KR20190041268A - Solar cell and solar cell panel including the same - Google Patents

Abstract

According to an embodiment of the present invention, a solar cell panel comprises: a plurality of solar cells including first and second solar cells; and a connection member connecting the first solar cell and the second solar cell between overlapping parts of the first and second solar cells. Each of the solar cells includes: a semiconductor substrate having a long axis and a short axis crossing each other; a conductive region formed on the semiconductor substrate; and an electrode electrically connected to the conductive region. The electrode includes: a plurality of finger lines extending in a first direction parallel to the long axis and parallel to each other; and a plurality of bus bars extending in a second direction parallel to the short axis to be connected to the finger lines, and spaced apart from each other in the first direction. The overlapping parts and the connection member extend in the first direction at one side of the second direction.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a solar cell,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell and a solar cell panel including the same. More particularly, the present invention relates to a solar cell improved in structure and a solar cell panel including the same.

With the recent depletion of existing energy sources such as oil and coal, interest in alternative energy to replace them is increasing. Among them, solar cells are attracting attention as a next-generation battery that converts solar energy into electric energy. In solar cells, various layers and electrodes can be fabricated by design. Since such a solar cell must be exposed to an external environment for a long time, it is manufactured in the form of a solar cell panel by a packaging process for protecting the solar cell.

The manufacturing efficiency, output, and productivity of the solar cell or the solar cell panel can be changed according to the design of the various layers and electrodes of the solar cell, the connection structure thereof, and the like. Accordingly, it is required to manufacture and connect solar cells with a structure that can improve efficiency, output, and productivity of solar cells and solar panels.

The present invention provides a solar cell capable of improving efficiency and productivity.

The present invention also provides a solar cell panel capable of improving output and productivity.

A solar cell panel according to an embodiment of the present invention includes: a plurality of solar cells including first and second solar cells; And a connecting member connecting the first solar cell and the second solar cell between the overlapped portions of the first and second solar cells. Wherein each of the plurality of solar cells comprises: a semiconductor substrate having a major axis and a minor axis intersecting with each other; A conductive type region formed on the semiconductor substrate or on the semiconductor substrate; And an electrode electrically connected to the conductive region. Wherein the electrode comprises a plurality of finger lines extending in a first direction parallel to the long axis and parallel to each other and extending in a second direction parallel to the minor axis and being connected to the plurality of finger lines, And includes a plurality of bus bars. The overlapped portion and the connecting member extend in the first direction at one side in the second direction.

A solar cell according to an embodiment of the present invention includes: a semiconductor substrate having a major axis and a minor axis intersecting with each other; A conductive type region formed on the semiconductor substrate or on the semiconductor substrate; And an electrode electrically connected to the conductive region. Wherein the electrode includes a plurality of finger lines which are located in a first direction parallel to the major axis and are parallel to each other and which are connected to the plurality of finger lines and extend in a second direction parallel to the minor axis, And includes a plurality of bus bars.

As described above, according to the present embodiment, solar cells having a finger bar formed in a major axis direction and a bus bar formed in a minor axis direction are connected using an overlapping portion and a connecting member, The structure can be connected in a stable manner. In addition, the material cost can be reduced by reducing the electrode formation area. As a result, efficiency and productivity of the solar cell, output of the solar cell panel, and productivity can be improved.

1 is a cross-sectional view illustrating a solar cell panel according to an embodiment of the present invention.
FIG. 2 is a plan view schematically showing a plurality of solar cells included in the solar cell panel shown in FIG. 1 and connected to each other by connecting members.
3 is a cross-sectional view taken along the line III-III of FIG.
4 is a front plan view schematically showing a parent solar cell including a plurality of solar cells that can be included in the solar cell panel of FIG.
FIG. 5 is an exploded plan view schematically showing first and second solar cells, which are manufactured by cutting the parent solar cell shown in FIG. 4 and are connected by a connecting member.
6 is an exploded plan view schematically showing first and second solar cells included in a solar cell panel according to another embodiment of the present invention and connected by a connecting member.
7 is an exploded plan view schematically illustrating first and second solar cells included in a solar cell panel according to a modification of the present invention and connected by a connecting member.
8 is an exploded plan view schematically illustrating first and second solar cells included in a solar cell panel according to another embodiment of the present invention and connected by a connecting member.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, it is needless to say that the present invention is not limited to these embodiments and can be modified into various forms.

In the drawings, the same reference numerals are used for the same or similar parts throughout the specification. In the drawings, the thickness, the width, and the like are enlarged or reduced in order to make the description more clear, and the thickness, width, etc. of the present invention are not limited to those shown in the drawings.

Wherever certain parts of the specification are referred to as " comprising ", the description does not exclude other parts and may include other parts, unless specifically stated otherwise. Also, when a portion of a layer, film, region, plate, or the like is referred to as being "on" another portion, it also includes the case where another portion is located in the middle as well as the other portion. When a portion of a layer, film, region, plate, or the like is referred to as being "directly on" another portion, it means that no other portion is located in the middle.

Hereinafter, a solar cell panel and a solar cell included therein according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a solar cell panel 100 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a solar cell 100 included in the solar cell panel 100 shown in FIG. 1, 1 is a plan view schematically showing a plurality of solar cells 10; The first electrode 42, the second electrode 44, and the connecting member 142 are not shown in FIG. 2 for the sake of clarity and simplicity.

1 and 2, a solar cell panel 100 according to the present embodiment includes a plurality of solar cells 10 including a first solar cell 10a and a second solar cell 10b, And a connecting member 142 connecting the first solar cell 10a and the second solar cell 10b between the overlapped portions OP of the first and second solar cells 10a and 10b. The specific structure of the solar cell 10 and the connecting member 142 will be described later in detail with reference to FIGS. 3 to 5. FIG.

The solar cell panel 100 includes a sealing member 130 that surrounds and seals a plurality of solar cells 10 and a connecting member 142 and a first cover 130 that is positioned on one side of the solar cell 10 on the sealing member 130. [ And a second cover member 120 positioned on the other side of the solar cell 10 on the sealing member 130. [ This will be explained in more detail.

The first cover member 110 is disposed on the seal member 130 (for example, the first seal member 131) to constitute one surface (e.g., a front surface) of the solar cell panel 100, 120 are positioned on the sealing member 130 (in this example, the second sealing member 132) to constitute the other surface (for example, the rear surface) of the solar cell 10. Each of the first cover member 110 and the second cover member 120 may be formed of an insulating material capable of protecting the solar cell 10 from external shock, moisture, ultraviolet rays, or the like. The first cover member 110 may be made of a light-transmitting material that can transmit light, and the second cover member 120 may be made of a sheet made of a light-transmitting material, a non-light-transmitting material, or a reflective material. For example, the first cover member 110 may be composed of a glass substrate having excellent durability and excellent insulation characteristics, and the second cover member 120 may be constituted of a film or a sheet. The second cover member 120 may have a TPT (Tedlar / PET / Tedlar) type or a polyvinylidene fluoride (PET) film formed on at least one side of a base film (e.g., polyethylene terephthalate PVDF) resin layer.

The sealing member 130 includes a first sealing material 131 located on the front surface of the solar cell 10 connected by the connecting member 142 and a second sealing material 132 located on the rear surface of the solar cell 10 can do. The first sealing material 131 and the second sealing material 132 prevent moisture and oxygen from entering and chemically bind each element of the solar cell panel 100. The first and second sealing members 131 and 132 may be made of an insulating material having translucency and adhesiveness. For example, an ethylene-vinyl acetate copolymer resin (EVA), a polyvinyl butyral, a silicon resin, an ester-based resin, an olefin-based resin, or the like may be used for the first sealant 131 and the second sealant 132. A plurality of solar cells 10 connected by the second cover member 120, the second sealing member 132, and the connecting member 142 by a lamination process using the first and second sealing materials 131 and 132, The sealing member 131 and the first cover member 110 are integrated to form the solar cell panel 100. [

However, the present invention is not limited thereto. Accordingly, the first and second sealing members 131 and 132, the first cover member 110, or the second cover member 120 may include various materials other than those described above, and may have various shapes. For example, the first cover member 110 or the second cover member 120 may have various shapes (e.g., a substrate, film, sheet, etc.) or material.

In this embodiment, two solar cells 10 adjacent to each other among the plurality of solar cells 10 are overlapped with each other to form an overlapping portion OP, and overlapping portions OP of the two solar cells 10, And the two solar cells 10 are electrically connected to each other. The plurality of solar cells 10 may be electrically connected in series, parallel, or series-parallel by the connecting member 142. For example, a plurality of solar cells 10 may be sequentially connected in series by a connecting member 142 to constitute a solar cell string composed of one row. At this time, a plurality of solar cells 10 connected by the connecting member 142 may be cut from a mother solar cell to have a major axis and a minor axis.

The solar cell 10 and the connecting member 142 will be described in more detail with reference to FIGS. 3 and 5 together with FIGS. 1 and 2. FIG. 3 to 5, the structure of the electrodes 42 and 44 formed on the solar cell 10 and the connection member 142 considering the structure of the electrodes 42 and 44 are described with reference to FIGS. The structure, and the like will be described in detail.

3 is a cross-sectional view taken along the line III-III of FIG.

3, the solar cell 10 according to the present embodiment includes a semiconductor substrate 12, conductive regions 20 and 30 formed on the semiconductor substrate 12 or on the semiconductor substrate 12, And electrodes 42 and 44 connected to the conductive regions 20 and 30, respectively. That is, the solar cell 10 according to the present embodiment may be a crystalline solar cell based on the semiconductor substrate 12. For example, the conductive regions 20 and 30 may include a first conductive type region 20 and a second conductive type region 30 having different conductivity types, and the electrodes 42 and 44 may include first A first electrode 42 connected to the conductive type region 20 and a second electrode 44 connected to the second conductive type region 30.

The semiconductor substrate 12 may include a base region 14 having a first or second conductivity type including a first or second conductivity type dopant at a relatively low doping concentration. In one example, base region 14 may have a second conductivity type. The base region 14 may be comprised of a single crystalline semiconductor (e.g., a single single crystal or polycrystalline semiconductor, such as single crystal or polycrystalline silicon, particularly monocrystalline silicon) comprising a first or second conductivity type dopant. The solar cell 10 based on the base region 14 or the semiconductor substrate 12 having a high degree of crystallinity and having few defects is excellent in electrical characteristics. At this time, at least one of the front surface and the rear surface of the semiconductor substrate 12 may be provided with a texturing structure or an antireflection structure having irregularities such as a pyramid to minimize reflection.

Each of the conductive regions 20 and 30 includes a first conductive type region 20 located on one side (e.g., a front side) of the semiconductor substrate 12 and having a first conductive type, And a second conductive type region 30 located on the other side (e.g., the other side) and having a second conductive type. The conductive regions 20 and 30 may have a different conductivity type than the base region 14 or may have a higher doping concentration than the base region 14. In this embodiment, the first and second conductivity type regions 20 and 30 are constituted by a doped region constituting a part of the semiconductor substrate 12, so that the junction characteristics with the base region 14 can be improved. At this time, the first conductive type region 20 or the second conductive type region 30 may have a homogeneous structure, a selective structure, or a local structure.

However, the present invention is not limited thereto, and at least one of the first and second conductivity type regions 20 and 30 may be formed separately from the semiconductor substrate 12 on the semiconductor substrate 12. In this case, a semiconductor layer (for example, an amorphous semiconductor layer, an amorphous semiconductor layer, or the like) having a crystal structure different from that of the semiconductor substrate 12 may be formed so that the first or second conductivity type regions 20 and 30 can be easily formed on the semiconductor substrate 12, A microcrystalline semiconductor layer, or a polycrystalline semiconductor layer, for example, an amorphous silicon layer, a microcrystalline silicon layer, or a polycrystalline silicon layer).

One of the first and second conductivity type regions 20 and 30 having a conductivity type different from that of the base region 14 constitutes at least a part of the emitter region. The other of the first and second conductivity type regions 20 and 30 having the same conductivity type as the base region 14 constitutes at least a part of a surface field region. For example, in this embodiment, the base region 14 and the second conductivity type region 30 may have a second conductivity type and an n-type, and the first conductivity type region 20 may have a p-type. Then, the base region 14 and the first conductive type region 20 form a pn junction. When the pn junction is irradiated with light, the electrons generated by the photoelectric effect move toward the rear side of the semiconductor substrate 12 and are collected by the second electrode 44, and the holes move toward the front side of the semiconductor substrate 12 1 electrode 42. In this case, Thereby, electric energy is generated. Then, holes having a slower moving speed than electrons can be moved to the front surface of the semiconductor substrate 12, not the rear surface thereof, thereby improving the efficiency. However, the present invention is not limited thereto, and it is also possible that the base region 14 and the second conductivity type region 30 have the p-type and the first conductivity type region 20 has the n-type. The base region 14 may be opposite to the second conductivity type region 30 and have the same conductivity type as the first conductivity type region 20.

The first or second conductivity type dopant may be n-type or p-type. As the p-type dopant, a group III element such as boron (B), aluminum (Al), gallium (Ga), or indium (In) can be used. In the case of the n-type, Group 5 elements such as phosphorus (P), arsenic (As), bismuth (Bi) and antimony (Sb) can be used. For example, the p-type dopant may be boron (B) and the n-type dopant may be phosphorus (P).

The first passivation film 22 and / or the antireflection film 22 are formed on the front surface of the semiconductor substrate 12 (more precisely, on the first conductive type region 20 formed on the front surface of the semiconductor substrate 12) (For example, contact). A second passivation film 32 serving as a second insulating film is formed on the rear surface of the semiconductor substrate 12 (more precisely on the second conductive type region 30 formed on the rear surface of the semiconductor substrate 12) , Contact). The first passivation film 22, the antireflection film 24, and the second passivation film 32 may be formed of various insulating materials. In one example, the first passivation film 22, the anti-reflection film 24 or the second passivation film 32 is a silicon nitride film, a silicon nitride film containing hydrogen, silicon oxide, silicon nitride oxide, aluminum oxide film, a silicon carbide film, MgF ₂ , ZnS, TiO _2, and CeO ₂ , or a multilayer film structure in which two or more films are combined. However, the present invention is not limited thereto.

The first electrode 42 is electrically connected to the first conductivity type region 20 through the opening passing through the first insulating film and the second electrode 44 is electrically connected to the first conductive type region 20 through the second insulating film. (For example, by contact formation) to the second conductivity type region 30 through the opening. The first and second electrodes 42 and 44 are made of various conductive materials (for example, metal) and may have various shapes. The shape of the first and second electrodes 42 and 44 and the position and shape of the connecting member 142 considering the shape of the first and second electrodes 42 and 44 will be described later in more detail.

As described above, in this embodiment, one solar cell 100a is cut to manufacture a plurality of solar cells 10, which are used as a unit solar cell. Hereinafter, a solar cell 100a including a plurality of solar cells 10 will be described with reference to FIG. 1 to FIG. 3 together with FIGS. 1 to 3, and the solar cell 100a is cut The connection structure of the plurality of solar cells 10 manufactured will be described in detail.

FIG. 4 is a front plan view schematically showing a parent solar cell 100a including a plurality of solar cells 10 that can be included in the solar cell panel 100 of FIG. 1, FIG. 5 is a front plan view 1 is a development plan view schematically showing first and second solar cells 10a and 10b manufactured by cutting a solar cell 100a and connected by a connecting member 142. FIG. In FIGS. 4 and 5, the semiconductor substrate 12 and the first electrode 42 are mainly shown for simplicity and clarity.

5A shows the front surface of the semiconductor substrate 12 of the first solar cell 10a and the first electrode 42 formed thereon and FIG. A connecting member 142 positioned between the overlapping portions OP of the first solar cell 10a and the second solar cell 10b is shown in FIG. The backside of the substrate 12 and the second electrode 44 formed thereon are shown. The connecting member 142 is placed on the overlapping portion OP of the first solar cell 10a shown in Figure 5 (a) and the overlapping portion OP of the second solar cell 10b shown in Figure 5 (c) The first and second solar cells 10a and 10b are connected to each other via the connecting member 142 when the first solar cell OP is placed on the overlapping portion OP and the connecting member 142 of the first solar cell 10a .

Referring to FIG. 4, in this embodiment, one mother solar cell 100a is cut along the cutting line CL to manufacture a plurality of solar cells 10. FIG. Each of the plurality of solar cells 10 serving as a unit solar cell functions as one solar cell. When the parent solar cell 100a is separated into a plurality of solar cells 10, the output power loss (cell to module loss) generated when the plurality of solar cells 10 is connected to the solar cell panel 100, CTM loss can be reduced.

More specifically, the output loss has a value multiplied by the square of the current in each solar cell 10, and the output loss of the solar cell panel 100 including a plurality of solar cells 10 is The value obtained by multiplying the square of the current of each solar cell 10 by the resistance multiplied by the number of solar cells 10. However, in the current of each solar cell 10, there is a current generated by the area of the solar cell 10 itself, and when the area of the solar cell 10 increases, the current also becomes larger and when the area of the solar cell 10 becomes smaller The current becomes smaller.

Therefore, when the solar cell panel 100 is formed using the solar cell 10 manufactured by cutting the parent solar cell 10, the current of the solar cell 10 decreases in proportion to the area, The number increases inversely. For example, when there are four solar cells 10 manufactured from the parent solar cell, the current in each solar cell 10 is reduced to one quarter of the current of the parent solar cell, The number of solar cells is four times as large. Since the current is reflected in square and the number is reflected as it is, the output loss value is reduced to one quarter. Accordingly, the output loss of the solar cell panel 100 according to the present embodiment can be reduced.

In this embodiment, the parent solar cell 100a is manufactured as in the prior art, and then the solar cell is cut to form the solar cell 10. According to this, the solar cell 10 can be manufactured by manufacturing the solar cell 100a using the existing equipment, the optimized design, and the like, and then cutting the solar cell 100a. As a result, facility burden and process cost burden are minimized. On the other hand, if the size of the parent solar cell 100a is reduced, there is a burden of replacing the used equipment or changing the setting.

In general, the parent solar cell 100a or its semiconductor substrate 12 is fabricated from a roughly circular ingot and is formed in a circular, square, or similar manner in two mutually orthogonal directions (e.g., finger lines 42a, 44a extend and the direction in which the bus bar electrodes 42b, 44b extend) are the same or substantially the same. For example, the semiconductor substrate 12 of the parent solar cell 100a may have an octagonal shape having inclined portions 12a and 12b at four corner portions in an approximate square shape. With such a shape, a semiconductor substrate having the largest area from the same ingot can be obtained. However, the present invention is not limited thereto, and the number of solar cells 10 manufactured in one parent solar cell 100a may be variously modified. Thus, the parent solar cell 100a has a symmetrical shape and can have the same distance between the maximum lateral width (the width across the center of the semiconductor substrate) and the maximum vertical width (the vertical width across the center of the semiconductor substrate).

In this embodiment, the solar cell 10 is formed by cutting the parent solar cell 100a along the cutting line CL so that the solar cell 10 or the semiconductor substrate 12 included therein has a long axis and a short axis Shape.

4 and 5, in this embodiment, the first electrodes 42 located on one side of the semiconductor substrate 12 are positioned in a first direction (y-axis direction in the figure) parallel to the long axis and parallel to each other A first bus bar 42b formed in a second direction (x-axis direction in the figure) parallel to the minor axis and connected to the plurality of first finger lines 42a, . At this time, the first bus bar 42b may include a plurality of first bus bars 42b spaced apart from each other in the first direction.

The first finger lines 42a may be spaced apart from each other with a uniform width and pitch. Here, the first finger lines 42a may be formed parallel to each other in the first direction parallel to the long axis, and may be parallel to the long axis edge of the solar cell 10.

At least one of the plurality of first bus bars 42b may be formed across the inner portion of the first finger line 42a. The movement path of the carriers collected by the first finger line 42a can be reduced by the plurality of first bus bars 42b. At this time, at least the width of the portion of the bus bar 42b (i.e., the connecting electrode portion 420) located in the overlapping portion OP in the first direction is smaller than the width of the first finger line 42a in the second direction It can be big. Accordingly, the connection member 142 and the plurality of bus bars 42b can have a sufficient connection area. The present invention is not limited thereto. Thus, the width of the first bus bar 42b may be equal to or less than the width of the first finger line 42a.

 In this embodiment, the number of the first bus bars 42b is sufficiently secured by 6 or more (more specifically, 6 to 14, for example, 6 to 12) to minimize the movement path of the carrier have. Since the connecting member 142 is not directly connected to the first bus bar 42b except for one side where the connecting member 142 is located, The shading loss can be minimized by providing only the line portion 421. [ For example, the first bus bar 42b may consist entirely of a line portion 421. [ However, the present invention is not limited thereto, and the first bus bar 42b may have a pad portion. 8, a pad portion formed at a portion connected to the connecting member 142 at the first bus bar 42b will be described in detail.

The first finger line 42a and the first bus bar 42b of the first electrode 42 may all be formed through the first insulating film. However, the present invention is not limited thereto. As another example, the first finger line 42a of the first electrode 42 may be formed through the first insulating film, and the first bus bar 42b may be formed on the first insulating film.

In FIG. 4, a frame line 42c that connects ends of a plurality of first finger lines 42a is disposed at a portion parallel to the slopes 12a and 12b, thereby effectively collecting carriers. This edge line 42c may have the same or similar width as the first finger line 42a and may be made of the same material as the first finger line 42a. However, it is also possible not to include the border line 42c.

The second electrode 44 located on the other side of the semiconductor substrate 12 is connected to the first finger line 42a of the first electrode 42 and the first finger line 42a corresponding to the first bus bar 42b, And a second bus bar 44b. And the second electrode 44 may further include a rim line 44c corresponding to the rim line 42c of the first electrode 42. [ The content of the first electrode 42 may be applied to the second electrode 44 and the content of the first passivation film 22 and the antireflection film 24 associated with the first electrode 42 may be applied to the second electrode 44. [ Is applied directly to the second passivation film 32 with respect to the second electrode 44 and the content of the first conductivity type region 20 associated with the first electrode 42 is applied to the second conductive type 32, Area 30 as shown in FIG. The width and pitch of the first finger line 42a, the first bus bar 42b and the frame line 42c of the first electrode 42 are set to the second finger line 44a of the second electrode 44, The second bus bar 44b and the edge line 44c may be the same or different from each other.

However, the present invention is not limited thereto. It is also possible to form an electrode which does not include the finger lines 42b and 44b or has a shape different from that of the finger lines 42a and 44a described above. In addition, unlike the above, it is also possible that the planar shapes of the first electrode 42 and the second electrode 44 are completely different from each other or have no similarity, and various other modifications are possible.

In this embodiment, the first and second electrodes 42 and 44 of the solar cell 10 have a certain pattern, so that the solar cell 10 can receive light from the front surface and the rear surface of the semiconductor substrate 12, And has a bi-facial structure. Thus, the amount of light used in the solar cell 10 can be increased to contribute to the improvement of the efficiency of the solar cell 10. However, the present invention is not limited thereto, and various modifications are possible.

In this embodiment, the plurality of solar cells 10 located in the parent solar cell 100a may extend along the first direction which is the longitudinal direction of the finger lines 42a and 44a and may be located in the second direction. The cutting line CL is parallel to the first direction which is the longitudinal direction of the finger lines 42a and 44a and can intersect with the second direction which is the extending direction of the bus bars 42b and 44b. The overlapping portion OP and the connecting member 142 are extended in the first direction which is the longitudinal direction of the finger lines 42a and 42b at one side in the second direction parallel to the extending direction of the bus bars 42b and 44b . That is, one side of the first solar cell 10a in the second direction overlaps the other side of the second solar cell 10b in the second direction, forming the overlapping portion OP, and the overlapping portion OP Is elongated along the longitudinal direction of the finger lines 42a, 44a or the long axis direction of the solar cell 10. The connecting member 142 is positioned over the plurality of bus bars 42b and 44b spaced from each other in the overlapped portion OP of the neighboring first and second solar cells 10a and 10b, (10) are electrically connected. Then, the solar cells 10 having the short axis and the long axis can be connected in the long axis direction, and the connection area can be sufficiently secured to stably connect the solar cells. However, the present invention is not limited thereto.

More specifically, in the present embodiment, the connecting member 142 extends in a direction crossing the plurality of bus bars 42b and 44b (that is, the connecting electrode portions 420 spaced from each other) Direction) in the longitudinal direction. For example, the connecting member 142 may be composed of a single connecting portion 142a having a uniform shape and extending in a long length. Then, the connection by the connecting member 142 can be stably performed using a simple structure. The connecting member 142 is connected to the first bus bar 42b of the first electrode 42 of the first solar cell 10a and the second bus bar 42b of the second solar cell 10b of the second solar cell 10b And the other part of the first and second bus bars 42b and 44b are formed on the other side of the plurality of second bus bars 44b of the second bus bar 44b, .

At this time, the connecting member 142 is disposed above the first insulating film of the first solar cell 10a and the second insulating film of the second solar cell 10b between the plurality of bus bars 42b, 44b in the first direction, (For example, a contact) between the electrodes. Since the connecting member 142 has excellent adhesion with the first and second insulating films, the first and second solar cells 10a and 10b can be stably connected.

In this embodiment, the first and second finger lines 42a and 44a are provided on the overlapping portion OP so that the connection member 142 can be connected to the first and second finger lines 42a and 44a. In this case, the connection areas of the first and second electrodes 42 and 44 and the connection member 142 are maximized and they can be stably connected. However, the present invention is not limited thereto. Other examples will be described later in detail with reference to FIG.

The connection structure of the neighboring two solar cells 10 may be successively repeated in two adjacent solar cells 10 to form a solar cell string composed of a plurality of solar cells 10.

The connecting member 142 may include an adhesive material. As the adhesive material, various materials capable of electrically and physically connecting the two solar cells 10 with electrical conductivity and adhesive properties may be used. For example, the connecting member 142 may be formed of a conductive adhesive layer, solder, or the like.

When the finger lines 42a and 44a are formed along the long axis, the lengths of the finger lines 42a and 44a are sufficiently long so that carriers can be stably collected and the movement distance of the carriers can be minimized by the plurality of bus bars 42b and 44b. The connection member 142 is positioned over a part of the plurality of bus bars 42b and 44b to improve the stability of the electrical connection between the plurality of bus bars 42b and 44b and the connection member 142, Connection is possible. On the other hand, unlike in the present embodiment, when the finger line is located in the minor axis direction, the bus bar or the connecting member is positioned at only one end thereof, and the movement path of the collected collected carriers is increased in the part far away from the bus bar or the connecting member . Further, unlike the present embodiment, the use of an interconnector such as a ribbon can complicate the manufacturing process.

The solar cell 10 including the finger lines 42a and 44a formed in the major axis direction and the bus bars 42b and 44b formed in the minor axis direction can be used as the overlapped portion OP and the connecting member 142 So that the plurality of solar cells 10 can be stably connected with a simple structure while improving the collection efficiency of the carriers. Since the bus bars 42b and 44b are spaced apart from each other in the first direction in which the connecting member 142 extends, the bus bar having a relatively thick width is extended in the same direction as the connecting member 142 The formation area can be reduced as compared with the case of forming. Thus, the material cost can be reduced. Thus, efficiency of the solar cell 10, output of the solar cell panel 100, and productivity can be improved.

Hereinafter, a solar cell panel according to another embodiment of the present invention will be described in detail. Detailed descriptions will be omitted for the same or extremely similar parts as those described above, and only different parts will be described in detail. It is also within the scope of the present invention to combine the above-described embodiments or variations thereof with the following embodiments or modifications thereof.

6 is an exploded plan view schematically showing first and second solar cells included in a solar cell panel according to another embodiment of the present invention and connected by a connecting member.

6, in this embodiment, the connection member 142 located in the overlapping portion OP corresponds to the plurality of bus bars 42b and 44b (more specifically, the plurality of connection electrode portions 420) And may include a plurality of partially connected connection portions 142a. Thus, the connection portion 142a is positioned only at the portion where the connection is substantially made, thereby reducing the material cost.

The connecting member 142 may further include an adhesive member 142b formed of a material different from the connecting portion 142a between the plurality of connecting portions 142a. In one example, the adhesive member 142b has a shape connecting between the two connecting portions 142a, and may have a smaller width than the connecting portion 142a. The connecting portion 142a is made of a material having good electrical conductivity and adhesive property for electrical connection and the bonding member 142b is made of an adhesive material having electrical conductivity lower than that of the connecting portion 142a or having no electrical conductivity Can be used to reduce material costs and improve adhesion properties. Further, the width of the adhesive member 142b can be relatively reduced, thereby further reducing the material cost.

As the material of the adhesive member 142b, various known adhesive materials, for example, an adhesive material composed of a resin, may be used. For example, acrylic-based or urethane-based adhesive materials can be used. However, the adhesive member 142b is not an essential constitution, and in one variant, as shown in Fig. 7, the connecting member 142 is provided only with a plurality of connecting portions 142a which are separated from each other without the adhesive member 142b .

8 is an exploded plan view schematically illustrating first and second solar cells included in a solar cell panel according to another embodiment of the present invention and connected by a connecting member.

8, in this embodiment, at one end of each of the plurality of bus bars 42a and 44b, a portion connected to the connecting member 142 has a larger width than the other portion (for example, the line portion 421) Pad portions 420b and 440b. According to this, the connection area with the connecting member 142 can be increased to improve the stability of the electrical connection.

In this embodiment, the finger lines 42a and 44a may not be positioned within the overlapping portion OP. The bus bars 42b and 44b on one side where the overlapping portion OP is located are provided with the finger lines 42a and 44a positioned closest to the aforementioned one of the plurality of finger lines 42a and 44a Lines 420a and 440a) of the solar cell 10, as shown in Fig. According to this, the finger lines 42a and 44a are removed from the overlapped portion OP, which is substantially unlikely to contribute to the photoelectric conversion, so that the formation area of the first and second electrodes 42 and 44 Can be reduced. Thus, efficiency and productivity of the solar cell 100 can be improved, and the output and productivity of the solar cell 100 can be further improved.

On the other hand, on the opposite side of the overlapping portion OP, the bus bars 42b and 44b may be located on the same line as the finger lines 42a and 44a positioned closest to the one of the plurality of finger lines 42a and 44a have. Accordingly, the finger lines 42a and 44a and the bus bars 42b and 44b are sufficiently formed in the portion directly involved in the photoelectric conversion, thereby effectively collecting the carriers. However, the present invention is not limited to this, and the bus bars 42b and 44b may protrude more or less than the finger lines 42a and 44a on the opposite side of the overlapping portion OP.

In FIG. 8, bus bars 42b and 44b having pads 420b and 440b and an overlapping part OP having no finger lines 42a and 44a are illustrated. However, the present invention is not limited thereto. Bus bars 42b and 44b having pad portions 420b and 440b and at least one of overlapping portions OP not having finger lines 42a and 44a may be provided. Although the connection member 142 has a structure as shown in FIG. 5, it may have a structure as shown in FIG. 6 and FIG.

Features, structures, effects and the like according to the above-described embodiments are included in at least one embodiment of the present invention, and the present invention is not limited to only one embodiment. Further, the features, structures, effects, and the like illustrated in the embodiments may be combined or modified in other embodiments by those skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

100: Solar panel
10: Solar cell
142:
42a: Finger line
42b: bus bar

Claims (20)

A plurality of solar cells including first and second solar cells; And
And a connecting member for connecting the first solar cell and the second solar cell between the overlapped portions of the first and second solar cells,
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Wherein each of the plurality of solar cells comprises: a semiconductor substrate having a major axis and a minor axis intersecting with each other; A conductive type region formed on the semiconductor substrate or on the semiconductor substrate; And an electrode electrically connected to the conductive region,
Wherein the electrode comprises a plurality of finger lines extending in a first direction parallel to the long axis and parallel to each other and extending in a second direction parallel to the minor axis and being connected to the plurality of finger lines, A plurality of bus bars,
Wherein the overlapping portion and the connecting member extend in the first direction from one side in the second direction. The method according to claim 1,
Wherein the connecting member is formed between at least the overlapping portions of the first and second solar cells at least over part of the plurality of bus bars to electrically connect the first and second solar cells. The method according to claim 1,
Wherein the connecting member has a portion located on the insulating film of the first or second solar cell between the plurality of bus bars in the first direction. The method according to claim 1,
Wherein the plurality of bus bars are composed of a line portion having a uniform width at a portion other than at least the overlap portion. The method according to claim 1,
Wherein the plurality of bus bars include a pad portion at a portion connected to the connecting member at one end thereof. The method according to claim 1,
Wherein at least one of the plurality of bus bars is formed across an inner portion of the finger electrode. The method according to claim 1,
Wherein a width of the bus bar in the first direction in the overlap portion is larger than a width of the finger line in the second direction. The method according to claim 1,
Wherein the finger line is not positioned within the overlapping portion. The method according to claim 1,
Wherein the bus bar is further protruded toward an edge of the solar cell than a finger line positioned closest to the one of the plurality of finger lines on a side where the overlap portion is located. 10. The method of claim 9,
And the bus bar on the opposite side of the overlapping portion is located on the same line as the finger line positioned closest to the one of the plurality of finger lines. 3. The method of claim 2,
Wherein the connecting member has a shape extending in a direction intersecting the plurality of bus bars across the plurality of bus bars in the overlapping portion. 3. The method of claim 2,
Wherein the connecting member located in the overlapping portion includes a plurality of connecting portions that are partially located to correspond to the plurality of bus bars. 13. The method of claim 12,
And a bonding member composed of a material different from the connecting portion between the plurality of connecting portions. A semiconductor substrate having a major axis and a minor axis intersecting each other;
A conductive type region formed on the semiconductor substrate or on the semiconductor substrate; And
And an electrode electrically connected to the conductive region,
Wherein the electrode includes a plurality of finger lines which are located in a first direction parallel to the major axis and are parallel to each other and which are connected to the plurality of finger lines and extend in a second direction parallel to the minor axis, A solar cell comprising a plurality of bus bars. 15. The method of claim 14,
Wherein the plurality of bus bars are constituted by line portions having a uniform width. 15. The method of claim 14,
Wherein the plurality of bus bars are located at one end portion thereof. 15. The method of claim 14,
Wherein at least one of the plurality of bus bars is formed across an inner portion of the finger electrode. 15. The method of claim 14,
Wherein a width of the bus bar in the first direction is larger than a width of the finger line in the second direction. 15. The method of claim 14,
Wherein the bus bar is further protruded toward an edge of the solar cell than a finger line located nearest to the one of the plurality of finger lines. 20. The method of claim 19,
Wherein the bus bar on the other side of the semiconductor substrate is located on the same line as the finger line positioned closest to the one of the plurality of finger lines.

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