KR102371947B1 - CELL DIVISION/INTERCONNECTION STRUCTURE SOLAR MODULE USING ELECTRODE PATTERN WITH LESS Ag - Google Patents

Abstract

The present application provides a tile-stacked photovoltaic module including two or more solar cells, wherein the solar cells have finger electrodes arranged parallel to an upper surface, a finger auxiliary line vertically connecting the finger electrodes, and a rear surface disposed on the lower surface Including an electrode, the solar cells are superimposedly connected by a conductive adhesive layer interposed between the upper and lower rear electrode of the finger auxiliary line, it relates to a tile-laminated solar module.

Description

Cell division/junction structure solar module using Ag reduction electrode pattern {CELL DIVISION/INTERCONNECTION STRUCTURE SOLAR MODULE USING ELECTRODE PATTERN WITH LESS Ag}

The present application relates to a tiled laminated structure solar module and a method for manufacturing the same.

A solar cell means generating electrical energy when light is irradiated on a substrate. Unlike thermal power generation or nuclear power generation, solar cells do not emit harmful substances such as harmful gases and radioactive waste during power generation.

The structure of the solar cell includes a substrate and an emitter made of semiconductors of different conductive types, such as p-type and n-type, and an electrode connected to the substrate and the emitter, respectively. Since the and emitter have different conductivity types, a pn junction is formed.

When light is incident on such a solar cell, a plurality of electron-hole pairs are generated in the semiconductor, and the generated electron-hole pairs are separated into electrons and holes that are charged by the photovoltaic effect, so that electrons and holes are n-type of the semiconductor and the p-type semiconductor, for example, in the emitter and substrate direction, are collected by electrodes electrically connected to the substrate and emitter, and power can be obtained by connecting these electrodes with wires.

Since the power generated from one solar cell is small, a module in which a plurality of solar cells are connected in series and parallel is usually used for solar power generation. The existing module manufacturing method is a method of manufacturing cells by connecting cells with a plurality of metal ribbons, and it requires space to prevent electrical short circuit of cells, and output loss occurs due to busbars, so solar modules compared to cells Methods for reducing the efficiency loss (cell-to-module loss or CTM loss) are being studied.

Photovoltaic modules are being manufactured in various ways, such as first dividing a cell and then connecting the divided cell with other divided cells by soldering the front bus bar to the front bus bar of the divided cell. However, in the solar tube module manufactured in this way, stress and microcracks may occur due to local heat transfer and pressure generated during the soldering process. suggests a way to do it.

Korea Patent Publication No. 10-1874016, which is the background technology of the present application, relates to a high-efficiency PERC solar cell having a shingled array structure and a method for manufacturing the same. The high-efficiency PERC solar cell having a shingled array structure of the above registered patent only includes an electrode serving as a bus bar, and does not include a bus bar and electrode pad on the front and rear surfaces or an electrode performing the same role. It is not recognized about the laminated structure solar module.

The present application is intended to solve the problems of the prior art described above, and an object of the present application is to provide a tiled laminated structure solar module.

In addition, an object of the present application is to provide a method of manufacturing the tile-stacked solar module.

However, the technical overlayer to be achieved by the embodiment of the present application is not limited to the technical problems as described above, and other technical problems may exist.

As a technical means for achieving the above technical problem, the first aspect of the present application is a tile-stacked photovoltaic module including two or more solar cells, wherein the photovoltaic cells are finger electrodes arranged parallel to the upper surface, a finger auxiliary line vertically connecting the finger electrode and a rear electrode disposed on a lower surface, wherein the solar cells are superimposedly connected by a conductive adhesive layer interposed between the upper side of the auxiliary finger line and the lower rear electrode Provided is a photovoltaic module with a phosphorus, tile and laminate structure.

According to one embodiment of the present application, the solar cell includes a light absorption layer formed on the rear electrode, an emitter formed on the light absorption layer, a passivation layer formed on the emitter, and a finger electrode formed on the emitter. It may include, but is not limited to.

According to one embodiment of the present application, the solar cell may not include an electrode pad on the rear surface and a bus electrode on the upper surface, but is not limited thereto.

According to one embodiment of the present application, the light absorption layer is single crystal polysilicon, polycrystalline polysilicon, group III-V compound, group II-VI compound, group I-III-VI compound, perovskite, quantum dots, and their It may include a material selected from the group consisting of combinations, but is not limited thereto.

According to the exemplary embodiment of the present application, the rear electrode, the finger electrode, and the auxiliary finger line are each independently Ag, Al, Au, Pt, Ti, Ni, Zr, Ta, Zn, Nb, Cr, Co, Mn , Fe, Al, Mg, Si, W, Cu, lanthanide metals, nitrides thereof, oxides thereof, and may include a material selected from the group consisting of combinations thereof, but is not limited thereto.

According to one embodiment of the present application, the conductive adhesive layer is Ag, Ni, C, Ti, acrylic rubber or polystyrene coated with a metal selected from Au, Ag, Ni, C, Ti, Au and combinations thereof. may include, but is not limited thereto.

According to the exemplary embodiment of the present application, the solar module may further include a metal wire for connecting the solar cells, but is not limited thereto.

According to one embodiment of the present application, the passivation layer is SiN _x :H, Si ₃ N ₄ , SiO _x , SiON, Al ₂ O ₃ , SiC, MgF ₂ , ZnS, TiO ₂ , CeO ₂ , and combinations thereof It may include a material selected from the group consisting of, but is not limited thereto.

In addition, the second aspect of the present application is a solar cell including a finger electrode arranged parallel to the upper surface and a rear electrode arranged on the lower surface in a method for manufacturing a tile-laminated solar module in a direction perpendicular to the finger electrode forming a conductive adhesive on a finger auxiliary line connecting the cut surface of the finger electrode of the divided solar cell on one side, and the conductive adhesive on a part of the rear electrode of the divided solar cell on the other side It provides a method of manufacturing a tile-laminated solar module comprising the step of bonding the solar cell of the one side and the solar cell of the other side by attaching an adhesive.

According to the exemplary embodiment of the present application, the method may further include, but is not limited to, forming a finger auxiliary line connecting the cut surface of the finger electrode of the divided solar cell on one side.

According to the exemplary embodiment of the present application, the step of dividing the solar cell may be performed by a laser method, a mechanical scribing method, a sawing method, and a method selected from the group consisting of combinations thereof, but is not limited thereto.

According to one embodiment of the present application, the forming of the conductive adhesive includes screen printing, bar coating, spin coating, nozzle printing, spray coating, slot die coating, gravure printing, inkjet printing, electrohydrodynamic jet printing (electrohydrodynamic jet printing). ), electrospray, and a method selected from the group consisting of combinations thereof, but is not limited thereto.

According to one embodiment of the present application, after bonding the divided solar cells, forming a metal wire on the solar module and passivating the solar module may be further included, but is limited thereto it is not

The above-described problem solving means are merely exemplary, and should not be construed as limiting the present application. In addition to the exemplary embodiments described above, additional embodiments may exist in the drawings and detailed description.

Since the power generated from one solar cell is small, it is usually manufactured in the form of a module in which a plurality of solar cells are connected in series and parallel. The existing module manufacturing method is a method of manufacturing a cell by connecting the cell with a plurality of metal wires, and it requires space to prevent electrical short circuit of the cells, and an output loss occurs due to the bus bar. Methods for reducing efficiency loss (cell-to-module loss or CTM loss) are being studied.

According to the above-described problem solving means of the present application, since the photovoltaic efficiency is maintained without including the front bus bar and the rear electrode pad in the tiled laminated structure solar module according to the present application, the conventional cell division / junction structure of the solar module Compared to the manufacturing method, the use of Ag is reduced in manufacturing the front bus bar and the rear electrode pad, and as a result, the manufacturing cost can be reduced.

In addition, since the conventional solar cell module connects the bus bar on one side of the solar cell to the other side of the other solar cell by soldering, the efficiency of the solar cell such as current loss due to soldering and stress due to heat is reduced. Although it may be lowered, the solar cell efficiency can be increased because the tile-laminated solar module according to the present application uses a conductive adhesive.

In addition, since there is no bus bar other than the finger electrode on the light receiving surface of the tile-stacked solar module according to the present application, the light loss due to light reflection is reduced, and thus the power generation efficiency can also be increased.

However, the effects obtainable herein are not limited to the above-described effects, and other effects may exist.

1 is a schematic diagram of a solar cell according to an embodiment of the present application.
Figure 2 is a schematic front view of the tiled laminated structure solar module according to an embodiment of the present application.
Figure 3 is a schematic rear view of the tiled laminated structure solar module according to an embodiment of the present application.
4 is a schematic diagram of a tiled laminated structure solar module according to an embodiment of the present application.
5 is a schematic diagram of a conventional solar cell.
6 is a schematic front view of a conventional solar module.
7 is a schematic rear view of a conventional solar module.
Fig. 8 (a) is a schematic diagram of a conventional solar module, (b) and (c) are schematic diagrams showing a method of connecting a solar module.
9 is a flowchart of a method of manufacturing a tiled laminated structure solar module according to an embodiment of the present application.
10 is a schematic diagram of a method of forming a conductive adhesive layer according to an embodiment of the present application.
11 is a diagram illustrating a method of manufacturing a tiled laminated structure solar module according to an embodiment of the present application.
12 (a) is a photo of a tiled laminated structure solar module according to an embodiment of the present application, and (b) is a photo of a conventional shingled solar module according to a comparative example of the present application. a) is an image of a solar module according to an embodiment of the present application, and (b) is an image of a solar module according to a comparative example.
14 is a current-voltage graph of a solar module according to an embodiment and a comparative example of the present application.

Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement them.

However, the present application may be implemented in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present application in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout this specification, when a part is "connected" with another part, this includes not only the case where it is "directly connected" but also the case where it is "electrically connected" with another element interposed therebetween. do.

Throughout this specification, when it is said that a member is positioned “on”, “on”, “on”, “under”, “under”, or “under” another member, this means that a member is positioned on the other member. It includes not only the case where they are in contact, but also the case where another member exists between two members.

Throughout this specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.

As used herein, the terms "about," "substantially," and the like are used in a sense at or close to the numerical value when the manufacturing and material tolerances inherent in the stated meaning are presented, and to aid in the understanding of the present application. It is used to prevent an unconscionable infringer from using the mentioned disclosure in an unreasonable way. Also, throughout this specification, "step to" or "step for" does not mean "step for".

Throughout this specification, the term "combination of these" included in the expression of the Markush form means one or more mixtures or combinations selected from the group consisting of the components described in the expression of the Markush form, and the components It is meant to include one or more selected from the group consisting of.

Throughout this specification, reference to “A and/or B” means “A or B, or A and B”.

Hereinafter, with respect to the photovoltaic module and the manufacturing method of the laminated structure of the tile of the present application, it will be described in detail with reference to embodiments and examples and drawings. However, the present application is not limited to these embodiments and examples and drawings.

As a technical means for achieving the above technical problem, the first aspect of the present application is a tile-stacked photovoltaic module 10 including two or more solar cells 100 , wherein the solar cells 100 are a finger electrode 200 arranged parallel to the upper surface, a finger auxiliary line 300 vertically connecting the finger electrode 200, and a rear electrode 1000 disposed on the lower surface, the solar cell 100 They provide a tiled laminated structure solar module 10 that is superimposedly connected by a conductive adhesive layer 400 interposed between the upper and lower rear lower electrodes 1000 of the finger auxiliary line 300 .

1 is a schematic diagram of a solar cell 100 according to an embodiment of the present application.

According to the exemplary embodiment of the present application, the solar cell 100 includes a light absorption layer 3000 formed on the rear electrode 1000 , an emitter 4000 formed on the light absorption layer 3000 , and the emitter The passivation layer 5000 formed on the 4000 and the finger electrode 200 formed on the emitter 4000 may be included, but the present invention is not limited thereto. Hereinafter, a description of the structure of the solar cell 100 is with reference to FIG. 1 .

According to one embodiment of the present application, the solar cell 100 may further include a passivation layer 2000 and a local electric field layer 2100 between the rear electrode 1000 and the light absorption layer 3000, However, the present invention is not limited thereto.

The light absorption layer 3000 according to the present application refers to a region in which electrons and holes are produced by receiving sunlight.

According to one embodiment of the present application, the light absorption layer 3000 is a single crystal polysilicon, polycrystalline polysilicon, group III-V compound, group II-VI compound, group I-III-VI compound, perovskite, quantum dots, and a material selected from the group consisting of combinations thereof, but is not limited thereto.

The passivation layers 2000 and 5000 according to the present disclosure refer to anti-reflection layers, and serve to inhibit light irradiated to the solar cell from being reflected and emitted to the outside of the solar cell.

In this regard, the passivation layer 5000 positioned at the upper end of the emitter 4000 and the passivation layer 2000 positioned at the upper end of the rear electrode 1000 may perform the same role.

According to one embodiment of the present application, the passivation layer (2000, 5000) is SiN _x :H, Si ₃ N ₄ , SiO _x , SiON, Al ₂ O ₃ , SiC, MgF ₂ , ZnS, TiO ₂ , CeO ₂ , and a material selected from the group consisting of combinations thereof, but is not limited thereto.

The emitter 4000 according to the present disclosure is for forming a p-n junction for electron and hole pair separation, and may have a doping type different from that of the light absorption layer 3000 . For example, when the light absorption layer 3000 is a p-type silicon substrate, the emitter 4000 may be an n-type silicon substrate.

The local electric field layer 2100 according to the present disclosure is formed on the upper end of the rear electrode 1000 , and refers to an electric field formed by a voltage applied to the rear electrode 1000 . The local electric field layer 2100 is to improve the efficiency of the solar cell 100 by suppressing recombination of electrons in the solar cell 100 .

The solar cell 100 included on the tile-stacked photovoltaic module 10 may have the same structure as a conventional solar cell. For example, the solar cell 100 and the conventional solar cell may have a structure as shown in FIG. 1 .

When light is irradiated to a conventional solar cell, electrons and holes generated in the light absorption layer 3000 move through the rear electrode 1000 and the emitter 4000 to produce electrical energy. According to previous research, a module was devised in which a plurality of conventional solar cells were connected by attaching a metal ribbon to the front and rear portions of the conventional solar cell to increase the efficiency of the conventional solar module, but the module is There is a problem in that the area receiving light by the metal ribbon is reduced.

In order to overcome the problem of reducing the power generation area of the module, a method of splitting a conventional solar cell and bonding it with a conductive adhesive rather than a metal ribbon has been proposed. However, when a conventional solar cell is connected through the conductive adhesive, a large amount of expensive material such as silver (Ag) is required as a material, resulting in an increase in manufacturing cost.

The present invention may have a similarity to a conventional solar module of a cell division/junction structure in that the divided solar cells 100 are connected using the conductive adhesive, but the tiled and laminated structure solar module 10 ) does not include the bus electrode and the back electrode pad. Accordingly, the present application can provide a tiled laminated structure solar module 10 that is manufactured at a lower cost than a conventional process.

According to one embodiment of the present application, the solar cell 100 may not include an electrode pad on the rear surface and a bus electrode on the upper surface, but is not limited thereto.

The bus electrode included in the conventional solar module means an electrode for connecting the finger electrode 200 and the finger electrode 200 . As will be described later, electrical energy generated in a conventional solar cell by the bus electrode may be transferred to another solar cell through the finger electrodes 200, but the area at the bottom of the bus electrode can produce electrical energy. There are no downsides.

In addition, the rear electrode pad of the conventional solar module may mean a region in which a metal ribbon for connecting the bus electrode is formed or a region in which a conductive adhesive is formed to contact the bus electrode. The metal ribbon or the conductive adhesive is formed on the top of the bus electrode on the upper surface of the conventional solar cell and attached to the electrode pad at the bottom of another solar cell, thereby connecting a plurality of conventional solar cells.

The tile-stacked photovoltaic module 10 according to the present application can transmit current only with the conductive adhesive layer 400 without the electrode pad and the bus electrode on the rear side.

2 is a schematic front view of the solar module 10 of the tile-stacked structure according to an embodiment of the present application, and FIG. is a schematic diagram of a tiled laminated structure solar module 10 according to an embodiment of the present application.

According to the exemplary embodiment of the present application, the tiled laminated structure solar module 10 may include a finger electrode 200 and a finger auxiliary line 300 vertically connecting the finger electrode 200, but is limited thereto. it's not going to be

The finger electrode 200 according to the present application is also referred to as a grid line, and is formed on the passivation layers 2000 and 5000 to collect the current generated by the light absorption layer 3000 and the emitter 4000 .

According to the exemplary embodiment of the present application, the finger electrodes 200 may be disposed on one side of the solar cell 100 at regular intervals in the longitudinal direction or the width direction of the solar cell 100 . , but is not limited thereto.

The finger auxiliary line 300 according to the present disclosure refers to a wire for connecting the finger electrode 200 and the finger electrode 200 .

In the photovoltaic module 10 having a tile-stack structure, at least one finger electrode 200 not in contact with the conductive adhesive layer 400 may be present. In this regard, the finger auxiliary line 300 connects the plurality of finger electrodes 200 so that all the finger electrodes 200 come into contact with the conductive adhesive layer 400 to allow current to flow. can do.

Therefore, even if the finger auxiliary line 300 is not present, the tile-stacked photovoltaic module 10 can produce power, and the finger auxiliary line 300 is the power production efficiency of the tiled-laminated photovoltaic module 10 . to further improve

According to one embodiment of the present application, the rear electrode 1000, the finger electrode 200, and the auxiliary finger line 300 are each independently Ag, Al, Au, Pt, Ti, Ni, Zr, Ta, It may include a material selected from the group consisting of Zn, Nb, Cr, Co, Mn, Fe, Al, Mg, Si, W, Cu, lanthanide metals, nitrides thereof, oxides thereof, and combinations thereof. , but is not limited thereto.

According to one embodiment of the present application, the tile-stacked photovoltaic module 10 is perpendicular to the finger electrode 200 formed on one side of the photovoltaic cell 100 in the photovoltaic cell 100 . After division in one direction, the divided solar cell 100 may include a structure in which the divided solar cells 100 are bonded using the conductive adhesive, but is not limited thereto.

2 to 4, electrons and holes generated in the light absorption layer 3000 are transferred to other solar cells through the finger electrode 200, the finger auxiliary line 300, and the conductive adhesive layer 400 ( 100), and the tiled laminated structure solar module 10 according to the present application does not include a bus electrode, a rear electrode pad, and a metal ribbon for electrically connecting the rear electrode pad and the bus electrode. can be checked

The photovoltaic module 10 having a tiled laminate structure according to the present application can produce electrical energy only through the conductive adhesive layer 400, the finger electrode 200, and the finger auxiliary line 300, so that the manufacturing cost is low. do.

In the case of the tile-stacked solar module 10 according to the present application, since both-side light-receiving type (bi-facial) power generation is possible, the tile-stacked solar module 10 has the electrode structure of FIGS. 2 and 3, specifically As a result, the finger electrode 200 and the rear electrode 1000 may be included at the same time, and light may be generated from the front and rear surfaces, resulting in high efficiency.

For example, the solar cell may form an Ag reduction electrode structure, and accordingly, the finger electrode 200 and the auxiliary line 300 of the finger electrode 200 are included on one side of the solar cell, A rear electrode 1000 may be included on the other side of the solar cell, but is not limited thereto.

The conductive adhesive layer 400 according to the present application is for connecting at least two or more of the solar cells 100 , and means an adhesive layer capable of transmitting electricity, unlike a general adhesive layer. Herein, the term "electrical conductive adhesive layer 400" may be used interchangeably with an electrically conductive adhesive.

The conductive adhesive layer 400 is for electronic packaging, and unlike soldering, it can be processed at a low temperature, is environmentally friendly because it does not use toxic substances, has a simple process, and has various advantages such as wide application. there is.

According to an exemplary embodiment of the present application, the conductive adhesive layer 400 used in the solar module 10 having a tiled and laminated structure may include an anisotropic conductive adhesive or an anisotropic conductive adhesive, but is not limited thereto.

The conductive adhesive according to the present invention may include an isotropic conductive adhesive in which current can flow in all directions, an anisotropic conductive adhesive in which current can flow in only one direction, and the like. An anisotropic conductive adhesive may be used to control the current generated in the solar cell 100 to flow in only one direction, such as an up-down direction, a left-right direction, and a front-back direction.

According to one embodiment of the present application, the conductive adhesive layer 400 is Ag, Ni, C, Ti, acrylic rubber coated with a metal selected from Au, Ag, Ni, C, Ti, Au, and combinations thereof. ) or polystyrene, but is not limited thereto.

In this regard, when bonding the plurality of solar cells 100 to manufacture the tile-laminated solar module 10 , the conductive adhesive is excessively applied to one side of the solar cell 100 . And/or if the other side is printed, an electrical short may occur. In order to overcome this problem, the conductive adhesive layer 400 may be applied at a predetermined interval from the corner portion of the other side of the solar cell 100 .

However, when the conductive adhesive is applied at a predetermined distance from the corner portion of the other side of the solar cell 100, a portion of the finger electrode 200 in contact with the corner portion does not come into contact with the conductive adhesive. There may be a problem that current cannot be collected. As described above, the problem can be solved by the finger auxiliary line 300 .

According to the exemplary embodiment of the present application, the path through which current flows in the tile-stacked solar module 10 is the finger electrode 200, the finger auxiliary line 300, and the conductive adhesive layer on one side of the solar cell. 400 , and a rear electrode 1000 of the solar cell, but is not limited thereto.

According to the exemplary embodiment of the present application, the tile-stacked photovoltaic module 10 may further include a metal wire (not shown) for connecting the solar cells 100 , but is not limited thereto.

The metal wiring (not shown) according to the present application is for connecting the solar cells 100 connected by the conductive adhesive layer 400 .

5 is a schematic diagram of a conventional solar cell, FIGS. 6 and 7 are front and rear schematic diagrams of a conventional solar module, (a) of FIG. 8 is a schematic diagram of a conventional solar module, (b) and (c) is a schematic diagram showing a method of connecting a solar module.

4 to 8 , the conductive adhesive layer 400 of the photovoltaic module 10 with the rear electrode pad and the bus electrode included in the conventional photovoltaic module and the tile-stacked structure is each of the solar cells It serves to transfer the electrical energy generated in ( 100 ) to another solar cell ( 100 ). However, as described above, since the back electrode pad and the bus electrode contain an expensive material, for example, silver (Ag), mass production is difficult, and in the light absorption layer 3000 located at the bottom of the bus electrode, electron and There is a disadvantage in that no holes are generated.

On the other hand, since the tiled laminated structure solar module 10 of the present application does not include a metal ribbon, an electrode pad, and a bus electrode, as described above, less expensive materials than a conventional solar module, for example, silver (Ag) It can be manufactured using

In addition, the second aspect of the present application is a solar cell including a finger electrode 200 arranged parallel to the upper surface and a rear electrode 1000 arranged on the lower surface in the method of manufacturing the tiled laminated structure solar module 10 . Splitting (100) in a direction perpendicular to the finger electrode 200, on the auxiliary finger line 300 connecting the cut surface of the finger electrode 200 of the divided solar cell 100 on one side Forming a conductive adhesive, and attaching the conductive adhesive to a part of the rear electrode 1000 of the divided solar cell 100 on the other side to the solar cell 100 on the one side and the solar cell on the other side It provides a method of manufacturing a tile-laminated solar module (10), comprising the step of bonding (100).

With respect to the manufacturing method of the solar module 10 of the tile-stack structure according to the second aspect of the present application, detailed description of the overlapping parts with the first aspect of the present application is omitted, but even if the description is omitted, the first aspect of the present application The contents described in can be equally applied to the second aspect of the present application

9 is a flowchart of a method of manufacturing a tiled laminated structure solar module 10 according to an embodiment of the present application.

Unlike the conventional cell division / junction structure solar module, the solar module 10 of the present application does not include a bus electrode and a back electrode pad, so the method of manufacturing the solar module 10 of the tile-stack structure Since it does not include the process of forming the bus electrode and the process of forming the rear electrode pad, the manufacturing step may be simple.

In order to manufacture the tile-stacked solar module 10 according to the present application, a solar cell 100 including a finger electrode 200 arranged parallel to the upper surface and a rear electrode 1000 arranged on the lower surface is applied to the finger It is divided in a direction perpendicular to the electrode 200 (S100).

According to one embodiment of the present application, the step of dividing the solar cell 100 in a direction perpendicular to the finger electrode 200 includes the finger electrode 200 of the divided solar cell 100 on one side. The step of forming the auxiliary finger line 300 connecting the cut surfaces may be further included, but the present invention is not limited thereto.

Since the conventional photovoltaic module includes a bus electrode, when the finger electrode 200 is disposed in a horizontal direction, for example, when the finger electrode 200 is disposed in an up-down direction, the conventional photovoltaic module is vertically The solar cell 100 divided in the direction was included.

However, since the solar cell 100 of the present application does not include a bus electrode, the finger electrode 200 may be disposed in a direction perpendicular to the finger electrode 200, for example, in the vertical direction. In this case, the solar module according to the present application includes the solar cell 100 divided in the left and right directions.

According to one embodiment of the present application, the step of dividing the solar cell 100 may be performed by a laser method, a mechanical scribing method, a sawing method, and selected from the group consisting of combinations thereof, but is limited thereto it is not

Next, a conductive adhesive is formed on the auxiliary finger line 300 connecting the cut surface of the finger electrode 200 of the divided one side of the solar cell 100 ( S200 ).

The region in which the conductive adhesive is formed may refer to the conductive adhesive layer 400 .

According to one embodiment of the present application, the conductive adhesive layer 400 is to be formed in an open state in some regions of the passivation layers 2000 and 5000 of the solar cell 100 or the divided solar cell 100 . However, the present invention is not limited thereto.

According to one embodiment of the present application, the step of opening the passivation layer 2000, 5000 is a process comprising a lithography (lithography), chemical etching, dry etching, photolithography, and a process comprising one selected from the group consisting of combinations thereof. may be performed, but is not limited thereto.

10 is a schematic diagram of a method of forming a conductive adhesive layer 400 according to an embodiment of the present application.

Referring to FIG. 10 , the conductive adhesive layer 400 (ECA) may be formed on the emitter 4000 exposed by partially opening the passivation layers 2000 and 5000 . In this regard, the solar cell 100 on which the conductive adhesive layer 400 is formed may be coupled to the rear electrode 1000 of another solar cell 100, and by the coupling, a tile-laminated solar module (10) can be formed.

According to one embodiment of the present application, the forming of the conductive adhesive includes screen printing, bar coating, spin coating, nozzle printing, spray coating, slot die coating, gravure printing, inkjet printing, electrohydrodynamic jet printing (electrohydrodynamic jet printing). ), electrospray, and a method selected from the group consisting of combinations thereof, but is not limited thereto.

Next, the conductive adhesive layer 400 is formed on a part of the rear electrode 1000 of the divided solar cell 100 on the other side to form the solar cell 100 on the one side and the solar cell 100 on the other side. to join (S300).

According to the exemplary embodiment of the present application, after the conductive adhesive layer 400 is formed on the solar cell 100 , the solar cell 100 may be divided and joined, but is not limited thereto.

For example, after placing one side of the divided solar cell 100 printed with the conductive adhesive to overlap and contact the rear electrode 1000 of the other divided solar cell 100, the By curing the conductive adhesive, the divided solar cells 100 may be bonded.

According to one embodiment of the present application, after bonding the divided solar cell 100 , forming a metal wiring on the solar module 10 and passivating the solar module 10 . may further include, but is not limited thereto.

Passivating the photovoltaic module 10 blocks the loss of electrons and holes generated in the tile-stacked photovoltaic module 10, and reflects the light reflected from the light absorption layer 3000 to reflect the sunlight This may be performed to increase the power generation efficiency of the module 10 .

The present invention will be described in more detail through the following examples, but the following examples are for illustrative purposes only and are not intended to limit the scope of the present application.

[Example]

11 is a diagram illustrating a method of manufacturing a tiled laminated structure solar module according to an embodiment of the present application.

A solar cell having a silver (Ag) reduction electrode structure was manufactured. Then, the solar cell was divided into a plurality of cells with respect to a direction perpendicular to the finger electrode formed on the solar cell. Then, a conductive adhesive was applied on the divided solar cells, and the divided solar cells were joined, and then connected with a metal wire.

[Comparative example]

By cutting the back side of a commercial solar cell with a laser, 4 to 6 solar cells were manufactured.

Then, a conductive adhesive (ECA) was applied to the front bus bar of the cell, and the ECA was bonded to the rear Ag pad of another cell to fabricate a single string. At this time, a sufficient amount of ECA was used so that the bus bar and the Ag pad were not exposed to the outside.

Then, the strings were connected in series and parallel structure, and they were electrically connected by soldering them with a metal ribbon to prepare a solar cell having a tile-stacked structure (busing process). The solar cells of the tiled and laminated structure were arranged according to the designed module structure, and a cover glass, an EVA film, and a back sheet were laminated on the solar cell to prepare a solar cell module sealed from the external environment. Then, a junction box for transmitting electricity produced by the module to the outside and a frame for securing rigidity and fastening properties were combined.

Fig. 12 (a) is a photograph of a tile-stacked solar module according to the embodiment, and (b) is a photograph of a conventional shingled solar module according to the comparative example.

Referring to FIG. 12 , the shingled solar module has a bus bar, unlike the tile-stacked solar module. Therefore, the tile-stacked solar module can reduce manufacturing cost by using less silver (Ag) compared to the conventional shingled solar module.

[Experimental Example 1]

13 (a) is an image of a solar module according to the embodiment, (b) is an image of a solar module according to a comparative example, and FIG. 14 is a current of a solar module according to the embodiment and comparative example -It is a voltage graph.

Referring to FIG. 13 , it can be confirmed that (a) does not have a bus bar, (b) shows that there is a bus bar, and the power generation performance of the modules of the Examples and Comparative Examples is shown in Table 1 below.

Example
((a) of FIG. 13) comparative example
((b) of FIG. 13) Size [cm ² ] 235.05 235.05 I _sc [A] 1.855 1.855 J _SC [mA/cm ² ] 7.895 7.893 V _OC [V] 3.348 3.342 FF [%] 78.84 78.78 Eff [%] 20.84 20.78 P _m [W] 4.899 4.885

Referring to Table 1 and FIG. 14 , it can be confirmed that the photovoltaic module without busbars (Example) can have similar efficiency while using less material than the photovoltaic module with busbars (Comparative Example).

The above description of the present application is for illustration, and those of ordinary skill in the art to which the present application pertains will understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present application. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a dispersed form, and likewise components described as distributed may also be implemented in a combined form.

The scope of the present application is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present application.

10: tiled laminated structure solar module
100: solar cell
110: corner of the solar cell
200: finger electrode
300: finger auxiliary line
400: conductive adhesive layer
1000: back electrode
2000: passivation layer
2100: local full layer
3000: light absorption layer
4000 : emitter
5000: passivation layer

Claims (13)

In the tiled laminated structure solar module comprising two or more solar cells,
The solar cell includes finger electrodes arranged parallel to an upper surface, a finger auxiliary line vertically connecting the finger electrodes, a rear electrode disposed on a lower surface, a light absorption layer formed on the rear electrode, and an emitter formed on the light absorption layer and a passivation layer formed on the emitter,
The solar cells are superimposedly connected by a conductive adhesive layer interposed between the upper and lower rear lower electrodes of the auxiliary finger lines,
The tiled laminated structure solar module includes a metal wiring for connecting the divided solar cells,
The solar cell does not include an electrode pad on the back and a bus electrode on the top,
The finger electrode is formed on the emitter,
The tiled laminated structure solar module is capable of double-sided light-receiving type power generation,
The finger auxiliary line connects a plurality of finger electrodes,
The conductive adhesive layer includes an anisotropic conductive adhesive, and is applied at regular intervals from the corner portion of the other side of the solar cell,
at least one finger electrode not in contact with the conductive adhesive layer is in contact with the conductive adhesive layer by the finger auxiliary line;
Electrons and holes generated in the light absorption layer are transferred to other solar cells through the finger electrode, the finger auxiliary line, and the conductive adhesive layer,
A path through which current flows in the tile-stacked solar module includes the finger electrode on one side of the solar cell, the finger auxiliary line, the conductive adhesive layer, and a rear electrode of the solar cell,
The light absorption layer is p-type silicon,
The emitter is n-type silicon,
The rear electrode, the finger electrode, and the finger auxiliary line include Ag,
The conductive adhesive layer is to include Ag coated with Au,
The conductive adhesive bonds the solar cells by curing,
Wherein the passivation layer comprises SiN _x :H,
Tiled laminated structure solar module.
delete delete delete delete delete delete delete delete delete delete delete delete

Images