TW201342641A - Solar cell, output measurement method and manufacturing method for solar cell, and manufacturing method for solar cell module - Google Patents

Abstract

To exactly measure output characteristics of a solar cell without necessity for use of a measurement fixture. The present invention comprises: a plurality of finger electrodes 12 mounted on a light-receiving surface in parallel to each other; an outer peripheral electrode 15 that is disposed along an outside edge of the light-receiving surface and connected with the plurality of finger electrodes 12; and pads 16 that is connected with the outer peripheral electrode 15 and connected with measurement instruments 19, 20 for measuring output characteristics.

Description

Solar cell unit, solar cell unit output measuring method, solar cell unit manufacturing method, and solar cell module manufacturing method

The present invention relates to a method for measuring the output characteristics of a solar cell, and a method for producing a solar cell, a method for producing a solar cell, and a method for manufacturing a solar cell, which are suitable for measuring an output characteristic of a solar cell.

The present application claims priority on the basis of Japanese Patent Application No. 2011-271410, filed on Dec.

Conventionally, a measurement jig for measuring the electrical output characteristics of a solar cell unit generally uses a measurement jig having a plurality of probes that are in contact with a bus bar electrode of the solar cell. This type of measurement jig includes a current measuring probe for measuring a current flowing through a solar cell, and a voltage measuring probe for measuring a voltage generated by the solar cell.

As shown in FIG. 12 and FIG. 13 , the measurement of the output characteristics of the solar cell is performed by a four-terminal method in which the current measuring probe 50 and the voltage measuring probe 51 are brought into contact with each other. The bus bar electrode 54 of the solar battery unit 53 measures the current flowing through the solar battery unit 53 and the voltage generated by the solar battery unit 53 while irradiating the light receiving surface of the solar battery unit 53 with approximately sunlight.

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2006-118983

However, in recent years, in order to reduce the number of manufacturing steps of solar cells, and to reduce the amount of use of electrode materials such as silver paste, and to reduce the cost of manufacturing, a method has been proposed in which a bus bar electrode is not provided and a conductive adhesive film is used. A tab line as an interconnector is directly connected in a manner to intersect with a finger electrode. In the solar cell unit having no busbar structure, the current collecting efficiency is equal to or higher than that of the solar cell in which the bus bar electrode is formed.

When the output characteristics of the solar cell unit 55 having such a busbarless structure are measured, the probe 56 must be brought into direct contact with the finger electrode 57. However, as shown in FIG. 14, the interval between the mounting intervals of the probes 56 and the formation of the finger electrodes 57 is often not uniform. In this case, all of the finger electrodes 57 cannot be turned on, and the measurement is not performed. The finger electrode 57 is not properly measured for output characteristics.

In order to solve such a problem, a measurement method has been proposed in which a rectangular plate-shaped rod electrode is used for measuring a terminal without using a probe, and is disposed on a light receiving surface of a solar cell unit so as to intersect with all of the finger electrodes.

However, in the measurement method using the rod electrode, it is necessary to uniformly contact the contact surfaces of the rod electrodes with the respective finger electrodes, but the flatness of the rod electrode abutting surface is formed with high precision, or the rod electrode is adjusted relative to the sun. The level of battery cells becomes more difficult. Further, when the height of the finger electrodes is not uniform in the plane of the solar cell, it is difficult to make the rod electrodes abut against all of the finger electrodes with sufficient pressure.

Therefore, in order to measure the output of the solar cell unit having no busbar structure, there are considerable problems in the countermeasures resulting from the improvement of the measuring jig, and the development thereof requires considerable cost and time. The present invention has been made in view of the problems, and an object of the present invention is to provide a solar battery unit and a solar battery unit that can accurately measure the output characteristics of a solar battery unit having no bus bar structure, not only for a solar battery unit having a bus bar electrode. Output measurement method.

In order to solve the above problems, the solar battery unit of the present invention includes a plurality of finger electrodes that are disposed in parallel with each other on the light receiving surface, and an outer peripheral electrode that is disposed along a side edge of the light receiving surface and that is connected to the plurality of finger electrodes. And a pad connected to the peripheral electrode and connected to a measuring device for measuring output characteristics.

Further, in the method for measuring the output of the solar battery cell of the present invention, the terminal connected to the measuring device for measuring the output characteristics of the solar battery cell is connected to the solar battery cell including the plurality of finger electrodes, the outer peripheral electrode and the pad. And measuring the output characteristics of the solar cell by irradiating a specific light to the light receiving surface; and the plurality of finger electrodes are disposed in parallel with each other on the light receiving surface; and the outer peripheral electrode is disposed along a side edge of the light receiving surface And connected to the plurality of finger electrodes; and a pad: connected to the outer peripheral electrode for measuring output characteristics.

Further, in the method for producing a solar cell of the present invention, by applying a conductive paste on a light receiving surface, a configuration is adopted in which a plurality of finger electrodes are provided in parallel with each other, and an outer peripheral electrode is provided on the outer side of the light receiving surface. The edge is connected to the plurality of finger electrodes; and the pad is connected to the outer peripheral electrode and connected to a measuring device for measuring an output characteristic of the solar cell.

Moreover, the manufacturing method of the solar cell module of the present invention is by coating conductivity Pasting on the light receiving surface to form a plurality of finger electrodes arranged in parallel with each other; the outer peripheral electrode is disposed along a side edge of the light receiving surface and connected to the plurality of finger electrodes; and a pad The outer peripheral electrode is connected to a measuring device that measures the output characteristics of the solar cell; and the lead wire is connected to the solar cell via an adhesive, whereby the solar cell is connected via the lead wire and is sealed via a sealing resin. The surface cover material and the rear sheet are laminated by a plurality of the above-mentioned solar battery cells connected by the above-mentioned leader sheets.

According to the present invention, the terminal connected to the measuring device is connected to the pad provided on the light receiving surface. Therefore, even in the solar battery cell having no bus bar structure, there is no problem such as measurement failure due to poor connection between the measurement jig and the finger electrode, and the measurement of the output characteristics can be accurately performed.

1‧‧‧Solar battery module

2‧‧‧Solar battery unit

3‧‧‧ lead line

4‧‧‧string

5‧‧‧Matrix

6‧‧‧Sheet

7‧‧‧Surface cover material

8‧‧‧Back sheet

9‧‧‧Metal frame

10‧‧‧ photoelectric conversion components

12‧‧‧ finger electrodes

13‧‧‧Back electrode

14‧‧‧ lead plate connection

15‧‧‧ peripheral electrode

16‧‧‧ pads

17‧‧‧ Conductive adhesive film

18‧‧‧Binder resin

19‧‧‧ galvanometer

20‧‧‧ voltmeter

21‧‧‧Wire

23‧‧‧ Bus bar electrode

24‧‧‧Electrical particles

25‧‧‧ peeling film

26‧‧‧ reel

50, 51‧‧‧ probe

53‧‧‧Solar battery unit

54‧‧‧ bus bar electrode

55‧‧‧Solar battery unit

56‧‧‧ probe

57‧‧‧ finger electrode

Fig. 1 is an exploded perspective view showing the configuration of a solar battery module to which the present invention is applied.

Figure 2 is a cross-sectional view showing a string of solar cells.

Figure 3 is a top plan view of a solar cell unit.

Figure 4 is a bottom view of the solar cell unit.

Fig. 5 is a plan view showing a main part of a mat provided on the outer edge of the solar cell.

Figure 6 is a plan view of a solar cell unit.

Figure 7 is a plan view of a solar cell unit.

Fig. 8 is a cross-sectional view showing a conductive adhesive film.

Fig. 9 is a cross-sectional view showing a conductive adhesive film which is attached to a release substrate and wound into a cylindrical shape.

Fig. 10 is a schematic plan view showing measurement of electrical output characteristics of a solar cell.

Fig. 11 is a schematic cross-sectional view showing measurement of electrical output characteristics of a solar cell.

Fig. 12 is a perspective view showing a state in which measurement of electrical characteristics of a solar cell is performed by a measuring device of a probe used previously.

Fig. 13 is a view showing the measurement performed by the measuring device of the previously used probe.

Fig. 14 is a view for explaining measurement of electrical characteristics of a solar battery cell having a busbar-free structure using a measuring device of a previously used probe.

Hereinafter, a solar battery cell to which the present invention is applied, a method for measuring an output of a solar battery cell, a method for manufacturing a solar battery cell, and a method for manufacturing a solar battery module will be described in detail with reference to the drawings. It is a matter of course that the present invention is not limited to the embodiments described below, and various modifications can be made without departing from the spirit and scope of the invention, and the drawings are schematic, and the ratios of the respective dimensions may be different from actual ones. The specific dimensions and the like should be judged by referring to the following description. Moreover, it is of course also included in the portions in which the dimensional relationships or ratios of the drawings differ from each other.

[solar battery module]

As shown in FIG. 1 to FIG. 4, the solar battery module 1 to which the present invention is applied has a string 4 in which a plurality of solar battery cells 2 are connected in series by using a lead wire 3 as an interconnect, and is provided with A matrix 5 in which a plurality of the strings 4 are arranged. Further, the matrix 5 is sandwiched by the sheet 6 for sealing the adhesive, and the surface cover material 7 provided on the light-receiving surface side and the back surface sheet 8 provided on the back surface side are laminated together, and finally aluminum is mounted around the surface. The metal frame 9 is thereby formed into the solar cell module 1.

As the sealing adhesive, for example, an ethylene-vinyl alcohol polymer resin (EVA, Translucent sealing material such as ethylene-vinyl alcohol resin. Further, as the surface cover member 7, a light transmissive material such as glass or translucent plastic can be used. Further, as the back sheet 8, a laminate in which a glass or an aluminum foil is sandwiched by a resin film can be used.

[solar battery unit]

Each of the solar battery cells 2 of the solar battery module 1 has a photoelectric conversion element 10. Hereinafter, a crystal ray-based solar cell using a single crystal germanium photoelectric conversion element or a polycrystalline germanium photoelectric conversion element as the photoelectric conversion element 10 will be described as an example. However, the present invention can use a thin film germanium solar cell, an organic system, a quantum dot type, or the like. Various photoelectric conversion elements.

As shown in FIG. 3, the solar cell unit 2 is provided with a finger electrode 12 on the light-receiving surface side, and the finger electrode 12 is a surface electrode for collecting electricity generated inside. The finger electrodes 12 are formed on the two sides facing the surface of the light receiving surface of the solar cell 2, and are coated with a conductive paste such as Ag paste by screen printing or the like, followed by firing. Further, the finger electrodes 12 are formed over the entire surface of the light receiving surface, and a plurality of lines having a width of, for example, about 50 to 200 μm are formed at predetermined intervals, for example, 2 mm and substantially parallel.

[peripheral electrode 15 / pad 16]

Further, the solar cell 2 is provided on the surface of the light receiving surface and is provided with the outer peripheral electrode 15 along the outer edge of the cell. The outer peripheral electrode 15 is connected to the plurality of finger electrodes 12 juxtaposed on the light receiving surface side, and is also connected to the pad 16 described below, whereby the finger electrodes 12 are coupled to the pads 16. The outer peripheral electrode 15 surrounds the outer edge of the light receiving surface of the solar cell 2, and is connected to each end of the plurality of finger electrodes 12 formed between the opposite sides.

The outer peripheral electrode 15 is formed by, for example, applying an Ag paste by screen printing or the like, and is formed by firing, and is formed simultaneously with the finger electrode 12.

The outer peripheral electrode 15 is connected to a pad 16 as a measurement terminal for measuring the output characteristics of the solar battery cell 2. The solar cell unit 2 can measure the output characteristics by connecting the pads 16 to the terminals of the wires 21 to which the ammeter 19 or the voltmeter 20 is connected.

The pad 16 is adjacent to the outer peripheral electrode 15 and is formed in a plurality of light receiving surfaces of the solar cell unit 2, for example, in a side edge other than the light receiving surface of the solar cell unit 2, and is formed on two side edges perpendicular to the longitudinal direction of the finger electrode 12. It is adjacent to and adjacent to the outer peripheral electrode 15. Each of the pads 16 is formed, for example, in a rectangular shape, and is formed by, for example, an Ag paste by screen printing or the like, and is formed by firing, and is formed simultaneously with the finger electrodes 12 or the outer peripheral electrodes 15.

A plurality of pads 16 are formed in the solar cell unit 2, whereby at least one of them is a current measuring terminal, and the other is a voltage measuring terminal. In other words, in the measurement of the output characteristics, the solar cell 2 does not use the measuring jig having the probe that abuts the finger electrode or the bus bar electrode, but the wire 21 connected to the galvanometer 19 and the voltmeter 20 is connected. The pad 16 is attached to measure the output characteristics.

The pad 16 is preferably formed to have a side width W of more than 1 mm and an area of 4 mm ² or more. At this time, as shown in FIG. 5, the distance from the outer side edge of the solar battery cell 2 toward the inner surface side is set to the width W of the pad 16, and the distance parallel to the outer side edge of the solar cell unit 2 is set to length. When the pad 16 has a width of 1 mm or less or an area of less than 4 mm ² , the connection area between the terminals of the wires 21 for measuring current or voltage is insufficient and the connection is poor. Here, the solar cell unit 2 can be provided with the solar cell unit 2 as a device for accurately measuring current or voltage by forming a substantially rectangular pad 16 and making the width W of one side larger than 1 mm to an area of 4 mm ² or more. Good shape of the connection terminals.

Further, if the area of the pad 16 on the light-receiving surface of the solar cell 2 is too large, the conversion efficiency due to the shadow loss is lowered. Therefore, it is preferable to form, for example, 10 mm ² or less.

Further, the pad 16 may be provided in any one of the light receiving surfaces of the solar battery cells 2 as long as it is adjacent to the outer peripheral electrode 15, and may be provided on the two sides perpendicular to the longitudinal direction of the finger electrodes 12 as shown in FIG. In addition to this, for example, one side edge or two side edges of the finger electrode 12 in the longitudinal direction, or a corner portion of the solar cell unit 2 may be provided, for example.

[Bus/No Bus]

Since the solar battery cells 2 are slightly perpendicular to the respective finger electrodes 12, they are busbar electrodes which are not provided with electricity for collecting the electrodes of the finger electrodes 12, that is, have no bus bar structure. Therefore, the following lead wire 3 of the solar battery cell 2 is directly connected to the finger electrode 12 via the conductive adhesive film 17.

Further, as shown in FIG. 7, the solar battery unit 2 may also use a solar battery unit in which the bus bar electrodes 23 are formed. In this case, in order to increase the light-receiving area and improve the conversion efficiency, the solar battery cell 2 preferably has the bus bar electrode 23 thinned, for example, to have a width of 1.0 mm or less. In addition, when the bus bar electrode 23 is formed to have a width of 1.0 mm or less, it is difficult to accurately connect the probe with the conventional measurement jig, and there is a measurement variation or the like. However, as described above, the solar cell unit 2 is provided. Since the pad 16 for outputting the measurement terminal is used, the measurement of the output characteristics can be accurately performed even when the ultra-fine bus bar electrode 23 is used.

[back electrode 13]

Further, the photoelectric conversion element 10 is provided with a back surface electrode 13 made of aluminum or silver on the back side opposite to the light receiving surface. As shown in FIGS. 2 and 4, the back surface electrode 13 is formed of an electrode made of aluminum or silver by, for example, screen printing or sputtering, which is equal to the back surface of the solar cell unit 2. Back The surface electrode 13 has a tab wire connecting portion 14 that is connected to the tab wire 3 via the conductive adhesive film 17 described below.

Further, as shown in FIG. 2, the solar cell unit 2 electrically connects the finger electrodes 12 formed on the surface and the back electrode 13 of the adjacent solar cell unit 2 by the tab line 3, thereby forming a series connection. String 4. The tab wire 3 and the finger electrode 12 and the back surface electrode 13 are connected by the following conductive adhesive film 17.

[leading board 3]

As shown in FIG. 2, the tab line 3 is formed of an elongated conductive substrate that electrically connects the cells of the adjacent solar cell units 2a, 2b, and 2c, for example, a thickness of 50 to 300 μm is used. The strip-shaped copper foil having substantially the same width as the conductive adhesive film 17 is subjected to gold plating, silver plating, tin plating, tin-plated lead or the like as necessary. Further, as the conductive adhesive film, a tab wire which is laminated on the lead wire and which is provided with a conductive adhesive film may be used.

[Electrically conductive film 17]

As shown in FIG. 8 , the conductive adhesive film 17 is made of a thermosetting adhesive resin 18 and contains conductive particles 24 at a high density, and is formed into a film shape. For example, SP100 series can be used by Sony Chemicals & Information Co., Ltd. .

The conductive particles 24 used for the conductive adhesive film 17 are not particularly limited, and examples thereof include gold plating of metal particles such as nickel, gold, silver, and copper, and resin particles. The outermost layer is made of an insulating cover or the like.

The composition of the adhesive resin 18 of the conductive adhesive film 17 is not particularly limited, and it is more preferable to use, for example, a thermosetting epoxy-based curable resin composition or an acrylic curable resin composition.

The epoxy-based thermosetting resin composition is composed of, for example, a compound having two or more epoxy groups in the molecule, or a resin, an epoxy curing agent, a film-forming component, or the like.

a compound or a resin having two or more epoxy groups in the molecule, which may be in the form of a liquid or a solid, and examples thereof include a difunctional epoxy resin such as a bisphenol A epoxy resin or a bisphenol F epoxy resin. A novolac type epoxy resin such as a phenol novolac type epoxy resin or a cresol novolac type epoxy resin. Further, 3,4-epoxycyclohexnylmethyl-3', 4'-epoxycyclohexane carboxylate or the like can be used. An alicyclic epoxy compound.

Examples of the epoxy curing agent include an amine curing agent, an imidazole curing agent, an acid anhydride curing agent, and a phosphonium cation curing agent. The hardener can also be latent.

The film-forming component may, for example, be a phenoxy resin or an acrylic resin which is compatible with an epoxy compound or an epoxy resin.

The epoxy-based thermosetting resin composition may optionally contain a known stress-relieving agent such as a curing accelerator, a decane coupling agent, a metal scavenger or a butadiene rubber, an inorganic filler such as cerium oxide, or a polyisocyanate crosslinking. Agents, coloring materials, preservatives, solvents, and the like.

The acrylic thermosetting resin composition is composed of, for example, a (meth) acrylate monomer, a film-forming resin, an inorganic filler such as cerium oxide, a decane coupling agent, a radical polymerization initiator, or the like.

As the (meth) acrylate monomer, a monofunctional (meth) acrylate monomer, a polyfunctional (meth) acrylate monomer, or an epoxy group or an urethane group may be introduced therein. Modified monofunctional or polyfunctional (meth) propyl group, amine group, oxirane group, propylene oxide group, etc. Oxate monomer. Further, as long as the effects of the present invention are not impaired, other monomers capable of radically copolymerizing with the (meth) acrylate monomer, such as (meth)acrylic acid, vinyl acetate, styrene, vinyl chloride or the like, may be used in combination.

Examples of the film-forming resin for the acrylic thermosetting resin composition include a phenoxy resin, a polyvinyl acetal resin, a polyvinyl butyral resin, an alkylated cellulose resin, and a polyester resin. Acrylic resin, styrene resin, amine ester resin, polyethylene terephthalate resin, and the like.

The radical polymerization initiator may, for example, be an organic peroxide such as benzamidine peroxide, dicumyl peroxide or dibutyl peroxide, or an azodiamine such as azobisisobutyronitrile or azobisvaleronitrile. Compound.

The acrylic thermosetting resin composition may contain a stress relieving agent such as butadiene rubber or a solvent such as ethyl acetate, a coloring matter, an antioxidant, an anti-aging agent, or the like, as needed.

A well-known method can be used for forming the self-adhesive resin 18 into the conductive adhesive film, and the adhesive resin 18 is an epoxy-based thermosetting resin composition containing the conductive particles 24 or an acrylic thermosetting resin composition. Composition. For example, the conductive particles 24, the film-forming resin, the liquid epoxy resin, the latent curing agent, and the decane coupling agent are dissolved in a solvent, and the resulting solution for forming a resin is applied onto the release sheet 25 to form a solvent. Volatilization is performed to obtain a conductive adhesive film 17 formed into a film shape. As the solvent, toluene, ethyl acetate or the like can be used, or a mixed solvent of these can be used.

The release sheet 25 is not particularly limited, and PET (poly ethylene terephthalate), OPP (oriented polypropylene), PMP (poly-4-methlpentene-1), PTFE (polytetrafluoroethylene), or the like can be used. As shown in FIG. 9, the film-shaped conductive adhesive film 17 is It is wound into a cylindrical shape.

[Method of Manufacturing Solar Cell Module]

The conductive adhesive film 17 supported by the release sheet 25 is pulled out from the reel 26 in actual use, and cut into a specific length substantially the same as one side of the solar cell unit 2, and then the release sheet 25 is peeled off to The electrode 12 is attached to the light receiving surface in a substantially vertical manner, and is attached to the tab line connecting portion 14 of the back surface electrode 13. At this time, the conductive adhesive film 17 is thermally pressed by the temperature, pressure, and time at which the adhesive resin 18 exhibits a degree of fluidity which is not thermally cured. Further, when the bus bar electrode 23 is formed on the light receiving surface of the solar battery cell 2, the conductive adhesive film 17 is attached to the bus bar electrode 23.

Thereafter, the conductive adhesive film 17 is disposed to overlap the lead wire 3, and is hot-pressed by a heating adapter, thereby flowing out from the lead wire 3 and the finger electrode 12 or the tab wire connecting portion 14, and via conductive The particles are in direct contact with each other, and the binder resin 18 is thermally cured in this state. Thereby, the conductive adhesive film 17 can achieve connection between the tab line 3 and the finger electrodes 12 and the back surface electrodes 13.

Further, by this, a solar battery string 4 in which a plurality of solar battery cells 2 are connected by a tab line 3 is formed. The matrix 5 in which the strings 4 are arranged in plural is a sheet 6 having a light-transmitting sealing adhesive such as EVA for sealing the solar battery cells 2 on the front and back surface layers, and the surface cover member 7 provided on the light-receiving surface side and The back sheet 8 on the back side is laminated together, and finally the metal frame 9 of aluminum or the like is attached to the periphery to complete the solar cell module 1.

In the above, a conductive adhesive film having a film shape has been described, but there is no problem even if it is a paste. Further, as the solar battery cell 2, an insulating adhesive film not containing the conductive particles 24 or an insulating paste may be used. In this case, the finger electrode 12 and the back electrode 13 and the guide line The adhesive resin 18 is thermally cured in a state of being directly connected.

In addition, the conductive adhesive film 17 and the insulating adhesive film may have a laminate in which the lead wires 3 are pre-bonded by roll lamination or the like in advance on the surface opposite to the surface on which the release sheet 25 is provided. By using such a laminate, the connection between the conductive adhesive film 17 and the insulating adhesive film and the tab line 3 can be simultaneously performed in one hot pressing step.

[Method for measuring output characteristics]

The measurement of the output characteristics of the solar cell unit 2 is performed before the steps of forming the finger electrode 12, the outer peripheral electrode 15 and the pad 16 on the light receiving surface, and forming the back surface electrode 13 on the back surface and before attaching the conductive adhesive film 17 or the like. .

As described above, the measurement of the output characteristics of the solar battery unit 2 is performed without using a dedicated measuring jig, and the wire 21 is connected between the pad 16 and the back surface electrode 13 provided on the light receiving surface side, and the wire is connected. The galvanometer 19 and the voltmeter 20 are connected to the 21 series. Therefore, in the solar battery cell 2 having no busbar structure, there is no problem such as measurement failure due to poor connection between the measurement jig and the finger electrode 12, and the measurement of the output characteristics can be accurately performed.

For example, when two pads 16 are formed on each of the opposite sides of the solar cell 2, as shown in FIG. 10, one pair of pads is used for current measurement, and the other pair is used for voltage measurement, respectively, by wires 21 After the connection, as shown in FIGS. 11(a) and (b), the back electrode 13 is connected via an ammeter 19 or a voltmeter 20.

Further, at this time, the solar battery cell 2 can have a substantially rectangular pad 16 and have a width W of more than 1 mm and an area of 4 mm ² or more, and can have a necessary shape as a connection terminal for measuring current and voltage. The connection to the wire 21 is prevented from being poor.

Moreover, since the solar battery unit 2 uses the pad 16 to measure the output characteristics, For example, when the ultrafine bus bar electrode 23 having a width of 1 mm or less is provided, there is no problem that the contact between the probe of the measuring jig and the bus bar electrode 23 is poor due to the narrowing of the width of the bus bar electrode 23. Further, since it is not necessary to make the bus bar electrode 23 thick, the shielding loss can be reduced.

[Examples]

Next, an embodiment in which the output characteristics of the solar battery cells 2 are measured will be described. In the solar battery cells 2 of the examples and the comparative examples, a crystal honeycomb cell having a shape of 5 inches was used, and the conversion efficiency (%) of the solar cell 2 was determined by the methods of the examples and the comparative examples. The measurement was carried out using a solar simulator (manufactured by Nisshinbo Mechatronics, solar simulator PVS1116i-M) and under standard measurement conditions (illuminance 1000 W/m ² , temperature 25 ° C, spectrum AM 1.5 G). In addition, the measurement was performed by the so-called four-terminal method, and it measured based on JIS C8913 (crystal-system solar cell output measurement method).

Then, the ratio of the measured value to the theoretical output value of the solar cell (measured value / theoretical output value of the solar cell) is calculated. The theoretical output value of the solar cell unit refers to the theoretical output value of the solar cell unit of the examples and the comparative examples. When the performance of the solar cell unit is 100%, the measured value (the theoretical output value of the solar cell) is 1. In the present embodiment, as a criterion for judging the goodness and the poorness of the measurement of the output characteristics, the (measured value/the theoretical output value of the solar cell) is 0.99 or more, and the value is not set to 0.99.

Embodiment 1 uses a solar cell unit 2 constructed without a bus bar electrode. In the solar battery cell 2 of the first embodiment, two pads 16 are formed in the vicinity of the two side edges perpendicular to the longitudinal direction of the finger electrodes 12 on the side edges of the light receiving surface. Each of the pads 16 was formed into a 2 mm × 2 mm square by coating an Ag paste and calcined, and the pad area was 4 mm ² .

The solar cell unit 2 of the second embodiment is connected to the longitudinal direction of the finger electrode 12. The same conditions as in the first embodiment were carried out except that one pad 16 was formed in the vicinity of the two side edges of the vertical direction.

The solar battery cell 2 of the third embodiment has the same conditions as those of the first embodiment except that the size of the mat 16 is 2 mm × 3 mm and the pad area is 6 mm ² .

The solar battery cell 2 of the fourth embodiment has the same conditions as those of the first embodiment except that the size of the mat 16 is 3 mm × 3 mm square and the pad area is 9 mm ² .

The solar battery cell 2 of the fifth embodiment has the same conditions as those of the first embodiment except that the size of the mat 16 is 4 mm × 2 mm and the pad area is 8 mm ² .

In the solar battery cell 2 of the sixth embodiment, the size of the mat 16 was a rectangle of 5 mm × 2 mm, and the pad area was 10 mm ² . Otherwise, the same conditions as in the first embodiment were employed.

In the solar battery cell 2 of the seventh embodiment, the solar cell unit 2 having a bus bar electrode having a width of 1.0 mm was used, and the same conditions as in the first embodiment were employed.

In Comparative Example 1, the solar cell unit having no bus bar electrode structure was used, and the solar cell unit in which the pad 16 was not formed was used, and the probe was measured by abutting the probe of the measurement jig having the conventional probe. .

In Comparative Example 2, the shape of the mat 16 was a rectangle having a width of 1 mm × a length of 1 mm, and the pad area was 1 mm ² , and the same conditions as in Example 1 were employed.

In Comparative Example 3, the shape of the mat 16 was a rectangle having a width of 1 mm × a length of 2 mm, and the pad area was 2 mm ² , and the same conditions as in Example 1 were employed.

In Comparative Example 4, the shape of the mat 16 was a rectangle having a width of 1 mm × a length of 4 mm, and the pad area was 4 mm ² , and the same conditions as in Example 1 were employed.

The measurement results are shown in Table 1. As shown in Table 1, it is understood that any of Examples 1 to 7 (measured value/the theoretical output value of the solar cell) is 0.99, and the output result is substantially the same as the theoretical output value, and can be used without any problem.

On the other hand, in Comparative Example 1, since the contact between the finger electrode and the probe was poor, the output was seriously lower than the theoretical output value.

Further, in Comparative Example 2 and Comparative Example 3, since the pad area was narrow, and the width W of the pad in Comparative Example 2 to Comparative Example 4 was 1 mm narrow, any one of them would be in poor contact with the wire. This results in a significantly lower output than the theoretical output.

2‧‧‧Solar battery unit

12‧‧‧ finger electrodes

15‧‧‧ peripheral electrode

16‧‧‧ pads

Claims (16)

A solar cell unit comprising a plurality of finger electrodes, a peripheral electrode and a pad: a plurality of finger electrodes arranged in parallel with each other on a light receiving surface; and a peripheral electrode disposed along a side edge of the light receiving surface and having the plurality of The finger electrodes are connected; and a pad is connected to the peripheral electrode and connected to a measuring device for measuring output characteristics. The solar battery unit according to claim 1, wherein the light-receiving surface is formed with a bus bar electrode, and the bus bar electrode is connected to the plurality of finger electrodes, and a lead wire connecting the solar cells is connected. The solar battery unit according to claim 2, wherein the bus bar electrode has a width of 1 mm or less. In the solar cell unit of claim 1, the busbar electrode is not disposed on the light receiving surface. The solar battery unit according to any one of claims 1 to 4, wherein the mats are respectively disposed in the vicinity of the outer edges of the opposite sides of the solar battery cells. The solar cell unit of claim 5, wherein the pad has a width of 2 to 5 mm. The solar cell unit of claim 6, wherein the pad has an area of 4 to 10 mm ² . A method for measuring an output of a solar battery unit, wherein a terminal connected to a measuring device that measures an output characteristic of the solar battery cell is connected to the pad of a solar battery unit including a plurality of finger electrodes, an outer peripheral electrode, and a pad, and is irradiated Measuring the output characteristics of the solar cell by using a specific light to the light receiving surface; and the plurality of finger electrodes are disposed in parallel with each other on the light receiving surface; and the outer peripheral electrode is disposed along a side edge of the light receiving surface and is plural Finger electrode connection; The pad is connected to the outer peripheral electrode and used to measure output characteristics. The method for measuring the output of a solar cell according to claim 8 , wherein a bus bar electrode is formed on the light receiving surface, and the bus bar electrode is connected to the plurality of finger electrodes and connected to the solar cell. Guide board line. The method for measuring the output of a solar battery cell according to claim 9, wherein the bus bar electrode has a width of 1 mm or less. The method for measuring the output of a solar battery unit according to claim 8 is characterized in that the busbar electrode is not provided on the light receiving surface. The method for measuring the output of a solar battery cell according to any one of claims 8 to 11, wherein the mat is provided in the vicinity of the outer edge of the opposite sides of the solar cell. The method for measuring the output of a solar cell according to claim 12, wherein the pad has a width of 2 to 5 mm. The solar cell unit of claim 13, wherein the pad has an area of 4 to 10 mm ² . A method for manufacturing a solar cell is characterized in that a conductive paste is applied onto a light-receiving surface to form a plurality of finger electrodes which are disposed in parallel with each other; and an outer peripheral electrode is provided along a side edge of the light-receiving surface and The pad is connected to the plurality of finger electrodes; the pad is connected to the outer peripheral electrode and connected to a measuring device for measuring the output characteristics of the solar cell. A solar cell module manufacturing method is characterized in that a solar cell unit having a plurality of finger electrodes, a peripheral electrode and a pad is formed by applying a conductive paste on a light receiving surface: the plurality of finger electrodes are parallel to each other Setting; the above peripheral electrode is along the above a light receiving surface is disposed at a side edge of the light receiving surface and connected to the plurality of finger electrodes; and the pad is connected to the outer peripheral electrode and connected to a measuring device for measuring an output characteristic of the solar battery unit; and the lead wire is connected to the solar battery via an adhesive. The unit is connected to the solar cell unit via the lead wire, and the plurality of solar cell units connected by the lead wire are laminated on the surface cover material and the rear surface via a sealing resin.