TWI599057B - Solar cell and solar cell module - Google Patents

Description

Solar cell and solar cell module

The present invention relates to a solar cell and a solar cell module; in particular, to a solar cell capable of increasing the amount of light absorbed and a solar cell module provided with a light-expanding structure.

Generally, a solar cell module is formed by arranging a plurality of solar cell arrays on a substrate. Further, a structure for packaging is formed on each solar cell. Each of the solar cells basically includes a substrate that can be used to convert light energy into electrical energy, and top and bottom electrodes respectively formed on the top and bottom surfaces of the substrate. After the incident light is absorbed by the substrate and converted into electric energy, the electric energy is transmitted to the external device through an internal circuit formed between the top surface electrode and the bottom surface electrode, and then connected to a circuit circuit other than the external device.

In the above solar cells and solar cell modules, how to obtain a good amount of light absorption is very important, and how to efficiently extract the electric energy is equally important. Generally, the top surface electrode and the bottom surface electrode of the above solar cell are usually made of a metal material, thereby blocking part of the incident light and reducing the amount of light absorption. However, if the arrangement of the electrodes is sacrificed in order to obtain a large amount of light absorption, the electric take-out rate will be lowered.

According to the above, how to obtain a higher light absorption amount while maintaining the electric take-out rate is an important issue.

In particular, the present invention provides solar cells and their modules. Through the arrangement of different bus electrodes and extension electrodes on the solar cell, a large amount of light absorption and an electric extraction rate can be obtained. Moreover, when the solar cell module is formed, the light-expanding structure formed in the interior or surface of the packaging material, the light-transmitting member or the bus bar electrode can further increase the light absorption amount, thereby achieving better photoelectric conversion efficiency.

To achieve the above object, in one embodiment, the present invention provides a solar cell comprising a substrate and a top surface electrode, wherein the substrate can be used to convert light energy into electrical energy. The top surface electrode is formed on the top surface, and comprises at least one bus bar electrode and a plurality of extension electrodes extending from the bus bar electrode, wherein the bus bar electrodes and the extension electrodes have different directions. A first area and a second area are defined on both sides of the bus bar electrode, wherein the extended electrode areas in the first area are smaller than the extended electrode areas in the second area.

The solar cell described above further includes a bottom electrode formed on the bottom surface of the solar cell. Further, the width of the first region is less than or equal to 20 mm, and the width of the first region is equal to the width of the second region. Thereby, the amount of light absorbed by the first region is greater than the amount of light absorbed by the second region.

In an embodiment, the top surface electrode may include a triple bus bar electrode. A plurality of extension electrodes are respectively extended to each of the bus bar electrodes. First on each side of each bus electrode The region and each of the second regions, wherein the area of the extended electrodes in each of the first regions is smaller than the area of the extended electrodes in each of the second regions.

In the above solar cell, the width of each of the first regions is less than or equal to 20 mm, and the width of each of the first regions is equal to the width of each of the second regions.

In the above solar cell, the extension electrodes extending from the bus bar electrodes may be connected to each other in parallel, disconnected or staggered. Thereby, different electrical extraction rates can be obtained.

In one embodiment, the present invention further provides a solar cell module comprising a backing plate, a solar cell, a packaging material, and a light transmissive member. The solar cell is disposed on the backplane and includes a substrate and a top electrode. A top electrode is formed on the top surface of the substrate, and the substrate can be used to convert light energy into electrical energy. The top electrode includes at least one bus bar electrode and a plurality of extension electrodes extending from the bus bar electrode. The bus bar electrodes and the extension electrodes have different directions, and a first region and a second region are defined on both sides of the bus bar electrode, wherein the extended electrode area in the first region is smaller than the extended electrode area in the second region . The encapsulating material covers the solar cell. The light transmissive member is covered on the packaging material. A light-expanding structure is formed at the position of the corresponding bus bar electrode, and the light-expanding structure transmits the light-absorbing amount of the first region to be larger than the light-absorbing amount of the second region.

In the above solar cell module, the light-expanding structure may be formed by doping a plurality of particles in the encapsulating material or the light-transmitting member, and the position of the light-expanding structure corresponds to the position of the bus bar electrode. Alternatively, the light-expanding structure may be formed directly on the bus bar electrode by a ribbon, for example, it may be formed in a strip shape on the surface of the bus bar electrode by means of lamination or soldering. The light-expanding structure may also be formed on the surface of the light-transmitting member or the surface of the packaging material. The light-emitting structure can have multiple lenses or multiple The corner posts are arranged, and the surface of the light-emitting structure may be regular or irregular. The light-expanding structure may also form a roughened surface on the surface of the encapsulating material, the surface of the light transmissive member or the surface of the bus bar electrode.

In the above solar cell module, the light transmissive member may be a light transmissive glass or acrylic. The encapsulating material may be Ethylene-Vinyl Acetate Copolymer (EVA) or Poly-Vinyl Butyral (PVB).

In the above solar cell module, the top surface electrode may include three bus bar electrodes. A plurality of extension electrodes are respectively extended to each of the bus bar electrodes. Each of the first region and each of the second regions is defined on each of the bus bar electrodes, wherein the extended electrode area in each of the first regions is smaller than the extended electrode area in each of the second regions.

In the above solar cell, the width of each of the first regions is less than or equal to 20 mm, and the width of each of the first regions is equal to the width of each of the second regions.

In the above solar cell module, the extension electrodes extending from the bus bar electrodes may be connected to each other in parallel, disconnected or staggered. Thereby, different electrical extraction rates can be obtained. In addition, the solar cell module described above may include a plurality of solar cells arranged in an array on the backplane.

Thereby, the solar cell and the solar cell module can obtain a large amount of light absorption and an electric extraction rate, and the photoelectric conversion efficiency can be improved.

100‧‧‧ solar cells

110‧‧‧Substrate

111‧‧‧ top surface

120‧‧‧ top electrode

121‧‧‧ Bus bar electrode

122‧‧‧Extended electrode

200‧‧‧ solar cells

210‧‧‧Substrate

211‧‧‧ top surface

220‧‧‧ top electrode

221‧‧‧ bus bar electrode

300‧‧‧Solar battery module

310‧‧‧ Backplane

320‧‧‧Packaging materials

330‧‧‧Transparent parts

340‧‧‧Light-emitting structure

341‧‧‧ lens

342‧‧‧ corner column

A1‧‧‧ first area

A2‧‧‧Second area

L‧‧‧ incident light

L1‧‧‧scattered light

222‧‧‧Extended electrode

L2‧‧‧scattered light

Unit U1‧‧

Unit U2‧‧

P‧‧‧ particles

1 is a schematic structural view showing an embodiment of a solar cell according to the present invention; and FIG. 2 is a schematic structural view showing another embodiment of the solar cell according to FIG. 1; 3 is a schematic structural view showing an embodiment of a solar cell using a three-bus bar electrode in the present invention; FIG. 4 is a schematic structural view showing another embodiment of the solar cell according to FIG. 3; FIG. 5B is a schematic structural view showing another embodiment of a solar cell according to FIG. 5A; FIG. 6A is a schematic view showing the use of a triple current in the present invention; FIG. 6B is a schematic structural view showing another embodiment of a solar cell according to FIG. 6A; FIG. 7 is a schematic diagram showing a solar cell using a triple bus electrode in the present invention. FIG. 8 is a schematic structural view showing an embodiment of a solar cell using a triple bus electrode in the present invention; and FIG. 9 is a schematic structural view showing another embodiment of the solar cell according to FIG. 8; 10 is a schematic structural view of an embodiment of a solar cell module of the present invention; and FIG. 11 is a schematic structural view showing an embodiment of a solar cell module of the present invention; 12 is a schematic structural view of an embodiment of a solar cell module of the present invention; FIG. 13 is a schematic structural view showing an embodiment of a solar cell module of the present invention; and FIG. 14 is a view showing a solar cell module of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 15 is a schematic structural view showing an embodiment of a solar cell module of the present invention; Figure 16 is a block diagram showing an embodiment of a solar cell module of the present invention.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. For the sake of clarity, many practical details will be explained in the following description. However, it should be understood that these practical details are not intended to limit the invention. That is, in some embodiments of the invention, these practical details are not necessary. In addition, some of the conventional structures and elements are shown in the drawings in a simplified schematic manner in order to simplify the drawings.

Please refer to Figure 1 and Figure 2 together. 1 is a schematic structural view showing an embodiment of a solar cell 100 according to the present invention; and FIG. 2 is a schematic structural view showing another embodiment of the solar cell 100 according to FIG. 1.

The solar cell 100 basically includes a substrate 110 and a top surface electrode 120 formed on the top surface 111 of the substrate 110. Here, the substrate 110 includes a structure capable of converting light energy into electrical energy. The photoelectric conversion structure is a conventional technique, and is not particularly described in the present invention. All subsequent embodiments are referred to as a substrate. The substrate 110 further includes a bottom surface and a bottom surface electrode formed on the bottom surface. It should be noted that, in the embodiment of the present invention, the top surface 111 of the substrate 110 is a light absorbing surface, so the present invention mainly changes the configuration of the bus bar electrode 121 and the extension electrode 122 of the top surface electrode 120 to increase the light absorption. Therefore, the bottom electrode can be disposed on the bottom surface of the substrate 110 in various forms that can be understood and understood, and is not particularly discussed. In the embodiment of the present invention, the drawing of the bottom and bottom electrodes will be omitted for ease of understanding. The numbering, but does not mean that there is no such surface and bottom electrode, so it is hereby stated.

The top surface electrode 120 is formed on the top surface 111, and has substantially the following functions: Imprinting, Evaporation, Sputtering, Chemical Vapor Deposition (CVD), and Physical Meteorological Deposition ( Physical Vapor Deposition (PVD) and Atomic Layer Deposition (ALD), which are conventional techniques, will not be described again.

The top electrode 120 includes a bus bar electrode 121 and a plurality of extension electrodes 122. The plurality of extension electrodes 122 extend from the bus bar electrode 121 and have a different direction from the bus bar electrode 121. More specifically, as shown in FIG. 1 or FIG. 2, in a preferred embodiment, the bus bar electrodes 121 are vertically arranged on the top surface 111 of the substrate 110, and the plurality of extension electrodes 122 are respectively confluent. The drain electrodes 121 extend horizontally on both sides and are connected to each other. In this arrangement, a better electrical extraction rate can be obtained.

A first area A1 and a second area A2 are defined on the left and right sides of the bus bar electrode 121, respectively. The area of the extension electrode 122 in the first area A1 is smaller than the area of the extension electrode 122 in the second area A2. More specifically, regardless of the number, shape or size of the extension electrodes 122 in the first region A1, the sum of the areas is smaller than the sum of the areas of the extension electrodes 122 in the second region A2. In the embodiment of the present invention, the top surface 111 of the substrate 110 is a light absorbing surface, and the bus bar electrode 121 and the extension electrode 122 are generally opaque materials (for example, metal), so that the incident light L is blocked and the amount of light absorption is reduced. Reduce the photoelectric conversion efficiency. In the present invention, by limiting the area of the extending electrode 122 in the first area A1 and the second area A2 on the left and right sides of the bus bar electrode 121, the light absorption amount of the first area A1 is larger than the light absorption amount of the second area A2. Thereby, the total light absorption amount of the solar cell 100 can be increased, thereby improving the photoelectric conversion efficiency. In a preferred embodiment, from the first figure, there is almost no extension in the first area A1. The configuration of the electrode 122 is extended to obtain as much light absorption as possible. However, since the solar cell 100 absorbs light, the electric energy converted into the electrode still needs to be taken out by the electrode. Therefore, it is necessary to balance the increase in the amount of light absorption and the maintenance of the electric extraction rate, and the amount of light absorption is increased without limitation; The width is less than or equal to 20 mm; and the width of the first area A1 is equal to the width of the second area A2. Thereby, the solar cell 100 of the present invention not only has a high light absorption amount, but still maintains a good electric extraction rate. In FIG. 2, the first area A1 is farther away from the bus bar electrode 121, so that a larger number of extension electrodes 122 are disposed in the first area A1, but the total area of the extension electrodes 122 is still smaller than that in the second area A2. The sum of the areas of the extension electrodes 122. Thereby, the electric take-out rate in FIG. 2 is different from the electric take-out rate in FIG. 1 so as to be applied to different situations.

Please continue to refer to Figures 3 and 4. 3 is a schematic structural view showing an embodiment of a solar cell 200 using a three bus bar electrode 221 in the present invention; and FIG. 4 is a schematic structural view showing another embodiment of the solar cell 200 according to FIG. The solar cell 200 basically includes a substrate 210 and a top surface electrode 220 disposed on the top surface 211 of the substrate 210. The bottom and bottom electrodes of the substrate 210 will not be discussed in detail, and thus are not depicted.

The difference from the first embodiment in FIG. 1 and FIG. 2 is that in the solar cell 200 of FIGS. 3 and 4, the top surface electrode 220 includes the three bus bar electrodes 221 and thus the three bus bar electrodes 221 A plurality of extension electrodes 222 extending from both sides. Each of the extension electrodes 222 has a different direction from each of the corresponding bus bar electrodes 221. Similar to the previous embodiment, in a preferred embodiment, each bus bar electrode 221 is vertically arranged on the top surface 211 of the substrate 210, and each of the extension electrodes 222 is horizontally extended from both sides of each bus bar electrode 221. Out and connected to each other, a better electrical extraction rate can be obtained in this arrangement.

A first area A1 and a second area A2 are defined on the left and right sides of each of the bus bar electrodes 221. For ease of understanding, the arrangement of the first area A1 and the second area A2 is represented by the centrally located bus bar electrode 221. The other two bus bar electrodes 221 can be analogized by analogy, and will not be described again; in the following embodiments, the description is simplified in this way. The area of the extension electrode 222 in the first area A1 is smaller than the area of the extension electrode 222 in the second area A2. More specifically, regardless of the number, shape or size of the extension electrodes 222 in the first region A1, the sum of the areas is smaller than the sum of the areas of the extension electrodes 222 in the second region A2. By limiting the area of the extension electrode 222 in each of the first area A1 and the second area A2 on the left and right sides of each of the bus bar electrodes 221, the amount of light absorbed by the first area A1 is made larger than the amount of light absorbed by the second area A2. The total light absorption of the solar cell 200 can be increased, thereby improving the photoelectric conversion efficiency.

In order to balance the increase of the light absorption amount with the maintenance of the electric extraction rate, the width of the first region A1 is less than or equal to 20 mm; and the width of the first region A1 is equal to the width of the second region A2. Thereby, the solar cell 200 of the present invention not only has a high light absorption amount, but also maintains a good electric extraction rate. In FIG. 4, the first area A1 is farther away from the bus bar electrode 221, so that a larger number of extended electrodes 222 are disposed in the first area A1, but the total area of the extended electrodes 222 is still smaller than that in the second area A2. The sum of the areas of the extension electrodes 222. Thereby, the electric take-out rate in FIG. 4 is different from the electric take-out rate in FIG. 3 so as to be applied to different conditions.

In the third and fourth figures, the solar cell 200 can be considered to be expanded in units of the solar cells 100 of Figs. 1 and 2 . It should be noted that in FIG. 3 and FIG. 4, in addition to expanding the number of bus bar electrodes 221 in the first and second figures to three, it is also possible to expand The exhibition is any even or odd number to cope with different situations. In addition, in addition to the number of the bus bar electrodes 221, there may be different geometric configurations of the number, shape, size, length, or arrangement between the bus bar electrodes 221 and the extension electrodes 222 thereof. In the following, various embodiments of the application will be described with reference to a plurality of embodiments of FIGS. 5A to 9.

FIG. 5A is a schematic structural view showing an embodiment of a solar cell 200 using the three bus bar electrodes 221 in the present invention; and FIG. 5B is a schematic structural view showing another embodiment of the solar cell 200 according to FIG. 5A. In FIGS. 5A and 5B, structures similar to those of FIGS. 3 and 4 will not be described again. In FIGS. 5A and 5B, it can be seen that the extension electrodes 222 extending from both sides of each bus bar electrode 221 are disconnected from each other. Thereby, different electrical extraction rates can be obtained. In a preferred embodiment, the areas of the first area A1 and the second area A2 on both sides of each of the bus bar electrodes 221 in FIGS. 5A and 5B are respectively the same as those described in the foregoing embodiments.

6A is a schematic structural view showing an embodiment of a solar cell 200 using a triple bus electrode 221 in the present invention; and FIG. 6B is a schematic structural view showing another embodiment of the solar cell 200 according to FIG. 6A. In FIGS. 6A and 6B, structures similar to those of FIGS. 5A and 5B will not be described again. In FIGS. 6A and 6B, it can be seen that the extension electrodes 222 extending from both sides of each bus bar electrode 221 are not only disconnected from each other, but are also alternately arranged. Thereby, different electrical extraction rates can be obtained. In a preferred embodiment, the areas of the first area A1 and the second area A2 on both sides of each of the bus bar electrodes 221 in FIGS. 6A and 6B are respectively the same as those described in the foregoing embodiments.

Fig. 7 is a view showing the structure of an embodiment of a solar cell 200 using a three bus bar electrode 221 in the present invention. In Figure 7, a knot similar to Figure 6A and Figure 6B The structure will not be described separately. In FIG. 7, it can be seen that each of the extension electrodes 222 extending from both sides of each of the bus bar electrodes 221 is not only disconnected from each other, but also alternately arranged with each other, and each of the extension electrodes 222 has a different length. For example, in FIG. 7, the extension electrode 222 extending from the two busbar electrodes 221 on the most lateral side has a length longer than the extension electrode 222 extending from the central bus bar electrode 221. Thereby, different electrical extraction rates can be obtained. In a preferred embodiment, the area of the first area A1 and the second area A2 on both sides of each of the bus bar electrodes 221 in FIG. 7 is the same as that described in the foregoing embodiments.

FIG. 8 is a schematic structural view showing an embodiment of a solar cell 200 using a three-bus bar electrode 221 in the present invention; and FIG. 9 is a schematic structural view showing another embodiment of the solar cell 200 according to FIG. In Figures 8 and 9, similar structures will not be described again. In Figs. 8 and 9, it can be seen that the solar cell 200 has six bus bar electrodes 221. Each of the three bus bar electrodes 221 can be regarded as one unit, and the entire top surface electrode 220 is divided into two units U1 and U2. In the eighth and ninth diagrams, the extension electrodes 222 extending from the three busbar electrodes 221 of the respective units U1 and U2 are connected to each other, and in the unit U1, the two busbar electrodes 221 on the side are connected. The extended outermost extension electrode 222 and the unit U2 are connected to each other by the outermost extension electrode 222 extending from the two busbar electrodes 221 on the side. Thereby, the adjustment of the electric extraction rate and the light absorption amount can be achieved to achieve more precise control. In a preferred embodiment, the areas of the first area A1 and the second area A2 on both sides of each of the bus bar electrodes 221 of the respective units U1 and U2 in FIGS. 8 and 9 are respectively the same as those described in the foregoing embodiments. and.

The various configurations of the top electrodes 120 and 220 of the solar cells 100 and 200 of the present invention have been described above in the respective embodiments. Follow-up, will explain how to use the above The solar cells 100 and 200 form various solar cell modules 300. Referring to FIG. 10 to FIG. 16 , the various structures of the solar cell module 300 are drawn.

The solar cell module 300 includes a backplane 310, a solar cell 200, a package material 320, a light transmissive member 330, and a light-enhancing structure 340.

The solar cell 200 is disposed on the backplane 310, and its structure is as shown in the embodiments in FIGS. 5A to 9 and will not be described again.

The encapsulating material 320 is coated with the solar cell 200 and may be made of Ethylene-Vinyl Acetate Copolymer (EVA) or Poly-Vinyl Butyral (PVB).

The light transmissive member 330 is covered on the encapsulating material 320 and may be made of glass or acryl.

The light-expanding structure 340 is formed at a position corresponding to the bus bar electrode 221 of the solar cell 200. In FIG. 10, after the solar cell module 300 absorbs the incident light L, the light-expanding structure 340 can diffuse the incident light L at the position corresponding to the bus bar electrode 221, thereby further increasing the first side of the bus bar electrode 221. The amount of light absorbed by the area A1 (for the structure of the bus bar electrode 221 and the first area A1 of the solar cell 200, see the respective embodiments in the above-mentioned 5A to 9th drawings, which will not be described herein). In FIG. 10, the light-enhancing structure 340 is formed under the package material 320 in a multilayer reflective film. It should be mentioned that the multilayer encapsulation material 320 itself can also be directly used to form a multilayer reflective film without further structure.

The various configuration changes of the light-emitting structure 340 are described below.

In Fig. 11, the light-expanding structure 340 is formed by doping the plurality of particles P in the encapsulating material 320. The position of the light-enhancing structure 340 corresponds to the position of the bus bar electrode 221.

In Fig. 12, the light-expanding structure 340 is formed by doping the plurality of particles P into the light-transmitting member 330. The position of the light-enhancing structure 340 corresponds to the position of the bus bar electrode 221.

In Fig. 13, the light-expanding structure 340 is formed on the surface of the light-transmitting member 330, which can have various changes, and the surface of the light-expanding structure 340 can be regular or irregular. For example, in FIG. 13, the light-expanding structure 340 is formed at a position corresponding to the bus bar electrode 221 with a single concave surface. In Fig. 14, the light-expanding structure 340 is formed on the surface of the light-transmitting member 330 by a plurality of lenses 341 at positions corresponding to the bus bar electrodes 221 . In Fig. 15, the light-expanding structure 340 is formed on the surface of the light-transmitting member 330 by a plurality of corner posts 342 at positions corresponding to the bus bar electrodes 221 . It is to be noted that the plurality of lenses 341 or the plurality of corner posts 342 may be formed on the surface of the encapsulation material 320 corresponding to the position of the bus bar electrode 221 . In addition, the light-enhancing structure 340 may also be formed on the surface of the encapsulating material 320 corresponding to the position of the bus bar electrode 221 or the surface of the light-transmitting member 330 by chemical etching or physical etching. In Fig. 15, a light-enhancing structure 340 arranged in a plurality of corner posts 342 is formed directly on the bus bar electrode 221. The plurality of corner posts 342 may be arranged in a regular or irregular manner, or may vary in size and size.

In FIG. 16, the light-expanding structure 340 may be formed directly on the bus bar electrode 221 in a ribbon shape, for example, it may be formed on the surface of the bus bar electrode 221 by bonding or soldering. Thereby, when the incident light L is incident on different positions on the light-enhancing structure 340, different angular scattering can be formed to form the incident light L into a plurality of scattered light, such as the scattered light L1 and the scattered light L2. When the scattered light L1 or the scattered light L2 is emitted to the surface of the light transmitting member 330 through the encapsulating material 320, the light transmitting member 330 is reflected and increased in the vicinity of the bus bar electrode 221 (such as the first region A1 described above). The amount of light absorbed. The scattering of the incident light L can also be achieved by forming a regular or irregular roughened surface directly on the surface of the bus bar electrode 221.

In summary, the solar cell and the solar cell module disclosed in the present invention can achieve good light absorption and electric extraction rate through various configurations of the bus bar electrode and the extension electrode of the top electrode on the solar cell. Moreover, in combination with the light-expanding structure formed on the inside or on the surface of the packaging material, the light-transmitting member or the bus bar electrode, the amount of light absorption can be further increased, thereby effectively improving the photoelectric conversion efficiency.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

200‧‧‧ solar cells

210‧‧‧Substrate

211‧‧‧ top surface

220‧‧‧ top electrode

221‧‧‧ bus bar electrode

222‧‧‧Extended electrode

A1‧‧‧ first area

A2‧‧‧Second area

Claims (24)

A solar cell comprising: a substrate having a top surface, wherein the substrate is operable to convert light energy into electrical energy; and a top surface electrode formed on the top surface, the top surface electrode including at least one bus bar An electrode and a plurality of extended electrodes extending from the bus bar electrode, wherein the bus bar electrode and the extension electrodes have different directions, and a first region is defined on the left and right sides of the bus bar electrode and the first region The area is adjacent to the second area of the same side, and each of the first areas is adjacent to the bus bar electrode, wherein the extension electrode areas in each of the first areas are smaller than the extension electrodes in each of the second areas The area, and the width of each of the first regions is equal to the width of each of the second regions. The solar cell of claim 1, further comprising: a bottom electrode formed on a bottom surface of the solar cell. The solar cell of claim 1, wherein the width of the first region is less than or equal to 20 mm. The solar cell of claim 1, wherein the top surface is a light absorbing surface, and the light absorption amount of the first region is greater than the light absorption amount of the second region. The solar cell of claim 1, wherein the top surface electrode comprises three bus bar electrodes, and each of the bus bar electrodes extends a plurality of extension electrodes, each of which Each of the first region and each of the second regions is defined on both sides of the bus bar electrode, wherein the extension electrode areas in each of the first regions are smaller than the extension electrode regions in each of the second regions. The solar cell of claim 5, wherein each of the first regions has a width of 20 mm or less. The solar cell of claim 5, wherein the width of each of the first regions is equal to the width of each of the second regions. The solar cell of claim 5, wherein the extension electrodes extending from each of the bus bar electrodes are connected or disconnected in parallel with each other. The solar cell of claim 5, wherein the extension electrodes extending from each of the bus bar electrodes are staggered with each other. A solar cell module comprising: a backing plate; a solar cell disposed on the backing plate, the solar cell comprising: a substrate having a top surface, wherein the substrate is operable to convert light energy into electrical energy; a top surface electrode is formed on the top surface, the top surface electrode includes at least one bus bar electrode and a plurality of extension electrodes extending from the bus bar electrode, wherein the bus bar electrode and the plurality of electrodes The extension electrodes have different directions, and define a first region adjacent to the left and right sides of the bus bar electrode and a second region adjacent to the first region and located on the same side, and each of the first regions is adjacent to the first region a bus bar electrode, wherein the extension electrode areas in each of the first regions are smaller than the extension electrode areas in each of the second regions, and the width of each of the first regions is equal to the width of each of the second regions; The material covers the solar cell; and a light-transmitting member covers the packaging material; wherein a light-expanding structure is formed at a position corresponding to the bus bar electrode, and the light-absorbing structure is configured to make the light-absorbing amount of each of the first regions larger than each The amount of light absorbed by the second region. The solar cell module of claim 10, wherein the light-expanding structure is formed by doping a plurality of particles in the encapsulating material or the light transmissive member, and the position of the light-expanding structure corresponds to a bus bar electrode position. The solar cell module according to claim 10, wherein the light-expanding structure is directly formed on the bus bar electrode in a strip shape, and the surface of the light-expanding structure is regular or irregular. The solar cell module of claim 12, wherein the light-expanding structure is formed on the surface of the bus bar electrode by bonding or soldering. The solar cell module of claim 10, wherein the light-expanding structure is formed on the surface of the light-transmissive member or the surface of the encapsulating material, and the surface of the light-expanding structure is regular or irregular. The solar cell module according to claim 10, wherein the light-expanding structure is formed by arranging a plurality of lenses or a plurality of corner posts. The solar cell module of claim 10, wherein the light-expanding structure forms a roughened surface on the surface of the encapsulating material, the surface of the transmissive member or the surface of the bus bar electrode. The solar cell module of claim 10, wherein the light transmissive member is a light transmissive glass or acrylic. The solar cell module according to claim 10, wherein the encapsulating material is Ethylene-Vinyl Acetate Copolymer (EVA) or Poly-Vinyl Butyral (PVB). ). The solar cell module of claim 10, wherein the top surface electrode comprises three bus bar electrodes, and each of the bus bar electrodes extends a plurality of extension electrodes, and each of the bus bar electrodes defines each of the first electrodes a region and each of the second regions, wherein the extension electrode areas in each of the first regions are smaller than the extension electrode regions in each of the second regions. The solar cell module according to claim 19, wherein each of the first regions has a width of 20 mm or less. The solar cell module of claim 19, wherein a width of each of the first regions is equal to a width of each of the second regions. The solar cell module of claim 19, wherein the extension electrodes extending from each of the bus bar electrodes are connected or disconnected in parallel with each other. The solar cell module of claim 19, wherein the extension electrodes extending from the bus bar electrodes are staggered with each other. The solar cell module of claim 10, comprising a plurality of the solar cells arranged in an array on the backplane.