JP2010118705A - Solar battery module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problem: stress is added to fine wire electrodes since thermal expansion and thermal contraction to be generated in a wiring material are received by the fine wire electrodes. <P>SOLUTION: The wiring material 2 is connected to one principal plane of a solar battery 3 by resin adhesives, the solar battery 3 has: the plurality of fine wire electrodes 4 formed on the one principal plane; and an auxiliary electrode 4C formed so as to electrically connect the plurality of fine wire electrodes 4A, wherein a width of the auxiliary electrode 4C is formed so as to be equivalent to about 10 times width of each fine wire electrode 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a solar cell module having a plurality of solar cells electrically connected to each other by a wiring material.

  As shown in the conceptual cross-sectional view of FIG. 8, the solar cell module 11 includes a plurality of solar cells 31, 31... It is comprised by sealing with the sealing material 17 between.

  The solar cell 31 includes a photoelectric conversion unit having a photoelectric conversion function and a collecting electrode provided on a light receiving surface of the photoelectric conversion unit. The collector electrode was provided so as to extend in a direction perpendicular to the longitudinal direction of the plurality of line-shaped thin wire electrodes provided in parallel with each other over substantially the entire light incident surface of the photoelectric conversion unit. And a connection electrode. And the wiring material 2 is adhere | attached on the connection electrode with solder, and several adjacent solar cells 31, 31 ... are electrically connected (for example, refer patent document 1).

  Moreover, the temperature at the time of adhering the wiring material 2 can be lowered by using a resin adhesive containing conductive particles instead of solder as an adhesive for adhering the wiring material 2 to the electrode of the solar cell 31. (For example, refer patent document 2). Thus, by lowering the temperature at the time of bonding of the wiring material, it is possible to suppress the occurrence of warping, cracking and chipping of the solar cell due to the difference in the thermal expansion coefficient between the wiring material and the solar cell.

  By the way, in the connection using such a resin adhesive, the electrical connection between the wiring material and the electrode is performed only by the conductive particles in the resin adhesive. For this reason, it is expected that the resistance between the wiring material and the electrode is increased as compared with the case where the connection is made using solder. Therefore, the applicant of the present application has applied for a method for reducing such problems (see, for example, Patent Document 3). The connection method will be briefly described below with reference to the drawings.

  FIG. 9A is a plan view of the solar cell 31 to which the wiring member 2 is connected using this method as seen from the light receiving surface side, and FIG. 9B is a cross-sectional view taken along the line A-A in FIG. It is an expanded sectional view at the time of cut | disconnecting along. As shown in FIG. 9, in the solar cell 31, the thin wire electrodes 402 </ b> A are formed substantially parallel to each other on the photoelectric conversion unit 5, and no connection electrode is formed. The wiring member 2 includes a metal core member 2a such as copper and a conductor layer 2b such as solder formed on the surface. Then, as shown in FIG. 9B, the wiring material 2 and the fine wire electrode 402A are electrically connected by the tip of the fine wire electrode 402A being recessed into the conductor layer 2b. Further, the solar cell 31 and the wiring member 2 are mechanically connected by a resin adhesive 7.

  In this method, since the resin adhesive 7 is used for mechanical connection between the wiring member 2 and the solar cell 31, the temperature at the time of bonding can be reduced as compared with the connection using solder. For this reason, the curvature of the solar cell 31 by the heat added in the case of a connection can be reduced. Further, the electrical connection between the solar cell 31 and the wiring member 2 is performed by the fine wire electrode 402 </ b> A being embedded in the conductor layer 2 b of the wiring member 2. For this reason, electric resistance can be reduced compared with the connection through conductive materials, such as solder. Moreover, since it is not necessary to provide a connection electrode, the cost which concerns at the time of solar cell module creation can be reduced.

JP 2002-359388 A JP 2005-101519 A International Publication No. 2008/023795 Pamphlet

  By the way, in the method described above, the short direction of the fine wire electrode 402 </ b> A coincides with the long direction of the wiring member 2. For this reason, since thermal expansion / contraction generated in the longitudinal direction of the wiring member 402A is received in the short direction of the fine wire electrode 402A, it is expected that stress is applied to the fine wire electrode 402A.

  Therefore, an object of the present invention is to provide a solar cell module in which the stress applied to such a thin wire electrode is suppressed and the reliability is improved.

  A feature of the present invention is a solar cell module having a plurality of solar cells electrically connected to each other by a wiring material, wherein the wiring material is connected to one main surface of the solar cell by a resin adhesive, The solar cell has a plurality of fine wire electrodes formed on the one main surface, and an auxiliary electrode formed so as to electrically connect the plurality of fine wire electrodes, and the width of the auxiliary electrode is It is characterized by being formed so as to be about 10 times the width of the thin wire electrode.

  The auxiliary electrode is formed in a region to which the wiring material is connected.

  The wiring tab has a conductor layer on the surface, and at least one of the thin wire electrode and the auxiliary electrode has a portion that is recessed into the conductor layer.

  The peripheral portion of the auxiliary electrode is covered with the resin adhesive.

  The resin adhesive contains conductive particles.

  According to the present invention, a solar cell module with improved reliability and yield can be provided.

It is sectional drawing of the solar cell module which concerns on 1st Embodiment. It is a top view of the solar cell which concerns on 1st Embodiment. It is a top view explaining the connection relation of the solar cell and wiring material of the solar cell module which concerns on 1st Embodiment. It is sectional drawing explaining the connection relation of the solar cell and wiring material of the solar cell module which concerns on 1st Embodiment. It is a top view explaining the fine wire electrode which concerns on a modification. It is a top view of the solar cell which concerns on 2nd Embodiment. It is a top view explaining the connection relation of the solar cell and wiring material of the solar cell module which concerns on 2nd Embodiment. It is sectional drawing of the solar cell module which concerns on the past. It is a figure explaining the connection relation of the solar cell and wiring material of the solar cell module which concerns on the former.

Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.
<< First Embodiment >>
First, the solar cell module 1 which concerns on 1st Embodiment of this invention is demonstrated using FIGS. 1-4.

(Configuration of solar cell module)
FIG. 1 is a conceptual cross-sectional view showing the configuration of the solar cell module 1 according to the present embodiment. The solar cell module 1 has a plurality of solar cells 3, 3... Arranged along the arrangement direction Y, a wiring material 2, a light receiving surface protection member 15, a sealing material 17, and a back surface protection member 16. . Adjacent solar cells 3 and 3 are electrically connected by a wiring member 2 extending along the arrangement direction Y.

  On the light receiving surface side of the solar cell 3, a light receiving surface protection member 15 having a light transmitting property is adhered by a sealing material 17 having a light transmitting property. The light-receiving surface protection member 15 is configured using a light-transmitting material such as glass or light-transmitting plastic. Further, a back surface protection member 16 is bonded to the back surface side of the solar cell 3 with a sealing material 17. The back surface protection member 16 is made of, for example, a resin film such as PET or a laminated film having a structure in which an Al foil is sandwiched between resin films.

  The sealing material 17 is a resin having translucency such as EVA and PVB, and has a function of sealing the solar cell 3. Further, a terminal box for taking out electric power (not shown) is arranged on the back surface protection member 16, for example, on the back surface. Furthermore, a frame is attached to the outer periphery of the solar cell module as necessary.

  In manufacturing such a solar cell module 1, first, a light receiving surface protection member 15, a sealing material 17, a plurality of solar cells 3, a sealing material 17, and a back surface protection member 16 are sequentially stacked to form a laminate. To do. Next, it heats, applying a pressure from the upper and lower sides of a laminated body, and the solar cell module 1 is created.

(Solar cell structure)
FIG. 2A is a plan view of the solar cell 3 according to this embodiment as viewed from the light receiving surface side, and FIG. 2B is a plan view of the solar cell 3 as viewed from the back surface side. FIG. 2C is an enlarged view of a main part of a region surrounded by α in FIG. As shown in FIGS. 2A and 2B, the solar cell 3 includes a photoelectric conversion unit 5 and current collecting electrodes arranged on the light receiving surface and the back surface of the photoelectric conversion unit 5. ing. The photoelectric conversion unit 5 internally generates a photogenerated carrier by receiving light. The photogenerated carriers are electrons and holes generated in the photoelectric conversion unit 5 by receiving light.

  The photoelectric conversion unit 5 is made of a semiconductor material having a semiconductor junction such as a pn junction or a pin junction. Semiconductor materials include crystalline silicon semiconductors such as single crystal semiconductor silicon and polycrystalline silicon, compound semiconductors such as GaAs, amorphous silicon thin film semiconductors, compound thin film semiconductors, and other semiconductor materials made of known semiconductor materials. Can be used. As a material for forming a semiconductor junction with the semiconductor material, a crystalline semiconductor, an amorphous semiconductor, a compound semiconductor, or other known semiconductor materials can be used.

  As shown in the plan view of FIG. 2A, the current collecting electrode formed on the light receiving surface of the photoelectric conversion unit 5 has a plurality of fine wire electrodes 4A, 4A,. A plurality of thin wire electrodes 4A are arranged along the arrangement direction Y with the arrangement direction Y of the solar cells 3 as the short direction and the direction X substantially orthogonal to the arrangement direction Y as the long direction. A part of the fine wire electrode 4A also functions as a connection electrode for connecting the wiring member 2 as described later. The thin wire electrodes 4A, 4A,... Are electrodes for collecting electron / hole carriers generated in the photoelectric conversion unit 5 by light incidence. The thin wire electrodes 4A, 4A... Are arranged in parallel with each other over substantially the entire light receiving surface of the photoelectric conversion unit 5. The dimensions and number of the thin wire electrodes 4A are appropriately set in consideration of the dimensions and physical properties of the photoelectric conversion unit 5.

  As shown in FIG. 2A, the thin wire electrode 4A has a protruding portion 8 that protrudes toward the adjacent thin wire electrode 4A in a region to which the wiring member 2 is connected. In the same figure, the protrusion 8 has a mountain shape. At this time, as shown in FIG. 2C, the protruding portion 8 has an angle θ1 with respect to the arrangement direction Y, and is formed to protrude in the arrangement direction Y with a height A and a width B. Has been. And the protrusion part 8 is formed in the part which functions as a connection electrode for connecting the wiring material 2. FIG.

  FIG.2 (b) is the top view which looked at the solar cell from the back surface side. The collector electrode formed on the back surface also has a plurality of fine wire electrodes 41A, 41A,..., Like the collector electrode formed on the light receiving surface side. As shown in the figure, a plurality of the thin wire electrodes 41A are arranged along the arrangement direction Y, with the arrangement direction Y of the solar cells 3 as the short direction, the direction X substantially orthogonal to the arrangement direction Y as the long direction. Yes. A part of the thin wire electrode 41 </ b> A also functions as a connection electrode for connecting the wiring member 2. The thin wire electrodes 41A, 41A,... Are electrodes for collecting electron / hole carriers generated in the photoelectric conversion unit 5 by light incidence. The thin wire electrodes 41A, 41A,... Are arranged in parallel to each other over substantially the entire back surface of the photoelectric conversion unit 5.

  As shown in FIG. 2B, the fine wire electrode 41A has a protruding portion 8 that protrudes toward the adjacent fine wire electrode 41A in a region to which the wiring member 2 is connected. The dimensions and number of the fine wire electrodes 41A on the back side are appropriately set in consideration of the dimensions, physical properties, etc. of the photoelectric conversion unit 5. In addition, the current collecting electrode 41 on the back surface side can take various configurations without being limited thereto. For example, a conductive material may be formed on the entire back surface to form a current collecting electrode.

  Of the protrusions 8 formed on the light receiving surface and the back surface, the protrusion 81 on which the end of the wiring member 2 is arranged is preferably formed small so as not to protrude from the end of the wiring member 2. . In the present embodiment, the protrusions 8 formed on the light receiving surface and the back surface are formed so as to be opposite to each other when projected from the light receiving surface. Good. Moreover, although the protrusion direction of the protrusion part 8 is all formed in the same direction, you may form so that it may coexist. In the present embodiment, the protruding portion 8 is formed in all the regions corresponding to the wiring material 2 of the plurality of thin wire electrodes 4A and 41A, but may be formed only in a part. Further, the height A of the protruding portion 8 may be reduced on the fine wire electrodes 4A and 41A provided on the outermost side in the arrangement direction of the fine wire electrodes 4A and 41A so as not to protrude from the wiring material 2, The protrusion 8 may not be formed. In addition, the width B of the protruding portion is preferably set to a size that does not protrude from the wiring member 2.

  The collector electrodes 4 and 41 are formed from, for example, a thermosetting conductive paste using an epoxy resin as a binder and conductive particles as a filler. Moreover, in the case of a single crystal silicon solar cell, a polycrystalline silicon solar cell, etc., not limited to this, a fired paste composed of a metal powder such as silver or aluminum, a glass frit and an organic vehicle is used. Also good. Alternatively, a general metal material such as silver or aluminum may be used.

(Connection of wiring material)
FIG. 3A is a plan view seen from the light receiving surface side for explaining the connection relationship between the wiring member 2 and the fine wire electrode 4A. FIG. 3B is an enlarged view of a portion surrounded by the region β shown in FIG. 4 is an enlarged cross-sectional view taken along the line BB shown in FIG.

  As shown in FIGS. 3A and 3B, the wiring member 2 is disposed on the protruding portion 8 along the arrangement direction Y of the solar cells 3. Further, the protruding portion 8 protrudes along the arrangement direction Y.

  As shown in FIG. 4, the wiring member 2 is composed of a core member 2a such as copper and a conductor layer 2b such as solder formed on the surface. Then, the fine wire electrode 4A and the protruding portion 8 are recessed into the conductor layer 2b of the wiring material 2 so that the wiring material 2 and the fine wire electrode 4A are electrically connected. Further, the wiring member 2 and the solar cell 3 are mechanically connected by a resin adhesive 7. Further, as shown in FIG. 3B, the wiring member 2 and the solar cell 3 are bonded so that the peripheral portion of the protruding portion 8 is also covered with the resin adhesive 7. In addition, as shown to the figure, the resin adhesive material 7 may be divided | segmented by the adjacent fine wire electrode.

  Examples of the material of the resin adhesive 7 include an epoxy resin, an acrylic resin, a polyimide resin, a phenol resin, a urethane resin, a silicon resin, and the like. At least one selected from these, or a mixture of these resins, A polymer or the like can be applied. The resin adhesive 7 may have conductivity by applying metal particles selected from nickel, copper, silver, aluminum, tin, gold and the like, or may be insulating. In the case of the resin adhesive material 7 having conductivity, the wiring member 2 and the solar cell 3 may be electrically connected through the conductive particles.

(Function and effect)
According to the solar cell module 1 according to the present embodiment, the wiring member 2 is disposed on the protruding portion 8 provided so as to protrude toward the thin wire electrode 4A adjacent to a part of the thin wire electrode 4A, and the wiring member 2 2 is connected on the protrusion 8. At this time, since the longitudinal direction of the wiring member 2 is a direction along the arrangement direction Y, it is the same direction as the protruding direction of the protruding portion.

  The wiring material 2 expands and contracts due to heat even after the wiring material 2 and the solar cell 3 are bonded. At this time, the wiring member 2 expands and contracts more in the longitudinal direction (arrangement direction Y) than in the short direction of the wiring member 2. In such a case, conventionally, a force from the longitudinal direction (arrangement direction Y) due to expansion / contraction of the wiring material 2 is applied to the connection interface between the thin wire electrodes 4A and 41A and the wiring material 2 of the thin wire electrodes 4A and 41A. Join perpendicular to the short direction. Therefore, the force from the longitudinal direction (arrangement direction Y) of the wiring member 2 is applied to the connection portion between the thin wire electrodes 4A and 41A and the wiring member 2 with the magnitude of the force as it is, and stress is applied to the interface of the connection portion. I was concentrated.

  Therefore, in the present embodiment, a protruding portion 8 that protrudes in the longitudinal direction (arrangement direction Y) of the wiring material 2 is formed in a region to which the wiring material 2 of the thin wire electrode 4A is connected. At this time, the protrusion 8 is provided so as to have an angle θ1 with respect to the force applied in the longitudinal direction (arrangement direction Y) of the wiring member 2. Therefore, the force applied to the thin wire electrodes 4A and 41A from the arrangement direction Y is dispersed into a force in a direction along the mountain-shaped inclination of the protrusion 8 and a force in a direction perpendicular to the inclination. At this time, the force applied to the thin wire electrodes 4A and 41A is a force perpendicular to the inclination of the protruding portion. Therefore, compared with the case where the stress from the longitudinal direction (arrangement direction Y) of the wiring member 2 is directly applied to the thin wire electrodes 4A and 41A, the stress applied to the interface between the wiring member 2 and the thin wire electrodes 4A and 41A is caused by the protruding portions 8. Can be reduced. Therefore, the fall of the adhesive strength of the interface of the wiring material 2 and fine wire electrode 4A, 41A can be suppressed, and the reliability of the solar cell module 1 can be improved.

  Further, the wiring member 2 and the solar cell 3 are mechanically connected by the resin adhesive 7 and are bonded so that the peripheral portion of the protruding portion 8 is also covered by the resin adhesive 7. Therefore, since the adhesion area between the fine wire electrodes 4A and 41A and the resin adhesive 7 can be increased, a decrease in the adhesive strength can be suppressed and the reliability of the solar cell module 1 can be improved.

  Further, since the wiring member 2 is connected on the protruding portion 8, the bonding area of the wiring member 2 can be increased as compared with the case where the protruding portion 8 is not provided. Therefore, the adhesive strength between the wiring member 2 and the solar cell 3 can be increased, and the reliability of the solar cell module 1 can be increased.

  In the present embodiment, the protrusions 8 provided on the light receiving surface side and the back surface side are formed in the same direction, but may be formed in different directions within the same surface. Even in such a case, the stress generated by the expansion / contraction of the wiring member 2 can be reduced.

  In the present embodiment, the resin adhesive 7 is divided by the protruding portion 8. For this reason, the stress generated by the expansion / contraction of the resin adhesive 7 can be reduced.

  In the present embodiment, the thin wire electrode 4A and the wiring member 2 are electrically connected by being recessed into the conductor layer 2b of the wiring member 2. Therefore, electrical resistance can be reduced and the characteristics of the solar cell module can be improved as compared with the case where electrical connection is made through a conductive adhesive or the like.

(Modification)
In addition, in this embodiment, although the shape of the protrusion part 8 was formed in the mountain shape, it is not restricted to this, As shown in the enlarged plan view which shows the shape of the protrusion part 8 of FIG. Can take form. Moreover, as shown in FIG.5 (e), the top part of the protrusion part 8 does not need to be connected. Even in these cases, the protrusions 8 as shown in the figure are formed in the region to which the wiring member 2 is connected, so that the expansion and the expansion of the wiring member 2 and the solar cell 3 are the same as in the first embodiment. The stress generated by the shrinkage can be reduced, and the reliability of the solar cell module 1 can be increased.
<< Second Embodiment >>
A second embodiment of the present invention will be described with reference to FIGS. In the following description, descriptions of the same or similar parts as in the first embodiment are omitted.

  The difference between the present embodiment and the first embodiment is that an auxiliary electrode 4C is provided.

(Solar cell)
FIGS. 6A and 6B are plan views of the solar cell 3 according to the second embodiment as viewed from the light receiving surface side and the back surface side. FIG. 6C is an enlarged view of a portion surrounded by a region α2 shown in FIG.

  As shown in FIGS. 6A and 6B, the thin wire electrodes 4A and 41A, the auxiliary electrodes 4C, and the protruding portions 8 are formed on the light receiving surface and the back surface of the solar cell 3 as in the first embodiment. Has been. A plurality of thin wire electrodes 4A and 41A are arranged along the arrangement direction Y with the arrangement direction Y of the solar cells 3 as the short direction and the direction X substantially orthogonal to the arrangement direction Y as the long direction. As shown in the figure, the auxiliary electrodes 4C and 41C are formed so as to extend along the arrangement direction Y of the solar cells 3 so as to connect the tops of the projecting portions 8, and the auxiliary electrodes 4C and 41C and the thin wires The electrodes 4A and 41A are electrically connected. The widths of the auxiliary electrodes 4C and 41C are formed so as to be about 10 times as large as those of the thin wire electrodes 4A and 41A. The auxiliary electrodes 4C and 41C function as bus bar electrodes for collecting carriers collected by the thin wire electrodes 4A and 41A and also function as connection electrodes to which the wiring member 2 is connected.

  Further, as shown in FIG. 6C, the protruding portions 8 are formed so as to have an angle θ2 with respect to the arrangement direction Y as in the first embodiment.

(Connection of wiring material)
FIG. 7A is a plan view seen from the light receiving surface side in order to explain the connection relationship between the wiring member 2 and the fine wire electrode 4A. FIG. 7B is an enlarged view of a portion surrounded by a region β2 shown in FIG.

  As shown in FIGS. 7A and 7B, the wiring member 2 is arranged on the protruding portion 8 along the arrangement direction Y of the solar cells. Further, the protruding portion 8 protrudes in the direction along the arrangement direction Y.

  Further, as shown in the figure, the wiring member 2 is arranged on the auxiliary electrode 4C, and the wiring member 2 is arranged so that the longitudinal direction of the wiring member 2 extends along the arrangement direction Y of the solar cells 3. By arranging the wiring member 2 in this way, the longitudinal direction of the wiring member 2 is the same as the longitudinal direction of the auxiliary electrode 4C.

  In addition, as shown in FIG. 7B, the wiring member 2 and the solar cell 3 are mechanically connected by a resin adhesive 7. Then, at least one of the thin wire electrode 4A, the auxiliary electrode 4C, and the protruding portion 8 is indented into the conductor layer 2b of the wiring member 2 to make electrical connection. Further, as shown in the figure, the protruding portion 8 and the peripheral portion of the auxiliary electrode 4C are also covered and bonded by the resin adhesive 7.

(Function and effect)
In this embodiment, the same effect as that of the first embodiment can be obtained.

  Moreover, in this embodiment, since the wiring material 2 is connected also on the protrusion part 8 and auxiliary electrode 4C, 41C, adhesive strength can be raised.

  In addition, auxiliary electrodes 4C and 41C are formed extending along the arrangement direction Y so as to connect the tops of the protrusions 8. The wiring member 2 is also connected to the auxiliary electrodes 4C and 41C. Therefore, the thin wire electrodes 4A and 41A and the wiring member 2 can be reliably connected, and the reliability of the solar cell module can be improved.

Further, the auxiliary electrodes 4C and 41C are formed so as to be about 10 times as large as the thin wire electrodes 4A and 41A. Therefore, the auxiliary electrodes 4C and 41C are prevented from protruding due to misalignment during wiring.
(Example)
Hereinafter, the solar cell module according to the present invention will be specifically described with reference to examples.

  As an example of the present invention, a solar cell module according to the first embodiment was produced as follows. In the following manufacturing method, a process is divided into steps 1 to 5 and described.

<Step 1> Formation of Photoelectric Conversion Part First, an n-type single crystal silicon substrate of about 125 mm square having a resistivity of about 1 Ω · cm and a thickness of about 200 μm was prepared. Next, an CVD method is used to form an i-type amorphous silicon layer having a thickness of about 5 nm and a p-type amorphous silicon layer having a thickness of about 5 nm on the light-receiving surface of the n-type single crystal silicon substrate. Were formed in this order.

  Next, an i-type amorphous silicon layer having a thickness of about 5 nm and an n-type amorphous silicon layer having a thickness of about 5 nm are formed on the back surface of the n-type single crystal silicon substrate by CVD. Formed in order.

  Next, an ITO film having a thickness of about 100 nm was formed on each of the p-type amorphous silicon layer and the n-type amorphous silicon layer by sputtering.

  The photoelectric conversion part of the solar cell which concerns on an Example was produced according to the above process.

<Process 2> Current collection electrode formation Next, the surface of the ITO film | membrane distribute | arranged to the light-receiving surface side and back surface side of a photoelectric conversion part was screen-printed using the epoxy-type thermosetting silver paste by a printing method, respectively. A current collecting electrode having the following shape was formed by the method.

  For the samples of Examples 1 to 5 according to the first embodiment, a plurality of thin wire electrodes 4A and 41A having a width of about 100 μm and a thickness of about 40 μm were formed at a pitch of about 2 mm. In addition, the protrusion 8 has the width B of 2 mm and the samples of Examples 1, 2, 3, 4, and 5 so that the angle θ1 of the protrusion 8 with respect to the arrangement direction Y is 15, 30, 45, 60, and 75 degrees. Each formed.

<Process 3> Wiring material connection process Next, the resin adhesive which contains a thermosetting epoxy resin by the dispenser etc. in the predetermined location of the protrusion part 8 vicinity of the light-receiving surface side and back surface side of the sample of Examples 1-5. Was applied. Next, a wiring material in which the core material made of copper was covered with a conductor layer made of solder was placed on the resin adhesive applied to each sample.

And the wiring material 2 distribute | arranged on the solar cell was pinched | interposed one by one by the heating part from the upper and lower sides, it heated, applying a predetermined pressure, and the wiring material 2 and the solar cells 3, 3, ... were connected. Moreover, about the sample of Examples 1-5, the pressure was adjusted so that the processus | protrusion of a connection electrode might sunk in the conductor layer formed in the wiring material surface. Each pressure was obtained in advance by a preliminary experiment.
(Comparative example)
A sample of Comparative Example 1 was prepared in the same manner as the samples of Examples 1 to 5 except that no protrusion was formed.
(result)
About the solar cell module which concerns on Examples 1-5 and the comparative example 1, the temperature cycle test (JIS C8917) was done in the period of 3 times. And the deterioration rate of the output of the solar cell module which generate | occur | produced by the temperature cycle test was computed from the conversion efficiency before a test and the conversion efficiency after a test, as shown in Formula 1.

  Table 1 shows the results of the solar cell modules according to Examples 1 to 5 and Comparative Example 1.

  From Table 1, it can be seen that the deterioration rate of Examples 1 to 5 was improved with respect to Comparative Example 1. From these results, in the samples of Examples 1 to 5, the protrusions are formed so as to have an angle θ1 with respect to the arrangement direction Y of the solar cells in the region where the wiring material on the thin wire electrode is connected. It is considered that the stress applied toward the arrangement direction Y of the solar cells was reduced by the thermal expansion / contraction of the material. Therefore, since the reduction | decrease of the adhesive strength in the interface of a wiring material and a fine wire electrode was suppressed, it is thought that the deterioration rate of the solar cell module was improved.

DESCRIPTION OF SYMBOLS 1 Solar cell module 2 Wiring material 2a Core material 2b Conductor layer 3 Solar cell 4A, 41A Fine wire electrode 4C, 41C Auxiliary electrode 5 Photoelectric conversion part 7 Resin adhesive material 8 Protrusion part

Claims (5)

A solar cell module having a plurality of solar cells electrically connected to each other by a wiring material,
The wiring material is connected to one main surface of the solar cell by a resin adhesive,
The solar cell has a plurality of thin wire electrodes formed on the one main surface, and an auxiliary electrode formed so as to electrically connect the plurality of thin wire electrodes,
A solar cell module, wherein the auxiliary electrode is formed to have a width equal to or about 10 times the width of the thin wire electrode.   The solar cell module according to claim 1, wherein the auxiliary electrode is formed in a region to which the wiring material is connected. The wiring tab has a conductor layer on the surface,
2. The solar cell module according to claim 1, wherein at least one of the fine wire electrode and the auxiliary electrode has a portion that is recessed into the conductor layer.   The solar cell module according to any one of claims 1 to 3, wherein a peripheral portion of the auxiliary electrode is covered with the resin adhesive.   The solar cell module according to claim 1, wherein the resin adhesive contains conductive particles.

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