JP4024161B2 - Manufacturing method of solar cell module - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a solar cell module and a manufacturing method thereof, and more particularly, a solar cell module including a plurality of solar cells electrically connected in series by a lead electrode made of a conductive member such as a metal foil or a metal wire, and a manufacturing method thereof. About.
[0002]
[Prior art]
Conventionally, in order to obtain a predetermined photovoltaic power from a solar cell, a solar cell module including a plurality of solar cells electrically connected in series by lead electrodes is known (see, for example, Patent Documents 1 and 2). .
[0003]
[Patent Document 1]
JP-A-11-214733
[Patent Document 2]
Japanese Patent Laid-Open No. 08-330615
[0004]
FIG. 11 is a cross-sectional view for explaining the structure of a conventional solar cell module in which a plurality of solar cells are electrically connected in series. FIG. 12 is a top view for explaining the top surface of solar cells electrically connected in series in the conventional solar cell module. With reference to FIG. 11 and FIG. 12, the structure of such a conventional solar cell module will be described below.
[0005]
As shown in FIGS. 11 and 12, the solar cells 101, 111, 121,... Are p-type polycrystalline Si wafers 101p, 111p, 121p each having n-type regions 101n, 111n, 121n,. It is composed of ... Moreover, on the upper surface of the solar cells 101, 111, 121,..., The first collector electrodes 102, 112, 121,... Formed using silver paste are on the lower surface of the solar cells 101, 111, 121,. Similarly, second collector electrodes 103, 113, 123,... Formed using silver paste are respectively formed.
[0006]
The first collector electrodes 102, 112, 122,... Are a pair of striped first collector electrode bus bar portions 102 a, 112 a, 122 a,. , 114, 124,..., And indicated by dotted lines), and a number of comb-like thin wire electrodes extending in a direction substantially orthogonal to the first collector electrode bus bar portions 102 a, 112 a, 122 a,. It has the 1st collector electrode finger part 102b, 112b, 122b, ... arrange | positioned. In addition, each of the second collector electrodes 103, 113, 123,... Is a pair of striped second collector electrode bus bar portions arranged in parallel to each other, like the first collector electrodes 102, 112, 122,. And a second collector electrode finger portion in which a number of comb-like fine wire electrodes extending in a direction substantially orthogonal to the second collector electrode bus bar portion are arranged.
[0007]
A pair of striped first lead electrodes 104, 114, 124,... Made of copper foil and arranged in parallel to each other are formed on the upper surfaces of the first collector electrode bus bar portions 102a, 112a, 122a,. Has been. Further, on the lower surface of the second collector electrode bus bar portion of the second collector electrodes 103, 113, 123,..., A pair of striped second lead electrodes 105 made of copper foil and arranged in parallel to each other, 115, 125,... Are respectively formed. The second lead electrodes 105, 115, 125,... Are formed only on the lower surface of the second collector electrode bus bar portion.
[0008]
The first lead electrodes 104, 114, 124,... Are arranged so as to extend from the upper surface and end portions of the solar cells 101, 111, 121,. In the electrically connecting portions 106, 116, ... on the lower surfaces of the second lead electrodes 115, 125, ..., the first lead electrodes 104, 114, 124, ... and the second lead electrodes 115, 125, ... Are electrically connected to each other. In this way, adjacent solar cells 101, 111, 121,... Are electrically connected in series.
[0009]
Further, the solar cells 101, 111, 121,... Electrically connected in series are sandwiched between a pair of planar members 107 and 108 made of a glass plate, a plastic plate, a resin film or the like, and a pair of surfaces. Between the members 107 and 108, a sealing material 109 made of a thermoplastic resin such as ethylene vinyl acetate copolymer resin (EVA) is filled so as to enclose the solar cells 101, 111, 121,. Has been. In this manner, a solar cell module including a plurality of solar cells electrically connected in series is configured.
[0010]
Next, with reference to FIG. 11 and FIG. 12, the manufacturing process of the conventional solar cell module is demonstrated.
[0011]
As shown in FIG. 11 and FIG. 12, first, a pair of stripes arranged in parallel with each other using silver paste on the upper surfaces of the solar cells 101, 111, 121,. Forming first collector electrodes 102, 112, 122,... Composed of first collector bus bar portions 102a, 112a, 122a,... And first collector electrode fingers 102b, 112b, 122b,. To do. Similarly, on the lower surface of the solar cells 101, 111, 121,..., A pair of striped second collector electrode bus bar portions arranged in parallel to each other and a large number using silver paste by a method such as screen printing. Second collector electrodes 103, 113, 123,... Made up of thin-line second collector electrode fingers are formed.
[0012]
Next, by a method such as soldering, a pair of first lead electrodes 104, 114, which are made of copper foil and arranged in parallel to each other on the upper surface of the first collector bus bar portions 102a, 112a, 122a,. Are electrically connected to each other. Further, a pair of second lead electrodes 105, 115, 125, made of copper foil and arranged in parallel to each other on the lower surface of the second collector electrode bus bar portion of the second collector electrodes 103, 113, 123,. Are electrically connected to each other. The solar cells 101, 111, 121,... Are arranged in a plane at a predetermined interval, and soldering or the like is performed at the connection portions 106, 116,... On the lower surfaces of the second lead electrodes 115, 125,. The first lead electrodes 104, 114, 124,... And the second lead electrodes 115, 125,... Are electrically connected, and the solar cells 101, 111, 121,. .
[0013]
Finally, solar cells 101, 111, 121,... Are electrically connected in series between a pair of planar members 107 and 108 made of a glass plate, a plastic plate, a resin film, or the like. At this time, a sealing material made of a sheet-like thermoplastic resin that becomes the sealing material 109 is interposed between the members 107 and 108 so as to sandwich the solar cells 101, 111, 121,. The sheet-like sealing material is melted and crosslinked by pressing and heating. Thereby, the sealing material 109 is filled between the members 107 and 108 so as to encapsulate the solar cells 101, 111, 121,. In this way, a conventional solar cell module is manufactured.
[0014]
[Problems to be solved by the invention]
As described above, in the conventional solar cell module, as shown in FIG. 11, the electrical connection between the first lead electrodes 104, 114, 124,... And the second lead electrodes 115, 125,. Are carried out by a method such as soldering at the connection portions 106, 116, ... on the lower surfaces of the second lead electrodes 115, 125, ... located on the lower surfaces of the batteries 111, 121, ..., respectively.
[0015]
However, the electrical connection between the lead electrodes described above is based on the pressure applied when the soldering iron is pressed in order to perform soldering while pressing the soldering iron onto the lower surface of the solar cells 111, 121,. 111, 121,... May break or cause scratches and dirt on the lower surface of the solar cells 111, 121,. As a result, the electrical connection between the solar cells may be interrupted, and the output of the solar cells 111, 121,... May be reduced, the output characteristics of the entire solar cell module may be reduced, and the manufacturing yield may be reduced. There was a problem.
[0016]
In addition, in the conventional solar cell module, for example, when replacing the solar cell 111 with damaged or deteriorated characteristics, the first lead electrode 104 is removed from the second lead electrode 115 at the connection portion 106 on the lower surface of the solar cell 111. The first lead electrode 114 also needs to be removed from the connection portion 116 on the lower surface of the solar cell 121. In order to perform such removal while pressing the soldering iron on the lower surface of the solar cell, not only the solar cell 111 to be replaced but also the solar cell 121 that does not need to be replaced by the pressure applied when the soldering iron is pressed. , Cracks, scratches and dirt may occur, resulting in a decrease in production yield. In addition, when performing the removal work so as not to cause such cracks and scratches, it is necessary to pay attention to the pressure with which the soldering iron is pressed, so that there is a problem that the work efficiency becomes very poor.
[0017]
In the conventional solar cell module, the first lead electrodes 104, 114, 124,... And the second lead electrodes 115, 125, at the connection portions 106, 116,. Are overlapped with each other, so that the thickness is increased compared to locations other than the connecting portions 106, 116,..., And steps or protrusions are generated by the solder used for electrical connection. As a result, the member 108 on the lower surface of the connecting portions 106, 116,... Swells, or bubbles are generated between the solar cells 111, 121,. There was a problem that the appearance deteriorated.
[0018]
Furthermore, in the conventional solar cell module, since the adjacent solar cells are electrically connected only by the first lead electrodes 104, 114, 124,..., The mechanical strength is not so high. For this reason, during the process of sealing the solar cells 101, 111, 121,... With the sealing material 109 between the members 107 and 108 described above, the solar cells are pulled by the melting and crosslinking of the sealing material. Stress is generated, and the interval between the solar cells easily changes. Thereby, there exists a possibility that adjacent solar cells may contact, and there existed a problem that the output of a solar cell module fell by such contact.
[0019]
The present invention has been made to solve the above problems,
One object of the present invention is to provide a solar cell module with good output characteristics and appearance without causing a reduction in manufacturing yield.
[0020]
Still another object of the present invention is to provide a method for manufacturing a solar cell module that can easily manufacture a solar cell module with good output characteristics and appearance without causing a decrease in manufacturing yield. .
[0021]
[Means for Solving the Problems]
In order to achieve the above object, a solar cell module according to a first aspect of the present invention includes a first solar cell and a second solar cell arranged in a plane at a predetermined interval, and a first solar cell module. A first lead electrode attached on an upper surface showing one conductivity type, a second lead electrode attached on a lower surface showing a second conductivity type of the second solar cell, a first solar cell, and a second solar cell; Between, the 1st lead electrode and the 2nd lead electrode are provided with the connection part electrically connected. The “lead electrode” in the present invention means a conductive member made of a sheet-like thin metal plate and a thin wire-like metal wire. Each lead electrode may include a plurality of lead electrodes.
[0022]
In the solar cell module according to the first aspect, as described above, the first lead electrode and the second lead electrode are electrically connected in the connecting portion located between the first solar cell and the second solar cell. This eliminates the need for electrical connection between the first lead electrode and the second lead electrode on the lower surface of the second solar cell. As a result, no pressure is applied to the second solar cell when the lead electrodes are electrically connected to each other. Therefore, cracks in the second solar cell, scratches on the lower surface of the second solar cell, and generation of dirt are prevented. Can be suppressed. As a result, a solar cell module with good manufacturing yield and output characteristics can be obtained. In addition, since no step due to the overlapping of the lead electrodes occurs on the lower surface of the solar cell, the swelling of the solar cell module on the lower surface of the solar cell is reduced. Thereby, a solar cell module with a good appearance can be obtained.
[0023]
In addition, when replacing defective solar cells from a plurality of electrically connected solar cells, it is only necessary to remove the lead electrode at the connecting portion provided between the solar cells. Thus, there is no need to remove the lead electrode on the lower surface of the solar cell. As a result, the replacement of the solar cell is facilitated, and cracking of the solar cell, damage on the lower surface of the solar cell, and generation of dirt can be suppressed.
[0024]
The solar cell module according to the first aspect preferably further includes a connection member that connects at least one of the first lead electrode and the second lead electrode. If comprised in this way, the mechanical strength of the 1st lead electrode and 2nd lead electrode which electrically connect a 1st solar cell and a 2nd solar cell can be improved. Thereby, since it can suppress that the space | interval of a 1st solar cell and a 2nd solar cell changes during a module formation process, it prevents that adjacent solar cells contact, and a fall of an output characteristic is reduced. Can be suppressed.
[0025]
In the solar cell module according to the first aspect, preferably, the connection member has conductivity. If comprised in this way, since a connection member and at least any one of a 1st lead electrode and a 2nd lead electrode are electrically connected, a 1st solar cell and a 2nd solar cell are a some 1st lead electrode and When electrically connected by the second lead electrode, the current flowing through the plurality of first lead electrodes and second lead electrodes can be balanced. As a result, it is possible to suppress a decrease in output characteristics due to an unbalance of currents flowing through the plurality of first lead electrodes and second lead electrodes.
[0026]
In the solar cell module according to the first aspect, the connection member preferably has a connection portion. If comprised in this way, since each lead electrode can be electrically connected to a connection member, it is not necessary to electrically connect each lead electrode directly. Thereby, electrical connection between the first lead electrode and the second lead electrode can be more easily performed.
[0027]
In the solar cell module according to the first aspect, preferably, at least one of the first lead electrode and the second lead electrode is made of a metal wire. In the present invention, the “metal wire” means a conductive member made of a thin metal wire. If comprised in this way, a reactive power generation area | region can be made further smaller by making the lead electrode by the side of the light-receiving surface of a solar cell into a metal wire, Therefore Output characteristics can be improved. In addition, by forming a large number of metal wires uniformly on the upper surface of the solar cell, a sufficient current collecting effect can be obtained by using them as lead electrodes. Thereby, since many metal wires can be utilized as a collector electrode finger part, it is not necessary to form a collector electrode finger part, and the manufacturing process of a solar cell module can be simplified.
[0028]
The solar cell module according to the first aspect preferably further includes a pair of planar members sandwiching the first solar cell and the second solar cell, and the pair of planar members, the first solar cell and the second solar cell. The space between the batteries is filled with a sealing material. If comprised in this way, while the mechanical strength of a solar cell module improves, since the penetration | invasion of the water | moisture content by rain etc. can be suppressed and waterproofness can be improved, a solar cell module with a favorable output characteristic can be obtained. .
[0029]
The manufacturing method of the solar cell module according to the second aspect of the present invention includes a step of arranging the first solar cell and the second solar cell in a plane shape at a predetermined interval, and a first conductivity type of the first solar cell. A step of attaching the first lead electrode on the upper surface shown, a step of attaching the second lead electrode on the lower surface showing the second conductivity type of the second solar cell, and a position between the first solar cell and the second solar cell. A connecting portion for electrically connecting the first lead electrode and the second lead electrode.
[0030]
In the method for manufacturing a solar cell module according to the second aspect, as described above, the first lead electrode and the second lead electrode are electrically connected to each other at the connection portion located between the first solar cell and the second solar cell. By electrically connecting, it is not necessary to make electrical connection between the first lead electrode and the second lead electrode on the lower surface of the second solar cell. As a result, no pressure is applied to the second solar cell when the lead electrodes are electrically connected to each other. Therefore, cracks in the second solar cell, scratches on the lower surface of the second solar cell, and generation of dirt are prevented. Can be suppressed. As a result, a solar cell module with good manufacturing yield and output characteristics can be easily manufactured. In addition, since the step due to the overlap of the lead electrodes does not occur on the lower surface of the solar cell, the swelling of the solar cell module on the lower surface of the solar cell is reduced. Thereby, a solar cell module with good appearance can be easily manufactured.
[0031]
In the method for manufacturing a solar cell module according to the second aspect, preferably, the step of arranging the second lead electrode so as to be substantially parallel to the arrangement surface on which the first solar cell and the second solar cell are arranged, And a step of extending the one lead electrode from the upper surface of the first solar cell toward the second solar cell and arranging the lead electrode so as to be substantially parallel to the arrangement surface at the connection portion. With this configuration, when the solar cells are arranged in a plane and are electrically connected, the first lead electrode and the second lead electrode can be easily brought into close contact with each other at the connection portion, so that the lead The electrodes can be easily electrically connected. Further, before and after the step of electrically connecting the first lead electrode and the second lead electrode, almost no deformation of each lead electrode occurs, so that the first lead electrode and the second lead electrode are electrically connected. In particular, excessive force does not act on the solar cell to which each lead electrode is attached. Thereby, damage to the solar cell can be suppressed.
[0032]
The manufacturing method of the solar cell module according to the third aspect of the present invention includes a step of arranging the first solar cell and the second solar cell in a plane shape at a predetermined interval, and a first conductivity type of the first solar cell. Attaching a lead wire from above the upper surface to the upper surface showing the first conductivity type of the second solar cell, and attaching a second lead electrode on the lower surface showing the second conductivity type of the second solar cell; In the connecting portion located between the first solar cell and the second solar cell, the step of electrically connecting the lead wire and the second lead electrode, and the lead wire between the connecting portion and the second solar cell. And a step of dividing. The “lead wire” in the present invention means a conductive member made of a continuous sheet-like metal thin plate and a fine wire-like metal wire that can be made into a lead electrode by the above-described dividing step.
[0033]
In the method for manufacturing a solar cell module according to the third aspect, as described above, the lead wire attached over the upper surface of each solar cell is divided between the solar cells to form the first lead electrode. Therefore, it is not necessary to attach the first lead electrode to each solar cell separately. Thereby, simplification of a manufacturing process and manufacturing cost can be reduced.
[0034]
Preferably, the method for manufacturing a solar cell module according to the second and third aspects further includes a step of connecting at least one of the first lead electrode or the lead wire and the second lead electrode with a connecting member. Yes. If comprised in this way, the mechanical strength of the 1st lead electrode and 2nd lead electrode which electrically connect a 1st solar cell and a 2nd solar cell can be improved. Thereby, since it can suppress that the space | interval of a 1st solar cell and a 2nd solar cell changes during a module formation process, it prevents that adjacent solar cells contact, and a fall of an output characteristic is reduced. Can be suppressed. In the above case, the connecting member preferably has conductivity. If comprised in this way, since a connection member and at least any one of a 1st lead electrode and a 2nd lead electrode are electrically connected, a 1st solar cell and a 2nd solar cell are a some 1st lead electrode and When electrically connected by the second lead electrode, the current flowing through the plurality of first lead electrodes and second lead electrodes can be balanced. As a result, it is possible to easily manufacture a solar cell module that can suppress a decrease in output characteristics due to imbalance of currents flowing through the plurality of first lead electrodes and second lead electrodes.
[0035]
A method for manufacturing a solar cell module according to a fourth aspect of the present invention includes a step of arranging a first solar cell, a second solar cell, and a conductive connecting member in a planar shape at a predetermined interval, and a first sun Attaching the first lead wire over the upper surface showing the first conductivity type of the battery, over the upper surface of the connecting member and over the upper surface showing the first conductivity type of the second solar cell, and connecting the first lead wire with the connecting member The step of dividing between the second solar cell, the lower surface showing the second conductivity type of the first solar cell, the lower surface of the connecting member, and the lower surface showing the second conductivity type of the second solar cell. A step of attaching two lead wires, and a step of dividing the second lead wire between the first solar cell and the connecting member.
[0036]
In the method for manufacturing a solar cell module according to the fourth aspect, as described above, the lead wires attached over the upper surface and the lower surface of the first solar cell, the second solar cell, and the connection member are connected to the solar cell and the connection member. , The first lead electrode and the second lead electrode can be attached to each solar cell and the first lead electrode and the second lead electrode can be electrically connected at the same time. It is possible to easily manufacture a solar cell module capable of simplifying and reducing the manufacturing cost.
[0037]
In the manufacturing method of the solar cell module, preferably, the step of sandwiching the first solar cell and the second solar cell by the pair of planar members, the pair of planar members, the first solar cell, and the second solar cell. And a step of filling the gap with a sealing material. If comprised in this way, while the mechanical strength of a solar cell module improves, the penetration | invasion of the water | moisture content by rain etc. can be suppressed and waterproofness can be improved, Therefore A solar cell module with a favorable output characteristic is manufactured easily. be able to.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0039]
(First embodiment)
This 1st Embodiment demonstrates the solar cell module provided with the several solar cell electrically connected in series by the lead electrode which consists of metal foil. In addition, the size of the solar cell module of this embodiment is about 1.3 m × about 0.9 m × about 8 mm.
[0040]
FIG. 1 is a cross-sectional view showing the structure of a solar cell module according to a first embodiment of the present invention in which a plurality of solar cells are electrically connected in series. FIG. 2 is a view for explaining the upper surface of the solar cells electrically connected in series and the connection portion where the lead electrodes are electrically connected in the solar cell module according to the first embodiment of the present invention. It is a top view. The structure of the solar cell module of the present invention will be described below with reference to FIGS.
[0041]
As shown in FIGS. 1 and 2, solar cells 1, 11, 21,... Having a size of about 100 mm square × about 200 μm thickness have n-type regions 1 n, 11 n, 21 n,. The p-type polycrystalline Si wafers 1p, 11p, 21p,... are arranged at an interval of about 5 mm. Here, the solar cells 1 and 11 are examples of the “first solar cell” and the “second solar cell” of the present invention, respectively.
[0042]
Moreover, on the upper surface of the solar cells 1, 11, 21,..., The first collector electrodes 2, 12, 22,... Formed using silver paste are on the lower surface of the solar cells 1, 11, 21,. Are formed with second collector electrodes 3, 13, 23,... Formed using silver paste, respectively.
[0043]
The first collector electrodes 2, 12, 22,... Have a line width of about 1.5 mm, and a pair of striped first collector electrode bus bar portions 2a, 12a arranged in parallel with each other at an interval of about 60 mm. , 22a,... (In FIG. 2, on the lower surface of first lead electrodes 4, 14, 24,... Described later, and indicated by dotted lines) and first collector electrode bus bar portions 2a, 12a, 22a,. First collector electrode finger portions 2b, 12b, and 22b in which about 50 (partially omitted in FIG. 2) comb-like thin wire electrodes extending in an orthogonal direction and having a line width of about 120 μm are arranged. ... The second collector electrodes 3, 13, 23,... Have a line width of about 3 mm, and are arranged in parallel with each other at an interval of about 60 mm, as with the first collector electrodes 2, 12, 22,. And a pair of striped second collector electrode bus bar portions, and about 100 comb-shaped fine wire electrodes having a line width of about 120 μm extending in a direction substantially orthogonal to the second collector electrode bus bar portions. A second collector electrode finger portion.
[0044]
On the upper surfaces of the first collector electrode bus bar portions 2a, 12a, 22a,..., Copper foil (metal foil) having a thickness of about 200 μm and a line width of W1 (about 1.5 mm) is arranged in parallel to each other. A pair of stripe-shaped first lead electrodes 4, 14, 24,... Are formed respectively. Further, the lower surface of the second collector electrode bus bar portion of the second collector electrodes 3, 13, 23,... Is made of a copper foil (metal foil) having a thickness of about 100 μm and a line width of W2 (about 3 mm). A pair of striped second lead electrodes 5, 15, 25,... Arranged in parallel to each other are respectively formed. The second lead electrodes 5, 15, 25,. It is formed only on the lower surface of the electrode bus bar portion.
[0045]
Next, in order to describe in detail the electrical connection between adjacent solar cells, the electrical connection between the solar cells 1, 11, 21,... Will be described with reference to FIGS.
[0046]
The second lead electrodes 15, 25,... Are arranged in a straight line so as to be substantially parallel to the arrangement surface on which the solar cells 1, 11, 21,. Are projected L2 (about 3 mm) toward the solar cells 1, 11,... The first lead electrodes 4, 14, 24,... Extend L1 (about 5 mm) from the upper surface and end portions of the solar cells 1, 11, 21,. .. Are substantially parallel to the second lead electrodes 15, 25,... On the upper surfaces of the second lead electrodes 15, 25,. It is bent and arranged like this. The first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,... Are electrically connected to the solar cells 1, 11, 21. Are electrically connected in series.
[0047]
The solar cells 1, 11, 21,... Electrically connected in series as described above are a pair of surfaces made of a glass plate or plastic plate having a thickness of about 3 mm, a resin film having a thickness of about 0.1 mm, or the like. Are sandwiched between the pair of planar members 7 and 8 and between the pair of planar members 7 and 8, so that the solar cells 1, 11, 21,. A sealing material 9 made of a thermoplastic resin such as vinyl copolymer resin (EVA) is filled. In this manner, a solar cell module including a plurality of solar cells electrically connected in series is configured.
[0048]
Next, with reference to FIG. 1 and FIG. 2, the manufacturing process of the solar cell module by 1st Embodiment of this invention is demonstrated.
[0049]
As shown in FIGS. 1 and 2, a pair of stripes arranged in parallel to each other by applying a silver paste on the upper surface of solar cells 1, 11, 21,... By a method such as screen printing and drying. The first collector electrodes 2, 12, 22,... Each including the first collector electrode bus bar portion and the first collector electrode finger portion including about 50 fine wire electrodes are formed. Similarly, a pair of striped second collector electrodes arranged parallel to each other by applying and drying a silver paste on the lower surface of the solar cells 1, 11, 21,... By a method such as screen printing. Second collector electrodes 3, 13, 23,... Each including a bus bar portion and a second collector electrode finger portion including approximately 100 thin wire electrodes are formed.
[0050]
Next, the upper surfaces of the first collector electrode bus bar portions 2a, 12a, 22a,... Of the first collector electrodes 2, 12, 22,. Are electrically connected to the pair of stripe-shaped first lead electrodes 4, 14, 24,. Further, a pair of striped second lead electrodes 5 made of copper foil (metal foil) and arranged in parallel on the lower surface of the second collector electrode bus bar portion of the second collector electrodes 3, 13, 23,. , 15, 25,... Are electrically connected to each other.
[0051]
Here, the second lead electrodes 15, 25,... Protrude L 2 (about 3 mm) toward the adjacent solar cells 1, 11, 21,. Are arranged in a straight line so as to be substantially parallel to the arrangement surface on which the solar cells 1, 11, 21,. The first lead electrodes 4, 14, 24,... Extend L1 (about 5 mm) from the upper surface and end portions of the solar cells 1, 11, 21,. .. Are substantially parallel to the second lead electrodes 15, 25,... On the upper surfaces of the second lead electrodes 15, 25,. As shown in FIG.
[0052]
Next, the solar cells 1, 11, 21,... Are arranged in a planar shape with an interval of about 5 mm, and the connection portions 6, 16,. The first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,. The first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25 from the upper surface side of the solar cells 1, 11, 21,. Are electrically connected to each other. In this way, the solar cells 1, 11, 21,... Are electrically connected in series.
[0053]
Finally, solar cells 1, 11, 21,... Electrically connected in series are sandwiched between a pair of planar members 7 and 8 made of a glass plate, a plastic plate, or a resin film. At this time, a sealing material made of a sheet-like thermoplastic resin that becomes the sealing material 9 is interposed between the pair of planar members 7 and 8 so as to sandwich the solar cells 1, 11, 21,. The sheet-like sealing material is melted and cross-linked by pressurizing and heating from above and below. Thereby, the sealing material 9 is filled between the pair of planar members 7 and 8 so as to encapsulate the solar cells 1, 11, 21,. Thus, the solar cell module according to the first embodiment of the present invention is manufactured.
[0054]
In the first embodiment, as described above, the first lead electrodes 4, 14, 24,... And the second lead electrodes 4, 16,... Positioned between the adjacent solar cells 1, 11, 21,. The lead electrodes 15, 25,... Are electrically connected, so that the lead electrodes need not be electrically connected to each other on the lower surface of the solar cells 11, 21,. As a result, no pressure is applied to each solar cell when electrical connection between the lead electrodes is performed, so that cracking of each solar cell, scratches on the lower surface of each solar cell, and generation of dirt are suppressed. Can do. As a result, a solar cell module with good manufacturing yield and output characteristics can be obtained. In addition, since no step due to the overlapping of the first lead electrode and the second lead electrode occurs on the lower surface of each solar cell, the swelling of the solar cell module on the lower surface of each solar cell is reduced. Thereby, a solar cell module with a good appearance can be obtained.
[0055]
Further, when replacing a defective solar cell from a plurality of solar cells electrically connected in series, the first lead electrodes 4 and 14 at the connection portions 6, 16,... Provided between the solar cells. , 24,... And the second lead electrodes 15, 25,... Need only be removed, and there is no need to remove the lead electrodes on the lower surface of the solar cell as in the prior art. As a result, the replacement of the solar cell is facilitated, and cracking of the solar cell, scratches on the lower surface of the solar cell, and generation of dirt can be suppressed.
[0056]
In the first embodiment, the second lead electrodes 5, 15, 25,... Are arranged linearly so as to be substantially parallel to the arrangement surface on which the solar cells 1, 11, 21,. In addition, L2 (about 3 mm) protrudes from the lower surface and end portions of the solar cells 11, 21, ... toward the solar cells 1, 11, .... In addition, the first lead electrodes 4, 14, 24,... Extend from the upper surface and end portions of the solar cells 1, 11, 21,. It arrange | positions so that it may become substantially parallel to the said arrangement | positioning surface. Thus, when the solar cells 1, 11, 21,... Are arranged in a plane and are electrically connected, the solar cells 1, 11, 21,... And the connection portions 6, 16,. Because of the arrangement, the first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,. As a result, sufficient pressure can be applied to the connecting portions 6, 16,... With stability, so that the electricity between the first lead electrodes 4, 14, 24,. Connection can be made easily and satisfactorily. In addition, since there is almost no deformation of the lead electrodes before and after the electrical connection process between the lead electrodes, it is excessive for the solar cell to which the lead electrodes are attached even when the lead electrodes are electrically connected. There is no force acting. Thereby, damage to the solar cell can be suppressed.
[0057]
In the first embodiment, a pair of planar members 7 and 8 sandwiching the solar cells 1, 11, 21,... And the pair of planar members 7 and 8 and the solar cells 1, 11, 21 are provided. ,... Are filled with a sealing material 9. As a result, the mechanical strength of the solar cell module is improved and the water penetration due to rain or the like can be suppressed and the waterproof property can be improved, so that a solar cell module with good output characteristics and manufacturing yield can be obtained.
[0058]
In the first embodiment, the first lead electrodes 4, 14, 24,... And the second lead electrodes 5, 15, 25,... Are made of a sheet-like thin metal plate made of copper foil (metal foil). ing. Thus, before the lead electrodes are electrically connected to each other, the connection is made in advance from the upper surface and end portions of the solar cells 1, 11, 21,... Toward the solar cells 11, 21,. The parts 6, 16,... Can be easily molded into a shape that is substantially parallel to the arrangement surface. Further, the line width W1 (about 1.5 mm) of the first lead electrodes 4, 14, 24,... Is smaller than the line width W2 (about 3 mm) of the second lead electrodes 5, 15, 25,. When the first lead electrodes 4, 14, 24,... Are superposed on the second lead electrodes 15, 25,..., The state where the solar cells 1, 11, 21,. In addition, it is possible to easily perform electrical connection work by soldering. Thereby, poor electrical connection between the lead electrodes can be prevented. In this case, the line width of the first lead electrodes 4, 14, 24,... Is smaller than the line width of the second lead electrodes 5, 15, 25,. It is preferable that the upper surface of 1, 11, 21,. Further, by adjusting the thickness of each lead electrode according to the line width of the first lead electrodes 4, 14, 24,... And the second lead electrodes 5, 15, 25,. A cross-sectional area can be secured. Moreover, in the said 1st Embodiment, since the cross-sectional area of each lead electrode attached on the upper surface and lower surface of each solar cell is made comparable, the said lead electrode was attached on the upper surface and lower surface of a solar cell, respectively. Even in the case, the solar cell is hardly warped, and each solar cell can be easily arranged in a planar shape. Thereby, the electrical connection between the first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,.
[0059]
Moreover, in the said 1st Embodiment, projection length L1 to the said arrangement | positioning surface of the part which 1st lead electrode 4, 14, 24, ... protrudes on the upper surface of solar cell 1, 11, 21, ...... from an edge part. (About 5 mm) is based on the projection length L2 (about 3 mm) of the portion where the second lead electrodes 15, 25,... Protrude from the lower surface of the solar cells 1, 11, 21,. Also long. , When the solar cells 1, 11, 21,... Are arranged so that the first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,. .. Between the first lead electrodes 4, 14, 24,... Is not smaller than the projected length L 1 of the first lead electrodes 4, 14, 24,. 1, 11, 21,... Can each be a predetermined amount (ie, approximately L 1 −L 2 = about 2 mm). As a result, the second lead electrodes 15, 25,... Do not contact the lower surface of the solar cells 1, 11, 21,... And the second lead electrodes 5, 15, 25,. A short circuit can be prevented.
[0060]
(Second Embodiment)
This 2nd Embodiment demonstrates the solar cell module provided with the several solar cell electrically connected in series by the 1st lead electrode which consists of metal wires, and the 2nd lead electrode which consists of metal foil. In addition, the size of the solar cell module of this embodiment is about 1.3 m × about 0.9 m × about 8 mm.
[0061]
FIG. 3 is a cross-sectional view illustrating a structure of a solar cell module according to a second embodiment of the present invention in which a plurality of solar cells are electrically connected in series. FIG. 4 is a view for explaining the upper surface of the solar cells electrically connected in series and the connection portion where the lead electrodes are electrically connected in the solar cell module according to the second embodiment of the present invention. It is a top view. With reference to FIG. 3 and FIG. 4, the structure of the solar cell module of the present invention will be described below. 3 and FIG. 4, the same parts as those in FIG. 1 and FIG.
[0062]
In the solar cell module according to the second embodiment, solar cells 1, 11, 21,... Similar to the solar cell module of the first embodiment are arranged with an interval of about 5 mm. Here, the solar cells 1 and 11 are examples of the “first solar cell” and the “second solar cell” of the present invention, respectively.
[0063]
On the upper surface of the solar cells 1, 11, 21,. 1 lead electrodes 34, 44, 54,... Are respectively formed. Further, second lead electrodes 35, 45, 55,... Made of copper foil (metal foil) and having a thickness of about 100 μm are formed on substantially the entire lower surface of the solar cells 1, 11, 21,. ing. The first lead electrodes 34, 44, 54,... And the second lead electrodes 35, 45, 55,. Each is attached by a conductive adhesive kneaded with silver particles having a diameter.
[0064]
Next, in order to explain the electrical connection between adjacent solar cells in detail, the electrical connection between the solar cells 1, 11, 21,... Will be described with reference to FIGS.
[0065]
The second lead electrodes 45, 55,... Are arranged in a straight line so as to be substantially parallel to the arrangement surface on which the solar cells 1, 11, 21,. Are projected toward the solar cells 1, 11, 21,... In addition, the first lead electrodes 34, 44, 54,... Are formed over substantially the entire length on the upper surface of the solar cells 1, 11, 21,. Are connected to the solar cells 11, 21,..., And are connected between the solar cells 1, 11, 21,. Are arranged so as to be substantially parallel to the second lead electrodes 45, 55,. The first lead electrodes 34, 44, 54,... And the second lead electrodes 45, 55,... Are electrically connected to the solar cells 1, 11, 21. Are electrically connected in series.
[0066]
Moreover, in the solar cell module according to the present embodiment, as in the solar cell module of the first embodiment, the solar cells 1, 11, 21,... That are electrically connected in series as described above have a pair of planar shapes. .. Are sandwiched between members 7 and 8 and filled with sealing material 9 so as to enclose solar cells 1, 11, 21,. In this manner, a solar cell module including a plurality of solar cells electrically connected in series is configured.
[0067]
FIG. 5 is a cross-sectional view for explaining a manufacturing process of the solar cell module according to the second embodiment of the present invention. A manufacturing process of the solar cell module according to the second embodiment of the present invention will be described with reference to FIGS.
[0068]
As shown in FIG. 5 (a), copper coated with a conductive adhesive in which silver particles having a diameter of several μm are kneaded into an epoxy resin is applied to substantially the entire bottom surface of the solar cells 1, 11, 21,. The second lead electrodes 35, 45, 55,... Made of foil (metal foil) and having a thickness of about 100 μm are brought into contact with each other. Here, the second lead electrodes 45, 55,... Protrude from the lower surfaces and end portions of the solar cells 11, 21,... Toward the adjacent solar cells 1, 11, 21,. , 11, 21,... Are arranged in a straight line so as to be substantially parallel to the arrangement surface on which are arranged. Next, while the flat heater heated to about 80 ° C. is pressed against the second lead electrodes 35, 45, 55,..., The temperature is raised to about 200 ° C., and the second lead electrodes 35, 45, 55,. Heat. Thereby, the conductive adhesive is thermally cured, and the second lead electrodes 35, 45, 55,... Are electrically connected to the lower surfaces of the solar cells 1, 11, 21,. The solar cells 1, 11, 21,... Are arranged in a planar shape with an interval of about 5 mm.
[0069]
Next, on the upper surface of the solar cells 1, 11, 21,..., About 50 having a diameter of about 50 μm obtained by applying a conductive adhesive obtained by kneading silver particles having a diameter of several μm to an epoxy resin to the surface. A thin lead wire 50 made of copper wire (metal wire) is brought into contact. At this time, as shown in FIG. 5A, the lead wire 50 is loosened and attached between the solar cells 1, 11, 21,.
[0070]
Next, as shown in FIG. 5 (b), the lead wire 50 is bent between the solar cells 1, 11, 21,... And the connection portion 6 on the upper surface of the second lead electrodes 45, 55,. Are brought into contact with the connecting portions 6, 16,. Are heated to about 200 ° C. while a flat heater heated to about 80 ° C. is pressed against the lead wire 50 on the upper surfaces of the solar cells 1, 11, 21,. Then, the lead wire 50 is heated for a predetermined time. Thereby, the conductive adhesive is thermally cured, and the lead wire 50 and the solar cells 1, 11, 21,... And the second lead electrodes 35, 45, 55,.
[0071]
Furthermore, as shown in FIG.5 (b), the lead wire 50 between the connection part 6,16, ... and the upper surface edge part of the solar cell 11,21, ... is a rotary cutter in the position of the arrow in a figure. The first lead electrodes 34, 44, 54,... Are formed as shown in FIGS. In this way, as shown in FIGS. 3 and 4, the solar cells 1, 11, 21,... Are electrically connected in series.
[0072]
Finally, the solar cells 1, 11, 21,... Electrically connected in series between the pair of planar members 7 and 8 are sandwiched by the same process as in the first embodiment, and the solar cells 1, 11 are sandwiched. The solar cell module according to the second embodiment of the present invention is manufactured by filling the sealing material 9 so as to encapsulate.
[0073]
In the second embodiment, as described above, the first lead electrodes 34, 44, 54,... Are composed of fine metal wires made of copper wires (metal wires) having a diameter of about 50 μm. By making the upper surface side of the solar cells 1, 11, 21,... To which the first lead electrodes 34, 44, 54,. In addition, since a large number of first lead electrodes 34, 44, 54,... Are uniformly formed on the upper surfaces of the solar cells 1, 11, 21,. It is not necessary to form collector electrode fingers. Thereby, the reactive power generation region can be further reduced, so that the output characteristics can be improved and the manufacturing process of the solar cell module can be simplified.
[0074]
In the second embodiment, the first lead electrodes 34, 44, 54,... Are electrically connected to the same second lead electrodes 45, 55,. Thereby, since the balance of the electric current which flows on about 50 copper wires which comprise each 1st lead electrode can be maintained, the fall of the output characteristic by the imbalance of an electric current can be suppressed.
[0075]
In the second embodiment, the first lead electrodes 34, 44, 54,... And the second lead electrodes 35, 45, 55,. Since they are formed on the upper and lower surfaces, it is not necessary to form collector electrodes having collector electrode bus bar portions and collector electrode finger portions on the upper and lower surfaces of solar cells 1 and 11, respectively. Thereby, the manufacturing process can be simplified and the manufacturing cost can be reduced.
[0076]
In the second embodiment, the upper surfaces of the solar cells 1, 11, 21,... And the connection portions 6, 16,... Are electrically connected by a thin lead wire 50 made of copper wire (metal wire). After that, the lead wires 50 between the connection portions 6, 16,... And the upper end portions of the solar cells 11, 21,. This forms the first lead electrodes 34, 44, 54,... On the solar cells 1, 11, 21,..., And the first lead electrodes 34, 44, 54,. Since electrical connection with the second lead electrodes 45, 55,... Can be performed at the same time, the manufacturing process can be simplified and the manufacturing cost can be reduced.
[0077]
(Third embodiment)
In the third embodiment, in addition to the first embodiment, a solar cell module further including a connecting member that electrically connects each lead electrode between adjacent solar cells will be described. In addition, the size of the solar cell module of this embodiment is about 1.3 m × about 0.9 m × about 8 mm.
[0078]
FIG. 6 is a cross-sectional view showing the structure of a solar cell module according to a third embodiment of the present invention in which a plurality of solar cells are electrically connected in series. FIG. 7 is a view for explaining a top surface of solar cells electrically connected in series and a connection portion where lead electrodes are electrically connected in the solar cell module according to the third embodiment of the present invention. It is a top view. The structure of the solar cell module of the present invention will be described below with reference to FIGS. 6 and 7, the same reference numerals are given to the same components as those in FIGS. 1 and 2, and the description thereof is omitted.
[0079]
The solar cell module according to the third embodiment includes solar cells 1, 11, 21,... Similar to the solar cell module of the first embodiment, and the first lead electrode 4, at the connection portions 6, 16,. Are electrically connected in series to each other by the electrical connection between the second lead electrodes 15, 25,. Here, the solar cells 1 and 11 are examples of the “first solar cell” and the “second solar cell” of the present invention, respectively.
[0080]
Further, on the upper surfaces of the connecting portions 6, 16,..., A size of about 2 mm wide × about 60 mm long × about 200 μm made of a lead-free metal foil such as Sn—Ag—Cu based by a method such as soldering. Are electrically connected to each other, and the first lead electrodes 4, 14, 24,... And the second leads 15, 25 each made of a pair of copper foils (metal foils). , ... are electrically connected.
[0081]
Moreover, in the solar cell module according to the present embodiment, as in the solar cell module of the first embodiment, the solar cells 1, 11, 21,... That are electrically connected in series as described above have a pair of planar shapes. .. Are sandwiched between members 7 and 8 and filled with sealing material 9 so as to enclose solar cells 1, 11, 21,. In this manner, a solar cell module including a plurality of solar cells electrically connected in series is configured.
[0082]
Next, with reference to FIG. 6 and FIG. 7, the manufacturing process of the solar cell module by 3rd Embodiment of this invention is demonstrated.
[0083]
First, as shown in FIG. 6, the first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,. The solar cells 1, 11, 21,... Are electrically connected in series by being electrically connected to each other at the units 6, 16,.
[0084]
Next, in the connection parts 6, 16,... Where the first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,. The first lead electrodes 4, 14, 24,... Made of a pair of copper foils (metal foils) and the second lead electrodes 15, 25,. Connect electrically.
[0085]
Finally, the solar cells 1, 11, 21,... Connected in series between the pair of planar members 7 and 8 are sandwiched by the same process as in the first embodiment, and the solar cells 1, 11 are sandwiched. , 21... Are filled with the sealing material 9 to manufacture the solar cell module according to the third embodiment of the present invention.
[0086]
In the third embodiment, as described above, between the adjacent solar cells 1, 11, 21,..., The first lead electrodes 4, 14, 24,. Connection members 10, 20,... For connecting 15, 25,. This improves the mechanical strength of the first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,... Connected between the adjacent solar cells 1, 11, 21,. Therefore, it can suppress that the space | interval of the adjacent solar cells 1, 11, 21, and ... changes during a module formation process. Further, since the connection members 10, 20,... Have conductivity, the connection members 10, 20,..., The first lead electrodes 4, 14, 24,... And the second lead electrodes 5, 15, 25,. Are electrically connected to each other, so that the adjacent solar cells 1, 11, 21,... Are electrically connected by the plurality of first lead electrodes 4, 14, 24,. .., And the second lead electrodes 15, 25,..., And the current flowing through the plurality of first lead electrodes 4, 14, 24,. As a result, it is possible to suppress a decrease in output characteristics due to an unbalance of currents flowing through the plurality of first lead electrodes 4, 14, 24,... And the second lead electrodes 15, 25,.
[0087]
(Fourth embodiment)
In the fourth embodiment, a solar cell module including a plurality of solar cells electrically connected in series by a lead electrode made of a metal wire and a conductive connection member between adjacent solar cells will be described. . In addition, the size of the solar cell module of this embodiment is about 1.3 m × about 0.9 m × about 8 mm.
[0088]
FIG. 8 is a cross-sectional view showing the structure of a solar cell module according to a fourth embodiment of the present invention in which a plurality of solar cells are electrically connected in series. Moreover, FIG. 9 is a solar cell module according to the fourth embodiment of the present invention, for explaining the upper surface of the solar cells electrically connected in series and the connection portion where the lead electrodes are electrically connected. It is a top view. With reference to FIGS. 8 and 9, the structure of the solar cell module of the present invention will be described below. 8 and FIG. 9, the same parts as those in FIG. 3 and FIG.
[0089]
In the solar cell module according to the fourth embodiment, solar cells 1, 11, 21,... Similar to the solar cell module according to the first embodiment are arranged with an interval of about 5 mm. Here, the solar cells 1 and 11 are examples of the “first solar cell” and the “second solar cell” of the present invention, respectively.
[0090]
Further, between adjacent solar cells 1, 11, 21,..., A copper foil (metal foil) having substantially the same thickness as the solar cells 1, 11, 21,... Is about 2 mm wide × about 100 mm long × about The sheet-like connection members 30, 40,... Having a size of 200 μm are arranged on the same plane as the solar cells 1, 11, 21,.
[0091]
Next, in order to describe the electrical connection between adjacent solar cells in detail, the electrical connection between the solar cells 1, 11, 21,... Will be described with reference to FIGS.
[0092]
On the upper surface of the solar cells 1, 11, 21,. One lead electrode 64, 74, 84,... Is formed. The first lead electrodes 64, 74, 84,... Protrude from the upper surfaces and end portions of the solar cells 1, 11, 21,. Are electrically connected to the connection members 30, 40,... At the connection portions 30 a, 40 a,. On the lower surface of the solar cells 1, 11, 21,..., A copper wire (metal wire) made of about 50 copper wires (partially omitted in FIG. 9) having a diameter of about 50 μm arranged in parallel with each other. Two lead electrodes 65, 75, 85,... Are respectively formed. In addition, the second lead electrodes 75, 85,... Protrude from the lower surface and end portions of the solar cells 11, 21,... Toward the connection members 30, 40,. In the upper connection portions 30b, 40b, ..., the connection members 30, 40, ... are electrically connected. The first lead electrodes 64, 74, 84, ... and the second lead electrodes 65, 75, 85, ... are on the upper and lower surfaces of the solar cells 1, 11, 21, ... and the connection members 30, 40, ... Are attached by a conductive adhesive in which silver particles having a diameter of several μm are kneaded into an epoxy resin. Accordingly, the solar cells 1, 11, 21,... Are electrically connected in series by the first lead electrodes 64, 74, 84,... And the second lead electrodes 75, 85,. Has been.
[0093]
Moreover, in the solar cell module according to the present embodiment, as in the solar cell module of the first embodiment, the solar cells 1, 11, 21,... That are electrically connected in series as described above have a pair of planar shapes. .. Are sandwiched between members 7 and 8 and filled with sealing material 9 so as to enclose solar cells 1, 11, 21,. In this manner, a solar cell module including a plurality of solar cells electrically connected in series is configured.
[0094]
FIG. 10 is a cross-sectional view for explaining a manufacturing process for the solar cell module according to the fourth embodiment of the present invention. A manufacturing process of the solar cell module according to the fourth embodiment of the present invention will be described with reference to FIGS.
[0095]
First, as shown in FIG. 10 (a), the solar cells 1, 11, 21,... Are spaced apart by an interval of about 5 mm, and the connection members 30, 40 are interposed between the solar cells 1, 11, 21,. , ... are arranged.
[0096]
Next, as shown in FIG. 10 (b), the connection portions 30a, 40a,... And the lower surface on the upper and lower surfaces of the solar cells 1, 11, 21,. About 50 copper wires (metal wires) having a diameter of about 50 μm obtained by applying a conductive adhesive prepared by kneading silver particles having a diameter of several μm to an epoxy resin to the upper connection portions 30b, 40b,. The thin lead wires 50 and 60 made of are brought into contact with each other. Here, the lead wires 50 and 60 are examples of the “first lead wire” and the “second lead wire” of the present invention, respectively. Next, on the upper surface and the lower surface of the solar cells 1, 11, 21,... And the connection members 30, 40,..., About 200 ° C. with the flat heater heated to about 80 ° C. pressed against the lead wires 50 and 60. The lead wires 50 and 60 are heated for a predetermined time. Thereby, the conductive adhesive is thermally cured, and the lead wires 50 and 60 are electrically connected to the upper and lower surfaces of the solar cells 1, 11, 21,... And the connection members 30, 40,. To do.
[0097]
Next, as shown in FIG. 10B, the lead wire 50 between the connection portions 30a, 40a,... On the upper surface of the connection members 30, 40,. Are respectively cut and removed using a rotary cutter, laser, or the like at the position of the arrow in the figure, thereby forming first lead electrodes 64, 74, 84,... As shown in FIGS. . Further, the lead wire 60 between the connection portions 30b, 40b,... On the lower surface of the connection members 30, 40,... And the lower surface end portions of the solar cells 1, 11, 21,. The second lead electrodes 65, 75, 85,... Are formed by cutting and removing each using a rotary cutter, laser, or the like. In this way, as shown in FIGS. 8 and 9, the solar cells 1, 11, 21,... Are electrically connected in series.
[0098]
Finally, the solar cells 1, 11, 21,... Electrically connected in series between the pair of planar members 7 and 8 are sandwiched by the same process as in the other embodiments, and the solar cell 1, The solar cell module according to the fourth embodiment of the present invention is manufactured by filling the sealing material 9 so as to encapsulate 11, 21,.
[0099]
In the fourth embodiment, as described above, the connection members 30, 40,... Positioned between the solar cells 1, 11, 21,. .. And 30b, 40b,... To be connected. Thereby, the first lead electrodes 64, 74, 84,... And the second lead electrodes 65, 75, 85,... Made of copper wires (metal wires) having a fine diameter of about 50 μm are required to be directly electrically connected. Therefore, electrical connection between the lead electrodes can be easily performed. Further, the connection members 30, 40,... Maintain the balance of the currents flowing through the plurality of lead electrodes constituting the first lead electrodes 64, 74, 84,... And the second lead electrodes 65, 75, 85,. Therefore, it is possible to suppress a decrease in output characteristics due to current imbalance.
[0100]
Further, by dividing the lead wires 50 and 60 attached over each solar cell and the connection members 30, 40,... Between the respective solar cells and the connection members 30, 40,. , 21,... And the second lead electrodes 65, 75, 85,..., And the electrical connection of the lead electrodes via the connecting members 30, 40,. Since the connection can be performed simultaneously, a solar cell module capable of simplifying the manufacturing process and reducing the manufacturing cost can be easily manufactured.
[0101]
Moreover, since each lead electrode of each solar cell is comprised from the thin wire-shaped metal wire which consists of a copper wire (metal wire) which has a diameter of about 50 micrometers, which of the upper surface side and lower surface side of each solar cell is light-receiving surface However, the reactive power generation area can be reduced. Further, both sides can be light receiving surfaces. As a result, the output characteristics can be further improved. Further, a large number of first lead electrodes 64, 74, 84,... And second lead electrodes 65, 75, 85,... Are uniformly formed on the upper and lower surfaces of the solar cells 1, 11, 21,. Therefore, each has a sufficient current collecting effect, and it is not necessary to form the collecting electrode finger portion. Thereby, the reactive power generation region can be further reduced, so that the output characteristics can be improved and the manufacturing process of the solar cell module can be simplified.
[0102]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and all modifications are included in the meaning and scope equivalent to the scope of claims for patent.
[0103]
For example, in the first embodiment, the third embodiment, and the fourth embodiment, the number of the first lead electrodes and the second lead electrodes is the same, but the present invention is not limited to this, and the first lead electrode and the second lead electrode are the same. The number of 2-lead electrodes can be appropriately selected so that the output power is maximized.
[0104]
Further, in the first embodiment, the second embodiment, and the third embodiment, the first lead electrode is arranged to be bent toward the connection portion, and the second lead electrode is an arrangement in which each solar cell is arranged. However, the present invention is not limited to this, and the first lead electrode and the second lead electrode may be opposite in shape and arrangement.
[0105]
Further, in the first embodiment and the third embodiment, the first lead electrode is bent in advance, but the present invention is not limited to this. For example, as in the third embodiment, each lead electrode is solar After being electrically connected to the battery, it may be formed into a predetermined shape.
[0106]
Moreover, in the said 3rd Embodiment, although the one connection member was attached on the connection part to which the 1st lead electrode and the 2nd lead electrode were electrically connected, this invention is not restricted to this, A connection part A connecting member may be attached on the first lead electrode or the second lead electrode other than the above, and a plurality of connecting members may be attached at different positions on the first lead electrode or the second lead electrode.
[0107]
Moreover, in the said 4th Embodiment, although the 1st lead electrode and the 2nd lead electrode were electrically connected to the connection part on the upper surface and the lower surface of one electrical connection member, this invention is not limited to this. Instead, a plurality of connecting members that are electrically connected to the first lead electrode and the second lead electrode may be electrically connected to each other. For example, when a connection member in which two or more connection members are bonded together is used, the replacement operation can be easily performed by peeling and separating the bonded connection members when replacing the solar cell.
[0108]
Moreover, in the said 2nd Embodiment, although the 2nd lead electrode was formed in the substantially whole surface on the lower surface of each solar cell, this invention is not restricted to this, For example, like the said 1st Embodiment, on the lower surface of each solar cell. The second lead electrode may be formed only on a part of the lower surface of the solar cell.
[0109]
In the above embodiment, the lead electrodes are electrically connected to each other by a soldering method or a method using a conductive adhesive. However, the present invention is not limited to this, and methods such as screwing, crimping, and spot welding are used. It is also possible to use an electrical connection method.
[0110]
In each of the above embodiments, a metal foil and a metal wire made of copper are used as each lead electrode and each lead wire. However, the present invention is not limited to this, and Au, Ag, Al, Mo, Ni, W, etc. Low resistance materials such as other metals and their alloys can also be used. These lead electrodes and lead wires may be coated on the surface with other metals such as solder, Sn, Ni, Zn, and alloys thereof in order to facilitate surface protection and electrical connection work. As a coating method, methods such as melting, electrolysis or electroless plating, and vapor deposition can be used. In addition, each lead electrode and each lead wire can be adjusted to an appropriate elongation and strength by performing heat treatment to remove work hardening.
[0111]
Moreover, in the said 2nd Embodiment and 4th Embodiment, although the copper wire of about 50 micrometers was used as each lead electrode and each lead wire, this invention is not limited to this, It has moderate mechanical strength and electroconductivity. A fine metal wire can be used, and the diameter of the metal wire is preferably about 30 μm to about 100 μm. If the wire diameter is too thin, the mechanical strength is reduced and handling becomes difficult, and the conductivity is also lowered, so the output of the solar cell is lowered. Further, the cost is increased. Conversely, if the wire diameter is too thick, the reactive power generation area on the light-receiving surface side of each solar cell increases, resulting in an increase in optical loss, resulting in reduced solar cell conversion efficiency and output characteristics of the solar cell module. Decreases.
[0112]
Moreover, in the said 2nd Embodiment and 4th Embodiment, although the conductive adhesive which knead | mixed the silver particle which has a diameter of several micrometers in an epoxy resin was used, this invention is not limited to this, As a resin material, As the conductive fine particles, polyimide, acrylic, urethane, phenol, polyester, and other resins, metals such as Au, Cu, C, Mo, and Ni, alloys thereof, and mixtures thereof may be used. Furthermore, an appropriate organic solvent may be mixed in order to adjust the viscosity of the conductive adhesive. Further, the organic solvent may be evaporated before performing the heat curing.
[0113]
Moreover, the application | coating thickness of the said conductive adhesive can be suitably adjusted according to surface roughness and uneven | corrugated shape, such as a metal wire and a solar cell. If the size of the surface irregularities is about several μm to several tens μm, the coating thickness is preferably about 5 μm to 20 μm. For example, when the coating thickness is applied to a metal wire, the inner diameter is adjusted in a method in which a metal wire coated with a sufficient amount of conductive adhesive is passed through a hole having an appropriate inner diameter. Is possible.
[0114]
In the third embodiment, a Sn-Ag-Cu-based lead-free metal foil is used as the connection member in the fourth embodiment, but the present invention is not limited to this. Other metal foils and alloy foils such as Sn—Pb containing SUS and lead may be used. In addition, these connecting members may be coated on the surface with other metals such as solder, Sn, Ni, Zn, and alloys thereof in order to easily perform surface protection and electrical connection work. As a coating method, methods such as melting, electrolysis or electroless plating, and vapor deposition can be used. Furthermore, the connection member can be adjusted to an appropriate elongation or strength by performing heat treatment to remove work hardening.
[0115]
In each of the above embodiments, EVA, which is a thermoplastic resin, is used as a sealing material, and the sealing operation is performed by pressurizing and heating the EVA. However, the present invention is not limited thereto, A resin material can be used as a sealing material. In addition, a method of filling a sealing material by a method of pouring a fluid material between planar members can be used.
[0116]
In each of the above embodiments, a solar cell module using a solar cell using a polycrystalline p-type Si wafer has been described. However, the present invention is not limited to this, and an n-type Si wafer, a single crystal Si wafer, Solar cells made of other semiconductor materials such as crystalline semiconductors and compound semiconductors can also be used.
[0117]
Moreover, in each said embodiment, although the side surface of each solar cell is not specifically insulated, this invention is not limited to this, You may coat the insulating material which consists of resin etc. on the side surface of a solar cell. Thereby, even if each lead electrode contacts the side surface of the solar cell, electrical insulation can be maintained, so that there is no possibility that the output is reduced. In this case, the insulating material preferably has translucency.
[0118]
In the present invention, the light receiving surface of the solar cell module may be either the upper surface or the lower surface of each solar cell, and both surfaces may be light receiving surfaces.
[0119]
【The invention's effect】
As described above, according to the present invention, in a solar cell module including a plurality of solar cells electrically connected to each other by lead electrodes made of a conductive member such as a metal foil or a metal wire, the manufacturing yield is reduced. The solar cell module with good output characteristics and appearance can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing the structure of a solar cell module according to a first embodiment of the present invention in which a plurality of solar cells are electrically connected in series.
FIG. 2 is a top view for explaining a top surface of solar cells electrically connected in series and a connection portion where lead electrodes are electrically connected in the solar cell module according to the first embodiment of the present invention; is there.
FIG. 3 is a cross-sectional view showing a structure of a solar cell module according to a second embodiment of the present invention in which a plurality of solar cells are electrically connected in series.
FIG. 4 is a top view for explaining a top surface of solar cells electrically connected in series and a connection portion where lead electrodes are electrically connected in a solar cell module according to a second embodiment of the present invention. is there.
FIG. 5 is a cross-sectional view for explaining a manufacturing process of a solar cell module according to a second embodiment of the present invention.
FIG. 6 is a cross-sectional view showing the structure of a solar cell module according to a third embodiment of the present invention in which a plurality of solar cells are electrically connected in series.
FIG. 7 is a top view for explaining a top surface of solar cells electrically connected in series and a connection portion where lead electrodes are electrically connected in a solar cell module according to a third embodiment of the present invention. is there.
FIG. 8 is a cross-sectional view showing a structure of a solar cell module according to a fourth embodiment of the present invention in which a plurality of solar cells are electrically connected in series.
FIG. 9 is a top view for explaining a top surface of solar cells electrically connected in series and a connection portion where lead electrodes are electrically connected in a solar cell module according to a fourth embodiment of the present invention; is there.
FIG. 10 is a cross-sectional view for explaining a manufacturing process for a solar cell module according to a fourth embodiment of the present invention.
FIG. 11 is a cross-sectional view for explaining the structure of a conventional solar cell module in which a plurality of solar cells are electrically connected in series.
FIG. 12 is a top view for explaining a top surface of solar cells electrically connected in series in a conventional solar cell module.
[Explanation of symbols]
1, 11, 21 Solar cell
4, 14, 24 First lead electrode
5, 15, 25 Second lead electrode
6,16 Connection part

Claims (1)

A step of arranging the first solar cell and the second solar cell in a plane with a predetermined interval;
Attaching a first lead electrode on the upper surface of the first solar cell showing the first conductivity type;
Attaching a second lead electrode on the lower surface showing the second conductivity type of the second solar cell;
A method of manufacturing a solar cell module, comprising: a step of electrically connecting the first lead electrode and the second lead electrode at a connection portion located between the first solar cell and the second solar cell. Because
The second lead electrode protrudes from the lower surface of the second solar cell toward the first solar cell on the lower surface indicating the second conductivity type of the second solar cell, and the first solar cell and the second solar cell. 2 It is arranged in a straight line so as to be substantially parallel to the arrangement surface where the solar cells are arranged
The upper surface of the second lead electrode extending from the upper surface of the first solar cell toward the second solar cell and positioned between the first solar cell and the second solar cell. Bending in advance so as to be substantially parallel to the second lead electrode at the upper connection portion, and disposed on the upper surface showing the first conductivity type of the first solar cell,
In the connection portion, the first lead electrode and the second lead electrode are connected by soldering ,
The first solar cell and the second solar cell in a state where the first lead electrode and the second lead electrode are connected are sandwiched by a pair of planar members, and the pair of planar members, the first solar cell. And a space between the second solar cells is filled with a sealing material.

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