Abstract:
This solar module has: a base member that is curved in the vertical direction and the horizontal direction; strings each constituted from a plurality of solar cells and first wiring members connecting adjacent solar cells in the vertical direction, wherein a plurality of the strings are arranged side by side on the base member; and a string group constituted from a plurality of the strings and second wiring members, which are disposed at both sides in the vertical direction of the strings and connected to the first wiring members, thereby connecting adjacent strings to one another in the horizontal direction. The string group is divided into at least two blocks that are side by side in the vertical direction. Second wiring members are disposed adjacent in the horizontal direction, or second wiring members are disposed adjacent in the vertical direction between the blocks, and are secured to one another.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a continuation under 35 U.S.C. §120 of PCT/JP2015/004264, filed Aug. 25, 2015, which is incorporated herein by reference and which claimed priority to Japanese Patent Application No. 2014-174185 filed on Aug. 28, 2014. The present application likewise claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2014-174185 filed on Aug. 28, 2014, the entire content of which is also incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to a solar cell module and a method of manufacturing a solar cell module. 
       BACKGROUND 
       [0003]    A solar cell module is known in which a group of strings of solar cells are placed over a substrate having a three-dimensional curvature (hereinafter referred to as “curved substrate”) (for example, refer to Patent Literature 1). As described in Patent Literature 1, a solar cell module which is three-dimensionally curved is desirably manufactured, from the viewpoint of productivity or the like, by placing the group of strings over the curved substrate after the group of strings have been manufactured on a flat surface. 
       CITATION LIST 
     Patent Literature 
       [0004]    Patent Literature 1: JP 2014-96511 A 
       SUMMARY 
       [0005]    When the group of strings are placed over the curved substrate, there is a possibility, for example, that a spacing between strings will be narrowed at some of the group of strings, the solar cells will contact each other, and consequently, short-circuiting, cell cracking or the like will occur. In addition, in the group of strings placed over the curved substrate, because a large load tends to be applied on a wiring member, it is desired to reduce the load and to thereby improve the reliability. 
         [0006]    According to one aspect of the present disclosure, there is provided a solar cell module comprising: a substrate which is curved in a longitudinal direction and in a lateral direction; a plurality of strings each comprising a plurality of solar cells and first wiring members that connect adjacent solar cells to each other in the longitudinal direction, and placed over the substrate, aligned in the lateral direction; and a group of strings comprising a plurality of the strings and second wiring members that are placed on sides of the string in the longitudinal direction, that are connected to the first wiring members, and that connect adjacent strings to each other in the lateral direction, wherein the group of strings is divided into at least two blocks aligned in the longitudinal direction, and at least two of the second wiring members of the strings placed adjacent to each other in the lateral direction are fixed to each other and/or at least two of the second wiring members placed adjacent to each other in the longitudinal direction between the blocks are fixed to each other. 
         [0007]    According to another aspect of the present disclosure, there is provided a method of manufacturing a solar cell module, comprising: connecting adjacent solar cells to each other in a longitudinal direction with first wiring members to form a plurality of strings in each of which a plurality of solar cells are arranged in one line; placing second wiring members on sides of the string in the longitudinal direction and connecting the second wiring members to the first wiring members, to connect adjacent strings in a lateral direction and to form a group of strings which is divided into at least two blocks aligned in the longitudinal direction; and after fixing to each other at least two of the second wiring members of the strings placed adjacent to each other in the lateral direction and/or at least two of the second wiring members placed adjacent to each other in the longitudinal direction between the blocks, placing the group of strings over a substrate which is curved in the longitudinal direction and in the lateral direction, or, after placing the group of strings over the substrate which is curved in the longitudinal direction and in the lateral direction, fixing to each other at least two of the second wiring members of the strings placed adjacent to each other in the lateral direction and/or at least two of the second wiring members placed adjacent to each other in the longitudinal direction between the blocks. 
         [0008]    According to an aspect of the present disclosure, in a solar cell module which is three-dimensionally curved, a superior arrangement state of the solar cells can be obtained without occurrence of short-circuiting, cell cracking, or the like due to contact of the solar cells. In addition, load applied to the wiring member can be reduced and the reliability can be consequently improved. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0009]      FIG. 1  is a perspective diagram of a solar cell module according to a first embodiment of the present disclosure, viewed from a light receiving surface side (also showing a cross section in the lateral direction of the solar cell module). 
           [0010]      FIG. 2  is a plan view of the solar cell module according to the first embodiment of the present disclosure, viewed from the light receiving surface side. 
           [0011]      FIG. 3  is a diagram showing a part of a cross section, in a longitudinal direction, of the solar cell module according to the first embodiment of the present disclosure. 
           [0012]      FIG. 4  is a diagram for explaining a method of manufacturing the solar cell module according to the first embodiment of the present disclosure. 
           [0013]      FIG. 5  is a plan view of a solar cell module according to a second embodiment of the present disclosure, viewed from a light receiving surface side. 
           [0014]      FIG. 6  is a diagram for explaining a method of manufacturing the solar cell module according to the second embodiment of the present disclosure. 
           [0015]      FIG. 7  is a plan view of a solar cell module according to a third embodiment of the present disclosure, viewed from the light receiving surface side. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0016]    Examples of embodiments of the present disclosure will now be described in detail with reference to the drawings. 
         [0017]    The drawings referred to in the embodiments are schematically drawn, and the size, ratio, or the like of the constituting elements shown in the drawings may differ from the actual structure. The specific size, ratio, or the like should be determined in consideration of the following description. 
         [0018]    In the present specification, a term “longitudinal direction” and a term “lateral direction” are used as terms indicating directions. The longitudinal direction refers to a direction along which a plurality of blocks of a group of string are arranged. The lateral direction refers to a direction orthogonal to the longitudinal direction, and is a direction along which the strings of the group of strings are arranged. Further, a description of “providing a second member over a first member” is not intended to mean only the case where the first and second members are provided in direct contact with each other, unless otherwise specified. That is, such a description includes a case where another member exists between the first and second members. 
         [0019]    In the following, a surface in a solar cell module where the solar light is primarily incident (exceeding 50% and up to 100%) is referred to as a “light receiving surface”, and a surface opposite to the light receiving surface is referred to as a “back surface”. The terms light receiving surface and back surface are also used for constituent elements of the solar cell or the like. 
       First Embodiment 
       [0020]    A solar cell module  10  according to a first embodiment of the present disclosure will now be described in detail with reference to  FIGS. 1 ˜ 4 .  FIG. 1  and  FIG. 2  are respectively a perspective view and a plan view of the solar cell module  10 , viewed from a light receiving surface side.  FIG. 3  is a diagram showing a part of a cross section in a longitudinal direction of the solar cell module  10 . 
         [0021]    As shown in  FIGS. 1 ˜ 3 , the solar cell module  10  comprises a plurality of solar cells  11 , a first protection component  12  provided on a side of a light receiving surface of the solar cell  11 , and a second protection component  13  provided on a side of a back surface of the solar cell  11 . The plurality of solar cells  11  are sandwiched and held between the first protection component  12  and the second protection component  13 , and are sealed by an encapsulant  14  (refer to  FIG. 3 ) filled between the protection components. 
         [0022]    The solar cell module  10  comprises a substrate which is curved in a longitudinal direction and in a lateral direction, and has a three-dimensionally curved shape. In the present embodiment, the first protection component  12  is the substrate which is curved in the longitudinal direction and in the lateral direction and which has a three-dimensional curvature. As will be described later in detail, the second protection component  13 , the encapsulant  14 , and a group of strings  30  (refer to  FIGS. 1 and 2 ) are placed over the first protection component  12 , to obtain the solar cell module  10  which is three-dimensionally curved. 
         [0023]    The solar cell module  10  has strings  20  (refer to  FIGS. 1 and 2 ) in each of which a plurality of the solar cells  11  are arranged in one line. The string  20  comprises a plurality of solar cells  11 , and first wiring members  21  that connect adjacent solar cells  11  to each other in the longitudinal direction. A plurality of the strings  20  are placed over the first protection component  12 , aligned in the lateral direction. The first wiring member  21  is bent, for example, in a thickness direction of the module in a region between adjacent solar cells  11 , and is attached using an adhesive or the like to an electrode on the light receiving surface side of one solar cell  11  and to an electrode on the back surface side of the other solar cell  11  (refer to  FIG. 3 ). 
         [0024]    The solar cell module  10  comprises a group of strings  30  in which a plurality of the strings  20  are aligned in the lateral direction. The group of strings  30  comprises a plurality of the strings  20 , and second wiring members  31  that are placed on sides of the string  20  in the longitudinal direction, that are connected to the first wiring members  21 , and that connect adjacent strings  20  to each other in the lateral direction. Some of the second wiring members  31  are connected to a terminal portion (not shown) provided on the back side of the second protection component  13 , for example. 
         [0025]    In the present embodiment, the group of strings  30  is divided into two blocks  30 A and  30 B aligned in the longitudinal direction, with  6  rows of strings  20  in each block, and a total of  12  rows of strings  20 . In the following, the strings  20  of the block  30 A are referred to, from the left of  FIG. 2 , as strings  20 Aa,  20 Ab,  20 Ac,  20 Ad,  20 Ae, and  20 Af. Similarly, the strings  20  of the block  30 B are referred to as strings  20 Ba,  20 Bb,  20 Bc,  20 Bd,  20 Be, and  20 Bf. The  6  rows of strings  20  of the block  30 A and the  6  rows of the string  20  of the block  30 B are placed in an aligned manner in the longitudinal direction. For example, the strings  20 Aa and  20 Ba are aligned in the longitudinal direction. 
         [0026]    The solar cell  11  comprises a photoelectric conversion unit which produces carriers upon receiving solar light. The photoelectric conversion unit has, as electrodes for collecting the produced carriers, a light receiving surface electrode formed over the light receiving surface of the photoelectric conversion unit and a back surface electrode formed over the back surface, for example (both of which are not shown in the figures). The wiring members  21  are connected to the electrodes. However, the structure of the solar cell  11  is not limited to this structure, and the structure may be, for example, a structure in which the electrode is formed only over the back surface of the photoelectric conversion unit. Desirably, the back surface electrode is formed in a larger area than the light receiving surface electrode, and a surface having a larger electrode area (or a surface on which the electrodes are formed) may be considered as the back surface of the solar cell  11 . 
         [0027]    The photoelectric conversion unit comprises a semiconductor substrate made of, for example, crystalline silicon (c-Si), gallium arsenide (GaAs), indium phosphide (InP), or the like, an amorphous semiconductor layer formed over the semiconductor substrate; and a transparent conductive layer formed over the amorphous semiconductor layer. As a specific example, a structure may be employed in which an i-type amorphous silicon layer, a p-type amorphous silicon layer, and a transparent conductive layer are sequentially formed over one surface of an n-type monocrystalline silicon substrate, and an i-type amorphous silicon layer, an n-type amorphous silicon layer, and a transparent conductive layer are sequentially formed over the other surface. The transparent conductive layer is desirably formed from a transparent conductive oxide in which a metal oxide such as indium oxide (In 2 O 3 ) and zinc oxide (ZnO) is doped with Sn, Sb, or the like. 
         [0028]    For the first protection component  12  and the second protection component  13 , for example, a glass substrate, a resin substrate, a resin film, or the like may be employed. For the first protection component  12 , a member having a light transmissive characteristic is used, and from the viewpoint of heat resistivity and endurance, a glass substrate is desirably used. A thickness of the glass substrate is, for example, about 2˜6 mm. For the second protection component  13 , a transparent member may be used or a non-transparent member may be used. For the second protection component  13 , for example, a resin film is used. A thickness of the resin film is, for example, about 50 300 μm. 
         [0029]    In the present embodiment, as described above, as the substrate which is curved in the longitudinal direction and in the lateral direction, the first protection component  12  is used. The first protection component  12  is not particularly limited so long as the component has a curved surface which is curved in the longitudinal direction and in the lateral direction, and has, for example, a curved surface with a three-dimensional curvature such as part of a spherical surface. The curvature of the first protection component  12  is not particularly limited, and may be a constant over the entire region of the first protection component  12  or different at a part of the regions. In the following, a structure is described in which the curvature of the first protection component  12  is approximately constant. The first protection component  12  is, for example, a transparent glass substrate which is three-dimensionally curved with an approximately constant curvature, and has an approximately rectangular shape in the plan view. In the present specification “approximately” is intended to include, for example, in the case of “approximately constant”, cases of completely constant and also cases of substantially constant. 
         [0030]    The encapsulant  14  has a function to fill a gap between the solar cell  11  and the protection components, to seal the solar cell  11 . The encapsulant  14  desirably has, as a primary constituent, a resin that can be applied in a lamination process to be described below. As the resin, ethylene vinyl acetate copolymer (EVA), polyvinylbutyral (PVB), or the like can be exemplified. The encapsulant  14  may include various additives such as an oxidation prevention agent, a flame resisting agent, an ultraviolet absorption agent, or the like, and the encapsulant  14  placed at the back surface side of the solar cell  11  may contain pigments such as titanium oxide. 
         [0031]    As shown in  FIGS. 1 and 2 , the group of strings  30  is divided into at least two blocks aligned in the longitudinal direction. At least two of the second wiring members  31  of the strings  20  placed adjacent to each other in the lateral direction are fixed to each other and/or at least two of the second wiring members  31  placed adjacent to each other in the longitudinal direction between the blocks are fixed to each other. 
         [0032]    The group of strings  30  is desirably divided into two blocks  30 A and  30 B. In the present embodiment, the group of strings  30  is divided into two at a central portion in the longitudinal direction, and numbers of solar cells  11  forming the strings  20  of the blocks  30 A and  30 B are equal to each other (four in the example configuration shown in  FIG. 2 ). As the number of cells in the string  20  is increased, that is, as the string  20  becomes longer, the placement becomes more easily disturbed. Thus, in the solar cell module  10 , the string  20  is shortened by the division of the group of strings  30 , to suppress the disturbance in the placement of the strings  20 . A length of the string  20  in each block may be suitably changed according to the curvature of the substrate or the like, and may be set, for example, to be shorter as the curvature of the substrate becomes larger. 
         [0033]    Second wiring members  31  are prefeably provided on both sides in the longitudinal directions of the blocks  30 A and  30 B,. In the present embodiment, a plurality of second wiring members  31 A are placed on the sides of the block  30 A in the longitudinal direction, and a plurality of second wiring members  31 B are placed on the sides of the block  30 B in the longitudinal direction. In a region between the blocks  30 A and  30 B (boundary position), the second wiring members  31 A and  31 B are placed adjacent to each other in the longitudinal direction. In addition, the blocks  30 A and  30 B are electrically connected to each other by, for example, a cable provided on the back side of the second protection component  13 , or the like. 
         [0034]    The string  20  is desirably formed by connecting two adjacent solar cells  11  by a plurality (for example, three) of first wiring members  21  aligned in the lateral direction. The plurality of first wiring members  21  extend from regions above solar cells  11  positioned at the ends of the row of each string  20  in the sides in the longitudinal direction, and are connected to the second wiring members  31 . 
         [0035]    In the example configuration shown in  FIG. 2 , four second wiring members  31 A are placed adjacent in the lateral direction to a side of one end of the block  30 A in the longitudinal direction (opposite side from the block  30 B), and two of the four second wiring members  31 A connect two adjacent strings  20  (the block  30 B has a similar structure). Specifically, strings  20 Ab and  20 Ac, and strings  20 Ad and  20 Ae are connected to each other by second wiring members  31 A placed at the side of the one end of the block  30 A in the longitudinal direction. The remaining two second wiring members  31 A are connected only to the strings  20 Aa and  20 Af, respectively. For example, the four second wiring members  31 A are connected to the terminal portion. 
         [0036]    On the side of the other end of the block  30 A in the longitudinal direction (on the side of the block  30 B), three second wiring members  31 A are placed adjacent to each other in the lateral direction, and the wiring members connect two adjacent strings  20 . Specifically, the strings  20 Aa and  20 Ab, the strings  20 Ac and  20 Ad, and the strings  20 Ae and  20 Af are connected to each other respectively by the second wiring members  31 A placed at the side of the one end of the block  30 A in the longitudinal direction. 
         [0037]    In the group of strings  30 , the second wiring members  31 A placed adjacent to each other in the lateral direction and the second wiring members  31 B placed adjacent to each other in the lateral direction are respectively fixed to each other. Desirably, two adjacent second wiring members  31 A are fixed to each other only at the side of the one end of the block  30 A in the longitudinal direction, and the second wiring members  31 A placed at the side of the other end of the block  30 A in the lateral direction are not fixed to each other (the structure is similar for the block  30 B). In other words, preferably, the second wiring members  31  placed adjacent to each other in the lateral direction are fixed to each other at both sides in the longitudinal direction of the group of strings  30 . For the fixation of the second wiring members  31 A and  31 B, for example, an adhesion tape  32  is used. In the present embodiment, the adhesion tape  32  is provided respectively over two second wiring members  31 A placed adjacent to each other in the lateral direction, between the strings  20 Aa and  20 Ab, between the strings  20 Ac and  20 Ad, and between the strings  20 Ae and  20 Af. 
         [0038]    The second wiring members  31  are desirably fixed by the adhesion tape  32  as described above. A material of the adhesion tape  32  is not particularly limited so long as the material has an insulating characteristic and has a superior contact characteristic with the second wiring member  31 . The adhesion tape  32  is desirably thinner than a thickness of the second wiring member  31 , and is adhered to one surface or both surfaces of the second wiring member  31 . For fixation of the second wiring members  31  to each other, an adhesive, a clip, or the like may alternatively be used, but from the viewpoint of the productivity and design, the use of the adhesion tape  32  is desirable. 
         [0039]    The second wiring members  31 A and  31 B fixed by the adhesion tape  32  are desirably placed along the curved surface of the first protection component  12 , for example, along a virtual curve α having a constant curvature along the curved surface of the first protection component  12 . With such a configuration, for example, distortions of the second wiring members  31 A and  31 B can be reduced, and the load applied thereto can be reduced. In addition, with the fixation of the second wiring members  31 A and  31 B, movement of the string  20  can be constrained for a certain degree, and disturbance of the placement of the string  20  when the group of strings  30  is placed over the first protection component  12  can be suppressed. When the second wiring members  31 A and  31 B are placed along the virtual curve α, the string  20 , in particular, the string  20  positioned on the sides of the group of strings  30  in the lateral direction, tends to more easily move toward the inner side. However, with the division of the group of strings  30 , the effect of the movement can be suppressed. In other words, the narrowing of spacing between the strings  20  at a part thereof and consequent contact of the solar cells  11  can be prevented. 
         [0040]    A length of the group of strings  30  in the longitudinal direction is desirably set longer from the ends in the lateral direction toward the central portion in the lateral direction. In the present embodiment, of the strings  20  of the block  30 A, the strings  20 Ac and  20 Ad placed at the central portion of the block in the lateral direction protrudes the most on the side of one end in the longitudinal direction. The degree of protrusion of the string  20  becomes larger from the ends of the block  30 A in the lateral direction toward the central portion in the lateral direction. Meanwhile, in the block  30 B, the strings  20 Bc and  20 Bd placed at the central portion in the lateral direction protrude the most toward the side of the other end in the longitudinal direction, and the degree of protrusion of the strings  20  becomes larger from the ends in the lateral direction toward the central portion in the lateral direction. 
         [0041]    In other words, the strings  20  of the blocks  30 A and  30 B aligned in the longitudinal direction are placed to become further away from each other from the ends of the group of strings  30  in the lateral direction toward the central portion in the lateral direction. The spacing between the adjacent blocks  30 A and  30 B becomes maximum at the central portion of the group of strings  30  in the lateral direction, for example, between the strings  20 Ac and  20 Ad and the strings  20 Bc and  20 Bd. 
         [0042]    The solar cell module  10  having the above-described structure can be manufactured by laminating the group of strings  30  using resin sheets forming the first protection component  12 , the second protection component  13 , and the encapsulant  14 . In a laminating device, the first protection component  12 , a first resin sheet forming the encapsulant  14 , the group of strings  30 , a second resin sheet forming the encapsulant  14 , and the second protection component  13  are layered in sequence over a heater. From the viewpoint of productivity or the like, the group of strings  30  is placed over the first protection component  12  after being manufactured on a flat surface, as will be described later. The layered structure is heated, for example, to a temperature at which the resin sheet forming the encapsulant  14  is softened under a vacuum state. Then, the heating is continued while the constituent members are pressed toward the heater side under an atmospheric pressure, to laminate the members, and to consequently obtain the solar cell module  10 . 
         [0043]      FIG. 4  shows the group of strings  30  manufactured on a flat surface (and before being placed over the substrate). 
         [0044]    As shown in  FIG. 4 , the group of strings  30  is manufactured by forming the string  20  on a flat surface by connecting adjacent solar cells  11  in the longitudinal direction with the first wiring members  21 , and connecting the second wiring member  31  to the first wiring member  21  of each string. In the present embodiment, the second wiring members  31  are placed on the sides of the string  20  in the longitudinal direction to connect adjacent strings  20  in the lateral direction and to form the group of strings  30  divided into two blocks  30 A and  30 B aligned in the longitudinal direction. In this case, the second wiring members  31 A and  31 B extend straight in the lateral direction, and the spacing between the locks  30 A and  30 B is approximately constant. 
         [0045]    Next, at least the second wiring members  31  placed adjacent to each other in the lateral direction or the second wiring members  31  placed adjacent to each other in the longitudinal direction between the blocks are fixed to each other using, for example the adhesion tape  32 . In the present embodiment, the adhesion tape  32  is adhered over two adjacent second wiring members  31 A only at one end side of the block  30 A in the longitudinal direction, to fix the wiring members. In the block  30 B, the adhesion tape  32  is adhered over two adjacent second wiring members  31 B only at the other end side in the longitudinal direction. 
         [0046]    Next, the group of strings  30  to which the adhesion tape  32  is adhered is placed over the first protection component  12 , and is laminated along with the constituting members. When the group of strings  30  is placed over the first protection component  12 , the second wiring member  31  fixed by the adhesion tape  32  is placed along the curved surface of the first protection component  12 , and a length of the group of strings  30  in the longitudinal direction becomes longer from the ends in the lateral direction toward the central portion in the lateral direction. In this manner, the solar cell module  10  having the above-described structure is obtained. Alternatively, the second wiring members  31  may be fixed by the adhesion tape  32  after the group of strings  30  has been placed over the first protection component  12 . 
         [0047]    As described, in the solar cell module  10 , the second wiring members  31  are fixed by the adhesion tape  32 , and the group of strings  30  is divided into the blocks  30 A and  30 B. 
         [0048]    With this configuration, it is possible to suppress disturbance in the placement of the strings  20  when the group of strings  30  is placed over the first protection component  12 , and to prevent occurrence of short-circuiting, cell cracking, or the like due to contact of solar cells  11 . Further, in addition to the reduction of the load on the second wiring member  31 , the load applied on the first wiring member  21  can also be reduced, and, for example, a superior outer appearance (superior arrangement state of the solar cells  11 ) and a high reliability can be achieved. 
       Second Embodiment 
       [0049]    A solar cell module  50  according to a second embodiment of the present disclosure will now be described in detail with reference to  FIGS. 5 and 6 . In the following, constituent elements similar to those in the above-described embodiment are assigned the same reference numerals and will not be described again. 
         [0050]      FIG. 5  is a plan view of the solar cell module  50  viewed from a light receiving surface side. 
         [0051]    As shown in  FIG. 5 , the solar cell module  50  differs from the solar cell module  10  in that the second wiring members  31 A and  31 B placed adjacent to each other in the longitudinal direction between blocks  51 A and  51 B are fixed to each other. Further, the solar cell module  50  differs from the solar cell module  10  in that the second wiring members  31 A placed adjacent to each other in the lateral direction and the second wiring members  31 B placed adjacent to each other in the lateral direction are not connected. The second wiring members  31 A and the second wiring members  31 B are desirably fixed using the adhesion tape  32 , similar to the solar cell module  10 . 
         [0052]    In the present embodiment, the strings  20  of each block are connected in the longitudinal direction via the second wiring members  31 A and  31 B and the adhesion tape  32  to form a pair of two rows of strings. For example, the second wiring member  31 A connecting the strings  20 Aa and  20 Ab and the second wiring member  31 B connecting the strings  20 Ba and  20 Bb are fixed to each other using the adhesion tape  32 . 
         [0053]    A length of a group of strings  51  in the lateral direction desirably becomes longer from ends in the longitudinal direction toward a boundary position between the blocks  51 A and  51 B. In the present embodiment, the group of strings  51  is divided into two at the central portion in the longitudinal direction, and the numbers of solar cells  11  in the strings  20  of the blocks  51 A and  51 B are identical to each other. In other words, in the group of strings  51 , the central portion in the longitudinal direction protrudes on both sides in the lateral direction, and the length in the lateral direction becomes longer from the ends in the longitudinal direction toward the central portion in the longitudinal direction. 
         [0054]    The strings  20  placed on the sides of the group of strings  51  in the lateral direction are placed along a virtual curve β having a constant curvature along the curved surface of the first protection component  12 . That is, on the sides of the group of strings  51  in the lateral direction, the strings  20  are formed in such a manner that the strings protrude on sides opposite to each other. 
         [0055]    The group of strings  51  is formed such that a gap (spacing) between the adjacent strings  20  is widened from ends of the group of strings  51  in the longitudinal direction toward the boundary position of each block (central portion of the group of strings  51  in the longitudinal direction). More specifically, the spacing between the pairs of the strings connected in the longitudinal direction via the second wiring members  31 A and  31 B and the adhesion tape  32  becomes widened toward the central portion of the group of strings  51  in the longitudinal direction. 
         [0056]      FIG. 6  shows the group of strings  51  manufactured on a flat surface (before being placed over the substrate). 
         [0057]    As shown in  FIG. 6 , similar to the case of the solar cell module  10 , the group of strings  51  is desirably manufactured on a flat surface, and the strings  20  extend straight in the longitudinal direction before being placed over the first protection component  12 . In the present embodiment, the second wiring members  31 A and  31 B placed adjacent to each other in the longitudinal direction between the blocks are fixed using the adhesion tape  32 . 
         [0058]    The group of strings  51  to which the adhesion tape  32  is adhered is placed over the first protection component  12 , and is laminated with the constituting members, so that the solar cell module  50  having the above-described structure is obtained. In the case of the present embodiment, when the group of strings  51  is placed over the first protection component  12 , the strings  20  positioned on the sides of the group of strings  51  in the lateral direction are placed along the curved surface of the first protection component  12 , and the central portion of the group of strings  51  in the longitudinal direction protrudes on the sides in the lateral direction. In this case, the solar cells  11  positioned near the ends of the rows of the strings  20  becomes easier to move toward the inner side, but, with the division of the group of strings  51 , the effect of such a movement is suppressed, and contact of the solar cells  11  can be prevented. 
       Third Embodiment 
       [0059]    A solar cell module  70  according to a third embodiment of the present disclosure will now be described in detail with reference to  FIG. 7 . In the following, constituent elements similar to those of the above-described embodiments will be assigned the same reference numerals and will not be repeatedly described. 
         [0060]      FIG. 7  is a plan view of the solar cell module  70  viewed from a light receiving surface side. 
         [0061]    As shown in  FIG. 7 , the solar cell module  70  differs from the solar cell modules  10  and  50  in that the second wiring members  31 A placed adjacent to each other in the lateral direction are fixed, the second wiring members  31 B placed adjacent to each other in the lateral direction are fixed, and the second wiring members  31 A and  31 B placed adjacent to each other in the longitudinal direction are fixed to each other. In this case also, the second wiring members  31  are desirably fixed using the adhesion tape  32 . 
         [0062]    In the solar cell module  70 , for example, a length of a group of strings  71  in the longitudinal direction becomes longer from the ends in the lateral direction toward the central portion in the lateral direction, and a length in the lateral direction becomes longer from the ends in the longitudinal direction toward a boundary position between blocks  71 A and  71 B. In other words, in the group of strings  71 , the central portion in the lateral direction protrudes to sides in the longitudinal direction and the central portion in the longitudinal direction protrudes to the side in the lateral direction. The degree of protrusion, however, is smaller compared to the cases of, for example, the groups of strings  30  and  50 . 
         [0063]    In the solar cell module  70  also, the group of strings  71  is desirably manufactured on a flat surface, and before being placed over the first protection component  12 , the second wiring members  31 A and  31 B extend straight in the lateral direction and the strings  20  extend straight in the longitudinal direction. In the present embodiment, the second wiring members  31 A placed adjacent to each other in the lateral direction are fixed to each other, the second wiring members  31 B placed adjacent to each other in the lateral direction are fixed to each other, and the second wiring members  31 A and  31 B placed adjacent to each other in the longitudinal direction between the blocks are fixed to each other, respectively, using the adhesion tape  32 . The group of strings  71  to which the adhesive tapes  32  are adhered is placed over the first protection component  12  and is laminated with the constituent members, to obtain the solar cell module  70  having the above-described structure. 
         [0064]    When the group of strings  71  is placed over the first protection component  12 , the second wiring member  31  fixed by the adhesion tape  32  is placed along the curved surface of the first protection component  12 , and the strings  20  positioned at the sides of the group of strings  71  in the lateral direction are also placed along the curved surface. For example, when the second wiring member  31  fixed by the adhesion tape  32  is placed along the curved surface of the first protection component  12 , a force to move the strings  20  positioned on the sides of the group of strings  30  in the lateral direction toward the inner side would act. However, because the second wiring members  31 A and  31 B positioned adjacent to each other in the longitudinal direction are fixed by the adhesion tape  32 , the strings  20  positioned at the sides of the group of strings  30  in the lateral direction do not move toward the inner side, and in fact, it can be expected that a force that pushes the string toward the outer side will act. With such a configuration, the solar cell module  70  can be obtained in which, in the group of strings  71 , the central portion in the lateral direction protrudes on the sides in the longitudinal direction and the central portion in the longitudinal direction protrudes on the sides in the lateral direction. 
         [0065]    In the above-described embodiments, a configuration is exemplified in which the numbers of solar cells of the strings are identical to each other, but alternatively, the numbers of solar cells in the strings may differ among blocks. Alternatively, the numbers of strings of the blocks may differ from each other. 
       REFERENCE SIGNS LIST 
       [0066]      10 ,  50 ,  70  SOLAR CELL MODULE;  11  SOLAR CELL;  12  FIRST PROTECTION COMPONENT;  13  SECOND PROTECTION COMPONENT;  14  ENCAPSULANT;  20 ,  20 Aa,  20 Ab,  20 Ac,  20 Ad,  20 Ae,  20 Af,  20 Ba,  20 Bb,  20 Bc,  20 Bd,  20 Be,  20 Bf STRING;  21  FIRST WIRING MEMBER;  30 ,  51 ,  71  GROUP OF STRINGS;  30 A,  30 B,  51 A,  51 B,  71 A,  71 B BLOCK;  31 ,  31 A,  31 B SECOND WIRING MEMBER;  32  ADHESION TAPE.