, microcrystalline silicon, or polycrystalline silicon, or a compound-based photoelectric conversion film such as CdTe, CuInSe ₂ , or Cu (In, Ga) Se ₂ can be used. .

For example, the back electrode film has a laminated structure of a transparent conductive film and a metal film. For the transparent electrode film, SnO ₂ , ZnO, ITO, IZO, AZO, or the like can be used. Silver, aluminum, or the like can be used for the metal film.

  As shown in FIG. 1A, the thin-film solar cell 1 configured in this manner has a plurality of rectangular solar cells 2 having a length that extends over almost the entire width of the translucent insulating substrate 8. Each solar battery cell 2 is separated by an electrode dividing line, and one transparent electrode film and the other back electrode film are connected to each other in the adjacent solar battery cells 2 and 2 by a contact line. A solar battery string in which the solar battery cells 2 are connected in series is configured.

  The thin-film solar cell 1 is formed with a linear P-type electrode terminal portion 9 having substantially the same length as the solar cell 2 on the end of the transparent electrode film of the solar cell 2 at one end of the solar cell string. A linear N-type electrode terminal portion 10 having substantially the same length as that of the solar battery cell 2 is formed on the end of the back electrode film of the solar battery cell 2 at the other end. In the thin-film solar cell 1, the P-type electrode terminal portion 9 and the N-type electrode terminal portion 10 serve as an electrode extraction portion, and supplies electricity to the terminal box 19 via the positive electrode tab wire 11 and the negative electrode tab wire 15.

  The positive electrode tab wire 11 and the negative electrode tab wire 15 are connected to the P-type electrode terminal portion 9 and the N-type electrode terminal portion 10 of the thin-film solar cell 1 to take out electrodes, and at the time of measuring power characteristics, It becomes a measurement terminal connected to the meter A and the voltmeter V. As shown in FIG. 3, the positive electrode tab wire 11 and the negative electrode tab wire 15 are configured, for example, by laminating and integrating an adhesive layer 21 on one surface of the tab wire 20.

  As shown in FIG. 4, the positive electrode tab wire 11 includes a positive electrode current collecting tab portion 12 connected to the P-type electrode terminal portion 9 of the thin-film solar cell 1 through an adhesive layer 21, an ammeter A and a voltage. The positive electrode connection tab portion 13 is connected to the total V and connected to the terminal box 19, and the positive electrode current collection tab portion 12 and the positive electrode connection tab portion 13 are continuous via the folded portion 14. In FIG. 4, for convenience, the sheet 3 and the back sheet 4 of the sealing adhesive are omitted.

  The positive electrode connection tab portion 13 is connected to the ammeter A and the voltmeter V when measuring the power characteristics of the thin film solar cell 1. When the thin film solar cell 1 is modularized, the sheet 3 and the back sheet 4 of the sealing adhesive are used. Is connected to a terminal box 19 provided on the back sheet 4.

  The negative electrode tab wire 15 is connected to the negative electrode current collecting tab portion 16 connected to the N-type electrode terminal portion 10 of the thin-film solar cell 1 through the adhesive layer 21, the ammeter A, and the voltmeter V. A negative electrode connection tab portion 17 connected to the terminal box 19 is provided, and the negative electrode current collection tab portion 16 and the negative electrode connection tab portion 17 are continuous via a folded portion 18.

  The negative electrode connection tab portion 17 is connected to the ammeter A and the voltmeter V when measuring the power characteristics of the thin film solar cell 1. When the thin film solar cell 1 is modularized, the sheet 3 and the back sheet 4 of the sealing adhesive are used. Is connected to a terminal box 19 provided on the back sheet 4.

  In the following, the positive electrode tab wire 11 will be described in detail, but the negative electrode tab wire 15 also has the same configuration as the positive electrode tab wire 11.

  The tab wire 20 is formed by, for example, slitting a copper foil or aluminum foil rolled to a thickness of 9 to 300 μm, or by rolling a thin metal wire such as copper or aluminum into a flat plate shape. 9 is a rectangular wire having a width of approximately 1 to 3 mm, which is approximately the same width as 9.

  The positive electrode current collecting tab portion 12 has substantially the same length as the P-type electrode terminal portion 9 and is formed on the entire surface of the P-type electrode terminal portion 9 via an adhesive layer 21 laminated on one surface of the tab wire 20. It is joined electrically and mechanically. Further, the positive electrode connection tab portion 13 is a portion where a part of the positive electrode tab wire 11 is folded back by the folded portion 14, and is connected to the ammeter A or the voltmeter V when measuring the power characteristics of the thin film solar cell 1. In the subsequent modularization, the sealing adhesive sheet 3 and the back sheet 4 are inserted through the insertion holes and folded back onto the back sheet 4 so that the tip is on the back sheet 4. It is connected to the terminal block of the provided terminal box 19.

  The folded portion 14 is provided at a part of the positive electrode tab wire 11, for example, at the end of the positive electrode current collecting tab portion 12. The positive electrode tab wire 11 becomes the positive electrode connection tab portion 13 before the folded portion 14. Accordingly, in the positive electrode tab wire 11, the positive electrode current collecting tab portion 12 and the positive electrode connection tab portion 13 are continuous through the folded portion 14, and do not have a junction portion. It is possible to prevent an increase in the thickness, a decrease in connection reliability of the joint portion, damage to the translucent insulating substrate 8 due to heat and stress concentrating on the joint portion, and the like.

  The positive electrode tab wire 11 has a length that is approximately twice the length of the P-type electrode terminal portion 9 and is preferably folded back at a position that is approximately 50% of the total length. Thereby, the positive electrode tab wire 11 can reliably connect the positive electrode connection tab portion 13 to the terminal box 19 regardless of the position of the terminal box 19 on the back sheet 4 of the thin film solar cell 1. The same applies to the negative electrode tab wire 15.

  As shown in FIG. 3, the positive electrode tab wire 11 and the negative electrode tab wire 15 are provided with an adhesive layer 21 connected to the P-type electrode terminal portion 9 or the N-type electrode terminal portion 10 on one surface 20 a of the tab wire 20. ing. The adhesive layer 21 is provided on the entire surface 20 a of the tab wire 20, and is composed of, for example, coating solder or a conductive adhesive film 23.

  As shown in FIG. 3, the conductive adhesive film 23 includes a thermosetting binder resin layer 24 containing conductive particles 25 at a high density. Moreover, as for the electroconductive adhesive film 23, it is preferable that the minimum melt viscosity of binder resin is 100-100000 Pa.s from a pressable viewpoint. If the minimum melt viscosity of the conductive adhesive film 23 is too low, the resin flows in the process of low pressure bonding to main curing, and connection failure or protrusion to the cell surface is likely to occur. Moreover, even if the minimum melt viscosity is too high, defects are likely to occur when the film is adhered, and the connection reliability may be adversely affected. The minimum melt viscosity can be measured while a sample is loaded in a predetermined amount of rotational viscometer and raised at a predetermined temperature increase rate.

  The conductive particles 25 used for the conductive adhesive film 23 are not particularly limited. For example, metal particles such as nickel, gold, silver, and copper, those obtained by applying gold plating to resin particles, and gold plating on resin particles. And the like.

  The conductive particles may be a powder in which one particle or one particle exists individually, but it is preferable that the conductive particles have a chain shape in which primary particles are continuous. An example of the former is a spherical nickel powder having spike-like protrusions, and an example of the latter that is preferably used is a filamentous nickel powder. By using the latter, the conductive particles 25 have elasticity, the connection reliability between the positive electrode tab wire 11 and the P-type electrode terminal portion 9 having different physical properties, and the negative electrode tab wire 15 and the N-type electrode terminal portion 10. The connection reliability of each can be improved.

  In addition, it is preferable that the electroconductive adhesive film 23 is 10-10000 kPa * s at the normal temperature vicinity, More preferably, it is 10-5000 kPa * s. When the viscosity of the conductive adhesive film 23 is in the range of 10 to 10000 kPa · s, when the conductive adhesive film 23 is provided on the one surface 20a of the tab wire 20 and wound around the reel 26, blocking due to so-called protrusion is prevented. And a predetermined tack force can be maintained.

  The composition of the binder resin layer 24 of the conductive adhesive film 23 is not particularly limited as long as it does not impair the above-described characteristics, but more preferably a film-forming resin, a liquid epoxy resin, a latent curing agent, and a silane Containing a coupling agent.

  The film-forming resin corresponds to a high molecular weight resin having an average molecular weight of 10,000 or more, and preferably has an average molecular weight of about 10,000 to 80,000 from the viewpoint of film formation. As the film-forming resin, various resins such as an epoxy resin, a modified epoxy resin, a urethane resin, and a phenoxy resin can be used. Among them, a phenoxy resin is preferably used from the viewpoint of the film formation state, connection reliability, and the like. .

  The liquid epoxy resin is not particularly limited as long as it has fluidity at room temperature, and all commercially available epoxy resins can be used. Specific examples of such epoxy resins include naphthalene type epoxy resins, biphenyl type epoxy resins, phenol novolac type epoxy resins, bisphenol type epoxy resins, stilbene type epoxy resins, triphenolmethane type epoxy resins, phenol aralkyl type epoxy resins. Resins, naphthol type epoxy resins, dicyclopentadiene type epoxy resins, triphenylmethane type epoxy resins, and the like can be used. These may be used alone or in combination of two or more. Moreover, you may use it combining suitably with other organic resins, such as an acrylic resin.

  As the latent curing agent, various curing agents such as a heat curing type and a UV curing type can be used. The latent curing agent does not normally react but is activated by some trigger and starts the reaction. The trigger includes heat, light, pressurization, etc., and can be selected and used depending on the application. In particular, in the present embodiment, a thermosetting latent curing agent is preferably used, and is fully cured by being heated and pressed by the P-type electrode terminal portion 9 and the N-type electrode terminal portion 10. When a liquid epoxy resin is used, a latent curing agent made of imidazoles, amines, sulfonium salts, onium salts, or the like can be used.

  As the silane coupling agent, epoxy, amino, mercapto sulfide, ureido, and the like can be used. Among these, in this Embodiment, an epoxy-type silane coupling agent is used preferably. Thereby, the adhesiveness in the interface of an organic material and an inorganic material can be improved.

  Moreover, it is preferable to contain an inorganic filler as another additive composition. By containing an inorganic filler, the fluidity of the resin layer during pressure bonding can be adjusted, and the particle capture rate can be improved. As the inorganic filler, silica, talc, titanium oxide, calcium carbonate, magnesium oxide and the like can be used, and the kind of the inorganic filler is not particularly limited.

  FIG. 3 is a diagram schematically showing a laminate 22 in which the tab wire 20 and the conductive adhesive film 23 are laminated. The conductive adhesive film 23 is formed in a tape shape by laminating a binder resin layer 24 on a release substrate 27. The tape-like conductive adhesive film 23 is wound and laminated on a reel 26 so that the peeling base material 27 is on the outer peripheral side. There is no restriction | limiting in particular as the peeling base material 27, PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methlpentene-1), PTFE (Polytetrafluoroethylene) etc. can be used.

  As for the conductive adhesive film 23, the above-mentioned tab wire 20 is stuck on the binder resin layer 24 as a cover film. That is, in the conductive adhesive film 23, the binder resin layer 24 is laminated on the one surface 20 a of the tab wire 20 of the positive electrode tab wire 11 or the negative electrode tab wire 15. Thus, by previously laminating and integrating the tab wire 20 and the conductive adhesive film 23, the peeling base material 27 is peeled off in actual use, and the binder resin layer 24 of the conductive adhesive film 23 is removed. By sticking on the P-type electrode terminal portion 9 or the N-type electrode terminal portion 10, the positive electrode tab wire 11 or the negative electrode tab wire 15 and the electrode terminal portions 9 and 10 are temporarily attached.

  The conductive adhesive film 23 described above dissolves the conductive particles 25, the film-forming resin, the liquid epoxy resin, the latent curing agent, and the silane coupling agent in a solvent. As the solvent, toluene, ethyl acetate or the like, or a mixed solvent thereof can be used. The solution for resin production obtained by dissolving is applied on the peeling substrate 27 and the solvent is volatilized to obtain the conductive adhesive film 23. Thereafter, the conductive adhesive film 23 is attached to the one surface 20 a of the tab wire 20. Thereby, the laminated body 22 in which the electroconductive adhesive film 23 was provided over the whole surface of the one surface 20a of the tab wire 20 is formed.

  Such a conductive adhesive film 23 is obtained by temporarily bonding the positive electrode tab wire 11 and the negative electrode tab wire 15 onto the P-type electrode terminal portion 9 or the N electrode terminal portion 12, and then using a heating press head or a vacuum laminator. Hot pressing is performed at a predetermined temperature and pressure. Thereby, in the conductive adhesive film 23, the binder resin flows out from between the P-type electrode terminal portion 9 and the positive electrode current collecting tab portion 12 and between the N-type electrode terminal portion 10 and the negative electrode current collecting tab portion 16. In addition, the conductive particles 25 are sandwiched between the current collecting tab portions 12 and 16 and the electrode terminal portions 9 and 10, and the binder resin is cured in this state. As a result, the conductive adhesive film 23 bonds the current collecting tab portions 12 and 16 onto the electrode terminal portions 9 and 10 and connects the current collecting tab portions 12 and 16 and the electrode terminal portions 9 and 10 together. Conductive connection can be established.

  The positive electrode tab wire 11 and the negative electrode tab wire 15 are an adhesive layer for connecting the P-type electrode terminal portion 9 and the positive electrode tab wire 11 and connecting the N-type electrode terminal portion 10 and the negative electrode tab wire 15. In addition to the conductive adhesive film 23 described above, an insulating adhesive film can be used as 21. The insulating adhesive film has the same configuration as the conductive adhesive film except that the binder resin layer does not contain conductive particles.

[Manufacturing process of thin film solar cell module]
Subsequently, the manufacturing process of the thin film solar cell module 6 mentioned above is demonstrated. As shown in FIG. 5, the manufacturing process of the thin film solar cell module 6 includes the manufacturing process (step 1) of the thin film solar cell 1, the P-type electrode terminal portion 9 and the N-type electrode terminal 10 of the thin-film solar cell 1. A step of arranging the laminated body 22 (step 2), a step of connecting the ammeter A or the voltmeter V to the tab wire 20 of the laminated body 11 and measuring the output characteristics of the thin-film solar cell 1 (step 3), and the output It has the process (step 4) which determines the grade of the thin film solar cell 1 based on a result, and the process (step 5) which modularizes the thin film solar cell 1 according to a grade.

  The thin film solar cell 1 is manufactured by a normal method. In the thin film solar cell 1, a laminate 22 is disposed on the P-type electrode terminal portion 9 and the N-type electrode terminal 10 (FIG. 1). The laminated body 22 is pulled out from the reel 26 by a predetermined length and cut, and then the peeling base material 27 is peeled off, and the exposed conductive adhesive film 23 is formed into the P-type electrode terminal portion 9 and the N-type electrode terminal 10. It is arranged on the top and pressed from above the tab line for a predetermined time by a bonder or the like. Thereby, the positive electrode tab wire 11 and the negative electrode tab wire 15 (tab wire 20) are provided on the P-type electrode terminal portion 9 and the N-type electrode terminal 10 through the conductive adhesive film 23, respectively.

  The thin film solar cell 1 to which the positive electrode tab wire 11 and the negative electrode tab wire 15 are connected is measured for power characteristics, and graded according to output characteristics. For example, it is graded into a thin film solar cell 1 for a high-quality solar cell module with good output characteristics and a thin film solar cell 1 for an ordinary solar cell module whose output characteristics meet a predetermined standard but does not reach a good level. Is done.

  The output characteristics are measured by connecting an ammeter A or a voltmeter V to the connecting tab portions 13 and 17 ahead of the current collecting tab portions 12 and 16 of the positive electrode tab wire 11 and the negative electrode tab wire 15 via the cable 29, By irradiating the surface of the thin film solar cell 1 with predetermined pseudo sunlight, the electrical characteristics of the thin film solar cell 1 can be measured.

  At this time, by using the connection tab portions 13 and 17 of the positive electrode tab wire 11 and the negative electrode tab wire 15 as measurement terminals, power characteristics can be easily measured without using a dedicated measurement jig. In addition, by using the connection tab portions 13 and 17 as measurement terminals, when a dedicated measurement jig is used, it is necessary to consider the influence of output reduction due to the shadow of the jig. There is no need to consider the effects of shadows. When the connection tab portions 13 and 17 are used as measurement terminals, it is necessary to consider the resistance of the connection tab portions 13 and 17, but the resistance value of the tab wire 20 is known. It is easy to correct the current value and the voltage value by using 17. On the other hand, correcting the influence of the output reduction due to the shadow of the measuring jig is complicated in calculation and inaccurate.

  Thereafter, the thin-film solar cell 1 is graded according to output characteristics, such as high quality or normal quality, and is transferred to a modularization process for each grade. In the modularization process, the thin film solar cells 1 are arranged for each grade to form a solar cell string via the positive electrode tab wire 11 and the negative electrode tab wire 15, or the thin film solar cell 1 is modularized alone. In the thin film solar cell 1 or the solar cell string, a sheet 3 and a back sheet 4 of a sealing adhesive are laminated on the back surface, and are collectively laminated and sealed by a vacuum laminator or the like. At this time, the connection tab portions 13 and 17 are inserted through the insertion holes provided in the sheet 3 and the back sheet 4 of the sealing adhesive, and are connected to the terminal box 19 disposed on the back sheet 4 (see FIG. 2).

  As described above, the thin film solar cell 1 uses the connection tab portions 13 and 17 connected to the terminal box 19 as the measurement terminals for the power characteristics, thereby continuously performing the measurement of the power characteristics, grading, and modularization. be able to. Therefore, according to such a method for manufacturing a solar cell module, the manufacturing process can be made efficient without using a dedicated jig for measuring the output characteristics of the solar cell.

[Silicon solar cells]
In addition, although the case where the thin film solar cell 1 was used as an example was described above as a solar cell, current collection, measurement, and cell connection are similarly performed using a tab wire when a silicon-based solar cell is used. it can.

  For example, as shown in FIGS. 6 and 7, a silicon-based solar battery cell 30 in which a plurality of finger electrodes 31 extending between opposite side edges of the light receiving surface are arranged in parallel intersects with all the finger electrodes 31. Tab wire 32 is connected via adhesive layer 33. The tab line 32 is connected to the light receiving surface of the solar battery cell 30 and connected to the finger electrode 31 and the back electrode 37 in the same manner as the positive electrode tab line 11 and the negative electrode tab line 15 described above, When measuring the power characteristics of the solar cell 30, it becomes a measurement terminal connected to the ammeter A or the voltmeter V, and in the subsequent modularization, the electrode of the adjacent solar cell 30 or the adjacent solar cell 30 is connected. It has the connection tab part 36 connected with the tab line 32 provided.

  As the adhesive layer 33, the conductive adhesive film 23 or an adhesive paste can be used for the adhesive layer 33 as described above. In addition, the conductive adhesive film 23 may be previously laminated on both sides of the tab wire 32 and may be collectively attached to the solar battery cell 30, or may be formed separately from the tab wire 32 and separately attached to the solar battery cell 30. May be.

  The current collecting tab portion 35 has substantially the same length as one side of the solar battery cell 30 orthogonal to the longitudinal direction of the finger electrode, and is electrically connected to the finger electrode 31 by the adhesive layer 33. The connection tab part 36 is a part ahead of the current collection tab part 35, and is conductively connected to the finger electrode 31 and the back electrode 37 of the adjacent solar battery cell 30 by the adhesive layer 33, or is adjacent to the solar battery cell 30. Are connected to the connecting portion tab portion 36 of the tab wire 32 similarly provided. As a result, the solar battery cell 30 constitutes a string 34, and the string 34 is sandwiched between the sheets 3 of the sealing adhesive, and the front cover 5 provided on the light receiving surface side and the back sheet 4 provided on the back surface side. The solar cell module 38 is formed by laminating together. Note that the solar cell module 38 is appropriately attached with a metal frame 7 such as aluminum around it.

[Manufacturing process of silicon-based solar cell module]
Next, the manufacturing process of the silicon-based solar cell module 38 described above will be described. Similar to the manufacturing process of the thin-film solar battery module, the manufacturing process of the silicon-based solar battery module 38 is similar to the manufacturing process of the thin-film solar battery module, as shown in FIG. A step of placing the tab wire 32 on the finger electrode 31 and the back electrode 37 (step 2), and a step of measuring the output characteristics of the solar battery cell 30 by connecting the ammeter A or the voltmeter V to the tab wire 32 ( Step 3), a step of determining the grade of the solar battery cell 30 based on the output result (Step 4), and a step of modularizing the solar battery cell 30 according to the grade (Step 5).

  The silicon-based solar battery cell 30 is manufactured by a normal method. In the solar battery cell 30, after the finger electrode 31 and the back electrode 37 are formed, the current collecting tab portion 35 of the tab wire 32 is attached to the light receiving surface and the back surface via the adhesive layer 33. In the following, a bus barless type solar cell 30 having no bus bar electrode will be described as an example, but the present invention can also be applied to a solar cell 30 having a bus bar electrode. As shown in FIG. 7A, for example, two tab wires 32 are pasted so as to intersect with all the finger electrodes 31 formed on the light receiving surface. Moreover, as shown in FIG.7 (b), two tab wires 32 are stuck by the predetermined position of the back surface electrode 37 formed in the back surface.

  Thereafter, the solar cell 30 is measured for power characteristics, and graded according to the output characteristics. For example, the solar cell 30 for a high-quality solar cell module having good output characteristics and the solar cell 30 for a normal solar cell module whose output characteristics satisfy a predetermined standard but are not good are classified. Is done.

  The output characteristics are measured by connecting an ammeter A or a voltmeter V to the connection tab portion 36 ahead of the current collecting tab portion 35 of the tab wire 32 via the cable 29, and applying predetermined pseudo-sunlight to the solar cell 30. By irradiating the surface, the electrical characteristics of the solar battery cell 30 can be measured by a so-called four-terminal method.

  At this time, by using the connection tab portion 36 of the tab wire 32 as the measurement terminal, the power characteristic can be easily measured without using a dedicated measurement jig. In addition, by using the connection tab portion 36 as a measurement terminal, when a dedicated measurement jig is used, it is necessary to consider the influence of the output decrease due to the shadow of the jig. There is no need to consider the impact. When the connection tab portion 36 is used as a measurement terminal, it is necessary to consider the resistance of the connection tab portion 36, but the resistance value of the tab wire 32 is known, and the current caused by passing through the connection tab portion 36 Correction of values and voltage values is easy. On the other hand, correcting the influence of the output reduction due to the shadow of the measuring jig is complicated in calculation and inaccurate. Furthermore, since the positive electrode tab wire 11 and the negative electrode tab wire 15 use metal foils, such as copper foil, as a base material and are stuck on the surface of the photovoltaic cell 30 via the electroconductive adhesive film 23, Following the unevenness of the finger electrodes 31, it is possible to evenly connect to all the finger electrodes 31, and accurate output characteristics can be measured.

  Thereafter, the solar cells 30 are graded according to output characteristics, such as high quality or normal quality, and transferred to a modularization process according to grade. In the modularization process, as shown in FIG. 8, the connection tab portion 36 used as the measurement terminal is directly connected to the connection tab portion 36 of the tab wire 32 attached to the adjacent solar battery cell 30 as an interconnector. The string 34 is formed by connecting with the finger electrode 31 and the back surface electrode 37 through the adhesive layer 33. The string 34 is composed of solar cells 30 of the same grade in advance, whereby a high quality solar cell module 38 and a normal quality solar cell module 38 can be manufactured. Next, the sealing adhesive sheet 3, the front cover 5, and the back sheet 4 are laminated on the front and back surfaces of the string 34, and are collectively laminated and sealed with a vacuum laminator or the like to form the solar cell module 38. Note that the solar cell module 38 is appropriately attached with a metal frame 7 such as aluminum around it (FIG. 6).

  As described above, even in the silicon-based solar battery, by using the connection tab portion 36 connected to the adjacent solar battery cell 30 as the power characteristic measurement terminal, the measurement from the power characteristic, grading to modularization is continuously performed. Can be done. Therefore, according to the manufacturing method of such a solar cell module, a manufacturing process can be made efficient. Furthermore, according to the present method, defective products discovered by grading are not applied to the modularization process, so that productivity can be improved as compared with the conventional method.

  In addition, when the bus bar electrode which cross | intersects the finger electrode 31 is formed in the light-receiving surface, a silicon-type solar cell connects the tab wire 32 via the adhesive layer 33 on this bus bar electrode. Also in this case, by using the connection tab portion 36 of the tab wire 32 as a measurement terminal, it is possible to efficiently perform from the measurement of power characteristics to modularization without using a dedicated measurement jig.

DESCRIPTION OF SYMBOLS 1 Thin film solar cell, 2 solar cell, 3 sheet | seat, 4 back sheet | seat, 6 solar cell module, 7 metal frame, 8 translucent insulating substrate, 9 P-type electrode terminal part, 10 N-type electrode terminal part, 11 For positive electrodes Tab wire, 12 Positive current collecting tab portion, 13 Positive electrode connecting tab portion, 14 Folded portion, 15 Negative electrode tab wire, 16 Negative electrode current collecting tab portion, 17 Negative electrode connecting tab portion, 18 Folded portion, 19 Terminal box, 20 Tab wire , 21 Adhesive layer, 23 Conductive adhesive film, 24 Binder resin layer, 25 Conductive particles, 26 Reel, 27 Release substrate, 29 Cable, 30 Solar cell, 31 Finger electrode, 32 Tab wire, 33 Adhesive layer , 35 Current collecting tab part, 36 Connection tab part, 37 Back electrode, 38 Solar cell module

Claims (6)

A step of arranging a tab wire via an adhesive on the electrode of the solar cell;
Connecting the tab wire and a measuring instrument for measuring the output characteristics of the solar cell, and measuring the output characteristics of the solar cell;
A step of determining the grade of the solar cell according to the measurement result of the measuring device;
The manufacturing method of the solar cell module which has the process of modularizing the said solar cell for every grade.   2. The solar cell module according to claim 1, wherein in the modularization step, the solar cell is sealed with a sealing material and a protective material, and the tab wire inserted through the sealing material and the protective material is connected to a terminal box. Manufacturing method.   The method for manufacturing a solar cell module according to claim 1, wherein in the modularization step, the solar cells are arranged for each of the determined grades, and a string is formed through the tab wire.   The method for manufacturing a solar cell module according to claim 1, wherein the adhesive is molded into a film shape and laminated in advance on a connection surface of the tab wire to the solar cell.   The method for manufacturing a solar cell module according to claim 2, wherein the solar cell is a thin film solar cell.   The method for manufacturing a solar cell module according to claim 3, wherein the solar cell is a crystalline silicon solar cell and has a bus bar-less structure.

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