JP6705517B2 - Method for manufacturing solar cell module - Google Patents

Description

The present invention relates to a method for manufacturing a solar cell module.

Since the solar cell module is a device that directly converts light energy into electric energy, it has attracted attention as a clean energy, and its market is expected to expand rapidly in the future. Such a solar battery module generally has a structure in which a plurality of solar battery cells are connected in series according to a required voltage value.

More specifically, in the solar cell module, the front surface electrode formed on the light receiving surface side of the solar cell and the back surface electrode formed on the back surface side of the adjacent solar cell are connected by a wiring member such as a tab wire. It is electrically connected. Conventionally, soldering has been used for connecting these electrodes and tab wires because they have excellent connection reliability such as conductivity and fixing strength, are inexpensive and have high versatility (for example, see Patent Document 1). ..

JP, 2005-236235, A

In recent years, from the viewpoint of environmental protection, a method of connecting electrodes of solar cells and tab wires by using, for example, a film adhesive without using solder has been studied. The connection method using the adhesive film enables connection at a lower temperature than the connection using solder. Therefore, it is possible to suppress cracking/warping of the solar cells due to high temperature at the time of connection and volume contraction of the solder.

On the other hand, in the conventional connection method using an adhesive film, at the time of connection, the solar battery cell in which the tab wire is arranged via the adhesive film is thermocompression-bonded with a pressure head at a pressure of about 2.0 MPa. ing. In such a conventional method, the solar cell may be cracked by the shearing force at the time of pressure bonding. As a method of connecting the solar cell and the tab wire at a low pressure, there is also a method of increasing the fluidity of the adhesive and enhancing the excluding property of the resin at the time of pressure bonding. However, in this method, the tackiness of the surface of the adhesive film becomes excessive, and blocking (a phenomenon in which the adhesive is transferred to the back surface of the substrate) may occur in a state where the adhesive film is wound into a roll.

The present invention has been made to solve the above problems, and provides a method for manufacturing a solar cell module capable of preventing cracking of the solar cell when connecting the solar cell and the tab wire and realizing good connection. The purpose is to do.

In order to solve the above problems, a method for manufacturing a solar cell module according to the present invention is a method for manufacturing a solar cell module in which finger electrodes arranged on a light-receiving surface of a solar cell and tab lines are connected using an adhesive film. However, the light-receiving surface of the solar cell is not provided with a bus bar electrode connecting between the finger electrodes, the tab wire arrangement region on the finger electrode, the tab wire is arranged via an adhesive film, A pressure member having a width wider than the width of the tab wire is arranged in the hot air supply unit for supplying the hot air, and while the hot air is supplied by the hot air supply unit, the pressure member is 1.0 MPa or less in the area where the tab wire is arranged. The feature is that the tab wire is thermocompression bonded by applying pressure.

In this solar cell module manufacturing method, in a so-called bus bar electrodeless solar cell, the tab wire is directly connected to the finger electrode via the adhesive film. In this method, when pressure is applied to the tab wire from the pressing member, the adhesive film is pressed against the uneven surface formed by the finger electrodes arranged on the light receiving surface. Therefore, even if the pressing member having a width wider than the width of the tab wire is pressed uniformly and at a low pressure of 1.0 MPa or less, the resin excluding property during the pressure bonding can be sufficiently ensured, and the crack of the solar battery cell can be prevented. It is possible to realize a good connection while preventing the above. Further, in this method of manufacturing a solar cell module, the pressing member is arranged in the hot air supply unit that supplies hot air. Therefore, the pressure member can be uniformly heated by the hot air supply unit, so that the adhesive film can be suitably cured.

Further, the method for manufacturing a solar cell module according to the present invention is a method for manufacturing a solar cell module in which finger electrodes arranged on the light-receiving surface of a solar cell and tab wires are connected using an adhesive film, On the light-receiving surface of the battery cell, a bus bar electrode that connects the finger electrodes is provided with a width narrower than the width of the adhesive film, and the tab wire is placed in the area where the tab wire is placed on the bus bar electrode via the adhesive film. Is arranged, and a pressurizing member having a width wider than the line width of the tab wire is arranged in the hot air supply section for supplying the hot air, and while the hot air is supplied by the hot air supply section, the pressing member is arranged in the arrangement area of the tab wire. The feature is that the tab wire is thermocompression bonded by applying a pressure of 1.0 MPa or less.

In this solar cell module manufacturing method, in a solar cell having a busbar electrode having a width narrower than the width of the adhesive film, the tab wire is connected to the busbar electrode via the adhesive film. In this method, when pressure is applied to the tab wire from the pressing member, the adhesive film is locally pressed by the bus bar electrode having a width narrower than that of the adhesive film. Therefore, even if the pressing member having a width wider than the width of the tab wire is pressed uniformly and at a low pressure of 1.0 MPa or less, the resin excluding property during the pressure bonding can be sufficiently ensured, and the crack of the solar battery cell can be prevented. It is possible to realize a good connection while preventing the above. Further, in this method of manufacturing a solar cell module, the pressing member is arranged in the hot air supply unit that supplies hot air. Therefore, the pressure member can be uniformly heated by the hot air supply unit, so that the adhesive film can be suitably cured.

Further, the method for manufacturing a solar cell module according to the present invention is a method for manufacturing a solar cell module in which finger electrodes arranged on the light-receiving surface of a solar cell and tab wires are connected using an adhesive film, On the light receiving surface of the battery cell, a bus bar electrode connecting between the finger electrodes is provided only on the end side of the light receiving surface with a width narrower than the width of the adhesive film. In the area where the tab wire is arranged, the tab wire is arranged via the adhesive film so as to at least partially overlap the bus bar electrode, and the hot air supply unit that supplies hot air is pressed with a width wider than the width of the tab wire. It is characterized in that the members are arranged, and while the hot air is supplied by the hot air supply unit, a pressure member applies a pressure of 1.0 MPa or less to the arrangement region of the tab wires to thermocompress the tab wires.

In this method of manufacturing a solar cell module, the tab wire is directly connected to the finger electrode via the adhesive film. In this method, when pressure is applied to the tab wire from the pressing member, the adhesive film is pressed against the uneven surface formed by the finger electrodes arranged on the light receiving surface. Therefore, even if the pressing member having a width wider than the width of the tab wire is pressed uniformly and at a low pressure of 1.0 MPa or less, the resin excluding property during the pressure bonding can be sufficiently ensured, and the crack of the solar battery cell can be prevented. It is possible to realize a good connection while preventing the above. Further, in this method of manufacturing a solar cell module, the pressing member is arranged in the hot air supply unit that supplies hot air. Therefore, the pressure member can be uniformly heated by the hot air supply unit, so that the adhesive film can be suitably cured. Furthermore, in this method of manufacturing a solar cell module, the bus bar electrodes connecting the finger electrodes are provided only on the end side of the light receiving surface with a width narrower than the width of the adhesive film. Thereby, the bus bar electrode can be used as an alignment mark when arranging the tab lines. In addition, since the bus bar electrodes can collect current from the finger electrodes at the ends of the light receiving surface, it is possible to avoid a decrease in the power collection efficiency of the solar cell module.

Further, it is preferable to arrange the tab wires so as to extend over all the finger electrodes on the light receiving surface. With this configuration, current can be collected from all the finger electrodes, and the current collection efficiency of the solar cell module can be sufficiently secured.

It is preferable that the finger electrodes have a thickness of 10 μm to 30 μm and a width of 5 μm to 90 μm. When the thickness/width of the finger electrode satisfies this range, the uneven surface formed by the finger electrode is sufficiently formed. Therefore, it is possible to more sufficiently ensure the excluding property of the resin at the time of pressure bonding.

Further, the ratio of the thickness of the finger electrodes to the thickness of the adhesive film is preferably in the range of 1:5 to 6:5. In this range, it is possible to more sufficiently secure the resin excluding property at the time of pressure bonding by the uneven surface formed by the finger electrodes.

The width of the bus bar electrode is preferably 90 μm or less. In this way, by reducing the width of the bus bar electrode, the adhesive film is pressed more locally by the bus bar electrode, so that it is possible to more sufficiently secure the resin excluding property during the pressure bonding.

Further, it is preferable that the bus bar electrode has a thickness of 10 μm to 30 μm and a width of 5 μm to 90 μm. In this case, since the adhesive film is more locally pressed by the bus bar electrode, it is possible to more sufficiently secure the excluding property of the resin at the time of pressure bonding.

Moreover, it is preferable to apply a pressure of 0.5 MPa or less to the arrangement region of the tab wire to thermocompress the tab wire. By further lowering the pressure applied to the area where the tab wire is arranged, cracking of the solar cell can be prevented more reliably.

Further, it is preferable to use a conductive adhesive film or an insulating adhesive film as the adhesive film. Thereby, the connection of the tab wire can be favorably realized.

According to the method for manufacturing a solar battery module of the present invention, it is possible to prevent cracking of the solar battery cell when connecting the solar battery cell and the tab wire, and realize good connection.

It is a schematic perspective view which shows the solar cell module manufactured using the manufacturing method of the solar cell module which concerns on 1st Embodiment of this invention. It is the schematic plan view which looked at the solar cell which comprises the solar cell module of FIG. 1 from the light-receiving surface side. It is the schematic plan view which looked at the solar cell of FIG. 2 from the back surface side. It is a schematic sectional drawing which shows the mode of connection of a photovoltaic cell and a tab wire. It is a schematic plan view which looked at the solar cell which applied the manufacturing method of the solar cell module which concerns on 2nd Embodiment of this invention from the light-receiving surface side. It is a schematic sectional drawing which shows the mode of connection of a photovoltaic cell and a tab wire. It is a schematic sectional drawing which shows another example of the mode of connection of a photovoltaic cell and a tab wire. It is the schematic plan view which looked at the photovoltaic cell which concerns on a modification from the light-receiving surface side. It is a figure which shows the result of the effect confirmation test which concerns on an Example. It is a figure which shows the result of the effect confirmation test which concerns on a comparative example.

Hereinafter, preferred embodiments of a method for manufacturing a solar cell module according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing a solar cell module manufactured by using the method for manufacturing a solar cell module according to the first embodiment of the present invention. As shown in the figure, the solar battery module 1 is configured by electrically connecting a plurality of solar battery cells 2 to each other by a tab wire 3.

One surface side of the solar cell 2 is a light receiving surface 2a on which a front surface electrode is formed, and the other surface side of the solar cell 2 is a back surface 2b on which a back surface electrode is formed. Between adjacent solar cells 2 and 2, the front surface electrode on the light receiving surface 2a side and the back surface electrode on the back surface 2b side are connected by a tab wire 3, whereby a string in which the solar battery cells 2 are connected in series is formed. Are formed.

The solar cell module 1 as a product includes, for example, a matrix in which a plurality of strings are arranged. The solar cell module 1 is laminated together with the front cover on the side of the light receiving surface 2a for protection and the back sheet on the side of the back surface 2b in a state where the matrix is sandwiched by adhesive sheets for sealing, and aluminum or the like is provided around the periphery. Complete by attaching the metal frame of.

As the sealing adhesive, a translucent adhesive such as ethylene vinyl alcohol (EVA) resin is used. Further, a material having a light-transmitting property such as glass is used for the surface cover, and a laminated body in which glass or aluminum foil is sandwiched between resin films is used for the back sheet.

Next, the method for manufacturing the solar cell module 1 will be described in more detail. In the description, first, the configuration of the solar battery cell 2 will be described. FIG. 2 is a schematic plan view showing the light receiving surface side of the solar battery cell, and FIG. 3 is a schematic plan view showing the back surface side of the solar battery cell. As shown in FIGS. 2 and 3, the solar battery cell 2 has a substrate 11.

The substrate 11 is formed in, for example, at least one of Si single crystal, polycrystal, and amorphous into a substantially square shape, and the four corners of the substrate 11 are chamfered in an arc shape. One surface of the substrate 11 corresponds to the light receiving surface 2a of the solar cell 2, and the other surface of the substrate 11 corresponds to the back surface 2b of the solar cell 2. The substrate 11 may be an n-type semiconductor or a p-type semiconductor on the light receiving surface 2a side.

As shown in FIG. 2, a plurality of finger electrodes 12 are provided as surface electrodes on the light receiving surface 2a side of the substrate 11. The finger electrodes 12 are formed on substantially the entire light receiving surface 2a of the substrate 11 in a direction substantially orthogonal to the extending direction of the strings of the solar cell module 1, and are arranged at predetermined intervals along the extending direction of the strings. There is.

The finger electrodes 12 are formed by applying and heating a metal paste, for example. The thickness of the finger electrode 12 is, for example, 10 μm to 30 μm, and the width of the finger electrode 12 is, for example, 5 μm to 90 μm. The distance between the adjacent finger electrodes 12, 12 is, for example, about 2 mm.

The material for forming the finger electrodes 12 is formed by a glass paste containing silver, a silver paste in which various conductive particles are dispersed in an adhesive resin, a gold paste, a carbon paste, a nickel paste, an aluminum paste, and baking/vapor deposition. Examples thereof include ITO. Among these, it is preferable to use a glass paste containing silver from the viewpoints of heat resistance, conductivity, stability, and cost.

As shown in FIG. 3, a bus bar electrode 13 and a back surface electrode 14 are provided on the back surface 2b side of the substrate 11. The bus bar electrodes 13 are provided in a pair of straight lines at positions corresponding to the placement regions P, P of the tab wires 3 on the light receiving surface 2a side. Similar to the finger electrodes 12, the bus bar electrodes 13 are formed by applying and heating a metal paste, for example. The width of the bus bar electrode 13 is, for example, about 2 mm.

The back surface electrode 14 is formed by baking aluminum paste, for example. It is formed over the entire area of the back surface 2b side of the substrate 11 except the portion where the bus bar electrode 13 is formed. On the back surface 2b side, the arrangement regions P, P of the pair of tab lines 3 are set along the bus bar electrode 13. The tab wire 3 is connected to the bus bar electrode 13 and the back surface electrode 14 via an adhesive film 15. The arrangement region P is set linearly over substantially the entire length of the bus bar electrode 13, for example.

Next, the adhesive film 15 (see FIG. 4) used for connecting the tab wires 3 will be described.

The conductive adhesive used for the adhesive film 15 is, for example, 25 parts by mass of a film-forming resin, 20 parts by mass of a thermosetting resin, 55 parts by mass of a curing agent for a thermosetting resin, and 10 parts by mass of silicone particles. , 10 parts by mass of conductive particles are contained.

As the film-forming resin, a thermoplastic polymer such as a phenoxy resin, a polyester resin, and a polyamide resin is used from the viewpoint that a good film can be formed. Among these resins, it is preferable to use a phenoxy resin. The weight average molecular weight of the thermoplastic polymer is preferably 10,000 to 10,000,000 in consideration of the fluidity of the adhesive film 15.

Examples of the thermosetting resin include epoxy resin, polyimide resin, unsaturated polyester resin, polyurethane resin, bismaleimide resin, triazine-bismaleimide resin, and phenol resin. Among these resins, epoxy resin is preferably used in consideration of heat resistance.

The curing agent for thermosetting resin refers to a material that accelerates curing of the thermosetting resin when heated together with the thermosetting resin. Such curing agents include imidazole-based curing agents, hydrazide-based curing agents, amine-based curing agents, phenol-based curing agents, acid anhydride-based curing agents, boron trifluoride-amine complexes, sulfonium salts, iodonium salts, and polyamine salts. , Amine imides, and dicyandiamide are used. When an epoxy resin is used as the thermosetting resin, it is preferable to use an imidazole curing agent, a hydrazide curing agent, a boron trifluoride amine complex, a sulfonium salt, an amine imide, a polyamine salt, and dicyandiamide.

As the silicone particles, silicone rubber particles, silicone resin particles, silicone composite particles and the like are used. The silicone rubber particles are, for example, silicone rubber particles having a structure in which linear dimethylpolysiloxane is crosslinked. The silicone resin particles are particles of a cured polyorganosilsesquioxane having a structure in which siloxane bonds are crosslinked in a three-dimensional network represented by (RSiO3/2)n.

Examples of the conductive particles include gold particles, silver particles, copper particles, nickel particles, gold-plated nickel particles, gold/nickel-plated plastic particles, copper-plated particles, and nickel-plated particles. From the viewpoint of ensuring conductivity, the average particle diameter of the conductive particles is preferably 1 μm to 20 μm, and more preferably 1 μm to 5 μm.

Further, the conductive adhesive may contain a coupling agent for improving the adhesiveness and wettability with the adherend. Examples of the coupling agent include silane coupling agents and titanate coupling agents.

In a solar cell without a bus bar electrode, such as the solar cell 2 described above, since the tab wire 3 and the finger electrode 12 are directly connected, conductive particles of 5 μm or more exist on the finger electrode 12. It is also conceivable that the conduction between the tab wire 3 and the finger electrode 12 is hindered. Therefore, instead of the conductive adhesive, the adhesive film 15 using an insulating adhesive containing no conductive particles may be used. In this case, it is possible to suppress the occurrence of defective conduction between the tab wire 3 and the finger electrode 12 as described above.

In forming the adhesive film 15, a resin composition obtained by dissolving the above film-forming resin, thermosetting resin, curing agent, conductive particles and the like in a solvent is applied to a release substrate by using a bar coater or a coating device. To do. Then, the composition on the release substrate is dried by using a hot oven or a heat drying device to obtain the adhesive film 15 having a predetermined size.

The thickness of the adhesive film 15 is appropriately set in consideration of the relationship with the thickness of the finger electrodes 12. The thickness of the adhesive film 15 is set such that the ratio of the thickness of the finger electrodes 12 to the thickness of the adhesive film 15 is in the range of 1:5 to 6:5. The width of the adhesive film 15 is set to be smaller than the width of the tab wire 3. The width of the adhesive film 15 is set to about 1.2 mm when the width of the tab wire 3 is about 1.5 mm, for example.

Next, a method of connecting the solar battery cells 2 and the tab wires 3 will be described. FIG. 4 is a schematic cross-sectional view showing how the solar cells are connected to the tab wires. In the same drawing, a cross section obtained by cutting the arrangement region P of the tab wire 3 in the longitudinal direction is shown.

As shown in FIG. 4, when connecting the solar cell 2 and the tab wire 3, first, the light receiving surface 2a is set on the stage S with the light receiving surface 2a facing upward. Next, the adhesive film 15 is attached along the arrangement area P of the tab wire 3 on the light receiving surface 2a side, and the tab wire 3 is temporarily fixed on the adhesive film 15. As the tab wire 3, for example, a copper ribbon whose surface is covered with solder and has a width of about 1.5 mm is used, but the tab wire 3 is not limited to this, and the surface may not be covered with solder.

After the tab wire 3 is temporarily fixed, the tab wire 3 and the solar cell 2 are thermocompression bonded by using, for example, a thermocompression bonding machine K. The thermocompression bonding machine K includes a flat plate-shaped pressing member 21 facing the solar battery cells 2 and a hot air supply nozzle (hot air supply unit) 22 that supplies hot air toward the solar battery cells 2.

The width of the pressure member 21 is wider than the width of the tab wire 3. By making the width of the pressing member 21 wider than the width of the tab wire 3, the pressure applied to the arrangement area P of the tab wire 3 is made uniform. Further, the hot air supply nozzles 22 are arranged at predetermined intervals along the longitudinal direction of the adhesive film 15. The pressurizing member 21 is arranged in a direction along the arrangement direction of the hot air supply nozzles 22, and is supported by the support member 23 from the discharge port of the hot air supply nozzle 22 at a predetermined interval. The hot air discharged from the discharge port of the hot air supply nozzle 22 heats the connection position of the pressing member 21 and the tab wire 3.

By applying the pressure, the adhesive film 15 is pressed against the uneven surface formed by the finger electrodes 12 arranged on the light receiving surface 2a. By such pressing on the uneven surface, the resin of the adhesive film 15 is sufficiently removed at the time of pressure bonding, and the connection between the finger electrode 12 and the tab wire 3 is excellently realized. At the time of thermocompression bonding, the temperature of the pressing member 21 is set to about 80° C. to 320° C. both above and below, and pressure is applied so that the pressure applied to the arrangement region P of the tab wire 3 is 1.0 MPa or less. The time for applying pressure is preferably about 1 second to 30 seconds. The applied pressure is more preferably 0.5 MPa or less.

At the time of thermocompression bonding, hot air is blown to the adhesive film 15 to accelerate the curing of the adhesive. The hot air from the hot air supply nozzle 22 heats the pressure member 21 together with the adhesive film 15. Therefore, the adhesive film 15 can be suitably cured. The temperature of the hot air is preferably higher than the curing temperature of the adhesive film 15, and is set to, for example, about 80°C to 320°C. The hot air blowing time is preferably about 1 second to 50 seconds, for example. Since a plurality of hot air supply nozzles are arranged along the longitudinal direction of the adhesive film 15, the curing uniformity of the adhesive film 15 can be improved. The solar cell module 1 shown in FIG. 1 is obtained by performing the same process on the back surface 2b side of the solar cell 2 and connecting the tab wire 3 on the back surface 2b side.

As described above, in this solar cell module manufacturing method, in the so-called bus bar electrodeless solar cell 2, the tab wire 3 is directly connected to the finger electrode 12 via the adhesive film 15. In this method, when pressure from the pressure member 21 is applied to the tab wire 3, the adhesive film 15 is pressed against the uneven surface formed by the finger electrodes 12 arranged on the light receiving surface 2a. Therefore, even if the pressing member 21 having a width wider than the width of the tab wire 3 is pressed uniformly and at a low pressure of 1.0 MPa or less, sufficient excluding property of the resin of the adhesive film 15 is secured at the time of pressure bonding. Therefore, good connection can be realized while preventing cracking of the solar battery cells 2. Further, in this method of manufacturing a solar cell module, the pressing member 21 is arranged in the hot air supply nozzle 22 that supplies hot air. Therefore, the pressure member 21 can be uniformly heated by the hot air supply nozzle 22, so that the adhesive film 15 can be suitably cured.

In the present embodiment, the finger electrode 12 has a thickness of 10 μm to 30 μm and a width of 5 μm to 90 μm. Further, the ratio of the thickness of the finger electrodes 12 to the thickness of the adhesive film 15 is in the range of 1:5 to 6:5. By satisfying such a range, the uneven surface formed by the finger electrodes 12 is sufficiently formed on the adhesive film 15. Therefore, it is possible to more sufficiently ensure the excluding property of the resin at the time of pressure bonding.
[Second Embodiment]

FIG. 5 is a schematic plan view showing a light receiving surface side of a solar battery cell to which the method for manufacturing a solar battery module according to the second embodiment of the present invention is applied. As shown in the figure, the second embodiment is different from the first embodiment in that a bus bar electrode 33 connecting between the finger electrodes 12 is provided on the light receiving surface 32a side of the solar cell 32.

The bus bar electrode 33 is linearly provided along the arrangement region P of the tab wire 3 so as to extend over all the finger electrodes 12 on the light receiving surface 32a and substantially orthogonal to the finger electrodes 12. The bus bar electrode 33 is formed by applying and heating a metal paste similarly to the bus bar electrode 13 on the back surface 2b side. The thickness of the bus bar electrode 33 is, for example, 10 μm to 30 μm. The width of the bus bar electrode 33 is smaller than the width of the bus bar electrode 13, and is, for example, 90 μm or less, preferably 5 μm to 90 μm.

Also in the second embodiment, after the tab wire 3 is temporarily fixed, the tab wire 3 and the solar cell 2 are thermocompression bonded by using, for example, a thermocompression bonding machine K, as shown in FIG. 6. FIG. 6 shows a cross section of the placement region P of the tab wire 3 cut in a direction orthogonal to the longitudinal direction. As shown in the figure, by performing thermocompression bonding using a pressing member 21 having a width wider than the width of the tab wire 3, as in the case of the first embodiment, the tab wire 3 is added to the arrangement area P. The pressure uniformity can be increased.

Further, by applying the pressure, the adhesive film 15 is locally pressed by the bus bar electrode 33 having a width narrower than that of the adhesive film 15. By such local pressing, the resin of the adhesive film 15 is sufficiently removed at the time of pressure bonding, and the connection between the bus bar electrode 33 and the tab wire 3 is excellently realized. Furthermore, since the pressing member 21 is arranged in the hot air supply nozzle 22 that supplies hot air, the pressing member 21 can be uniformly heated by the hot air supply nozzle 22, and the adhesive film 15 can be suitably cured.

The present invention is not limited to the above embodiment, and various modifications can be applied. For example, although the adhesive film 15 is illustrated in the above embodiment, the adhesive is not limited to a film adhesive, and a paste adhesive may be used. Further, in the above-described embodiment, in the thermocompression bonding machine K, the pressing member 21 is provided on the tip side of the hot air supply nozzle 22 extending in the thickness direction of the solar cell 2, but it extends in the plane direction of the solar cell 2. The pressing member 21 may be provided on the tip side of the hot air supply nozzle 22.

Further, as shown in FIG. 7, in the thermocompression bonding machine K, the pressurizing member 21 is supported by the tips of the plurality of load pins 25 arranged at a predetermined interval, and the hot air supply nozzle ( You may arrange|position the hot air supply part) 26. Further, an elastic sheet 27 made of rubber or the like may be provided on the pressing surface of the pressing member 21 against the tab wire 3. By providing such an elastic sheet 27, the tab wire 3 can be protected during thermocompression bonding. The elastic sheet 27 may be applied in the form shown in FIG. 4 and the form according to the above-described modification.

Further, as in the solar battery cell 42 shown in FIG. 8, only a part of the finger electrodes 12 may be connected by the bus bar electrodes 43 on the light receiving surface 42a. In the example shown in FIG. 8, only some of the finger electrodes 12 located on the end side of the light receiving surface 42a are connected by the bus bar electrode 43 having the same width as in the second embodiment. Further, in the finger electrode 12 located on the center side of the light receiving surface 42a, the arrangement region P of the tab wire 3 is set so as to at least partially overlap the bus bar electrode 43.

Even in such a form, the adhesive film 15 is pressed against the uneven surface formed by the finger electrodes 12 arranged on the light receiving surface 42a. Therefore, even if the pressing member 21 having a width wider than the width of the tab wire 3 is pressed uniformly and at a low pressure of 1.0 MPa or less, sufficient excluding property of the resin of the adhesive film 15 is secured at the time of pressure bonding. Therefore, good connection can be realized while preventing cracks in the solar battery cells 42. Further, since the pressure member 21 is arranged in the hot air supply nozzle 22 for supplying the hot air, the pressure member 21 can be uniformly heated by the hot air supply nozzle 22 and the adhesive film 15 can be suitably cured.

Further, in this embodiment, the bus bar electrode 43 at the end of the light receiving surface 42a can be used as an alignment mark when the tab wire 3 is arranged, while the bus bar electrode 43 collects from the finger electrode 12 at the end of the light receiving surface 42a. You can charge. Therefore, it is possible to avoid a decrease in the current collection efficiency of the solar cell module 1.
[Example]

Examples of the present invention will be described below. In this example, the solar cell and the tab wire were connected by the method for manufacturing a solar cell module according to Examples 1 to 5 and Comparative Examples 1 to 3, and the presence or absence of cell cracking in the solar cell module and the connection reliability. The sex was evaluated.

An infrared camera was used to confirm the occurrence of cell cracks. After connecting the tab wire to the solar battery cell, a current of 5 A was passed to cause the solar battery cell to emit light and an image was acquired. In the range within 10 mm from both ends of the tab wire, the cell crack having a length of 50 μm or more and a width of 0.1 μm or more was not confirmed, and A was confirmed.

A solar simulator (WXS-2000S-20CH, AM1.5G manufactured by Wacom Denso Co., Ltd.) was used for evaluation of connection reliability. After connecting the tab wire to the solar battery cell, the fill factor of the solar battery module at the initial stage of connection was measured with a solar simulator, and the fill factor of 70 or more was A and the fill factor of less than 70 was B.
[Example 1]

In Example 1, 25 parts by mass of a phenoxy resin (PKHC manufactured by Union Carbide Co., Ltd.) and a resin in which acrylic rubber particles were dispersed in a bisphenol A type epoxy resin (containing 17% by mass of acrylic particles, epoxy equivalent: 220 to 240) were used. 10 parts by mass, 10 parts by mass of cresol novolac type epoxy resin (epoxy equivalent of 163-175), 10 parts by mass of silica fine particles KMP-605 (manufactured by Shin-Etsu Chemical Co., Ltd. average particle diameter 2 μm), conductive particles of nickel (Fukuda metal foil) Powder industry Co., Ltd. NiPF-BQ average particle size 5 μm 10 parts by mass, curing agent (Asahi Kasei Chemical Co., Ltd.: imidazole modified core is used as the core, and its surface is coated with polyurethane Microcapsules with average particle size 5 μm An adhesive film was prepared by blending 55 parts by mass of a masterbatch type curing agent obtained by dispersing a type curing agent in a liquid bisphenol F type epoxy resin).

Next, the peeled PET was coated with an adhesive film using a bar coater and dried in an oven at 80° C. for 5 minutes to prepare an adhesive film having a thickness of 25 μm. Then, the obtained adhesive film was cut into a width of 1.2 mm.

After manufacturing the adhesive film, a 5-inch solar cell having 57 finger electrodes (thickness 20 μm, width 0.1 mm) formed on the light receiving surface and two bus bar electrodes (width 2 mm) formed on the back surface ( 125 mm×125 mm thickness 200 μm) was prepared. Next, an adhesive film was attached to the finger electrodes on the light receiving surface and the bus bar electrodes on the back surface, and tab wires having a width of 1.5 mm were temporarily fixed. Then, using a thermocompression bonding machine for solar cells (HBS02608 manufactured by Shibaura Mechatronics Co., Ltd.), thermocompression bonding was performed at a temperature of 180° C., a pressure of 1.0 MPa, and a bonding time of 10 seconds to connect the solar cells and the tab wires. The solar cell module according to Example 1 was obtained.
[Example 2]

An adhesive film was prepared in the same manner as in Example 1. For thermocompression bonding of the tab wires, a soldering device (NTS-150-Ms, a simple tabbing device manufactured by NPC Co., Ltd.) improved for connecting the tab wires was used. In this device, the hot air supply nozzles arranged along the longitudinal direction of the tab wire are connected to the tip side by a pressing member having a width wider than the line width of the tab wire, while supplying hot air from the hot air supply nozzle. The pressure member applies pressure to the area where the tab wire is arranged. Using this apparatus, a solar cell module according to Example 2 was obtained under the conditions of a stage temperature of 170° C., a hot air temperature of 200° C., a pressure of 0.3 MPa, and a connection time of 3 seconds.
[Example 3]

The sun according to Example 3 was the same as Example 2 except that 30 parts by mass of conductive particles of solder (Mnitsui Mining & Smelting Co., Ltd. Sn96.5-Ag3.5 average particle size 10 μm) were used in the production of the adhesive film. A battery module was obtained.
[Example 4]

A solar cell module according to Example 4 was prepared in the same manner as in Example 2 except that 30 parts by mass of nickel conductive particles (Nippon Kagaku Kogyo Co., Ltd., Bright 25NR20-MX average particle size 20 μm) were used for producing the adhesive film. Obtained.
[Example 5]

A solar cell module according to Example 5 was obtained in the same manner as in Example 2 except that conductive particles were not used in the production of the adhesive film.
[Comparative Example 1]

An adhesive film was prepared in the same manner as in Example 1. After producing the adhesive film, 57 finger electrodes (width 0.1 mm) and 2 bus bar electrodes (width 2.0 mm) are formed on the light-receiving surface, and 2 bus bar electrodes (width 2 mm) are formed on the back surface. The prepared 5-inch solar cell (125 mm×125 mm, thickness 200 μm) was prepared. Then, the solar cell and the tab wire were connected in the same manner as in Example 2 to obtain a solar cell module according to Comparative Example 1.
[Comparative example 2]

A solar cell module according to Comparative Example 2 was obtained in the same manner as Comparative Example 1 except that conductive particles were not used in the production of the adhesive film.
[Comparative Example 3]

A solar cell module according to Comparative Example 3 was obtained in the same manner as Comparative Example 1 except that the pressure during thermocompression bonding by the thermocompression bonding machine for solar cells was set to 2.0 MPa.
[Effect confirmation test results]

FIG. 9: is a figure which shows the result of the effect confirmation test which concerns on an Example. Further, FIG. 10 is a diagram showing the results of the effect confirmation test according to the comparative example. As shown in FIG. 9, in each of Examples 1 to 5, it was confirmed that no cell cracking of the solar cell occurred and that the solar cell had excellent performance even in the initial connection. On the other hand, as shown in FIG. 10, in Comparative Examples 1 and 2, the thermocompression bonding was performed at a low pressure of 1.0 MPa or less, so that cell cracking of the solar cell did not occur, but the fill factor was low. It was confirmed that the initial connection performance was inferior to that of Examples 1 to 5. Further, in Comparative Example 3 in which thermocompression bonding was performed at a high pressure of 2.0 MPa, it was confirmed that cell cracking of the solar battery cell occurred.

DESCRIPTION OF SYMBOLS 1... Solar cell module, 2, 32, 42... Solar cell, 2a, 32a, 42a... Light receiving surface, 3... Tab wire, 12... Finger electrode, 15... Adhesive film, 21... Pressing member, 22, 26 ... hot air supply nozzle (hot air supply part), 33, 43 ... bus bar electrode, P ... tab wire arrangement region.

Claims (11)

A method for manufacturing a solar cell module, in which finger electrodes arranged on the light-receiving surface of a solar cell and tab wires are connected using an adhesive film,
The light receiving surface of the solar cell is not provided with a bus bar electrode connecting between the finger electrodes,
In the placement region of the tab line on the finger electrode, the tab line is placed via the adhesive film provided along the placement region,
Arrangement of the hot air supply nozzles on the tip side of a plurality of hot air supply nozzles that extend in the thickness direction of the solar battery cells and that supply hot air arranged at predetermined intervals along the longitudinal direction of the adhesive film. A flat plate-shaped pressing member having a width wider than the line width of the tab wire is arranged along the direction, and hot air is supplied toward the solar battery cells by the hot air supply nozzle. While heating the pressure member, a pressure of 1.0 MPa or less is applied to the arrangement region of the tab wire by the pressure member to thermocompress the tab wire ,
The hot air supply nozzle has a support member that projects from the hot air discharge port and supports the pressure member,
The method for manufacturing a solar cell module, wherein the support member is provided so as to sandwich at least the discharge port therebetween . A method for manufacturing a solar cell module, in which finger electrodes and tab wires arranged on the light receiving surface of a solar cell are connected using an adhesive film,
On the light receiving surface of the solar cell, a bus bar electrode connecting between the finger electrodes is provided with a width narrower than the width of the adhesive film,
In the area where the tab wire is arranged on the bus bar electrode, the tab wire is arranged via the adhesive film provided along the arrangement area,
Arrangement of the hot air supply nozzles on the tip side of a plurality of hot air supply nozzles that extend in the thickness direction of the solar battery cells and that supply hot air arranged at predetermined intervals along the longitudinal direction of the adhesive film. A flat plate-shaped pressing member having a width wider than the line width of the tab wire is arranged along the direction, and hot air is supplied toward the solar battery cells by the hot air supply nozzle. While heating the pressure member, a pressure of 1.0 MPa or less is applied to the arrangement region of the tab wire by the pressure member to thermocompress the tab wire ,
The hot air supply nozzle has a support member that projects from the hot air discharge port and supports the pressure member,
The method for manufacturing a solar cell module, wherein the support member is provided so as to sandwich at least the discharge port therebetween . A method for manufacturing a solar cell module, in which finger electrodes and tab wires arranged on the light receiving surface of a solar cell are connected using an adhesive film,
On the light receiving surface of the solar cell, a bus bar electrode connecting between the finger electrodes is provided only on the end side of the light receiving surface with a width narrower than the width of the adhesive film,
In the arrangement area of the tab wire on the finger electrode located on the center side of the light-receiving surface, the adhesive film provided along the arrangement area so that at least a part of the bus bar electrode overlaps, Place the tab line,
Arrangement of the hot air supply nozzles on the tip side of a plurality of hot air supply nozzles that extend in the thickness direction of the solar battery cells and that supply hot air arranged at predetermined intervals along the longitudinal direction of the adhesive film. A flat plate-shaped pressing member having a width wider than the line width of the tab wire is arranged along the direction, and hot air is supplied toward the solar battery cells by the hot air supply nozzle. While heating the pressure member, a pressure of 1.0 MPa or less is applied to the arrangement region of the tab wire by the pressure member to thermocompress the tab wire ,
The hot air supply nozzle has a support member that projects from the hot air discharge port and supports the pressure member,
The method for manufacturing a solar cell module, wherein the support member is provided so as to sandwich at least the discharge port therebetween . The method of manufacturing a solar cell module according to claim 1, wherein the tab wire is arranged so as to straddle all the finger electrodes on the light receiving surface. The method for manufacturing a solar cell module according to claim 1, wherein the finger electrodes have a thickness of 10 μm to 30 μm and a width of 5 μm to 90 μm. The method for manufacturing a solar cell module according to claim 1 or 3, wherein the ratio of the thickness of the finger electrodes to the thickness of the adhesive film is in the range of 1:5 to 6:5. The method of manufacturing a solar cell module according to claim 2, wherein the width of the bus bar electrode is 90 μm or less. The method of manufacturing a solar cell module according to claim 2, wherein the bus bar electrode has a thickness of 10 μm to 30 μm and a width of 5 μm to 90 μm. The method for manufacturing a solar cell module according to claim 1, wherein the tab wire is thermocompression bonded by applying a pressure of 0.5 MPa or less to an area where the tab wire is arranged. An insulating adhesive film is used as said adhesive film, The manufacturing method of the solar cell module as described in any one of Claims 1-9 characterized by the above-mentioned. The sun according to any one of claims 1 to 10, wherein the plurality of hot air supply nozzles supplies hot air from a direction normal to a main surface of the pressing member toward the main surface of the pressing member. Battery module manufacturing method.

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