KR102132941B1 - Solar cell and solar cell module - Google Patents

Abstract

The present invention relates to solar cells and solar cell modules.
The solar cell module according to the present invention includes a plurality of first electrodes formed on a rear surface of a semiconductor substrate, a plurality of second electrodes formed on a rear surface of the semiconductor substrate, and a first auxiliary electrode and a first auxiliary connected to the plurality of first electrodes. A first solar cell and a second solar cell including an electrode pad, an insulating member having a second auxiliary electrode connected to a plurality of second electrodes, and a second auxiliary electrode pad; And the first auxiliary electrode pad of the first solar cell and the second auxiliary electrode pad of the second solar cell electrically connected to each other, or the second auxiliary electrode pad of the first solar cell and the first auxiliary electrode pad of the second solar cell. And an interconnector electrically connected to each other. An unevenness is formed on at least one of the bonding surfaces of the interconnector and the first and second auxiliary electrode pads.
In addition, the solar cell according to the present invention, the first auxiliary electrode pad and the second auxiliary electrode pad are connected to an interconnector connecting a plurality of solar cells to each other, and at least an interconnector in the first auxiliary electrode pad and the second auxiliary electrode pad An unevenness may be formed in a portion connecting with.

Description

Solar cell and solar cell module {SOLAR CELL AND SOLAR CELL MODULE}

The present invention relates to solar cells and solar cell modules.

A typical solar cell includes substrates and emitters made of semiconductors of different conductivity 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 portion.

In particular, in order to increase the efficiency of the solar cell, research and development of a back electrode type solar cell in which an n electrode and a p electrode are formed only on the back surface of the silicon substrate without forming an electrode on the light receiving surface of the silicon substrate are being conducted. Modularization technology in which a plurality of such back electrode type solar cell cells are connected and electrically connected is also in progress.

The module and the technology are representatively a method of electrically connecting a plurality of solar cell cells with a metal interconnect, and a method of electrically connecting a wiring board with pre-wired wiring.

An object of the present invention is to provide a solar cell and a solar cell module.

The solar cell module according to the present invention includes a plurality of first electrodes formed on a rear surface of a semiconductor substrate, a plurality of second electrodes formed on a rear surface of the semiconductor substrate, and a first auxiliary electrode and a first auxiliary connected to the plurality of first electrodes. A first solar cell and a second solar cell including an electrode pad, an insulating member having a second auxiliary electrode connected to a plurality of second electrodes, and a second auxiliary electrode pad; And the first auxiliary electrode pad of the first solar cell and the second auxiliary electrode pad of the second solar cell electrically connected to each other, or the second auxiliary electrode pad of the first solar cell and the first auxiliary electrode pad of the second solar cell. And an interconnector electrically connected to each other. An unevenness is formed on at least one of the bonding surfaces of the interconnector and the first and second auxiliary electrode pads.

That is, unevenness may be formed in at least one of a portion connected to the first and second auxiliary electrode pads in the interconnector and a portion connected to the interconnector in each of the first and second auxiliary electrode pads.

In addition, the connection width between the interconnector and the first auxiliary electrode pad or the interconnector and the second auxiliary electrode pad may change as it progresses in the longitudinal direction of the interconnector.

Here, the connection width has a maximum connection width and a minimum connection width, and the maximum connection width and the minimum connection width can be repeated as the interconnection proceeds in the longitudinal direction.

Here, in the portion having the minimum connection width, the interconnector may be spaced apart from being connected to the first auxiliary electrode pad or the second auxiliary electrode pad.

In this case, a planar shape in which the interconnector and the first auxiliary electrode pad or the second auxiliary electrode pad are connected may include a curved surface.

Such a solar cell module includes: a front glass substrate positioned on a front surface of a cell string in which a first solar cell and a second solar cell are connected to each other by an interconnector; An upper encapsulant positioned between the front glass substrate and the cell string; A lower encapsulant located on the back side of the cell string; And a rear seat positioned on the rear of the lower encapsulant.

In addition, each of the first auxiliary electrode and the second auxiliary electrode extends in the first direction, and the first auxiliary electrode pad is connected to the end of the first auxiliary electrode extending in the first direction, and the second crossing the first direction It extends in the direction, the second auxiliary electrode pad is connected to the end of the second auxiliary electrode extending in the first direction, and may extend in the second direction.

At this time, each of the first auxiliary electrode pad and the second auxiliary electrode pad may not have a constant width in the first direction as it progresses in the second direction.

In addition, ends of each of the first auxiliary electrode pad and the second auxiliary electrode pad may include curved surfaces.

In addition, a plurality of first auxiliary electrode pads and a second auxiliary electrode pad may be respectively spaced apart, and the plurality of first auxiliary electrode pads may be spaced apart from each other, and the plurality of second auxiliary electrode pads may be spaced apart from each other.

Also, the width of the interconnector may or may not be constant as it progresses in the second direction.

In addition, the solar cell according to the present invention includes a semiconductor substrate; A plurality of first electrodes formed on a rear surface of the semiconductor substrate; A plurality of second electrodes spaced apart from the plurality of first electrodes on the rear surface of the semiconductor substrate and formed in parallel; The first auxiliary electrode connected to the plurality of first electrodes and the first auxiliary electrode pad connected to the ends of the first auxiliary electrode, the second auxiliary electrode connected to the plurality of second electrodes, and the ends of the second auxiliary electrode Insulating member including a second auxiliary electrode pad; includes, the first auxiliary electrode pad and the second auxiliary electrode pad is connected to an interconnector connecting a plurality of solar cells to each other, the first auxiliary electrode pad and the second auxiliary An unevenness may be formed in the electrode pad at least in a portion that is connected to the interconnector.

In addition, the width of each of the first auxiliary electrode pad and the second auxiliary electrode pad may be changed as it progresses in the longitudinal direction of the first auxiliary electrode pad and the second auxiliary electrode pad.

Here, each of the first auxiliary electrode and the second auxiliary electrode extends in the first direction, and the first auxiliary electrode pad is connected to an end of the first auxiliary electrode extending in the first direction, and a second crossing the first direction It extends in the direction, the second auxiliary electrode pad is connected to the end of the second auxiliary electrode extending in the first direction, and may extend in the second direction.

In addition, each of the first auxiliary electrode pad and the second auxiliary electrode pad may not have a constant width in the first direction as it progresses in the second direction.

At this time, the planar shape of each end of the first auxiliary electrode pad and the second auxiliary electrode pad may include a curved surface.

In addition, the first auxiliary electrode pad and the second auxiliary electrode pad may have a plurality, respectively, and the plurality of first auxiliary electrode pads may be spaced apart from each other, and the plurality of second auxiliary electrode pads may be spaced apart from each other.

As described above, the solar cell according to the present invention is a semiconductor substrate and the insulating member are connected to each other to form one integrated individual element, and thus, when some solar cells are damaged or defective during module formation, the solar cells are easily replaced. can do.

In addition, the solar cell and the solar cell module according to the present invention by changing the connection width between the interconnector and the first auxiliary electrode pad or the second auxiliary electrode pad changes as it progresses in the longitudinal direction of the interconnector, When connecting the solar cell to the solar cell, the phenomenon that the solar cell is bent by the thermal expansion coefficient between the insulating member and the first auxiliary electrode pad or the second auxiliary electrode pad can be further reduced.

1A to 2B are diagrams for describing a first embodiment of a solar cell module according to the present invention.
3 and 4 are diagrams for explaining an example of a solar cell applied to the solar cell module shown in FIG. 1.
5 is a view for explaining an example of the electrode pattern of the semiconductor substrate and the insulating member to be individually connected in the solar cells described in FIGS. 3 and 4, respectively.
6 is a view for explaining a state in which the semiconductor substrate and the insulating member shown in FIG. 5 are connected to each other.
7A is a cross-sectional view of the 7a-7a line in FIG. 6.
7B is a cross-sectional view of the line 7b-7b in FIG. 6.
FIG. 7C shows a cross-section of the line 7c-7c in FIG. 6.
8 is a view for explaining a second embodiment of the solar cell module according to the present invention.
9 is a view for explaining the insulating member of the solar cell applied to the solar cell module shown in FIG. 8.
10 is a view for explaining another example different from the first auxiliary electrode pad or the second auxiliary electrode pad illustrated in FIG. 9.
11 to 14 are views for explaining a third embodiment of the solar cell module according to the present invention.
15 is a view for explaining the overall cross-sectional structure of the solar cell module according to the first to third embodiments.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. In addition, in order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Hereinafter, the front surface may be one surface of the semiconductor substrate on which direct sunlight is incident or one surface of the front glass substrate, and the rear surface may be a semiconductor substrate and front glass substrate to which direct sunlight is not incident or reflected light other than direct sunlight may be incident. It may be the opposite side of one side.

Hereinafter, a solar cell module according to the present invention and a solar cell applied thereto will be described.

1A to 2B are diagrams for describing a first embodiment of a solar cell module according to the present invention.

Here, FIG. 1A is a shape in which two solar cells are connected by an interconnector (IC) in an example of the solar cell module according to the present invention, and FIG. 1B is an interconnector (IC) and the first and second assistants. It is a view for explaining an example in which irregularities are formed on at least one of the bonding surfaces of the electrode pads PP141 and PP142.

In addition, Figure 2a is a cross-sectional view along the line 2a-2a in Figure 1a, Figure 2b is a cross-sectional view along the line 2b-2b in Figure 1a.

1A to 2B, in the solar cell module according to the present invention, the semiconductor substrate 110 and the insulating member 200 are respectively connected to each other and are formed as a single solar cell (Cell). -a) and the second solar cell (Cell-b), and the first solar cell (Cell-a) and the second solar cell (Cell-b) may include an interconnector (IC) electrically connecting to each other. .

Here, each of the first solar cell (Cell-a) and the second solar cell (Cell-b), the semiconductor substrate 110 and the insulating member 200 are individually connected to form a single integrated individual cell Can be

Here, a plurality of first electrodes C141 and a plurality of second electrodes C142 may be formed on the rear surface of the semiconductor substrate 110, and the plurality of first electrodes C141 may be formed on the rear surface of the insulating member 200. The first auxiliary electrode P141, the first auxiliary electrode pad PP141, and the second auxiliary electrode P142 and the second auxiliary electrode pad PP142 connected to the plurality of second electrodes C142 may be formed. Can.

Here, the first electrode C141, the first auxiliary electrode P141, and the second electrode C142 and the second auxiliary electrode P142 may be connected by an electrode connecting material (ECA) made of a conductive material.

Here, each of the first auxiliary electrode P141 and the second auxiliary electrode P142 extends in the first direction x, and the first auxiliary electrode pad PP141 extends in the first direction x. It is connected to the end of the electrode P141, extends in a second direction y intersecting the first direction x, and the second auxiliary electrode pad PP142 is a second auxiliary extending in the first direction x. It is connected to the end of the electrode P142, and may extend in the second direction (y). The structure of such a solar cell will be specifically described in FIGS. 3 to 7C.

The interconnector IC is electrically connected to the first auxiliary electrode pad PP141 of the first solar cell and the second auxiliary electrode pad PP142 of the second solar cell by an interconnector ICA, or to the first solar cell. The second auxiliary electrode pad PP142 of the solar cell and the first auxiliary electrode pad PP141 of the second solar cell may be electrically connected to each other by an interconnector ICA.

On the other hand, in such a solar cell module, the solar cell module according to the present invention may be formed on the at least one of the bonding surface of the interconnector (IC) and the first and second auxiliary electrode pads (PP141, PP142).

As described above, when irregularities are formed on at least one of the bonding surfaces of the interconnector IC and the first and second auxiliary electrode pads PP141 and PP142, the bonding surfaces are increased by the irregularities, and, in addition, the interconnectors IC and First and second auxiliary electrode pads (PP141, PP142) protrusions and depressions formed by irregularities of each other are engaged with each other to further improve adhesion between the interconnector (IC) and the first and second auxiliary electrode pads (PP141, PP142). I can do it.

More specifically, as illustrated in (a) of FIG. 1B, irregularities are formed in a portion of the interconnector IC that is connected to at least the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142. In addition, irregularities may be formed in at least portions of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 that are connected to the interconnector IC.

As described above, when unevenness is formed in at least parts of the interconnector IC and the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142, the interconnector connection material as illustrated in FIG. 1B(b). By (ICA), the surface area of the parts connected to each other increases, and the protrusions and depressions of the irregularities are engaged with each other, so that the adhesive force between the interconnector IC and the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 Can be further improved.

At this time, the shape of the unevenness formed in the interconnector (IC), the first auxiliary electrode pad (PP141), and the second auxiliary electrode pad (PP142) is the first direction (x) and the cross-section is shown in Figure 1b (b) As described above, a plurality of protrusions and a plurality of depressions may be repeated, and each of these protrusions and depressions may have a shape extending in the second direction (y), and formed in the interconnector (IC). The protrusion or depression may be connected to correspond to the depression or protrusion formed in the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142.

Accordingly, the adhesive force in the first direction (x) can be further strengthened, and in the process of connecting the interconnector (IC), the first auxiliary electrode pad PP141 and the second auxiliary electrode pad due to a difference in thermal expansion coefficient Even if the length of the second direction (y) of the PP142 is partially changed, the influence on the adhesive force of the interconnector IC can be minimized.

As described above, the uneven structure formed on the junction surface of the interconnector IC or the first and second auxiliary electrode pads PP141 and PP142 is not only the first embodiment here, but also the second and third embodiments described later. Edo can be applied as is.

Here, the uneven structure formed on the junction surface of the interconnector (IC) may be formed by irradiating a laser beam on the junction surface of the interconnector (IC) and etching the junction surface of the interconnector (IC).

In addition, the concavo-convex structure formed on the bonding surfaces of the first and second auxiliary electrode pads PP141 and PP142 is formed by irradiating a laser beam on the bonding surfaces of the first and second auxiliary electrode pads PP141 and PP142, or an insulating member ( It may be formed by forming the first and second auxiliary electrode pads PP141 and PP142 as thin films on the surface of the insulating member 200 on which the unevenness is formed in the state where the unevenness is previously formed in 200).

In addition, the solar cell module according to the present invention, as shown in Figure 1a, the interconnector (IC) and the first auxiliary electrode (P141) or the interconnector (IC) and the second auxiliary electrode (P142) is connected to the width It may change as it progresses in the longitudinal direction (y) of the interconnector (IC).

Here, if the connection width of the interconnector (IC) and the first auxiliary electrode (P141) or the second auxiliary electrode (P142) can be changed as it progresses in the longitudinal direction (y) of the interconnector (IC) as follows It may be the same case.

(1) In the state in which the width of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 is changed to change along the longitudinal direction y of the interconnector IC, the width along the longitudinal direction is uniform. When connecting the interconnector (IC) to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142,

(2) In the state in which the width of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 along the longitudinal direction y of the interconnector IC is uniformly formed, the width along the longitudinal direction changes. When connecting the interconnector (IC) to the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142), and

(3) In addition, by mixing the cases of (1) and (2), the width of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 is the lengthwise direction of the interconnector IC (y It may be a case in which the interconnector IC having a width varying along the length direction is connected to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 in a state formed to be changed according to ).

Among the above cases, an example for the case (1) is described in FIGS. 1A to 10, and an example for the case (2) is described in FIGS. 11 to 14.

As shown in Figure 1a, the solar cell module according to the present invention is the first direction (x) in which the interconnector (IC) and the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142) are connected to each other. The width of may change as it progresses in the second direction (y), which is the longitudinal direction (y) of the interconnector (IC).

As an example, the width at which the interconnector IC and the first auxiliary electrode pad PP141 connect may be changed between WC1a and WC1b according to the longitudinal direction y of the interconnector IC, and the interconnector IC And the second auxiliary electrode pad PP142 may be changed between WC2a and WC2b according to the longitudinal direction y of the width interconnector IC connected to each other.

As described above, in the solar cell module according to the present invention, the width in which the interconnector (IC) and the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142) are connected is the longitudinal direction (y) of the interconnector (IC). ) When the interconnector IC is connected to the first solar cell (Cell-a) or the second solar cell (Cell-b) by gradually increasing or decreasing as it progresses in the second direction (y) , Due to the difference in the coefficient of thermal expansion of the insulating member 200 and the coefficient of thermal expansion of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 formed of a metallic material, it is possible to minimize the bending of the insulating member 200. have.

That is, when connecting the interconnector (IC) to each solar cell, by changing the connection width along the longitudinal direction (y) of the interconnector (IC), the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad ( PP142) may disperse the length of thermal expansion in the longitudinal direction (y) of the interconnector (IC), thereby, the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142) in the second direction (y ), the overall length of thermal expansion can be further reduced.

Due to this, it is possible to minimize damage to the semiconductor substrate 110 by minimizing the thermal expansion stress on the semiconductor substrate 110 integrally attached to the insulating member 200.

Here, the maximum connection widths WC1a and WC2a of the interconnector IC and the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may be up to 4 mm, and the minimum connection widths WC1b and WC2b are Unlike in Fig. 2B, it may or may not be connected. Accordingly, the interconnector IC may be spaced apart from being connected to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 in some sections along the longitudinal direction.

At this time, the maximum connection width (WC1a, WC2a) and the minimum connection width (WC1b, WC2b) may be repeated as it progresses in the second direction (y), which is the longitudinal direction of the interconnector (IC).

In addition, at this time, as illustrated in FIG. 1A, a plane shape in which the interconnector IC and the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 are connected may include a curved surface.

In addition, at this time, at this time, the width WI along the longitudinal direction y of the interconnector IC is constant, and the overlapping width of the interconnector IC and the insulating member 200 along the second direction y is also constant. In addition, the separation width of the interconnector (IC) and the semiconductor substrate 110 along the second direction (y) may be constant. In addition, unlike shown in FIGS. 1A to 2B, the interconnector (IC) and the semiconductor substrate 110 may be in a physically connected state to each other.

Hereinafter, an example of a solar cell applied to such a solar cell module will be described in more detail.

3 and 4 are views for explaining an example of a solar cell applied to the solar cell module shown in Figures 1a and 1b.

3 is an example of a partial perspective view of a solar cell according to an example of the present invention, and FIG. 4 is a cross-sectional view of the solar cell shown in FIG. 3 taken along line 4-4.

3 and 4, examples of the solar cell according to the present invention include a semiconductor substrate 110, an anti-reflection film 130, an emitter portion 121, a back surface field (BSF, 172), A plurality of first electrodes C141, a plurality of second electrodes C142, a first auxiliary electrode P141, and a second auxiliary electrode P142 may be included.

Here, the anti-reflection film 130 and the rear electric field portion 172 may be omitted, and also located between the anti-reflection film 130 and the semiconductor substrate 110 to which light is incident, and have the same conductivity as the semiconductor substrate 110. It is also possible to further include a front electric field portion (not shown), which is an impurity portion containing impurities of a higher concentration than the semiconductor substrate 110.

Hereinafter, an anti-reflection film 130 and a rear electric field 172 are included as an example, as illustrated in FIGS. 3 and 4.

The semiconductor substrate 110 may be a bulk semiconductor substrate 110 made of silicon of a first conductivity type, for example, an n-type conductivity type. The semiconductor substrate 110 may be formed by doping a first conductive type impurity on a wafer formed of silicon.

The upper surface of the semiconductor substrate 110 is textured to have a textured surface that is an uneven surface. The anti-reflection film 130 is positioned on the incident surface of the semiconductor substrate 110, may be formed of one layer or multiple layers, and may be formed of a hydrogenated silicon nitride film (SiNx:H) or the like. In addition, it is also possible that a front electric field or the like is further formed on the front surface of the semiconductor substrate 110.

The emitter parts 121 are spaced apart from each other in the rear surface of the semiconductor substrate 110 facing the front surface, and extend in parallel directions. A plurality of emitter parts 121 may be provided, and the plurality of emitter parts 121 may be a second conductive type opposite to the conductive type of the semiconductor substrate 110.

The plurality of emitter portions 121 may be formed by containing a p-type impurity of a second conductivity type, which is opposite to the conductivity type of the crystalline silicon semiconductor substrate 110, at a high concentration through a diffusion process.

A plurality of rear electric field parts 172 may be located inside the rear surface of the semiconductor substrate 110 and are formed to be spaced apart in a direction parallel to the plurality of emitter parts 121 and extend in the same direction as the plurality of emitter parts 121. have. Accordingly, as shown in FIGS. 3 and 4, the plurality of emitter portions 121 and the plurality of rear electric field portions 172 are alternately positioned on the rear surface of the semiconductor substrate 110.

The plurality of rear electric field parts 172 are impurities having a conductivity type that is the same as that of the semiconductor substrate 110, and impurities, for example, n++ parts, contained at a higher concentration than the semiconductor substrate 110. The plurality of rear electric field parts 172 may be formed by containing impurities (n++) of the same conductivity type as the crystalline silicon semiconductor substrate 110 at a high concentration through a diffusion process.

The plurality of first electrodes C141 are physically and electrically connected to the emitter part 121, respectively, and extend apart from each other along the emitter part 121. Therefore, when the emitter portion 121 extends in the first direction (x), the first electrode C141 may also extend in the first direction (x), and the emitter portion 121 may extend in the second direction (y). When extended to, the first electrode C141 may also extend in the second direction (y).

Further, the plurality of second electrodes C142 are physically and electrically connected to the semiconductor substrate 110 through the rear electric field portion 172, respectively, and extend along the plurality of rear electric field portions 172.

Accordingly, when the rear electric field portion 172 extends in the first direction (x), the second electrode C142 may also extend in the first direction (x), and the rear electric field portion 172 may rotate in the second direction ( When extending in y), the second electrode C142 may also extend in the second direction (y).

Here, the first electrode C141 and the second electrode C142 are physically separated from each other and electrically isolated on the rear surface of the semiconductor substrate 110.

Accordingly, the first electrode C141 formed on the emitter portion 121 collects charges, for example, holes, moved toward the emitter portion 121, and the second electrode formed on the rear electric field portion 172 ( C142) may collect electric charges, for example, electrons, which have moved toward the rear electric field 172.

The first auxiliary electrode P141 may be formed by being electrically connected to the rear surfaces of the plurality of first electrodes C141. The first auxiliary electrode P141 may be formed in plural.

Here, when the plurality of first auxiliary electrodes P141 are formed, the first auxiliary electrodes P141 may be formed in the same direction as the plurality of first electrodes C141 or may be formed in an intersecting direction.

The first auxiliary electrode P141 may be electrically connected to each other at a portion overlapping with the first electrode C141.

The second auxiliary electrode P142 may be formed by being electrically connected to the rear surfaces of the plurality of second electrodes C142. A plurality of second auxiliary electrodes P142 may also be formed.

Here, when a plurality of second auxiliary electrodes P142 are formed, the second auxiliary electrodes P142 may be formed in the same direction as the plurality of second electrodes C142 or may be formed in an intersecting direction.

As such, the second auxiliary electrode P142 may be electrically connected to each other at a portion overlapping the second electrode C142.

In addition, although FIG. 3 and FIG. 4 illustrate a plurality of first and second auxiliary electrodes P141 and P142 as an example, differently, the first auxiliary electrode P141 and the second auxiliary electrode ( P142) may be formed of a single sheet electrode.

Materials of the first auxiliary electrode P141 and the second auxiliary electrode P142 may include at least one of Cu, Au, Ag, and Al.

In addition, the aforementioned first auxiliary electrode P141 may be electrically connected to the first electrode C141 through an electrode connecting material (ECA) of a conductive material, and the second auxiliary electrode P142 may be an electrode connecting material (ECA) of a conductive material. ) May be electrically connected to the second electrode C142.

If the material of the electrode connecting material (ECA) is a conductive material, there is no particular limitation, but a conductive material having a melting point formed at a relatively low temperature of 130°C to 250°C is more preferable, for example, a solder paste. , Conductive adhesive containing metal particles, carbon nano tube (CNT), conductive particles containing carbon, wire, needle, and the like can be used.

In addition, an insulating layer IL preventing a short circuit may be positioned between the aforementioned first electrode C141 and the second electrode C142 and between the first auxiliary electrode P141 and the second auxiliary electrode P142. . The insulating layer IL may be an epoxy resin.

In addition, in FIGS. 3 and 4, only the first electrode C141 and the first auxiliary electrode P141 are overlapped, and the second electrode C142 and the second auxiliary electrode P142 are overlapped. Alternatively, the first electrode C141 and the second auxiliary electrode P142 may overlap, and the second electrode C142 and the first auxiliary electrode P141 may overlap. In this case, the insulating layer IL may be positioned between the first electrode C141 and the second auxiliary electrode P142 and between the second electrode C142 and the second auxiliary electrode P142 to prevent a short circuit. have.

The first auxiliary electrode P141 and the second auxiliary electrode P142 do not use a semiconductor manufacturing process, and may be formed by a heat treatment process that applies heat and pressure between 130°C and 250°C to the electrode connecting material (ECA). have.

In addition, although not illustrated in FIGS. 3 and 4, a first auxiliary electrode pad PP141 for serial connection of a solar cell may be electrically connected to an end of the first auxiliary electrode P141, and the second auxiliary electrode P141 may be formed. At the end of the auxiliary electrode P142, a second auxiliary electrode pad PP142 for series connection of a solar cell may be formed by being electrically connected. This will be described in detail below in FIG. 5.

The insulating member 200 may be disposed on the rear surfaces of the first auxiliary electrode P141 and the second auxiliary electrode P142.

The material of the insulating member 200 is not particularly limited as long as it is an insulating material, but the melting point of the insulating member 200 may be higher than that of the electrode connecting material (ECA). For example, the melting point of the insulating member 200 is 300° C. or higher. It may be formed of an insulating material. More specifically, as an example, it may be formed of at least one material of polyimide, epoxy-glass, polyester, BT (bismaleimide triazine) resin that is heat resistant to high temperatures.

The insulating member 200 may be formed in a flexible film form or may be formed in a rigid plate form without being flexible.

In the solar cell according to the present invention, the first auxiliary electrode P141 and the second auxiliary electrode P142 are formed on the front surface of the insulating member 200 in advance, and the plurality of first electrodes are formed on the rear surface of the semiconductor substrate 110. In a state in which the C141 and the plurality of second electrodes C142 are previously formed, the insulating member 200 and the semiconductor substrate 110 may be individually connected to each other to be formed as one individual element.

That is, the semiconductor substrate 110 that is attached to and connected to one insulating member 200 may be one, and such one insulating member 200 and one semiconductor substrate 110 may be attached to each other to form one integral individual. It can be formed of a device to form one solar cell.

More specifically, a plurality of formed on the rear surface of one semiconductor substrate 110 by a process of forming one insulating member 200 and one semiconductor substrate 110 by attaching each other to one integrated individual element. Each of the first electrode C141 and the plurality of second electrodes C142 is attached to the first auxiliary electrode P141 and the second auxiliary electrode P142 formed on the front surface of one insulating member 200 to be electrically connected to each other. Can. This will be described later in more detail.

In the solar cell according to the present invention, the thickness T2 of each of the first auxiliary electrode P141 and the second auxiliary electrode P142 is the thickness T1 of each of the first electrode C141 and the second electrode C142. ).

Thus, by making the thickness T2 of the first auxiliary electrode P141 and the second auxiliary electrode P142 larger than the thickness T1 of each of the first electrode C141 and the second electrode C142, solar cell manufacturing It is possible to shorten the process time, and to reduce the thermal expansion stress on the substrate more than to form the first electrode C141 and the second electrode C142 directly on the rear surface of the semiconductor substrate 110, so that the solar cell Can further improve the efficiency.

More specifically, it is as follows.

The emitter portion 121 formed on the rear surface of the semiconductor substrate 110, the rear electric field portion 172, the first electrode C141 connected to the emitter portion 172, and the second electrode connected to the rear electric field portion 172 (C142) may be formed by a semiconductor process, during such a semiconductor process, the first electrode (C141) and the second electrode (C142) is in direct contact or very close to the back surface of the semiconductor substrate 110, mainly plating, It can be formed by PVD deposition or high temperature heat treatment.

In this case, in order to sufficiently secure the resistances of the first electrode C141 and the second electrode C142, the thicknesses of the first electrode C141 and the second electrode C142 must be sufficiently thick.

However, when the thicknesses of the first electrode C141 and the second electrode C142 are thick, the thermal expansion coefficients of the first electrode C141 and the second electrode C142 including the conductive metal material are the semiconductor substrate 110. ) May be excessively larger than the coefficient of thermal expansion.

Therefore, during the process of forming the first electrode C141 and the second electrode C142 by a high-temperature heat treatment process on the rear surface of the semiconductor substrate 110, the first electrode C141 and the second electrode C142 may contract. At this time, since the semiconductor substrate 110 does not withstand the thermal expansion stress, the likelihood of cracks or cracks in the semiconductor substrate 110 increases, thereby reducing the yield of the solar cell manufacturing process, or Efficiency may be reduced.

In addition, when the first electrode C141 or the second electrode C142 is formed by plating or PVD deposition, the growth rate of the first electrode C141 or the second electrode C142 is very small, and thus the solar cell manufacturing process Time may be excessive.

However, the solar cell according to the present invention, the first electrode (C141) and the second electrode (C142) with a relatively small thickness (T1) on the back surface of the semiconductor substrate 110, the insulating member 200 of the After placing the first auxiliary electrode P141 and the second auxiliary electrode P142 formed of a relatively large thickness T2 on the front surface so as to overlap the first electrode C141 and the second electrode C142, the electrode connecting material ( ECA) is a heat treatment process that applies heat and pressure between 130°C and 250°C, which is relatively low, can be formed as one integrated individual device by attaching one insulating member 200 and one semiconductor substrate 110 to each other. Cracks or cracks may be prevented from occurring in the semiconductor substrate 110, and at the same time, resistance of an electrode formed on the rear surface of the semiconductor substrate 110 may be significantly reduced.

In addition, the solar cell according to the present invention can relatively minimize the thickness T1 of the first electrode C141 and the second electrode C142 to minimize the semiconductor manufacturing process time with a relatively long process time. In the heat treatment process of the first electrode (C141) and the first auxiliary electrode (P141), the second electrode (C142) and the second auxiliary electrode (P142) can be connected to each other, shortening the manufacturing process time of the solar cell more can do.

In this case, when the insulating member 200 adheres the first auxiliary electrode P141 and the second auxiliary electrode P142 to the first electrode C141 and the second electrode C142 formed on the rear surface of the semiconductor substrate 110, It serves to help the process more easily.

That is, the insulating member 200 in which the first auxiliary electrode P141 and the second auxiliary electrode P142 are formed on the rear surface of the semiconductor substrate 110 on which the first electrode C141 and the second electrode C142 are formed in the semiconductor manufacturing process. When attaching and connecting the entire surface of ), the insulating member 200 can help the alignment process or the adhesion process more easily.

In the solar cell according to the present invention manufactured with such a structure, holes collected through the first auxiliary electrode P141 and electrons collected through the second auxiliary electrode P142 are converted into power of the external device through an external circuit device. Can be used.

The operation of the solar cell having the rear junction structure is as follows.

When light is irradiated to the solar cell and passes through the anti-reflection layer 130 to enter the semiconductor substrate 110, electron-hole pairs are generated in the semiconductor substrate 110 by light energy.

These electron-hole pairs are separated from each other by a pn junction of the semiconductor substrate 110 and the emitter portion 121, and holes move toward a plurality of emitter portions 121 having a p-type conductivity type, and electrons are n-type. Moving toward the plurality of rear electric field portions 172 having a conductivity type, they are collected by the first auxiliary electrode P141 and the second auxiliary electrode P142, respectively. When the first auxiliary electrode P141 and the second auxiliary electrode P142 are connected by a conducting wire, a current flows, and this is used as power from the outside.

So far, the case where the semiconductor substrate 110 is a single crystal silicon semiconductor substrate 110 and the emitter portion 121 and the rear electric field portion 172 are formed through a diffusion process has been described as an example.

However, differently, a heterojunction solar cell in which the emitter portion 121 and the rear electric field portion 172 formed of amorphous silicon material are bonded to the crystalline semiconductor substrate 110, or the emitter portion 121 is placed on the front surface of the semiconductor substrate 110. The present invention can be equally applied to a solar cell having a structure that is located and connected to the first electrode C141 formed on the rear surface of the semiconductor substrate 110 through a plurality of via holes formed in the semiconductor substrate 110.

A solar cell having such a structure may connect adjacent solar cells to each other by an interconnector (IC), and accordingly, a plurality of solar cells may be connected in series.

Meanwhile, in such a structure, the pattern of the first electrode C141 and the second electrode C142 formed on the rear surface of the semiconductor substrate 110 and the first auxiliary electrode P141 formed on the front surface of the insulating member 200 ) And the second auxiliary electrode P142 will be described in more detail as follows.

FIG. 5 is a view for explaining an example of electrode patterns of the semiconductor substrate 110 and the insulating member 200 to be individually connected in the solar cells described with reference to FIGS. 3 and 4.

5A is a view for explaining an example of a pattern of the first electrode C141 and the second electrode C142 disposed on the rear surface of the semiconductor substrate 110, and FIG. 5B is a view of FIG. A) is a cross-sectional view along the line 5(b)-5(b), and FIG. 5(c) is a first auxiliary electrode P141 and a second auxiliary electrode P142 disposed on the front surface of the insulating member 200. 5(d) is a cross-sectional view taken along line 5(d)-5(d) in FIG. 5(c).

The front surface of one insulating member 200 as shown in (c) and (d) of FIG. 5 is located on the rear surface of one semiconductor substrate 110 as shown in (a) and (b) of FIG. 5. By being attached and connected, the solar cell according to the present invention can form one integrated individual element. That is, the insulating member 200 and the semiconductor substrate 110 may be coupled or attached 1:1.

At this time, as shown in (a) and (b) of FIG. 5, a plurality of first electrodes C141 and a plurality of second electrodes are provided on the rear surface of the semiconductor substrate 110 of the solar cell described with reference to FIGS. 3 and 4. (C142) may be spaced apart from each other and formed long in the first direction (x).

In addition, a plurality of first auxiliary electrodes P141 and a plurality of second auxiliary electrodes P142 are provided on the front surface of the insulating member 200 according to the present invention, as illustrated in FIGS. 5C and 5D. They may be spaced apart from each other and formed long in the first direction (x).

In addition, the first auxiliary electrode pad PP141 extending in the second direction (y) is further provided at the ends of the plurality of first auxiliary electrodes P141 formed in the first direction (x) on the front surface of the insulating member 200. The first auxiliary electrode pad PP141 may be connected to the ends of the plurality of first auxiliary electrodes P141.

In addition, at the ends of the plurality of second auxiliary electrodes P142 formed in the first direction (x) on the front surface of the insulating member 200, a second auxiliary electrode pad PP142 extending in the second direction (y) is further provided. The second auxiliary electrode pad PP142 may be connected to the ends of the plurality of second auxiliary electrodes P142.

The first auxiliary electrode P141 and the first auxiliary electrode pad PP141 may be integrally formed of the same material, and the second auxiliary electrode P142 and the second auxiliary electrode pad PP142 may also be integrally formed of the same material. It can be formed of.

Here, the first auxiliary electrode P141 and the second auxiliary electrode pad PP142 may be spaced apart from each other, and the second auxiliary electrode P142 and the first auxiliary electrode pad PP141 may be spaced apart from each other.

Therefore, on the front surface of the insulating member 200, the first auxiliary electrode pad PP141 is formed at one end of the both ends of the first direction x in the second direction y, and the second auxiliary electrode pad at the other end ( PP142) may be formed in the second direction (y), respectively.

As described above, the solar cell according to the present invention is combined with only one insulating member 200 on one semiconductor substrate 110 to form one integrated individual device, thereby making the solar cell module manufacturing process easier. Even if the semiconductor substrate 110 included in any one solar cell is damaged or defective during the solar cell module manufacturing process, only the corresponding solar cell formed of one integrated individual element can be replaced, and the process yield can be further improved. have.

In addition, as described above, a solar cell formed of one integrated individual element can minimize thermal expansion stress applied to the semiconductor substrate 110 during a manufacturing process.

Here, when the area of the insulating member 200 is equal to or larger than the area of the semiconductor substrate 110, when connecting the solar cell and the solar cell to each other, an interconnector (IC) may be attached to the front surface of the insulating member 200. A sufficient area can be secured. To this end, the area of the insulating member 200 may be larger than the area of the semiconductor substrate 110 and may be 2 times or less.

The rear surface of the semiconductor substrate 110 and the front surface of the insulating member 200 are attached to each other, so that the first electrode C141 and the first auxiliary electrode P141 are connected to each other, and the second electrode C142 and the second The auxiliary electrodes P142 may be connected to each other.

Here, as shown in (c) of FIG. 5, the width of each of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 is the first auxiliary electrode pad PP141 and the second auxiliary electrode pad ( PP142), that is, it can be changed as it progresses in the second direction (y). As an example, as it progresses in the second direction (y), the width of the first auxiliary electrode pad PP141 may vary between WP1a and WP1b, and the width of the second auxiliary electrode pad PP142 may be between WP2a and WP2b. Can be changed.

Accordingly, as illustrated in FIG. 5C, in the portion having the maximum widths WP1a and WP2a, the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 is extended to the end of the insulating member 200. The first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may expose a portion of the insulating member 200 in a portion having minimum widths WP1b and WP2b.

At this time, the planar shape of each end of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may include a curved surface.

FIG. 6 is a view for explaining a state in which the semiconductor substrate 110 and the insulating member 200 shown in FIG. 5 are connected to each other, and FIG. 7A is a cross-sectional view of the line 7a-7a in FIG. 6, and FIG. 7B 6 shows a cross-section of the 7b-7b line in FIG. 6, and FIG. 7c shows a cross-section of the 7c-7c line in FIG. 6.

As illustrated in FIG. 6, one semiconductor substrate 110 may be completely overlapped with one insulating member 200 to form one solar cell individual device.

For example, as illustrated in FIG. 7A, the first electrode C141 formed on the rear surface of the semiconductor substrate 110 and the first auxiliary electrode P141 formed on the front surface of the insulating member 200 overlap each other, and the electrode It may be electrically connected to each other by a connecting material (ECA).

In addition, the second electrode C142 formed on the rear surface of the semiconductor substrate 110 and the second auxiliary electrode P142 formed on the front surface of the insulating member 200 also overlap each other and are electrically connected to each other by an electrode connecting material (ECA). Can.

In addition, an insulating layer IL may be filled in a space spaced apart from each other between the first electrode C141 and the second electrode C142, and the space between the first auxiliary electrode P141 and the second auxiliary electrode P142 may be filled. The insulating layer IL may be filled in the space.

In addition, as illustrated in FIG. 7B, an insulating layer IL may be filled in a space spaced between the second auxiliary electrode P142 and the first auxiliary electrode pad PP141, as shown in FIG. 7C. The insulating layer IL may also be filled in a space spaced between the first auxiliary electrode P141 and the second auxiliary electrode pad PP142.

In addition, as illustrated in FIG. 6, each of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 includes first regions PP141-S1 and PP142-S1 overlapping the semiconductor substrate 110. , The second regions PP141-S2 and PP142-S2 that do not overlap the semiconductor substrate 110.

As described above, the second region PP141-S2 of the first auxiliary electrode pad PP141 and the second region PP142 of the second auxiliary electrode pad PP142 provided to secure a space that can be connected to the interconnector IC An interconnector (IC) may be connected to -S2). Each of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 according to the present invention includes a second region PP141-S2, PP142-S2, so that the interconnector IC can be more easily connected. In addition, when connecting the interconnector (IC), it is possible to minimize the thermal expansion stress to the semiconductor substrate (110).

At this time, as shown in FIGS. 7B and 7C, the second region PP141-S2 of the first auxiliary electrode pad PP141 to which the interconnector IC is connected and the second of the second auxiliary electrode pad PP142 In the region PP142-S2, irregularities may be formed as described in FIG. 1B. Accordingly, it is possible to further enhance the adhesive strength with the interconnector (IC).

Here, the second regions PP141-S2 and PP142-S2 of each of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are in the first direction x along the second direction y. The width is not constant, and can be changed repeatedly from WPS1a to WPS1b or WPS2a to WPS2b.

So far, the first electrode C141 and the second electrode C142 formed on the semiconductor substrate 110 overlap in a direction parallel to the first auxiliary electrode P141 and the second auxiliary electrode P142 formed on the insulating member 200. However, the first electrode C141 and the second electrode C142 formed on the semiconductor substrate 110 are different from the first auxiliary electrode P141 and the second electrode formed on the insulating member 200. Even when overlapping and connecting in the direction intersecting the auxiliary electrode P142, the width of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 along the second direction y may be changed.

In addition, even if the first auxiliary electrode P141 and the second auxiliary electrode P142 are not formed in plural, and are formed of a single electrode, the first auxiliary electrode pad PP141 along the second direction (y) or The width of the second auxiliary electrode pad PP142 may be changed.

So far, the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 have been described as an example, but differently, the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are different. ) May be formed in plural.

8 is a view for explaining a second embodiment of the solar cell module according to the present invention, Figure 9 is a view for explaining the insulating member 200 of the solar cell applied to the solar cell module shown in Figure 8 to be.

In FIGS. 8 and 9, descriptions of the same contents as described in FIGS. 1 to 7C are omitted.

As shown in FIG. 8, in the solar cell module according to the present invention, the width at which the interconnector (IC) and the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142) are connected is the width of the interconnector (IC). Section that changes as it progresses in the longitudinal direction (y), but the connection width is not gradually increased or decreased, and the interconnector (IC) and the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142) are connected In the connection width may be constant as WC1 or WC2, in the remaining section, the interconnector IC and the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may not be connected.

At this time, the width of WC1 or WC2 may be the same or different from each other. At this time, the structure of the interconnector (IC) may be the same as described in FIG. 1.

The structure of the semiconductor substrate 110 may be the same as described in FIGS. 3 to 5 (a) and (b), but the first auxiliary electrode P141 or the second auxiliary electrode P142 formed on the insulating member 200 ) Is different from that described in FIG. 5( c ).

For example, the pattern of the first auxiliary electrode P141 or the second auxiliary electrode P142 formed on the insulating member 200 of the solar cell applied to the solar cell module illustrated in FIG. 8 may be the same as FIG. 9.

9, the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may each be formed in plural.

Here, a plurality of first auxiliary electrodes P141 are connected to each of the plurality of first auxiliary electrode pads PP141, and a plurality of second auxiliary electrodes P142 are also connected to each of the plurality of second auxiliary electrode pads PP142. Can.

Here, the plurality of first auxiliary electrode pads PP141 or the plurality of second auxiliary electrode pads PP142 may be arranged in the second direction y, and the plurality of first auxiliary electrode pads PP141 may be arranged in the second direction. They may be spaced apart from each other in (y), and the plurality of second auxiliary electrode pads PP142 may be spaced apart from each other in the second direction (y).

Accordingly, the end of the insulating member 200 is a portion (AOP) where a plurality of first auxiliary electrode pads (PP141) or a second auxiliary electrode pad (PP142) is formed, and a plurality of first auxiliary electrode pads (PP141) or The second auxiliary electrode pad PP142 is not formed, and may include an exposed portion ANP.

Here, widths WP1 and WP2 of the plurality of first auxiliary electrode pads PP141 or the second auxiliary electrode pads PP142 along the second direction y may be constant as illustrated in FIG. 9.

However, differently, the widths of the plurality of first auxiliary electrode pads PP141 or the second auxiliary electrode pads PP142 along the second direction y may be changed.

10 is a view for explaining an example different from the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 shown in FIG. 9.

As illustrated in FIG. 10, each of the first auxiliary electrode pads PP141 or the second auxiliary electrode pads PP142 included in the plurality of first auxiliary electrode pads PP141 or the second auxiliary electrode pads PP142 is The width in the first direction x along the second direction y may be changed.

Specifically, as shown in (a) and (b) of FIG. 10, each of the first auxiliary electrode pads PP141 included in the plurality of first auxiliary electrode pads PP141 or the second auxiliary electrode pads PP142 ) Or the second auxiliary electrode pad PP142 may include a curved surface.

Accordingly, as illustrated in FIG. 10A, each first auxiliary electrode pad PP141 or second auxiliary electrode pad PP142 has a center edge width WPb in the second direction (y). It may be smaller than the width (WBa) of the portion, or alternatively, as shown in FIG. 10(b), the edge width (WBa) may be formed to be larger than the width (WBb) of the central portion.

In addition, as shown in (c) of FIG. 10, each of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 linearly increases in width from the edge to the center portion, and The portion may be in a form in which the width is kept constant. Therefore, the width WPa of the central portion may be larger than the width WPa of the edge portion.

In addition to this, in the solar cell according to the present invention, each of the first auxiliary electrode pads PP141 or the second auxiliary electrode pads PP142 has various widths in the first direction x along the second direction y. It can have a changing form.

In this way, the width of each of the first auxiliary electrode pads PP141 or the second auxiliary electrode pads PP142 in the first direction x along the second direction y changes the interconnector IC. The width in which the interconnector IC is connected to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may be changed according to the second direction (y), which is the longitudinal direction (y) of.

Accordingly, when the interconnector (IC) is connected to each solar cell, a phenomenon in which the insulating member 200 is bent due to a difference in thermal expansion coefficient can be minimized. Therefore, the insulating member 200 is integrally connected to the solar cell. The phenomenon in which the semiconductor substrate 110 is damaged or damaged in a tabbing process in which the interconnector (IC) is connected can be minimized.

11 to 14 are views for explaining a third embodiment of the solar cell module according to the present invention.

Here, FIG. 11 is an example in which an interconnector (IC) having a different width along the length direction is applied to the solar cell module, FIG. 12 is an example of a solar cell applied to the solar cell module in FIG. 11, and FIG. FIG. 14 is a view for explaining the semiconductor substrate 110 and the insulating member 200 in another example solar cell that can be applied to the battery module, and FIG. 14 is a semiconductor substrate 110 and the insulating member 200 shown in FIG. 13. Is a diagram for explaining a state in which integral connections are made.

As illustrated in FIG. 11, in the solar cell module according to the present invention, the connection width between the interconnector IC and the first auxiliary electrode pad PP141 or the interconnector IC and the second auxiliary electrode pad PP142 is connected. In order to change as it progresses in the longitudinal direction (y) of the interconnector (IC), it is possible to use an interconnector (IC) whose width is not constant as it progresses in the longitudinal direction (y) of the interconnector (IC). .

That is, in the first position in the second direction y, the width of the interconnector IC may be greater than WIa, and in the second position, the width of the interconnector IC may be less than WIb than WIa. Therefore, in the first position, the distance between the interconnector (IC) and the semiconductor substrate 110 may be small as GSI1a or GSI2a, and in the second position, the distance between the interconnector (IC) and the semiconductor substrate 110 may be GSI1a or It may be larger than GSI2a as GSI1b or GSI2b.

The plane of the solar cell including the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may be as shown in FIG. 12 below.

As shown in FIG. 12, the solar cell applied to the third embodiment of the solar cell module is a semiconductor in which the first electrode C141 and the second electrode C142 are formed on the rear surface, as described in FIGS. 3 to 7C. The insulating member 200 on which the substrate 110, the first auxiliary electrode P141, the first auxiliary electrode pad PP141, and the second auxiliary electrode P142 and the second auxiliary electrode pad PP142 are formed on the front surface. An integrally connected solar cell can be used.

The structure of the solar cell illustrated in FIG. 12 is the same as that described in FIGS. 3 to 7C except for the width of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142, so a detailed description thereof will be omitted.

However, as illustrated in FIG. 12, the solar cell applied to the third embodiment of the solar cell module may include the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 as it progresses in the second direction (y). ) May have a constant width.

Therefore, as an example, as illustrated in FIG. 12, the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may be formed to the end of the insulating member 200, and the semiconductor substrate 110 may be formed. The widths WPS1 and WPS2 in the first direction x from the end to the end of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may be constant.

In addition, the solar cells illustrated in FIGS. 13 and 14 may be used in the solar cell module illustrated in FIG. 11.

Specifically, when the semiconductor substrate 110 is formed of only a single crystal silicon substrate, as illustrated in FIG. 13A, corner portions of the semiconductor substrate 110 may be formed in a diagonal direction. However, even in this case, the patterns of the first electrode C141 and the second electrode C142 may be the same as described in FIG. 5A.

However, in this case, in the insulating member 200, the pattern of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may be different. That is, a part of the pattern of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 is formed in the second direction (y) as described in FIG. 5A, but the first auxiliary electrode pad ( Among the patterns of PP141) or the second auxiliary electrode pad PP142, the portion overlapping the corner portion of the semiconductor substrate 110 formed by the diagonal line may be formed in the diagonal direction as the direction of the corner portion of the semiconductor substrate 110. have.

Here, the width (WP1a, WP2a) of the portion formed by the diagonal line of the pattern of the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142) is the width of the portion (WP1b, WP2b) formed in the second direction (y) It can be formed larger.

As described above, a portion formed by a diagonal line among the patterns of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may not be connected to the interconnector IC, and the first auxiliary electrode pad PP141 or the 2 In addition, the length of the auxiliary electrode pad PP142 is relatively smaller than the portion formed in the second direction y, and even if the interconnector IC is connected, the interconnector IC is connected because it is formed in a diagonal direction. At this time, the degree of bending of the insulating member 200 may be relatively weak.

Accordingly, the widths WP1b and WP2b of the portions formed in the second direction y are the widths WP1a and WP2a of the portions formed by diagonal lines among the patterns of the first auxiliary electrode pad PP141 or the second auxiliary electrode pads PP142. By making it larger, the sheet resistance at both ends of the pattern of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 can be further reduced.

As described above, when the semiconductor substrate 110 illustrated in FIG. 13 and the insulating member 200 are integrally connected, it may be as illustrated in FIG. 14.

As described above, when the semiconductor substrate 110 and the insulating member 200 are integrally connected, a portion of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 does not overlap with the semiconductor substrate 110. , Can be exposed out.

So far, the connection width between the solar cell module according to the present invention and the interconnector (IC) and the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142) is the longitudinal direction (y) of the interconnector (IC). In the case of change as proceeding to, only the cases of (1) and (2) described above in FIG. 1 were described, but as described in FIG. 1, how many of the cases of (1) and (2) are mixed and used Anything is possible. A detailed description thereof will be omitted.

In addition, as described above, an interconnector (IC) connecting a plurality of solar cell modules to each other may be formed in a structure for further improving adhesion, which will be described below.

Next, FIG. 15 is a view for explaining the overall cross-sectional structure of the solar cell modules according to the first to third embodiments.

15, the solar cell module according to the present invention, as described above, the first solar cell (Cell-a) and the second solar cell (Cell-b) in addition to the cell string connected to each other, the front glass A substrate, an upper encapsulant, a lower encapsulant, and a back sheet may be further included.

Here, each of the plurality of solar cells including the first solar cell (Cell-a) and the second solar cell (Cell-b) is connected to the above-described semiconductor substrate 110 and the insulating member 200, one by one, respectively. It is possible to form individual devices.

As illustrated in FIG. 15, the front glass substrate FG is formed on the front surface of a cell string in which the first solar cell (Cell-a) and the second solar cell (Cell-b) are connected to each other by an interconnector (IC). It can be located, the transmittance is high and can be made of tempered glass or the like to prevent damage. At this time, the tempered glass may be low iron tempered glass having a low iron content, and although not shown, an embossing treatment may be performed on the inner surface to increase light scattering effect.

The upper encapsulant EC1 may be located between the front glass substrate FG and the cell string, and the lower encapsulant EC2 may be located at the back of the cell string, that is, between the back sheet BS and the cell string. .

The upper encapsulant EC1 and the lower encapsulant EC2 may be formed of a material that prevents corrosion of metal due to moisture penetration and protects the solar cell module 100 from impact. For example, it may be formed of ethylene vinyl acetate (EVA, ethylene vinyl acetate).

As illustrated in FIG. 16, the upper encapsulant EC1 and the lower encapsulant EC2 are arranged with a plurality of solar cells during a lamination process while being disposed on the front and rear surfaces of the plurality of solar cells, respectively. Can be integrated.

In addition, the back sheet (BS) is located on the back of the lower encapsulation material (EC2) in the form of a sheet, it is possible to prevent moisture from entering the back of the solar module. The rear sheet (BS) may be made of an insulating material such as EP/PE/FP (fluoropolymer /polyeaster/ fluoropolymer).

The above description is merely illustrative of the technical spirit of the present invention, and those of ordinary skill in the art to which the present invention pertains can make various modifications, changes, and substitutions without departing from the essential characteristics of the present invention. will be. Therefore, the embodiments and the accompanying drawings disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments and the accompanying drawings. . The scope of protection of the present invention should be interpreted by the claims below, and all technical spirits within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

Claims (19)

A first solar cell and a second solar cell formed of one integrated individual element by connecting a semiconductor substrate having an electrode portion and an insulating member having an auxiliary electrode portion electrically connected to the electrode portion, respectively; And
An interconnector electrically connecting the first solar cell and the second solar cell in a first direction.
Including,
The electrode portion includes a plurality of first electrodes and a plurality of second electrodes extending in the first direction from a back surface of the semiconductor substrate,
The auxiliary electrode unit may include a first auxiliary electrode and a first auxiliary electrode pad connected to the plurality of first electrodes on a front surface of the insulating member, and a second auxiliary electrode and a second connected to the plurality of second electrodes. It includes an auxiliary electrode pad,
The interconnector is electrically connected to the first auxiliary electrode pad of the first solar cell and the second auxiliary electrode pad of the second solar cell, or the second auxiliary electrode pad of the first solar cell and the second sun Electrically connected to the first auxiliary electrode pad of the battery,
The connection width between the interconnector and the first auxiliary electrode pad or the interconnector and the second auxiliary electrode pad changes as it progresses in the longitudinal direction of the interconnector,
A solar cell module having irregularities formed on at least one of the bonding surfaces of the interconnector and the first and second auxiliary electrode pads. According to claim 1,
A solar cell module having irregularities formed on at least one of a portion of the interconnector connected to the first and second auxiliary electrode pads and a portion of the first and second auxiliary electrode pads connected to the interconnector. delete According to claim 1,
The connection width has a maximum connection width and a minimum connection width,
The maximum connection width and the minimum connection width are repeated as the solar cell module progresses in the longitudinal direction of the interconnector. According to claim 4,
In the portion having the minimum connection width, the interconnector is spaced apart from the first auxiliary electrode pad or the second auxiliary electrode pad without being connected. According to claim 1,
A solar cell module including a curved surface having a flat shape in which the interconnector and the first auxiliary electrode pad or the second auxiliary electrode pad are connected. According to claim 1,
The solar cell module
A front glass substrate positioned on the front surface of the cell string formed by electrically connecting the first solar cell and the second solar cell by the interconnector in the first direction;
An upper encapsulant positioned between the front glass substrate and the cell string;
A lower encapsulant located on the rear side of the cell string; And
A solar cell module further comprising; a rear sheet located on the rear side of the lower encapsulant. According to claim 1,
Each of the first auxiliary electrode and the second auxiliary electrode extends in the first direction,
The first auxiliary electrode pad is connected to an end of the first auxiliary electrode extending in the first direction, and extends in a second direction crossing the first direction,
The second auxiliary electrode pad is connected to an end of the second auxiliary electrode extending in the first direction, and extends in the second direction. The method of claim 8,
Each of the first auxiliary electrode pad and the second auxiliary electrode pad
The solar cell module having a constant width in the first direction as it progresses in the second direction. The method of claim 8,
A solar cell module includes ends of each of the first auxiliary electrode pad and the second auxiliary electrode pad. delete According to claim 1,
The width of the interconnector is a constant solar cell module as it progresses in a second direction crossing the first direction. According to claim 1,
The width of the interconnector is not constant as it progresses in a second direction crossing the first direction. delete delete delete delete delete delete

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