TW201438256A - Solar cell, method of manufacturing the same and module comprising the same - Google Patents

Abstract

A solar cell, a method of manufacturing the same and a module comprising the same are provided. The solar cell comprises a substrate and at least a first electrode unit having a plurality of first electrode members. Each of the first electrode members has a first bus bar portion, a second bus bar portion, a first side portion, and a second side portion. The first side portion has a first collecting segment extending from the first bus bar portion along a second direction. The second side portion has a second collecting segment extending from the first bus bar portion along the second direction. The width of the first bus bar portion is larger than that of the first collecting segment. The width of the second bus bar portion is larger than that of the second collecting segment. The structural design of the solar cell can reduce the consumption of a conductive paste and the manufacturing costs and maintain the production yield and the reliability of the solar cell.

Description

Solar cell, manufacturing method thereof and module thereof

The invention relates to a battery, a manufacturing method thereof and a module thereof, in particular to a solar battery, a manufacturing method thereof and a module thereof.

Referring to FIGS. 1 and 2, a general solar cell generally includes a substrate 91, an emitter layer 92 located at a front surface 99 of the substrate 91, an anti-reflection layer 93 on the emitter layer 92, and a configuration. A positive electrode unit 94 that contacts the anti-reflective layer 93 and contacts the emitter layer 92, and a back electrode unit 95 disposed on a back surface 98 of the substrate 91.

The front surface 99 of the substrate 91 is a light-receiving surface, and the substrate 91 and the emitter layer 92 form a p-n junction through a semiconductor process technology, which is a source of photovoltaic effects. The anti-reflection layer 93 is used to reduce the loss of incident light to increase the current. The positive electrode unit 94 includes a plurality of bus bar electrodes 941 disposed on the front surface 99 and contacting the emitter layer 92, and a plurality of finger bar electrodes 942 connecting the plurality of bus electrodes 941. .

In manufacturing, the plurality of bus electrodes 941 and the plurality of finger electrodes 942 can be formed by screen printing metal paste, due to the conductive paste The material is mainly silver (Ag), which is expensive, and the general bus electrode 941 is printed as a whole continuous linear body, so the amount of the metal paste is large and the manufacturing cost is increased. Therefore, if the area of the plurality of bus electrodes 941 disposed on the front surface 99 can be reduced to reduce the consumption of the conductive paste, the manufacturing cost can be reduced.

On the other hand, after the solar cell is manufactured, several solar cells and other components are usually packaged into a solar cell module. Wherein, the plurality of solar cells must be soldered to the plurality of bus electrodes 941 by a plurality of ribbons to electrically connect the adjacent solar cells.

Although it is an important subject to improve the structure of the plurality of bus electrodes 941 to save costs, it is also necessary to consider the welding bonding force between the plurality of bus electrodes 941 and the solder ribbon. If the area of the plurality of bus electrodes 941 is reduced only blindly, the problem of the solder ribbon falling off easily occurs when the module is packaged, thereby reducing the manufacturing yield and the reliability of use.

Accordingly, it is an object of the present invention to provide a solar cell which can save conductive paste to reduce manufacturing cost and has good manufacturing yield and reliability.

Thus, the solar cell of the present invention comprises: a substrate, and at least one first electrode unit.

The substrate includes a light receiving surface. The first electrode unit includes a plurality of first electrode groups arranged on the light receiving surface at intervals in a first direction, each of the first electrode groups having only a first confluence portion and a first direction a second confluence portion, a first side portion, and a second side portion disposed at intervals from the first confluence portion, each of the first side portions having a first portion of the first confluence portion along a vertical direction a first collecting portion extending in two directions, each second side portion having a second collecting portion extending in the second direction from the second collecting portion opposite to the first collecting portion, arranged along the first direction The width of each of the first confluences is greater than the width of each of the first collection portions, and the width of each of the second confluences arranged along the first direction is greater than the width of each of the second collection portions.

Another object of the present invention is to provide a solar cell module comprising: a first plate and a second plate spaced apart, and a plurality of arrays as described above and arrayed on the first plate and the first a solar cell between the two plates, a plurality of soldering strips respectively disposed on the corresponding solar cells extending along the first direction, and a layer between the first plate and the second plate and coated thereon a plurality of solar cells surrounding the package, and each of the solder ribbons is connected to and covers the plurality of first busses and the plurality of second busbars of the corresponding solar cells.

Still another object of the present invention is to provide a method for producing a solar cell according to the present invention, which comprises: (A) applying a first slurry to the light-receiving surface of the substrate by screen printing, and drying the first a slurry; (B) after coating a second slurry on the light receiving surface by screen printing, drying the second slurry; and (C) sintering the first slurry and the second slurry, The first slurry is formed into the plurality of first confluence portions and the plurality of second confluence portions, and the second slurry is formed into the plurality of first collection portions and the plurality of second collection portions.

The utility model has the advantages that the plurality of first busbars and the plurality of second busbars are spaced apart from each other on the substrate, and the plurality of solder ribbons are still saved while saving the conductive paste to reduce the manufacturing cost. The combination of the plurality of first confluence portions and the plurality of second confluence portions can maintain good bonding and welding stability, so that the present invention can maintain the manufacturing yield and the reliability of use in subsequent welding operations.

11‧‧‧ first plate

12‧‧‧Second plate

13‧‧‧Solar battery

14‧‧‧ soldering tape

15‧‧‧Package

2‧‧‧Substrate

21‧‧‧Stained surface

22‧‧‧ Back

3‧‧‧First electrode unit

30‧‧‧First electrode group

31‧‧‧ First Confluence Department

32‧‧‧Second Confluence Department

33‧‧‧First Collection Department

331‧‧‧First collection section

332‧‧‧First expansion section

34‧‧‧Second Collection Department

341‧‧‧Second collection section

342‧‧‧Second expansion section

35‧‧‧First Auxiliary Department

351‧‧‧First extension

352‧‧‧First connection segment

36‧‧‧Second Auxiliary Department

361‧‧‧Second extension

362‧‧‧Second connection

37‧‧‧First side

38‧‧‧ second side

4‧‧‧Second electrode unit

40‧‧‧Second electrode group

41‧‧‧ Third Confluence Department

42‧‧‧ Fourth Confluence Department

43‧‧‧ Third Collection Department

44‧‧‧ Fourth Collection Department

47‧‧‧ Third side

48‧‧‧ fourth side

5‧‧‧ third electrode unit

50‧‧‧ third electrode group

51‧‧‧ Fifth Confluence Department

52‧‧‧ Sixth Confluence Department

53‧‧‧The Fifth Collection Department

57‧‧‧ Fifth side

71‧‧‧First slurry

72‧‧‧Second slurry

81‧‧‧First direction

82‧‧‧second direction

L1~L9‧‧‧Width

D1~D2‧‧‧Deep

T1~T2‧‧‧ thickness

Other features and effects of the present invention will be apparent from the following description of the drawings. FIG. 1 is a front view of a general solar cell; FIG. 2 is a cross-sectional view taken along line AA of FIG. FIG. 3 is a partial cross-sectional view showing a first preferred embodiment of the solar cell module of the present invention; FIG. 4 is a top plan view showing the solar cell of the first preferred embodiment separately; FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 6 is a schematic cross-sectional view showing the structure of the solar cell before and after sintering in the first embodiment of the manufacturing method; FIG. 7 is a schematic flow chart of a preferred embodiment of the method for manufacturing a solar cell; 6 is a schematic view showing the structure of the solar cell before and after sintering in the second embodiment of the manufacturing method; FIG. 8 is a plan view showing a second preferred embodiment of the solar cell module of the present invention. a solar cell; FIG. 9 is a top view showing one of the solar cell modules of the present invention separately A solar cell of a third preferred embodiment; FIG. 10 is a plan view showing a solar cell of a fourth preferred embodiment of the solar cell module of the present invention; FIG. 11 is a top view showing the fourth preferred embodiment. The plurality of solder ribbons of the embodiment may cover a plurality of first confluence portions and a plurality of second confluence portions of the solar cell; FIG. 12 is a top view showing a fifth comparison of the solar cell module of the present invention. a solar cell of a preferred embodiment; FIG. 13 is a plan view showing a solar cell of a sixth preferred embodiment of the solar cell module of the present invention; FIG. 14 is a top view showing the solar cell module of the present invention separately A solar cell according to a seventh preferred embodiment; and FIG. 15 is a plan view showing a solar cell of an eighth preferred embodiment of the solar cell module of the present invention.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

Referring to FIGS. 3 and 4, a first preferred embodiment of the solar cell module of the present invention comprises: a first plate 11 and a second plate 12 spaced apart from each other, and a plurality of arrays arranged on the first plate 11 and the array a solar cell 13 between the second sheets 12, a plurality of solder strips 14 respectively disposed on the corresponding solar cells 13 along a first direction 81, and a first sheet 11 and the second sheet A package 15 between 12 and surrounding the plurality of solar cells 13. Of course, in implementation, the sun The energy battery module may include only one solar battery 13.

In this embodiment, the second plate 12 is also referred to as a back sheet. The first plate 11 is located on the side where the light is incident. The second plate 12 may be made of a light-transmitting material, such as a glass or plastic material. Special restrictions are required. The material of the package material 15 is ethylene-vinyl acetate copolymer (EVA) or other related materials that can be used for solar cell module packaging, and is not limited to the examples of the embodiment. Since the structure of the solar cell module is not an improvement of the present invention, it will not be described again, and is also simply illustrated in FIG. The structures of the plurality of solar cells 13 are the same, and only one of them will be described below as an example.

The solar cell 13 includes a substrate 2 for converting light energy into electrical energy, and two first electrode units 3 respectively disposed on the substrate 2 at intervals along a second direction 82 perpendicular to the first direction 81. . In practice, the solar cell 13 can of course also comprise only a first electrode unit 3 .

The substrate 2 of the present embodiment includes a light receiving surface 21 and a back surface 22 opposite to the light receiving surface 21. In fact, the substrate 2 includes a substrate body, an emitter layer formed on a surface of the substrate body and forming a pn junction with the substrate body, and a film layer such as an anti-reflection layer (for example, SiN _x ). However, since the specific structure of the substrate 2 and how the substrate 2 converts light energy into electrical energy are not the improvement points of the present invention, they will not be described again, and only a single layer is simply illustrated in FIG.

Each of the first electrode units 3 of the embodiment includes a plurality of first electrode groups arranged on the light receiving surface 21 at intervals in the first direction 81. 30. Each of the first electrode groups 30 has only a first confluence portion 31, a second confluence portion 32 spaced apart from the first confluence portion 31 in the first direction 81, a first side portion 37, and a second portion. Side 38. Each of the first side portions 37 has a first collecting portion 33 extending outward from the first confluence portion 31 in the second direction 82, and each of the second side portions 38 has a reverse direction from the first collecting portion 33. The second collecting portion 34 extends outward from the second confluence portion 32 in the second direction 82.

The first collecting portion 33 and the second collecting portion 34 of each of the first electrode groups 30 are respectively located on different straight lines extending parallel to the second direction 82, that is, the plurality of first collecting portions 33 and the number The second collecting portions 34 are sequentially staggered along the first direction 81, respectively.

The plurality of first confluences 31 and the plurality of second confluences 32 are all rectangular, and the width L1 of each of the first confluences 31 arranged along the first direction 81 is greater than the width of each of the first collections 33 L2. The width L3 of each of the second confluences 32 arranged along the first direction 81 is greater than the width L4 of each of the second collection portions 34. Further, the width L1 and the width L3 of the present embodiment may be the same or different, and the width L2 and the width L4 may be the same or different.

Of course, the solar cell 13 further includes a back electrode unit (not shown) disposed on the back surface 22 of the substrate 2, and the solder ribbon 14 of the present embodiment is used to electrically connect the adjacent two solar cells 13 respectively. Each of the solder ribbons 14 is connected to the first confluence portion 31 and the second confluence portion 32 of one of the first electrode units 3 of one of the solar cells 13, and the solder ribbon 14 is also connected to another solar cell 13 adjacent thereto. Back electrode at back 22 Thus, the plurality of solar cells 13 are electrically connected.

Referring to Figures 4 and 5, a preferred embodiment of the method of fabricating a solar cell of the present invention comprises the following steps:

Step (A): After applying a first slurry 71 to the light-receiving surface 21 of the substrate 2 by screen printing, the first slurry 71 is baked. The first slurry 71 is, for example, a silver paste.

Step (B): After applying a second slurry 72 on the light receiving surface 21 by screen printing, the second slurry 72 is baked. The second slurry 72 is, for example, a silver paste.

Step (C): sintering the first slurry 71 and the second slurry 72, so that the first slurry 71 forms the plurality of first confluence portions 31 and the plurality of second confluence portions 32, and The second slurry 72 is formed into a first collecting portion 33 of the plurality of first side portions 37 and a second collecting portion 34 of the plurality of second side portions 38.

It should be noted that the order of step (A) and step (B) can be reversed. In addition, the area of the plurality of first confluence portions 31 and the plurality of second confluence portions 32 disposed on the light receiving surface 21 is larger than the area of the plurality of first collection portions 33 and the plurality of second collection portions 34, That is, the amount of the first slurry 71 is greater than that of the second slurry 72. Therefore, silver paste having a relatively cheap price can be selected as the first slurry 71 in practice, thereby further saving cost, and specifically, the following two Different implementations.

Referring to FIGS. 5 and 6, in the first embodiment of the manufacturing method, the first slurry 71 and the second slurry 72 have the same solid content of silver, but due to the erosive ability of the first slurry 71. a higher proportion of material composition, The etching force of the first slurry 71 during the sintering operation is strong.

When the first slurry 71 and the second slurry 72 are applied to the light-receiving surface 21 via the steps (A) and (B), both have the same thickness. After the sintering operation of the step (C), the first slurry 71 has a strong erosive force, and the plurality of first confluent portions 31 and the plurality of second confluence portions 32 formed are eaten downward toward the substrate 2. The depth D1 of the wear is deeper, and the second slurry 72 has a weaker erosive force, and the first collecting portion 33 of the plurality of first side portions 37 and the second portion of the plurality of second side portions 38 are formed. The depth D2 at which the collecting portion 34 is worn down toward the substrate 2 is shallow.

Referring to FIGS. 5 and 7, in the second embodiment of the manufacturing method, the solid content of silver in the first slurry 71 and the second slurry 72 is different, wherein the solid content of silver in the first slurry 71 is Lower and cheaper.

When the first slurry 71 and the second slurry 72 are applied to the light-receiving surface 21 via the steps (A) and (B), both have the same thickness. After the sintering operation of the step (C), the first slurry 71 has a thin solid content of silver, and the plurality of first confluent portions 31 and the thickness T1 of the plurality of second confluence portions 32 are thin. . The second slurry 72 has a high solid content of silver, and the first collecting portion 33 of the plurality of first side portions 37 and the thickness T2 of the second collecting portion 34 of the plurality of second side portions 38 are formed. Thicker.

Referring to FIGS. 4 and 5, it can be seen from the above description that the first busbar portion 31 and the plurality of second portions are compared with the method in which the bus electrode of a general solar cell is printed as a whole continuous linear body. The structural design of the confluence portion 32 is spaced apart, and the plurality of solder ribbons are saved while saving the conductive paste. The plurality of first confluence portions 31 and the plurality of second confluence portions 32 can maintain good bonding and soldering stability. Therefore, the plurality of solder ribbons 14 are not easily peeled off when the module is packaged.

In addition, the plurality of first confluence portions 31 and the plurality of second confluence portions 32 respectively have the design of the plurality of first collection portions 33 and the plurality of second collection portions 34 on one side thereof, and the slurry can be saved. The first collecting portion 33 of the plurality of first side portions 37 and the second collecting portion 34 of the plurality of second side portions 38 are reversely arranged to have a better current collecting effect. It has been confirmed by experiments by the inventors that the present embodiment can maintain the manufacturing yield and the reliability of use in the subsequent welding operation, and can reduce the consumption of the conductive paste by 30% in comparison with the general practice, so that the manufacturing cost can be reduced.

In addition to the foregoing method of improving the structure of the improved electrode in a cost-saving manner, in the embodiment, the first slurry 71 which is less expensive may be used to manufacture the plurality of first confluence portions 31 which are used in a larger amount. With the plurality of second busbars 32, the manufacturing cost can be further reduced.

Referring to FIG. 8, a second preferred embodiment of the solar cell module of the present invention is substantially the same as the first preferred embodiment, and the difference between the two is that the first collecting portion 33 of each of the first side portions 37 has a first collecting section 331 extending along the second direction 82, and a first expanding section 332 connected between the first collecting section 331 and the first converging portion 31, wherein each first expanding section 332 is The width of the first direction 81 is gradually increased by one end connecting the first collecting section 331 toward one end of the first converging portion 31.

The second collecting portion 34 of each of the second side portions 38 has a second collecting portion 341 extending in the second direction 82, and a second connecting portion between the second collecting portion 341 and the second collecting portion 32. The second expansion section 342 has a width in the first direction 81 of each of the second expansion sections 342 gradually increasing from one end connected to the second collection section 341 toward one end of the second confluence portion 32.

The first collecting portion 33 of the plurality of first side portions 37 and the second collecting portion 34 of the plurality of second side portions 38 are for collecting currents transmitted from the substrate 2, and respectively transmitting currents to the numbers The first bus bar portion 31 and the plurality of second bus bar portions 32 finally pass the current through the plurality of solder ribbons 14 outward.

For each of the first electrode groups 30, the current applied to the first collecting portion 33 closer to the first collecting portion 31 is larger, so the influence of the line impedance of the first collecting portion 33 is also affected. The structure of the first expansion portion 332 is gradually increased in the direction of the first confluence portion 31 by the width of the first expansion portion 332, and the first collection portion 33 is increased in the first direction 81. The upper cross-sectional area, in turn, reduces the resistance to reduce current consumption, thereby improving current collection efficiency.

The second expansion section 342 of the second collection portion 34 of each of the first electrode groups 30 can achieve the same effect and will not be described in detail. In addition, each of the first confluence portions 31 and each of the second confluence portions 32 are trapezoidal and have a gradually wide structural design, which can also improve current collection efficiency. In addition, since the manufacturing method of the present embodiment is the same as the first preferred embodiment, it will not be described.

Referring to FIG. 9, a third preferred embodiment of the solar cell module of the present invention is substantially the same as the second preferred embodiment. The difference between the two is that the solder ribbon 14 of the embodiment is in the second direction 82. The width L5 is larger than the width of the solder ribbon of the second preferred embodiment, and can simultaneously cover the plurality of first confluence portions 31, the plurality of second confluence portions 32, the plurality of first expansion segments 332, and the same After the solar cells 13 of the present embodiment are connected to the plurality of solder ribbons 14, the solar cells 13 of the present embodiment will be identical to the conventional conventional solar cells.

Through the foregoing design, the area in which the plurality of first electrode units 3 are soldered to the plurality of solder ribbons 14 can be increased, so that the embodiment has superior soldering stability and further improves the manufacturing of the solar cell module. Yield and reliability of use.

Of course, in practice, the plurality of solder ribbons 14 may cover only a portion of the plurality of first expanded segments 332 and the plurality of second expanded segments 342. Therefore, the size of the plurality of solder ribbons 14 and the extent to which the plurality of first expanded segments 332 and the plurality of second expanded segments 342 are covered by the plurality of solder ribbons 14 can be adjusted according to requirements, and are not implemented in the present embodiment. The examples disclosed in the examples are limited.

Referring to FIG. 10, a fourth preferred embodiment of the solar cell module of the present invention is substantially the same as the first preferred embodiment, and the difference between the two is that, for each of the first electrode groups 30, each of the first The first collecting portion 31 and the second collecting portion 32 of the first electrode portion 30 are triangular, and the first collecting portion 33 of the first side portion 37 and the second collecting portion 34 of the second side portion 38 are respectively connected to the first portion a confluence portion 31 and an apex of the second confluence portion 32, and the first collection portion 33 and the second collection portion 34 are located along the parallel The second direction 82 is on a straight line.

In the implementation, the first collecting portion 33 and the second collecting portion 34 of each of the first electrode groups 30 may be respectively connected to the sides of the first collecting portion 31 and the second collecting portion 32, and is not limited to the implementation. The example disclosed in the example. In addition, although each of the solder ribbons 14 of the present embodiment completely covers the first confluence portion 31 and the second confluence portion 32 of each of the first electrode units 3, in practice, each of the solder ribbons 14 may also be as shown in FIG. Only the partial portions of the first confluence portion 31 and the second confluence portion 32 of each of the first electrode units 3 are shown.

Referring to FIG. 12, a fifth preferred embodiment of the solar cell module of the present invention is substantially the same as the first preferred embodiment. The difference between the two is that the solar cell 13 includes a substrate 2 and The second direction 82 is arranged on a first electrode unit 3 and a second electrode unit 4 disposed on the light receiving surface 21 of the substrate 2 .

The second electrode unit 4 includes a plurality of second electrode groups 40 arranged at intervals in the first direction 81, and the plurality of second electrode groups 40 and the plurality of first electrode groups 30 of the first electrode unit 3, respectively. Corresponding. Each of the second electrode groups 40 has only a third confluence portion 41 disposed at a distance from the first confluence portion 31 along the second direction 82, and is spaced apart from and connected to the third confluence portion 41 along the first direction 81. The fourth collecting portion 42 of the second collecting portion 34, a third side portion 47, and a fourth side portion 48. Each of the third side portions 47 has a third collecting portion 43 extending in the second direction 82 between the first confluence portion 31 and the third converging portion 41, and each of the fourth side portions 48 has a The fourth confluence portion 42 is opposite to the third collection portion 43 A fourth collection portion 44 extending along the second direction 82.

The width L6 of each of the third confluences 41 arranged along the first direction 81 is greater than the width L7 of each of the third collection portions 43. The width L8 of each of the fourth confluences 42 arranged along the first direction 81 is greater than the width L9 of each of the fourth collection portions 44. Wherein, the width L6 and the width L8 may be the same or different, and the width L7 and the width L9 may be the same or different.

The light receiving surface 21 of the solar cell 13 is provided with two soldering strips 14 , one of which is connected to and covers the first confluent portion 31 and the second confluent portion 32 of the first electrode unit 3 , and The other of the two solder ribbons 14 is connected to and covers the third confluence portion 41 and the fourth confluence portion 42 of the second electrode unit 4.

The screen printing pastes of the plurality of third bussing portions 41 and the plurality of fourth bussing portions 42 may be the same as the plurality of first bussing portions 31 and the plurality of second confluent portions 32, and the plurality of The screen printing paste of the three collecting portions 43 and the plurality of fourth collecting portions 44 may be the same as the plurality of first collecting portions 33 and the plurality of second collecting portions 34, and the manufacturing method is the same as the above, and will not be described in detail. .

Referring to FIG. 13, a sixth preferred embodiment of the solar cell module of the present invention is substantially the same as the fourth preferred embodiment. The difference between the two is that the solar cell 13 includes a substrate 2 and The second direction 82 is arranged on a first electrode unit 3 and a third electrode unit 5 disposed on the light receiving surface 21 of the substrate 2 .

The third electrode unit 5 includes a plurality of third electrode groups 50 arranged at intervals in the first direction 81, and the plurality of third electrode groups 50 and the plurality of first electrode groups 30 of the first electrode unit 3 respectively Corresponding. Every The third electrode group 50 has only a fifth confluence portion 51 connected to the second collection portion 34, a sixth confluence portion 52 spaced apart from the fifth confluence portion 51 in the first direction 81, and a fifth side. Part 57. Each of the fifth side portions 57 has a fifth collecting portion 53 extending from the sixth confluent portion 52 in the second direction 82. The fifth collecting portion 53 and the second collecting portion 34 are located along the second parallel portion. A straight line of direction 82.

The light receiving surface 21 of the solar cell 13 is provided with two soldering strips 14 , one of which is connected to and covers the first confluent portion 31 and the second confluent portion 32 of the first electrode unit 3 , and The other of the two solder ribbons 14 is connected to and covers the fifth confluence portion 51 and the sixth confluence portion 52 of the third electrode unit 5.

In addition, the screen printing pastes of the plurality of fifth busbars 51 and the plurality of sixth busbars 52 may be the same as the plurality of first bussing sections 31 and the plurality of second bustling sections 32, and the plurality of The fifth collecting portion 53 of the five side portions 57 may be the same as the plurality of first collecting portions 33 and the plurality of second collecting portions 34, and the manufacturing method is the same as the above, and will not be described in detail.

Referring to FIG. 14, a seventh preferred embodiment of the solar cell module of the present invention is substantially the same as the first preferred embodiment, and the difference between the two is: the first of each of the first electrode groups 30 of the present embodiment. The first portion 37 of each of the first electrode groups 30 further has a first auxiliary portion 35 connected to the first collecting portion 33, and each of the first electrode groups 30. The second side portion 38 also has a second auxiliary portion 36 that connects the second collecting portion 34.

Each of the first auxiliary portions 35 has a second direction 82 along the second direction An extended first extending section 351 and a first connecting section 352 extending along the first direction 81 and connecting the first extending section 351 and the first collecting portion 33. Each of the second auxiliary portions 36 has a second extending portion 361 extending along the second direction 82, and a second portion extending along the first direction 81 and connecting the second extending portion 361 and the second collecting portion 34. Two connection segments 362. Therefore, by adding the plurality of first auxiliary portions 35 and the plurality of second auxiliary portions 36 to assist in collecting current, the present embodiment has a more excellent current collecting effect.

Referring to FIG. 15, an eighth preferred embodiment of the solar cell module of the present invention is substantially the same as the seventh preferred embodiment. The difference between the two is that the two first electrode units 3 of the solar cell 13 are mutually Connected.

Specifically, the second collecting portion 34 of one of the first electrode units 3 is respectively connected to the first collecting portion 33 of the other first electrode unit 3, and the second of the second auxiliary portion 36 of one of the first electrode units 3 The extensions 361 are respectively connected to the first extensions 351 of the first auxiliary portions 35 of the other first electrode unit 3.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

13‧‧‧Solar battery

14‧‧‧ soldering tape

2‧‧‧Substrate

21‧‧‧Stained surface

3‧‧‧First electrode unit

30‧‧‧First electrode group

31‧‧‧ First Confluence Department

32‧‧‧Second Confluence Department

33‧‧‧First Collection Department

34‧‧‧Second Collection Department

37‧‧‧First side

38‧‧‧ second side

81‧‧‧First direction

82‧‧‧second direction

L1~L4‧‧‧Width

Claims (12)

A solar cell comprising: a substrate comprising a light receiving surface; and at least one first electrode unit comprising a plurality of first electrode groups arranged on the light receiving surface at intervals in a first direction, each of the first electrode groups Having only a first confluence portion, a second confluence portion disposed at a distance from the first confluence portion along the first direction, a first side portion, and a second side portion, each of the first side portions having a The first collecting portion extends along a first collecting portion extending in a second direction perpendicular to the first direction, and each of the second side portions has a second confluence portion along the second opposite to the first collecting portion a second collecting portion extending in a direction, a width of each of the first confluent portions arranged in the first direction is greater than a width of each of the first collecting portions, and a width of each of the second confluent portions arranged in the first direction is greater than each The width of a second collection portion. The solar cell of claim 1, wherein the first collecting portion and the second collecting portion of each of the first electrode groups are located on different straight lines extending in parallel with the second direction. The solar cell of claim 1, wherein the first collecting portion and the second collecting portion of each of the first electrode groups are located on a line extending in parallel with the second direction. The solar cell of claim 1, wherein each of the first collecting portions has a first collecting section extending in the second direction, and one is connected between the first collecting section and the first collecting section. a first expansion section, each of the first expansion sections is connected by a width in the first direction One end of the first collecting section is gradually increased toward one end of the first collecting portion, and each of the second collecting portions has a second collecting section extending in the second direction, and one is connected to the second collecting section a second expansion section between the second manifolds, wherein the width of each of the second expansion sections in the first direction is gradually increased by connecting one end of the second collection section toward one end of the second junction. The solar cell of claim 1, wherein the plurality of first confluences are triangular or rectangular. The solar cell of claim 1, wherein the first side portion of each of the first electrode groups further has a first auxiliary portion connected to the first collecting portion, and the second side portion of each of the first electrode groups further There is a second auxiliary portion connected to the second collecting portion. The solar cell of claim 6, wherein each of the first auxiliary portions has a first extending portion extending in the second direction, and a first connection connecting the first extending portion and the first collecting portion a segment, wherein each of the second auxiliary portions has a second extending portion extending in the second direction, and a second connecting portion connecting the second extending portion and the second collecting portion. The solar cell according to any one of claims 1 to 7, comprising two first electrode units arranged at intervals along the second direction. The solar cell according to any one of claims 1 to 7, further comprising a second electrode unit disposed on the light receiving surface, the second electrode unit comprising a plurality of second spaced apart along the first direction An electrode group, each of the second electrode groups having only one along the second direction and the first confluence a third confluence portion disposed at a portion interval, a fourth confluence portion, a third side portion, and a fourth side portion, which are disposed at intervals in the first direction and connected to the third confluence portion, and each of the fourth side portion a third side portion has a third collecting portion extending in the second direction and extending between the first confluent portion and the third confluent portion, each fourth side portion having a third opposite to the third collecting portion a fourth collecting portion extending in the second direction from the fourth confluence portion, a width of each of the third confluence portions arranged in the first direction being greater than a width of each of the third collecting portions, along the first direction The width of each of the fourth confluences is greater than the width of each of the fourth collections. The solar cell according to any one of claims 1 to 7, further comprising a third electrode unit disposed on the light receiving surface, the third electrode unit comprising a plurality of third cells arranged at intervals along the first direction The electrode group, each of the third electrode groups has only a fifth bus portion connected to the second collecting portion, a sixth bus portion disposed at a distance from the fifth bus portion in the first direction, and a fifth side portion Each fifth side portion has a fifth collecting portion extending in the second direction by the sixth bus bar. A solar cell module comprising: a first plate and a second plate spaced apart; and a plurality of solar cells according to claim 1 arranged in an array between the first plate and the second plate; The soldering strips are respectively disposed on the corresponding solar cells extending along the first direction, and each of the soldering strips is connected and covers the plurality of first confluent portions of the solar cells corresponding thereto and the plurality of second sinks And a packaging material between the first plate and the second plate and surrounding the plurality of solar cells. A method for manufacturing a solar cell according to claim 1, comprising: (A) applying a first slurry to the light-receiving surface of the substrate by screen printing, and drying the first slurry; (B) After coating a second slurry on the light receiving surface by screen printing, drying the second slurry; and (C) sintering the first slurry and the second slurry to make the first slurry The plurality of first confluences and the plurality of second confluences are formed, and the second slurry forms the plurality of first collection portions and the plurality of second collection portions.