CN218525596U

CN218525596U - Back contact solar cell, roofing photovoltaic module and photovoltaic building

Info

Publication number: CN218525596U
Application number: CN202222372684.0U
Authority: CN
Inventors: 章康平; 王建明; 徐承宗; 刘骏; 舒华富; 刘勇
Original assignee: Das Solar Co Ltd
Current assignee: Yidao New Energy Technology Co ltd
Priority date: 2022-09-06
Filing date: 2022-09-06
Publication date: 2023-02-24
Anticipated expiration: 2032-09-06

Abstract

The embodiment of the application provides a back contact solar cell, a roof photovoltaic module and a photovoltaic building. The back contact solar cell comprises a back plate, wherein a first grid line and a second grid line are arranged on the back plate at intervals, and a conductive piece, a welding piece and a connecting piece are arranged on the first grid line; the conducting piece is connected with the first grid line, the welding piece is embedded in the conducting piece, the height of the welding piece is smaller than that of the conducting piece, the connecting piece is connected with the welding piece, and at least part of the connecting piece protrudes out of the welding piece and is used for connecting a welding strip. Because the connecting piece at least partially protrudes out of the welding piece, the connecting surface for connecting the welding strip is heightened through the connecting piece, and therefore the connecting piece is easily connected with the welding strip. The problem that the silver block is sunken in the aluminum block and is difficult to be welded with the solder strip after the back contact solar cell is subjected to a sintering process is solved.

Description

Back contact solar cell, roofing photovoltaic module and photovoltaic building

Technical Field

The application belongs to the technical field of photovoltaics, and particularly relates to a back contact solar cell, a roof photovoltaic assembly and a photovoltaic building.

Background

Solar energy has the advantages of no pollution, no regional limitation, inexhaustibility and the like, and the solar photovoltaic power generation technology becomes a main direction for developing and utilizing new energy. The anode and the cathode of the back contact solar cell are arranged on the back of the cell, so that shading is reduced, the energy conversion efficiency of the module is improved, and the application prospect is wide.

In the prior art, the back contact solar cell includes a P-type grid line and an N-type grid line, wherein the P-type grid line is provided with an aluminum block and a silver block, and the silver block is embedded in the aluminum block. After the back contact solar cell is subjected to a sintering process, the silver block is sunken in the aluminum block, namely the height of the silver block is lower than that of the aluminum block, so that the silver block embedded in the aluminum block is difficult to weld with the solder strip.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention has been made to provide a back contact solar cell, roofing photovoltaic module and photovoltaic building that overcomes or at least partially solves the above mentioned problems.

In order to solve the technical problem, the present application is implemented as follows:

in a first aspect, an embodiment of the present application provides a back contact solar cell, where the back contact solar cell includes a back plate, where a first gate line and a second gate line are arranged on the back plate at an interval, and a conductive piece, a solder piece, and a connecting piece are arranged on the first gate line;

the conducting piece is connected with the first grid line, the welding piece is embedded in the conducting piece, the height of the welding piece is smaller than that of the conducting piece, the connecting piece is connected with the welding piece, and at least part of the connecting piece protrudes out of the welding piece and is used for connecting a welding strip.

Optionally, the connecting member at least partially protrudes from or is flush with the conductive member.

Optionally, the conductive piece is provided with a groove, and the welding piece is embedded in the groove.

Optionally, the conductive piece is a conductive block, the welding piece is a welding block, the connecting piece is a connecting block, the welding block is embedded in the conductive block, and the connecting block is connected to the welding block and at least partially protrudes out of the welding block.

Optionally, the welding block is provided with a first connecting surface, the connecting block is provided with a second connecting surface, the first connecting surface is connected to the second connecting surface, and the first connecting surface and the second connecting surface are both planes.

Optionally, the number of the conductive blocks, the number of the welding blocks and the number of the connecting blocks are all multiple;

the plurality of conductive blocks are distributed on the first grid line at intervals, one welding block is correspondingly embedded in one conductive block, and one connecting block is correspondingly connected to one welding block.

Optionally, the number of the first gate lines and the number of the second gate lines are both multiple;

the first grid lines and the second grid lines are distributed on the backboard in an interlaced mode.

Optionally, the material of the connecting member includes one of tin and silver.

In a second aspect, the present application provides a roofing photovoltaic module, which includes the back contact solar cell.

In a third aspect, the embodiment of the present application provides a photovoltaic building, where the photovoltaic building includes the roofing photovoltaic module.

In the embodiment of the application, the back contact solar cell comprises a back plate, wherein a first grid line and a second grid line which are arranged at intervals are arranged on the back plate, and a conductive piece, a welding piece and a connecting piece are arranged on the first grid line; the conducting piece is connected with the first grid line, the welding piece is embedded in the conducting piece, the height of the welding piece is smaller than that of the conducting piece, the connecting piece is connected with the welding piece, and at least part of the connecting piece protrudes out of the welding piece and is used for connecting a welding strip. Because the connecting piece at least partially protrudes out of the welding piece, the connecting surface for connecting the welding strip is heightened through the connecting piece, and therefore the connecting piece is easy to realize the connection with the welding strip. The problem that the silver blocks are sunken in the aluminum blocks to be difficult to weld with the solder strips after the back contact solar cell is subjected to a sintering process is solved.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of a back contact solar cell according to an embodiment of the present disclosure;

fig. 2 is an isometric view of a back contact solar cell according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a back contact solar cell according to an embodiment of the present application, shown in a block diagram M in fig. 1.

Reference numerals: 10-a back plate; 20-a first gate line; 30-a second grid line; 21-a conductive member; 22-a weld; 23-a connector; 211-grooves; 24-a conductive block; 25-welding the blocks; 26-connecting blocks; 251-a first connection face; 261-second connection face.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present invention, and should not be construed as limiting the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The features of the terms first and second in the description and in the claims of the present application may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specified. In addition, "and/or" in the specification and claims means at least one of connected objects, a character "/" generally means that a preceding and succeeding related objects are in an "or" relationship.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship indicated based on the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Referring to fig. 1 to 3, there are shown schematic structural diagrams of a back contact solar cell according to an embodiment of the present application, which may specifically include: the back plate 10 is provided with a first grid line 20 and a second grid line 30 which are arranged at intervals on the back plate 10, and a conductive piece 21, a welding piece 22 and a connecting piece 23 are arranged on the first grid line 20;

the conductive element 21 is connected to the first gate line 20, the solder part 22 is embedded in the conductive element 21, the height of the solder part 22 is less than that of the conductive element 21, the connecting element 23 is connected to the solder part 22, and at least part of the connecting element 23 protrudes out of the solder part 22 for connecting a solder strip.

In the embodiment of the present application, since the connecting member 23 at least partially protrudes from the welding member 22, the connecting surface for connecting the welding strip is heightened by the connecting member 23, so that the connection with the welding strip is easily achieved by the connecting member 23. The problem that the silver block is sunken in the aluminum block and is difficult to be welded with the solder strip after the back contact solar cell is subjected to a sintering process is solved.

For example, in the embodiment of the present application, the Back Contact solar cell may include an Inter Back Contact (IBC) solar cell, in which positive and negative electrodes are arranged on one side of a backlight surface of the solar cell in an interdigital manner, and a P-N junction is located on a Back surface of the solar cell.

In particular, the IBC solar cell may include a P-type IBC and an N-type IBC. The P-type IBC refers to an IBC solar cell including a silicon wafer substrate of boron (element symbol is B) or gallium (element symbol is Ga), and the N-type IBC refers to an IBC solar cell including a silicon wafer substrate of phosphorus (element symbol is P).

In the embodiment of the present application, specifically, the back plate 10 may be a silicon plate. According to the crystal form of the silicon plate, the backplate 10 may be a polysilicon backplate 10, a single-crystal silicon backplate 10, or a non-polysilicon backplate 10, for example, and the specific type of the backplate 10 may not be limited in the embodiments of the present application.

For example, in the embodiment of the present application, the first gate line 20 may be a P-type gate line, and the second gate line 30 may be an N-type gate line. A plurality of second solder parts may be disposed on the second gate line 30, and the second solder parts are distributed on the second gate line 30 at intervals for connecting solder strips. Specifically, the second welding piece can adopt a silver block, and the second welding piece has high thermal conductivity and good weldability.

Optionally, in the present embodiment, the connecting member 23 at least partially protrudes from the conductive member 21 or is flush with the conductive member 21. In this way, in the case that the connecting member 23 is flush with the conductive member 21, the connecting member 23 can be directly connected to the solder strip, which facilitates the soldering of the solder strip to the connecting member 23. Under the condition that the connecting piece 23 at least partially protrudes out of the conductive piece 21, the connecting piece 23 is more convenient to be connected with the welding strip, the welding strip is welded on the connecting piece 23, the connection reliability between the connecting piece 23 and the welding strip is improved, and the welding processing is convenient to carry out.

In the embodiment of the present application, optionally, the conductive member 21 is provided with a groove 211, and the welding member 22 is embedded in the groove 211. By providing the groove 211 on the conductive member 21, the groove 211 is adapted to the welding member 22, that is, the two are the same in shape and the same or similar in size. So that the solder member 22 can be more firmly embedded on the conductive member 21.

Optionally, in the embodiment of the present application, the conductive component 21 is a conductive block 24, the welding component 22 is a welding block 25, the connecting component 23 is a connecting block 26, the welding block 25 is embedded in the conductive block 24, and the connecting block 26 is connected to the welding block 25 and at least partially protrudes from the welding block 25. The conductive member 21, the solder member 22, and the connecting member 23 are easily molded and easily obtained by forming the conductive member 21 as the conductive block 24, forming the solder member 22 as the solder block 25, and forming the connecting member 23 as the connecting block 26.

Specifically, in this embodiment, the material of the conductive block 24 may include aluminum, the conductive block 24 is set to an aluminum paste block, the aluminum paste is subjected to screen printing and rapid thermal treatment in a tunnel furnace, and then good ohmic contact can be achieved after sintering, so that the back plate 10 of the back contact solar cell forms an aluminum back field, thereby improving open-circuit voltage and improving photoelectric conversion efficiency of the back contact solar cell. The material of the solder bump 25 may include silver, which has high thermal conductivity and good solderability.

Optionally, in the embodiment of the present application, the welding block 25 has a first connecting surface 251, the connecting block 26 has a second connecting surface 261, the first connecting surface 251 is connected to the second connecting surface 261, and both the first connecting surface 251 and the second connecting surface 261 are planar. Thus, since the first connection surface 251 and the second connection surface 261 are both flat surfaces, the solder bump 25 and the connection bump 26 can have better connection effect, and the connection reliability between the two is improved.

In some optional embodiments of the present application, the number of the conductive bumps 24, the solder bumps 25, and the connection pads 26 is multiple, the conductive bumps 24 are distributed at intervals on the first gate line 20, one solder bump 25 is embedded in one conductive bump 24, and one connection pad 26 is connected to one solder bump 25. Like this, be convenient for all can realize the welding with a plurality of connecting block 26 welding the area, all can realize welding area and back contact solar cell's welding in a plurality of positions, improve the connection stability between the two.

Optionally, in this embodiment of the application, the number of the first gate lines 20 and the second gate lines 30 is multiple, and the multiple first gate lines 20 and the multiple second gate lines 30 are distributed on the backplane 10 in an staggered manner. Thus, a structure of the crossed back contact solar cell can be formed, and the photoelectric conversion efficiency of the solar cell can be improved.

Illustratively, in the embodiment of the present application, the material of the connecting member 23 includes one of tin and silver. The two materials have high thermal conductivity and good weldability, wherein tin is used as the connecting piece 23, so that the economic benefit is high, and the production cost of the back contact solar energy can be reduced.

In summary, the back contact solar cell according to the embodiment of the present application may include at least the following advantages:

in the embodiment of the application, the back contact solar cell comprises a back plate, wherein a first grid line and a second grid line which are arranged at intervals are arranged on the back plate, and a conductive piece, a welding piece and a connecting piece are arranged on the first grid line; the conducting piece is connected with the first grid line, the welding piece is embedded in the conducting piece, the height of the welding piece is smaller than that of the conducting piece, the connecting piece is connected with the welding piece, and at least part of the connecting piece protrudes out of the welding piece and is used for connecting a welding strip. Because the connecting piece at least partially protrudes out of the welding piece, the connecting surface for connecting the welding strip is heightened through the connecting piece, and therefore the connecting piece is easily connected with the welding strip. The problem that the silver block is sunken in the aluminum block and is difficult to be welded with the solder strip after the back contact solar cell is subjected to a sintering process is solved.

The embodiment of the application also provides a solar cell module, and the solar cell module comprises the back contact solar cell. Specifically, the solar cell module may further include glass (e.g., low-iron ultra-white textured tempered glass), an encapsulant (e.g., ethylene Vinyl Acetate Copolymer, EVA for short, or Polyolefin elastomer, POE for short), a functional back sheet, an interconnection bar, a bus bar, a junction box, and a frame (e.g., an aluminum alloy frame). The service life of the material can reach 15-25 years, and the material has wide application.

The solar cell module provided by the embodiment of the application can at least have the following advantages:

in the embodiment of the application, the solar cell module comprises the back contact solar cell. The back contact solar cell comprises a back plate, wherein a first grid line and a second grid line are arranged on the back plate at intervals, and a conductive piece, a welding piece and a connecting piece are arranged on the first grid line; the conducting piece is connected with the first grid line, the welding piece is embedded in the conducting piece, the height of the welding piece is smaller than that of the conducting piece, the connecting piece is connected with the welding piece, and at least part of the connecting piece protrudes out of the welding piece and is used for connecting a welding strip. Because the connecting piece at least partially protrudes out of the welding piece, the connecting surface for connecting the welding strip is heightened through the connecting piece, and therefore the connecting piece is easy to realize the connection with the welding strip. The problem that the silver blocks are sunken in the aluminum blocks to be difficult to weld with the solder strips after the back contact solar cell is subjected to a sintering process is solved.

The embodiment of the application also provides a roof photovoltaic module, which comprises the back contact solar cell.

The roofing photovoltaic module of this application embodiment can include the following advantage at least:

in the embodiment of the application, the roofing photovoltaic module comprises the back contact solar cell. The back contact solar cell comprises a back plate, wherein a first grid line and a second grid line are arranged on the back plate at intervals, and a conductive piece, a welding piece and a connecting piece are arranged on the first grid line; the conducting piece is connected with the first grid line, the welding piece is embedded in the conducting piece, the height of the welding piece is smaller than that of the conducting piece, the connecting piece is connected with the welding piece, and at least part of the connecting piece protrudes out of the welding piece and is used for connecting a welding strip. Because the connecting piece at least partially protrudes out of the welding piece, the connecting surface for connecting the welding strip is heightened through the connecting piece, and therefore the connecting piece is easily connected with the welding strip. The problem that the silver block is sunken in the aluminum block and is difficult to be welded with the solder strip after the back contact solar cell is subjected to a sintering process is solved.

The embodiment of the application also provides a photovoltaic building, which comprises the roof photovoltaic module.

in the embodiment of the application, the photovoltaic building comprises the roofing photovoltaic module, and the roofing photovoltaic module comprises the back contact solar cell. The back contact solar cell comprises a back plate, wherein a first grid line and a second grid line are arranged on the back plate at intervals, and a conductive piece, a welding piece and a connecting piece are arranged on the first grid line; the conducting piece is connected with the first grid line, the welding piece is embedded in the conducting piece, the height of the welding piece is smaller than that of the conducting piece, the connecting piece is connected with the welding piece, and at least part of the connecting piece protrudes out of the welding piece and is used for connecting a welding strip. Because the connecting piece at least partially protrudes out of the welding piece, the connecting surface for connecting the welding strip is heightened through the connecting piece, and therefore the connecting piece is easily connected with the welding strip. The problem that the silver block is sunken in the aluminum block and is difficult to be welded with the solder strip after the back contact solar cell is subjected to a sintering process is solved.

In the description of the present specification, reference to the description of "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A back contact solar cell is characterized by comprising a back plate, wherein a first grid line and a second grid line are arranged on the back plate at intervals, and a conductive piece, a welding piece and a connecting piece are arranged on the first grid line;

the conductive piece is connected to the first grid line, the welding piece is embedded in the conductive piece, the height of the welding piece is smaller than that of the conductive piece, the connecting piece is connected to the welding piece, and at least part of the connecting piece protrudes out of the welding piece and is used for connecting a welding strip.

2. The back contact solar cell of claim 1, wherein the connecting member at least partially protrudes from or is flush with the conductive member.

3. The back contact back junction solar cell of claim 1, wherein said conductive member has a groove, and said solder member is embedded in said groove.

4. The back contact solar cell of claim 1, wherein the conductive member is a conductive block, the solder member is a solder block, and the connecting member is a connecting block, the solder block is embedded in the conductive block, and the connecting block is connected to the solder block and at least partially protrudes from the solder block.

5. The back contact back junction solar cell of claim 4, wherein the solder bump has a first connection face, the solder bump has a second connection face, the first connection face is connected to the second connection face, and the first connection face and the second connection face are both planar.

6. The back contact solar cell of claim 4, wherein the number of the conductive block, the soldering block and the connecting block is plural;

7. The back contact solar cell of claim 1, wherein the first grid lines and the second grid lines are each multiple in number;

the first grid lines and the second grid lines are distributed on the back plate in an staggered mode.

8. The back contact back junction solar cell of claim 1, wherein the material of the connecting member comprises one of tin and silver.

9. A roofing photovoltaic assembly, comprising the back contact solar cell of any one of claims 1-8.

10. A photovoltaic building comprising the roofing photovoltaic assembly of claim 9.