Solar battery module and method for manufacturing same

Abstract

A solar battery module (1) is provided with a plurality of solar battery string units (100). Each of the solar battery string units (100) includes a plurality of solar battery cell strings (11) formed by electrically connecting a plurality of solar battery cells (20) arranged along a first direction (D1), and the plurality of solar battery cell strings (11) are aligned in a second direction (D2) intersecting the first direction (D1) and are connected in parallel. The plurality of solar battery cells (20) adjacent to each other in the first direction (D1) are electrically connected in series, and the plurality of solar battery cells (20) adjacent to each other in the second direction (D2) are electrically connected in parallel. At least two adjacent solar battery string units (100) among the plurality of solar battery string units (100) are electrically connected in series.

Description

Solar cell module and manufacturing method thereof

[0001] The present disclosure relates to a solar cell module having a solar cell string unit and a method for manufacturing the solar cell module.

[0002] Solar cells are used to convert sunlight into electricity using the photovoltaic effect. For example, as shown in FIG. 17 , a solar cell module 90a using approximately rectangular crystalline silicon solar cells (solar cell 91) is widely used. Furthermore, the solar cell module 90a typically has six solar cell strings 93 connected in series. Each solar cell string 93 includes multiple solar cells 91, which are electrically connected in series with wiring. In this type of solar cell module 90a, output wiring 94 extends through a slit (not shown) on the back side, and a terminal box 95 is provided to cover the opening and extract the output of the solar cell module 90a. FIG. 18 shows a schematic configuration example of the terminal box 95.

[0003] In certain usage situations, if a solar cell module is partially shaded, the current value will decrease depending on the shade conditions, but even if just one solar cell is shaded, the solar cell module may completely stop generating power because the solar cells are connected in series. To prevent this, a solar cell module is generally used in which one bypass diode 97 is connected to, for example, two solar cell strings, as shown schematically in Fig. 18 (see, for example, Patent Document 1).

[0004] Japanese Patent Application Laid-Open No. 2020-098931

[0005] In the conventional solar cell module, if some of the multiple solar cells are shaded by a building or have foreign matter attached to them, they will not receive sunlight and will no longer generate electricity. When this happens, a bypass diode will function, but even if just one solar cell stops generating electricity, two solar cell strings will no longer contribute to power generation. This is fine for solar cell modules installed on rooftops where there is little shadowing. However, solar cell modules installed on mobile objects such as vehicles are frequently shaded. Therefore, if partial shading causes a power loss equivalent to two solar cell strings each time, this will have a significant impact on the overall power generation. Installing a bypass diode for each solar cell to prevent this would result in a complex structure and a significant cost impact.

[0006] The present disclosure has been made in consideration of the above-mentioned circumstances, and its purpose is to provide a solar cell module that can reduce the effect of reduced power generation due to partial shading and increase the actual power generation amount, and a method for manufacturing such a solar cell module.

[0007] The solution of the present disclosure is a solar cell module comprising a plurality of solar cell string units, each of which includes a plurality of solar cell strings formed by electrically connecting a plurality of solar cell arranged along a first direction, the plurality of solar cell strings being arranged and connected in parallel in a second direction intersecting the first direction, the plurality of solar cell strings being electrically connected in series with the plurality of solar cell strings being adjacent in the first direction, and the plurality of solar cell strings being electrically connected in parallel with the plurality of solar cell strings being adjacent in the second direction, and the plurality of solar cell string units being electrically connected in series.

[0008] Furthermore, in the solar cell module, it is preferable that the solar cell string has a plurality of solar cells arranged along the first direction electrically connected by a connection member, the connection member having a first wiring portion extending in the first direction and a second wiring portion connected to the first wiring portion and extending in a second direction intersecting the first direction, and that the solar cell string unit has a plurality of solar cell cells adjacent to each other in the first direction connected by the connection member and electrically connected in series, and a plurality of solar cell cells adjacent to each other in the second direction connected by the connection member and electrically connected in parallel.

[0009] In the solar cell module, the connection member may be disposed at least between the solar cell cells adjacent to each other in the first direction.

[0010] In the solar cell module, it is preferable that the solar cell is a back electrode type solar cell having an electrode on one side of a semiconductor substrate, and the electrodes include a first conductivity type cell electrode and a second conductivity type cell electrode, a first collector electrode connected to the first conductivity type cell electrode is provided on one side of the first direction of the semiconductor substrate, and a second collector electrode connected to the second conductivity type cell electrode is provided on the other side of the first direction, and the first wiring portion of the connecting member extending in one side of the first direction is connected to the first collector electrode of one of two solar cell adjacent to each other in the first direction, and the first wiring portion extending in the other side of the first direction is connected to the second collector electrode of the other solar cell.

[0011] Furthermore, in the solar cell module, it is preferable that the solar cell is a double-sided electrode type solar cell having, as electrodes, a surface electrode on the light-receiving surface side and a back electrode on the surface opposite the light-receiving surface, and that the first wiring portion extending in one direction of the first direction of the connecting member is connected to the surface electrode of one of two solar cell adjacent to each other in the first direction, and that the first wiring portion extending in the other direction of the first direction is connected to the back electrode of the other solar cell.

[0012] Furthermore, in the solar cell module, the solar cells may be double-sided electrode solar cells having, as electrodes, a surface electrode on the light-receiving surface side and a back electrode on the surface opposite the light-receiving surface, and the first wiring portion of the connecting member connects the surface electrode of one of the solar cells adjacent in the first direction to the back electrode of the other solar cell, and the second wiring portion of the connecting member may be arranged on the back side of the solar cells, intersect with the first wiring portion connected to the back electrode, and be connected to the first wiring portion.

[0013] Furthermore, a method for manufacturing a solar cell module according to each of the above-described solutions also falls within the scope of the technical idea of ​​the present disclosure, which is characterized in that the method for manufacturing the solar cell module includes a step of forming the solar cell string unit and a step of connecting a plurality of the solar cell string units in series.

[0014] According to the present disclosure, it is possible to stabilize the amount of power generated by a solar cell module.

[0015] 11( a ) and 11 ( b ) are plan views showing solar cells in a solar cell module; FIG. 11( a ) and 11 ( b ) are plan views showing a back surface side of a solar cell; FIG. 11( a ) and 11 ( b ) are plan views showing a solar cell in a solar cell module ... solar cell in a solar cell module; FIG. 11( a ) and 11 ( b ) are plan views showing a solar cell in a solar cell module; FIG. 11( a ) and 11 ( b ) are plan views showing a solar cell in a solar cell module; FIG. 11( a ) and 11 ( b ) are plan views showing a solar cell in a solar cell module; FIG. 11( a ) and 11 ( b ) are plan views showing a solar cell in a solar cell module; 1 is an explanatory diagram showing a configuration example of a terminal box of a conventional solar cell module, and FIG. 2 is an explanatory diagram showing a solar cell module according to a reference example configured with back electrode type solar cells, viewed from the back side.

[0016] Embodiments of the present disclosure will be described with reference to the drawings.

[0017] 1 is a plan view showing a solar cell module 1 according to a first embodiment of the present disclosure. Note that in Fig. 1, the solar cell module 1 is shown as viewed from the back surface side, which is the surface opposite to the light-receiving surface, and resin layers, protective members, and the like provided on the solar cell module 1 are not shown.

[0018] The solar cell module 1 includes a plurality of solar cell string units 100. As shown in Fig. 1, the solar cell module 1 has a structure in which a plurality of solar cell string units 100 are arranged in the second direction D2. Each solar cell string unit 100 included in the solar cell module 1 has a structure in which a plurality of solar cell strings 11, 11a that are long in the first direction D1 are arranged in the second direction D2.

[0019] 1 , the solar cell strings 11, 11a are adjacent to other solar cell strings 11, 11a included in one solar cell string unit 100. Furthermore, the solar cell string 11a included in one solar cell string unit 100 is adjacent to the solar cell string 11a included in the other solar cell string unit 100.

[0020] In the solar cell string unit 100, the solar cell string 11 is arranged at a position that is not adjacent to another adjacent solar cell string unit 100. In contrast, the solar cell string 11a is arranged at a position that is adjacent to another adjacent solar cell string unit 100.

[0021] FIG. 2 is a plan view showing a solar cell 20 provided in the solar cell strings 11 and 11a, and schematically showing the electrode structure on the back side. FIG. 3 is a plan view showing inter-cell wiring 30 as a connecting member provided in the solar cell strings 11 and 11a.

[0022] The solar cell strings 11, 11a provided in the solar cell string unit 100 include a plurality of solar cells 20. The plurality of solar cells 20 included in one solar cell string 11, 11a are arranged along a first direction D1. In the solar cell strings 11, 11a, the plurality of solar cells 20 arranged along the first direction D1 are electrically connected by inter-cell wiring 30, which is a connecting member. The plurality of solar cells 20 included in one solar cell string 11 are electrically connected in series by the inter-cell wiring 30.

[0023] The solar cell 20 is a back electrode type (back contact type) solar cell, and an electrode is provided on the back surface opposite the light-receiving surface of the semiconductor substrate 21. As shown in Fig. 2, the solar cell 20 is provided with a first conductivity type (e.g., n-type) cell electrode 231 and a second conductivity type (e.g., p-type) cell electrode 232 as electrodes on the back surface side of the semiconductor substrate 21. In Fig. 2, the first conductivity type cell electrode 231 is shown by a dashed line and the second conductivity type cell electrode 232 is shown by a solid line, making it easy to distinguish between the two electrodes.

[0024] The first conductivity type cell electrodes 231 and the second conductivity type cell electrodes 232 are provided as a number of linear electrodes extending in the same direction (first direction D1, which is the up-and-down direction in FIG. 2 ) on the back surface of the semiconductor substrate 21. The first conductivity type cell electrodes 231 and the second conductivity type cell electrodes 232 are provided alternately and parallel to each other, and are arranged at a predetermined interval from each other.

[0025] A first collector electrode 241 connected to a plurality of first conductivity type cell electrodes 231 is provided near one edge portion 211 in the first direction D1 of the semiconductor substrate 21 of the solar cell 20. The first collector electrodes 241 are provided at a plurality of locations spaced apart from one another in a direction (second direction D2) along the edge portion 211 of the semiconductor substrate 21. In the illustrated embodiment, three first collector electrodes 241 are provided in the edge portion 211 that is on the upper side of the solar cell 20 in the drawing.

[0026] Three second collector electrodes 242 connected to the plurality of second conductivity type cell electrodes 232 are provided at intervals from one another near the other edge portion 212 in the first direction D1 of the semiconductor substrate 21. The solar cell 20 is connected to the outside via these first collector electrodes 241 and second collector electrodes 242.

[0027] A silicon substrate made of polycrystalline silicon or single-crystalline silicon having n-type or p-type conductivity can be used as the semiconductor substrate 21. The first conductivity type cell electrode 231 and the second conductivity type cell electrode 232 can each be an electrode made of a metal such as silver or copper.

[0028] It is preferable that an anti-reflection structure (not shown) for suppressing light reflection, such as a textured structure, is provided on the light-receiving surface side of the solar cell 20. It is preferable that an anti-reflection film (not shown) having physical properties for suppressing light reflection is provided on the anti-reflection structure on the light-receiving surface side.

[0029] In this case, the anti-reflection film may be, for example, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, an aluminum oxide film, or a laminated film combining these films. A passivation film (interfacial passivation film, not shown) is preferably provided on the back surface of the semiconductor substrate 21. The passivation film may be, for example, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, an aluminum oxide film, or a laminated film combining these films.

[0030] An example of the connection member is an inter-cell wiring (interconnector). The inter-cell wiring 30 shown in Fig. 3 includes a first wiring portion 31 extending in a first direction D1 and a second wiring portion 32 extending in a second direction D2 so as to intersect with the first wiring portion 31. In the illustrated embodiment, the inter-cell wiring 30 includes a plurality of first wiring portions 31. The plurality of first wiring portions 31 are arranged to correspond to the shape of the cell electrodes, and in the illustrated embodiment, are arranged symmetrically with respect to the strip-shaped second wiring portion 32 that is long in the second direction D2.

[0031] In the inter-cell wiring 30 according to the exemplary embodiment, three first wiring portions 31 a extend in one direction in the first direction D1, and three first wiring portions 31 b extend in the other direction in the first direction D1. These first wiring portions 31 a, 31 b are all provided with the same shape. One first wiring portion 31 a and the other first wiring portion 31 b are arranged on the same straight line with the second wiring portion 32 in between, and are arranged to intersect the second wiring portion 32 in a substantially crisscross shape.

[0032] An end portion of the second wiring portion 32 in the second direction D2 is provided in a shape that extends further in the second direction D2 than the first wiring portion 31. An end portion 321 of the second wiring portion 32 extends to one side of the inter-cell wiring 30 in the second direction D2, and an end portion 322 of the second wiring portion 32 extends to the other side of the second direction D2.

[0033] The inter-cell wiring 30 preferably has openings 33 at intersections between the first wiring portions 31a, 31b and the second wiring portion 32. In the illustrated embodiment, the openings 33 are formed at three intersections between the first wiring portion 31 and the second wiring portion 32. Each opening 33 is elongated in the second direction D2 more than the first direction D1 and has a slit-like, rectangular, or rounded, approximately rectangular shape. Note that the shape of the openings 33 is not limited to that shown in FIG. 3 and may be, for example, an elliptical shape elongated in the second direction D2, or any other shape. The openings 33 are arranged at equal intervals along the second wiring portion 32. The inter-cell wiring 30 is preferably made of a conductive metal foil (e.g., copper foil), and the surface of the metal foil is preferably covered with solder or tin plating.

[0034] 4 is a plan view showing another example of inter-cell wiring as a connecting member. The inter-cell wiring 30a may be provided such that the lengths of the ends of the second wiring portion 32 are different from each other. For example, as shown in FIG. 4, the second wiring portion 32 of the inter-cell wiring 30a is provided such that one end 324 is longer than the other end 323. The end 323 is shorter than the end 322 shown in FIG. 3, and the end 324 has the same length as the end 321 shown in FIG. 3.

[0035] The inter-cell wiring 30a including the short end 323 does not necessarily have to have the short end on the right side in the drawing as shown in FIG. 4, but may have the opposite end on the left side that is short.

[0036] 5 and 6 are plan views showing examples of solar cell strings provided in the solar cell string unit 100. In Fig. 5 and Fig. 6, the solar cell string 11 is shown as viewed from the back surface side opposite to the light-receiving surface.

[0037] As shown in Figure 5, in one solar cell string 11, multiple solar cells 20 (for example, five solar cells 20 in Figure 5) are arranged opposite each other so that the second collector electrode 242 of one solar cell 20 adjacent to the first direction D1 and the first collector electrode 241 of the other solar cell 20 are butted against each other.

[0038] The inter-cell wiring 30 is arranged along the peripheral portions extending in the second direction D2 of the plurality of solar cell 20. In the illustrated embodiment, the inter-cell wiring 30 is arranged between the solar cell 20 adjacent to each other in the first direction D1 and on the peripheral portions of the solar cell 20 at both ends in the first direction D1. The plurality of first wiring portions 31 extending from the inter-cell wiring 30 in the first direction D1 are connected to the electrodes (collecting electrodes) of the solar cell 20, and the solar cell 20 adjacent to each other in the first direction D1 are connected in series. In this way, even if thermal stress due to temperature change acts on the inter-cell wiring 30 between adjacent solar cell 20, the openings 33 can prevent stress concentration, thereby making it possible to suppress damage to the inter-cell wiring 30.

[0039] 5 , the first wiring portions 31a of the inter-cell wiring 30 are connected to the second collector electrodes 242, and the first wiring portions 31b are connected to the first collector electrodes 241. A conductive adhesive such as solder, a conductive solder resin, or a conductive paste can be used to connect the inter-cell wiring 30 and the electrodes of the solar cell 20. The inter-cell wiring 30 and the electrodes of the solar cell 20 are preferably connected by welding.

[0040] In the solar cell string 11, the second wiring portion 32 of the inter-cell wiring 30 is longer than the length in the second direction D2 of the solar cell 20. In the embodiment shown in Fig. 5, the length L22 in the second direction D2 of the second wiring portion 32 is longer than the length L21 in the second direction D2 of the solar cell 20. Ends 321, 322 of the second wiring portion 32 are provided to extend outward beyond the peripheral portions of the solar cell 20 in the second direction D2. In this way, the length L22 in the second direction D2 of the second wiring portion 32 is set to a length such that both ends (321, 322) of the second wiring portion 32 protrude outward in the second direction D2 beyond the peripheral portions of the solar cell 20.

[0041] The solar cell strings 11, 11a included in the solar cell string unit 100 are not limited to the form shown in Fig. 5 and can be configured in various forms. For example, the solar cell strings 11, 11a shown in Fig. 6 use inter-cell wiring 30a as a connecting member. The multiple solar cells 20 are electrically connected by the inter-cell wiring 30a. The multiple solar cells 20 included in one solar cell string 11, 11a are electrically connected in series by the inter-cell wiring 30a.

[0042] One end 324 of the second wiring portion 32 of the inter-cell wiring 30a extends long in the second direction D2 of the solar cell 20. The other end 323 is long enough not to protrude outside the second direction D2 from the edge of the solar cell 20. The length L23 of the second wiring portion 32 in the second direction D2 is longer than the length L21 of the solar cell 20 in the second direction D2.

[0043] As a result, each of the solar cell strings 11, 11a is configured to include a plurality of solar cell strings 20 connected in series, and for example, the upper end portion in Figure 5 is a positive pole and the lower end portion in the figure is a negative pole.

[0044] As shown in Fig. 1, the solar cell module 1 includes two solar cell string units 100. The multiple solar cell strings that make up these solar cell string units 100 may be, for example, solar cell strings 11 and 11a shown in Fig. 5 or solar cell strings 11 and 11a shown in Fig. 6, or a combination thereof.

[0045] 1 , a solar cell module 1 includes a solar cell string unit 100 in which a plurality of solar cell strings 11, 11a are arranged in a second direction D2 that intersects with the first direction D1. The plurality of solar cell strings 11, 11a included in one solar cell string unit 100 are electrically connected in parallel. The inter-cell wirings 30, 30a of each solar cell string 11, 11a have ends extending in the second direction D2 connected to ends of adjacent inter-cell wirings 30, 30a.

[0046] For example, an end 322 of the second wiring portion of the inter-cell wiring 30 extending from the solar cell string 11 is connected to an end 324 of the second wiring portion 32 of the inter-cell wiring 30a extending from the adjacent solar cell string 11a. The inter-cell wirings 30a can also connect adjacent solar cell strings 11a by arranging the ends 324 opposite each other in the second direction D2 or by arranging the ends 323 and 324 opposite each other.

[0047] The solar cell string 11a in which the inter-cell wiring 30a includes the short end portion 323 is disposed at the end portion in the second direction D2 of the solar cell string unit 100, and can form the boundary portion between adjacent solar cell string units 100. The solar cell string 11a included in one solar cell string unit 100 and the solar cell string 11a included in the other solar cell string unit 100 are not electrically connected in parallel. The end portion 323 of the second wiring portion 32 of the inter-cell wiring 30a does not overlap the end portion 323 of the second wiring portion 32 of the other adjacent solar cell string unit 100, and can be disposed apart from each other.

[0048] The inter-cell wirings 30a are configured so that the ends 323 of the inter-cell wirings 30a connected to adjacent solar cell strings 11a are opposed to each other in the second direction D2, thereby preventing the inter-cell wirings 30a from overlapping. Furthermore, if the ends 324 are opposed to each other in the second direction D2 or if the ends 323 and 324 are opposed to each other, the inter-cell wirings 30a will overlap each other.

[0049] The solar cell module 1 configured in this manner has a connection structure in which the solar cell cells 20 are connected in series and in which the solar cell cells 20 are connected in parallel in each solar cell string unit 100. That is, the solar cell cells 20 of the solar cell string units 100 included in the solar cell module 1 all have a series-parallel connection structure in which the solar cell cells 20 are connected in series and in parallel.

[0050] Furthermore, the multiple solar cell string units 100 included in the solar cell module 1 are electrically connected in series. As shown in Fig. 1 , the solar cell module 1 is configured by electrically connecting two solar cell string units 100, 100 having a series-parallel connection structure via a jumper wiring 34. The jumper wiring 34 connects one solar cell string unit 100 to the other solar cell string unit 100 in series. The jumper wiring 34 connects the negative pole of one solar cell string unit 100 to the positive pole of the other solar cell string unit 100.

[0051] More specifically, the first wiring portion 31 of the inter-cell wiring 30a at the negative pole side end of the solar cell string 11a that constitutes one solar cell string unit 100 and the first wiring portion 31 of the inter-cell wiring 30a at the positive pole side end of the solar cell string 11a that constitutes the other solar cell string unit 100 are connected by a jumper wiring 34.

[0052] As a result, the solar cell module 1 has a solar cell string unit 100 having a connection structure of both solar cell cells 20 connected in series and solar cell cells 20 connected in parallel. If a solar cell 20 is in a reverse bias state due to the influence of partial shading, the solar cell 20 with a reduced current value is thought to become an electrical resistor, but because of the series-parallel connection structure, current flows through a parallel connection circuit that bypasses that solar cell 20.

[0053] As a result, if the power generation capacity of one cell decreases due to partial shading, in a solar cell module with a conventional structure, the bypass diode will function and the two solar cell strings including that solar cell will no longer contribute to power generation.However, with this structure, the power reduction is limited to the solar cell that is partially shaded, so the reduction in power generation capacity of the solar cell module 1 can be suppressed and the power generation capacity can be stabilized.

[0054] 7 is an explanatory diagram showing one step of the method for manufacturing the solar cell module 1. The solar cell string unit 100 provided in the solar cell module 1 can be configured, for example, by arranging a plurality of solar cell strings 11 in the second direction D2. To manufacture the solar cell module 1, first, solar cell strings are manufactured and then connected to each other.

[0055] The solar cell string 11 is fabricated by arranging a plurality of solar cells 20 along the first direction D1 and electrically connecting the solar cells 20 adjacent to each other in the first direction D1 in series via inter-cell wiring 30 (string fabrication process). The first wiring portions 31a of the inter-cell wiring 30 are connected to the second collector electrodes 242, and the first wiring portions 31b are connected to the first collector electrodes 241. In the string fabrication process, a plurality of such solar cell strings 11 are fabricated. The solar cell string 11a can be fabricated in the same manner.

[0056] The solar cell strings 11, 11a fabricated in the string fabrication process have second wiring portions 32 extending in at least one direction in the second direction D2. In other words, at least one end of the second wiring portion 32 is provided extending outward beyond the edge portion in the second direction D2 of the solar cell 20. The solar cell string unit 100 is configured such that the second wiring portion 32 extending from the solar cell strings 11, 11a is connected to the second wiring portion 32 extending from another adjacent solar cell string 11, 11a.

[0057] For example, when fabricating the solar cell string unit 100 using the solar cell string 11, one end 321 of the second wiring portion 32 extending from the solar cell string 11 is connected to the other end 322 of the second wiring portion 32 extending from another solar cell string 11 adjacent to the solar cell string 11 in the second direction D2 so as to overlap with the other end 322, as shown in Fig. 7 . Alternatively, the other end 322 may be connected to the one end 321 so as to overlap with the other end 321.

[0058] The second wiring portions 32 of both inter-cell wirings 30 can be connected using a conductive adhesive such as solder, a conductive solder resin, or a conductive paste, similar to the connection of the electrodes. In the solar cell string unit 100, a plurality of solar cell strings 11 are arranged side by side in the second direction D2 and connected to each other. Adjacent solar cell strings 11 are arranged with the same polarity, so that one side in the first direction D1 is a positive pole and the other side is a negative pole. In the second direction D2, the solar cell strings 11 are arranged so that the peripheral portions of the solar cells 20 that are not provided with the first collector electrode 241 or the second collector electrode 242 abut each other.

[0059] The solar cell string unit 100 can be fabricated by connecting the end 321 to the end 322 of the second wiring portion 32 of a predetermined number of solar cell strings 11, or by connecting the end 324 of the second wiring portion 32 of the solar cell string 11a. For example, in the example shown in FIG. 1 , two solar cell string units 100 are fabricated, each including 15 solar cells 20 arranged adjacently in three columns and five rows. The solar cell cells 20 arranged adjacently in the first direction D1 are connected in series via the inter-cell wiring 30. The solar cell cells 20 arranged adjacently in the second direction D2 are connected in parallel via the inter-cell wiring 30.

[0060] The solar cell module 1 can be obtained by laminating a sealing resin such as an EVA sheet and a transparent substrate on the light-receiving surface side of the solar cell 20 in the solar cell string unit 100 produced in this manner, and laminating a sealing resin such as an EVA sheet and a back sheet on the back surface side, and then laminating them using thermocompression bonding or the like.

[0061] This makes it possible to obtain a solar cell module 1 in which two solar cell string units 100, each made up of solar cells 20 having both series connection and parallel connection structures, are electrically connected in series.

[0062] If partial shading causes a solar cell 20 to be in a reverse bias state, the solar cell 20 with a reduced current value is thought to become an electrical resistor, but because the solar cell 20 has a series-parallel connection structure, current flows through a parallel connection circuit that bypasses the solar cell 20. If the power generation amount of one solar cell 20 decreases due to partial shading, in a solar cell module with a conventional structure, the bypass diode will function, and the two solar cell strings including that solar cell will no longer contribute to power generation.

[0063] In contrast, with the solar cell module 1 according to this embodiment, the power reduction is limited to the solar cell 20 that is partially shaded, which makes it possible to suppress the reduction in the amount of power generated by the solar cell module 1 and stabilize the amount of power generated.

[0064] FIG. 19 is a plan view showing a solar cell module 90b according to a reference example configured with back electrode type solar cells 20, as viewed from the back surface side.

[0065] In the solar cell string 80 included in the solar cell module 90b, the length of the inter-cell wiring 81 in the second direction D2 is shorter than the length of the solar cell 20 in the second direction D2. In a conventional manufacturing process, the solar cell string 80 is first fabricated by connecting the solar cell 20 in series, and then the solar cell strings 80 are connected in series with wiring members 98, and the wiring members 98 and the connecting wires 99 are insulated by an insulating film. Therefore, the polarities of adjacent solar cell strings 80 (series connection directions) are opposite to each other.

[0066] In contrast, the solar cell module 1 according to this embodiment differs from conventional solar cell modules in that it is only necessary to connect the second wiring portions 32 of adjacent inter-cell wiring 30 together while aligning the polarity directions (series connection direction) of the solar cell strings 11, 11a, which makes it easy to work with and align the positions, and allows for simple and accurate manufacturing.

[0067] In the solar cell module 1, the solar cell cells 20 constituting the solar cell strings 11, 11a are not limited to those illustrated in the example, and may be solar cell cells having the same shape and the same area. The number of solar cell cells 20 included in each solar cell string 11, 11a is five, but this number is not limited to this and may be more or less than five. The number of solar cell strings 11 included in the solar cell string unit 100 is six in the example, but is not limited to six and may be any predetermined number.

[0068] Second Embodiment FIG. 8 is a plan view showing a solar cell module 1 according to a second embodiment as viewed from the back side, and FIG. 9 is an explanatory diagram showing a manufacturing method thereof.

[0069] The solar cell module 1 including the solar cell string 11a may be configured to have a solar cell string unit 101 in which a conventional solar cell string 80 and the solar cell string 11a shown in FIG. 6 are combined.

[0070] 9 , in a conventional solar cell string 80, the length of the inter-cell wiring 81 in the second direction D2 is shorter than the length of the solar cell 20 in the second direction D2. In contrast, in the solar cell string 11a, as described above, the length of the inter-cell wiring 30a in the second direction D2 is longer than the length of the solar cell 20 in the second direction D2, and a short end 323 and a long end 324 are provided. Therefore, for example, it is also possible to configure a solar cell string unit 101 by connecting the long end 324 of the second wiring part 32 to the inter-cell wiring 81 of the solar cell string 80.

[0071] As shown in Fig. 8, the solar cell module 1 has three solar cell string units 101, each including the solar cell string 11a shown in Fig. 6. The multiple solar cell string units 101 included in the solar cell module 1 are electrically connected in series.

[0072] As shown in Fig. 8 , the photovoltaic string units 101 are electrically connected to each other by a connecting wire 34. The connecting wire 34 connects one photovoltaic string unit 101 in series with the other photovoltaic string unit 101. In this case, the connecting wire 34 connects the negative pole of one photovoltaic string unit 101 to the positive pole of the other photovoltaic string unit 101.

[0073] In the solar cell module 1 according to this embodiment, the solar cell string unit 101 can also be configured to have a connection structure for both series-connected solar cells 20 and parallel-connected solar cells 20, making it possible to solve the problem of reduced power generation due to the influence of partial shading. Furthermore, the solar cell module 1 according to this embodiment has three solar cell string units 101 connected in series, so the voltage is even higher than that of the solar cell module of embodiment 2. In this way, multiple solar cell string units 101 can be formed in one module and connected in series, and desired solar cell module characteristics can be obtained by setting any number of parallel and series connections.

[0074] To fabricate such a solar cell module 1, a conventional manufacturing process can be used in which solar cell strings 11a, 80 are first fabricated and then connected to each other. As in the first embodiment, the solar cell string unit 101 is fabricated by arranging multiple solar cell strings in the second direction D2 while aligning the polarity direction (series connection direction) of each solar cell string, and then connecting the second wiring portion 324 of the inter-cell wiring 30a to adjacent inter-cell wiring. This allows for high workability, easy alignment, and simple, accurate fabrication. Then, as in the first embodiment, the solar cell string units 101 are connected in series. Although the polarity directions (series connection direction) of adjacent solar cell string units 100 are opposite to each other, the orientation can be set individually for each solar cell string unit. This allows for high workability, easy alignment, and simple, accurate fabrication.

[0075] (Embodiment 3) Fig. 10 is a plan view showing a solar cell module 1 according to embodiment 3 of the present disclosure. Fig. 11 shows a solar cell 40 constituting the solar cell module 1, Fig. 11(a) is a plan view showing the light-receiving surface side of the solar cell 40, and Fig. 11(b) is a plan view showing the back side of the solar cell 40. Fig. 12 is a plan view schematically showing an example of a connecting member in the solar cell module 1 according to embodiment 3. Fig. 13 is a plan view showing a solar cell string 12 provided in the solar cell module 1 according to embodiment 3.

[0076] The solar cell module 1 according to this embodiment includes a plurality of solar cell string units 102, and a plurality of solar cell strings 12 are arranged in each solar cell string unit 102. The solar cell 40 constituting the solar cell string 12 is a flat-plate photovoltaic element that generates power when irradiated with light, and is a double-sided electrode solar cell that includes a front electrode 41 and a back electrode 42.

[0077] 11( a), for example, a solar cell 40 has a surface electrode 41 provided on its light-receiving surface side, and the surface electrode 41 includes busbar electrodes and finger electrodes (not shown). The busbar electrodes of the surface electrode 41 are provided linearly in a first direction D1 on the light-receiving surface of the solar cell 40. The finger electrodes are formed linearly from the busbar electrodes in a second direction D2.

[0078] 11(b), the back surface electrode 42 of the solar cell 40 is provided opposite the front surface electrode 41, and includes, for example, a bus bar electrode and a finger electrode (not shown). The bus bar electrode of the back surface electrode 42 is provided linearly in the first direction D1 on the back surface of the solar cell 40. The finger electrode is formed linearly from the bus bar electrode in the second direction D2.

[0079] A plurality of pads 43 are provided on the busbar electrodes (collecting electrodes) to improve adhesion with wiring materials such as wires and to reduce contact resistance for connection, and end pads 44 are also provided on the ends of the solar cell 40 in the first direction D1. These pads 43 and end pads 44 have a relatively wide width and can serve as regions for attaching and fixing the first wiring portions 51 of the inter-cell wiring 50 and the like.

[0080] 12 , the inter-cell wiring 50 serving as a connecting member includes a plurality of first wiring portions 51 (51 a, 51 b) extending in a first direction D1 and a second wiring portion 52 extending in a second direction D2 so as to intersect with the first wiring portions 51. The plurality of first wiring portions 51 are arranged in accordance with the shape of the cell electrodes, and in the illustrated embodiment, are arranged symmetrically with respect to the strip-shaped second wiring portion 52 that is long in the second direction D2.

[0081] The first wiring portion 51 is a wire-shaped (or linear) conductive member. Specifically, the first wiring portion 51 is a wire-shaped wiring material (interconnector wire) having a configuration in which the outer surface of a wire having a substantially circular cross section is coated with a conductive adhesive or solder. The material of the wire is not particularly limited, but may be a metal such as copper.

[0082] 13 , the second wiring portion 52 of the inter-cell wiring 50 has a length L25 in the second direction D2 that is longer than the length L24 in the second direction D2 of the solar cell 40. An end portion 521 of the second wiring portion 52 extends to one side of the inter-cell wiring 50 in the second direction D2, and an end portion 522 of the second wiring portion 52 extends to the other side of the second direction D2. The second wiring portion 52 is a wire-shaped, linear, or strip-shaped conductive member, and the outer surface may be coated with a conductive adhesive or solder.

[0083] The length L26 ( FIG. 12 ) in the first direction D1 of the inter-cell wiring 50 including the first wiring portions 51 a, 51 b is shorter than the length L27 ( FIG. 13 ) in the first direction D1 of two solar cell cells 40, 40 adjacent to each other in the first direction D1. The inter-cell wiring 50 may have openings at the intersections of the first wiring portion 51 and the second wiring portion 52. The openings may be formed at the intersections of the first wiring portion 51 and the second wiring portion 52. The openings may have a shape that is longer in the second direction D2 than in the first direction D1, and may be elliptical, slit-shaped, rectangular, or rounded, approximately rectangular. The openings may be arranged at equal intervals along the second wiring portion 52.

[0084] In the solar cell string 12, the inter-cell wiring 50 is arranged between solar cells 40 adjacent to each other in the first direction D1. A first wiring portion 51a of the inter-cell wiring 50 extending in one direction in the first direction D1 is connected to the front surface electrode 41 of one of two solar cells 40 adjacent to each other in the first direction D1, and a first wiring portion 51b extending in the other direction in the first direction D1 is connected to the back surface electrode 42 of the other solar cell 40. The first wiring portion 51 is connected to the front surface electrode 41 and the back surface electrode 42 of the solar cell 40 by a conductive adhesive such as solder or conductive paste. The multiple solar cells 40 arranged adjacent to each other in the first direction D1 are electrically connected in series by the first wiring portions 51a, 51b extending in the first direction D1.

[0085] As shown in Fig. 10 , the solar cell module 1 can be configured such that a plurality of solar cell string units 102 are connected in series with wiring material 53. The solar cell string unit 102 includes at least one solar cell string 12 using inter-cell wiring 50 in which second wiring portions 52 extend only in one direction in the second direction D2 and do not extend in the other direction. The solar cell string unit 102 can be fabricated by connecting adjacent inter-cell wiring 50 while aligning the polarity of the solar cell strings 12. The number of solar cell strings 12 constituting one solar cell string unit 102 is not limited to the illustrated embodiment and can be set as desired.

[0086] In the solar cell module 1 according to this embodiment, multiple solar cell string units 102 are formed in one solar cell module 1 and are connected in series, and by setting any number of parallel and serial connections, the desired solar cell module characteristics can be obtained.

[0087] Furthermore, to fabricate such a solar cell module 1, a conventional manufacturing process for fabricating solar cell strings and connecting the solar cell strings can be used. The solar cell string unit can be fabricated simply by connecting the second wiring portions 52 of the inter-cell wiring 50 while aligning the polarity directions (series connection direction) of the solar cell strings 12. This facilitates easy alignment and allows for simple and accurate fabrication. Since the solar cell string units are connected in series, the polarity directions (series connection direction) of adjacent solar cell string units are opposite to each other. However, since the orientation can be set for each solar cell string unit, this facilitates easy alignment and allows for simple and accurate fabrication.

[0088] 17 , solar cell module 90a having a conventional structure is configured such that solar cell strings 93 are first formed by connecting solar cells 91 in series, and then the solar cell strings 93 are connected in series. Therefore, the polarities of adjacent solar cell strings 93 (series connection directions) are opposite to each other.

[0089] In contrast, the solar cell module 1 according to this embodiment differs from conventional solar cell modules in that adjacent inter-cell wirings 50 can be connected to each other while aligning the polarity directions (series connection direction) of the solar cell strings 12, which makes it easy to work with and align the positions, and allows for simple and accurate fabrication.

[0090] By providing a solar cell module having the structure of this embodiment, it is possible to provide a solar cell module that can suppress the influence of a decrease in power generation due to partial shading and increase the effective power generation amount. Furthermore, by appropriately using a string such as the solar cell string 12 in the solar cell module, the number of solar cells connected in series and in parallel can be selected as desired, making it possible to provide a solar cell module with desired electrical characteristics.

[0091] In addition, the solar cell string 12 can be produced by arranging multiple solar cells 40 along the first direction D1 and electrically connecting adjacent solar cells 40 in the first direction D1 in series with inter-cell wiring 50 (string production process).

[0092] The number of solar cells 40 constituting the solar cell string 12 is not limited to the illustrated number. Furthermore, in the inter-cell wiring 50 illustrated in Fig. 12 , the length L25 of the second wiring portion 52 in the second direction D2 is longer than the length L24 of the solar cell 40 in the second direction D2, and the second wiring portion 52 extends on both sides in the second direction D2, but the second wiring portion 52 may extend on only one side in the second direction D2. The solar cell string unit may be formed by appropriately combining inter-cell wirings 50 in which the second wiring portion 52 extends on both sides in the second direction D2, in which the second wiring portion 52 extends on only one side, and in which the second wiring portion 52 does not extend on either side in the second direction D2.

[0093] Fourth Embodiment FIG. 14 is a plan view schematically showing a solar cell module 1 according to a fourth embodiment of the present disclosure.

[0094] The solar cell module 1 of the present disclosure may have a configuration different from that of the third embodiment, including double-sided electrode solar cells 40 and having a series-parallel connection structure.

[0095] As shown in Figure 14, the solar cell module 1 according to this embodiment includes a plurality of solar cell string units 103 each having a structure in which a plurality of solar cells 40 are electrically connected in series and in parallel (series-parallel connection structure).

[0096] The solar cell module 1 has a plurality of solar cells 40 arranged at a distance from one another, and a plurality of connection members 60 that electrically connect the plurality of solar cells 40. The solar cell module 1 has a structure in which the plurality of solar cells 40 and the like are provided between a light-transmitting substrate and a protective member, and are sealed with a light-transmitting resin layer.

[0097] The plurality of solar cells 40 are arranged in a matrix along the first direction D1 and the second direction D2. Each solar cell 40 has a flat plate shape, and in the embodiment shown in Fig. 14, for example, a divided cell is used, which is obtained by dividing a solar cell substrate having a size of approximately 156 mm square into two. Therefore, the solar cell 10 has a size of approximately 156 mm x 78 mm square. The solar cell module 1 has a structure in which the plurality of solar cells 40 and the like are provided between a light-transmitting substrate and a protective member and sealed with a light-transmitting resin layer.

[0098] Here, a divided cell refers to a small cell obtained by dividing a standard-sized cell (a cell equivalent to one solar cell wafer, also called a full cell). Examples of divided cells include a standard-sized cell divided in half (a half cell). Divided cells can reduce the current value per cell (by half in the case of a half cell), thereby enabling a corresponding reduction in power loss in the solar cell module 1. In the illustrated embodiment, the solar cell 40 is a half cell. While the solar cell 40 is a half cell obtained by dividing a standard-sized cell in half in the illustrated embodiment, it may also be a divided cell divided into one-third or one-quarter. The divided cell may also have a substantially square shape obtained by further dividing a half cell in half.

[0099] As shown in Figures 11(a) and 11(b), solar cell 40 is a flat photovoltaic element that generates power when irradiated with light, and includes a front electrode 41 and a back electrode 42. The front electrode 41 is provided on the light-receiving surface side of solar cell 40 and includes, for example, a busbar electrode and a finger electrode. The busbar electrode of front electrode 41 is provided linearly in a first direction D1 on the light-receiving surface of solar cell 40. The finger electrode is formed linearly from the busbar electrode in a second direction D2.

[0100] The back surface electrode 42 is provided opposite the front surface electrode 41 and includes, for example, bus bar electrodes and finger electrodes. The bus bar electrodes of the back surface electrode 42 are provided linearly in the first direction D1 on the back surface of the solar cell 40. The finger electrodes are formed linearly in the second direction D2 from the bus bar electrodes.

[0101] A plurality of pads 43 are provided on the busbar electrodes (collecting electrodes) to improve adhesion with wiring materials such as wires and to reduce contact resistance for connection, and end pads 44 are also provided on the ends of the solar cell 40 in the first direction D1. These pads 43 and end pads 44 have a relatively wide width and can serve as regions for attaching and fixing second wiring portions 62, which will be described later, and the like.

[0102] The connection member 60 that connects adjacent solar cells 40 includes a first wiring portion 61 extending in the first direction D1 and a second wiring portion 62 extending in the second direction D2. The first wiring portion 61 connects in series one solar cell 40 and another solar cell 40 that are adjacently arranged along the first direction D1. The second wiring portion 62 connects in parallel one solar cell 40 and another solar cell 40 that are adjacently arranged along the second direction D2.

[0103] The first wiring portion 61 is a wire-shaped (or linear) conductive member. For example, the first wiring portion 61 is a wire-shaped wiring material (interconnector wire) having a configuration in which the outer surface of a wire having a substantially circular cross section is coated with a conductive adhesive or solder. The material of the wire is not particularly limited, but a metal such as copper can be used.

[0104] The first wiring portion 61 connects the front surface electrode 41 of one solar cell 40 aligned in the first direction D1 to the back surface electrode 42 of the other solar cell 40. The first wiring portion 61 is connected to the back surface electrode 42 of the solar cell 40 by welding or via a conductive adhesive. As a result, the solar cells 40 arranged adjacent to each other in the first direction D1 are electrically connected in series by the first wiring portion 61 arranged along the first direction D1.

[0105] The solar cell units 40 arranged adjacent to each other in the second direction D2 are electrically connected to each other by second wiring portions 62 extending along the second direction D2. The second wiring portions 62 are also made of a wire-like (or linear) conductive member, similar to the first wiring portions 61. For example, the second wiring portions 62 are made of a wire-like conductive member (interconnector wire) having a configuration in which the outer surface of a conductive wire having a substantially circular cross section is coated with a conductive adhesive or solder.

[0106] The cross-sectional shape of the conductive member that is the second wiring portion 62 is preferably at least partially circular or elliptical. The diameter of the conductive member is preferably about 0.30 to 0.35 mm. The material of the conductive member wire is not particularly limited, but metals such as copper can be used.

[0107] The second wiring portion 62 is disposed on the back surface side of the solar cell 40, intersects with the first wiring portion 61 connected to the back surface electrode 42, and is connected to the first wiring portion 61. The second wiring portion 62 is also electrically connected to the first wiring portion 61 by welding or via a conductive adhesive. By such second wiring portion 62, the solar cell cells 40 adjacent to each other in the second direction D2 are electrically connected in parallel.

[0108] The welding between the first wiring portion 61 and the back surface electrode 42, and the welding between the first wiring portion 61 and the second wiring portion 62 can be performed by joining (welding and fixing) using an ultrasonic welding method, a laser welding method, etc. The conductive adhesive can be solder, a conductive solder resin, a conductive paste, etc., and among these, solder is particularly preferable.

[0109] The solar cell module 1 is configured by electrically connecting two solar cell string units 103, each having a plurality of solar cells 40 in a series-parallel connection structure, by a bus bar serving as a transition wiring. In the illustrated embodiment, as shown in Fig. 14 , at the lower end of the first wiring portion 61 in the first direction D1 in the drawing, the first wiring portion 61 is electrically connected to a first bus bar 71 extending in the second direction D2. At the upper end of the first wiring portion 61 in the first direction D1 in the drawing, the first wiring portion 61 is electrically connected to a second bus bar 72 extending in the second direction D2. The second bus bar 72 serves as a transition wiring and electrically connects one solar cell string unit 103 to the other solar cell string unit 103 in series.

[0110] In the solar cell module 1, the first bus bar 71 is provided to extract power from a solar cell string including a plurality of (six in this case) solar cells 40 arranged along the first direction D1. The second bus bar 72 connects the negative electrode of one solar cell string unit 103 to the positive electrode of the other solar cell string unit 103.

[0111] 14 includes two solar cell string units 103 connected in series. Each solar cell string unit 103 has six solar cells 40 arranged along the first direction D1 and a plurality of solar cell strings electrically connected in series by connection members 60 (first wiring portions 61).

[0112] In this case, three solar cell strings are provided in one solar cell string unit 103. In each solar cell string unit 103, three solar cells 40 are arranged adjacent to each other in the second direction D2, and the solar cells 40 are electrically connected in parallel by connection members 60 (second wiring portions 62). As a result, in each solar cell string unit 103, the solar cell module 1 has a connection structure that includes both a plurality of solar cell cells 40 connected in series and a plurality of solar cell cells 40 connected in parallel.

[0113] As described above, in the solar cell module 1 according to this embodiment, the solar cell string unit 103 can be configured to have both a series-connected solar cell 40 and a parallel-connected solar cell 40. Therefore, even if a solar cell 40 enters a reverse bias state due to partial shading, current flows through a parallel-connected circuit that bypasses that solar cell 40, allowing the solar cell module to stabilize its power generation. Furthermore, the solar cell module 1 according to this embodiment has two solar cell string units 103 connected in series. Therefore, a higher voltage can be achieved compared to a solar cell module including only one solar cell string unit. Furthermore, by providing multiple solar cell string units 103 in one solar cell module 1 and connecting them in series, desired solar cell module characteristics can be achieved.

[0114] Fifth Embodiment FIG. 15 is a plan view schematically illustrating a solar cell module 1 according to a fifth embodiment of the present disclosure.

[0115] In the present disclosure, the solar cell module 1 including the double-sided electrode type solar cell 40 having the surface electrode 41 and the back electrode 42 shown in embodiment 3 can also be configured to have a series-parallel connection structure as shown in embodiment 2.

[0116] 15 , the plurality of solar cells 40 are arranged in a matrix along the first direction D1 and the second direction D2. The first wiring portion 61 of the connection member 60 connects in series one solar cell 40 and another solar cell 40 that are adjacently arranged along the first direction D1. The second wiring portion 62 connects in parallel one solar cell 40 and another solar cell 40 that are adjacently arranged along the second direction D2.

[0117] The solar cell module 1 according to the exemplary embodiment includes three solar cell string units 104, each including a solar cell string made up of solar cell cells 40 connected in this manner. The second bus bar 72 is disposed across the two solar cell string units 104, connecting one solar cell string unit 104 to the other solar cell string unit 104 in series. As shown in Fig. 15 , the second bus bar 72 is disposed as a crossover wiring so as to connect the negative pole of one solar cell string unit 104 to the positive pole of the other solar cell string unit 104. The first bus bar 71 is connected to the start and end of the three solar cell string units 104 connected in series, so as to extract power.

[0118] The solar cell module 1 according to this embodiment also includes solar cell cells 40 having both series and parallel connection configurations in each of the multiple solar cell string units 104, and can be provided with both series and parallel connection structures. This makes it possible to solve the problem of reduced power generation due to partial shading, and increase the effective power generation amount. Furthermore, the solar cell module 1 according to this embodiment has a configuration in which three solar cell string units 104 are connected in series, so it can increase the voltage.

[0119] Fig. 16 is a plan view showing a solar cell module 90c as a comparative example. As shown in the figure, the three solar cell string units 900 constituting the solar cell module 90c include wiring members 901 corresponding to the first wiring members 61, but do not include wiring members corresponding to the second wiring members 62 shown in Fig. 15, and the solar cell cells 40 in Fig. 16 are not connected in parallel on a cell-by-cell basis.

[0120] Consider a solar cell module 90c shown in Figure 16, which includes multiple solar cell string units 900 and solar cells 40 connected in series but not in parallel. In this case, if partial shading causes a solar cell to be in a reverse bias state, a mismatch in the current flowing through the solar cells occurs, and the current value of the solar cell module as a whole is limited by the current value of the solar cell with the lowest current through the series-connected circuit. As a result, power cannot be extracted efficiently, and output power decreases.

[0121] In contrast, the solar cell module 1 according to this embodiment shown in FIG. 15 only experiences a power drop in the solar cell that is partially shaded, so that the drop in the amount of power generated by the solar cell module 1 can be suppressed, and the amount of power generated can be stabilized.

[0122] As described above, according to the solar cell module according to the above-described embodiment of the present disclosure, it is possible to suppress the influence of a decrease in power generation amount due to partial shading, and to increase the substantial power generation amount.

[0123] In the solar cell module 1 according to the present disclosure, the connection member 60 connecting the plurality of solar cells 40 is not limited to the configuration shown in the above embodiment, and the plurality of solar cells 40 may be connected using a wiring sheet formed by providing a connection member including a first wiring portion and a second wiring portion on an insulating substrate. Furthermore, the solar cell module and the solar cell string unit and solar cell string included therein are not limited to the above configuration, and can have various other configurations. For example, the solar cell module can also be suitably implemented as a solar cell module with a curved surface shape.

[0124] Furthermore, the types of solar cells included in the solar cell module are not limited to those illustrated, and cells made of various semiconductor materials, such as polycrystalline semiconductors and compound semiconductors, can be used. Furthermore, the solar cell is not limited to the standard-sized cells illustrated (cells equivalent to one solar cell wafer, also referred to as full cells), but may also be cells obtained by dividing a standard-sized cell in half (half cells) or divided cells, such as cells divided into one-third or one-quarter. The solar cell module can be configured with multiple solar cell cells arranged in various ways in the first direction D1 and the second direction D2. The light-receiving surface protective member included in the solar cell module can be selected from transparent glass or a resin material, and the back surface protective member can be selected from a back sheet, transparent glass, or a resin material.

[0125] The present invention can be embodied in various other forms without departing from its spirit or essential features. Therefore, the above-described embodiments are merely illustrative in all respects and should not be interpreted as limiting. The scope of the present invention is defined by the claims and is not limited to the text of the specification. Furthermore, all modifications and variations within the equivalent range of the claims are within the scope of the present invention.

[0126] This application claims priority based on Japanese Patent Application No. 2023-215205, filed in Japan on December 20, 2023, the entire contents of which are incorporated herein by reference.

[0127] REFERENCE SIGNS LIST 1 Solar cell module 100, 101, 102, 103, 104 Solar cell string unit 11, 11a, 12 Solar cell string 20, 40 Solar cell 21 Semiconductor substrate 231 First conductivity type cell electrode 232 Second conductivity type cell electrode 241 First collector electrode 242 Second collector electrode 30, 50 Inter-cell wiring (connecting member) 31, 51 First wiring portion 32, 52 Second wiring portion 33 Opening 34 Jumper wiring 41 Surface electrode 42 Back electrode 60 Connecting member 61 First wiring portion 62 Second wiring portion 71 First bus bar 72 Second bus bar D1 First direction D2 Second direction

Claims

1. A solar cell module comprising a plurality of solar cell string units, wherein the solar cell string units include a plurality of solar cell strings formed by electrically connecting a plurality of solar cells arranged along a first direction, the plurality of solar cell strings are arranged and connected in parallel in a second direction intersecting the first direction, the plurality of solar cell strings adjacent to each other in the first direction are electrically connected in series, and the plurality of solar cell string units adjacent to each other in the second direction are electrically connected in parallel, and the plurality of solar cell string units are electrically connected in series.

2. A solar cell module as described in claim 1, wherein the solar cell string comprises a plurality of the solar cells arranged along the first direction electrically connected by a connection member, the connection member comprising a first wiring portion extending in the first direction and a second wiring portion connected to the first wiring portion and extending in a second direction intersecting the first direction, and the solar cell string unit comprises a plurality of the solar cell strings adjacent to each other in the first direction connected by the connection member and electrically connected in series, and a plurality of the solar cell strings adjacent to each other in the second direction connected by the connection member and electrically connected in parallel.

3. A solar cell module according to claim 2, characterized in that the connection member is disposed at least between the solar cell cells adjacent to each other in the first direction.

4. A solar cell module as described in claim 3, wherein the solar cell is a back electrode type solar cell having an electrode on one side of a semiconductor substrate, the electrodes including a first conductivity type cell electrode and a second conductivity type cell electrode, a first collector electrode connected to the first conductivity type cell electrode is provided on one side of the first direction of the semiconductor substrate, and a second collector electrode connected to the second conductivity type cell electrode is provided on the other side of the first direction, the first wiring portion of the connecting member extending in one side of the first direction is connected to the first collector electrode of one of two solar cells adjacent in the first direction, and the first wiring portion extending in the other side of the first direction is connected to the second collector electrode of the other solar cell.

5. A solar cell module as described in claim 3, wherein the solar cell is a double-sided electrode type solar cell having, as electrodes, a surface electrode on the light-receiving surface side and a back electrode on the surface opposite the light-receiving surface, and the first wiring portion extending in one direction of the first direction of the connecting member is connected to the surface electrode of one of two solar cells adjacent in the first direction, and the first wiring portion extending in the other direction of the first direction is connected to the back electrode of the other solar cell.

6. A solar cell module as described in claim 2, wherein the solar cell is a double-sided electrode type solar cell having, as electrodes, a front electrode on the light-receiving surface side and a back electrode on the surface opposite the light-receiving surface, the first wiring portion of the connection member connects the front electrode of one of the solar cells and the back electrode of the other solar cell adjacent in the first direction, and the second wiring portion of the connection member is disposed on the back side of the solar cell, intersects with the first wiring portion connected to the back electrode, and is connected to the first wiring portion.

7. A solar cell module according to claim 1, characterized in that the number of solar cell string units connected in series is two or more, and the number of solar cell strings included in the solar cell string unit is three or more.

8. A solar cell module according to claim 1, characterized in that the number of solar cell string units connected in series is three or more, and the number of solar cell strings included in said solar cell string unit is two or more.

9. A method for manufacturing a solar cell module according to any one of claims 1 to 8, comprising the steps of: forming the solar cell string unit; and connecting a plurality of the solar cell string units in series.

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