SOLAR CELL MODULE

A solar cell module includes a first solar cell, a second solar cell and an electrically connecting member. The first solar cell has a first connecting side having at least one first protruding portion and at least one first recess portion that are adjacent to each other. The second solar cell has a second connecting side having at least one second protruding portion and at least one second recess portion that are adjacent to each other. The shape of the first protruding portion matches the shape of the second recess portion while the shape of the first recess portion matches the shape of the second protruding portion. The electrically connecting member electrically connects the first upper electrode layer of the first solar cell and the second lower electrode layer of the second solar cell.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 102141349 filed in Taiwan, R.O.C. on 2013 Nov. 13, the entire contents of which are hereby incorporated by reference.

TECHNICAL FIELD

The disclosure relates to a solar cell module.

BACKGROUND

In current solar cell technology, a photoelectric conversion active layer or an absorber is used for converting light energy, from the sun for example, into electrical energy. A solar cell has an upper electrode layer and a lower electrode layer on the upper surface and the lower surface of the absorber, respectively. When receiving light, the absorber separates electric charges to the upper electrode layer and the lower electrode layer, thereby generating voltages and currents. The photo-generated voltages and currents can vary due to different material properties of the absorbers, as well as different light receiving areas and illuminating intensity of the solar cells. Under the same illuminating intensity, the photocurrent increases as the light receiving area rises. The output voltages, however, cannot be increased by increasing the light receiving area. The electrical power tends to be wasted under the circumstance of lower voltage with high current. Hence, isolated solar cells are interconnected in series to raise the output voltage of a solar cell module, thereby avoiding the waste of electrical power. In addition, these isolated solar cells can be connected in parallel for raising the current if needed.

Typically, solar cells are cut into rectangular shapes. For the serial interconnection of the first solar cell and the second solar cell, manufactures may arrange them next to each other (namely, side by side) with their upper electrode layer facing up, and using a conductive material to electrically connect the upper electrode layer of the first solar cell with the lower electrode layer of the second solar cell. The manufactures usually make the conductive material electrically connect to the upper electrode layer of the first solar cell, and then make the conductive material run through the gap between the first solar cell and the second solar cell. Subsequently, the manufactures flip the first solar cell and the second solar cell to make their lower electrode layers face up, and making the conductive material in the gap electrically connect to the lower electrode layer of the second solar cell. However, there should be enough space for the solar cells to flip upside down, especially when there are many of them interconnected in series. Consequently, a method for interconnecting solar cells without flipping them was developed. In this method, manufactures made the upper electrode layer of the first solar cell and the lower electrode layer of the second solar cell face up before electrically connecting them with a conductive material with enough width for making the interconnection. Although this approach does not need to flip over the solar cells, it wastes a large amount of conductive materials. In addition, a larger area of the solar cell is blocked by the conductive material so that the conversion efficiency is worsened. Moreover, the alignment of the conductive material has to match the positions of the first and the second solar cells precisely to avoid poor electrical interconnection. This makes the manufacturing of the solar cell module difficult.

SUMMARY

A solar cell module comprises a first solar cell, a second solar cell and an electrically connecting member. The first solar cell comprises a first upper electrode layer, a first photoelectric conversion active layer and a first lower electrode layer. The first photoelectric conversion active layer is disposed between the first upper electrode layer and the first lower electrode layer, and the first solar cell has a first connecting side having at least one first protruding portion and at least one first recess portion that are adjacent to each other. The second solar cell comprises a second upper electrode layer, a second photoelectric conversion active layer and a second lower electrode layer. The second photoelectric conversion active layer is disposed between the second upper electrode layer and the second lower electrode layer. The second solar cell has a second connecting side having at least one second protruding portion and at least one second recess portion that are adjacent to each other. The second lower electrode layer of the second protruding portion has a first exposed section. The first solar cell is arranged next to the second solar cell, and the shape of the first protruding portion matches the shape of the second recess portion while the shape of the first recess portion matches the shape of the second protruding portion. The electrically connecting member is disposed on the first upper electrode layer of the first protruding portion and the first exposed section of the second lower electrode layer of the second protruding portion. The electrically connecting member electrically connects the first upper electrode layer and the second lower electrode layer.

DETAILED DESCRIPTION

FIG. 1is a perspective view of a solar cell module according to an embodiment of the disclosure;FIG. 2Ais an exploded view ofFIG. 1;FIG. 2Bis a side view ofFIG. 2A.

As seen inFIG. 1,FIG. 2AandFIG. 2B, in this embodiment, solar cell module1comprises a first solar cell11, a second solar cell12, an electrically connecting member13, a back plate14, a plurality of adhesive layers15,15a,15band a cover plate16.

The first solar cell11comprises a first substrate110, a first lower electrode layer111, a first photoelectric conversion active layer112, a first upper electrode layer113, a first wire114aand a plurality of first charge collecting fingers115. As shown from the bottom to the top in the figures, the first lower electrode layer111is disposed on the first substrate110, the first photoelectric conversion active layer112is disposed on the first lower electrode layer111, the first upper electrode layer113is disposed on the first photoelectric conversion active layer112, and the first charge collecting finger115is disposed on the first upper electrode layer113. Therefore, the first lower electrode layer111is located between the first substrate110and the first photoelectric conversion active layer112, while the first photoelectric conversion active layer112is located between the first lower electrode layer111and the first upper electrode layer113. The material of the first substrate110can be a plastic substrate (e.g. polyimide, PI) or a metal substrate (e.g., stainless steel foil, aluminum foil or titanium foil). The material of the first lower electrode layer111can be a metal conductive layer such as molybdenum (Mo), aluminum (Al), copper (Cu), chromium (Cr). The material of the first photoelectric conversion active layer112can be a thin photovoltaic film such as copper indium gallium diselenide (CIGS), amorphous silicon (a-Si), cadmium telluride (CdTe). The material of the first upper electrode layer113can be a thin transparent conductive oxide film such as aluminum doped zinc oxide (AZO), boron doped zinc oxide (BZO), indium tin oxide (ITO). The material of the first charge collecting finger115can be silver or copper or aluminum/nickel. The first lower electrode layer111, the first photoelectric conversion active layer112and the first upper electrode layer113can be stacked as a thin film solar cell, and the total width is about 0.5 μm to 5 μm.

The first solar cell11has a first connecting side11aand a third connecting side11bopposite to the first connecting side11a. The first connecting side11ahas at least one first protruding portion11a1and at least one first recess portion11a2that are adjacent to each other. The third connecting side11bhas at least one third protruding portion11b1and at least one third recess portion11b2that are adjacent to each other. In this embodiment, both the number of the first protruding portion11a1and that of the third recess portion11b2are one, but they are not limited thereto. In this embodiment, both the number of the first recess portion11a2and that of the third protruding portion11b1are also two, but they are not limited thereto. In this embodiment, the first protruding portion11a1, the first recess portion11a2, the third protruding portion11b1and the third recess portion11b2are all trapezoid shapes, but the disclosure is not limited thereto. Moreover, the shapes of them may be the same or different from each other.

The first wire114acan be disposed on the first upper electrode layer113and the first charge collecting finger115by screen printing, attachment or sputtering, and the first wire114ais next to the first connecting side11a. When light (e.g., sunlight) enters into the first solar cell11, the first photoelectric conversion active layer112generates electric charges. Then, these electric charges are collected and transferred to the first wire114avia the first upper electrode layer113, and the first charge collecting finger115. The material of the first wire114amay be electrically conductive bonding material such as solder, silver paste, copper paste, anisotropic conductive film (ACF). The first lower electrode layer111on the third protruding portion11b1has a second exposed section111a. The first electrode layer113and the first photoelectric conversion active layer112do not cover the second exposed section111aof the first lower electrode layer111. The first solar cell11further comprises a third wire114bdisposed on the second exposed section111aof the first lower electrode layer111. When receiving the light, the first photoelectric conversion active layer112generates the other type of electric charges and these electric charges can be guided to the third wire114bby the first lower electrode layer111. The conductive material of the third wire114bmay be the same or be different from that of the first wire114a.

The second solar cell12comprises a second substrate120, a second lower electrode layer121, a second photoelectric conversion active layer122, a second upper electrode layer113, a second wire124a, and a plurality of second charge collecting fingers125. As shown from bottom to top in the figures, the second lower electrode layer121is disposed on the second substrate120, the second photoelectric conversion active layer122is disposed on the second lower electrode layer121, the second upper electrode layer123is disposed on the second photoelectric conversion active layer122, and the first charge collecting finger125is disposed on the second upper electrode layer123. Therefore, the second lower electrode layer121is located between the second substrate120and the second photoelectric conversion active layer122, while the second photoelectric conversion active layer122is located between the second lower electrode layer121and the second upper electrode layer123. The material of the second substrate120can be plastic substrate (e.g. polyimide, PI) or metal substrate (e.g. stainless steel foil, aluminum foil or titanium foil). The material of the second lower electrode layer121can be metal conductive layer such as molybdenum (Mo), aluminum (Al), copper (Cu), chromium (Cr). The material of the second photoelectric conversion active layer122can be thin photovoltaic film such as copper indium gallium diselenide (CIGS), amorphous silicon (a-Si), cadmium telluride (CdTe). The material of the upper electrode layer113can be the conductive thin film such as aluminum doped zinc oxide (AZO), boron doped zinc oxide (BZO), indium tin oxide (ITO). The material of the first charge collecting finger125can be silver or copper or aluminum/nickel. The second lower electrode layer121, the second photoelectric conversion active layer122and the second upper electrode layer123can be stacked as a thin film solar cell, and the total width is about 0.5 μm to 5 μm.

The second solar cell12has a second connecting side12aand a fourth connecting side12bopposite to the second connecting side12a. The second connecting side12ahas at least one second protruding portion12a1and at least one second recess portion12a2that are adjacent to each other. The fourth connecting side12bhas at least one fourth protruding portion12b1and at least one fourth recess portion12b2adjacent to each other. In this embodiment, both the number of the second protruding portion12a1and that of the fourth recess portion12b2are one, but they are not limited thereto. In this embodiment, both the number of the second recess portion12a2and that of the fourth protruding portion12b1are two, but they are not limited thereto. In this embodiment, the second protruding portion12a1, the second recess portion12a2, the fourth protruding portion12b1and the fourth recess portion12b2are all trapezoid shapes, but the disclosure is not limited thereto. Moreover, the shapes of them may be the same or different from each other.

The second lower electrode layer121on the second protruding portion12a1has a first exposed section121a. The second electrode layer123and the second photoelectric conversion active layer122do not cover the first exposed section121aof the first lower electrode layer111. The second wire124acan be disposed on the first exposed section121aof the second lower electrode layer121and by screen printing, attachment or sputtering. The material of the second wire124amay be electrically conductive bonding material such as solder, silver paste, copper paste, anisotropic conductive film (ACF). The second solar cell12further comprises a fourth wire124b. The fourth wire124bcan be disposed on the second upper electrode layer123and the second charge collecting finger125, by screen printing, attachment or sputtering, and the fourth wire124bis next to the fourth connecting side14b. When the light enters into the second solar cell12, the second photoelectric conversion active layer122generates electric charges. Then, these electric charges are collected to the second wire124avia the second upper electrode layer123and the second charge collecting finger125. The conductive material of the fourth wire124bmay be the same or be different from that of the second wire124a.

The first solar cell11and the second solar cell12are arranged next to each other along the positive and negative x direction, and are separated by a distance D1 along the positive and negative x direction. The first connecting side11afaces the positive x direction, while the second connecting side12afaces the negative x direction. Therefore, the first protruding portion11a1protrudes towards the positive x direction, the first recess portion11a2recesses towards the negative x direction; the second protruding portion12a1protrudes towards the negative x direction, and the second recess portion12a2recesses towards the positive x direction. The first connecting side11aand the second connecting side12aare spaced apart by a distance D1. The first protruding portion11a1matches the second recess portion12a2, while the first recess portion11a2matches the second protruding portion12a1. Specifically, the first connecting side11aand the second connecting side12aare similar in terms of their appearance. The first protruding portion11a1is inserted in the first recess portion11a2. The first exposed section121aof the first upper electrode layer113and the second lower electrode layer121both face towards the positive z direction, and at least one plane P, parallel to the positive and negative z direction, can pass through the first exposed section121aof the first upper electrode layer113and the second lower electrode layer121. Furthermore, the plane P can pass through the first wire114aand the second wire124aof the first protruding portion11a1. The difference of the height between the first exposed section121aof the first upper electrode layer113and the second lower electrode layer121along the positive and negative z direction is less than 0.5 μm to 5 μm.

The electrically connecting member13is disposed both on the first upper electrode layer113of the first protruding portion11a1and the first exposed section121aof the second lower electrode layer121as well as being electrically connected to the first charge collecting finger115and the first upper electrode layer113via the first wire114a. Then, the electrically connecting member13is electrically interconnected to the second lower electrode layer121via the second wire124a. The electrically connecting member13can be attached to the first wire114aand the second wire124aalong the plane P. That is, viewing from the positive z to negative z direction, the electrically connecting member13is a conducting ribbon or a conducting wire extending along the positive and negative y direction. Thereby, even though the electrically connecting member13is narrow (e.g. the width thereof is only 1.5 mm or less), it can connect the first solar cell11and the second solar cell12in series. The margin of error regarding the matching between the first solar cell11and the second solar cell12can be the width of the first protruding portion11a1or of the second protruding portion12a1along the positive and negative x direction. Thereby, this makes the manufacturing of the solar cell module1easier. Since the width of the electrically connecting member13is narrow, the shading area of the first solar cell11and the second solar cell12is smaller. As a result, the use of the electrically connecting member13is reduced so the cost thereof decreases. Moreover, the light receiving areas of the first solar cell11and the second solar cell12are increased.

Similarly, if needed, the third connecting side11bof the first solar cell11can be electrically interconnected to other solar cell(s) along the negative x direction by applying this method. The fourth connecting side12bof the second solar cell12can be electrically interconnected to other solar cell(s) along the positive x direction by applying this method.

Although the first exposed section121aof the first upper electrode layer113and the first exposed section121aof the second lower electrode layer121have different heights, the difference thereof is less than 0.5 μm to 5 μm. This difference of height is much less than the thickness of the electrically connecting member13, from 100 μm to 200 μm. Hence, when electrically interconnecting the first upper electrode layer113of the electrically connecting member13and the second lower electrode layer121of the electrically connecting member13, the difference of height, between the first upper electrode layer113and the first exposed section121a, can be ignored. It should be noted that the drawing scales ofFIG. 1,FIG. 2AandFIG. 2Bare for reference only and they may not reflect the scale of the product perfectly.

As seen inFIG. 1andFIG. 2B, the first solar cell11and the second solar cell12are attached to the back plate14by the adhesive layer15b. The cover plate16is attached to all the first solar cell11, the second solar cell12and the electrically connecting member13by the adhesive layer15a. The adhesive layers15aand15bcan infiltrate the gap between the first solar cell11and the second solar cell12, thereby being stuck to each other. When the materials of the adhesive layers15aand15bare the same, the adhesive layers15aand15bcan form the adhesive layer15together inFIG. 1, after being attached to each other. The material of the transparent or non-transparent back plate14can be selected from a group consisting of ethylene tetrafluoroethylene (ETFE), polyethylene terephthalate (PET), polyethylene N-phthalate (PEN), polyimide (PI), Tefzel, or Tedlar, plastic substrates, glass substrates, other metal foils (e.g. aluminum foil) and combinations thereof. The material of the transparent cover plate16may be selected from a group consisting of ethylene tetrafluoroethylene (ETFE), polyethylene terephthalate (PET), polyethylene N-Phthalate (PEN), polyimide (PI), Tefzel, or Tedlar, plastic substrates, glass substrates, and the combinations thereof. The material of the adhesive layer15, the adhesive layer15aand the adhesive layer15bmay be adhesive material such as ethylene vinyl acetate (EVA) or poly vinyl butyral (PVB).

In this embodiment, the shapes of the first solar cell11and the second solar cell12are substantially the same. In detail, the shapes of the first connecting side11aand the third connecting side11bare the same, the shapes of the second connecting side12aand the third connecting side11bare the same, but the disclosure is not limited thereto. In other embodiments, the shapes of the first connecting side11aand the third connecting side11bare different; the shapes of the second connecting side12aand the third connecting side11bare different.

FIGS. 3 to 9are top views of assembly processes of the solar cell modules1aand1b. In this embodiment, the first solar cell11and the second solar cell12are the same for illustrating the assembly processes of the solar cell modules1aand1b. The solar cell modules1aand1bhave more first solar cell11, arranged next to each other and electrically interconnected to each other, than the solar cell module1.

As seen inFIG. 3with the above description ofFIG. 1andFIG. 2A, the first lower electrode layer111is disposed on the first substrate110, the first photoelectric conversion active layer112is disposed on the first lower electrode layer111, the first upper electrode layer113is disposed on the first photoelectric conversion active layer112, the first charge collecting finger115is disposed on the first upper electrode layer113. Then, a single unit of the first solar cell11is cut from the first substrate110, the first lower electrode layer111, the first photoelectric conversion active layer112, the first upper electrode layer113, and the first charge collecting finger115. Multiple single units of the first solar cell11can be cut from the first substrate110, the first lower electrode layer111, the first photoelectric conversion active layer112, the first upper electrode layer113, and the first charge collecting finger115. Additionally, the first connecting side11ais formed along the positive x direction when cutting the single unit of the first solar cell11, while the third connecting side11bis formed along the negative x direction. The first connecting side11ahas the first protruding portion11a1and the first recess portion11a2. The third connecting side11bhas the third protruding portion11b1and the third recess portion11b2.

As seen inFIG. 4in view ofFIG. 1andFIG. 2A, at the position of the third protruding portion11b1, the first charge collecting finger115, the first upper electrode layer113and the first photoelectric conversion active layer112are removed by grinding or scribing, so that the first connecting side11aof the first lower electrode layer111is exposed. Subsequently, the first wire114ais attached to the first upper electrode layer113and the first charge collecting finger115by the screen printing, attachment, or sputtering, and the first wire114ais next to the first connecting side11a. The third connecting side11bis disposed on the first connecting side11aof the first lower electrode layer111by the screen printing, attachment or sputtering. As a result, the manufacturing of the first solar cell11is finished.

As seen inFIG. 2B,FIG. 4andFIG. 5, the manufacturers can arrange the first solar cell11on the back plate14based on the output voltage and the output current. The first solar cell11can be attached to the back plate14by the adhesive layer15b. In this embodiment, the first solar cells11are arranged as three rows along the positive and negative x directions and two rows along the positive and negative y directions. The first solar cell11along the positive and negative x directions are separated by a distance D1, while the first solar cell11along the positive and negative y directions are separated by a distance D2. These distances D1 and D2 prevent each the first solar cell11from being electrically interconnected to each other. These distances D1 and D2 can be the same or be different from each other. The first protruding portion11a1of each the first solar cell11corresponds to the third recess portion11b2next to the first solar cell11, while the first recess portion11a2corresponds to the third protruding portion11b1next to the first solar cell11.

As seen inFIG. 1,FIG. 2A,FIG. 2BandFIG. 6, the electrically connecting member13aand the electrically connecting member130extend along the positive and negative y directions. The electrically connecting member13acan interconnect the first solar cell11along the positive and negative x directions in series via the first protruding portion11a1and the third protruding portion11b1. The electrically connecting member13aand the electrically connecting member130can extend along the positive and negative y directions and interconnect to the first solar cell11along the positive and negative y directions in parallel. Subsequently, the cover plate16is attached to the first solar cell11by the adhesive layer15aand the package of the solar cell module1ais finished by lamination process. The equivalent circuit of the solar cell module1ais shown inFIG. 7. When each first solar cell11provides a voltage V and a current A, and the loss is ignored, the solar cell module1acan output 3V and 2A, approximately.

As seen inFIG. 1,FIG. 2A, andFIG. 8, the electrically connecting member13a, the electrically connecting member13band the electrically connecting member130all extend along the positive and negative y directions, while the electrically connecting member13aand the electrically connecting member13bare cut to be divided from each other so they are not electrically connected. The electrically connecting member13aand the electrically connecting member13bcan electrically interconnect the first protruding portion11a1and the third protruding portion11b1, so that the first solar cells11are interconnected along the positive and negative x directions in series. The electrically connecting member130can interconnect the first solar cells11along the positive and negative y directions in parallel by extending itself along the positive and negative y directions. Then, the cover plate16is attached to the first solar cell11via the adhesive layer15a, and the package of the solar cell module1bis finished by lamination process. The equivalent circuit of the solar cell module1bis shown inFIG. 9. When each first solar cell11provides a voltage V and a current A, and the loss is ignored, the solar cell module1acan output 3V and 2A, approximately.

FIG. 10is a top view of a solar cell module according to another embodiment of the disclosure. As seen inFIG. 10, the solar cell module2of this embodiment is similar to the solar cell module1. Nevertheless, in this embodiment, the first solar cell21has the first connecting side21aand the third connecting side21bthat are opposite to each other, while the second solar cell has the second connecting side22aand the fourth connecting side22bthat are opposite to each other. The first connecting side21ahas a first protruding portion21a1and a first recess portion21a2. The third connecting side21bmay not have the protruding portion or the recess portion. The second connecting side22ahas a second protruding portion22a1and a second recess portion22a2. The fourth connecting side22bmay not have the protruding portion or the recess portion. The part of the first lower electrode layer211which is adjacent to the third connecting side21bis exposed, and the third wire214bis disposed on the first lower electrode layer211. The fourth wire224bis disposed both on the second upper electrode layer223and the second charge collecting finger225, while the fourth wire224bis next to the fourth connecting side22b. Thereby, the manufacturing of the solar cell2can apply the example of the first solar cell21or the example of the second solar cell based on the requirements, so the configuration of the solar cell2is adjustable.

FIG. 11is a top view of a solar cell according to another embodiment of the disclosure. As seen inFIG. 11, the solar cell31of this embodiment is similar to the first solar cell11shown inFIG. 1,FIG. 2andFIG. 4. Nonetheless, in this embodiment, the solar cell31has the first connecting side31aand the third connecting side31bthat are opposite to each other. The first connecting side31afaces the negative x direction and has two first protruding portions31a1and one first recess portion31a2. The third connecting side31bfaces the positive x direction and has a third protruding portion31b1and two third recess portions31b2. The upper electrode layer313and the photoelectric conversion active layer (not shown due to being blocked by the upper electrode layer313) are located on the third protruding portion31b1of the third connecting side31b, and are removed by grinding or scribing, thereby exposing the second exposed area311a. Subsequently, the first wire314ais disposed on the upper electrode layers313and315, next to the first connecting side31a, by screen print, attachment or sputtering. The third wire314bis disposed on the second exposed area311aof the lower electrode layer by screen print, attachment or sputtering. Thereby, the manufacturing of the solar cell31is finished. The manufacturers can decide where to locate the second exposed area311aof the lower electrode layer, so that the arrangement of the solar cell31in the solar cell module is adjustable.

FIG. 12is a top view of a solar cell according to another embodiment of the disclosure. As seen inFIG. 12, the solar cell41of this embodiment is similar to the first solar cell11shown inFIG. 1,FIG. 2andFIG. 4. However, in this embodiment, the widths of the first wire414aand the third wire414bare defined as the widths along the positive and negative x directions. The width of the part414a1of the first wire414aon41a1is greater than that of the other part414a2. The width of the third wire414bis substantially the same as that of the part414a1of the first wire414aon41a1. Since the width of the part414a1of the first wire414aand the width of the third wire414bare wider, even multiple solar cells41do not match perfectly, a plane parallel to the positive and negative z directions can pass through the part414a1of the first wire414aand the third wire414b. The electrically connecting member13shown inFIG. 1andFIG. 2Acan extend along this plane and then can be electrically connected to the part414a1of the first wire414aand the third wire414b. Moreover, since the part414a1of the first wire414aand the third wire414bare wider, they have smaller resistances, thereby reducing the output electric loss of the solar cell41.

FIG. 13is a top view of a solar cell according to another embodiment of the disclosure. As seen inFIG. 13, the first solar cell51of this embodiment is similar to the first solar cell11shown inFIG. 1,FIG. 2andFIG. 4. However, in this embodiment, the first protruding portion51a1and the first recess portion51a2of the first connecting side51aand the third protruding portion51b1and the third recess portion51b2of the third connecting side51bare rectangular shapes. The number of the first protruding portions51a1is two, the number of the first recess portions51a2is three, the number of the third protruding portions51b1is three, and the number of the third recess portions51b2is two. The lengths of the first protruding portion51a1, the first recess portion51a2, the third protruding portion51b1and the third recess portion51b2are defined as the lengths along the positive and negative y directions. The length of the first protruding portion51a1is greater than that of the first recess portion51a2, while the length of the third protruding portion51b1is less than that of the third recess portion51b2. Thereby, the manufactures can adjust the shapes, numbers and lengths of the first protruding portion51a1, the first recess portion51a2,1b1and the third recess portion51b2, so that the arrangement of the first solar cell51can be modified easily.

FIG. 14is a top view of a semi-finished solar cell according to another embodiment of the disclosure. As seen inFIG. 14, the solar cell61of this embodiment is similar to the first solar cell11shown inFIG. 1,FIG. 2andFIG. 4. However, in this embodiment, the first protruding portion61a1and the first recess portion61a2of the first connecting side61aand the third protruding portion61b1and the third recess portion61b2of the third connecting side61bare isosceles triangle shapes.

FIG. 15is a top view of a semi-finished solar cell according to another embodiment of the disclosure. As seen inFIG. 15, the solar cell71of this embodiment is similar to the first solar cell11shown inFIG. 1,FIG. 2andFIG. 4. However, in this embodiment, the first protruding portion71a1and the first recess portion71a2of the first connecting side71aand the third protruding portion71b1and the third recess portion71b2of the third connecting side71bare non-isosceles triangle shapes.

FIG. 16is a top view of a semi-finished solar cell according to another embodiment of the disclosure. As seen inFIG. 16, the solar cell81of this embodiment is similar to the first solar cell11shown inFIG. 1,FIG. 2andFIG. 4. However, in this embodiment, the first connecting side81ahas the first protruding portion81a1and the first recess portion81a2, while the third connecting side81bhas the third protruding portion81b1and the third recess portion81b2. The shapes the first protruding portion81a1and the third recess portion81b2are pointed while the first recess portion81a2and the third protruding portion81b1are arc-shaped (or, chamfered).

FIG. 17is a top view of a semi-finished solar cell according to another embodiment of the disclosure. As seen inFIG. 17, the solar cell91of this embodiment is similar to the first solar cell11shown inFIG. 1,FIG. 2andFIG. 4. However, in this embodiment, the first protruding portion91a1and the first recess portion91a2of the first connecting side91aand the third protruding portion91b1and the third recess portion91b2of the third connecting side91bare arc-shaped.

Hence, the manufactures can adjust the shapes of the first protruding portions61a1,71a1,81a1and91a1, the first recess portions61a2,71a2,81a2and91a2, the third protruding portions61b1,71b1,81b1and91b1, and the third recess portions61b2,71b2,81b2and91b2, so that they can modify the arrangement of the solar cells61,71,81and91flexibly.

To sum up, in the solar cell module of the disclosure, since the first protruding portion and the second protruding portion are alternatively arranged, the electrically connecting member can electrically connect the first upper electrode layer of the first protruding portion and the second lower electrode layer of the second protruding portion. Thereby, multiple solar cells can be interconnected in series or in parallel, without flipping the solar cell module over. This makes the manufacturing of large solar cell module easier. Furthermore, electrically interconnecting the solar cell module in this way narrows the width of the electrically connecting member to the utmost, thereby reducing the cost of the material. Additionally, the narrower the electrically connecting members are, the lower the light-shading areas of the first solar cell and the second solar cell are. This increases the converting efficiency of the solar cell module.