阅读说明：本技术 叠瓦组件及其制造方法 (Laminated tile assembly and manufacturing method thereof ) 是由 尹丙伟 孙俊 陈登运 李岩 石刚 于 2020-12-01 设计创作，主要内容包括：本发明涉及一种叠瓦组件及其制造方法。叠瓦组件包括：至少一个电池串,每一个电池串包括位于末端处的连接片,连接片的底表面上具有第一导电结构和第二导电结构,第一导电结构与和该连接片相邻的太阳能电池片的正电极导电接触,第二导电结构和第二汇流条导电接触。第一汇流条与每一个电池串的首端的太阳能电池片的底表面上的导电结构导电接触。本发明能够实现叠瓦组件的正极汇流条和负极汇流条均连接在电池串的底表面上,以使得叠瓦组件的顶表面上无法看到汇流条,这样的设置既能够提升美观性,又避免了汇流条影响电池串的受光面积、降低叠瓦组件的工艺复杂度。(The invention relates to a laminated tile assembly and a manufacturing method thereof. The shingle assembly comprises: at least one cell string, each cell string including a tab at a terminal end, the tab having a first conductive structure on a bottom surface in conductive contact with a positive electrode of a solar cell adjacent the tab and a second conductive structure in conductive contact with a second bus bar. The first bus bar is in conductive contact with the conductive structure on the bottom surface of the solar cell sheet at the head end of each cell string. According to the invention, the positive bus bar and the negative bus bar of the laminated assembly are connected to the bottom surface of the battery string, so that the bus bars cannot be seen on the top surface of the laminated assembly, and the arrangement can not only improve the aesthetic property, but also avoid the influence of the bus bars on the light receiving area of the battery string and reduce the process complexity of the laminated assembly.)

1. A shingle assembly, comprising:

at least one cell string, each cell string comprising a plurality of solar cells arranged sequentially in a shingled manner in a first direction and a tab at an end of the cell string, wherein:

each solar cell is provided with a positive electrode and a back electrode, wherein any two adjacent solar cells comprise a first solar cell closer to the head end of the cell string and a second solar cell closer to the tail end of the cell string, and the positive electrode of the first solar cell and the back electrode of the second solar cell are in contact with each other to realize conductive connection;

the bottom surface of the connecting sheet is provided with a first conductive structure and a second conductive structure, and the first conductive structure is configured to be in conductive contact with the positive electrode of the solar cell sheet adjacent to the connecting sheet;

a first bus bar located at the head ends of all the cell strings and extending in a second direction perpendicular to the first direction, the first bus bar being configured to be in conductive contact with the conductive structure on the bottom surface of the solar cell sheet at the head end of each cell string;

a second bus bar located at an end of all of the cell strings and extending in a second direction, the second bus bar being configured to be in conductive contact with the second conductive structure of each tab.

2. The shingle assembly of claim 1, wherein each tab is a non-solar cell of photovoltaic character selected from at least one of a silicon wafer without a PN junction or a conductive material other than a silicon wafer.

3. The shingle assembly according to claim 1, wherein the second conductive structure of each connection tab is a conductive layer disposed on a bottom surface of the connection tab.

4. A stack assembly according to claim 1, wherein each connecting tab comprises a conductive layer disposed on a bottom surface thereof, and the second conductive structure is one or more conductive connections disposed on the bottom surface of the conductive layer.

5. The laminated tile assembly of claim 4, wherein the conductive connecting portion of each connecting sheet is plural, and the plural conductive connecting portions are arranged along an extending direction of the bus bar.

6. The shingle assembly of claim 1, wherein the first conductive structure of each tab is a conductive layer or a back electrode disposed on a bottom surface of the tab.

7. The shingle assembly of claim 1, wherein the first conductive structure and the second conductive structure of each connection tab are monolithic conductive layers that completely overlie the bottom surface of the base sheet.

8. The shingle assembly of claim 1, wherein the bottom surface of the connecting tab has a conductive layer disposed thereon, the conductive layer being one of a back electric field layer, an aluminum grid layer laminate, a silver grid layer laminate, and a silver aluminum grid layer laminate.

9. The shingle assembly of claim 1, wherein the tab is provided with a top surface film layer that completely covers the top surface thereof, the top surface film layer being a color that corresponds to the color of the top surface of the solar cell sheet.

10. The stack assembly of claim 9, wherein the top surface film layer of the connecting tab comprises a light transmissive conductive film and/or a passivation antireflective film.

11. The stack assembly of claim 1, wherein the bond pad includes a bus bar disposed on a top surface and/or a bottom surface of the bond pad.

12. The shingle assembly of claim 1, wherein each tab has a dimension in the first direction that is less than a dimension of the solar cell sheet in the first direction, and wherein each tab has a dimension in the second direction that is equal to a dimension of the solar cell sheet in the second direction.

13. The shingle assembly of claim 1, wherein the exposed top surface of each connecting tab has a dimension in the first direction equal to the dimension of the bus bar in the first direction.

14. The shingle assembly of claim 1, wherein the conductive structure on the bottom surface of the solar cell sheet at the head end of each cell string comprises at least one of a back electrode, a subgrid, a back field, a conductive connection.

15. The shingle assembly of claim 1, wherein the first bus bar and the second bus bar are secured to the cell string by a weld, conductive adhesive, or non-conductive adhesive.

16. The shingle assembly of claim 1, wherein the secondary bus bar is secured to the connector tab by a plurality of adhesive strips.

17. A method of manufacturing a stack assembly according to any one of claims 1-16, the method of manufacturing comprising:

a step of manufacturing a solar cell sheet;

a step of manufacturing a connecting piece, the step of manufacturing the connecting piece including:

providing a sheet of connecting pieces;

providing a first conductive structure and a second conductive structure on a bottom surface of a sheet of a connection pad;

arranging the solar cells and the connecting sheets into a cell string in a shingled manner, so that the connecting sheets are positioned at the tail ends of the cell string, and the first conductive structures of the connecting sheets are in conductive contact with the positive electrodes of the solar cells adjacent to the connecting sheets;

arranging a first bus bar to enable the first bus bar to be in conductive contact with the conductive structure on the bottom surface of the solar cell sheet at the head end of each cell string;

the second bus bar is arranged such that the second bus bar is in conductive contact with the second conductive structure of each connecting tab.

18. The method of claim 17, wherein the step of fabricating a connection pad further comprises the step of providing a light-transmissive conductive layer and/or a passivating antireflective film on the top surface of the silicon wafer.

19. The method of claim 17, wherein the step of fabricating the connecting tab does not include the step of providing a PN junction.

Technical Field

The invention relates to the field of energy, in particular to a laminated tile assembly and a manufacturing method thereof.

Background

With the increasing consumption of conventional fossil energy such as global coal, oil, natural gas and the like, the ecological environment is continuously deteriorated, and particularly, the sustainable development of the human society is seriously threatened due to the increasingly severe global climate change caused by the emission of greenhouse gases. Various countries in the world make respective energy development strategies to deal with the limitation of conventional fossil energy resources and the environmental problems caused by development and utilization. Solar energy has become one of the most important renewable energy sources by virtue of the characteristics of reliability, safety, universality, long service life, environmental protection and resource sufficiency, and is expected to become a main pillar of global power supply in the future.

In a new energy revolution process, the photovoltaic industry in China has grown into a strategic emerging industry with international competitive advantages. However, the development of the photovoltaic industry still faces many problems and challenges, and the conversion efficiency and reliability are the biggest technical obstacles restricting the development of the photovoltaic industry, while the cost control and the scale-up are economically restricted. The photovoltaic module is taken as a core component of photovoltaic power generation, and the development of high-efficiency modules by improving the conversion efficiency of the photovoltaic module is a necessary trend. Various high efficiency modules, such as shingles, half-sheets, multi-master grids, double-sided modules, etc., are currently emerging on the market. With the application places and application areas of the photovoltaic module becoming more and more extensive, the reliability requirement of the photovoltaic module becomes higher and higher, and particularly, the photovoltaic module with high efficiency and high reliability needs to be adopted in some severe or extreme weather frequent areas.

Under the background of vigorous popularization and use of green solar energy, the shingled assembly utilizes the electrical principle of low current and low loss (the power loss of the photovoltaic assembly is in direct proportion to the square of working current) so as to greatly reduce the power loss of the assembly. The tiling technology cuts the whole solar cell into small patterns again through special pattern design, and then bonds a plurality of adjacent cells or cells with better consistency of efficiency, appearance and the like together by using conductive adhesive, thereby manufacturing the assembly.

In the current industry, great attention is paid to improving the appearance performance of the laminated assembly and simplifying the manufacturing process of the short lead, and the aspects of thermal expansion coefficients of connecting sheets, welding strips, laminated solar cells and the like need to be considered in the process. The existing laminated tile technology has some defects, for example, the existing conventional laminated tile battery piece adopts solar battery end lead welding, the manufacturing process is complex, and the end lead welding strip can be obviously seen on the front surface of the component.

There is thus a need to provide a stack assembly and a method of manufacturing the same that at least partially solves the above problems.

Disclosure of Invention

The invention aims to provide a laminated tile assembly and a manufacturing method thereof. According to the tile-stacked assembly provided by the invention, the connecting sheet is arranged at the tail end of each battery string, so that the positive bus bar and the negative bus bar of the tile-stacked assembly can be connected to the bottom surface of the battery string, and the bus bars cannot be seen on the top surface of the tile-stacked assembly.

Further, the tab may be made of the same substrate as a conventional solar cell, and such a tab does not affect the thermal expansion coefficient of other solar cells. The connecting sheet can be a false sheet without a PN junction, a process similar to that of the solar cell can be adopted when the connecting sheet is manufactured, and meanwhile, unnecessary process steps are reduced, so that the manufacturing cost of the connecting sheet is lower.

According to an aspect of the present invention, there is provided a stack assembly comprising:

at least one cell string, each cell string comprising a plurality of solar cells arranged sequentially in a shingled manner in a first direction and a tab at an end of the cell string, wherein:

each solar cell is provided with a positive electrode and a back electrode, wherein any two adjacent solar cells comprise a first solar cell closer to the head end of the cell string and a second solar cell closer to the tail end of the cell string, and the positive electrode of the first solar cell and the back electrode of the second solar cell are in contact with each other to realize conductive connection;

the bottom surface of the connecting sheet is provided with a first conductive structure and a second conductive structure, the first conductive structure is configured to be in conductive contact with the positive electrode of the solar cell sheet adjacent to the connecting sheet, and the area of the connecting sheet is smaller than that of the solar cell sheet;

a first bus bar located at the head ends of all the cell strings and extending in a second direction perpendicular to the first direction, the first bus bar being configured to be in conductive contact with the conductive structure on the bottom surface of the solar cell sheet at the head end of each cell string;

a second bus bar located at an end of all of the cell strings and extending in a second direction, the second bus bar being configured to be in conductive contact with the second conductive structure of each tab.

In one embodiment, each tab is a non-solar cell of photovoltaic character selected from at least one of a silicon wafer without a PN junction or a conductive material other than a silicon wafer.

In one embodiment, the second conductive structure of each bond pad includes a conductive layer disposed on a bottom surface of the bond pad.

In one embodiment, each of the bond pads includes a conductive layer disposed on a bottom surface thereof, and the second conductive structure includes one or more conductive connections disposed on the bottom surface of the conductive layer.

In one embodiment, the conductive connecting portion of each connecting piece is plural, and the plural conductive connecting portions are arranged along the extending direction of the bus bar.

In one embodiment, the first conductive structure of each bond pad is a conductive layer or back electrode disposed on a bottom surface of the bond pad.

In one embodiment, the first conductive structure and the second conductive structure of each of the connection pads are monolithic conductive layers that completely cover the bottom surface of the substrate pad.

In one embodiment, a conductive layer is disposed on the bottom surface of the connection pad, and the conductive layer is one of a back electric field layer, an aluminum gate line layered structure, a silver gate line layered structure, and a silver-aluminum gate line layered structure.

In one embodiment, the tab is provided with a top surface film layer that completely covers the top surface thereof, and the color of the top surface film layer is consistent with the color of the top surface of the solar cell sheet.

In one embodiment, the top surface film layer of the connecting sheet comprises a light-transmitting conductive film and/or a passivation antireflection film.

In one embodiment, the bond pad further comprises a bus bar disposed on a top surface and/or a bottom surface of the bond pad.

In one embodiment, the dimension of each tab in the first direction is smaller than the dimension of the solar cell piece in the first direction, and the dimension of each tab in the second direction is equal to the dimension of the solar cell piece in the second direction.

In one embodiment, a dimension of the top surface of each connecting piece exposed outside in the first direction is equal to a dimension of the bus bar in the first direction.

In one embodiment, the conductive structure on the bottom surface of the solar cell sheet at the head end of each cell string includes at least one of a back electrode, a sub-grid line, a back electric field, and a conductive connection.

In one embodiment, the first bus bar and the second bus bar are fixed to the cell string by welding, conductive glue, or non-conductive adhesive.

In one embodiment, the second bus bar is fixed to the connection piece by a plurality of adhesive strips.

According to another aspect of the present invention there is provided a method of manufacturing a laminated assembly according to any one of the above aspects, the method of manufacturing comprising:

a step of manufacturing a solar cell sheet;

a step of manufacturing a connecting piece, the step of manufacturing the connecting piece including:

providing a sheet of connecting pieces;

providing a first conductive structure and a second conductive structure on a bottom surface of a sheet of a connection pad;

arranging the solar cells and the connecting sheets into a cell string in a shingled manner, so that the connecting sheets are positioned at the tail ends of the cell string, and the first conductive structures of the connecting sheets are in conductive contact with the positive electrodes of the solar cells adjacent to the connecting sheets;

arranging a first bus bar to enable the first bus bar to be in conductive contact with the conductive structure on the bottom surface of the solar cell sheet at the head end of each cell string;

the second bus bar is arranged such that the second bus bar is in conductive contact with the second conductive structure of each connecting tab.

In one embodiment, the step of fabricating the connection pad further comprises the step of providing a light transmissive conductive layer and/or a passivating antireflective film on the top surface of the silicon wafer.

In one embodiment, the step of fabricating the connecting pad does not include the step of providing a PN junction.

Drawings

For a better understanding of the above and other objects, features, advantages and functions of the present invention, reference should be made to the preferred embodiments illustrated in the accompanying drawings. Like reference numerals in the drawings refer to like parts. It will be appreciated by persons skilled in the art that the drawings are intended to illustrate preferred embodiments of the invention without any limiting effect on the scope of the invention, and that the various components in the drawings are not drawn to scale.

FIG. 1 is a schematic bottom surface view of a stack assembly according to a preferred embodiment of the present invention;

FIG. 2 is an enlarged view of a cross-sectional view taken along line A-A in FIG. 1;

FIG. 3 is an enlarged view of a cross-sectional view taken along line B-B in FIG. 1;

FIGS. 4-6 are views of several alternatives to FIG. 3;

figure 7 is a schematic bottom surface view of a connecting piece portion of a stack assembly according to another preferred embodiment of the present invention.

Reference numerals:

shingle assembly 100

First bus bar 1

Second bus bars 2, 21, 22, 23, 24

Battery string 3

Solar cells 31, 41, 51, 61

First solar cell 31a

Second solar cell 31b

Positive electrodes 311, 411, 511, 611

Cell back electrode 312

Cell conductive connection 313

Connecting pieces 32, 42, 52, 62, 72

Top surface film layer 321, 421, 521, 621

Conductive layers 322, 422, 522, 622, 722

Connecting sheet conductive connection portions 323, 523, 623

Connecting the tab back electrodes 524, 624

Adhesive tape 8

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings. What has been described herein is merely a preferred embodiment in accordance with the present invention and other ways of practicing the invention will occur to those skilled in the art and are within the scope of the invention.

The present invention provides a stack of tiles and a method of manufacturing the same, figures 1-7 showing some preferred embodiments according to the present invention. First, it should be noted that the "first direction" mentioned herein is the arrangement direction of the solar cells in the cell string, and is shown by D1 in fig. 1-6; the "second direction" referred to herein is an extending direction of the first bus bar and the second bus bar, and is shown by D2 in fig. 1; d3 in the drawing shows a direction perpendicular to both the first direction D1 and the second direction D2, wherein D3+ shows an upward direction when the stack is placed in an operative position on a horizontal plane and D3-shows a downward direction when the stack is placed in an operative position on a horizontal plane.

Referring first to fig. 1, a stack 100 includes at least one cell string 3, and in this embodiment stack 100 includes three cell strings 3. Each cell string 3 includes a plurality of solar cells 31 arranged in sequence in a shingled manner in the first direction D1 and a tab 32 located at an end of the cell string 3. The laminated tile assembly 100 further includes a first bus bar 1 disposed at a head end of each battery string 3 and a second bus bar 2 disposed at a tail end of each battery string 3, the first bus bar 1 and the second bus bar 2 each extending in the second direction D2 and each being disposed on a bottom surface of each battery string 3.

Referring to fig. 2, a positive electrode 311 and a back electrode may be disposed on each solar cell 31. In order to distinguish the back electrode on the solar cell 31 from the back electrode that may be present on the tab, the back electrode on the solar cell 31 is referred to herein as a cell back electrode 312. For convenience of description, any two adjacent solar cells 31 are referred to as a first solar cell 31a and a second solar cell 31b, respectively, and the first solar cell 31a is closer to the head end of the string 3 than the second solar cell 31b, and the second solar cell 31b is closer to the tail end of the string 3 than the first solar cell 31 a. Then, as shown in fig. 2, the positive electrode 311 of the first solar cell 31a and the cell back electrode 312 of the second solar cell 31b are in contact with each other to achieve conductive connection. The first solar cell 31a shown in fig. 2 is the solar cell 31 at the head end of the cell string 3 where the first solar cell 31a is located, and a cell conductive connection portion 313 (as an example of a conductive structure on the bottom surface of the solar cell 31) is provided on the bottom surface of the first solar cell 31a, and the cell conductive connection portion 313 is in conductive contact with the first bus bar 1. In other embodiments, not shown, the conductive structure on the bottom surface of the solar cell sheet at the head end of the cell string may also be the grid lines (minor grid lines and/or back electrodes) of the solar cell sheet, or the conductive structure on the bottom surface of the solar cell sheet may also include both grid lines and cell sheet conductive connection portions.

A cross-sectional view of the connecting tab 32 is shown in fig. 3. The tab 32 may be an optically non-solar cell, for example, the tab 32 may be a silicon wafer with no PN junction fabricated, or at least one of other conductive structures than a silicon wafer with no PN junction fabricated. The connecting pad 32 may be provided on a bottom surface thereof with a conductive layer 322 completely covering the bottom surface thereof, the connecting pad conductive connection portion 323 is provided on the bottom surface of the conductive layer 322, and the conductive layer 322 is one of a back electric field layer, an aluminum gate line layered structure, a silver gate line layered structure, and a silver-aluminum gate line layered structure. Preferably, the top surface of the base sheet of the connection sheet 32 is provided with a top surface film layer 321 completely covering the base sheet, and the color of the top surface film layer 321 is consistent with the color of the top surface of the solar cell sheet 31. For example, the top surface film layer 321 includes a light-transmitting conductive film and/or a passivation antireflection film. In other embodiments not shown, the bond pad 32 also includes a bus bar disposed on a top surface of the bond pad 32.

The tab 32 has, on a bottom surface thereof, a first conductive structure configured to be in conductive contact with the positive electrode 311 of the solar cell 31 adjacent to the tab 32, and a second conductive structure configured to be in conductive contact with the second bus bar 2. In the embodiment shown in fig. 3, the first conductive structure may be, for example, a conductive layer 322, and the second conductive structure may be, for example, a connecting pad conductive connection 323. The connecting piece 32 and the bus bar are fixed together by a conductive adhesive or a non-conductive adhesive (not shown).

Turning back to fig. 1, preferably, the cell conductive connection portion 313 may be a plurality of rectangular or other shaped dot structures disposed on the bottom surface of the solar cell 31 at the head end of the cell string 3 and arranged in sequence along the second direction D2, and the tab conductive connection portion 323 may be a plurality of rectangular or other shaped dot structures disposed on the bottom surface of the tab 32 and arranged in sequence along the second direction D2. The dimensions of the cell conductive connection portion 313 and the connecting-sheet conductive connection portion 323 in the first direction D1 may be slightly larger than the dimensions of the first and second bus bars 1 and 2 in the first direction D1. Such an arrangement may allow some error in applying the bus bars, as long as it is ensured that the first bus bars 1 are covered on the bottom surface of the respective cell sheet conductive connection portions 313 and the second bus bars 2 are covered on the bottom surface of the respective connecting sheet conductive connection portions 323, without applying the bus bars to the cell string 3 with high positional accuracy. Alternatively, the dimensions of the cell conductive connecting portion 313 and the connecting-piece conductive connecting portion 323 in the first direction D1 may be equal to or smaller than the dimensions of the first and second bus bars 1, 2 in the first direction D1. Preferably, the dimensions of the first and second bus bars 1, 2 in the first direction D1 are less than 6mm, preferably less than 0.2mm, for example 0.1 mm.

With continued reference to fig. 1, the dimension of the tab 32 in the second direction D2 is equal to the dimension of the solar cell 31 in the second direction D2, and the dimension of the tab 32 in the first direction D1 is smaller than the dimension of the solar cell 31 in the first direction D1, so that the area of the tab 32 is smaller than the area of the solar cell 31. Preferably, the dimension W2 of the top surface of each connecting tab 32 exposed outside in the first direction D1 may be equal to the dimension of the bus bar in the first direction D1. This arrangement can reduce the entire area of the connecting sheet 32 and avoid wasting the light receiving area of the entire laminated assembly 100. As can also be seen from fig. 1, a dimension W1 of the exposed top surface of each solar cell 31 in the first direction D1 is greater than a dimension W2 of the exposed top surface of the connecting sheet 32 in the first direction D1.

The first and second conductive structures on the bottom surface of the bond pad can have other arrangements in addition to the embodiment shown in fig. 3, and fig. 4-6 show several bond pads having other first and second conductive structures.

In the embodiment shown in fig. 4, the top surface of the connecting pad 42 is provided with a top surface film 421, the bottom surface is provided with a conductive layer 422, and the first conductive structure and the second conductive structure of the connecting pad 42 are both complete conductive layers 422 covering the bottom surface of the connecting pad 42. The second bus bar 21 is directly connected to the conductive layer 422 of the tab 42, and the positive electrode 411 of the solar cell 41 adjacent to the tab is also directly connected to the conductive layer 422 of the tab 42.

In the embodiment shown in fig. 5, the top surface of the tab 52 is provided with a top surface film layer 521, the bottom surface is provided with a conductive layer 522, the bottom surface of the conductive layer 522 is further provided with a tab conductive connection 523 and a back electrode at one side edge near the head end of the cell string, and in order to distinguish the back electrode of the tab 52 from the back electrode of the solar cell, the back electrode of the tab 52 is referred to herein as a tab back electrode 524. In the present embodiment, the first conductive structure is the connecting-pad back electrode 524 of the connecting pad 52, and the second conductive structure is the connecting-pad conductive connection portion 523. The positive electrode 512 and the tab back electrode 524 of the solar cell 51 adjacent to the tab 52 are in conductive contact, and the second bus bar 22 and the tab conductive connection portion 523 are in conductive contact.

In the embodiment shown in fig. 6, the top surface of the tab 62 is provided with a top surface film layer 621, the bottom surface is provided with a conductive layer 622, and the bottom surface of the conductive layer 622 is further provided with a tab back electrode 624 near one side edge of the head end of the cell string. In this embodiment, the first conductive structure is a tab back electrode 624 and the second conductive structure is a conductive layer 622. The positive electrode 611 and the tab back electrode 624 of the solar cell 61 adjacent to the tab 62 are in conductive contact, and the second bus bar 23 and the conductive layer 622 are in conductive contact.

Figure 7 shows a schematic bottom surface view of a connecting piece portion of a stack assembly according to another preferred embodiment of the present invention. In fig. 7, a conductive layer 722 is provided on the bottom surface of the connection tab 24, and a second bus bar 24 is provided on the bottom surface of the connection tab 24 to be conductively connected to the conductive layer 722. Also, in the embodiment shown in fig. 7, the connecting piece 72 and the second bus bar 24 are fixed together by the adhesive tape 8.

In the embodiment shown in fig. 7, an adhesive may also be provided between the connecting piece 72 and the second bus bar 24. Alternatively, in the embodiment shown in fig. 7, no adhesive is provided between the connecting piece 72 and the second bus bar 24, and the two are fixed together only by the adhesive tape 8. Also, the connecting tab 72 shown in fig. 7 may be configured in other configurations such as those shown in fig. 3-6. For example, a tab conductive connection may also be provided between the tab 72 and the second bus bar 24.

In combination with the above embodiments, it can be seen that the connection sheet is disposed at the end of each cell string, so that the positive bus bar and the negative bus bar of the stack assembly can be connected to the bottom surface of the cell string, and the bus bars cannot be seen on the top surface of the stack assembly. Moreover, the connecting sheet can be made of the same base material as that of the conventional solar cell, and the connecting sheet does not influence the thermal expansion coefficient of other solar cells. The connecting sheet can be a false sheet without a PN junction, a process similar to that of the solar cell can be adopted when the connecting sheet is manufactured, and meanwhile, unnecessary process steps are reduced, so that the manufacturing cost of the connecting sheet is lower.

The present invention also provides a method of manufacturing a laminated assembly, which may include a step of manufacturing a solar cell sheet, a step of manufacturing a tab sheet, a step of providing a first bus bar, and a step of providing a second bus bar. Compared with the steps of manufacturing the solar cell, the steps of manufacturing the PN junction on the silicon wafer are reduced in the steps of manufacturing the connecting sheet. Specifically, the step of providing the connecting piece includes: providing a sheet of connecting pieces, which may be, for example, a silicon wafer; first and second conductive structures are disposed on a bottom surface of the sheet of the bond pad. The method further comprises the following steps: arranging the solar cells and the connecting sheets into cell strings in a tiling mode, enabling the connecting sheets to be located at the tail ends of the cell strings, and enabling the first bus bars of the finally manufactured tiling assembly to be in conductive contact with the conductive structures on the bottom surfaces of the solar cells at the head ends of the cell strings; the second bus bar is brought into electrically conductive contact with the second conductive structure of each connection pad.

The conductive structure on the bottom surface of the solar cell sheet at the head end of the cell string may include at least one of a back electrode, a sub-grid line, a back electric field, and a conductive connection part. The first conductive structure on the bottom surface of the connection pad may be a conductive layer or a back electrode; the second conductive structure on the bottom surface of the tab can be a conductive layer or a conductive connection.

Preferably, when the sheet of the connecting piece is a silicon wafer, the step of manufacturing the connecting piece further comprises the step of texturing the surface of the silicon wafer; the step of manufacturing the connecting sheet further comprises the step of arranging a light-transmitting conductive layer and/or a passivation antireflection film on the top surface of the silicon wafer; the step of fabricating the bond pads may or may not also include the step of coating the bottom surface of the silicon die.

In order to optimize the feeding accuracy of each solar cell and the connecting sheet, the method can further comprise a positioning and detecting step for positioning and detecting the fed solar cell and the connecting sheet. The positioning and detecting step comprises the following sub-steps: presetting lamination characteristic parameters in a system; photographing the solar cell and the connecting sheet by using a camera device; extracting actual lamination parameters in the picture, and comparing the actual lamination parameters with the lamination characteristic parameters; if the comparison result is larger than the specific threshold value, judging that the lamination is poor and rectifying deviation.

Preferably, the positioning and detecting steps can be performed synchronously with the ordinary feeding step, specifically, the detecting device can feed back the detection result to the feeding device in a closed loop, and the feeding device can adjust the operation of the manipulator according to the detection result.

Also preferably, the above method further comprises the step of applying an adhesive (which may be a conductive adhesive or a non-conductive adhesive), which may also have a variety of preferred arrangements. For example, the method may further include the step of detecting the adhesive defects of the solar cell sheet and the connecting sheet to which the adhesive has been applied, the step including the sub-steps of: presetting a characteristic parameter of the adhesive in the system, which may be, for example, a suitable width, length, or thickness of the adhesive; photographing the applied adhesive by using a camera device; extracting actual parameters of the binder in the picture, and comparing the actual parameters with the characteristic parameters; and if the comparison result is larger than the specific defect threshold value, judging that the adhesive is not applied well. The above calculation and comparison steps may be performed through a UI window, and the calculation result may be further generated into a line graph, a scatter diagram, and the like. And if the adhesive is not applied well, removing the unit chip and carrying out patching subsequently.

The step of applying the adhesive and the step of detecting the adhesive defect are performed simultaneously, wherein the detection device feeds back the detection result to the device for applying the adhesive in a closed loop. The control module of the device for applying adhesive is able to adjust the operation of the robot according to the detection result. The device can correct the problems of possible adhesive loss, disconnection, printing offset and the like in time, and can improve the printing precision, quality and stability of the adhesive.

In addition, the impurities on the solar cell sheet and the tab sheet are blown away using an air blowing device while applying the adhesive.

The method may further comprise a subsequent curing step in which a double-layered curing hotplate may be provided, the cell string being positioned between the double-layered curing hotplates to complete the curing. Preferably, the method further includes a step of detecting the quality of the entire battery string.

According to the laminated assembly and the manufacturing method provided by the invention, the connecting sheet is arranged at the tail end of each battery string, so that the positive bus bar and the negative bus bar of the laminated assembly can be connected to the bottom surface of the battery string, and the bus bars cannot be seen on the top surface of the laminated assembly. The connecting sheet can be made of the same base material as that of the conventional solar cell, and the connecting sheet does not influence the thermal expansion coefficient of other solar cells. The connecting sheet can be a false sheet without a PN junction, a process similar to that of the solar cell can be adopted when the connecting sheet is manufactured, and meanwhile, unnecessary process steps are reduced, so that the manufacturing cost of the connecting sheet is lower.

The foregoing description of various embodiments of the invention is provided for the purpose of illustration to one of ordinary skill in the relevant art. It is not intended that the invention be limited to a single disclosed embodiment. As mentioned above, many alternatives and modifications of the present invention will be apparent to those skilled in the art of the above teachings. Thus, while some alternative embodiments are specifically described, other embodiments will be apparent to, or relatively easily developed by, those of ordinary skill in the art. The present invention is intended to embrace all such alternatives, modifications and variances of the present invention described herein, as well as other embodiments that fall within the spirit and scope of the present invention as described above.