Solar cell module manufacturing method and solar cell module

First, first cell wiring members from the first solar cell and second cell wiring members from the second solar cell are sandwiched between a wiring member film and a second bridge wiring member. Subsequently, the first cell wiring members and the second cell wiring members are connected to the second bridge wiring member by applying heat to at least the first cell wiring members, the second cell wiring members, and the second bridge wiring member by induction heating.

CROSS-REFERENCE OF RELATED APPLICATIONS

This application is the U.S. National Phase under 35 U.S.C. § 371 of International Patent Application No. PCT/JP2019/033006, filed on Aug. 23, 2019, which in turn claims the benefit of Japanese Patent Application No. 2018-185513, filed on Sep. 28, 2018, the entire disclosures of which Applications are incorporated by reference herein.

TECHNICAL FIELD

The present invention relates to manufacturing technology and, more particularly, to a method of manufacturing a solar cell module including a plurality of solar cells and to a solar cell module.

BACKGROUND ART

A solar cell module includes a plurality of solar cells. A solar cell is available as a cell of a standard size (156 mm×156 mm) and a half-cut cell of a size (156 mm×78 mm) half the standard size. When a half-cut cell is used, a plurality of solar cells are grouped into, for example, two sections, and three solar cell strings are included in each section. Further, the two sections are connected in parallel by being connected to a bridge wiring member at the central portion (see, for example, non patent literature 1).[Non Patent Literature 1][online], Internet<http://www.js-ge.cn/product.asp?Product_ID=321&classid=69>

SUMMARY OF INVENTION

Technical Problem

A wire film configured by connecting two transparent members by a plurality of wires may be used to simplify the manufacturing of a solar cell module. In the case a wire film is used in a solar cell module, the two transparent members are adhesively attached to adjacent solar cells respectively, and the wires are used as wiring members. There are cases in which the transparent member is pasted to the bridge wiring member by heating the transparent member in order to connect the plurality of wires extending from the solar cell provided at the end of a solar cell string to the bridge wiring member. If the transparent member is heated, however, the transparent member is damaged by the heat, and improper connection results.

The disclosure addresses the above-described issue, and a general purpose thereof is to provide a technology of ensuring proper connection between a solar cell and a bridge wiring member.

Solution to Problem

A method of manufacturing a solar cell module according to an embodiment of the present disclosure is adapted for a solar cell module including: a bridge wiring member that extends in a first direction; a first solar cell string that extends, of a first region and a second region separated and interfaced by the bridge wiring member, in the first region and in a second direction different from the first direction; and a second solar cell string that extends in the second region and in the second direction. The first solar cell string includes a first solar cell provided on a side of the bridge wiring member. The second solar cell string includes a second solar cell provided on a side of the bridge wiring member and facing the first solar cell, sandwiching the bridge wiring member, the method comprising: attaching a plurality of first cell wiring members to the first solar cell by means of a first cell film; attaching a plurality of second cell wiring members to the second solar cell by means of a second cell film; sandwiching the plurality of first cell wiring members from the first solar cell and the plurality of second cell wiring members from the second solar cell between a wiring member film and the bridge wiring member; and connecting the plurality of first cell wiring members and the plurality of second cell wiring members to the bridge wiring member by applying heat to at least the plurality of first cell wiring members, the plurality of second cell wiring members, and the bridge wiring member by induction heating.

Another embodiment of the present disclosure relates to a solar cell module. The solar cell module includes: a bridge wiring member that extends in a first direction; a first solar cell string that extends, of a first region and a second region separated and interfaced by the bridge wiring member, in the first region and in a second direction different from the first direction; and a second solar cell string that extends in the second region and in the second direction. The bridge wiring member includes a first surface having a length in the first direction and a width in the second direction and a second surface opposite to the first surface. The first solar cell string includes a first solar cell provided on a side of the bridge wiring member. The second solar cell string includes a second solar cell provided on a side of the bridge wiring member and facing the first solar cell, sandwiching the bridge wiring member. The plurality of first cell wiring members extending from the first solar cell toward the bridge wiring member are connected to the first surface of the bridge wiring member, and the plurality of second cell wiring members extending from the second solar cell toward the bridge wiring member are connected to the second surface of the bridge wiring member.

Advantageous Effects of Invention

According to this disclosure, it is ensured that the solar cell and the bridge wiring member are connected properly.

DESCRIPTION OF EMBODIMENTS

A brief summary will be given before describing the disclosure in specific details. Embodiment 1 relates to a solar cell module in which a plurality of solar cells are arranged in a matrix. An encapsulant is provided between the first protection member and the second protection member in the solar cell module. The encapsulant encapsulates a plurality of solar cell. In this process, the two adjacent solar cells are connected by a wire film. As described above, a wire film is configured as two transparent members connected by a plurality of wires, and the respective transparent members are adhesively attached to adjacent solar cells. Since the wire plays the role of a wiring member, a solar cell string is formed by connecting a plurality of solar cells arranged in a direction of extension of the wire by means of a plurality of wire films. A wire film like this is used to simplify the manufacturing of a solar cell module.

Meanwhile, a half-cut cell may be used as a solar cell, and a bridge wiring member may be provided at the central portion. In this configuration, a solar cell string is provided in each of two regions separated and interfaced by the bridge wiring member (hereinafter, the two separated regions will be referred to as “first region” and “second region”, respectively), and the end of each solar cell string is connected to the bridge wiring member. To describe it more specifically, the solar cell provided at the end of the solar cell string in the first region and the solar cell provided at the end of the solar cell string in the second region face each other, sandwiching the bridge wiring member, and a plurality of wires from the respective solar cells are connected to the bridge wiring member. In such a connection, a transparent member is adhesively attached to the bridge wiring member, sandwiching the wires, in order to reinforce connection between the wires and the bridge wiring member. If heat is applied for adhesive attachment, the transparent member is damaged by the heat, and improper connection results. Also, if the transparent member is damaged by the heat, the appearance of the solar cell module will be deteriorated due to the damaged transparent member. Therefore, suppression of damage to the transparent member caused during adhesive attachment is called for.

In this embodiment, the bridge wiring member, the wires, and the transparent member are stacked in the stated order, and the transparent member is heated from above by using induction heating. Induction heating applies heat only to a metal portion and connects the bridge wiring member and the wires such that damage to the transparent member is suppressed. The terms “parallel” and “perpendicular” in the following description not only encompass completely parallel or perpendicular but also encompass off-parallel and off-perpendicular within the margin of error. The term “substantially” means identical within certain limits.

FIG.1is a plan view showing the structure of a solar cell module100. As shown inFIG.1, a rectangular coordinate system formed by an x axis, y axis, and z axis is defined. The x axis and y axis are orthogonal to each other in the plane of the solar cell module100. The z axis is perpendicular to the x axis and y axis and extends in the direction of thickness of the solar cell module100. The positive directions of the x axis, y axis, and z axis are defined in the directions of arrows inFIG.1, and the negative directions are defined in the directions opposite to those of the arrows. Of the two principal surfaces forming the solar cell module100that are parallel to the x-y plane, the principal surface disposed on the positive direction side along the z axis is the light receiving surface, and the principal surface disposed on the negative direction side along the z axis is the back surface. Hereinafter, the positive direction side along the z axis will be referred to as “light receiving surface side” and the negative direction side along the z axis will be referred to as “back surface side”. When the x axis direction is referred to as the “first direction”, the y axis direction is referred to as the “second direction”. Therefore,FIG.1can be said to be a plan view of the solar cell module100as viewed from the light receiving surface side.

The solar cell module100includes a 1-1st solar cell10aa, . . . , a 1-24th solar cell10ax, a 2-1st solar cell10ba, . . . , a 2-24th solar cell10bx, which are generically referred to as solar cells10, a first bridge wiring member14a, . . . , a tenth bridge wiring member14j, which are generically referred to as bridge wiring members14, a first frame20a, a second frame20b, a third frame20c, and a fourth frame20d, which are generically referred to as frames20.

The first frame20aextends in the x axis direction, and the second frame20bextends in the negative direction along the y axis from the positive direction end of the first frame20aalong the x axis. Further, the third frame20cextends in the negative direction along the x axis from the negative direction end of the second frame20balong the y axis, and the fourth frame20dconnects the negative direction end of the third frame20calong the x axis and the negative direction end of the first frame20aalong the x axis. The frames20bound the outer circumference of the solar cell module100and are made of a metal such as aluminum. The first frame20aand the third frame20care longer than the second frame20band the fourth frame20d, respectively, so that the solar cell module100has a rectangular shape longer in the x axis direction than in the y axis direction.

The first bridge wiring member14athrough the tenth bridge wiring member14jextend in the x axis direction. The first bridge wiring member14athrough the fourth bridge wiring member14dare provided on a line in the central portion of the solar cell module100salong the y axis. A first region90ais provided on the positive direction side along the y axis and a second region90bis provided on the negative direction side along the y axis across a boundary defined by the first bridge wiring member14athrough the fourth bridge wiring member14d. The first region90aand the second region90beach has a rectangular shape more elongated in the x axis direction than in the y axis direction. The fifth bridge wiring member14ethrough the seventh bridge wiring member14gare arranged on a line in the first region90atoward the positive direction end of the solar cell module100along the y axis. Further, the eighth bridge wiring member14hthrough the tenth bridge wiring member14jare arranged on a line in the second region90btoward the negative direction end of the solar cell module100along the y axis.

Each of the plurality of solar cells10absorbs incident light and generates photovoltaic power. In particular, the solar cell10generates an electromotive force from the light absorbed on the light receiving surface and also generates photovoltaic power from the light absorbed on the back surface. The solar cell10is formed by, for example, a semiconductor material such as crystalline silicon, gallium arsenide (GaAs), or indium phosphorus (InP). The structure of the solar cell10is not limited to any particular type. It is assumed that crystalline silicon and amorphous silicon are stacked by way of example. The solar cell10is a half-cut cell described above and has a rectangular shape more elongated in the x axis direction than in the y axis direction, but the shape of the solar cell10is not limited to this. A plurality of finger electrodes extending in the x axis direction in a mutually parallel manner are disposed on the light receiving surface and the back surface of each solar cell10.

The plurality of solar cells10are arranged in a matrix on the x-y plane. In this case, four solar cells10are arranged in the y axis direction in the first region90a. The finger electrode on the light receiving surface side of one of the two solar cells10adjacent to each other in the y axis direction and the finger electrode on the back surface side of the other solar cell are electrically connected by a cell wiring member (not shown).FIG.2is a cross sectional view showing the structure of the solar cell module100.FIG.2is a cross-sectional view along the y axis and is an A-A′ cross-sectional view ofFIG.1. The solar cell module100includes a 1-6th solar cell10af, a 1-7th solar cell10ag, cell wiring members16, a first protection member30, a first encapsulant32, a second encapsulant34, a second protection member36, a light receiving surface side cell film40, a back surface side cell film42, a light receiving surface side adhesive44, and a back surface side adhesive46. The top ofFIG.2corresponds to the light receiving surface side, and the bottom corresponds to the back surface side.

The first protection member30is disposed on the light receiving surface side of the solar cell module100and protects the surface of the solar cell module100. Further, the solar cell module100is shaped in a rectangle bounded by the frames20on the x-y plane. The first protection member30is formed by using a translucent and water shielding glass, translucent plastic, etc. The first protection member30increases the mechanical strength of the solar cell module100.

The first encapsulant32is stacked on the back surface side of the first protection member30. The first encapsulant32is disposed between the first protection member30and the solar cell10and adhesively attaches the first protection member30and the solar cell10. For example, a thermoplastic resin film of polyolefin, ethylene-vinyl acetate copolymer (EVA), polyvinyl butyral (PVB), polyimide, or the like may be used as the first encapsulant32. A thermosetting resin may alternatively be used. The first encapsulant32is formed by a translucent sheet member having a surface of substantially the same dimension as the x-y plane in the first protection member30.

The 1-6th solar cell10afand the 1-7th solar cell10agare stacked on the back surface side of the first protection member30. The solar cells10are provided such that the light receiving surface22faces the positive direction side along the z axis and the back surface24faces the negative direction side along the z axis. When the light receiving surface22is referred to as the “first surface”, the back surface24is referred to as the “second surface”. The cell wiring members16, the light receiving surface side adhesive44, and the light receiving surface side cell film40are provided on the light receiving surface22of the solar cell10, and the cell wiring members16, the back surface side adhesive46, and the back surface side cell film42are provided on the back surface24of the solar cell10.FIG.3will be used to describe the above arrangement in the solar cell10.

FIG.3is a perspective view showing the structure of a film80used in the solar cell module100. The film80includes the cell wiring members16, the light receiving surface side cell film40, the back surface side cell film42, the light receiving surface side adhesive44, and the back surface side adhesive46. The film80corresponds to the wire film described above, the light receiving surface side cell film40and the back surface side cell film42correspond to the transparent member described above, and the cell wiring members16correspond to the wires described above. The cell wiring members16each has a diameter of 100-500 μm, and, preferably, 300 μm, which is thinner than the width 1-2 mm of a tab wire commonly used in a solar cell module. Meanwhile, the number of cell wiring members16is 10-20, which is larger than the number of tab wires commonly used in a solar cell module. For example, the cell wiring members16extend in a cylindrical shape, and the side surface of the cylinder is coated by a solder.

The light receiving surface side cell film40is provided on the light receiving surface22side of one of the two adjacent solar cells10, and, for example, the 1-6th solar cell10af. The light receiving surface side cell film40is formed by a transparent resin film of, for example, polyethylene terephthalate (PET). The light receiving surface side cell film40has a rectangular shape smaller than the solar cell10on the x-y plane. The light receiving surface side adhesive44is provided on the surface of the light receiving surface side cell film40toward the 1-6th solar cell10af, and the plurality of cell wiring members16are provided in the light receiving surface side adhesive44. By attaching the light receiving surface side adhesive44on the light receiving surface22of the 1-6 solar cell10af, the cell wiring members16are sandwiched between the light receiving surface side cell film40and the 1-6th solar cell10af. For example, EVA is used for the light receiving surface side adhesive44.

The back surface side cell film42is provided on the back surface24side of the other of the two adjacent solar cells10, and, for example, the 1-7th solar cell10ag. Like the light receiving surface side cell film40, the back surface side cell film42is formed by a transparent resin film of, for example, PET. The back surface side cell film42has a rectangular shape smaller than the solar cell10on the x-y plane. The back surface side adhesive46is provided on the surface of the back surface side cell film42toward the 1-7th solar cell10ag, and the plurality of cell wiring members16are provided in the back surface side adhesive46. By attaching the back surface side adhesive46on the back surface24of the 1-7 solar cell10ag, the cell wiring members16are sandwiched between the back surface side cell film42and the 1-7th solar cell10ag. For example, EVA is used for the back surface side adhesive46.

The film80configured as described above and the solar cell module100are manufactured separately. In manufacturing the solar cell module100, the light receiving surface side adhesive44is provided on the light receiving surface22of the 1-6th solar cell10af, and the back surface side adhesive46is provided on the back surface24of the 1-7th solar cell10ag, as described above. By providing the adhesives in this way, the cell wiring members16electrically connects the finger electrode (not shown) on the light receiving surface22of the 1-6th solar cell10afand the finger electrode (not shown) on the back surface24of the 1-7th solar cell10ag. Reference is mad back toFIG.2.

The light receiving surface side cell film40and the back surface side cell film42are equally provided in the other solar cells10. The second encapsulant34is stacked on the back surface side of the first encapsulant32. The second encapsulant34encapsulates the plurality of solar cells10, the cell wiring members16, the bridge wiring members14, the light receiving surface side cell film40, the back surface side cell film42, etc., sandwiching them between the first encapsulant32and the second encapsulant34. The same member as used for the first encapsulant32may be used for the second encapsulant34. Alternatively, the second encapsulant34may be integrated with the first encapsulant32by heating the members in a laminate cure process.

The second protection member36is stacked on the back surface side of the second encapsulant34so as to face the first protection member30. The second protection member36protects the back surface side of the solar cell module100as a back sheet. A resin film of, for example, PET, polytetrafluoroethylene (PTFE), etc., a stack film having a structure in which an Al foil is sandwiched by resin films of polyolefin, or the like is used as the second protection member36. Reference is made back toFIG.1.

As described above, the 1-1st solar cell10aathrough the 1-4th solar cell10adarranged in the y axis direction are connected in series by the cell wiring members16, and the 1-5th solar cell10aethrough the 1-8th solar cell10ahare also connected in series by the cell wiring members16. Further, the 1-4th solar cell cell10adand the 1-5th solar cell10aeare connected to the fifth bridge wiring member14e. As a result, electrical connection between the 1-1st solar cell10aathrough the 1-4th solar cell10ad, the fifth bridge wiring member14e, and the 1-5th solar cell10aethrough the 1-8th solar cell10ahforms the 1-1st solar cell string12aa.

In the first region90a, the 1-2nd solar cell string12aband the 1-3rd solar cell string12acare similarly formed, and the 1-1st solar cell string12aathrough the 1-3 solar cell string12acare arranged on a line in the x axis direction. In the second region90b, the 2-1st solar cell string12bathrough the 2-3 solar cell string12bcare similarly arranged on a line in the x axis direction. For example, the 2-1st solar cell string12abis formed by electrical connection between the 2-1st solar cell10bathrough the 2-4th solar cell10bd, the eighth bridge wiring member14h, and the 2-5th solar cell10bethrough the 2-8th solar cell10bh. The number of solar cells10included in one solar cell string12is not limited to “8”, and the number of solar cell strings12is not limited to “6”. In other words, the solar cell module100need not have a rectangular shape more elongated in the x axis direction than in the y axis direction and may have a rectangular shape less elongated in the x axis direction than in the y axis direction depending on the number of solar cells10included in one solar cell string12or the number of solar cell strings12. Alternatively, the solar cell module100may have a rectangular shape having the same length in the y axis direction and in the x axis direction.

The first bridge wiring member14athrough the fourth bridge wiring member14delectrically connect the solar cell strings12in the first region90aand the solar cell strings12in the second region90b. For example, the first bridge wiring member14aconnect the 1-1st solar cell10aaof the 1-1st solar cell string12aaand the 2-1st solar cell string10baof the 2-1st solar cell string12ba. Further, the second bridge wiring member14bconnects the 1-8th solar cell10ahof the 1-1st solar cell string12aaand the 1-9th solar cell10aiof the 1-2nd solar cell string12abin the first region90a. Still further, the second bridge wiring member14bconnects the 2-8th solar cell10bhof the 2-1st solar cell string12baand the 2-9th solar cell10biof the 2-2nd solar cell string12bbin the second region90b.

The 1-8th solar cell10ahand the 1-9th solar cell10aiare respectively provided on the side of the 1-1st solar cell string12aaand the 1-2 solar cell string12abtoward the second bridge wiring member14b, Further, 2-8th solar cell10bhand the 2-9th solar cell10biare respectively provided on the side of the 2-1st solar cell string12baand the 2-2 solar cell string12bbtoward the second bridge wiring member14b, Still further, the 1-8th solar cell10ahand the 2-8th solar cell10bhface each other, sandwiching the second bridge wiring member14b, and the 1-9th solar cell10aiand the 2-9th solar cell10bialso face each other, sandwiching the second bridge wiring member14b. Similar connections are established in the third bridge wiring member14cand the fourth bridge wiring member14d.

This connects the 1-1st solar cell string12aa, the 1-2nd solar cell string12ab, and the 1-3rd solar string12acin series. The connection may be referred to as “fist section”. The 2-1st solar cell string12ba, the 2-2nd solar cell string12bb, and the 2-3rd solar string12bcare also connected in series. The connection may be referred to as “second section”. Further, the first section and the second section are connected in parallel. A lead wiring member (not shown) is connected to the first bridge wiring member14aand the fourth bridge wiring member14d. The lead wiring member is a wiring member for retrieving the electric power generated in the plurality of solar cells10outside the solar cell module100.

FIG.4is an enlarged plan view showing the structure of a portion of the solar cell module100. The figure shows a portion of the 1-8th solar cell10ah, the 1-9th solar cell10ai, the 2-8th solar cell10bh, the 2-9th solar cell10bi, and the second bridge wiring member14bofFIG.1. A rectangular surface50having a length in the x axis direction and a width in the y axis direction is provided on the light receiving surface side of the second bridge wiring member14b.

The light receiving surface side cell film40attached to the 1-8th solar cell10ahis referred to as a first cell film60a, and the cell wiring members16provided in the first cell film60aare referred to as first cell wiring members16a. Therefore, the plurality of first cell wiring members16aare connected to the 1-8th solar cell10ahby the first cell film60aand extend from the 1-8th solar cell10ahtoward the second bridge wiring member14b. Further, the light receiving surface side cell film40attached to the 2-8th solar cell10bhis referred to as a second cell film60b, and the cell wiring members16provided in the second cell film60bare referred to as the second cell wiring members16b. Therefore, the plurality of second cell wiring members16bare connected to the 2-8th solar cell10bhby the second cell film60band extend from the 2-8th solar cell10bhtoward the second bridge wiring member14b.

Each of the plurality of first cell wiring members16aextends on the surface50of the second bridge wiring member14btoward the end facing the 2-8th solar cell10bh. Each of the plurality of second cell wiring members16bextends on the surface50of the second bridge wiring member14btoward the end facing the 1-8th solar cell10ah. Each of the plurality of first cell wiring member16aand each of the plurality of second cell wiring members16bare arranged on the surface50such that they are displaced from each other in the x axis direction and mutually overlap in the y axis direction. In other words, the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare in mesh with each other in a comb tooth pattern on the surface50of the second bridge wiring member14b.

Further, a wiring member film62is provided on the surface50of the second bridge wiring member14bso as to cover the plurality of first cell wiring members16aand the plurality of second cell wiring members16b. The wiring member film62will be described later. In other words, the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare provided between the surface50of the second bridge wiring member14band the wiring member film62. It can be said that the plurality of first cell wiring member16aand the plurality of second cell wiring members16bare connected to the second bridge wiring member14bby the wiring member film62.

The back surface side cell film42(not shown) is adhesively attached to the back surface side of the 1-9th solar cell10ai, and the cell wiring members16are sandwiched between the 1-9th solar cell10aiand the back surface side cell film42. The back surface side cell film42adhesively attached to the 1-9th solar cell10aiis also referred to as the first cell film60a, and the cell wiring members16provided in the first cell film60aare also referred to as the first cell wiring members16a. Therefore, the plurality of first cell wiring members16aare connected to the 1-9th solar cell10aiby the first cell film60aand extend from the 1-9th solar cell10aitoward the second bridge wiring member14b.

The back surface side cell film42(not shown) is also adhesively attached to the back surface side of the 2-9th solar cell10bi, and the cell wiring members16are sandwiched between the 2-9th solar cell10biand the back surface side cell film42. The back surface side cell film42adhesively attached to the 2-9th solar cell10biis also referred to as the second cell film60b, and the cell wiring members16provided in the second cell film60bare also referred to as the second cell wiring members16b. Therefore, the plurality of second cell wiring members16bare connected to the 2-9th solar cell10biby the second cell film60band extend from the 2-9th solar cell10bitoward the second bridge wiring member14b.

Each of the plurality of first cell wiring members16aextends from the back surface side to the light receiving surface side and extends on the surface50of the second bridge wiring member14btoward the end facing the 2-9th solar cell10bi. Each of the plurality of second cell wiring members16bextends from the back surface side to the light receiving surface side and extends on the surface50of the second bridge wiring member14btoward the end facing the 1-9th solar cell10ai. The arrangement of the plurality of first cell wiring members16aand the plurality of second cell wiring members16bon the surface50and the arrangement of the wiring member film62on the surface of the second bridge wiring member14bare as described above, and a description thereof is omitted. Connection like this between the cell wiring members16and the bridge wiring member14is equally established in the bridge wiring members14other than the second bridge wiring member14b.

A description will now be given of a method of manufacturing the solar cell module100.

(1) The film80shown inFIG.3is prepared to connect two adjacent solar cells10. The solar cell string12is produced by layering the light receiving surface side cell film40of the film80on one of the two adjacent solar cells10and layering the back surface side cell film42of the film80on the other of the two adjacent solar cells10.

(2) The film80is prepared to connect the solar cell10provided at the end of the solar cell string12to the bridge wiring member14.FIGS.5A-5Bare plan views showing the structure of the film80used in the solar cell module100.FIG.5Ashows a first film80athat should be adhesively attached to the 1-8th solar cell10ahofFIG.4and a second film80bthat should be adhesively attached to the 2-8th solar cell10bh. The first cell film60ais provided toward the first end of the plurality of first cell wiring members16ain the first film80a, and the first wiring member film62ais provided toward the second end opposite to the first end. The first wiring member film62ahas a size different from that of the light receiving surface side cell film40but is configured in a manner similar to the light receiving surface side cell film40. The light receiving surface side adhesive44and the plurality of first cell wiring members16aare provided on the back surface side of the first cell film60a, and an adhesive (not shown) and the plurality of first cell wiring members16aare provided on the back surface side of the first wiring member film62a.

The second cell film60bis provided toward the first end of the plurality of second cell wiring members16bin the second film80b, and the second wiring member film62bis provided toward the second end opposite to the first end. The second wiring member film62bis configured in a manner similar to the first wiring member film62a. The light receiving surface side adhesive44and the plurality of second cell wiring members16bare provided on the back surface side of the second cell film60b, and an adhesive (not shown) and the plurality of second cell wiring members16bare provided on the back surface side of the second wiring member film62b. One of the first wiring member film62aand the second wiring member film62bis removed. It is assumed here that the first wiring member film62ais maintained. The first wiring member film62amaintained corresponds to the wiring member film62ofFIG.4.

FIG.5Bshows the first film80athat should be adhesively attached to the 1-9th solar cell10aiofFIG.4and the second film80bthat should be adhesively attached to the 2-9th solar cell10bi. The first cell film60ais provided toward the first end of the plurality of first cell wiring members16ain the first film80a, and the first wiring member film62ais provided toward the second end opposite to the first end. The back surface side adhesive46and the plurality of first cell wiring members16aare provided on the light receiving surface side of the first cell film60a, and an adhesive (not shown) and the plurality of first cell wiring members16aare provided on the back surface side of the first wiring member film62a.

The second cell film60bis provided toward the first end of the plurality of second cell wiring members16bin the second film80b, and the second wiring member film62bis provided toward the second end opposite to the first end. The back surface side adhesive46and the plurality of second cell wiring members16bare provided on the light receiving surface side of the second cell film60b, and an adhesive (not shown) and the plurality of second cell wiring members16bare provided on the back surface side of the second wiring member film62b. One of the first wiring member film62aand the second wiring member film62bis removed. It is also assumed here that the first wiring member film62ais maintained. The first wiring member film62amaintained corresponds to the wiring member film62ofFIG.4.

(3) By attaching the light receiving surface side adhesive44of the first cell film60aofFIG.5Ato the light receiving surface22of the 1-8th solar cell10ah, the first cell film60ais attached to the 1-8th solar cell10ah. By attaching the light receiving surface side adhesive44of the second cell film60bto the light receiving surface22of the 2-8th solar cell10bh, the second cell film60bis attached to the 2-8th solar cell10bh. By attaching the back surface side adhesive46of the first cell film60aofFIG.5Bto the back surface24of the 1-8th solar cell10ah, the first cell film60ais attached to the 1-8th solar cell10ah. By attaching the back surface side adhesive46of the second cell film60bto the back surface24of the 2-8th solar cell10bh, the second cell film60bis attached to the 2-8th solar cell10bh. A similar process is performed for the other solar cells10. (2) and (3) may be reversed in the sequence.

(4) The second end of each of the plurality of second cell wiring members16bofFIG.5Ais placed on the surface50of the second bridge wiring member14b. In this state, the second end of each of the plurality of first cell wiring members16ais placed on the surface50of the second bridge wiring member14bsuch that the second end of each of the plurality of first cell wiring members16aand the second end of each of the plurality of second cell wiring members16bare displaced in the x axis direction and mutually overlap in the y axis direction. As a result, the wiring member film62covering the plurality of first cell wiring members16ais provided on the surface50of the second bridge wiring member14bsuch that the wiring member film62also covers the plurality of second cell wiring members16b. In other words, the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare sandwiched between the surface50of the second bridge wiring member14band one wiring member film62. A similar process is performed for the other bridge wiring members14.

(5) The portion in which the wiring member film62, the plurality of first cell wiring members16a, the plurality of second cell wiring members16b, and the second bridge wiring member14bare layered (hereinafter, referred to as “joint portion”) is heated by induction heating.FIG.6is a cross sectional view showing the structure a manufacturing apparatus200for manufacturing a solar cell module. The manufacturing apparatus200includes a lower apparatus70, an upper apparatus72, and a coil74. The lower apparatus70is a table to place the joint portion, and the joint portion is placed on the lower apparatus70with the back surface side facing down. The joint portion represents a portion in the B-B′ cross section ofFIG.4. The upper apparatus72is placed on the light receiving surface side of the joint portion. The upper apparatus72is used to fix the wiring member film62, the plurality of first cell wiring members16a, the plurality of second cell wiring members16b, and the second bridge wiring member14brelative to each other in the joint portion. The upper apparatus72is a weight having a weight not so heavy as to disrupt the joint portion. In this state, the coil74is arranged to encircle the upper apparatus72.

When an AC current is induced in the coil74, lines of magnetic force with a varying orientation and intensity is generated around the coil74. When the joint portion is placed near the lines of magnetic force, the substance in the joint portion that conducts electricity (e.g., metal) is affected by the varying lines of magnetic force to induce an eddy current in the metal. When an eddy current flows in the metal, Joule heat is generated due to the electrical resistance of the metal, causing the metal to generate heat. Induction heating applies heat directly to the plurality of first cell wiring members16a, the plurality of second cell wiring members16b, and the second bridge wiring member14bbut does not apply heat directly to the wiring member film62. As a result, the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare connected to the surface50of the second bridge wiring member14b.

(6) A stack is produced by layering the first protection member30, the first encapsulant32, the solar cell string12, the second encapsulant34, and the second protection member36in the stated order in the positive-to-negative direction along the z axis.

(7) A laminate cure process performed for the stack. In this process, air is drawn from the stack, and the stack is heated and pressurized so as to be integrated. In vacuum lamination in the laminate cure process, the temperature is set to about 100-170°.

According to this embodiment, the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare sandwiched between the wiring member film62and the bridge wiring member14and heat is applied by induction heating. It is therefore ensured that the wiring member film62is not directly heated. Further, since the wiring member film62is not directly heated, damaged to the wiring member film62is suppressed. Further, since damage to the wiring member film62is suppressed, the solar cell10and the bridge wiring member14are connected properly. Further, since damage to the wiring member film62is suppressed, the appearance of the solar cell module100is inhibited from being deteriorated. Further, since the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare connected by the wiring member film62to the bridge wiring member14, adhesion by the solder around the cell wiring members16and the wiring member film62is realized. Further, since adhesion by the solder around the cell wiring members16and the wiring member film62is realized, the strength of connection is increased. Further, since the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare connected by the wiring member film62to the bridge wiring member14, the manufacturing steps are simplified.

Further, the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare connected to the surface50of the bridge wiring member14such that the first cell wiring members16aand the second cell wiring members16boverlap along the second direction. Therefore, the area of contact between the cell wiring members16and the bridge wiring member14is increased when the solar cell10is connected to the bridge wiring member14. Further, since the area of contact between the cell wiring members16and the bridge wiring member14is increased, the electrical resistance is inhibited from increasing. Further, since the electrical resistance is inhibited from increasing, the electrical property of the solar cell module100is improved. Further, since the area of contact between the cell wiring members16and the bridge wiring member14is increased, the strength of connection is inhibited from being reduced. Further, since the strength of connection is inhibited from being reduced, the reliability of the portion of connection is improved. Further, since a wire thinner than a tab wire is used for the cell wiring members16, the impact on the appearance of the solar cell module100of a displacement in the position of the cell wiring members16in the solar cell string12in the first region90aand the solar cell string12in the second region90bis reduced.

Further, since the plurality of first cell wiring members16aare connected to the first solar cell10by the first cell film60aand the plurality of second cell wiring members16bare connected to the second solar cell10by the second cell film60b, the manufacturing steps are simplified. Further, since the plurality of first cell wiring members16aextend on the surface50of the bridge wiring member14as far as the end facing the second solar cell10and the plurality of second cell wiring members16bextend on the surface of the bridge wiring member14as far as the end facing the first solar cell10, the area of contact is increased.

One embodiment of the disclosure is summarized below. A method of manufacturing a solar cell module100according to an embodiment of the present disclosure is adapted for a solar cell module100including: a bridge wiring member14that extends in a first direction; a first solar cell string12that extends, of a first region90aand a second region90bseparated and interfaced by the bridge wiring member14, in the first region90aand in a second direction different from the first direction; and a second solar cell string12that extends in the second region90band in the second direction. The first solar cell string12includes a first solar cell10provided on a side of the bridge wiring member14. The second solar cell string12includes a second solar cell10provided on a side of the bridge wiring member14and facing the first solar cell10, sandwiching the bridge wiring member14, the method including: attaching a plurality of first cell wiring members16ato the first solar cell10by means of a first cell film60a; attaching a plurality of second cell wiring members16bto the second solar cell10by means of a second cell film60b; sandwiching the plurality of first cell wiring members16afrom the first solar cell10and the plurality of second cell wiring members16bfrom the second solar cell10between a wiring member film62and the bridge wiring member14; and connecting the plurality of first cell wiring members16aand the plurality of second cell wiring members16bto the bridge wiring member14by applying heat to at least the plurality of first cell wiring members16a, the plurality of second cell wiring members16b, and the bridge wiring member14by induction heating.

The bridge wiring member14may include a surface50having a length in the first direction and a width in the second direction. The sandwiching may include sandwiching the plurality of first cell wiring members16aand the plurality of second cell wiring members16bbetween one wiring member film62and the surface50of the bridge wiring member14.

The sandwiching may cause the plurality of first cell wiring members16aand the plurality of second cell wiring members16bto mutually overlap in the second direction.

A description will now be given of embodiment 2. Like embodiment 1, embodiment 2 relates to a solar cell module in which a plurality of solar cells are arranged in a matrix, and the joint portion is connected by induction heating. In embodiment 1, the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare provided on the surface50of the bridge wiring member14. In embodiment 2, one of the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare provided on the surface50on the light receiving surface side of the bridge wiring member14(hereinafter, “first surface”). Further, the other of the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare provided on the surface50on the back surface side of the bridge wiring member14(hereinafter, “second surface”). The solar cell module100according to embodiment 2 is of the same type as that ofFIG.1andFIG.2, and the film80is of the same type as shown inFIG.3. The following description concerns a difference from the foregoing embodiments.

FIG.7is an enlarged plan view showing the structure of a portion of the solar cell module100. The appearance is similar to that ofFIG.4. The second bridge wiring member14bhas a first surface50aon the light receiving surface side, and the first surface50acorresponds to the surface50discussed so far. The plurality of first cell wiring members16afrom the 1-8th solar cell10ahextend toward the second bridge wiring member14band extend on the first surface50aof the second bridge wiring member14bas far as the end facing the 2-8th solar cell10bh. Further, the first wiring member film62ais provided on the first surface50aof the second bridge wiring member14bso as to cover the plurality of first cell wiring members16a. The first wiring member film62ais shown inFIG.5A. In other words, the plurality of first cell wiring member16aare provided between the first surface50aof the second bridge wiring member14band the first wiring member film62a. It can be said that the plurality of first cell wiring member16aare connected to the second bridge wiring member14bby the first wiring member film62a.

The second bridge wiring member14bhas a second surface50bon the back surface side opposite to the light receiving surface side. Further, the back surface side cell film42adhesively attached to the back surface24of the 2-8th solar cell10bhis referred to as a second cell film60b. The plurality of second cell wiring members16bare provided between the back surface24of the 2-8th solar cell10bhand the second cell film60b. The plurality of second cell wiring members16bextend toward the second bridge wiring member14band extend on the second surface50bof the second bridge wiring member14bas far as the end facing the 1-8th solar cell10ah. Further, the second wiring member film62bis provided on the second surface50bof the second bridge wiring member14bso as to cover the plurality of second cell wiring members16b. The adhesive and the plurality of second cell wiring members16bare provided on the light receiving surface side of the second wiring member film62b. In this way, the plurality of first cell wiring members16aand the plurality of second cell wiring members16bare connected to different surfaces50of the second bridge wiring member14b.

The arrangement of the first cell wiring members16abetween the 1-9th solar cell10ai(not shown) and the second bridge wiring member14bis similar to the arrangement of the second cell wiring members16bbetween the 2-8th solar cell10bhand the second bridge wiring member14b. The arrangement of the second cell wiring members16bbetween the 2-9th solar cell10bi(not shown) and the second bridge wiring member14bis similar to the arrangement of the first cell wiring members16abetween the 1-8th solar cell10ahand the second bridge wiring member14b. Connection like this between the cell wiring members16, the bridge wiring member14, and the wiring member film62is equally established in the bridge wiring members14other than the second bridge wiring member14b.

A description will now be given of a method of manufacturing the solar cell module100. A description of those steps that are identical to the steps of embodiment 1 will be omitted.

(2) The film80is prepared to connect the solar cell10provided at the end of the solar cell string12to the bridge wiring member14. The configuration of the film80is as described above. The first wiring member film62aand the second wiring member film62bare both maintained.

(4) The second end of each of the plurality of first cell wiring members16afrom the 1-8th solar cell10ahis placed on the first surface50aof the second bridge wiring member14b. In this state, the first wiring member film62acovering the plurality of first cell wiring members16ais provided on the first surface50aof the second bridge wiring member14b. In other words, the plurality of first cell wiring members16aare sandwiched between the first surface50aof the second bridge wiring member14band the first wiring member film62a. The second end of each of the plurality of second cell wiring members16bfrom the 2-8th solar cell10bhis placed on the second surface50bof the second bridge wiring member14b. In this state, the second wiring member film62battached to the plurality of second cell wiring members16bis provided on the second surface50bof the second bridge wiring member14b. In other words, the plurality of second cell wiring members16bare sandwiched between the second surface50bof the second bridge wiring member14band second wiring member film62b. A similar process is performed for the other bridge wiring members14.

(5) The portion in which the first wiring member film62a, the plurality of first cell wiring members16a, the second bridge wiring member14b,sthe plurality of second cell wiring members16b, and the second wiring member film62bare layered (hereinafter, referred to as “joint portion”) is heated by induction heating.FIG.8is a cross sectional view showing the structure a manufacturing apparatus200for manufacturing the solar cell module100. The manufacturing apparatus200has the same configuration as that of embodiment 1. The joint portion represents a portion in the C-C′ cross section ofFIG.7. The first wiring member film62a, the plurality of first cell wiring members16a, the second bridge wiring member14b, the plurality of second cell wiring members16b, the second wiring member film62bare layered in the stated order in a direction from the upper apparatus72toward the lower apparatus70.

When an AC current is induced in the coil74, Induction heating applies heat directly to the plurality of first cell wiring members16a, the plurality of second cell wiring members16b, and the second bridge wiring member14bbut does not apply heat directly to the first wiring member film62aand the second wiring member film62b. As a result, the plurality of first cell wiring members16aare connected to the first surface50aof the second bridge wiring member14b, and plurality of second cell wiring members16bare connected to the second surface50bof the second bridge wiring member14b.

According to this embodiment, the plurality of first cell wiring members16aare sandwiched between the first wiring member film62aand the first surface50a, and the plurality of second cell wiring members16bare sandwiched between the second wiring member film62band the second surface50b. Accordingly, the two types of cell wiring members16are provided on different surfaces of the bridge wiring member14. Further, since the two types of cell wiring members16are provided on different surfaces of the bridge wiring member14, the manufacturing steps are simplified. Further, since the plurality of first cell wiring members16aare connected to the first surface50aof the bridge wiring member14and the plurality of second cell wiring members16bare connected to the second surface50bof the bridge wiring member14, the manufacturing steps are simplified.

One embodiment of the disclosure is summarized below. The bridge wiring member14may include a first surface50ahaving a length in the first direction and a width in the second direction and a second surface50bopposite to the first surface. The sandwiching includes sandwiching the plurality of first cell wiring members16abetween the first wiring member film62aand the first surface50aof the bridge wiring member14and sandwiching plurality of second cell wiring members16bbetween the second wiring member film62band the second surface59bof the bridge wiring member14.

Another embodiment of the present disclosure relates to a solar cell module100. The solar cell module100includes: a bridge wiring member14that extends in a first direction; a first solar cell string12that extends, of a first region90aand a second region90bseparated and interfaced by the bridge wiring member14, in the first region90aand in a second direction different from the first direction; and a second solar cell string12that extends in the second region90band in the second direction. The bridge wiring member14includes a first surface50ahaving a length in the first direction and a width in the second direction and a second surface50bopposite to the first surface50a. The first solar cell string12includes a first solar cell10provided on a side of the bridge wiring member14. The second solar cell string12includes a second solar cell10provided on a side of the bridge wiring member14and facing the first solar cell10, sandwiching the bridge wiring member14. The plurality of first cell wiring members16aextending from the first solar cell10toward the bridge wiring member14are connected to the first surface50aof the bridge wiring member14, and the plurality of second cell wiring members16bextending from the second solar cell10toward the bridge wiring member14are connected to the second surface50bof the bridge wiring member14.

Described above is an explanation of the present disclosure based on an exemplary embodiment. The embodiment is intended to be illustrative only and it will be understood by those skilled in the art that various modifications to constituting elements and processes could be developed and that such modifications are also within the scope of the present invention.

In embodiment 1, the plurality of first cell wiring members16afrom the 1-8th solar cell10ahextend on the surface50of the second bridge wiring member14bas far as the end facing the 2-8th solar cell10bh. Further, the plurality of second cell wiring members16bfrom the 2-8th solar cell10bhextend on the surface50of the second bridge wiring member14bas far as the end facing the 1-8th solar cell10ah. However, the configuration is not limited to this, and each of the first cell wiring members16amay extend on the surface50of the second bridge wiring member14bas far as a point between the end facing the 1-8th solar cell10ahand the end facing the 2-8th solar cell10bh. Further, the second cell wiring members16bmay extend on the surface50of the second bridge wiring member14bas far as a point between the end facing the 1-8th solar cell10ahand the end facing the 2-8th solar cell10bh. The same is true of the other cell wiring members16. According to this variation, the flexibility in configuration can be improved.

In embodiment 1, one of the first wiring member film62aand the second wiring member film62bis removed. Alternatively, however, a portion of the first wiring member film62amay be removed, and a portion of the second wiring member film62bmay be removed. The portion of the first wiring member film62athat remains and the portion of the second wiring member film62bthat remains are combined on the surface50of the bridge wiring member14to from the wiring member film62ofFIG.4. According to this variation, the flexibility in configuration can be improved.

INDUSTRIAL APPLICABILITY

According to this disclosure, it is ensured that the solar cell and the bridge wiring member are connected properly.

REFERENCE SIGNS LIST