KR102156358B1 - Connecting member and solar cell module with the same - Google Patents

Abstract

The connection member according to an embodiment of the present invention is a connection member that connects a first electrode part of one solar cell among two adjacent rear junction solar cells to a second electrode part of another solar cell, and is bonded to the corresponding electrode part. A surface area expansion pattern is formed on a bonding surface of a bonding portion that includes a bonded portion and an unbonded portion that is not bonded to the electrode portion, and enlarges the surface area of the bonding surface. The surface area expansion pattern may include at least one concave portion and a convex portion formed around the concave portion, and the surface of the convex portion may be formed as a substantially flat surface. In addition, the solar cell module having the connection member includes: a plurality of solar cells including an electrode part for electrons (a first electrode part) and an electrode part for holes (a second electrode part) on a rear surface of a semiconductor substrate; And an adhesive positioned at the bonding portion and bonding the electrode portion to the bonding portion of the conductive metal.

Description

Connection member and solar cell module having the same {CONNECTING MEMBER AND SOLAR CELL MODULE WITH THE SAME}

The present invention relates to a connection member for electrically connecting two adjacent solar cells to each other and a solar cell module having the same.

Recently, as the depletion of existing energy resources such as oil and coal is predicted, interest in renewable energy to replace them has increased, and solar cells that produce electric energy from solar energy are attracting attention.

A typical solar cell includes a substrate and an emitter layer each made of semiconductors of different conductive types, such as p-type and n-type, and electrodes connected to the substrate and the emitter, respectively. At this time, a p-n junction is formed at the interface between the substrate and the emitter part.

When light is incident on such a solar cell, electrons inside the semiconductor become free electrons (hereinafter referred to as'electrons') due to the photoelectric effect, and electrons and holes are n according to the principle of pn junction. It moves toward the emitter part and the substrate, respectively, toward the p-type semiconductor and the p-type semiconductor. And the moved electrons and holes are collected by respective electrodes electrically connected to the substrate and the emitter.

On the other hand, in recent years, interdigitated back contact solar cells that improve the efficiency of solar cells by increasing the light-receiving area by forming the electronic collector and the hole collector on the rear surface of the substrate, that is, the rear surface where light does not enter, have been developed. Is being developed.

The technical problem to be achieved by the present invention is to provide a connection member having a novel structure and a solar cell module having the same.

The connection member according to an embodiment of the present invention is a connection member for connecting a first electrode part of one solar cell of two adjacent rear-bonded solar cells to a second electrode part of another solar cell, and is bonded to the corresponding electrode part. A surface area expansion pattern is formed on the bonding surface of the bonding portion facing the electrode portion, including a conductive metal including a bonded portion and an unbonded portion that is not bonded to the electrode portion. In addition, the uneven portion is not formed in the unjoined portion.

The surface area expansion pattern may include at least one concave portion and a convex portion formed around the concave portion, and the surface of the convex portion may be formed as a substantially flat surface.

For example, the conductive metal may include a main body extending in the first direction and forming the unjoined portion, and the bonding portion connected to the main body.

The conductive metal may include a first junction connected to both ends of the main body in the longitudinal direction, and a second junction connected to the center of the main body in the longitudinal direction, and the first junction and the second junction are orthogonal to the first direction. Can extend in any direction.

The main body of the conductive metal may have at least one slit, and the conductive metal may include a copper core and a solder located on at least one side of the copper core.

A solar cell module using a connection member provided with a conductive metal of this configuration is a plurality of solar cells including an electrode for electrons (first electrode) and an electrode for holes (second electrode) on the rear surface of a semiconductor substrate. battery; And an adhesive positioned at the bonding portion and bonding the corresponding electrode portion to the bonding portion of the conductive metal. The adhesive may be a solder or a conductive adhesive.

Accordingly, the concave portion of the surface area expansion pattern is filled with an adhesive, and the adhesive may be located between the surface of the convex portion and the surface of the corresponding electrode portion.

At this time, at least one slit provided in the main body of the conductive metal may be filled with a sealing material.

The solar cell module may further include an insulating film positioned between the electronic electrode part of one solar cell and the hole electrode part of the other solar cell, and the insulating film may contact the main body of the conductive metal.

As another example, the conductive metal may be composed of a strip-shaped main body extending in the first direction, and in this case, the joined portions and the unjoined portions may be alternately positioned in the first direction in the main body.

At this time, a surface area expansion pattern is formed on the junction. In addition, an enlarged surface area pattern may not be formed on the non-joined portion of the main body.

The non-bonded portion of the main body may have at least one slit, and the bonded portion of the main body may protrude toward the corresponding electrode portion compared to the non-bonded portion.

In addition, the conductive metal may include a copper core and solder positioned on at least one surface of the copper core.

A solar cell module using a connection member provided with a conductive metal having such a configuration includes a plurality of first electrodes extending in a first direction and a second electrode extending in the first direction and positioned between the first electrodes on a semiconductor substrate. A plurality of solar cells provided on the rear of the; And an adhesive positioned at the junction of the conductive metal and bonding the first electrode and the second electrode to the main body of the conductive metal.

At this time, one solar cell may include a first conductivity type substrate, and the other solar cell may include a second conductivity type substrate opposite to the first conductivity type. Accordingly, the first electrode of one solar cell and the second electrode of the other solar cell may be arranged in a straight line.

Accordingly, the concave portion of the surface area expansion pattern is filled with an adhesive, and the adhesive may be located between the surface of the convex portion and the surface of the corresponding electrode portion.

In addition, a sealing material may be filled in at least one slit formed in the unjoined portion of the main body.

The solar cell module of this configuration may further include an insulating film positioned between the first electrode of one solar cell and the second electrode of the other solar cell, and the insulating film may contact the unbonded portion of the main body. .

As another example, the conductive metal may be composed of two strip-shaped main bodies extending in a first direction and a bent portion bent in a direction inclined in the first direction to integrally connect the two main bodies. In each of the bodies, a bonded portion to be bonded to a corresponding electrode and an unbonded portion that is not bonded to the electrode may be alternately positioned in the first direction.

In this case, the main body of the conductive metal may have at least one slit, and the joined portion of the main body may protrude toward the corresponding electrode compared to the unjoined portion.

In addition, the conductive metal may include a copper core and a solder positioned on at least one surface of the copper core.

A solar cell module using a connection member provided with a conductive metal having such a configuration includes a plurality of first electrodes extending in a first direction and a second electrode extending in the first direction and positioned between the first electrodes on a semiconductor substrate. A plurality of solar cells provided on the rear of the; And an adhesive positioned at the junction and bonding the first electrode and the second electrode to the junction of the main body.

At this time, one solar cell and the other solar cell may each include the same conductive type substrate. Accordingly, the first electrode of one solar cell and the first electrode of the other solar cell may be arranged in a straight line.

Accordingly, the concave portion of the surface area expansion pattern is filled with an adhesive, and the adhesive may be located between the surface of the convex portion and the surface of the corresponding electrode portion.

In addition, a sealing material may be filled in at least one slit formed in the unjoined portion of the main body.

The solar cell module of this configuration may further include an insulating film positioned between the first electrode of one solar cell and the first electrode of the other solar cell, and the insulating film may contact the curved portion of the conductive metal.

A solar cell module according to another embodiment of the present invention includes a plurality of first electrodes and a plurality of second electrodes respectively extending in a first direction on a rear surface of a semiconductor substrate, and the second electrode is positioned between the first electrodes. A plurality of solar cells; And a connection member connecting a first electrode of one solar cell among two adjacent solar cells to a second electrode of another solar cell, wherein the connection member extends in a second direction orthogonal to the first direction. A conductive metal composed of a strip-shaped main body, and alternately positioned on the main body with a bonded portion bonded to the corresponding electrode and an unbonded portion not bonded to the electrode alternately in a second direction; And an adhesive which is located at the junction and bonds the first electrode of one solar cell and the second electrode of the other solar cell to the junction of the main body, and the bonding surface of the junction facing the electrode A surface area expansion pattern is formed to enlarge the surface area of the surface, and the joint portion of the main body is formed to protrude toward the corresponding electrode compared to the unjoined portion.

At this time, one solar cell and the other solar cell each include the same conductive type substrate, or each includes opposite conductive type substrates.

The surface area expansion pattern may include at least one concave portion and a convex portion formed around the concave portion, and the surface of the convex portion may be formed as a substantially flat surface.

Accordingly, the concave portion of the surface area expansion pattern is filled with an adhesive, and the adhesive may be located between the surface of the convex portion and the surface of the corresponding electrode portion.

The non-bonded portion of the conductive metal may have at least one slit, and the slit may be filled with a sealing material.

According to this feature, since the bonding portion of the conductive metal has a surface area expansion pattern, the contact area between the bonding surface of the conductive adhesive and the bonding portion increases, and thus electrical resistance decreases.

In addition, since the surface area expansion pattern includes convex portions positioned around the concave portions, spreading of the adhesive can be suppressed.

Therefore, since the bonding strength between the conductive metal and the adhesive is increased, bonding reliability is improved, the peeling of the conductive metal can be suppressed, and the charge transfer efficiency is improved.

In addition, when the joint portion of the main body protrudes compared to the non-joined portion, the stress applied to the main body in the modularization process can be reduced.

1 is a cross-sectional view of a main part of a solar cell module according to a first embodiment of the present invention.
FIG. 2 is an enlarged view in a hospital showing another embodiment of the enlarged surface area pattern shown in FIG. 1.
3 is a view showing the rear surface of the rear junction solar cell used in the solar cell module of FIG. 1.
4 is a partial cross-sectional view of FIG. 3 in the second direction (Y-Y').
5 is a plan view of a connection member used in the solar cell module of FIG. 1.
6 is a cross-sectional view of a main part of a solar cell module according to a second embodiment of the present invention.
7 is a plan view according to an embodiment of a connection member used in the solar cell module of FIG. 6.
8 is a cross-sectional view of a main part of a solar cell module according to a third embodiment of the present invention.
9 is a view showing a rear surface according to an embodiment of the rear junction solar cell used in the solar cell module of FIG. 8.
10 is a plan view illustrating a connection member used in the solar cell module of FIG. 8.
11 is a view showing a rear surface according to another embodiment of the rear junction solar cell used in the solar cell module of FIG. 8.
12 is a plan view illustrating a connection member used in a solar cell module having a rear junction solar cell of FIG. 11.
13 is a cross-sectional view of a main part of a solar cell module according to a fourth embodiment of the present invention.
14 is a diagram illustrating a rear surface according to an embodiment of the rear junction solar cell used in the solar cell module of FIG. 13.

In the present invention, various modifications may be made and various embodiments may be provided, and specific embodiments will be illustrated in the drawings and described in detail in the detailed description. This is not intended to limit the present invention to a specific embodiment, it can be understood to include all changes, equivalents, or substitutes included in the spirit and scope of the present invention.

In describing the present invention, terms such as first and second may be used to describe various components, but the components may not be limited by the terms. These terms may be used only for the purpose of distinguishing one component from another component.

For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

The term “and/or” may include a combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being "connected" or "coupled" to another component, it is said that it may be directly connected or coupled to the other component, but other components may exist in the middle. Can be understood.

On the other hand, when a component is referred to as being "directly connected" or "directly coupled" to another component, it may be understood that there is no other component in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions may include plural expressions unless the context clearly indicates otherwise.

In the present application, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or a combination thereof described in the specification, and one or more other features It may be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

In the drawings, the thicknesses are enlarged to clearly express various layers and regions. When a part of a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the case where the other part is "directly above", but also the case where the other part is in the middle. Conversely, when one part is "directly above" another part, it means that there is no other part in the middle.

Unless otherwise defined, all terms, including technical or scientific terms, used herein may have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

Terms as defined in a commonly used dictionary may be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in this application, interpreted as an ideal or excessively formal meaning. May not be.

In addition, the following embodiments are provided to more completely explain to those with average knowledge in the art, and the shapes and sizes of elements in the drawings may be exaggerated for clearer explanation.

Then, the present invention will be described with reference to the accompanying drawings.

In the following examples, a back junction solar cell is described for a hole electrode, an electron electrode, a hole current collector, and an electronic current collector all located on the rear surface of the semiconductor substrate, but the present invention relates to a hole electrode (or an electron electrode). ) Is located on the front side of the semiconductor substrate and can be applied to the solar cell of the MWT (Metal Wrap Through) structure where the electron electrode (or hole electrode), the hole current collector, and the electronic current collector are located on the back side of the semiconductor substrate. .

In addition, it can be applied to a solar cell having a pad part connected to an electrode instead of a current collector. At this time, the bonding portion of the connecting member is bonded to the pad portion.

FIG. 1 is a cross-sectional view of a main part of a solar cell module according to a first embodiment of the present invention, and FIG. 2 is an enlarged view showing another embodiment of the surface area enlargement pattern shown in FIG. 1.

And FIG. 3 is a view showing the rear surface of the rear junction solar cell used in the solar cell module of FIG. 1, FIG. 4 is a partial cross-sectional view in the second direction (Y-Y′) of FIG. 3, and FIG. 5 is It is a plan view of a connecting member used in a battery module.

First, the rear junction solar cell will be described with reference to FIGS. 3 and 4. The rear junction solar cell 100 includes a semiconductor substrate 110 of a first conductivity type, a light receiving surface of the semiconductor substrate 110, for example, a front surface. The front dielectric layer 120 formed on the surface), the antireflection film 130 formed on the front dielectric layer 120, and the other side of the semiconductor substrate 110, that is, the back surface, are formed with a high concentration of impurities of the first conductivity type. Impurities of the second conductivity type, which are formed on the rear surface of the semiconductor substrate 110 at positions adjacent to the first doped portion 141 and the first doped portion 141 that are doped with, are doped with a high concentration. The second doped portion 142, the rear dielectric layer 150 exposing a portion of the first doped portion 141 and the second doped portion 142, and the first doped portion 141 exposed by the rear dielectric layer 150 ), a plurality of electron electrodes 160 electrically connected to, a plurality of hole electrodes 170 electrically connected to the second doped portion 142 exposed by the rear dielectric layer 150, and a plurality of electron electrodes It includes an electron current collecting unit 180 connecting one end of the 160 and a hole current collecting unit 190 connecting one end of the plurality of hole electrodes 170.

The light-receiving surface of the semiconductor substrate 110 is formed as a texturing surface having a plurality of irregularities 111. Accordingly, the front dielectric layer 120 and the antireflection layer 130 are also formed as texturing surfaces.

The semiconductor substrate 110 is made of a first conductivity type, for example, n-type monocrystalline silicon. However, unlike this, the semiconductor substrate 110 may have a p-type conductivity type and may be made of polycrystalline silicon. In addition, the semiconductor substrate 110 may be made of a semiconductor material other than silicon.

Since the light-receiving surface of the semiconductor substrate 110 is formed as a texturing surface having a plurality of irregularities 111, the absorption rate of light is increased, thereby improving the efficiency of the solar cell.

The front dielectric layer 120 formed on the light-receiving surface of the semiconductor substrate 110 having a plurality of irregularities 111 formed thereon contains impurities of pentavalent elements such as phosphorus (P), arsenic (As), and antimony (Sb). ) May be a doped film with a higher concentration, and may act as a front surface field (FSF) similar to a back surface field (BSF). Accordingly, electrons and holes separated by the incident light are prevented from being recombined on the light-receiving surface of the semiconductor substrate 110 and disappearing.

The antireflection film 130 formed on the surface of the front dielectric layer 120 is made of a silicon nitride film (SiNx) or a silicon oxide film (SiO ₂ ). The antireflection film 130 reduces the reflectivity of incident sunlight and increases selectivity in a specific wavelength region, thereby increasing the efficiency of the solar cell.

The plurality of first doped portions 141 formed on the rear surface of the semiconductor substrate 110 are doped with an n-type impurity higher than that of the semiconductor substrate 110, and the plurality of second doped portions 142 contain p-type impurities. It is highly doped. Accordingly, the second doped portion 142 forms a p-n junction with the n-type semiconductor substrate 110.

The first doped portion 141 and the second doped portion 142 act as a passage for carriers (electrons and holes).

The rear dielectric layer 150 exposing a portion of the first doped portion 141 and the second doped portion 142 may be formed of a silicon oxide layer (SiO ₂ ), a silicon nitride layer (SiNx), or a combination thereof.

The rear dielectric layer 150 may act as a BSF that prevents carriers separated into electrons and holes from being recombined and reflects the incident light into the solar cell so as not to be lost to the outside, thereby reducing the amount of light lost to the outside.

The rear dielectric layer 150 may be formed as a single layer, but may have a multilayer structure such as a double layer or a triple layer.

An electron electrode 160 is formed on the first doped portion 141 not covered with the rear dielectric layer 150 and the rear dielectric layer 150 adjacent to the first doped portion 141, and is formed as the rear dielectric layer 150. A hole electrode 170 is formed on the uncovered second doped portion 142 and the rear dielectric layer 150 adjacent to the second doped portion 142.

At this time, the electron electrode 160 and the hole electrode 170 each extend in a first direction (X-X'), and the hole electrode 170 is a first direction orthogonal to the first direction (X-X'). It is alternately positioned with the electron electrode 160 in two directions (Y-Y'). Therefore, the hole electrode 170 is positioned between the electron electrode 160.

In addition, among the first doped portions 141 that are not covered with the rear dielectric layer 150, the electron collector 180 electrically connecting one end of the plurality of electron electrodes 160 in the vertical direction of FIG. 1 Among the second doped portions 142 that are formed and not covered with the rear dielectric layer 150, a hole collector 190 is formed in the vertical direction of FIG. 1 to electrically connect the plurality of hole electrodes 170 to each other. .

Here, the electron electrode 160 and the electron current collector 180 constitute an electronic electrode part, and the hole electrode 170 and the hole current collector 190 constitute a hole electrode part.

The electron electrode 160 and the electronic current collector 180 are electrically connected to the first doped part 141, and the hole electrode 170 and the hole current collector 190 are the second doped part 142. Is electrically connected to

At this time, the electron electrode 160 and the hole electrode 170 extend parallel to each other in the second direction (Y-Y') at a predetermined interval, and the electron current collector 180 and the hole current collector 190 ) Are formed side by side on both the left and right sides of the semiconductor substrate 110.

As described above, since a portion of the electron electrode 160 and the hole electrode 170 overlaps a portion of the rear dielectric layer 150, the contact resistance and series resistance with the doped portion are reduced, thereby increasing the cell efficiency.

In the above, it has been described as an example having an electron current collector 180 connected to the electron electrode 160 and a hole current collector 190 connected to the hole electrode 170, but the electron current collector 180 and It is also possible to provide a pad part (not shown) in place of the hole current collecting part 190.

The solar cell module of FIG. 1 including a rear junction solar cell having this configuration includes a connection member for electrically connecting two adjacent rear junction solar cells to each other. In describing the present embodiment, one of two adjacent rear junction solar cells is referred to as a first solar cell 100A, and the other solar cell is referred to as a second solar cell 100B.

The connection member is used to connect the electron current collector 180 of the first solar cell 100A adjacent to each other to the hole current collector 190 of the second solar cell 100B.

In this embodiment, the connection member 200 includes a conductive metal (CM) including a bonded portion BP bonded to the corresponding electrode portion and a non-bonded portion NBP not bonded to the electrode portion.

As shown in FIGS. 1 and 5, the conductive metal CM extends in the second direction (Y-Y') and forms a non-joined portion NBP, a main body (MB), and a main body ( MB) located at both ends and connected in the first direction (X-X'), two first bonding portions (FBP), and located in the longitudinal center of the main body MB, and the main body MB It may include a second bonding portion (SBP; Second Bonding Portion) orthogonal to. In this case, the first junction part FBP and the second junction part SBP extend in the second direction Y-Y'.

In addition, a surface area expansion pattern CP is formed on the bonding surface of the bonding portions FBP and SBP of the conductive metal CM, that is, the surface facing the electrode portion, and the surface area expansion pattern CP is It includes at least one concave portion CP1 and a convex portion CP2 formed around the concave portion CP1.

The surface of the convex portion CP2 may be formed as a substantially flat surface, as shown in FIGS. 1 and 2. Here,'substantially flat' refers to a state in which there is no artificially formed groove-shaped structure such as the concave portion CP1.

The concave portion CP1 may include a plurality of fine irregularities CP1-1 as shown in FIG. 1, or may include a groove CP1-2 having a semicircular cross-sectional shape or a polygonal groove as shown in FIG. 2. have.

In addition, the surface area expansion pattern CP may not be formed in the non-bonded portion NBP of the conductive metal.

The convex portion CP2 of the surface area expansion pattern CP may be formed by forming the concave portion CP1 in a state immersed from the surface of the bonding surface of the bonding portion BP.

Although not shown, the conductive metal CM may include a copper core and a solder positioned on at least one surface of the copper core.

1 illustrates that the surface of the convex portion CP2 is higher than the peak of the fine irregularities CP1-1, but the height of the peak of the convex portion CP2 and the fine irregularities CP1-1 are the same. can do.

Therefore, the adhesive CA applied to the surface area expansion pattern CP of the bonding portions FBP and SBP is the bonding area with the bonding portions FBP and SBP due to the plurality of fine irregularities CP1-1 provided in the recess CP1. Increases.

Further, the spreading phenomenon of the adhesive CA is suppressed by the protrusion CP.

Here, a conductive adhesive may be used as the adhesive CA, but the type of the adhesive is not limited as long as the electrode portion and the conductive metal CM can be electrically connected. In the following description, it will be described that the adhesive CA is a conductive adhesive.

An insulating film IF may be positioned between the electron current collector 180 of the first solar cell 100A and the hole current collector 190 of the second solar cell 100B.

The insulating film IF may be formed to have a combined thickness of the conductive adhesive CA and the current collector 180 or 190, but is thicker than the combined thickness of the conductive adhesive CA and the current collector 180 or 190 It can also be formed.

When the thickness of the insulating film IF is formed equal to the combined thickness of the conductive adhesive CA and the current collector 180 or 190, the side surfaces of the insulating film IF are conductive adhesive CA and the current collector ( 180 or 190), and the rear surface of the insulating film IF is in contact with the main body MB of the conductive metal CM.

In contrast, when the thickness of the insulating film IF is thicker than the combined thickness of the conductive adhesive CA and the current collector 180 or 190, the side surface of the insulating film IF is the substrate 110 and the conductive adhesive. (CA) and the side surface of the current collector 180 or 190, and the rear surface of the insulating film IF is in contact with the main body MB of the conductive metal (CM).

The insulating film IF may be made of a resin made of a material that is not deformed even at a temperature at which the modularization process of the solar cell module proceeds, for example, at a temperature of 300°C or higher, preferably 200°C or higher.

When the first solar cell 100A and the second solar cell 100B are electrically connected using the connection member of this configuration, the first junction part FBP and the first junction located on the left side of the main body MB in FIG. 2 The junction (SBP) is electrically connected to the electronic current collector 180 of the first solar cell (100A), the first junction (FBP) and the second junction (SBP) located on the right side of the main body (MB) Is electrically connected to the hole current collector 190 of the second solar cell 100B.

In order to electrically connect the first junction (FBP) and the second junction (SBP) of the main body (MB) to the current collector 180 or 190, a conductive adhesive (CA) is used in this embodiment, and a conductive adhesive (CA) is applied on the surface area expansion pattern CP provided in the junction portions FBP and SBP.

Although not shown, the conductive adhesive CA may include a thermosetting resin and a plurality of conductive particles dispersed in the resin.

At this time, the thermosetting resin of the conductive adhesive (CA) is used to bond the bonding portions (FBP, SBP) to the corresponding current collector 180 or 190, and a plurality of conductive particles are used to bond the bonding portions (FBP, SBP) and the corresponding current collector 180 or 190) is used to electrically connect.

Therefore, according to this embodiment, the first solar cell 100A and the second solar cell 100B are the electronic current collector 180 of the first solar cell 100A → conductive adhesive (CA) → first and second 2 Junction (FBP, SBP) → main body (MB) → first and second junction (FBP, SBP) → conductive adhesive (CA) → current path of the current collector 190 for holes of the second solar cell 100B It is electrically connected according to the (current path).

Meanwhile, in FIG. 4, reference numeral 200 denotes a back sheet positioned on the rear surface of the solar cell module, and reference numeral 300 denotes a sealing material positioned between the solar cell and the rear sheet.

In the above-described first embodiment, it has been described as an example that the current collectors 180 and 190 are bonded to the bonding portion BP of the conductive metal CM by a conductive adhesive CA, but in the solar cell, the bonding portion BP is bonded. It may be provided with a separate pad. In this case, the bonding portion BP is bonded to the pad.

Hereinafter, a solar cell module according to a second embodiment of the present invention will be described with reference to FIGS. 6 and 7.

6 is a cross-sectional view of a main part of the solar cell module, and FIG. 7 is a plan view according to an embodiment of a connection member used in the solar cell module of FIG. 6.

6 and 7, in the connection member according to the present embodiment, the main body MB of the conductive metal CM may have at least one slit SL.

As described above, when the conductive metal CM includes the slit SL, less thermal expansion of the conductive metal CM occurs in the modularization process than when the slit SL is not present.

Then, the sealing material 300 is filled in the slit SL.

Accordingly, according to the present embodiment, the first solar cell 100A and the second solar cell 100B are electrically connected according to the same current path as the embodiment of FIG. 1.

Hereinafter, a solar cell module according to a third embodiment of the present invention will be described with reference to FIGS. 8 to 10.

FIG. 8 is a cross-sectional view of a main part of a solar cell module according to a third embodiment of the present invention, and FIG. 9 is a view showing a rear surface according to an embodiment of a rear junction solar cell used in the solar cell module of FIG. 8. And FIG. 10 is a plan view illustrating a connection member used in the solar cell module of FIG. 8.

First, referring to FIG. 9, the rear junction solar cell used in the solar cell module according to the present embodiment will be described. Unlike the rear junction solar cell shown in FIG. 3, the rear junction solar cell shown in FIG. It does not include a current collector 180 for a hole and a current collector 190 for holes.

In addition, the first solar cell 100A is formed of a first conductivity type, for example, an N-type substrate, and the second solar cell 100B is a second conductivity type opposite to the first conductivity type, for example a P-type. It is formed as a substrate.

Therefore, in the second solar cell 100B produced using the same process as the first solar cell 100A, unlike the first solar cell 100A, the position of the electron electrode 160 of the first solar cell 100A The hole electrode 170 is formed in, and the electron electrode 160 is formed at the position of the hole electrode 170 of the first solar cell 100A.

Accordingly, when the first solar cell 100A and the second solar cell 100B are alternately disposed, the electron electrode 160 of the first solar cell 100A is used for holes of the second solar cell 100B. The electrode 170 is disposed in a straight line, and the hole electrode 170 of the first solar cell 100A is disposed in a straight line with the electron electrode 160 of the second solar cell 100B.

Therefore, it is not possible to electrically connect the two solar cells using the connection member described in the above-described embodiments.

In this way, in the case of manufacturing a solar cell module using a rear junction solar cell of a non-bus structure from which the electronic current collector 180 and the hole current collector 190 are removed, the left side of FIG. 9 The electron electrode 160 of the first solar cell 100A shown in is connected to the hole electrode of the second solar cell 100B shown on the right side, and the electron electrode 160 of the second solar cell 100B ) To the hole electrode of another first solar cell (not shown) located on the right side of the second solar cell, the connection member is a conductive metal consisting of a main body (MB) in the shape of a strip extending in the first direction. (CM) is provided.

At this time, on the main body MB, the bonded portions BP and the non-bonded portions NBP are alternately positioned in the first direction (X-X'), and a surface area enlarged pattern CP is formed on the bonded portion BP, The surface area expansion pattern CP may not be formed in the non-joined portion NBP.

In addition, as shown in FIG. 8, the bonded portion BP of the main body MB may protrude toward the corresponding electrode 160 or 170 compared to the unbonded portion NBP.

As described above, when the bonded portion BP is formed to protrude toward the corresponding electrode compared to the non-bonded portion NBP, stress applied to the main body MB in the modularization process can be reduced.

Although not shown, the conductive metal CM may include a copper core and a solder positioned on at least one surface of the copper core.

FIG. 10A shows a conductive metal CM in which an enlarged surface area pattern CP having a substantially rectangular planar shape is formed on the junction part BP of the main body MB, and FIG. 10B is A slit SL having an approximately circular planar shape in the non-joined portion NBP of the main body MB, and a surface area enlarged pattern CP having an approximately rectangular planar shape is formed at the junction portion BP of the main body MB The formed conductive metal CM is shown. When the conductive metal CM includes the slit SL, the sealing material 300 is filled in the slit SL as described in the embodiment of FIG. 6.

Meanwhile, an insulating film may be positioned between the electron electrode 160 of the first solar cell 100A and the hole electrode 170 of the second solar cell 100B as in the above-described embodiments.

The insulating film may be formed to have a combined thickness of the conductive adhesive CA and the electrode 160 or 170, but may be formed thicker than the combined thickness of the conductive adhesive CA and the electrode 160 or 170.

When the thickness of the insulating film is formed equal to the combined thickness of the conductive adhesive (CA) and the electrode 160 or 170, the side of the insulating film contacts the conductive adhesive (CA) and the electrode 160 or 170, The rear surface of the insulating film is in contact with the non-bonded portion (NBP) of the main body (MB).

In contrast, when the thickness of the insulating film is formed to be thicker than the combined thickness of the conductive adhesive (CA) and the electrode 160 or 170, the side surfaces of the insulating film are the substrate 110, the conductive adhesive (CA), and the electrode 160 Or 170), and the rear surface of the insulating film is in contact with the unbonded portion NBP of the main body MB.

The insulating film may be made of a resin made of a material that is not deformed even at a temperature at which the modularization process of the solar cell module proceeds, for example, at a temperature of 300°C or higher, preferably 200°C or higher.

Accordingly, according to this embodiment, the first solar cell 100A and the second solar cell 100B are the electrode 160 for electrons of the first solar cell 100A → conductive adhesive (CA) → main body (MB) → Conductive adhesive (CA) → Electrically connected according to a current path of the hole electrode 170 of the second solar cell 100B.

Hereinafter, a solar cell module according to another embodiment of the present invention will be described with reference to FIGS. 11 and 12.

FIG. 11 is a view showing the rear surface according to another embodiment of the rear junction solar cell used in the solar cell module of FIG. 8, and FIG. 12 is a view showing a connection member used in the solar cell module having the rear junction solar cell of FIG. These are examples showing a plan view.

The rear junction solar cell used in the solar cell module of this embodiment does not include an electronic current collector 180 and a hole current collector 190 like the rear junction solar cell shown in FIG. 9.

However, unlike the rear junction solar cell shown in FIG. 9, the first solar cell 100A and the second solar cell 100B are each formed of the same conductivity type, for example, an N-type substrate.

Therefore, in the second solar cell 100B produced by using the same process as the first solar cell 100A, the electron electrode 160 is formed at the position of the electron electrode 160 of the first solar cell 100A. , The hole electrode 170 is formed at the position of the hole electrode 170 of the first solar cell 100A.

Accordingly, when the first solar cell 100A and the second solar cell 100B are alternately disposed, the electronic electrode 160 of the first solar cell 100A is used for the electron of the second solar cell 100B. The electrode 160 is disposed in a straight line, and the hole electrode 170 of the first solar cell 100A is disposed in a straight line with the hole electrode 170 of the second solar cell 100B.

However, in order to connect the first solar cell 100A and the second solar cell 100B in series, the electronic electrode 160 of the first solar cell 100A located on the left side of FIG. It should be connected to the hole electrode 170 of the battery 100B, and the electron electrode 160 of the second solar cell 100B is located on the right side of the second solar cell. 100A) should be connected to the hole electrode.

Therefore, in the solar cell module in which the first solar cells 100A and the second solar cells 100B are alternately arranged using substrates of the same conductivity type as in this embodiment, the connection member shown in FIG. Two solar cells cannot be electrically connected by using a strip-shaped connecting member extending in one direction.

Therefore, the connection member used in the solar cell module of this embodiment is to connect the electron electrode 160 of the first solar cell 100A to the hole electrode 170 of the second solar cell 100B, or 1 In order to connect the hole electrode 170 of the solar cell 100A with the electron electrode 160 of the second solar cell 100B, the two main bodies MB extending in the first direction and It has a conductive metal (CM) composed of a bending portion (BDP) that is bent in an inclined direction at a certain angle (θ) in the first direction (X-X') and connects the two main bodies MB integrally. do.

At this time, on the two main bodies MB, the bonded portion BP and the non-bonded portion NBP are alternately positioned in the first direction (X-X'), and a surface area enlarged pattern CP is formed in the bonded portion BP. And, the surface area expansion pattern CP is not formed in the non-joined portion NBP.

In addition, as shown in FIG. 8, the bonded portion BP of the main body MB may protrude toward the corresponding electrode 160 or 170 compared to the unbonded portion NBP.

As described above, when the bonded portion BP is formed to protrude toward the corresponding electrode compared to the non-bonded portion NBP, stress applied to the main body MB in the modularization process can be reduced.

Although not shown, the conductive metal CM may include a copper core and a solder positioned on at least one surface of the copper core.

Figure 12 (a) shows a conductive metal (CM) in which a surface area enlarged pattern (CP) having a substantially rectangular planar shape is formed on the junction part (BP) of the main body (MB), and (b) of FIG. A slit SL having an approximately circular planar shape in the non-joined portion NBP of the main body MB, and a surface area enlarged pattern CP having an approximately rectangular planar shape is formed at the junction portion BP of the main body MB The formed conductive metal CM is shown. When the conductive metal CM includes the slit SL, the sealing material 300 is filled in the slit SL as described in the embodiment of FIG. 6.

Accordingly, according to the present embodiment, the first solar cell 100A and the second solar cell 100B are electrode 160 for electrons of the first solar cell 100A → conductive adhesive (CA) → conductive metal (CM) → Conductive adhesive (CA) → Electrically connected according to a current path of the hole electrode 170 of the second solar cell 100B.

In the above-described third embodiment, it has been described that the connection member extends in the same direction as the extension direction of the electrode to connect the first electrode of the first solar cell to the second electrode of the second solar cell.

However, the connecting member may extend in a direction orthogonal to the first electrode and the second electrode to connect the first electrode of the first solar cell and the second electrode of the second solar cell.

This embodiment will be described with reference to FIGS. 13 and 14. 13 is a cross-sectional view of a main part of a solar cell module according to a fourth embodiment of the present invention, and FIG. 14 is a view showing a rear surface according to an embodiment of a rear junction solar cell used in the solar cell module of FIG. 13.

The first solar cell 100A and the second solar cell 100B used in the solar cell module of the present embodiment may be formed of substrates of opposite conductivity types, such as the rear junction solar cell shown in FIG. Like the rear junction solar cell shown in Fig. 11, each of the substrates of the same conductivity type may be formed.

However, in the solar cell module of this embodiment, the first solar cell 100A and the second solar cell 100B are different from those shown in Figs. 9 and 11 described above, the first electrode 160 and the second electrode ( 170) are respectively disposed to extend in the second direction (Y-Y').

When the first solar cell 100A and the second solar cell 100B are disposed as described above, as shown in FIG. 10, the first solar cell 100A and the second solar cell 100B extend in the first direction X-X′, and the junction portion BP is an unbonded portion. Compared to (NBP), the first electrode 160 of the first solar cell 100A is connected to the first electrode 160 of the second solar cell 100B by using a connecting member including a belt-shaped conductive metal CM protruding toward the corresponding electrode. 2 Can be connected to the electrode 170.

That is, in the region where some of the conductive metal CM overlaps with the first solar cell 100A shown on the left side of FIG. 14, the junction part is at a position overlapping the second electrode 170 of the first solar cell 100A. BP), and in a region overlapping with the second solar cell 100B shown on the right, a junction portion BP is provided at a position overlapping with the first electrode 160 of the second solar cell 100B. In addition, the surface area expansion pattern CP is positioned at the junction part BP.

Accordingly, the first electrode 160 of the first solar cell 100A shown on the left side of FIG. 14 and the second electrode 170 of the second solar cell 100B shown on the right contact the sealing material 300, respectively. Therefore, it is not electrically connected to the conductive metal CM.

In addition, in the area where the other part of the conductive metal overlaps the second solar cell shown on the right side of FIG. 14, a junction is provided at a position overlapping the second electrode of the second solar cell, and the illustration located on the right side of the second solar cell In a region overlapping with the other first solar cell, the junction is provided at a position overlapping with the first electrode of the first solar cell.

Accordingly, the first electrode 160 of the second solar cell 100B shown on the right side of FIG. 14 and the second electrode of the other first solar cell not shown on the right side of the second solar cell 100B are Since each of them contacts the sealing material 300, they are not electrically connected to the conductive metal CM.

In this manner, the second electrode 170 of the first solar cell 100A is electrically connected to the first electrode 160 of the second solar cell 100B.

The solar cell module according to the present embodiment may also include an insulating film as in the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

100A: first solar cell 100B: second solar cell
CM: conductive metal CA: conductive adhesive
MB: main body BP: joint
FBP: first junction SBP: second junction
NBP: unjoined part IF: insulating film
CP: surface area expansion pattern CP1: concave
CP2: Iron part

Claims (42)

delete delete delete delete delete delete delete delete delete delete delete delete delete A plurality of solar cells having an electron electrode portion and a hole electrode portion on the rear surface of the semiconductor substrate;
A conductive connecting member connecting the electron electrode of one solar cell to the hole electrode of the other solar cell among two adjacent solar cells
Including, the conductive connection member,
A conductive metal comprising a main body extending in a first direction and forming an unjoined portion, and a joint portion protruding from and connected to the main body; And
An adhesive positioned at the junction and bonding the electrode portion to the junction of the conductive metal
Including,
A surface area expansion pattern including a convex portion forming a bonding surface of the convex portion and a concave portion immersed from the surface of the convex portion is formed on the bonding portion facing the electrode portion,
The convex portion surrounds the concave portion,
The surface area expansion pattern is not formed on the unjoined portion,
An insulating film (IF) extending between the two adjacent solar cells and extending to an end of the rear surface of each solar cell and positioned between each solar cell and a conductive connector, wherein the insulating film is a solar cell in contact with the main body module. delete In clause 14,
A solar cell module in which a plurality of fine irregularities are formed in the concave portion and the adhesive is filled. In paragraph 16,
The surface of the bonding surface is formed as a substantially flat surface, and the adhesive is also located between the surface of the bonding surface and the surface of the corresponding electrode part. In any one of claims 14, 16 and 17,
The conductive metal includes a first junction connected to both ends of the main body in the longitudinal direction, and a second junction connected to a central portion in the length direction of the main body, and the first junction and the second junction are in the first direction. A solar cell module extending in a second orthogonal direction. In paragraph 18,
The non-bonded portion of the main body has at least one slit, and the slit is filled with a sealing material. In paragraph 18,
The solar cell module further comprises an insulating film positioned between the electronic electrode part of the one solar cell and the hole electrode part of the other solar cell, wherein the insulating film contacts the main body. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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