KR102397996B1 - Solar cell panel and method for manufacturing the same - Google Patents

Abstract

A solar cell panel according to an embodiment of the present invention includes a central region in which a sealing material for sealing the solar cell is provided, and an outer region in which a reinforcement region positioned outside the central region and having a thickness greater than the central region is provided.

Description

Solar cell panel and manufacturing method thereof

The present invention relates to a solar cell panel and a method for manufacturing the same, and more particularly, to a solar cell panel with improved structure and process and a method for manufacturing the same.

Since the solar cell has to be exposed to the external environment for a long time, it is manufactured in the form of a solar cell panel including the solar cell, a sealing material, and a cover member by a packaging process for protecting the solar cell.

A solar cell panel including various members as described above is manufactured by a lamination process that applies heat and pressure, and a problem in which a solar cell or a cover member is broken or damaged may occur in a portion that receives a large load due to the pressure applied during the lamination process. could In addition, the sealing material may flow out from the edge portion of the solar cell panel due to the pressure applied during the lamination process, so that the thickness of the sealing material at the edge portion may be significantly thinner than other portions (eg, the central portion). Accordingly, the sealing material may not have a sufficient thickness to implement a desired sealing characteristic at the edge portion of the solar cell panel. This problem may occur more seriously when the cover member includes the glass substrate, particularly, when the cover members positioned on both surfaces include the glass substrate.

In order to prevent this problem, a method of reducing the temperature and pressure during the lamination process and increasing the process time was used in the prior art. However, this method increases the time and cost of the lamination process, and even by this method, there is a problem in that the frequency of breakage or damage to the solar cell or the cover member is not significantly reduced. As another example of the prior art, as in International Patent Application Laid-Open No. WO2015/182755, when a rear sealing film thicker than the front sealing film is used, material cost, process time, etc. may be increased by using the overall thick rear sealing film.

Patent Document 1: International Patent Publication No. WO2015/182755 (Title of the Invention: Method of Manufacturing Solar Cell Module and Solar Cell Module)

An object of the present invention is to provide a solar cell panel capable of improving the productivity of the solar cell panel and reducing the defect rate, and a method for manufacturing the same.

In particular, the present invention does not significantly increase the amount of the sealing material used, thereby reducing material costs while reducing the lamination process time, and providing a solar cell panel capable of effectively preventing damage to the solar cell or the cover member during the lamination process, and a method for manufacturing the same want to In addition, the present invention provides a solar cell panel that allows the edge portion of the solar panel to have a sufficient thickness to implement a desired sealing characteristic in consideration of external leakage of a sealing material that may occur at the edge portion of the solar cell panel in the lamination process; An object of the present invention is to provide a method for preparing the same.

A solar cell panel according to an embodiment of the present invention includes a central region in which a sealing material for sealing the solar cell is provided, and an outer region in which a reinforcement region positioned outside the central region and having a thickness greater than the central region is provided. Alternatively, an encapsulant surrounding the solar cell includes a central region and an outer region provided with a thick film region positioned outside the central region and having a greater thickness than the central region. Here, the encapsulant may include a first encapsulant positioned on one surface of the solar cell and a second encapsulant positioned on the other surface of the solar cell. In this embodiment, the first cover member positioned on the first sealing material and the second cover member positioned on the second sealing material may each include a glass substrate.

In the present embodiment, the outer region may further include an edge region located outside the reinforcement region and having an edge having a smaller thickness than the reinforcement region. For example, the thickness at the edge of the sealing material may be equal to or smaller than the thickness of the region. In addition, the thickness of the reinforcing region may be greater than 30 μm or more than the thickness of the central region, or a ratio of a thickness difference between the reinforcing region and the central region to the thickness of the central region may be 10% or more.

In this embodiment, the solar cell includes a plurality of solar cells including an outer solar cell positioned outside and an inner solar cell positioned inside the outer solar cell, wherein the reinforcement region overlaps at least a portion of the outer solar cell. and positioned so as not to overlap the inner solar cell.

The reinforcement region may include a portion whose thickness gradually increases toward the edge of the outer solar cell. The edge region may gradually decrease in thickness toward the edge of the solar panel.

Correspondingly, the solar cell panel may include an outer portion positioned outside the central portion and provided with a reinforcing portion having a thickness greater than that of the central portion. In addition, the outer portion may further include an edge portion positioned outside the reinforcing portion and having an edge having a smaller thickness than the reinforcing portion.

In this embodiment, the central region may have a larger area than each of the reinforcement region and the outer region.

For example, the solar cell includes a plurality of solar cells that are electrically connected in one direction to form a solar cell string, and the outer region or the reinforcing region is located on both sides of the intersecting direction intersecting the one direction at both edges in one direction. can be followed for a long time. However, the present invention is not limited thereto, and the outer region or the reinforcing region may be formed in a different direction or may be formed at a different position.

The solar cell may include a plurality of solar cells connected in one direction by a plurality of wiring materials. The first width of the wiring member may be 250 μm to 500 μm, or the wiring member may include a circular or rounded portion. The number of the wiring members may be 6 to 33.

In the method of manufacturing a solar cell panel according to an embodiment of the present invention, a solar cell, first and second sealing materials, and first and second cover substrates are laminated to form a laminate structure, and heat and pressure are applied thereto to laminate the solar cell. In this case, at least one of the first and second sealing materials includes a base portion and a reinforcing portion having an overlapping portion positioned on the base portion and overlapping at least a portion of the solar cell. Alternatively, the encapsulant surrounding the solar cell is provided with a central portion and a thick film portion positioned outside the central portion and having a greater thickness than the central portion. Thereby, at least one of the first and second sealants is constituted of the reinforcing sealant having a greater thickness in the second region or thick film portion in which the base portion and the reinforcing portion are located together than in the first region or the central portion in which the base portion is located. Here, the first sealing material and the first cover member are positioned on one surface of the solar cell, and the second sealing material and the second cover member are positioned on the other surface of the solar cell. In this embodiment, each of the first cover member and the second cover member may include a glass substrate.

Accordingly, after the laminating step, the sealing material positioned between the first cover member and the second cover member comprises a central region and an outer region provided with a reinforcing region located outside the central region and having a thickness greater than that of the central region. may include Alternatively, the solar cell panel may include an outer portion disposed outside the central portion and provided with a reinforcing portion having a thickness greater than that of the central portion.

For example, the ratio of the width of the overlapping portion to the width of the solar cell may be 10% or more, or the width of the reinforcing portion may be 5 cm or more.

In the reinforcing encapsulant, the first region may have a larger area than the second region, and in the reinforcing encapsulant, the reinforcing portion may be located at least at an edge or a corner portion of the solar cell panel.

Here, the base portion may have a first thickness, the reinforcing portion may have a second thickness, and the second thickness may be less than the first thickness.

In the present embodiment, in the reinforcing sealant, the base portion and the reinforcing portion are made of the same material to constitute an integral structure, so that the reinforcing sealant may have a single body. Alternatively, in the reinforcing sealant, the reinforcing portion may have a different material from the base portion or may be formed separately and attached to or overlying the base portion. In this case, the reinforcing portion may have lower hardness and higher elasticity than the base portion.

According to the present embodiment, a problem of reducing the thickness of the encapsulant that may occur at the edge of the solar cell panel may be prevented by providing a reinforcement region in which the encapsulant has a thicker thickness than the central region at the edge portion of the solar cell panel. Accordingly, the solar cell panel may have excellent sealing properties as a whole, and damage to the solar cell and the cover member that may occur in a portion where pressure is concentrated during the lamination process may be prevented. Thereby, the reliability of a solar cell panel can be improved and the defect rate at the time of manufacture of a solar cell panel can be reduced.

In addition, since the lamination process can be performed at a high temperature and/or a sufficient pressure by the reinforcing part, the process time of the lamination process can be effectively shortened. On the other hand, leakage of the sealing material to the outside during the lamination process is not a major problem, and the central region of the sealing material to which a relatively small pressure is applied has a relatively small thickness, so that the material cost of the sealing material can be minimized. Thereby, productivity at the time of manufacturing a solar cell panel can be improved significantly.

1 is a perspective view schematically illustrating a solar cell panel according to an embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view taken along line II-II of FIG. 1 .
3 is a cross-sectional view illustrating an example of a solar cell that may be included in the solar cell panel shown in FIG. 1 .
FIG. 4 is a schematic plan view of the solar cell shown in FIG. 3 .
5 is a schematic plan view illustrating a solar cell panel according to an embodiment of the present invention.
6 is a cross-sectional view taken along line VI-VI of FIG. 5 .
7 is a schematic plan view illustrating a solar cell panel according to various modifications of the present invention.
8A to 8C are diagrams schematically illustrating a method of manufacturing a solar cell panel according to an embodiment of the present invention.
9 is a schematic plan view illustrating a solar cell and a sealing material having a base portion and a reinforcing portion applicable to a solar cell panel according to an embodiment of the present invention.
10 is a cross-sectional view illustrating a sealing material having a base portion and a reinforcing portion applicable to a solar cell panel according to another embodiment of the present invention.
11 is a photograph of solar cell panels according to Examples and Comparative Examples.
12 is a cross-sectional view illustrating a solar cell panel according to another embodiment of the present invention.
13 is a cross-sectional view illustrating a solar cell panel according to another embodiment of the present invention.
14 is a cross-sectional view illustrating a solar cell panel according to another embodiment of the present invention.
15 is a front plan view illustrating a solar cell included in a solar cell panel and a wiring member connected thereto according to another embodiment of the present invention.
16 is a partial cross-sectional view of the solar cell shown in FIG. 15 and a wiring member connected thereto.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, it goes without saying that the present invention is not limited to these embodiments and may be modified in various forms.

In the drawings, in order to clearly and briefly describe the present invention, the illustration of parts irrelevant to the description is omitted, and the same reference numerals are used for the same or extremely similar parts throughout the specification. In addition, in the drawings, the thickness, width, etc. 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 the bars shown in the drawings.

And, when a certain part "includes" another part throughout the specification, other parts are not excluded unless otherwise stated, and other parts may be further included. Also, when a part such as a layer, film, region, plate, etc. is said to be “on” another part, it includes not only the case where the other part is “directly on” but also the case where another part is located in the middle. When a part, such as a layer, film, region, or plate, is "directly above" another part, it means that no other part is located in the middle.

1 is a perspective view schematically illustrating a solar cell panel according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view taken along line II-II of FIG. 1 . 1 and 2 , only the shape of the sealing material 130 and the solar cell panel 100 including the same is schematically illustrated, and the specific shape will be described in detail later with reference to FIG. 6 .

1 and 2 , the solar cell panel 100 according to the present embodiment includes a solar cell 10 , a first solar cell 10 sealing the solar cell 10 , and positioned on one surface and the other surface of the solar cell 10 . The sealant 130 including the first and second sealants 131 and 132 , the first cover member 110 positioned on the first sealant 131 and including a glass substrate, and the second sealant 132 positioned on the and a second cover member 120 including a glass substrate. In this case, the sealing material 130 is located outside the central region (reference numeral CA in FIG. 6, hereinafter the same) and the central region CA and has a greater thickness than the central region CA (refer to FIG. 6 ). It includes an outer region (reference numeral EA in FIG. 6, hereinafter the same) provided with reference numeral EA1, hereinafter the same. This will be described in more detail.

At this time, the solar cell 10 includes a photoelectric conversion unit generating electrons and holes by the incident light, and electrodes (reference numerals 42, 44, hereinafter the same) may be included. The photoelectric conversion unit and the electrodes 42 and 44 may have various structures. For example, the solar cell 10 may have a bi-facial structure. An example of the solar cell 10 applicable to the solar cell panel 100 according to an embodiment of the present invention will be described in detail later with reference to FIGS. 3 and 4 .

The first cover member 110 is positioned on the first encapsulant 131 to configure the front surface of the solar cell panel 100 , and the second cover member 120 is positioned on the second encapsulant 132 to form the solar cell. It constitutes the rear surface of the panel 100 . Each of the first cover member 110 and the second cover member 120 may be made of an insulating material capable of protecting the solar cell 10 from external impact, moisture, ultraviolet rays, and the like.

For example, each of the first cover member 110 and the second cover member 120 may be a glass substrate having excellent durability, insulating properties, moisture resistance, light transmittance, and the like. Then, the glass substrate is located on both sides of the solar cell panel 100, can have excellent transmittance from both sides, can have high durability due to high strength, and have excellent moisture resistance, UV resistance, insulation properties, etc. can Accordingly, it is possible to physically and chemically protect the solar cell 10 stably.

In this embodiment, a plurality of solar cells 10 may be electrically connected in series, parallel, or series-parallel by the interconnector 142 and/or the bus ribbon 145 . For example, a plurality of solar cells 10 are connected in a first direction (y-axis direction in the drawing) by an interconnector 142 to constitute a solar cell string S consisting of one row, A plurality of solar cell strings S may be positioned in a second direction (x-axis direction of the drawing) intersecting the first direction. In addition, the bus ribbon 145 is disposed at the end of the solar cell string S in a direction crossing it to connect the adjacent solar cell strings S or prevent electricity from flowing backward through the solar cell strings S. It can be connected to a junction box (not shown). For example, the bus ribbon 145 may alternately connect both ends of the interconnector 142 of the solar cell string S to connect the solar cell string S in series. However, the present invention is not limited thereto, and the bus ribbon 145 may have various arrangements and connection structures.

As the in-connector 142 and/or the bus ribbon 145 , various structures and shapes capable of connecting the solar cell 10 such as a ribbon and a wire may be applied. For example, the interconnector 142 and/or the bus ribbon 145 may be electrically and physically connected to the solar cell 10 or the interconnector 142 using a tabbing process using a solder material. Alternatively, the interconnector 142 and/or the bus ribbon 145 may be a conductive film made of a conductive adhesive material. However, the present invention is not limited thereto. For example, the solar cell panel 100 may include only one solar cell 10 , and the plurality of solar cells 10 are electrically connected to each other by connecting members other than the interconnector 142 and the bus ribbon 145 . may be connected.

For example, the interconnector 142 connects the first electrode 42 located on the front surface of one solar cell 10 and the second electrode 44 located on the rear surface of the adjacent solar cell 10 . can be formed. However, the present invention is not limited thereto, and adjacent solar cells 10 may be connected in other forms.

The encapsulant 130 may include a first encapsulant 131 positioned on the front surface of the solar cell 10 electrically connected to each other, and a second encapsulant 132 positioned at the rear face of the solar cell 10 electrically. can 6 illustrates that the first sealing material 131 and the second sealing material 132 have a certain boundary, but in the lamination process, the first sealing material 131 and the second sealing material 132 are integrated to form the sealing material 130 . Therefore, the boundary between the first sealing material 131 and the second sealing material 132 may not be clear.

The sealing material 130 prevents moisture and oxygen from entering the solar cell 10 and chemically bonds each element of the solar cell panel 100 . The sealing material 130 includes an insulating material having light-transmitting properties and adhesive properties as a base material. For example, the sealing material 130 may include ethylene vinyl acetate resin (EVA), polyvinyl butyral (PVB), silicon resin, ester-based resin, olefin-based resin, polyethylene-based resin, ionomer, etc. as a base material. may include In particular, since the first sealing material 131 and the second sealing material 132 are made of ethylene vinyl acetate, it is possible to have excellent properties even at a low material cost. However, the present invention is not limited thereto. Accordingly, the sealing material 130 may include various materials other than those described above and may have various shapes.

Here, the first sealing material 131 and the second sealing material 132 may include different materials. For example, one of the first and second sealing materials 131 and 132 may entirely include a part or a different material from the other, and at least a portion of one of the first and second sealing materials 131 and 132 may It may also contain a material different from the other part or all. Various other modifications are possible.

In the present embodiment, as described above, the sealing material 130 may have a central area CA and an outer area EA. Hereinafter, an example of the solar cell 10 that may be included in the solar cell panel 100 according to the embodiment of the present invention will be first described with reference to FIGS. 3 and 4 , and then the sealing material 130 as described above will be described in detail. Explain.

3 is a cross-sectional view illustrating an example of a solar cell 10 that may be included in the solar cell panel 100 shown in FIG. 1 , and FIG. 4 is a schematic plan view of the solar cell 10 shown in FIG. 3 . . FIG. 3 is a cross-sectional view taken along line III-III of FIG. 1 .

3 and 4 , the solar cell 10 includes a semiconductor substrate 12 including a base region 14 and a conductive region ( 20 and 30 , and electrodes 42 and 44 connected to the conductive regions 20 and 30 . The semiconductor substrate 12 , the conductive regions 20 , 30 , etc. may constitute a photoelectric conversion unit involved in photoelectric conversion. Here, the conductivity-type regions 20 and 30 may include a first conductivity-type region 20 and a second conductivity-type region 30 having different conductivity types, and the electrodes 42 and 44 have a first conductivity type. It may include a first electrode 42 connected to the mold region 20 and a second electrode 44 connected to the second conductivity-type region 30 . This will be described in more detail.

The semiconductor substrate 12 may include a base region 14 having the first or second conductivity type by including the dopant of the first or second conductivity type at a relatively low doping concentration. In addition, a first conductivity type region 20 having a first conductivity type may be formed on one surface (eg, a front surface) of the semiconductor substrate 12 . In addition, a second conductivity type region 30 having a second conductivity type may be formed on the other surface (eg, a rear surface) side of the semiconductor substrate 12 . In this case, the first and second conductivity-type regions 20 and 30 have a different conductivity type from the base region 14 , or have the same conductivity type as the base region 14 and have a higher doping concentration than the base region 14 . have

In the present embodiment, various materials capable of representing n-type or p-type may be used as the first or second conductivity-type dopant. As the p-type dopant, boron (B), aluminum (Al), gallium (Ga), indium (In), etc. can be used, and in the case of the n-type dopant, phosphorus (P), arsenic (As), bismuth (Bi), antimony Group 5 elements, such as (Sb), can be used. For example, the p-type dopant may be boron (B) and the n-type dopant may be phosphorus (P).

Among the first and second conductivity type regions 20 and 30 , one region having a conductivity type different from that of the base region 14 constitutes at least a portion of the emitter region. The emitter region forms a pn junction with the base region 14 to generate carriers by photoelectric conversion. Another one 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 portion of a surface field region. The electric field region forms an electric field that prevents loss of carriers by recombination at the surface of the semiconductor substrate 12 . For example, in this embodiment, the base region 14 has a second conductivity type, the first conductivity type region 20 constitutes an emitter region, and the second conductivity type region 30 constitutes a rear electric field region. can do. However, the present invention is not limited thereto.

The semiconductor substrate 12, or the base region 14 formed thereon, and the first and second conductivity-type regions 20 and 30 are a single crystalline semiconductor containing a dopant (e.g., a single single crystal or a polycrystalline semiconductor, for example, monocrystalline or polycrystalline silicon, in particular monocrystalline silicon). As described above, the solar cell 10 based on the base region 14 or the semiconductor substrate 12 having few defects due to its high crystallinity has excellent electrical characteristics. In addition, an anti-reflection structure capable of minimizing reflection (eg, a texturing structure having a pyramid shape) may be formed on the front surface and/or the rear surface of the semiconductor substrate 12 .

In this embodiment, the first and second conductivity-type regions 20 and 30 may be configured as doped regions constituting a part of the semiconductor substrate 12 . As another example, at least one of the first and second conductivity-type regions 20 and 30 may be formed on the semiconductor substrate 12 separately from the semiconductor substrate 12 . In this case, the first or second conductivity type regions 20 and 30 may be composed of an amorphous semiconductor layer, a microcrystalline semiconductor layer, or a polycrystalline semiconductor layer (eg, an amorphous silicon layer, a microcrystalline silicon layer, or a polycrystalline silicon layer). can In this case, a separate layer (a tunneling layer, a passivation layer, etc.) may be formed between the first or second conductivity-type regions 20 and 30 and the semiconductor substrate 12 .

and a first passivation film 22 and/or reflection as a first insulating film on at least the front surface of the semiconductor substrate 12 (more precisely, on the first conductivity type region 20 formed on the front surface of the semiconductor substrate 12 ) A barrier film 24 may be positioned. In addition, a second passivation film 32, which is a second insulating film, may be positioned at least on the rear surface of the semiconductor substrate 12 (more precisely, on the second conductivity-type region 30 formed on the rear surface of the semiconductor substrate 12). there is.

The first passivation layer 22 , the antireflection layer 24 , and the second passivation layer 32 may be formed substantially entirely on the semiconductor substrate 12 , except for the openings 102 and 104 . For example, the first passivation film 22 , the antireflection film 24 , or the second passivation film 32 is a silicon nitride film, a silicon nitride film containing hydrogen, a silicon oxide film, a silicon oxynitride film, an aluminum oxide film, a silicon carbide film, MgF ₂ , ZnS, TiO ₂ and CeO ₂ Any single layer selected from the group consisting of or a combination of two or more layers may have a multilayer structure. For example, the first passivation layer 22 and/or the anti-reflection layer 24 , and the second passivation layer 32 may not include a dopant or the like to have excellent insulating properties and passivation properties. However, the present invention is not limited thereto.

The first electrode 42 is formed while filling at least a portion of the first opening 102 to be electrically connected to (eg, contacted) the first conductivity-type region 20 , and the second electrode 44 is formed to 2 It is formed while filling at least a portion of the opening 104 and is electrically connected to the second conductivity-type region 30 (eg, a contact is formed). The first and second electrodes 42 and 44 are made of various conductive materials (eg, metal) and may have various shapes.

For example, at least one of silver (Ag), aluminum (Al), gold (Au), titanium (Ti), tungsten (W), and copper (Cu) using the first and second electrodes 42 and 44 as a conductive material. may contain one. In this case, the first and second electrodes 42 and 44 may be formed by various methods. For example, at least one of the first and second electrodes 42 and 44 may be manufactured by printing, plating, sputtering, or the like. The first and second electrodes 42 and 44 may be formed by various other methods. The first electrode 42 may include a plurality of finger electrodes 42a spaced apart from each other while having a constant pitch and formed in one direction. Although the figure illustrates that the finger electrodes 42a are parallel to each other and parallel to the edge of the semiconductor substrate 12, the present invention is not limited thereto. In addition, the first electrode 42 may include a bus bar electrode 42b formed in a direction crossing (eg, orthogonal) to the finger electrodes 42a and connecting the finger electrodes 42a. An interconnector 142 may be attached to the bus bar electrode 42b. Only one bus bar electrode 42b may be provided, or a plurality of bus bar electrodes 42b may be provided while having a pitch larger than that of the finger electrodes 42a, as shown in FIG. 4 . In this case, the width of the bus bar electrode 42b may be greater than the width of the finger electrode 42a, but the present invention is not limited thereto. Accordingly, the width of the bus bar electrode 42b may be equal to or smaller than the width of the finger electrode 42a.

The second electrode 44 may include a finger electrode and a bus bar electrode respectively corresponding to the finger electrode 42a and the bus bar electrode 42b of the first electrode 42 . As for the finger electrode and the bus bar electrode of the second electrode 44 , the contents of the finger electrode 42a and the bus bar electrode 42b of the first electrode 42 may be applied as they are. The width and pitch of the finger electrodes 42a of the first electrode 42 may be the same as or different from the width and pitch of the finger electrodes of the second electrode 44 . The width of the bus bar electrode 42b of the first electrode 42 may be the same as or different from the width of the bus bar electrode of the second electrode 44 , but the width of the bus bar electrode 42b of the first electrode 42 may be different. ) and the bus bar electrode of the second electrode 44 may be disposed to have the same pitch at the same location.

As described above, in the present embodiment, the first and second electrodes 42 and 44 are partially formed while having a constant pattern. Accordingly, light may be incident to a portion where the first and second electrodes 42 and 44 are not formed. The solar cell 10 has a double-sided light-receiving type (bi-facial) structure in which light can be incident to the front and rear surfaces of the semiconductor substrate 12 . However, the present invention is not limited to the specific shapes of the first and second electrodes 42 and 44 and may have various shapes. In addition, although the double-sided light-receiving structure is illustrated in the drawings, various modifications are possible, such as the second electrode 44 being formed entirely on the rear surface of the semiconductor substrate 12 .

Hereinafter, the sealing material 130 and the first and second cover members 110 and 120 of the solar cell panel 100 according to an embodiment of the present invention will be described in detail with reference to FIGS. 5 to 7 .

5 is a schematic plan view illustrating a solar cell panel 100 according to an embodiment of the present invention, and FIG. 6 is a cross-sectional view taken along line VI-VI of FIG. 5 . For clear understanding and simplified illustration, in FIG. 5 , the central area CA and the outer area EA of the solar cell 10 and the sealing material 130 are mainly illustrated.

5 and 6 , in the present embodiment, the sealing material 130 is located outside the central region CA and the central region CA, and the reinforcement region EA1 has a greater thickness than the central region CA. It may include an outer area EA provided with this. Accordingly, the solar cell panel 100 may include an outer portion positioned outside the central portion and provided with a reinforcing portion having a thickness greater than that of the central portion. Here, the thickness of the sealing material 130 is the distance between the first cover member 110 and the second cover member 120 (ie, the inner surface of the first cover member 110 and the inner surface of the second cover member 120 ). distance between the sides). In addition, the thickness of the solar cell panel 100 may be defined as a distance between the outer surface of the first cover member 110 and the outer surface of the second cover member 120 .

The central region CA is a region that includes and is connected to the center of the solar panel 100 , and has substantially the same thickness as the first thickness T1 of the encapsulant 130 at the center of the solar panel 100 . It may mean an area with For example, the thickness of the central region CA may have a difference of less than 30 μm or less than 10% from the first thickness T1 of the sealing material 130 in the central portion of the solar cell panel 100 . Such a difference is a difference in a degree that may be caused by a thickness difference due to the sealing material 130 itself, errors in equipment measuring the thickness of the sealing material 130 , and the like. The central area CA may be positioned to include a portion in which the inner solar cell 10b other than the outer solar cell 10a positioned adjacent to the outer side of the solar cell panel 100 is located among the plurality of solar cells 10 . can In this specification, the outer solar cell 10a may mean an outermost solar cell closest to the edge of the solar panel 100 . And, the outer area EA is an area including at least a part of the edge of the solar cell panel 100 . In this embodiment, the outer area EA has a thickness greater than the first thickness T1 of the central area CA. The branch includes a reinforcement area EA1. The reinforcement area EA1 or the outer area EA may be positioned near the outer side of the solar cell panel 100 while overlapping at least a portion of the outer solar cell 10a.

As such, when the encapsulant 130 is formed to have the reinforcing area EA1 having a relatively thick thickness in the vicinity of the outside, the encapsulant 130 in the lamination process (refer to FIG. ) can be minimized or prevented from reducing the thickness of the sealing material 130 in the vicinity of the edge of the solar cell panel 100 due to external leakage. Accordingly, the sealing material 130 at the edge of the solar cell panel 100 may have a thickness capable of maintaining a minimum sealing characteristic. In addition, it is possible to prevent damage to the solar cell 10 and the first or second cover members 110 and 120 that may occur near the edge or corner of the solar cell panel 100 . In particular, in the solar cell panel 100 in which the first cover member 110 and the second cover member 120 each include a glass substrate, pressure is concentrated on the edge or corner of the solar cell panel 100 during the lamination process. Therefore, it is possible to effectively prevent a problem in which the sealing property is greatly reduced in the corresponding portion or the glass substrate constituting the first or second cover members 110 and 120 is broken.

On the other hand, in the related art, pressure is concentrated on the edge or corner portion of the solar cell panel 100 during the lamination process, so that the sealing property is greatly reduced at the edge or corner portion of the solar cell panel 100, or the solar cell 10, the first or The second cover members 110 and 120 may be damaged. This problem may be more serious when the first cover member 110 and the second cover member 120 each include a glass substrate.

Here, even if a partial region (eg, an edge or corner region) of the sealing material 130 is thickened before the lamination process, the sealing material in the edge or corner region during or after the lamination process due to heat and pressure applied in the lamination process. The thickness of 130 may be the same as or reduced to other portions. Accordingly, even if a portion of the sealing material 130 is thickened, if the solar cell panel 100 does not include the reinforcement area EA1 after the lamination process, the sealing material 130 generated near the edge or corner of the solar cell panel 100 . ), there is a difficulty in preventing the outflow or buffering the pressure applied to the first or second cover member (110, 120). Accordingly, in the present embodiment, the reinforcing area EA1 having a relatively thick thickness is left on the outside of the sealing material 130 even after the lamination process, so that the sealing material 130 is leaked near the edge or corner of the solar cell panel 100 . However, the sealing material 130 at the edge of the solar cell panel 100 has a thickness of a certain level or more, so that the sealing characteristics can be improved. In addition, the region having a thick thickness in the lamination process may act as a kind of buffering action due to the remaining of the reinforcement region EA1. Accordingly, it is possible to effectively prevent the glass substrate constituting the first or second cover members 110 and 120 from being broken in the lamination process.

On the other hand, when an auxiliary sealing film or the like is further provided with a thickness for removing air bubbles, it is difficult to solve the problem that the thickness of the sealing material is thinner than the desired thickness at the edge portion due to the outflow of the sealing material at the edge portion.

For example, in the present embodiment, the outer area EA has an edge having a thickness smaller than that of the reinforcing area EA1 and the second thickness T2 that is located outside the reinforcing area EA1 and is the maximum thickness of the reinforcing area EA1. The positioned edge area EA2 may be included. Here, the reinforcement area EA1 may be positioned to overlap at least a portion of the outer solar cell 10a. In this case, the reinforcing area EA1 may include a portion in which the thickness of the encapsulant 130 is gradually increased toward the edge of the outer solar cell 10a adjacent to the edge of the solar cell panel 100 . In addition, the thickness of the sealing material 130 may gradually decrease in the edge area EA2 toward the edge of the solar cell panel 100 . For example, the reinforcing area EA1 may be defined as a portion where the thickness of the sealing material 130 gradually increases from the first thickness T1 to reach the second thickness T2 that is the maximum thickness, and the edge area EA2 ) is a portion in which the reinforcement area EA1 gradually decreases from the second thickness T2, which is the maximum thickness of the sealing material 130, to the third thickness T3, which is the thickness at the edge of the solar panel 100. can be defined.

In this embodiment, the thickness of the solar cell panel 100 is uniform (for example, with an error of within 10%, for example, within 5%) of the first and second cover members 110 and 120 as a whole. has a shape substantially the same as or similar to the thickness of the sealing material 130 . Accordingly, the solar cell panel 100 may include a central portion having substantially the same thickness and an outer portion positioned outside the central portion and provided with a reinforcing portion having a thickness greater than that of the central portion. In this case, the outer portion of the solar cell panel 100 may further include an edge portion having an edge having a thickness smaller than the maximum thickness of the reinforcement portion. Here, the reinforcing portion may include a portion in which the thickness of the solar cell panel 100 is gradually increased while facing outward from the central portion. In addition, the thickness of the solar cell panel 100 may gradually decrease as the edge portion moves toward the edge of the solar cell panel 100 . For example, the thickness of the solar cell panel 100 gradually increases from the reinforcement portion toward the edge of the outer solar cell 10a to reach the maximum thickness, and then toward the edge of the solar cell panel 100 from the edge portion. may decrease gradually.

Here, the second thickness T2 of the reinforcing area EA1 may be 30 μm or more (more specifically, 30 μm to 500 μm) greater than the first thickness T1 of the central area CA. For example, the second thickness T2 of the reinforcing area EA1 may be greater than or equal to 60um (more specifically, 60um to 300um) than the first thickness T1 of the central area CA. Alternatively, a ratio of a difference between the second thickness T2 of the reinforcement area EA1 and the first thickness T1 of the central area CA to the first thickness T1 of the central area CA is 10% or more (one For example, 10% to 35%) may be used. Only by having such a thickness difference can the effect of the reinforcing area EA1 be sufficiently realized while material cost can be reduced. When the difference between the first thickness T1 and the second thickness T2 is too large (eg, exceeds 500 μm), the structural stability of the solar cell panel 100 may be deteriorated. However, the present invention is not limited thereto, and the thickness of the reinforcing area EA1 may be variously modified.

In this embodiment, for example, the third thickness T3 , which is the thickness of the sealing material 130 at the edge of the solar cell panel 100 , is smaller than the second thickness T2 , and is equal to or equal to the first thickness T1 . It can be smaller than this. In particular, the third thickness T3 of the sealing material 130 may be smaller than the first thickness T1 . This is because, even when the reinforcement area EA1 is provided, the third thickness T3 of the sealing material 130 may be reduced due to the outflow of the sealing material 130 near the edge. In order to prevent this, if the lamination equipment is changed as a whole or an additional member is used, the manufacturing process becomes complicated and productivity may decrease. In the present embodiment, even in the above-described case, the ratio of the third thickness T3 to the first thickness T1 may be 80% or more (eg, 90% or more). This is because the reinforcing area EA1 prevents the third thickness T3 from being too small compared to the first thickness T1 .

The width of the edge area EA2 may be greater than the width of the reinforcement area EA1 when viewed in a direction from the center to the edge of the solar cell panel 100 . Accordingly, the thickness of the sealing material 130 in the edge area EA2 is gently reduced, so that structural stability can be improved. However, the present invention is not limited thereto, and the width of the reinforcement area EA1 may be equal to or greater than the width of the edge area EA2 . When viewed from the center of the solar panel 100 toward the edge, the degree to which the thickness increases in the reinforcement area EA1 (ie, the absolute value of the inclination) is the degree to which the thickness decreases in the edge area EA2 (ie, the absolute value of the inclination). , the absolute value of the slope) may be equal to, greater than, or less than. For example, the degree to which the thickness is increased in the reinforcement area EA1 (ie, the absolute value of the slope) may be greater than the degree to which the thickness is decreased in the edge area EA2 (ie, the absolute value of the slope). Accordingly, the thickness of the sealing material 130 in the edge area EA2 is gently reduced, so that structural stability can be improved. However, the present invention is not limited thereto and may be variously modified.

For example, a portion of the sealing material 130 having a second thickness T2 that is the maximum thickness may be located adjacent to an outer boundary portion of the outer solar cell 10a. That is, the portion of the sealing material 130 having the second thickness T2, which is the maximum thickness, is located within 20% of the length (eg, the maximum length) of the outer solar cell 10a at the outer boundary of the outer solar cell 10a. can do. However, the present invention is not limited thereto. Accordingly, the position of the portion of the sealing material 130 having the second thickness T2, which is the maximum thickness, coincides with the outer boundary of the outer solar cell 10a, is located inside the outer boundary of the outer solar cell 10a, or It may be located outside the outer boundary of the outer solar cell 10a. Various other modifications are possible.

In FIG. 6 , the boundaries of the central part, the reinforcement part, and the edge part of the solar cell panel 100 coincide with the boundaries of the central area CA, the reinforcement area EA1, and the edge area EA2 of the sealing material 130, respectively. It is exemplified to be located in . However, the present invention is not limited thereto. Therefore, the difference in thickness of the sealing material 130 is not reflected in the first and second cover members 110 and 120 as it is, so that the boundaries of the central portion, the reinforcing portion, or the edge portion of the solar cell panel 100 are in the central region of the sealing material 130 , respectively. (CA), the reinforcement area (EA1), or the edge area (EA2) does not perfectly coincide with the boundaries of the area may have a slight difference.

In the present exemplary embodiment, the central area CA may have a larger area than each of the outer area EA, the reinforcement area EA1, and the edge area EA2. That is, the outer area EA may have an area ratio of less than 50% with respect to the total area of the solar cell panel 100 or the encapsulant 130 . More specifically, the outer area EA or the reinforcing area EA1 may be positioned to overlap at least a portion of the outer solar cell 10a but not overlap the inner solar cell 10b. Accordingly, the material cost of the sealing material 130 may be reduced by reducing the area of the outer area EA or the reinforcing area EA1 . However, the present invention is not limited thereto.

For example, as shown in FIG. 5 , the solar cell string S is elongated in the first direction (y-axis direction of the drawing), and the outer area EA (or the reinforcement area EA1 included therein), below The outer areas EA may be respectively located on both sides of the second direction (x-axis direction in the drawing) intersecting the first direction to have a shape extending in the first direction. Since bus ribbons (reference numeral 145 in FIG. 1, hereinafter the same) are located at both ends (ie, both ends in the first direction) of the solar cell string S, even when pressure is applied during the lamination process, the first or second cover While the phenomenon such as damage or cracking of the members 110 and 120 (solar cells), etc. is less serious, the bus ribbon 145 and the like are not located on both sides in the second direction, so the A phenomenon such as damage or breakage of the first or second cover members 110 and 120 and the solar cell 10 may easily occur. In consideration of this, in the present embodiment, the first or second cover members 110 and 120, the solar cell 10, and the like are damaged or broken by pressure so that the outer areas EA are respectively located on both sides in the second direction. phenomenon can be effectively prevented. At this time, since the outer area EA has a shape extending in a direction parallel to the solar cell string S or in a long axis direction, a small number of reinforcing parts 132b may have a sufficient area and effectively reinforce a portion where pressure is concentrated. can do. In addition, since the outer area EA is not located in the direction crossing the solar cell string S or the short axis direction, material cost can be reduced. In this case, when viewed from the second direction, the thickness of the sealing material 130 or the solar cell panel 100 is greater than the central area CA or the central area, the outer area EA or at least a portion of the outer portion (eg, the reinforcing area EA1 ). ) or reinforcement) may be larger. Contrary to this, if the reinforcement parts are located at both ends in the longitudinal direction of the solar cell panel 100, it may be difficult to solve the problem of reducing the thickness of the sealing material 130 that may occur along the longitudinal direction of the solar cell panel 100. .

However, the present invention is not limited thereto, and the outer area EA may be positioned at least partially at an edge or a corner portion of the solar cell panel 100 . As a modification, for example, as shown in (a) of FIG. 7 , the outer area EA may have a shape extending long in a direction crossing the solar cell string S or a short axis direction. In this case, when viewed from the first direction, the thickness of the sealing material 130 or the solar cell panel 100 may be greater in the central area CA or at least a portion of the outer area EA or the outer portion than the central area CA. Then, the area of the outer area EA may be reduced, thereby reducing material cost. As another example, as shown in (b) of FIG. 7 , the outer area EA has a frame shape continuously extending along the entire edge of the solar cell panel 100 to maximize the effect of the outer area EA can do. In this case, when viewed from each of the first and second directions, the thickness of the sealing material 130 or the solar cell panel 100 may be greater in the central area CA or at least a portion of the outer area EA or the outer portion than the central area CA. . As another example, as shown in FIG. 7C , the outer area EA may be partially positioned to correspond to each of the four corners of the solar cell panel 100 . Accordingly, the area of the outer area EA may be minimized. In this case, the thickness of the encapsulant 130 or the solar cell panel 100 may be greater in the outer area EA or at least a portion of the outer portion than the central area CA or the central portion when viewed from one direction near the edge. As another example, as shown in (d) of FIG. 7 , a plurality of outer areas EA may be located in a direction parallel to the solar cell string S or in a long axis direction. The outer area EA may have various other planar shapes.

The difference in thickness between the central area CA and the outer area EA (in particular, the reinforcing area EA1) of the sealing material 130 is that at least one of the first and second sealing materials 131 and 132 is made of a reinforcing sealing material. It may be due to being Here, the reinforcing sealant refers to a reinforcement having a base portion (reference numeral 132a in FIG. 8A , hereinafter the same) and an overlapping portion OP positioned on the base portion 132a and overlapping a part of the solar cell 10 . It may refer to a sealing material having a portion (reference numeral 132b in FIG. 8A, hereinafter the same). The reinforcing sealant will be described in more detail later with reference to FIGS. 8A to 8C, and FIGS. 10 and 11 . If the reinforcing sealant includes the reinforcing portion 132b, a portion having a relatively larger thickness than other portions remains even when pressed by pressure during the lamination process, so the reinforcing region ( EA1) may be located. Here, the position of the reinforcing area EA1 to correspond to the reinforcing portion 132b means that the reinforcing portion 132b and the reinforcing area EA1 completely coincide with each other as well as the portion where the reinforcing portion 132b is present. It may mean that the reinforcement area EA1 is positioned to overlap at least a part. For example, the reinforcing area EA1 may have the same or similar shape as the reinforcing portion 132b in an area smaller than the reinforcing portion 132b, or may have a shape and/or area different from that of the reinforcing portion 132b. Alternatively, the reinforcing area EA1 may have the same or similar shape and/or area as the reinforcing portion 132b in an area equal to or larger than the reinforcing portion 132b, and may have a different shape and/or area than the reinforcing portion 132b. may have In this case, at least a portion of the reinforcing portion 132b moves inward to extend the reinforcing area EA1 inward, and the edge area EA2 may be located outside the reinforcing area EA1.

For example, in the method of manufacturing the solar cell panel 100, the second sealing material 132 to be positioned on the upper side or on the side to which pressure is applied during the lamination process (refer to FIG. 8A, hereinafter the same) or the lamination process is a reinforcing sealing material. can Having such a structure may maximize the buffering effect of the reinforcing portion 132b or the reinforcing area EA1 during the lamination process. However, the present invention is not limited thereto. Accordingly, the first sealing material 131 may be formed of a reinforcing sealing material, or the first and second sealing materials 131 and 132 may be formed of a reinforcing sealing material, respectively. In addition, the reinforcing portion 132b is disposed on a surface opposite to the first or second cover member 110 or 120 in the first or second sealing member 131 or 132 , or an opposite side thereof, or the first or second sealing member. It may be located on both sides of (131, 132). Various other modifications are possible.

Due to the shape of the sealing material 130 described above, the first and/or second cover members 110 and 120 may have a shape including a partially curved, rounded, or inclined portion. For example, the portion having the second thickness T2 in the outer area EA (or the outer portion) may have a shape of a protrusion protruding toward the outside. For example, the reinforcement area EA1 (or the reinforcement part) and the edge area EA2 (or the edge part) may have shapes corresponding to at least a part of a kind of Gaussian distribution. In this case, the outer area EA has a shape of a protrusion protruding toward the outside in the portion having the second thickness T2 and has inflection points on both sides of the portion having the second thickness T2 and is concavely formed. It may have a negative shape. However, the present invention is not limited thereto, and the outer area EA may have a shape of a protrusion protruding toward the outside as a whole.

As an example, in FIG. 6 , even when the second sealing material 132 is formed of a reinforcing sealing material, the first and second cover members 110 and 120 have symmetrical shapes. This is because the pressure is maintained below a certain level in the lamination process or pressure is applied with air or the like, thereby improving structural stability. However, the present invention is not limited thereto. When the reinforcing portion 132b is provided on any one of the first and second sealing materials 131 and 132, the first or second cover members 110 and 120 adjacent thereto include a partially curved, rounded, or inclined portion. and the first or second cover members 110 and 120 that are not adjacent thereto may have a flat plate shape. In addition, various modifications are possible.

In this case, in the reinforcing sealant, the reinforcing portion 132b may be made of the same material as the base portion 132a. In this case, the first or second sealing materials 131 and 132 or the sealing material 130 may be made of the same material without boundaries to constitute an integral structure and a single body. Then, the outer area EA or the reinforcing area EA1 may have the same material as the central area CA when viewed with respect to one surface (front or rear) of the solar cell 10 .

Alternatively, in the reinforcing sealant, the reinforcing portion 132b may have a material different from that of the base portion 132a. Then, when viewed with respect to one surface (front or rear) of the solar cell 10 , at least a portion of the outer area EA or the reinforcing area EA1 may include a portion having a material different from that of the central area CA. . For example, a portion having a material different from that of the central area CA in the outer area EA or the reinforcing area EA1 may be formed of a material having a lower hardness and higher elasticity than the other portions. Then, the cushioning action may be maximized by the low hardness and high elasticity in the reinforcing area EA1 . However, the present invention is not limited thereto. Accordingly, materials of the base portion 132a and the reinforcing portion 132b may be variously modified. As described above, when the second sealing material 132 includes the reinforcing portion 132b, at least a portion of the portion made of another material in the sealing material 132 is disposed between the solar cell 10 and the second cover member 120 . It may be located on the outside. However, the present invention is not limited thereto.

Here, when any one of the first and second sealing materials 131 and 132 is formed of a reinforcing sealant, the base portion 132a and the reinforcing portion 132b of the reinforcing sealing material are formed of the first and second sealing materials 131 and 132 ) may have the same material or a different material as some or all of the other.

Hereinafter, the base portion 132a and the reinforcing portion 132b of the encapsulant 130, and the first area A1 and the second area of the encapsulant 130, while describing the manufacturing method of the solar cell panel 100 in detail ( A2) will be described in detail.

8A to 8C are diagrams schematically illustrating a method of manufacturing a solar cell panel 100 according to an embodiment of the present invention. 9 illustrates a sealing material 130 (eg, a second sealing material 132) having a base portion 132a and a reinforcing portion 132b applicable to the solar cell panel 100 according to an embodiment of the present invention. It is a schematic plan view showing the solar cell 10 together.

First, as shown in FIG. 8A , in the lamination process, the first cover member 110 , the first sealing material 131 , the solar cell 10 and the first sealing material 132 on the work table 200 of the lamination apparatus, and The stacked structure 100a in which the second cover member 120 is stacked is positioned. 8A and 8B show the first cover member 110, the first sealing material 131, the solar cell 10, and the first sealing material 132 and the second cover member 120 spaced apart from each other for clear understanding. However, in reality, they may be positioned in contact with each other.

At this time, at least one of the first and second sealing materials 131 and 132, for example, in this embodiment, the second sealing material 132, is located on the base portion 132a and the base portion 132a, and the solar cell ( 10) and a reinforcing portion 132b having an overlapping portion OP overlapping at least a portion of the 10).

When the reinforcing portion 132b is disposed to have the overlapping portion OP overlapping with at least a portion of the solar cell 10 as described above, the effect of the reinforcing portion 132b may be effectively implemented. As an example, the reinforcing portion 132b may include an overlapping portion OP adjacent to the edge of the solar cell panel 100 and overlapping at least the outer solar cell 10a. A ratio of the width of the overlapping portion OP to the width of the outer solar cell 10a may be 10% or more. Alternatively, the width W of the reinforcing portion 132b may be 5 cm or more (eg, 7 cm or more). Within this range, the effect of the reinforcing portion 132b may be maximized. In this case, the overlapping portion OP may be positioned so as not to overlap the inner solar cell 10b.

In addition, the first region A1 provided with only the base portion 132a without the reinforcing portion 132b may have a larger area than the second area A2 provided with the base portion 132a and the reinforcing portion 132b together. . That is, the reinforcing portion 132b may have an area ratio of less than 50% with respect to the total area of the sealing material 130 . Accordingly, it is possible to reduce the material cost of the sealing material 130 by reducing the area of the reinforcing portion 132b. However, the present invention is not limited thereto.

In this case, the base portion 132a has a constant thickness T10 and the reinforcing portion 132b has a constant thickness T20 . Accordingly, the first region A1 provided with only the base portion 132a without the reinforcing portion 132b has only the thickness T10 of the base portion 132a, and the base portion 132a and the reinforcing portion 132b are provided together. The formed second region A2 may have a thickness corresponding to the sum of the thickness T10 of the base portion 132a and the thickness T20 of the reinforcing portion 132b. For example, the first region A1 may have a thickness of 100 to 600 μm, and the second region A2 may have a thickness of 150 to 1100 μm. Accordingly, the second region A2 in which the reinforcing portion 132b is provided may have a relatively large thickness. As such, the reinforcing portion 132b is partially formed in a portion where pressure is concentrated during the lamination process to damage the first and second cover members 110 and 120 and/or the solar cell 10 to increase the thickness. It is a part that acts as a buffering or reinforcing part. In addition, since the first region A1 has a relatively thin thickness, the material cost may be reduced by reducing the volume or thickness of the sealing material 130 in the first region A1 .

In particular, in the present embodiment, a reinforcing sealing material that allows the reinforcing area EA1 formed in a portion corresponding to at least a portion of the reinforcing portion 132b to have a relatively larger thickness than the central area CA may be used even after the lamination process. . Then, the sealing material 130 can be prevented from leaking to the outside by the reinforcing portion 132b of the reinforcing sealing material, and the first and second cover members 110 and 120 and/or the first and second cover members 110 and 120 during the lamination process by maximizing the buffer action. It is possible to effectively prevent damage or breakage of the solar cell 10 .

For example, the thickness T20 of the reinforcing portion 132b may be smaller than the thickness T1 of the base portion 132a. On the other hand, if the thickness T2 of the reinforcing portion 132b is large, the step difference between the first area A1 and the second area A2 may increase, and thus undesirable process defects may occur. For example, the ratio (T20/T10) of the thickness T20 of the base portion 132a to the thickness T10 of the reinforcement portion 132b may be 0.3 to 0.8. However, the present invention is not limited thereto.

The reinforcing part 132b may have a shape corresponding to the outer area EA shown in FIGS. 5 and 7 .

For example, to correspond to the outer area EA shown in FIG. 5 , as shown in FIG. 9 , the reinforcing portion 132b is formed in a first direction (y-axis direction in the drawing) in which the solar cell string S extends. ), the reinforcing parts 132b may be respectively located on both sides of the second direction (x-axis direction in the drawing) intersecting the first direction. If the reinforcing sealant including the reinforcing portion 132b is used, the outer area EA as shown in FIG. 5 may be formed.

And as a modification, the reinforcing portion 132b intersects the solar cell string S to correspond to the outer area EA (or the reinforcing area EA1, hereinafter the same) shown in FIG. 7A . It may have a shape extending long in a direction or a minor axis direction. As another example, to correspond to the outer area EA shown in FIG. 7B , the reinforcing portion 132b may have a frame shape continuously extending along the entire edge of the solar cell panel 100 . As another example, in order to correspond to the outer area EA shown in FIG. 7C , the reinforcing portion 132b is partially positioned to correspond to each of the four corners of the base portion 132a or the solar cell panel 100 . can do. Accordingly, the area of the reinforcing portion 132b may be minimized. As another example, a plurality of reinforcing parts 132b may be positioned in a direction parallel to or along a major axis of the solar cell string S to correspond to the outer area EA shown in FIG. 7D . The reinforcing portion 132b may have various other planar shapes.

Subsequently, as shown in FIG. 8B , in the lamination process, heat and pressure are applied to the laminate structure 100a to apply the first cover member 110 , the first sealing material 131 , the solar cell 10 , and the first sealing material 132 . And the second cover member 120 is integrated. That is, the sealing material 130 completely fills the space between the first cover member 110 and the second cover member 120 that is melted and hardened at a high temperature in the lamination process and compressed by pressure. The battery 10 may be sealed. Accordingly, the space between the first cover member 110 and the second cover member 120 may be completely filled by the sealing material 130 . Accordingly, the solar cell panel 100 as shown in FIG. 8C is manufactured. For example, the first cover member 110 , the first sealing material 131 , the solar cell 10 , and the first sealing material 132 and the second cover member 120 may be integrated by providing air pressure. Accordingly, the lamination process may be performed without applying a large pressure to the solar cell 10 or the like.

If the first and second cover members 110 and 120 are not used in the manufacturing of the solar cell panel 100 including the glass substrate, the reinforcing sealant having the reinforcing portion 132b is not used during the lamination process. Damage or breakage of the cover members 110 and 120 and/or the solar cell 10 may be severe, and in this embodiment, a reinforcing sealant having the reinforcing portion 132b may be used to effectively prevent this. .

As described above, in the present embodiment, even after the lamination process, the sealing material 130 may include a central area CA and an outer area EA (eg, the reinforcing area EA1) having different thicknesses, and thus Correspondingly, a portion (reinforcing portion) having a greater thickness than the central portion in the outer portion of the solar cell panel 100 may be provided. In this structure, it effectively prevents a reduction in the thickness of the sealing material 130 that may occur at the edge of the solar cell panel 100 due to the outflow of the sealing material 130 to the outside, and the first and second cover members 110 and 120 and / Alternatively, damage or breakage of the solar cell 10 may be more effectively prevented. Thereby, the defect rate at the time of manufacturing the solar cell panel 100 can be reduced.

8A to 8C, the base portion 132a and the reinforcing portion 132b are made of the same material as each other and constitute an integral structure, so that the reinforcing sealant including the reinforcing portion 132b has a single body. . Such a reinforcing sealant may be formed by extrusion. For example, it may be formed by extrusion processing using a T-die, calendering, or the like.

However, the present invention is not limited thereto. As a modification, as shown in FIG. 10 , the base portion 132a and the reinforcing portion 132b may have different materials or may be formed separately. The base portion 132a and the reinforcing portion 132b are attached and used by an adhesive layer (not shown), or the reinforcing portion 132b is placed on the base portion 132a without a separate adhesive layer to form the laminate structure 100a. It may also be used by forming a part. When the base portion 132a and the reinforcing portion 132b include different materials, the reinforcing portion 132b may be formed of a material capable of maximizing a buffering action. For example, the reinforcing portion 132b may have lower hardness and higher elasticity than the base portion 132a to maximize the cushioning action. However, the present invention is not limited thereto, and the base portion 132a and the reinforcing portion 132b may include various materials.

A photo of a solar cell panel provided with a reinforcing sealing material having a reinforcing portion 132b as in the embodiment of the present invention is attached to FIG. A photograph of a solar cell panel according to a comparative example having a sealing material without a was attached. The solar cell panels according to Examples and Comparative Examples had all the same structures, materials, properties, etc. except for whether or not the encapsulant had a reinforcing part. As shown in FIG. 11( a ), in the solar cell panel according to the embodiment of the present invention, cracking of the solar cell did not occur, but as shown in FIG. 11( b ), in the solar cell panel according to the comparative example, the solar cell It can be seen that the battery is broken. From this, it can be seen that the cracking of the solar cell in the lamination process can be prevented by the first and/or second sealing materials 131 and 132 including the reinforcing part 132b.

In addition, since the lamination process can be performed at a high temperature and/or a sufficient pressure by the reinforcing part 132b, the process time of the lamination process can be effectively shortened. For example, the process time of the lamination process can be reduced by 20%. On the other hand, in the portion of the first and/or second sealing materials 131 and 132 to which a relatively small pressure is applied during the lamination process, only the base portion 132a having a relatively small thickness is positioned to reduce the material cost of the sealing material 130 . can be minimized Accordingly, the productivity at the time of manufacturing the solar cell panel 100 can be greatly improved.

Hereinafter, solar panels according to other embodiments of the present invention will be described in detail. A detailed description of the same or extremely similar parts to the above description will be omitted and only different parts will be described in detail. In addition, combinations of the above-described embodiment or a modified example thereof and the following embodiment or a modified example thereof are also within the scope of the present invention.

12 is a cross-sectional view illustrating a solar cell panel according to another embodiment of the present invention.

Referring to FIG. 12 , in the solar cell panel 100 according to the present embodiment, at least one of the first and second cover members 110 and 120 may include portions having different thicknesses.

For example, as in the above-described embodiment, the sealing material 130 includes a central region CA and a reinforcing region EA1 located outside the central region CA and having a greater thickness than the central region CA. The provided outer area EA may be included. The first or second cover members 110 and 120 may include a central portion and an outer portion having a thickness smaller than that of the central portion. This is because the thickness of the outer portion of the first or second cover member 110 or 120 may be thinner than that of the central portion due to the rolling process or the like in the manufacturing process of the first or second cover member 110 or 120 composed of the glass substrate. am. In this case, the outer portion of the solar cell panel 100 may include a reinforcing portion having a thickness greater than that of the central portion, and may have the same thickness as the central portion of the solar cell panel 100 or may have a thickness smaller than the central portion.

12 illustrates that each of the first and second cover members 110 and 120 has an outer portion having a relatively thin thickness. However, the present invention is not limited thereto, and at least one of the first and second cover members 110 and 120 may include an outer portion having a relatively thin thickness. In addition, in FIG. 12 , it is exemplified that the outer portions positioned at both edges of the first or second cover members 110 and 120 have a relatively thin thickness. However, the present invention is not limited thereto, and the outer portion positioned at at least one of the edges of the first or second cover member 110 and 120 may have a relatively thin thickness. In this case, the reinforcing portion (reference numeral 132b of FIG. 8 or 10 , hereinafter the same) and the reinforcing area EA1 may be positioned in consideration of the position of the outer portion having a relatively thin thickness.

13 is a cross-sectional view illustrating a solar cell panel according to another embodiment of the present invention.

Referring to FIG. 13 , in the solar cell panel 100 according to the present embodiment, anti-reflection structures 110a and 120a for preventing reflection on the surfaces (particularly, inner surfaces) of the first or second cover members 110 and 120 . ) can be formed. The anti-reflection structures 110a and 120a may be formed of concavo-convex portions having various shapes and sizes capable of increasing surface roughness. The amount of light incident on the solar cell panel 100 may be maximized by the anti-reflection structures 110a and 120a to improve the output of the solar cell panel 100 .

However, when the anti-reflection structures 110a and 120a are provided, more leakage of the sealing material 130 may occur due to the pressure applied during the lamination process. In this structure, as in the above-described embodiment, the sealing material 130 includes the central area CA and the reinforcing area EA1 located outside the central area CA and having a greater thickness than the central area CA. The provided outer area EA may be included. Then, it is possible to effectively prevent the external leakage of the sealing material 130 in a structure in which the external leakage of the sealing material 130 may occur relatively in the vicinity of the edge.

13 illustrates that the first and second cover members 110 and 120 have uniform thicknesses, so that the solar cell panel 100 has a thickness similar to that of the sealing material 130 . However, the present invention is not limited thereto, and at least one of the first and second cover members 110 and 120 may include portions having different thicknesses as in the embodiment with reference to FIG. 12 . In addition, in FIG. 13 , the first and second cover members 110 and 120 each have anti-reflection structures 110a and 120a. However, the present invention is not limited thereto, and at least one of the first and second cover members 110 and 120 may have anti-reflection structures 110a and 120a. 13 illustrates that the anti-reflection structures 110a and 120a are formed on the inner surfaces of the first and second cover members 110 and 120 . However, the present invention is not limited thereto, and the anti-reflection structures 110a and 120a may also be formed on the outer surfaces of the first or second cover members 110 and 120 . Various other modifications are possible.

In the above-described embodiments, it is exemplified that at least a portion of the outer area EA (eg, the reinforcement area EA1 or the edge area EA2) has a greater thickness than the central area CA. However, the present invention is not limited thereto. Another embodiment will be described with reference to FIG. 14 .

14 is a cross-sectional view illustrating a solar cell panel according to another embodiment of the present invention.

14 , even when the first and/or second sealing materials 131 and 132 are formed using the reinforcing sealing material, the central area CA and the outer area EA have substantially the same thickness, so that the solar cell The thickness of the panel 100 may be uniform. In this case, the density of at least a portion of the outer area EA (eg, the reinforcement area EA1 or the edge area EA2) is greater than the density of the central area CA, or in the enlarged circle of FIG. 14 . As illustrated, an inclined portion having a varying step SP or thickness may be located in the outer region of the solar cell panel 100 . This is because, in the reinforcing sealant, the portion in which the relatively thick reinforcing portion 132b is located must be compressed to the same level as the other portions, so that the density of the portion increases or, thereby, a thickness change occurs. However, in this case, the effect of preventing leakage of the sealing material 130 to the outside or damage to the cover members 110 and 120 may not be sufficient because the buffer action by the reinforcing area EA1 is not sufficient during the lamination process. .

4 illustrates that three bus bar electrodes 42b are provided and three interconnectors 142 are provided based on one surface of the solar cell 10, but the present invention is not limited thereto. The number of the bus bar electrode 42b and the interconnectors 142 connected thereto one-to-one may be two or more.

For example, the interconnector 142 may be formed of a wire-shaped wiring material. This example will be described in detail with reference to FIGS. 15 and 16 . 15 is a front plan view illustrating a solar cell included in a solar cell panel and a wiring member connected thereto according to another embodiment of the present invention. 16 is a partial cross-sectional view of the solar cell shown in FIG. 15 and a wiring member connected thereto.

15 and 16 , the wire-shaped wiring material, for example, may be provided in a number greater than the number of ribbons (eg, 2 to 5) based on one surface of each solar cell 10 . . Then, it is possible to reduce the moving distance of the carrier by a large number of wiring members while minimizing light loss and material cost by the wiring member due to the small width. As described above, the efficiency of the solar cell 10 and the output of the solar panel 100 can be improved by reducing the moving distance of the carrier while reducing the light loss, and the productivity of the solar panel 100 can be reduced by reducing material costs due to wiring materials. can improve

For example, the number of busbar electrodes 42b and interconnectors 142 is 6 to 33 each (eg, 8 to 33, for example, 10 to 33, in particular, based on one surface) 10 to 15), and may be positioned at a uniform distance from each other.

In addition, the wire-shaped wiring material may have a smaller width than a ribbon having a relatively wide width (eg, greater than 1 mm). For example, the maximum width of the wiring member may be 1 mm or less (eg, 500 μm or less, more specifically, 250 to 500 μm). Here, the maximum width of the wiring material may mean the largest width of the width passing through the center of the wiring material. When the wiring material has the above-described maximum width, it can be smoothly attached to the solar cell 10 while maintaining a low resistance of the wiring material and minimizing light loss.

In order to prevent the process of attaching the wiring material to the solar cell 10 from becoming complicated when the number of wiring materials having a small width is used in large numbers, in this embodiment, the wiring material is applied to the core layer 142a and its surface. It may have a structure including the solder layer 142b to be formed. Then, a large number of wiring materials can be effectively attached by a process of applying heat and pressure while the plurality of wiring materials are mounted on the solar cell 10 .

The wiring material or the core layer 142a included therein and occupying most of the wiring material may include a rounded portion. That is, the cross section of the wiring member or the core layer 142a may include a portion in which at least a portion is circular, or a portion of a circle, an ellipse, or a portion of an ellipse, or a curved portion.

If it has such a shape, the wiring material is formed in a structure in which the solder layer 142b is located entirely on the surface of the core layer 142a, and the process of separately applying the solder material is omitted, and the wiring material is placed directly on the solar cell 10 to provide the wiring material. can be attached. Accordingly, the process of attaching the wiring member can be simplified. In addition, reflection or diffuse reflection is induced in the rounded portion of the wiring material, so that the light reflected on the wiring material is re-entered into the solar cell 10 to be reused. Accordingly, since the amount of light incident to the solar cell 10 is increased, the efficiency of the solar cell 10 and the output of the solar cell panel 100 may be improved. However, the present invention is not limited thereto. Accordingly, the wire constituting the wiring material may have a polygonal shape such as a quadrangle and may have various other shapes.

In this embodiment, the wiring material includes a core layer 142a made of metal, and a solder layer 142b formed on the surface of the core layer 142a and including a solder material to enable soldering with the electrodes 42 and 44. may include That is, the solder layer 142b may serve as a kind of adhesive layer. For example, the core layer 142a may include Ni, Cu, Ag, Al, etc. as a main material (eg, a material containing 50 wt% or more, more specifically, a material containing 90 wt% or more). The solder layer 142b may include a solder material such as Pb, Sn, SnIn, SnBi, SnPb, SnPbAg, SnCuAg, or SnCu as a main material. However, the present invention is not limited thereto, and the core layer 142a and the solder layer 142b may include various materials.

On the other hand, when the wiring material is attached to the solar cell 10 by the tabbing process, as shown in FIG. 16 , the shape of the solder layer 142b in the portion of the wiring material attached to or connected to the solar cell 10 is changed. .

More specifically, the wiring material may be attached to the bus bar electrode 42b (eg, a plurality of pad parts 422 and 442 positioned in the longitudinal direction of the bus bar electrode 42b) by the solder layer 142b. When the wiring material is attached to the solar cell 150 by the tabbing process, each solder layer 142b is formed on the first or second electrodes 42 and 44 (more specifically, the pad parts 422 and 442) during the tabbing process. The width of the solder layer 142b in a portion adjacent to each of the pad portions 422 and 442 or located between the pad portions 422 and 442 and the core layer 142a as the width of the solder layer 142b exceeds the pad portions 422 and 442. It can grow progressively as you go. For example, a portion of the solder layer 142b adjacent to the pad portions 422 and 442 may have a width equal to or greater than the width or diameter of the core layer 142a. In this case, the width of the solder layer 142b may be equal to or smaller than the width of the pad portions 422 and 442 .

In the structure including the plurality of wiring materials as described above, since the wiring material is positioned close to the edge of the solar cell 10 , more pressure may be applied to the solar cell 10 during the lamination process. In addition, since the plurality of wiring members have a rounded shape or have a relatively thick thickness compared to their width, the effect of dispersing pressure in the lamination process may be less than that of a ribbon having a flat shape. When the wiring material is provided in this way, the pressure dispersing effect in the lamination process is not large, so that more problems such as cracks in the solar cell 10 may occur during the lamination process. Since the sealing material 130 according to the present embodiment is applied to this structure, it is possible to effectively prevent problems such as cracks in the solar cell 10 during the lamination process.

This invention is supported by the national R&D project, and project specific number 20163010012430 (Ministry name: Ministry of Trade, Industry and Energy, research management agency: Korea Energy Technology Evaluation and Planning Institute) and project specific number 1415148844 (Ministry name: Ministry of Trade, Industry and Energy, research management) Specialized organization: Korea Industrial Technology Promotion Agency).

The features, structures, effects, etc. as described above are included in at least one embodiment of the present invention, and are not necessarily limited to one embodiment. Furthermore, features, structures, effects, etc. illustrated in each embodiment can be combined or modified for other embodiments by those of ordinary skill in the art to which the embodiments belong. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present invention.

100: solar panel
110: first cover member
120: second cover member
130: sealing material
10: solar cell
CA: Central Zone
EA: outer area
EA1: Reinforcement area
EA2: Edge area

Claims (20)

delete delete delete delete delete delete delete delete delete delete delete delete delete A plurality of solar cells, a first sealing material disposed on one surface of the plurality of solar cells and having a base portion and a reinforcing portion, a second sealing material located on the other surface of the solar cells, and a first sealing material located on the first sealing material forming a laminated structure by laminating a cover member and a second cover member positioned on the second sealing material; and
Laminating by applying heat and pressure to the laminated structure
including,
Forming the laminated structure comprises:
disposing the base portion having a first thickness over the plurality of solar cells;
A reinforcing portion having a second thickness different from the first thickness is disposed between a corner or an edge region of the first cover member and an outermost solar cell among the plurality of solar cells, disposing over the base portion to have an overlap portion overlapping a portion;
including,
The sealing material positioned between the first cover member and the second cover member includes a central region and an outer region provided with a reinforcing region located outside the central region and having a thickness greater than that of the central region,
The outer region may further include an edge region positioned outside the reinforcement region and having an edge having a smaller thickness than the reinforcement region. 15. The method of claim 14,
After the laminating step, the sealing material positioned between the first cover member and the second cover member is provided with a central region, and a reinforcing region located outside the central region and having a greater thickness than the central region. comprising an outer region; or
and an outer portion in which the solar cell panel is positioned outside the central portion and provided with a reinforcing portion having a thickness greater than that of the central portion. 15. The method of claim 14,
The ratio of the width of the overlapping portion to the width of the solar cell is 10% or more, or
A method for manufacturing a solar cell panel in which the width of the reinforcing portion is 5 cm or more. 15. The method of claim 14,
A method of manufacturing a solar cell in which a first area excluding a width of the reinforcing portion from a width of the base portion has a larger area than a second area corresponding to the width of the reinforcing portion. 15. The method of claim 14,
The method of manufacturing a solar cell panel in which the second thickness is smaller than the first thickness. 15. The method of claim 14,
wherein the reinforcing portion has a material different from the base portion or is formed separately and attached to or overlying the base portion. 20. The method of claim 19,
the reinforcing portion comprises a different material than the base portion;
The reinforcing portion is a method of manufacturing a solar cell panel having a lower hardness and higher elasticity than the base portion.

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