JP2014209654A - Solar battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar battery module that implements satisfactory power generation efficiency and a high production yield.SOLUTION: The solar battery module includes: a first solar battery group G1 and a second solar battery group G2 each including a predetermined number of solar battery cells C provided with electrodes of different polarities on a first main surface and a second main surface opposite to the first main surface, respectively, and tab wiring 11 electrically connecting in series the predetermined number of solar battery cells arranged in a straight line (X direction); and a connection member 12 electrically connecting in series a first solar battery cell C11 positioned at one end of the first solar battery group and a second solar battery cell C21 positioned at one end of the second solar battery group. The first solar battery group and the second solar battery group are arranged in a short end direction (Y direction) substantially perpendicular to the straight line, and the first solar battery cell and the second solar battery cell are arranged such that electrodes of different polarities face in the same direction.

Description

  The present invention relates to a semiconductor device that is sensitive to infrared rays, visible light, and short-wave electromagnetic waves, and more particularly to a solar cell module that converts these radiation energy into electrical energy.

  Solar cells are attracting attention as a new environmentally friendly energy source because they can directly convert light from the sun, a clean and inexhaustible energy source, into electricity.

  When such a solar battery is used as a power source (energy source), the output per solar battery cell is about several watts at most, so it is not used for each solar battery cell, but as shown below. In general, it is used as a solar cell module in which a plurality of solar cells are arranged in a matrix and these are electrically connected in series to increase the output to 100 W or more (for example, see Patent Document 1). ).

  First, a predetermined number of solar cells are arranged in a straight line, and these are connected in series by wiring or the like to form a plurality of strings. In addition, a plurality of solar cells are connected in series by alternately connecting different polarities of the plurality of solar cells by wiring. And a some string is arranged in a transversal direction, and the photovoltaic cells located in the edge part of an adjacent string are connected in series. Thus, by alternately connecting the ends of the strings, a plurality of solar cells arranged in a matrix can be connected in series.

  However, when a plurality of solar cells of the type in which a positive electrode and a negative electrode are formed on the front surface and the back surface of the solar cell, respectively, so that the same polarity is all on the front surface side, It is necessary to connect the front and back surfaces of the string solar cells. For the connection of the front and back surfaces, a flat connection member disposed outside the cell region outside the end of the string is used. This flat connection member forms an ineffective region that does not contribute to power generation outside the end of the string, and power generation efficiency is reduced.

  By the way, a back contact type solar battery cell in which both a positive electrode and a negative electrode are formed on the back surface of the solar battery cell is conventionally known (see, for example, Patent Document 2). By using this type of solar battery cell, a plurality of solar battery cells can be connected in series between the back surfaces, and the above-described invalid area can be reduced.

JP 2006-278904 A JP 2005-11869 A

  However, the structure of the positive electrode and the negative electrode formed on the back surface of the solar battery cell, and the structure of the comb-like electrode connected to the positive electrode and the negative electrode are complex, the positive electrode and the negative electrode, and the comb-like electrode connected to them. There were problems in the productivity and yield of each manufacturing process.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a solar cell module with good power generation efficiency and high production yield.

The present invention includes first and second solar cell groups each including a plurality of solar cells, and a first electrode and a back surface that are exposed on the surface of the first solar cell included in the first solar cell group. A second electrode that is exposed to the surface of the second solar cell included in the second solar cell group, a third electrode that is different in polarity from the first electrode, and a back surface that is exposed to the third electrode. A fourth electrode having a polarity different from that of the second electrode; a take-out electrode connected to an electrode exposed on the back surface of any one of the solar cells; and taking out generated power; the second electrode and the fourth electrode And a second connection member for electrically connecting the plurality of solar cells included in the first solar cell group or the second solar cell group, and And the plurality of solar cells constituting the plurality of solar cell groups are arranged. In the cell region, at least a part of the extraction electrode and the first connecting member are arranged substantially in parallel without overlapping in the thickness direction, and in the thickness direction, the surface of the first solar cell The first electrode and the second connection member are arranged in this order, and the second electrode and the first connection member overlap each other in this order on the back surface of the first solar cell. The third electrode and the second connection member are formed on the surface of the second solar battery cell in this order, and the fourth electrode and the first connection member are formed on the back surface in this order. Are joined in this order over the entire surface of each overlapping region.
It is.

Further, the first solar battery cell is a solar battery module including at least one solar battery cell, and the second solar battery cell is including at least one solar battery cell.

According to the first feature of the present invention, the first solar cell and the second solar cell are arranged such that electrodes having different polarities face in the same direction, and the first connection member includes The solar battery cell and the second solar battery cell are electrically connected in series. Therefore, the 1st connection member can connect the electrode which faced the same direction of the 1st photovoltaic cell and the 2nd photovoltaic cell within a cell field. Thereby, it is not necessary to connect the front surface / back surface of the first solar battery cell and the back surface / front surface of the second solar battery cell, and the first connection member is placed outside the first and second solar battery groups. There is no need to arrange it outside the cell area. Therefore, the invalid area by the connection member is reduced, the ratio of the cell area to the total area of the solar cell module is increased, and the power generation efficiency is improved. At the same time, the plurality of solar cells constituting the solar cell module are provided with electrodes having different polarities on the first and second main surfaces, respectively, so that the electrode structure is more than that of the back contact solar cell. It is not complicated and the productivity and yield of solar cells are high.

  In the first feature of the present invention, it is desirable that the first connecting member is disposed on the back side facing the surface of the solar cell module on which light is incident. The first connecting member does not block the light incident on the solar cell module, and the power generation efficiency can be further improved.

  In the first feature of the present invention, the predetermined number of solar cells constituting the first and second solar cell groups are alternately switched so that the polarities of the different electrodes of the adjacent solar cells are directed in the same direction. It is desirable that they are arranged. Since the surface or back surface of the adjacent photovoltaic cell of the same direction can be connected by tab wiring, since the space | interval of adjacent photovoltaic cell can be narrowed, the filling rate of a photovoltaic cell increases. At the same time, the disconnection failure of the wiring due to the warpage of the solar battery cell can be suppressed.

  In the first feature of the present invention, the solar cell has a regular hexagon or a pseudo regular hexagon, a first straight line connecting a pair of opposed vertices, and a set of opposed and orthogonal to the first straight line. It is desirable to have a shape obtained when dividing by a second straight line connecting the two division points of the side. The filling rate of the solar battery cells can be increased, and the utilization efficiency of the ingot that is the material of the cell substrate constituting the solar battery cells can be increased.

  Here, in the “pseudo regular hexagon”, a part of the circular arc portion of this circle is formed so as to form a regular hexagon larger than the regular hexagon inscribed in the predetermined circle and smaller than the regular hexagon inscribed in the circle. A shape formed by replacing the outer peripheral portion of the circle with a line segment while remaining, a shape formed by replacing the remaining arc portion with a line segment, and a shape in which a side or a corner is slightly changed are included.

  A second feature of the present invention relates to the first feature of the present invention, and is a surface-side protection member disposed on the surface side of the solar cell module on which light is incident, and a back surface side facing the surface of the solar cell module. A sealing material for sealing the first and second solar cell groups between the back surface side protective member disposed on the surface, the front surface side protective member and the back surface side protective member, and the first sun. An extraction electrode for extracting electric power from the battery group, and the sealing material includes a first sealing material that contacts the surface of the first and second solar cell groups, and a second electrode that contacts the back surface. The extraction electrode is connected to the back side of the third solar cell located at the other end of the first solar cell group, and the extraction electrode is connected to the second solar cell. Extending to the back side of the fourth solar cell located at the other end of the solar cell group, Between the back surface of the the out electrode 4 of the solar cell, it is that the second sealing member is disposed.

  According to the first feature of the present invention, the extraction electrode connected to the back side of the third solar cell located at the other end of the first solar cell group is connected to the other end of the second solar cell group. The back surface side sealing material is arrange | positioned between the extraction electrode and the back surface of the 4th photovoltaic cell extending in the back surface side of the 4th photovoltaic cell located.

  When the interface between the extraction electrode and the fourth solar battery cell is in an unbonded state, gas from the member stays at the interface due to this. The appearance of the solar cell module is impaired due to gas retention (exterior appearance defect). Therefore, the interface between the first extraction electrode and the back surface of the fourth solar cell is brought into an adhesive state by disposing the back surface side sealing material between the extraction electrode and the back surface of the fourth solar cell. Can do. Therefore, it is possible to suppress the outgas from the member from staying at the interface. Therefore, the appearance defect of the solar cell module due to gas retention can be suppressed.

  In the second aspect of the present invention, it is desirable that the sealing material further includes a third sealing material disposed between the extraction electrode and the back surface side protection member. The interface between the extraction electrode and the back surface side protective member can be brought into an adhesive state by the sealing material. Therefore, it is possible to further suppress the outgas from staying at the interface between the extraction electrode and the back surface side protection member.

  In the second feature of the present invention, a predetermined number of solar cells each provided with electrodes of different polarities on the first main surface and the second main surface opposite to the first main surface, and along a straight line And a fifth solar cell located at one end of the third solar cell group, each having a tab wiring that electrically connects the predetermined number of solar cells arranged in series electrically in series. And another connecting member that electrically connects the cell and the fourth solar cell in series, wherein the other connecting member includes the fourth solar cell and the fifth solar cell. It is desirable that the take-out electrode and the other connection member be separated on the back surface of the fourth solar battery cell. In the modularization process of the solar cell module, even when pressure from above and below is applied to the stacked body in which the respective members are stacked, it is possible to avoid stress concentration at one location of the solar cell. As a result, the occurrence of cell cracks in the modularization process can be suppressed.

  According to the present invention, it is possible to provide a solar cell module with high power generation efficiency and high production yield.

The top view which shows the structure of the solar cell module concerning the 1st Embodiment of this invention. The top view which shows the structure of the solar cell module concerning the modification of 1st Embodiment. The top view which shows the structure of the solar cell module concerning the 2nd Embodiment of this invention. FIG. 4A is a plan view in which a series connection portion between the fifth and sixth solar cell groups G05 and G06 is enlarged, and FIG. 4B is a cross-sectional view taken along the line AA in FIG. FIG. Sectional drawing along CC plane of Fig.4 (a). FIG. 6A to FIG. 6D are plan views for explaining the planar shape of the solar battery cell. The top view which shows the structure of the solar cell module concerning a comparative example. The top view which expanded the serial connection part between the 1st and 2nd solar cell groups G1 and G2 of FIG. FIG. 9A is a plan view showing another example of the serial connection portion of FIG. 8, and FIG. 9B is along the BB cut surface on which the connection member 43 of FIG. 9A is formed. Sectional drawing. The side view which shows the structure of the solar cell module concerning the 3rd Embodiment of this invention. The top view which shows the structure of the solar cell module concerning the 3rd Embodiment of this invention. The rear view which shows the structure of the solar cell module concerning the 3rd Embodiment of this invention. The rear view which shows the structure which attached the terminal box 106 to the back surface of the solar cell module concerning the 3rd Embodiment of this invention. The side view which shows the state before modularizing the solar cell module concerning the 3rd Embodiment of this invention. The top view which shows the structure which made the extraction electrode 105 penetrate the back surface side sealing material 103b concerning the 3rd Embodiment of this invention. The top view which shows the structure of the solar cell module concerning the modification of the 3rd Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In the description of the drawings, the same parts are denoted by the same reference numerals.

(First embodiment)
With reference to FIG. 1, the structure of the solar cell module concerning the 1st Embodiment of this invention is demonstrated. The solar cell module electrically connects a plurality of solar cell groups G1 to Gn formed by electrically connecting a predetermined number of solar cells arranged along a straight line in series, and the plurality of solar cell groups G1 to Gn. And a connecting member 12 connected in series. FIG. 1 illustrates a case where the solar cell module includes n solar cell groups. The n solar cell groups are referred to as first to nth solar cell groups G1 to Gn.

  Each of the first to nth solar cell groups G1 to Gn includes a predetermined number of solar cells C and a tab wiring 11 that electrically connects the predetermined number of solar cells arranged in a straight line in series. Is provided. In FIG. 1, the case where the 1st thru | or nth solar cell group G1-Gn is each provided with the m solar cell C1-Cm is demonstrated. The first solar cell group G1 includes solar cells C11 to C1m, and the second solar cell group G2 includes solar cells C21 to C2m. Similarly, the third to nth solar cell groups G3 to Gn include solar cells C31 to C3m, ..., Cn1 to Cnm.

The m solar cells C11 to C1m included in the first solar cell group G1 are arranged in order along a straight line (X direction). In each of the solar cells C11 to C1m, electrodes having different polarities are provided on the first main surface and the second main surface facing the first main surface, respectively. The m solar cells C11 to C1m are alternately arranged so that the polarities of different electrodes of adjacent solar cells face the same direction. The solar cells C11 to C1m have a photoelectric conversion unit that generates a photogenerated carrier by light incidence from both sides of the first and second main surfaces, and a positive / negative pair for taking out the photogenerated carrier generated by the photoelectric conversion unit. Electrode. A pair of positive and negative electrodes is provided on each of the first main surface and the second main surface. Here, a case where the positive electrode is formed on the first main surface side and the negative electrode is formed on the second main surface side will be described. The positive electrode (first main surface) of the solar cell C11, the negative electrode (second main surface) of the solar cell C12, the positive electrode (first main surface) of the solar cell C13, ... of the solar cell C1m The positive electrodes (first main surface) are arranged in the same direction.

The tab wiring 11 that electrically connects the m solar cells C11 to C1m in series is formed by connecting two adjacent electrodes by connecting electrodes exposed on the same side surface of two adjacent solar cells. Solar cells are electrically connected in series. The number of tab wirings 11 is m-1.
Each of the m−1 tab wirings 11 connects between the positive electrode exposed on the surface side of the solar battery cell C11 and the negative electrode exposed on the surface side of the solar battery cell C12, and the back surface side of the solar battery cell C12. Are connected between the positive electrode exposed to the negative electrode and the negative electrode exposed to the back surface side of the solar cell C13, and the positive electrode exposed to the back surface side of the solar cell C1m-1 and the back surface side of the solar cell C1m Connect between the negative electrodes exposed to.

The m solar cells C1 to Cm and the m-1 tab wirings 11 included in the other second to nth solar cell groups G2 to Gn are also the first except for the following differences. The solar cell group G1 has the same configuration as the m solar cells C11 to C1m and the m-1 tab wirings 11 included in the solar cell group G1. The difference is in the second, fourth, sixth,..., Nth solar cell groups G2, G4, G6,..., Gn, the negative electrode (second main surface) of the solar cell C1, The positive electrode (first main surface) of solar cell C2, the negative electrode (second main surface) of solar cell C3,..., The negative electrode (second main surface) of solar cell Cm are oriented in the same direction. Is arranged. That is, the order of replacement of the negative electrode and the positive electrode in the even-numbered solar cell groups G2, G4, G6,..., Gn with respect to the odd-numbered solar cell groups G1, G3, G5,. And reverse.

  The first to nth solar cell groups G1 to Gn are sequentially arranged in the short direction (Y direction) of the solar cell group substantially perpendicular to the straight line (X direction). Therefore, the solar cell C11 (first solar cell) located at one end of the first solar cell group G1 and the solar cell C21 (second solar cell) located at one end of the second solar cell group G2. ) Are arranged so that electrodes of different polarities face in the same direction. That is, the positive electrode (first main surface) of the solar cell C11 and the negative electrode (second main surface) of the solar cell C21 are arranged on the surface side of the solar cell module. Similarly, solar cell C2m (first solar cell) located at one end of second solar cell group G2 and solar cell C3m (second solar cell) located at one end of third solar cell group G3. Are arranged such that electrodes of different polarities face in the same direction, ..., solar cell Cn-11 (first solar cell) positioned at one end of the (n-1) th solar cell group Gn-1 The battery cell) and the solar battery cell Cn1 (second solar battery cell) positioned at one end of the n-th solar battery group Gn are arranged such that electrodes having different polarities face the same direction.

  The connecting member 12 electrically connects two solar cell groups G1 to Gn adjacent in the Y direction in series. The number of connecting members 12 is n-1. The n−1 connecting members 12 electrically connect the solar cells located at one ends of two solar cell groups G1 to Gn adjacent in the Y direction in series. Since the solar cells located at one end of the two solar cell groups G1 to Gn adjacent in the Y direction are arranged so that the electrodes having different polarities face the same direction, the connecting member 12 is provided on the back surface of the solar cell module. The electrodes exposed on the side or surface side are connected. In the example of FIG. 1, it has shown about the case where the electrode exposed on the back surface side of the solar cell module is connected. The connecting members 12 are respectively between the solar cell C11 and the solar cell C21, between the solar cell C2m and the solar cell C3m, between the solar cell C31 and the solar cell C41,. Between Cn-11 and the photovoltaic cell Cn1 is connected in series. In this way, the connection member 12 electrically connects the first to nth solar cell groups G1 to Gn in series.

  The solar cell module has a cell structure in which solar cells are arranged in an m × n matrix. A region where the m × n solar cells are arranged is referred to as a “cell region”. The connecting member 12 connects the solar cells adjacent in the Y direction within this cell region.

  The solar cell C1m and the solar cell Cnm located at both ends of a series of first to nth solar cell groups G1 to Gn electrically connected in series by the connecting member 12 include electric power generated by the solar cell module. Are connected to an output terminal T1 and an output terminal T2, respectively.

  According to the 1st Embodiment of this invention demonstrated above, the following effects are obtained.

Solar cell C11 (first solar cell) located at one end of first solar cell group G1 and solar cell C21 (second solar cell) located at one end of second solar cell group G2 are: The electrodes having different polarities are arranged in the same direction. The connection member 12 electrically connects the solar battery cell C11 (first solar battery cell) and the solar battery cell C21 (second solar battery cell) in series. Therefore, the connection member 12 can connect the electrodes facing in the same direction of the solar cell C11 (first solar cell) and the solar cell C21 (second solar cell) within the cell region. . Thereby, it becomes unnecessary to connect the front surface / back surface of the solar battery cell C11 (first solar battery cell) and the back surface / front surface of the solar battery cell C21 (second solar battery cell), and the connection member 12 is connected to the first member. It is not necessary to arrange the solar cell group G1 and the second solar cell group G2 outside the cell region. Therefore, the ineffective area by the connection member 12 is reduced, the ratio of the cell area to the total area of the solar cell module is increased, and the power generation efficiency is improved. At the same time, the plurality of solar cells constituting the solar cell module are provided with electrodes having different polarities on the first and second main surfaces, respectively, so that the electrode structure is different from that of the back contact solar cell. It is not complicated and the productivity and yield of solar cells are high. Therefore, according to the first embodiment of the present invention, it is possible to provide a solar cell module with high power generation efficiency and high production yield.

  The connection member 12 is disposed on the back side facing the surface of the solar cell module on which light is incident. Thereby, the connection member 12 does not block light incident on the solar cell module, and the power generation efficiency can be further improved.

The solar cells constituting the solar cell group are alternately arranged so that the polarities of different electrodes of adjacent solar cells face the same direction. Thereby, since the surface or back surface of the adjacent photovoltaic cell of the same direction can be connected by the tab wiring 11, since the space | interval of adjacent photovoltaic cell can be narrowed, the filling rate of a photovoltaic cell increases. .
At the same time, the disconnection failure of the wiring due to the warpage of the solar battery cell can be suppressed.

(Modification of the first embodiment)
In the first embodiment of the present invention described above, a case where all the solar cell groups (first to nth solar cell groups G1 to Gn) constituting the solar cell module are electrically connected in series will be described. However, the present invention is not limited to this. The present invention can also be applied to the case where some solar cell groups are connected in parallel.

  With reference to FIG. 2, the structure of the solar cell module concerning the modification of 1st Embodiment is demonstrated. The solar cell module has four solar cell groups (first to fourth solar cell groups G1 to G4) formed by electrically connecting a predetermined number of solar cells arranged in a straight line (X direction) in series. ) And the parallel connection member 14 that electrically connects the solar cell groups adjacent in the short direction (Y direction) and the solar cell group adjacent in the Y direction are electrically connected in series. And a connecting member 12.

The first to fourth solar cell groups G1 to G4 are arranged in order in the Y direction. The solar cell C11 located at one end of the first solar cell group G1 and the solar cell C21 located at one end of the second solar cell group G2 are arranged such that electrodes of the same polarity face each other in the same direction, The solar cell C1m located at the other end of the first solar cell group G1 and the solar cell C2m located at the other end of the second solar cell group G2 are arranged so that the electrodes having the same polarity face the same direction. Has been. Similarly, the solar cells C31, C3m located at both ends of the third solar cell group G3 and the solar cells C41, C4m located at both ends of the fourth solar cell group G4 have electrodes of the same polarity. It is arranged to face the same direction.

  In contrast, the solar cell C21 (first solar cell) located at one end of the second solar cell group G2 and the solar cell C31 (second solar cell) located at one end of the third solar cell group G3. The solar cells are arranged so that electrodes having different polarities face in the same direction. Specifically, the positive electrode (first main surface) of the solar cell C21 and the negative electrode (second main surface) of the solar cell C31 are arranged on the surface side of the solar cell module.

  The parallel connection member 14 includes electrodes of the same polarity of solar cells located at both ends of the first solar cell group G1 and the second solar cell group G2, and the third solar cell group G3 and the fourth solar cell. The electrodes of the same polarity of solar cells located at both ends of the battery group G4 are electrically connected to each other. Specifically, the parallel connection member 14 includes the solar cell C11 and the solar cell C21, the solar cell C1m and the solar cell C2m, the solar cell C31 and the solar cell C41, and the solar cell C3m and the solar cell, respectively. The electrodes of the same polarity exposed on the back side of the battery cell C4m are connected. Thus, the parallel connection member 14 electrically connects the electrodes having the same polarity of the solar cells located at both ends of the two solar cell groups adjacent in the Y direction.

  The solar cells located at both ends of the first solar cell group G1 and the second solar cell group G2 are arranged such that electrodes having the same polarity face each other in the same direction. The solar cells located at both ends of the third solar cell group G3 and the fourth solar cell group G4 are arranged such that electrodes having the same polarity face each other in the same direction. Therefore, the parallel connection member 14 connects the electrodes of the solar battery cells exposed on the back side or the front side of the solar battery module. In the example of FIG. 2, the case where the electrode exposed on the back surface side of the solar cell module is connected is shown.

The connection member 12 electrically connects the second solar cell group G2 and the third solar cell group G3 adjacent in the Y direction in series. Specifically, the connection member 12 is a solar battery cell C21 (first solar battery cell) located at one end of the second solar battery group G2 and a solar battery cell located at one end of the third solar battery group G3. C31 (second solar battery cell) is electrically connected in series. The solar cells located at one end of the second solar cell group G2 and the third solar cell group G3 are arranged so that electrodes having different polarities face the same direction. Therefore, the connection member 12 connects the electrodes of the solar battery cells exposed on the back side or the front side of the solar battery module. In the example of FIG. 2, the case where the electrode exposed on the back surface side of the solar cell module is connected is shown.

  The solar cell C2m and the solar cell C3m positioned at both ends of a series of second and third solar cell groups G2 and G3 electrically connected in series by the connecting member 12 include electric power generated by the solar cell module. Are connected to an output terminal T1 and an output terminal T2, respectively.

  About the predetermined number of photovoltaic cells which comprise the 1st thru | or 4th photovoltaic cell group G1-G4, and the tab wiring 11 which connects a predetermined number of photovoltaic cells, it is the same as the solar cell module shown in FIG. Therefore, the description is omitted.

As described above, the solar cells located at both ends of the solar cell groups connected in parallel are arranged so that electrodes having the same polarity face each other in the same direction. The parallel connection member 14 electrically connects between the solar cells located at one end of the solar cell group connected in parallel. Therefore, the parallel connection member 14 can connect the electrodes facing in the same direction of the solar cells located at one end of the solar cell group connected in parallel within the cell region. Thereby, it is not necessary to arrange the parallel connection member 14 outside the cell region. Therefore, the ineffective area by the parallel connection member 14 is reduced, the ratio of the cell area to the total area of the solar cell module is increased, and the power generation efficiency is improved. Therefore, according to the modification of the first embodiment, a solar cell module with good power generation efficiency can be provided.

  The parallel connection member 14 is disposed on the back side facing the surface of the solar cell module on which light is incident. Thereby, the parallel connection member 14 does not block the light incident on the solar cell module, and the power generation efficiency can be further improved.

  The connecting member 12 and the parallel connecting member 14 have been described as separate members, but may be integrated members.

(Second Embodiment)
With reference to FIG. 3, the structure of the solar cell module concerning the 2nd Embodiment of this invention is demonstrated. The solar cell module includes first to twentieth solar cell groups G01 to G20 formed by electrically connecting a predetermined number of solar cells arranged in a straight line (X direction) in series.
A predetermined number of solar cells are connected by tab wiring (not shown). The first to twentieth solar cell groups G01 to G20 are arranged in order in the short direction (Y direction). The 1st thru | or 20th solar cell group G01-G20 is electrically connected in series or parallel by the connection member or parallel connection member which is not shown in figure. The dotted line in FIG. 3 shows the connection direction of the plurality of solar cells by the tab wiring, the connection member, and the parallel connection member.

  The solar cells located at both ends of the five consecutive solar cell groups are arranged so that the electrodes having the same polarity face each other in the same direction. Specifically, the negative electrodes (second main surface) of the solar cells C0101, C0201, C0301, C0401, and C0501 are directed to the surface side of the solar cell module, and the solar cells C0112, C0212, C0312, C0412, and C0512 are directed. The positive electrode (first main surface) is directed. The same applies to the sixth to tenth solar cell groups G06 to G10, the eleventh to fifteenth solar cell groups G11 to G15, and the sixteenth to twentieth solar cell groups G16 to G20.

  By connecting the electrodes of the same polarity of the solar cells located at both ends of the five consecutive solar cell groups by the parallel connection members, the five consecutive solar cell groups are electrically connected in parallel. Has been. Specifically, the first to fifth solar cell groups G01 to G05, the sixth to tenth solar cell groups G06 to G10, the eleventh to fifteenth solar cell groups G11 to G15, and the sixteenth to twentieth solar cells. Of solar cells located at both ends of the solar cell groups G16 to G20 are electrically connected to each other by parallel connection members.

In contrast, a solar cell C0501 (first solar cell) located at one end of the fifth solar cell group G05 and a solar cell C0601 (second solar cell) located at one end of the sixth solar cell group G06. The solar cells are arranged so that electrodes having different polarities face in the same direction. Specifically, the negative electrode (second main surface) of solar cell C0501 and the positive electrode (first main surface) of solar cell C0601 are arranged on the surface side of the solar cell module. Similarly, a solar cell C1012 (first solar cell) located at one end of the tenth solar cell group G10 and a solar cell C1112 (second solar cell) located at one end of the eleventh solar cell group G11. Battery cell) is arranged such that electrodes having different polarities face in the same direction, and the solar battery cell C1501 (first solar battery cell) and the sixteenth solar battery located at one end of the fifteenth solar battery group G15. Solar cell C1601 (second solar cell) located at one end of group G16 is arranged such that electrodes having different polarities face the same direction.

The connecting members are between the fifth solar cell group G05 and the sixth solar cell group G06 adjacent in the Y direction, between the tenth solar cell group G10 and the eleventh solar cell group G11, and the fifteenth solar cell. The group G15 and the sixteenth solar cell group G16 are electrically connected in series. Specifically, the connecting member is a solar battery cell C0501 (first solar battery cell) located at one end of the fifth solar battery group G05 and a solar battery cell C0601 located at one end of the sixth solar battery group G06. (Second solar cells) are electrically connected in series. Similarly, the connecting members are a solar battery cell C1012 (first solar battery cell) located at one end of the tenth solar battery group G10 and a solar battery cell C1112 (first solar battery group G11). (Second solar cell), solar cell C1501 (first solar cell) located at one end of the fifteenth solar cell group G15, and solar cell C1601 (one solar cell C1601) located at one end of the sixteenth solar cell group G16 Second solar cells) are electrically connected in series. These solar cells to which the connection member is connected are arranged such that electrodes having different polarities face the same direction. Therefore, a connection member connects the electrode of the photovoltaic cell exposed on the back surface side or surface side of the solar cell module.

  In addition, although the connection member and the parallel connection member were demonstrated as another member, you may be an integral member.

  Solar cell modules C0112 to C0512 and solar cells C0112 to C0512 located at both ends of a series of first to twentieth solar cell groups G01 to G20 electrically connected in series by connection members include solar cell modules. An output terminal T1 and an output terminal T2 for taking out the generated electric power to the outside are connected to each other.

FIG. 4A enlarges the 2 × 2 solar cells C0501, C0502, C0601, and C0602 of the portion Ma1 in which the fifth and sixth solar cell groups G05 and G06 are electrically connected in series. It is a top view shown. With reference to Fig.4 (a), the structure of the connection member 12 and solar cell which connect the adjacent solar cell group electrically in series is demonstrated. The solar battery cell can generate photogenerated carriers by light incident from both surfaces of the first and second main surfaces. A plurality of narrow finger electrodes 21a and 21b and wide bus bar electrodes 22a and 22b are provided on the first and second main surfaces of the solar cells, respectively, in order to minimize the area that blocks incident light. For example, it is formed in a comb shape. The finger electrodes 21a and 21b are electrodes for collecting photogenerated carriers generated by the photoelectric conversion unit, and are arranged over almost the entire light incident surface of the photoelectric conversion unit. The bus bar electrodes 22a and 22b are electrodes for collecting photogenerated carriers collected by the plurality of finger electrodes 21a and 21b, and are formed in a line so as to intersect with all the finger electrodes 21a and 21b. Is done. Further, the number of bus bar electrodes 22a and 22b is appropriately set in consideration of the size and resistance of the solar battery cell.

Solar cells adjacent in the X direction are arranged so that electrodes of different polarities face the same direction. Therefore, tab wiring 11a, 11b is formed on the bus bar electrodes 22a, 22b of the solar battery cells and on the bus bar electrodes 22a, 22b of other solar battery cells adjacent in the X direction, which are formed on the front surface side or the back surface side of the solar battery module. The bus bar electrodes 22a and 22b and the tab wirings 11a and 11b are bonded via solder, whereby a predetermined number of solar cells adjacent in the X direction can be electrically connected in series. In the example of FIG. 4A, the bus bar electrode 22a of the solar battery cell C0501 and the bus bar electrode 22b of the solar battery cell C0502 formed on the surface side of the solar battery module are electrically connected by the tab wiring 11a. The bus bar electrode 22b of the solar battery cell C0601 and the bus bar electrode 22a of the solar battery cell C0602 formed on the surface side are electrically connected by the tab wiring 11a.

  FIG. 4B is a cross-sectional view taken along the line AA on the connection member 12 that electrically connects the solar battery cell C0501 and the solar battery cell C0601 of FIG. As described above, solar cell C0501 and solar cell C0601 adjacent in the Y direction are arranged such that electrodes having different polarities face the same direction. Therefore, the connection member 12 arrange | positions the connection member 12 on the bus-bar electrode 22b of the other photovoltaic cell C0601 adjacent to the Y-direction on the bus-bar electrode 22b of the photovoltaic cell C0501 formed in the back surface side of the solar cell module. And the solar cell group adjacent to a Y direction can be electrically connected in series by adhere | attaching the bus-bar electrode 22b and the connection member 12 via solder. The connecting member 12 connects the solar cells adjacent in the Y direction within the cell region. Although FIG. 4A and FIG. 4B show the case where the electrodes exposed on the back side of the solar cell module are connected, the electrodes exposed on the front side may be connected.

  As shown in FIG. 4A and FIG. 3, the planar shape of the solar battery cell constituting the solar battery module is a regular hexagon or a pseudo regular hexagon with rounded corners connected to a pair of opposing apexes. It has a shape obtained by dividing by one straight line and a second straight line connecting two divided points of one side orthogonal to and opposite to the first straight line. Details of the planar shape of the solar battery cell will be described later with reference to FIG.

  With reference to FIG. 5, the cross-sectional structure of a photovoltaic cell is demonstrated. FIG. 5 is a cross-sectional view taken along the line CC of FIG. The solar cell includes a substrate 31, an i-type layer 32, a p-type layer 33, a transparent conductive film 34, a surface side collecting electrode (finger electrode) 21a, a bus bar electrode 22a, an i-type layer 36, and an n-type. A layer 37, a transparent conductive film 38, a back-side collector electrode (finger electrode) 21b, and a bus bar electrode 22b are provided. Tab wiring 11a is formed on bus bar electrode 22a.

  The substrate 31 is an n-type single crystal silicon substrate. An i-type layer 32 made of intrinsic amorphous silicon and a p-type layer 33 made of p-type amorphous silicon are sequentially stacked on the first main surface side of the substrate 31. Further, a transparent conductive film 34 is laminated on the p-type layer 33, and a comb-shaped finger electrode 21a and a bus bar electrode 22a on the first main surface side are formed thereon. On the other hand, an i-type layer 36 made of intrinsic amorphous silicon and an n-type layer 37 made of n-type amorphous silicon are sequentially stacked on the second main surface side of the substrate 31. Further, a transparent conductive film 38 is laminated on the n-type layer 37, and a comb-shaped finger electrode 21b and a second main surface side bus bar electrode 22b are formed thereon. In the solar cell, both light incident from the first main surface and the second main surface is incident on the substrate 31, and an electromotive current is generated regardless of which surface is incident. The transparent conductive films 34 and 38 are made of a translucent material such as ITO, ZnO, or SnO2. The finger electrodes 21a and 21b and the bus bar electrodes 22a and 22b are made of a conductive metal material formed by firing, for example, silver paste or the like.

  The planar shape of the solar battery cell will be described with reference to FIGS. 6 (a) to 6 (d). The substrate 31 shown in FIG. 5 for forming the solar battery cell is formed by thinly cutting an ingot having a circular cross-sectional shape shown in FIG. The cut disc is referred to as a wafer 60. The wafer 60 is further divided into a plurality of parts and processed into a predetermined shape, whereby the substrate 31 is formed.

  For example, as shown in FIG. 6B, a square solar cell 62a as shown in FIG. 1 and FIG. 2 is formed by processing the wafer 60 into a square inscribed in the outer periphery thereof, and opposing pairs of squares. A first straight line PP connecting the two split points of the side of the line, and a second straight line QQ connecting the two split points of the pair of sides orthogonal to and opposite to the first straight line PP. The shape obtained when the square is divided.

  Moreover, as shown in FIG.6 (c), the photovoltaic cell 62b processes the wafer 60 into the regular hexagon inscribed in the outer periphery, and connects the 1st straight line PP which connects a pair of opposing vertex, and the said It has a shape obtained when it is divided by a second straight line QQ that connects two divided points of a pair of sides that are orthogonal to the first straight line PP.

Furthermore, as shown in FIG. 6D, the solar battery cell 62 c is formed by processing the wafer 60 into a pseudo regular hexagon and connecting a first pair of opposing vertices PP and the first straight line. It has a shape obtained when it is divided by a second straight line QQ that connects two dividing points of a pair of sides that are orthogonal to and opposite to PP. Here, the “pseudo regular hexagon” is an arc of this circle so as to form a regular hexagon larger than the regular hexagon inscribed in a predetermined circle (outer periphery of the wafer 60) and smaller than the regular hexagon inscribed in the circle. The shape formed by replacing the outer peripheral part of this circle with a line segment while leaving a part of the part, and the remaining arc part replaced with a line segment, and slightly changing the side and corner Things are included. The planar shape of the solar battery cell shown in FIG. 4A is obtained by replacing the remaining arc portion of the pseudo regular hexagon with a line segment.

  According to the 2nd Embodiment of this invention demonstrated above, the following effects are obtained.

As shown in FIG. 4, the solar cells C0501 and C0601 to which the connection member 12 is connected are arranged so that electrodes having different polarities face the same direction. Therefore, the connection member 12 connects the electrodes of the solar cells C0501 and C0601 exposed on the back side of the solar cell module. Therefore, the connection member 12 can connect the electrodes facing the same direction of the solar cells C0501 and C0601 within the cell region. Thereby, it is not necessary to connect the back surface / front surface of the solar battery cell C0501 and the front surface / back surface of C0601, and it is not necessary to arrange the connection member 12 outside the cell region. Therefore, the connecting member 12
The invalid area due to is reduced, the ratio of the cell area to the total area of the solar cell module is increased, and the power generation efficiency is improved. At the same time, the plurality of solar cells constituting the solar cell module are provided with electrodes having different polarities on the first and second main surfaces, respectively, so that the electrode structure is more than that of the back contact solar cell. It is not complicated and the productivity and yield of solar cells are high. Therefore, according to the second embodiment of the present invention, it is possible to provide a solar cell module with good power generation efficiency and high production yield.

  The solar cells located at both ends of the solar cell groups connected in parallel are arranged so that electrodes having the same polarity face each other in the same direction. Therefore, the parallel connection member can connect the electrodes facing in the same direction of the solar cells located at both ends of the solar cell group connected in parallel within the cell region. This eliminates the need to arrange the parallel connection members outside the cell region. Therefore, the invalid area by the parallel connection member is reduced, the ratio of the cell area to the total area of the solar cell module is increased, and the power generation efficiency is improved. Therefore, according to the second embodiment, a solar cell module with good power generation efficiency can be provided.

  The solar battery cell constituting the solar battery module has a regular hexagon or pseudo regular hexagon as shown in FIGS. 6C and 6D, and a first straight line PP connecting a pair of opposing vertices. , And a shape obtained by dividing the first straight line PP by a second straight line QQ connecting two split points of one side that is orthogonal to and opposite to the first straight line PP. Thereby, the filling rate of a photovoltaic cell can be raised and the utilization efficiency of the ingot used as the material of the board | substrate 31 which comprises a photovoltaic cell can be improved.

(Comparative example)
With reference to FIG. 7, the structure of the solar cell module concerning a comparative example is demonstrated. The solar cell module includes first to sixth solar cell groups G1 to G6 formed by electrically connecting a predetermined number of solar cells arranged along a straight line (longitudinal direction) in series. A predetermined number of solar cells are connected by tab wiring 61. The first to sixth solar cell groups G1 to G6 are arranged in order in the short direction perpendicular to the straight line. The first to sixth solar cell groups G <b> 1 to G <b> 6 are electrically connected in series by the connection member 42. Specifically, the solar cell C101 located at one end of the first solar cell group G1 and the solar cell C201 located at the end of the second solar cell group G2 are electrically connected in series by the connection member 42. Has been. Similarly, the solar battery cell C212 and the solar battery cell C312, the solar battery cell C301 and the solar battery cell C401, the solar battery cell C412 and the solar battery cell C512, the solar battery cell C501 and the solar battery cell C601 are respectively connected to the connecting member 42. Are electrically connected in series.

FIG. 8 is an enlarged plan view of a series connection portion between the first and second solar cell groups G1 and G2 in FIG. On the first main surface of each of the solar cells C101, C102, C201, C202, a plurality of narrow finger electrodes 51a and a wide bus bar electrode 52a are combined to form a comb shape. Although illustration is omitted, the finger electrode 51b and the bus bar electrode 52b are also formed in a comb shape on the second main surface. Since all the solar cells constituting the solar cell module are arranged so that the electrodes of the same polarity face the same direction, the tab wiring 61a is a bus bar electrode on the surface side of the solar cell adjacent in the longitudinal direction. An electrical connection is made between 52a and the bus bar electrode 52b on the back surface side. Further, the connecting member 42
Electrically connects between the bus bar electrode 52a on the front surface side and the bus bar electrode 52b on the back surface side of the solar cells adjacent in the short direction. In this case, the connection member 42 needs to be disposed outside the cell region outside the first solar cell group G1 and the second solar cell group G2. Therefore, an ineffective region is formed by the connection member 42, the ratio of the cell area to the total area of the solar cell module is reduced, and the power generation efficiency is reduced.

As shown in FIG. 9A, the connection member 43 can be arranged in the cell region. In this case, as shown in FIG. 9B, the connection member 43 is electrically connected to the bus bar electrode 52b on the back surface side of the solar battery cell C101 through the tab wiring 61b, and the solar battery through the tab wiring 61a. It is electrically connected to the bus bar electrode 52a on the surface side of the cell C201. The tab wiring 61b formed on the back surface side of the solar battery cell C201 and the connection member 43 are electrically insulated by the insulating film 45. Thus, since the insulating film 45 is required between the tab wiring 61b and the connection member 43, the thickness of the solar cell module increases. On the other hand, in the embodiment of the present invention, at one end of the solar cell group, the solar cells adjacent in the short direction are arranged so that the electrodes of different polarities face the same direction. The electrodes of solar cells facing the back side of the solar cell module are connected to each other. Therefore, the insulating film 45 in FIG. 9B becomes unnecessary.

(Third embodiment)
In the said 1st Embodiment and 2nd Embodiment, the wiring structure for connecting mainly several solar cell groups and several solar cells was demonstrated.

  In the present embodiment, the arrangement of extraction electrodes for extracting electric power generated by the solar cell module to the outside will be described. In the first embodiment and the second embodiment, the extraction electrodes described in this embodiment are described as the output terminal T1 and the output terminal T2.

(Schematic configuration of solar cell module)
Hereinafter, the configuration of the solar cell module according to the present embodiment will be described with reference to FIGS. 10 to 12. FIG. 10 is a diagram showing a configuration of the solar cell module 100 according to the present embodiment. FIG. 11 is a plan view showing the configuration of the surface side of the solar cell module 100 according to the present embodiment. FIG. 12 is a rear view showing the configuration of the back side of the solar cell module 100 according to the present embodiment.

  As shown in FIG. 10, the solar cell module 100 includes first to fourth solar cell groups G <b> 1 to G <b> 4 that are electrically connected in series, a tab wiring 11, a connection member 12, and a surface-side protection member 101. The back surface side protection member 102, the sealing material 103, the frame 104, the extraction electrode 105, and the terminal box 106 are provided.

The tab wiring 11 electrically connects m solar cells C41 to C4m in series. The tab wiring 11 connects two adjacent solar cells electrically in series by connecting electrodes exposed on the same side surface of two adjacent solar cells. Each of the m−1 tab wirings 11 connects between the positive electrode exposed on the front surface side of the solar battery cell C41 and the negative electrode exposed on the front surface side of the solar battery cell C42, and the back surface side of the solar battery cell C42. Between the positive electrode exposed to the negative electrode and the negative electrode exposed to the back surface side of the solar cell C43,..., The positive electrode exposed to the back surface side of the solar cell C4m-1 and the back surface side of the solar cell C4m Connect between the negative electrodes exposed to. The tab wiring 11 can be formed of a conductive material such as copper formed into a thin plate shape or a twisted wire shape.

  The connection member 12 electrically connects two solar cell groups G1 to G4 adjacent in the Y direction in series. The number of connecting members 12 is n-1. Each of the n−1 connecting members 12 electrically connects the solar cells located at one ends of two solar cell groups G1 to G4 adjacent in the Y direction in series. Since the solar cells located at one end of the two solar cell groups G1 to Gn adjacent in the Y direction are arranged so that the electrodes having different polarities face the same direction, the connecting member 12 is provided on the back surface of the solar cell module. The electrodes exposed on the side or surface side are connected. In the example of FIG. 12, it has shown about the case where the electrode exposed on the back surface side of the solar cell module 100 is connected. The connection member 12 is connected in series between the solar cell C11 and the solar cell C21, between the solar cell C2m and the solar cell C3m, and between the solar cell C31 and the solar cell C41. In this way, the connection member 12 electrically connects the first to fourth solar cell groups G1 to G4 in series.

  The surface side protection member 101 is disposed on the surface side of the solar cell module 100 on which light is incident. The surface side protection member 101 is comprised with glass etc., and protects the solar cell module 100 from the surface side.

  The back side protection member 102 is disposed on the back side facing the surface of the solar cell module 100. The back surface side protection member 102 is a film having weather resistance, and protects the solar cell module 100 from the back surface side.

  The sealing material 103 is composed of EVA (ethylene vinyl acetate) or the like, and includes a plurality of solar cell groups G1 to G4 that include tab wiring 11, connection members 12, front surface side protection members 101, and back surface side protection members 102. Seal between. It is an electrode for taking out electric power generated in a plurality of photovoltaic cells which constitute a plurality of solar cell groups G1-G4. The sealing material 103 includes a front surface side sealing material 103a in contact with the surfaces of the plurality of solar cell groups G1 to G4 and a back surface side sealing material 103b in contact with the back surface.

  The frame 104 is an outer frame made of aluminum or the like. Note that the frame 104 may be provided as necessary.

  The extraction electrode 105 is an electrode for extracting electric power generated by the solar cell module to the outside. The extraction electrode 105 includes a first extraction electrode 105a and a second extraction electrode 105b.

The first extraction electrode 105a is connected to the electrode shown on the back surface of the solar battery cell C1m located at one end of the first solar battery group G1. That is, the 1st extraction electrode 105a is connected to the photovoltaic cell C1m located in the end of the 1st thru | or 4th solar cell group G1-G4 electrically connected in series or in parallel. As shown in FIG. 12, the first extraction electrode 105a extends to the back side of the solar battery cell C2m located at one end of the second solar battery group G2. Moreover, the 1st extraction electrode 105a is the terminal box 1 arrange | positioned in the back surface of the solar cell module 100 from between the photovoltaic cell C3m located in the end of the 3rd photovoltaic group G3, and the photovoltaic cell C2m.
06.

  Similarly, the 2nd extraction electrode 105b is connected to the electrode exposed on the back surface of the photovoltaic cell C4m located at one end of the fourth solar cell group G4. That is, the 2nd extraction electrode 105b is connected to the photovoltaic cell located in the other end of the 1st thru | or 4th solar cell group G1-G4 electrically connected in series or in parallel. As shown in FIG. 12, the second extraction electrode 105b extends to the back side of the solar cell C3m located at one end of the third solar cell group G3. The second extraction electrode 105b is connected to the terminal box 106 disposed on the back surface of the solar cell module 100 from between the solar cell C2m and the solar cell C3m.

  The first extraction electrode 105a and the second extraction electrode 105b can be formed of a conductive material such as copper formed into a thin plate shape or a twisted wire shape. Also, in FIG. 12, the portions of the first extraction electrode 105a and the second extraction electrode 105b that have been lightly painted are subjected to insulation processing to ensure insulation from the solar cells C2m and C3m. Is desirable.

FIG. 13 is a rear view of the solar cell module according to the present embodiment. As shown in FIG. 13, one terminal box 106 is disposed on the back surface of the solar cell module 100.
The terminal box 106 stores one end of the first extraction electrode 105a and one end of the second extraction electrode drawn from the inside of the solar cell module 100. Space is saved by providing the terminal box 106 at the center of the back surface of the solar cell module.

(Placement of extraction electrode)
Next, the arrangement relationship between the extraction electrode 105 and the sealing material 103 will be described. FIG. 14 is an exploded view showing a state before the solar cell module 100 is modularized in the side view of the solar cells C1m to C4m.

  As shown in FIG. 14, on the back surface side of the solar battery cell C1m, the first extraction electrode 105a and the back surface side sealing material 103b are arranged in the order described. The first extraction electrode 105a is inserted into the back surface side sealing material 103b between the solar battery cell C1m and the solar battery cell C2m, and is drawn out to the back surface side. Therefore, the back surface side sealing material 103b and the 1st extraction electrode 105a are arrange | positioned in the order of description in the back surface side of the photovoltaic cell C2m. That is, the back surface side sealing material 103b is arrange | positioned between the back surface of the photovoltaic cell C2m, and the 1st extraction electrode 105a.

  Similarly, the 2nd extraction electrode 105b and the back surface side sealing material 103b are arrange | positioned in the order of description in the back surface side of the photovoltaic cell C4m. The second extraction electrode 105b is inserted into the back surface side sealing material 103b between the solar battery cell C4m and the solar battery cell C3m, and is drawn out to the back surface side. Therefore, the back surface side sealing material 103b and the 2nd extraction electrode 105b are arrange | positioned in the order of description in the back surface side of the photovoltaic cell C3m. That is, the back surface side sealing material 103b is disposed between the back surface of the solar battery cell C3m and the second extraction electrode 105b.

  As shown in FIG. 14, the solar cell module 100 according to this embodiment includes an additional sealing material 103 c disposed between the first extraction electrode 105 a and the second extraction electrode 105 b and the back surface side protection member 102. It has more.

  FIG. 15 is a plan view showing a state where the first extraction electrode 105a and the second extraction electrode 105b are inserted through the back surface side of the back surface side sealing material 103b. In FIG. 15, the portions represented by solid lines in the first extraction electrode 105 a and the second extraction electrode 105 b indicate that they are disposed on the front surface side of the back surface side sealing material 103 b, and are portions represented by broken lines. Indicates that it is disposed on the back surface side of the back surface side sealing material 103b.

(Modularization process)
The solar cell module 100 can be manufactured by the following modularization process.

  First, the surface side protection member 101, the surface side sealing material 103a, the 1st thru | or 4th solar cell group G1-G4, the back surface side sealing material 103b, the additional sealing material 103c, and the back surface side protection member 102 are described in order of description. A laminate is produced by laminating from below. The extraction electrode 105 is inserted through the back side sealing material 103 b, the additional sealing material 103 c, and the back side protection member 102.

  Next, the sealing material is melted by heating while applying pressure from above and below the laminate, and the first to fourth solar cell groups G1 to G4 are interposed between the front surface side protection member 101 and the back surface side protection member 102. Is sealed. By further heating the laminate, the sealing material is cured and the solar cell module 100 is manufactured. The extraction electrode 105 drawn out to the back surface of the solar cell module 100 is stored in the terminal box 106.

  According to the third embodiment of the present invention described above, the following functions and effects can be obtained.

  As shown in FIG.12 and FIG.14, the 1st extraction electrode 105a connected to the back surface side of the photovoltaic cell C1m located in the end of the 1st solar cell group G1 is one end of the 2nd solar cell group G2. The back surface side sealing material 103b is arrange | positioned between the 1st extraction electrode and the back surface of the photovoltaic cell C2m.

Here, when the interface between the first extraction electrode 105a and the solar battery cell C2m is in an unbonded state, gas from the member stays at the interface due to this. The appearance of the solar cell module 100 is impaired due to the stagnation of the gas (defective appearance). Therefore, by arranging the back surface side sealing material 103b between the first extraction electrode 105a and the back surface of the solar battery cell C2m, the interface between the first extraction electrode 105a and the back surface of the solar battery cell C2m is brought into an adhesive state. be able to. Therefore, it is possible to suppress the outgas from the member from staying at the interface.
Therefore, the appearance defect of the solar cell module 100 due to gas retention can be suppressed.

  Moreover, the back surface side sealing material 103b is inserted between the solar battery cell C1m and the solar battery cell C2m. Thereby, it can suppress that the outgas generated from a member retains between the photovoltaic cell C1m and the photovoltaic cell C2m. Therefore, the appearance defect of the solar cell module due to the outgas retention can be suppressed.

  The same effect can be obtained by disposing the back surface side sealing material 103b between the second extraction electrode 105b and the back surface of the solar battery cell C3m.

  Moreover, when the additional sealing material 103c is arrange | positioned at the back surface side of the 1st extraction electrode 105a, the interface of the 1st extraction electrode 105a and the back surface side protection member 102 can be made into an adhesion | attachment state. Therefore, it is possible to further suppress the outgas from staying at the interface between the first extraction electrode 105a and the back surface side protection member 102.

  Further, the connection member 12 that electrically connects the solar battery cell C2m and the solar battery cell C3m in series and the first extraction electrode 105a are separated from each other on the back surface side of the solar battery cell C2m. That is, the connection member 12 and the first extraction electrode 105 a do not overlap in the thickness direction of the solar cell module 100. Therefore, in the modularization step, it is possible to avoid stress concentration at one location of the solar battery cell even when pressure from above and below is applied to the stacked body in which the respective members are stacked. As a result, the occurrence of cell cracks in the modularization process can be suppressed.

(Modification of the third embodiment)
In the third embodiment, the case where all the solar cell groups (first to fourth solar cell groups G1 to G4) constituting the solar cell module are electrically connected in series has been described. Is not limited to this. The present invention can also be applied to the solar cell module shown in FIG. 3 described in the second embodiment.

  16 is a rear view of the solar cell module shown in FIG. 3 as viewed from the back side. In FIG. 16, the tab wiring for electrically connecting the solar cells in series is indicated by a broken line.

In FIG. 16, the electrodes of the same polarity of the solar cells located at both ends of the five consecutive solar cell groups are electrically connected to each other by the parallel connection member 110, whereby the five consecutive solar cell groups are electrically connected. Are connected in parallel. Further, the parallel connection members 110 are electrically connected in series with electrodes of different polarities of solar cells located at both ends of the solar cell group. In this modification, the parallel connection member 110 that connects the solar cells C0101 to C0501 and the parallel connection member 110 that connects the solar cells C0601 to C1001 are formed as one connection member. Moreover, the photovoltaic cell C1101-C
The parallel connection member 110 that connects 1501 and the parallel connection member 110 that connects the solar cells C1601 to C2001 are formed as one connection member. Furthermore, the parallel connection member 110 that connects the solar cells C0612 to C1012 and the parallel connection member 110 that connects the solar cells C1112 to C1512 are formed as one connection member.

Further, the parallel connection member 110 that connects the solar cells C0112 to C0512 also has a function as the first extraction electrode 105a. In this modification, as shown in FIG. 16, the parallel connection member 110 that connects the solar cells C0112 to C0512 and the first extraction electrode 105a are formed as one connection member. Similarly, the parallel connection member 110 that connects the solar cells C1612 to C2012 also has a function as the second extraction electrode 105b. In this modification, as shown in FIG. 16, the parallel connection member 110 that connects the solar cells C1612 to C2012 and the second extraction electrode 105b are formed as one connection member.

The 1st extraction electrode 105a is arrange | positioned at the back surface side of the photovoltaic cell C0612-C1012. In FIG. 16, the portion that performs the function as the first extraction electrode 105 a in the parallel connection member 110 is illustrated with light ink. A back surface side sealing material (not shown) is disposed between the first extraction electrode 105a and the solar cells C0612 to C1012. A back side sealing material is disposed on the back side of the parallel connection member 110 and the solar cells C0112 to C0512 that connect the solar cells C0112 to C0512. The first extraction electrode 105a is inserted between the solar cell C0612 and the solar cell C0712 through the back surface side sealing material, and is drawn out to the back surface side.

Similarly, the 2nd extraction electrode 105b is arrange | positioned at the back surface side of the photovoltaic cell C1112-C1512. In FIG. 16, the portion that performs the function as the second extraction electrode 105 b of the parallel connection member 110 is illustrated with light ink. A back surface side sealing material (not shown) is disposed between the second extraction electrode 105b and the solar cells C1112 to C1512. A back side sealing material is disposed on the back side of the parallel connection member 110 and the solar cells C1612 to C2012 that connect the solar cells C1612 to C2012. The 2nd extraction electrode 105b is penetrated by the back surface side sealing material between the photovoltaic cell C1512 and the photovoltaic cell C1612, and is pulled out by the back surface side.

  Accordingly, in FIG. 16, only the first extraction electrode 105a and the second extraction electrode 105b that are lightly ink-colored are arranged on the back surface side of the back surface side sealing material.

  Although not shown, it is desirable to further include an additional sealing material that covers the back surfaces of the first extraction electrode 105a and the second extraction electrode 105b.

  According to the modification of the third embodiment described above, the following operational effects are obtained.

  As shown in FIG. 16, the first extraction electrode 105a connected to the back surface side of the solar battery cell C0612 located at one end of the fifth solar battery group G5 includes the sixth to tenth solar battery groups G6 to G10. The back surface side sealing material is arrange | positioned between the 1st extraction electrode and the back surface of the photovoltaic cell C0612-C1012 extended to the back surface side of the photovoltaic cell C0612-C1012 located in one end of the.

  In this way, by arranging the back surface side sealing material between the first extraction electrode 105a and the back surface of the solar cells C0612 to C1012, the interface between the first extraction electrode 105a and the back surface of the solar cells C0612 to C1012. Can be brought into an adhesive state. Therefore, it is possible to suppress the outgas from the member from staying at the interface. Therefore, the appearance defect of the solar cell module 100 due to gas retention can be suppressed.

  Note that the same effect can be obtained by disposing a back surface side sealing material between the second extraction electrode 105b and the back surfaces of the solar cells C1112 to C1512.

As described above, the present invention has been described in terms of two embodiments and modifications thereof. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention.
From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the embodiment of the present invention, a solar cell having a HIT structure as shown in FIG. 5 has been described. However, a single crystal or polycrystalline Si solar cell having a pn junction formed by thermal diffusion, or other A solar battery cell having a configuration may be used.

  Thus, it should be understood that the present invention includes various embodiments and the like not described herein. Therefore, the present invention is limited only by the invention specifying matters according to the scope of claims reasonable from this disclosure.

DESCRIPTION OF SYMBOLS 11, 11a ... Tab wiring 12, 42, 43 ... Connection member 14 ... Parallel connection member 21a, 21b, 51a, 51b ... Finger electrode 22a, 22b, 52a, 52b ... Bus-bar electrode 31 ... Substrate 32, 36 ... i-type layer 33 ... p-type layer 34, 38 ... transparent conductive film 37 ... n-type layer 45 ... insulating film 60 ... wafer 61, 61a, 61b ... tab wiring 62a-62c ... solar cell 100 ... solar cell module 101 ... surface side protection member 102 ... Back side protection member 103 ... Sealing material 103a ... Front side sealing material 103b ... Back side sealing material 103c ... Additional sealing material 104 ... Frame 105 ... Electrode 105a ... Electrode 105b ... Electrode 106 ... Terminal box 110 ... Parallel connection Member C ... Solar cell G ... Solar cell group PP ... First straight line QQ ... Second straight line T1, T2 ... Output terminal

Claims (8)

A first and second solar cell group comprising a plurality of solar cells;
A first electrode exposed on the surface of the first solar cell included in the first solar cell group and a second electrode exposed on the back surface;
A fourth electrode that appears on the front surface of the second solar cell included in the second solar cell group and has a polarity different from that of the first electrode and a second electrode that appears on the back surface and has a polarity different from that of the second electrode. Electrodes,
An extraction electrode connected to the electrode exposed on the back surface of any of the solar cells and taking out generated power;
A first connection member for electrically connecting the second electrode and the fourth electrode;
A second connecting member that electrically connects the plurality of solar cells included in the first solar cell group or the second solar cell group, and
In the cell region where the plurality of solar cells constituting the plurality of solar cell groups are arranged, at least a part of the extraction electrode and the first connecting member are arranged substantially in parallel without overlapping in the thickness direction. Has been
In the thickness direction, the first electrode and the second connection member are arranged in this order on the surface of the first solar cell, and the second electrode and the first on the back surface of the first solar cell. And the connecting members in this order are joined to each other over the entire surface of the overlapping region,
In the regions where the third electrode and the second connection member overlap in this order on the surface of the second solar cell, and the fourth electrode and the first connection member overlap in this order on the back surface, respectively. Formed over the entire surface,
Solar cell module.   2. The solar cell module according to claim 1, wherein the first solar cell is composed of at least one solar cell, and the second solar cell is composed of at least one solar cell. The solar cell group is composed of solar cells arranged along a straight line,
The solar cell module according to claim 1 or 2, wherein a plurality of the solar cell groups are arranged.   The solar cell module according to claim 3, wherein the extraction wiring and the first connection member are connected to a solar cell located at one end of the solar cell group among the plurality of solar cell groups.   The solar cell module according to claim 4, wherein the first connection member is disposed on the one end side as compared with the extraction electrode.   The said extraction wiring and said 1st connection member are arrange | positioned on the photovoltaic cell located in the said one end side of at least 1 of the said several photovoltaic cell group. Solar cell module.   The solar cell module according to any one of claims 3 to 6, wherein the extraction wiring and the first connection member extend in a direction intersecting with the solar cell group. The solar cell module according to any one of claims 3 to 7, wherein the number of solar cell groups is larger than the number of solar cells constituting the solar cell group.

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