Pattern printing, screen printing plate, method and main-grid-free battery piece

Abstract

The invention belongs to the technical field of battery pieces, and particularly relates to a printing pattern, a screen printing plate, a method and a main-grid-free battery piece. The substrate layer comprises fine grids which are discontinuously arranged; the stacked layer comprises connecting grids which are intermittently arranged, the connecting grids are arranged at the tops of the fine grids, and the two ends of the connecting grids extend to form connection of the fine grids; in short, the grid lines are arranged in a layered mode, the resistance value of the grid lines is effectively reduced while the high grid line height is obtained through two times of printing, the two ends of the connecting grid extend, and connection of the fine grid is completed.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery cells, and in particular relates to a printed pattern, a screen, a method and a main grid-free battery cell. Background Art

[0002] Cell grid line printing is a key process in the production of solar cells, and its quality directly affects the electrical performance and photoelectric conversion efficiency of the cell. Busbarless cells are a technology that further improves cell efficiency and reduces costs by eliminating the busbar on traditional solar cells. Existing busbarless cells are usually printed through screen printing, which involves placing silver paste on the screen, applying the paste with a scraper, and printing it evenly through the gaps onto the cell surface. The paste is then solidified through steps such as drying. However, if the existing printing method is printed too high, the two sides of the silver paste will collapse, resulting in a lower grid line height, resulting in a larger grid line resistance.

[0003] Therefore, how to avoid a high resistance of the gate line due to a low height of the gate line is a technical problem that needs to be solved urgently in the art.

[0004] It should be noted that the above information disclosed in this background technology section is only used to understand the background technology of the present application concept, and therefore, the above description is not considered to constitute information of the prior art. Summary of the invention

[0005] The embodiments of the present disclosure at least provide a printed pattern, a screen, a method and a busbar-free solar cell.

[0006] In a first aspect, an embodiment of the present disclosure provides a printed pattern, comprising: a plurality of grid lines, which include a base layer and an overlay layer; the base layer includes intermittently arranged fine grids; the overlay layer includes intermittently arranged connecting grids, the connecting grids are arranged on top of the fine grids, and the two ends of the connecting grids extend to form a connection between the fine grids.

[0007] In an optional embodiment, a coarse grid is arranged between the fine grids, and a connecting gap is arranged between the coarse grids and the fine grids; connecting points are arranged at both ends of the connecting grid, and the connecting points are arranged in the connecting gap to complete the connection between the coarse grid and the fine grid.

[0008] In an optional embodiment, the width of the fine grid is 15-25um, and the height thereof is 5-10um; and / or the width of the coarse grid is 100-500um, and the height thereof is 5-10um; and / or the spacing between the fine grid and the coarse grid is 0.5-1.5mm; and / or the width of the connecting grid is 20-25um, and the height thereof is 15-20um.

[0009] In the second aspect, the embodiments of the present disclosure also provide a printing screen, including: a main plate, which includes a frame and a main steel belt coated on the frame, the main steel belt is provided with a plurality of main printing grooves, the main printing grooves include a first through groove and a second through groove arranged at intervals, the first through groove is suitable for printing fine grids, and the second through groove is suitable for printing coarse grids; a sub-plate, which includes a frame and a sub-steel belt coated on the frame, the sub-steel belt is provided with a plurality of sub-printing grooves, the sub-printing grooves include a third through groove arranged at intervals, and the third through groove is suitable for printing connecting grids.

[0010] In a third aspect, the present disclosure also provides a printing method, including: Step S1, printing fine grids and coarse grids spaced apart on the surface of the cell; Step S2, drying the battery cell; Step S3, printing a connection grid on the top of the fine grid of the battery cell, with both ends of the connection grid collapsing into the gap between the fine grid and the coarse grid, thus completing the connection between the coarse grid and the fine grid; Step S4, drying the battery cell for a second time.

[0011] In an optional embodiment, in step S1, fine grids and coarse grids arranged at intervals are printed on the surface of the battery cell through a main plate of a printing screen; wherein the main plate includes a frame and a main steel belt wrapped on the frame, and a plurality of main printing grooves are provided on the main steel belt, and the main printing grooves include a first through groove and a second through groove arranged at intervals, the first through groove is suitable for printing fine grids, and the second through groove is suitable for printing coarse grids.

[0012] In an optional embodiment, in step S3, a connection grid is printed on the surface of the battery cell by means of a sub-plate of a printing screen; wherein the sub-plate includes a frame and a sub-steel belt wrapped on the frame, and a plurality of sub-printing grooves are provided on the sub-steel belt, and the sub-printing grooves include third through grooves arranged at intervals, and the third through grooves are suitable for printing the connection grid.

[0013] In a fourth aspect, the embodiments of the present disclosure further provide a main-grid-free solar cell, comprising: a silicon wafer; a top array of which is provided with gate lines, the gate lines comprising a base layer and an overlay layer; the base layer comprises intermittently arranged fine gates, coarse gates are arranged between the fine gates, and a connecting gap is arranged between the coarse gates and the fine gates; the overlay layer comprises intermittently arranged connecting gates, the connecting gates are arranged on the top of the fine gates, connecting points are arranged at both ends of the connecting gates, the connecting points are coated on both ends of the connecting gates, and the outer sides of the connecting points are connected to the coarse gates to complete the connection between the coarse gates and the fine gates.

[0014] In an optional embodiment, the width of the fine grid is 15-25um, and the height thereof is 5-10um; and / or the width of the coarse grid is 100-500um, and the height thereof is 5-10um; and / or the spacing between the fine grid and the coarse grid is 0.5-1.5mm; and / or the width of the connecting grid is 20-25um, and the height thereof is 15-20um.

[0015] In a fifth aspect, an embodiment of the present disclosure further provides a photovoltaic module, comprising: a packaging assembly; the above-mentioned busbar-free solar cell, wherein the silicon wafer is installed in the packaging assembly.

[0016] The beneficial effects of the present invention are that the printed pattern, screen, method and busbar-free solar cell arrange the grid lines in layers, obtain a higher grid line height through two printings, effectively reduce the resistance of the grid lines, and connect the two ends of the grid to extend and complete the connection of the fine grid.

[0017] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0018] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, this article specifically cites preferred embodiments and provides detailed descriptions as follows in conjunction with the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A top view of a printed graphic provided in an embodiment of the present disclosure; Figure 2 A cross-sectional view of a printed graphic provided by an embodiment of the present disclosure; Figure 3 A schematic diagram of the structure of a base layer and an overlay layer provided in an embodiment of the present disclosure; Figure 4 A top view of a master board provided in an embodiment of the present disclosure; Figure 5 A top view of a sub-plate provided in an embodiment of the present disclosure.

[0021] In the figure: 1. Grid line; 11, base layer; 11a, fine grid; 11b, coarse grid; 11c, connection gap; 12. Overlay layer; 12a. Connection grid; 12b. Connection point; 2. Main plate; 21. Main steel belt; 21a. Main printing groove; 21b. First through groove; 21c. Second through groove; 3. Sub-plate; 31. Sub-steel belt; 31a. Sub-printing groove; 31b. Third through groove. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In this article, when it is mentioned that the first component is located on the second component, this may mean that the first component may be directly formed on the second component, or the third component may be interposed between the first component and the second component. In addition, in the drawings, in order to effectively describe the technical content, the thickness of the components may be exaggerated or reduced.

[0024] The terms used herein are only used to describe specific exemplary configurations and are not intended to be limited. As used herein, the singular articles "one", "an" and "the" may also be intended to include plural forms, unless it is clearly indicated above that this is not the case. The terms "comprise", "include" and "have" are inclusive, and therefore specify the presence of features, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components and / or combinations thereof. The method steps, processes and operations described herein should not be interpreted as necessarily requiring them to be performed in the specific order discussed or shown, unless specifically identified as an execution order. Additional or alternative steps may be adopted.

[0025] As used herein, the phrases "in one embodiment," "according to one embodiment," "in some embodiments," and the like generally refer to the fact that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure. Therefore, a particular feature, structure, or characteristic may be included in more than one embodiment of the present disclosure, so that these phrases do not necessarily refer to the same embodiment. As used herein, the terms "example," "exemplary," and the like are used to "serve as an example, instance, or illustration." Any implementation, aspect, or design described herein as "example" or "exemplary" is not necessarily to be construed as preferred or superior to other implementations, aspects, or designs. On the contrary, the use of the terms "example," "exemplary," and the like is intended to present concepts in a concrete manner.

[0026] Through research, it is found that in the prior art, when printing graphics, due to the fluidity of the slurry, the gate lines printed on the surface of the battery cell will collapse to both sides, and the height of the resulting gate lines will be high, resulting in a large resistance value of the gate lines, which is the problem and purpose to be solved by the invention.

[0027] Based on the above research, the embodiments of the present disclosure provide a printed pattern, a screen, a method and a busbar-free solar cell, which increase the height of the grid line and reduce the resistance of the grid line by printing twice.

[0028] The defects existing in the above solutions are the results obtained by the inventor after practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed by the present invention in this article for the above problems should be the contributions made by the inventor to the present invention during the disclosure process.

[0029] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0030] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0031] See also Figures 1 to 3 , Figure 1-Figure 3 A printed pattern is shown, comprising: a plurality of gate lines 1, which include a base layer 11 and an overlay layer 12; the base layer 11 includes intermittently arranged fine gates 11a; the overlay layer 12 includes intermittently arranged connecting gates 12a, the connecting gates 12a are arranged on the top of the fine gates 11a, and the two ends of the connecting gates 12a extend to form a connection of the fine gates 11a; in short, by arranging the gate lines 1 in layers, a higher height of the gate lines 1 is obtained by printing twice, while the resistance of the gate lines 1 is effectively reduced, and the two ends of the connecting gates 12a are extended to complete the connection of the fine gates 11a.

[0032] In some embodiments, Figure 1-Figure 3 It is shown that a coarse grid 11b is arranged between the fine grids 11a, and a connecting gap 11c is arranged between the coarse grids 11b and the fine grids 11a; connecting points 12b are arranged at both ends of the connecting grid 12a, and the connecting points 12b are stuck in the connecting gap 11c to complete the connection between the coarse grid 11b and the fine grid 11a; in short, the connecting points 12b at both ends of the connecting grid 12a are stuck in the connecting gap 11c to complete the connection between the coarse grid 11b and the fine grid 11a.

[0033] In some embodiments, Figure 1-Figure 3 It is shown that the width of the fine grid 11a is 15-25um and the height is 5-10um; and / or the width of the coarse grid 11b is 100-500um and the height is 5-10um; and / or the spacing between the fine grid 11a and the coarse grid 11b is 0.5-1.5mm; and / or the width of the connecting grid 12a is 20-25um and the height is 15-20um; in short, the width of the fine grid 11a is slightly smaller, and collapse may occur during printing and drying, resulting in a slight increase in the final width. The connecting grid 12a is printed on the top of the fine grid 11a to increase the overall height of the grid line 1.

[0034] See also Figures 4 to 5 The present embodiment further provides a printing screen, comprising: a main plate 2, which comprises a frame and a main steel strip 21 coated on the frame, the main steel strip 21 is provided with a plurality of main printing grooves 21a, the main printing grooves 21a comprise a first through groove 21b and a second through groove 21c arranged at intervals, the first through groove 21b is suitable for printing a fine grid 11a, and the second through groove 21c is suitable for printing a coarse grid 11b; a sub-plate 3, which comprises a frame and a sub-steel strip 31 coated on the frame, the sub-steel strip 31 is provided with a plurality of sub-printing grooves 31a, the sub-printing grooves 31a comprise a third through groove 31b arranged at intervals, the third through groove 31b is suitable for printing a connecting grid 12a; in short, the first through groove 21b and the second through groove 21c are engraved on the surface of the main steel strip 21, and are responsible for printing the coarse grid 11b and the fine grid 11a; the third through groove 31b is engraved on the surface of the sub-steel strip 31, and is responsible for printing the connecting grid 12a.

[0035] This embodiment also provides a printing method, including: Step S1, printing fine grids 11a and coarse grids 11b spaced apart on the surface of the cell; Step S2, drying the battery cell; Step S3, printing the connection grid 12a on the top of the fine grid 11a of the cell, and the two ends of the connection grid 12a collapse to within the gap between the fine grid 11a and the coarse grid 11b, thus completing the connection between the coarse grid 11b and the fine grid 11a; Step S4, drying the battery cell for a second time.

[0036] In some embodiments, in step S1, fine grids 11a and coarse grids 11b arranged at intervals are printed on the surface of the battery cell by a main plate 2 of a printing screen; wherein the main plate 2 comprises a frame and a main steel belt 21 wrapped on the frame, and a plurality of main printing grooves 21a are provided on the main steel belt 21, and the main printing grooves 21a comprise first through grooves 21b and second through grooves 21c arranged at intervals, and the first through grooves 21b are suitable for printing the fine grids 11a, and the second through grooves 21c are suitable for printing the coarse grids 11b; in short, the battery cell is firstly transported to the bottom of the main plate 2, and a scraper prints silver paste onto the surface of the battery cell, and prints the fine grids 11a and coarse grids 11b on the surface of the battery cell; In some embodiments, in step S3, a connection grid 12a is printed on the surface of the battery cell by means of a sub-plate 3 of a printing screen; wherein the sub-plate 3 comprises a frame and a sub-steel belt 31 wrapped on the frame, and a plurality of sub-printing grooves 31a are provided on the sub-steel belt 31, and the sub-printing grooves 31a comprise third through grooves 31b arranged at intervals, and the third through grooves 31b are suitable for printing the connection grid 12a; in short, after one printing is completed, the dried battery cell is conveyed to the bottom of the sub-plate 3, and a scraper is used to print the top of the fine grid 11a of the silver paste printing paper to form the connection grid 12a, complete the connection between the coarse grid 11b and the fine grid 11a, and increase the height of the fine grid 11a.

[0037] The present embodiment also provides a busbar-free solar cell, comprising: a silicon wafer; a top array of which is provided with a gate line 1, wherein the gate line 1 comprises a base layer 11 and an overlay layer 12; the base layer 11 comprises intermittently arranged fine gates 11a, wherein a coarse gate 11b is arranged between the fine gates 11a, and a connecting gap 11c is arranged between the coarse gate 11b and the fine gate 11a; the overlay layer 12 comprises intermittently arranged connecting gates 12a, wherein the connecting gate 12a is arranged on the top of the fine gate 11a, and connecting points 12b are arranged at both ends of the connecting gate 12a, wherein the connecting points 12b are coated on both ends of the connecting gate 12a, and the outer side of the connecting point 12b is connected to the coarse gate 11b, so as to complete the connection between the coarse gate 11b and the fine gate 11a.

[0038] In some embodiments, the width of the fine gate 11a is 15-25um, and its height is 5-10um; and / or the width of the coarse gate 11b is 100-500um, and its height is 5-10um; and / or the spacing between the fine gate 11a and the coarse gate 11b is 0.5-1.5mm; and / or the width of the connecting gate 12a is 20-25um, and its height is 15-20um.

[0039] This embodiment further provides a photovoltaic assembly, comprising: a packaging assembly; the above-mentioned busbar-free solar cell, wherein the silicon wafer is installed in the packaging assembly.

[0040] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, terms such as "first", "second" and other numerical terms do not imply an order or sequence when used in this document unless explicitly indicated above. Therefore, without departing from the teachings of the example embodiments, the first element, component, region, layer or section discussed above may be referred to as a second element, component, region, layer or section.

[0042] Spatially relative terms, such as "inside", "outside", "below", "below", "down", "above", "on", etc., may be used herein to facilitate description of the relationship of one element or feature to another element or feature as illustrated in the figure. In addition to the orientation depicted in the figure, spatially relative terms may be intended to cover different orientations of the device in use or operation. For example, if the device in the figure is turned over, the elements described as "below" or "below" other elements or features will be oriented to be "above" other elements or features. Therefore, the example term "below" can cover the orientation above and below. The device can be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein are interpreted accordingly.

[0043] In the above discussion, unless otherwise stated, the terms "about," "approximately," "substantially," etc., when used to describe a numerical value, mean a variation of + / - 10% of the value.

[0044] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A printed graphic, characterized in that: include: A plurality of grid lines (1), comprising a base layer (11) and a superposition layer (12); The base layer (11) comprises intermittently arranged fine grids (11a); The stacked layer (12) comprises a discontinuously arranged connection grid (12a), wherein the connection grid (12a) is arranged on the top of the fine grid (11a), and the two ends of the connection grid (12a) extend to form a connection with the fine grid (11a).

2. The printed pattern according to claim 1, characterized in that Coarse grids (11b) are arranged between the fine grids (11a), and connecting gaps (11c) are arranged between the coarse grids (11b) and the fine grids (11a); Connection points (12b) are provided at both ends of the connection grid (12a), and the connection points (12b) are clamped in the connection gap (11c) to complete the connection between the coarse grid (11b) and the fine grid (11a).

3. The printed pattern according to claim 2, characterized in that The width of the fine grid (11a) is 15-25 um and the height is 5-10 um; and / or The width of the coarse grid (11b) is 100-500um, and the height is 5-10um; and / or The spacing between the fine grid (11a) and the coarse grid (11b) is 0.5-1.5 mm; and / or The width of the connection grid (12a) is 20-25 um, and the height is 15-20 um.

4. A printing screen, characterized in that: include: A main plate (2), comprising a frame and a main steel strip (21) wrapped around the frame, the main steel strip (21) being provided with a plurality of main printing grooves (21a), the main printing grooves (21a) comprising first through grooves (21b) and second through grooves (21c) arranged at intervals, the first through grooves (21b) being suitable for printing fine grids (11a), and the second through grooves (21c) being suitable for printing coarse grids (11b); A secondary plate (3) comprises a frame and a secondary steel belt (31) wrapped around the frame, wherein the secondary steel belt (31) is provided with a plurality of secondary printing grooves (31a), wherein the secondary printing grooves (31a) comprise third through grooves (31b) arranged at intervals, and wherein the third through grooves (31b) are suitable for printing a connection grid (12a).

5. A method for printing a printed pattern as claimed in any one of claims 1 to 3, characterized in that: include: Step S1, printing fine grids (11a) and coarse grids (11b) spaced apart on the surface of the battery cell; Step S2, drying the battery cell; Step S3, printing a connection grid (12a) on top of the fine grid (11a) of the battery cell, with both ends of the connection grid (12a) collapsing into the gap between the fine grid (11a) and the coarse grid (11b), thereby completing the connection between the coarse grid (11b) and the fine grid (11a); Step S4, drying the battery cell for a second time.

6. The printing method according to claim 5, characterized in that In the step S1, fine grids (11a) and coarse grids (11b) arranged at intervals are printed on the surface of the battery cell by using a main plate (2) of a printing screen; The main plate (2) comprises a frame and a main steel belt (21) wrapped around the frame. The main steel belt (21) is provided with a plurality of main printing grooves (21a). The main printing grooves (21a) comprise first through grooves (21b) and second through grooves (21c) arranged at intervals. The first through grooves (21b) are suitable for printing fine grids (11a), and the second through grooves (21c) are suitable for printing coarse grids (11b).

7. The printing method according to claim 6, characterized in that In the step S3, a connection grid (12a) is printed on the surface of the battery cell by using a sub-plate (3) of the printing screen; The secondary plate (3) comprises a frame and a secondary steel belt (31) wrapped around the frame, the secondary steel belt (31) is provided with a plurality of secondary printing grooves (31a), the secondary printing grooves (31a) include third through grooves (31b) arranged at intervals, and the third through grooves (31b) are suitable for printing the connection grid (12a).

8. A busbar-free solar cell, characterized in that: include; Silicon wafer; The top array is provided with a grid line (1), and the grid line (1) comprises a base layer (11) and a superposition layer (12); The base layer (11) comprises intermittently arranged fine grids (11a), coarse grids (11b) are arranged between the fine grids (11a), and a connecting gap (11c) is arranged between the coarse grids (11b) and the fine grids (11a); The stacked layer (12) comprises a discontinuously arranged connection grid (12a), the connection grid (12a) being arranged on the top of the fine grid (11a), connection points (12b) being arranged at both ends of the connection grid (12a), the connection points (12b) being coated on both ends of the connection grid (12a), and The outer side of the connection point (12b) is connected to the coarse grid (11b) to complete the connection between the coarse grid (11b) and the fine grid (11a).

9. The busbar-free solar cell according to claim 8, characterized in that: The width of the fine grid (11a) is 15-25 um and the height is 5-10 um; and / or The width of the coarse grid (11b) is 100-500um, and the height is 5-10um; and / or The spacing between the fine grid (11a) and the coarse grid (11b) is 0.5-1.5 mm; and / or The width of the connection grid (12a) is 20-25 um, and the height is 15-20 um.

10. A photovoltaic module, characterized in that: include: Packaging components; The busbar-less solar cell according to any one of claims 8 to 9, wherein the silicon wafer is installed in a packaging assembly.

Images