Adhesive dispensing assembly, preparation method of main-grid-free battery assembly and main-grid-free battery assembly

Abstract

The invention discloses a dispensing assembly, a preparation method of a main-grid-free battery assembly and the main-grid-free battery assembly, and the main-grid-free battery assembly comprises a plurality of main-grid-free battery pieces which comprise a plurality of auxiliary grids which are arranged in parallel; a plurality of groups of glue points, each group of glue points is arranged along the arrangement direction of the auxiliary grid, the middle part of each glue point is provided with a bearing groove for bearing a welding strip, the bottom of each bearing groove is through along the direction vertical to the battery piece, or the thickness of the bottom of each bearing groove is not greater than the height of the auxiliary grid; and the welding strip is located in the bearing groove of the group of glue points, and the welding strip is in contact with the auxiliary grid. According to the invention, the bearing groove can support the welding strip, and during lamination, the welding strip is in full contact with the auxiliary grid, so that alloy can be better formed in the subsequent welding process, and the EL blackening phenomenon cannot be generated; the distance between the welding strip and the main-grid-free battery piece can be reduced, the situation that the adhesive film enters a gap between the welding strip and the main-grid-free battery piece is reduced as much as possible, the situation that the adhesive film is aged subsequently to drive the welding strip to fall off to form a delaminated layer visible in appearance is prevented, and the reliability is improved.

Description

Technical Field

[0001] The present invention relates to the photovoltaic field, and in particular to a glue dispensing component, a preparation method of a busbar-free battery component, and a busbar-free battery component. Background Art

[0002] The electrodes of crystalline silicon cells are composed of a main grid and a secondary grid. The secondary grid is responsible for collecting current and transmitting it to the main grid, while the main grid is responsible for connecting to the welding strip and transmitting it to the welding strip. Increasing the number of main grids can improve cell efficiency and component power, but it will also increase the consumption of main grid paste and increase costs. In addition, one of the main costs of current cell cells is the high consumption of silver paste for the grid lines. The main grid-free crystalline silicon cell interconnection technology eliminates the main grid and allows the welding strip to be directly connected to the secondary grid, which can reduce the consumption of paste and thus reduce costs.

[0003] However, how to ensure effective contact between the welding strip and the auxiliary grid is a major problem in the industry.

[0004] In view of this, it is necessary to provide an improved dispensing assembly, a method for preparing a busbar-free battery assembly, and a busbar-free battery assembly to solve the above technical problems. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art, and provides a dispensing assembly, a method for preparing a main grid-free battery assembly, and a main grid-free battery assembly.

[0006] In order to achieve one of the above-mentioned invention objects, the present invention adopts the following technical solution:

[0007] A main grid-free battery assembly, comprising:

[0008] A plurality of main-grid-free solar cells, including a plurality of auxiliary grids arranged in parallel;

[0009] A plurality of groups of glue points, each group of glue points is arranged along the arrangement direction of the auxiliary grid, the middle of the glue points has a supporting groove for supporting the welding strip, the bottom of the supporting groove is through in a direction perpendicular to the battery sheet, or the bottom thickness of the supporting groove is not greater than the height of the auxiliary grid;

[0010] The welding strip is located in a supporting groove of a group of glue points, and the welding strip is in contact with the auxiliary grid.

[0011] Furthermore, the glue dots include two sub-glue dots spaced apart along the extension direction of the secondary grid lines, and the supporting groove is formed between the two sub-glue dots.

[0012] Furthermore, the cross section of the supporting groove matches the cross section of the welding strip.

[0013] Furthermore, the glue dots are located between adjacent sub-grids.

[0014] A dispensing component, comprising:

[0015] A screen, the screen comprising a plurality of scraping grooves arranged in parallel, and a plurality of glue dispensing holes arranged at intervals along the extending direction of the scraping grooves, wherein the glue dispensing holes comprise two sub-holes arranged at intervals along the width direction of the scraping grooves, and the sub-holes are connected to the scraping grooves;

[0016] The scraper is used to scrape off the glue coated in the scraping groove.

[0017] Furthermore, along the width direction of the scraping groove, the size of the bottom of the scraping groove is smaller than the size of the top thereof.

[0018] Furthermore, the cross section of the scraping groove is arc-shaped or polygonal; or the cross section of the scraping groove is consistent with at least a part of the cross section of the welding strip to be fixed.

[0019] Furthermore, the sub-holes overlap with the edges on both sides of the scraping groove in the width direction, and the bottom wall of the scraping groove is located between the sub-holes.

[0020] Furthermore, the two sub-holes are symmetrically arranged along the central axis of the scraping groove.

[0021] Furthermore, the scraper includes a scraper plate and a scraper block located at the bottom of the scraper plate and extending into the scraper groove, and the size of the scraper block is not greater than the size of the scraper groove.

[0022] Furthermore, the cross section of the scraping block is consistent with the cross section of the scraping groove.

[0023] A method for preparing a busbar-free battery assembly adopts the glue-dispensing assembly to form glue dots on the surface of a busbar-free battery sheet.

[0024] Furthermore, the method for preparing the busbar-free battery assembly comprises the following steps:

[0025] The screen is laid on the surface of the busbar-free solar cell, the scraping groove extends along the arrangement direction of a plurality of sub-grids of the busbar-free solar cell, and the glue dispensing holes are staggered with the sub-grids;

[0026] Applying glue in the scraping groove;

[0027] The glue applied in the scraping groove is scraped off by a scraper to form glue dots at the glue dispensing holes.

[0028] Furthermore, the glue dispensing hole is located between two adjacent secondary grid lines, and the glue dispensing hole is arranged close to one of the secondary grid lines.

[0029] Furthermore, the scraper includes a scraper plate and a scraper block located at the bottom of the scraper plate and extending into the scraper groove, and the scraper block moves along the extension direction of the scraper groove to scrape off the glue.

[0030] Furthermore, forming a glue spot thickness on the surface of the busbar-free solar cell also includes the following steps:

[0031] Fixing the welding ribbon on the busbar-free solar cell through the glue point, the welding ribbon connecting the front side of a busbar-free solar cell and the back side of an adjacent busbar-free solar cell;

[0032] Applying pressure, the welding strip contacts the secondary grid of the battery cell without main grid;

[0033] Heat treatment, the heat treatment temperature is 5°C to 30°C higher than the melting point of the welding strip, the time is 10s to 40s, so that an alloy is formed between the welding strip and the auxiliary grid.

[0034] The beneficial effects of the present invention are as follows: in the main-grid-free battery assembly of the present invention, the bottom of the supporting groove in the middle of the glue point is penetrated in a direction perpendicular to the battery cell, or the bottom thickness of the supporting groove is not greater than the height of the auxiliary grid, so that the supporting groove can support the welding strip, and during lamination, the welding strip is in full contact with the auxiliary grid, and an alloy can be better formed in the subsequent welding process without EL blackening; it can also reduce the distance between the welding strip and the main-grid-free battery cell, minimize the glue film from entering the gap between the welding strip and the main-grid-free battery cell, prevent the subsequent aging of the glue film from causing the welding strip to fall off to form delamination visible in appearance, and improve reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a busbar-free solar cell according to an embodiment of the present invention, (a) is the front side of the solar cell, and (b) is the back side of the solar cell;

[0036] Figure 2 is a schematic diagram of the structure of a battery string in one embodiment of the present invention;

[0037] Figure 3 for Figure 2 A schematic diagram from another angle;

[0038] Figure 4 for Figure 2 Schematic diagram of glue dots on a busbar-less cell;

[0039] Figure 5 for Figure 4 A schematic diagram from another angle;

[0040] Figure 6 A schematic diagram of the screen structure of a preferred embodiment of the present invention;

[0041] Figure 7 for Figure 6 A partial enlarged view of the center glue hole;

[0042] Figure 8 for Figure 6A top view of

[0043] Fig. 9 for Figure 8 Cross-sectional view along AA direction;

[0044] Fig.10 A schematic structural diagram of a scraper according to a preferred embodiment of the present invention;

[0045] Fig.11 for Fig.10 Exploded diagram of

[0046] Fig.12 for Fig.10 A schematic diagram from another angle;

[0047] Fig.13 This is a schematic diagram of the coordination of a main grid-free solar cell, screen, and scraper during dispensing;

[0048] Fig.14 for Fig.13 A schematic diagram from another angle;

[0049] Fig.15 The images under a microscope after the welding strip falls off are: (a) welding the welding strip by conventional glue points, and (b) welding the welding strip by using the glue points obtained by the present invention.

[0050] Among them, 1-main-gridless battery cell, 11-auxiliary grid, 12-connecting grid, 2-welding strip, 3-glue point, 31-supporting groove, 32-sub-glue point, 4-glue dispensing assembly, 41-screen, 411-scraping groove, 412-glue dispensing hole, 42-scraper, 421-scraper, 422-scraper block, 423-handheld part. DETAILED DESCRIPTION

[0051] The present invention will be described in detail below in conjunction with the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional changes made by a person skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0052] In the various drawings of the present invention, for the convenience of illustration, some sizes of structures or parts are exaggerated relative to other structures or parts, and thus, they are only used to illustrate the basic structure of the subject matter of the present invention.

[0053] Please refer to Figure 1 to Figure 5 As shown, a busbar-free battery assembly of a preferred embodiment of the present invention comprises a plurality of busbar-free battery cells 1 and a plurality of welding strips 2. Each of the welding strips 2 is fixed to the busbar-free battery cell 1 by a group of glue dots 3. The plurality of welding strips 2 connect adjacent busbar-free battery cells 1 in series.

[0054] The busbar-free cell 1 can be a single-sided cell with a busbar on the front and no busbar on the back; or a double-sided cell with busbars on both the front and back. "Busbar-free" means: only a secondary busbar 11 is provided on the side with busbars, with no busbar at all; or a portion of the busbar is retained or a small portion of the connecting busbar 12 is retained.

[0055] like Figure 1 As shown, the front side of the busbar-free solar cell 1 is provided with grid lines, and the back side is free of grid lines. Specifically, the grid lines on the front side include a plurality of sub-grids 11 arranged in parallel, and a plurality of groups of connecting grids 12 connecting part of the sub-grids 11 at the edges, each group of connecting grids 12 is located at the position where the welding strip 2 is laid, and each group of connecting grids 12 includes two connecting grids 12 arranged at intervals along the extension direction of the sub-grid 11, the sub-grid 11 is interrupted between the two connecting grids 12, and the welding strip 2 passes through a group of connecting grids 12, which can reduce the edge hidden crack phenomenon.

[0056] The present invention mainly improves the fixing method of the welding strip 2 on the side with the grid line. The front of the main grid-free battery is provided with a plurality of groups of glue points 3, and each group of glue points 3 is arranged along the arrangement direction of the auxiliary grid 11 to fix the welding strip 2. At this time, the welding strip 2 is perpendicular to the auxiliary grid 11.

[0057] Specifically, the glue dots 3 are located between adjacent auxiliary grids 11 , and do not cover the auxiliary grids 11 , thereby ensuring effective contact between the welding strip 2 and the auxiliary grids 11 .

[0058] Different from the traditional rectangular glue dots 3 , the glue dots 3 of the present invention have a supporting groove 31 in the middle to support the soldering strip 2 ; the soldering strip 2 is located in the supporting groove 31 of a group of glue dots 3 to achieve contact with the auxiliary grid 11 .

[0059] In this embodiment, the bottom of the supporting groove 31 is through in a direction perpendicular to the battery cell, that is, the bottom of the supporting groove 31 is hollow. Specifically, the glue point 3 includes two sub-glue points 32 spaced apart along the extension direction of the auxiliary grid 11, the inner side surfaces of the two sub-glue points 32 together constitute the supporting groove 31, and the middle of the two sub-glue points 32 is hollow.

[0060] The middle part of the glue spot 3 is hollowed out, which can support the welding ribbon 2. During lamination, the welding ribbon 2 penetrates the glue spot 3 and is in full contact with the auxiliary grid 11, so that an alloy can be better formed in the subsequent welding process without causing EL blackening. It can also reduce the distance between the welding ribbon 2 and the main grid-free battery cell 1, minimize the entry of the glue film into the gap between the welding ribbon 2 and the main grid-free battery cell 1, prevent the subsequent aging of the glue film from causing the welding ribbon 2 to fall off, forming visible delamination in appearance, and improving reliability.

[0061] In another embodiment, the bottom of the supporting groove 31 is not through, but the thickness of the bottom is not greater than the height of the auxiliary grid 11. When pressed down, the soldering tape 2 can also effectively contact the auxiliary grid 11 to avoid EL blackening.

[0062] Furthermore, based on all the above embodiments, the cross-section of the supporting groove 31 matches the cross-section of the solder strip 2, that is, the side wall of the supporting groove 31 matches the shape and size of the solder strip 2, and can just support the solder strip 2 to prevent the glue point 3 from being squeezed by the solder strip 2, thereby avoiding overflow of the glue point 3, and will not further increase the shielding area of ​​the battery cell, nor will it cover the auxiliary grid 11, thereby avoiding blackening of the EL.

[0063] When there is no grid line on the back side, there is no need to consider the connection between the welding ribbon 2 and the auxiliary grid 11, and any shape of glue point 3 can be used. When there is a grid line on the back side like the front side, the shape of the glue point 3 is the same as above, and no further description is given here. The welding ribbon 2 connects the front side of a non-busbar battery cell 1 and the back side of an adjacent non-busbar battery cell 1 through the glue point 3 to form a battery string.

[0064] See also Figure 6 to Figure 14 As shown, the dispensing assembly 4 of a preferred embodiment of the present invention is used to form the above-mentioned glue dots 3 on the main grid-free battery cell 1, improve the contact between the welding strip 2 and the auxiliary grid 11, and solve the problem that the welding strip 2 cannot be alloyed with the auxiliary grid 11 at the position of the glue dots 3.

[0065] The glue dispensing assembly 4 includes a screen 41 and a scraper 42 used in conjunction with the screen 41, which is used to form a plurality of glue dots 3 on the busbar-free cell sheet 1 by scraping, thereby greatly improving the glue dispensing efficiency.

[0066] The screen 41 is a mask for glue dispensing, which determines the distribution and shape of the glue dots 3. The screen 41 includes a plurality of scraping grooves 411 arranged in parallel, and a plurality of glue dispensing holes 412 arranged at intervals along the extending direction of the scraping grooves 411. The scraping grooves 411 are used to accommodate glue, and the glue dispensing holes 412 are connected to the scraping grooves 411, and the glue dispensing holes 412 are through holes for glue to pass through and remain on the main grid-free battery cell 1.

[0067] A number of the scraping grooves 411 are arranged corresponding to a number of welding strips 2. Along the width direction of the scraping grooves 411, the size of the bottom of the scraping grooves 411 is smaller than the size of the top, that is, it is wider at the top and narrower at the bottom, which facilitates the insertion of the scraper 42. The shape design of the scraping grooves 411 determines the shape of the glue dots 3 to a certain extent, which will be described in detail in the glue dispensing method below.

[0068] Specifically, the cross section of the scraping groove 411 is arc-shaped or polygonal; or, the cross section of the scraping groove 411 is consistent with a part of the cross section of the welding strip 2 , so the supporting groove 31 formed on the glue point 3 plays a good supporting role for the welding strip 2 .

[0069] The glue dispensing hole 412 includes two sub-holes arranged at intervals along the width direction of the scraping groove 411, and the sub-holes are connected to the scraping groove 411; when dispensing glue, glue is applied to the scraping groove 411, and the glue can pass through the glue dispensing hole 412 and drip onto the main-grid-free battery cell 1 to form a glue spot 3, and the excess glue in the scraping groove 411 is scraped off by the scraper 42, and the shape of the glue spot 3 is corrected at the same time.

[0070] Preferably, the distance between the two sub-holes is smaller than the distance at the opening of the scraping groove 411, that is, the sub-holes overlap with the two side edges of the scraping groove 411 in the width direction; the bottom wall of the scraping groove 411 is located between the sub-holes, dividing the two sub-holes into two independent holes. It can be understood by those skilled in the art that the width of the bottom wall located between the two sub-holes is the distance between the two sub-holes.

[0071] In other words, the projections of the two sub-holes on the plane where the screen 41 is located are arranged at intervals, and the projections of the sub-holes overlap with the edges of the projections of the scraping grooves 411 on the plane where the screen 41 is located.

[0072] More preferably, the two sub-holes are symmetrically arranged along the central axis of the scraping groove 411 to form two symmetrically arranged sub-glue points 32.

[0073] Please refer to Figure 10 to Figure 14 As shown, the scraper 42 includes a scraper plate 421 and a scraper block 422 located at the bottom of the scraper plate 421 and extending into the scraper groove 411. The size of the scraper block 422 is less than or equal to the size of the scraper groove 411. The scraper block 422 moves along the scraper groove 411 to scrape off excess glue, and at the same time, trims the glue point 3 to expose the inner wall of the scraper groove 411, and forms a supporting groove 31 on the glue point 3 to support the welding strip 2.

[0074] Preferably, the cross section of the scraper block 422 is consistent with the cross section of the scraper groove 411 , so the scraper block 422 can move smoothly in the scraper groove 411 and scrape off all the glue in the scraper groove 411 , and the inner wall of the formed glue spot 3 is consistent with the scraper groove 411 .

[0075] Furthermore, the scraper 42 also includes a hand-held portion 423, and the hand-held portion 423 is detachably connected to the scraper 421 for easy operation.

[0076] The present invention further provides a method for preparing a busbar-free battery assembly, which uses the above-mentioned glue dispensing assembly 4 to form glue dots 3 on the surface of the busbar-free battery sheet 1.

[0077] Specifically, the dispensing process includes the following steps:

[0078] S1: laying the screen 41 on the surface of the busbar-free solar cell 1, so that the scraping groove 411 extends along the arrangement direction of the plurality of sub-grids 11 of the busbar-free solar cell 1, and the glue-dotting holes 412 are staggered with the sub-grids 11 to prevent the formed glue dots 3 from covering the sub-grids 11;

[0079] S2: Apply glue in the scraping groove 411;

[0080] S3 scrapes away the excess glue in the scraping groove 411 by the scraper 42 , and only forms glue dots 3 at the glue dispensing holes 412 .

[0081] Specifically, in S1, glue dots 3 need to be applied on both sides of the non-busbar cell 1. Usually, the number of glue dots 3 corresponding to each welding strip 2 on one cell is 2 to 50. The surface with grid lines adopts the direction of the present invention, and the surface without grid lines can be glued by any method.

[0082] The glue used in S2 is preferably UV glue, and the glue point 3 is solidified by irradiating ultraviolet light, which is convenient to operate and highly efficient.

[0083] During the scraping in S3, the scraping block 422 moves along the extending direction of the scraping groove 411 to scrape off the glue, which is easy to operate.

[0084] Furthermore, a glue spot 3 is formed on the busbar-free cell sheet 1, and the method for preparing the photovoltaic module further comprises the following steps:

[0085] The welding ribbon 2 is fixed on the busbar-free solar cell 1 through the glue point 3, and the welding ribbon 2 connects the front side of a busbar-free solar cell 1 and the back side of an adjacent busbar-free solar cell 1;

[0086] Applying pressure so that the welding strip 2 contacts the secondary grid 11 of the battery cell 1 without a main grid;

[0087] Heat treatment, the heat treatment temperature is 5° C. to 30° C. higher than the melting point of the welding strip 2 , and the time is 10s to 40s, so that an alloy is formed between the welding strip 2 and the auxiliary grid 11 .

[0088] Specifically, the first welding ribbon 2 is placed on the workbench, and then the busbar-free solar cell 1 is placed on the first welding ribbon 2, the first welding ribbon 2 is aligned with the glue point 3 on the back of the busbar-free solar cell 1, and the platform has suction force, so that the busbar-free solar cell 1 and the first welding ribbon 2 are closely attached;

[0089] The second welding ribbon 2 is placed on the front side of the busbar-free solar cell 1, the second welding ribbon 2 is aligned with the glue point 3 on the front side, and a press is placed on the second welding ribbon 2 to make the second welding ribbon 2 fit tightly with the solar cell.

[0090] The suction force of the platform and the pressure of the pressing tool are both part of the pressure application process, and the purpose is to ensure the contact between the soldering ribbon 2 and the secondary grid 11. For UV glue, ultraviolet light is used for 1s to 3s to solidify the glue point 3 and bond the soldering ribbon 2 and the main grid-free solar cell 1.

[0091] One side of the second welding ribbon 2 extends out of the busbar-less solar cell 1, and the next busbar-less solar cell 1 is placed on the extended portion of the welding ribbon 2, and the cycle continues to form a battery string.

[0092] Then the battery string is heat treated. During the heat treatment, the platform suction and the front pressure tool make the welding strip 2 fit closely with the auxiliary grid 11. The heat treatment temperature is 5℃~30℃ higher than the melting point of the welding strip 2, and the time is 10s~40s, so that an alloy is formed between the welding strip 2 and the auxiliary grid 11. The time required for the alloying of the welding strip 2 and the auxiliary grid 11 depends on the difference between the heat treatment temperature and the melting point of the welding strip 2. Generally, the heat treatment temperature is about 40℃ higher than the melting point of the welding strip 2, and the heat treatment time only takes 1s~3s. The present invention controls the difference between the heat treatment temperature and the melting point of the welding strip 2 to 5℃~30℃, so that the time required for alloying is controlled to 10s~40s. On the one hand, the reduction of the heat treatment temperature can reduce the stress at the connection between the welding strip 2 and the auxiliary grid 11, and improve the reliability of the component. On the other hand, the alloying time of the battery string is controlled to 10s~40s, which will not affect the production capacity.

[0093] The battery strings are stacked and then laminated. The lamination temperature is 100° C. to 150° C., which is lower than the melting point of the soldering strip 2 . There will be no further alloying between the soldering strip 2 and the auxiliary grid 11 .

[0094] The main grid-free crystalline silicon cell can be a PERC cell, a TOPCon cell or a HJT cell. The melting point of the solder strip 2 is 150°C to 200°C, and the composition of the surface tin layer is tin-lead, tin-lead-bismuth, tin-bismuth-silver, etc. The specific composition and melting point are selected according to the type of crystalline silicon cell used.

[0095] Please refer to Fig.15 As shown, the conventional glue point 3 is used to weld the welding strip 2. From the image under the microscope after the welding strip 2 falls off, it can be seen that the auxiliary grid 11 is not broken, indicating that the welding strip 2 is not in sufficient contact with the auxiliary grid 11, which will cause the EL to turn black, reduce the collection current, and reduce the reliability. However, from the image under the microscope after the welding strip 2 falls off, it can be seen that the image after the auxiliary grid 11 is welded at the non-glue point 3 is obviously broken after the welding strip 2 is pulled off, indicating that the welding strip 2 is in sufficient contact with the auxiliary grid 11.

[0096] In summary, in the main-grid-free battery assembly of the present invention, the bottom of the supporting groove 31 in the middle of the glue point 3 is through in a direction perpendicular to the battery cell, or the bottom thickness of the supporting groove 31 is not greater than the height of the auxiliary grid 11, so that the supporting groove 31 can support the welding strip 2, and during lamination, the welding strip 2 is in full contact with the auxiliary grid 11, and can better form an alloy in the subsequent welding process without EL blackening; it can also reduce the distance between the welding strip 2 and the main-grid-free battery cell 1, minimize the glue film from entering the gap between the welding strip 2 and the main-grid-free battery cell 1, prevent the subsequent aging of the glue film from causing the welding strip 2 to fall off, forming visible delamination in appearance, and improving reliability.

[0097] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0098] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A busbar-free battery assembly, characterized in that: include: A plurality of main-grid-free solar cells, including a plurality of auxiliary grids arranged in parallel; A plurality of groups of glue points, each group of glue points is arranged along the arrangement direction of the auxiliary grid, the middle of the glue points has a supporting groove for supporting the welding strip, the bottom of the supporting groove is through in a direction perpendicular to the battery sheet, or the bottom thickness of the supporting groove is not greater than the height of the auxiliary grid; The welding strip is located in a supporting groove of a group of glue points, and the welding strip is in contact with the auxiliary grid.

2. The busbar-free battery assembly according to claim 1, characterized in that: The glue dots include two sub-glue dots spaced apart along the extending direction of the secondary grid lines, and the supporting groove is formed between the two sub-glue dots.

3. The busbar-free battery assembly according to claim 1, characterized in that: The cross section of the supporting groove matches the cross section of the welding strip.

4. The busbar-free battery assembly according to claim 3, characterized in that: The glue dots are located between adjacent sub-grids.

5. A dispensing component, characterized in that: include: A screen, the screen comprising a plurality of scraping grooves arranged in parallel, and a plurality of glue dispensing holes arranged at intervals along the extending direction of the scraping grooves, wherein the glue dispensing holes comprise two sub-holes arranged at intervals along the width direction of the scraping grooves, and the sub-holes are connected to the scraping grooves; The scraper is used to scrape off the glue coated in the scraping groove.

6. The dispensing assembly according to claim 5, characterized in that: Along the width direction of the scraping groove, the size of the bottom of the scraping groove is smaller than the size of the top of the scraping groove.

7. The dispensing assembly according to claim 6, characterized in that: The cross section of the scraping groove is arc-shaped or polygonal; or, the cross section of the scraping groove is consistent with at least a part of the cross section of the welding strip to be fixed.

8. The dispensing assembly according to any one of claims 5 to 7, characterized in that: The sub-holes overlap with the edges of both sides of the scraping groove in the width direction, and the bottom wall of the scraping groove is located between the sub-holes.

9. The dispensing assembly according to any one of claims 5 to 7, characterized in that: The two sub-holes are symmetrically arranged along the central axis of the scraping groove.

10. The dispensing assembly according to claim 5, characterized in that: The scraper comprises a scraper plate and a scraper block located at the bottom of the scraper plate and extending into the scraper groove. The size of the scraper block is not greater than the size of the scraper groove.

11. The glue dispensing assembly according to claim 10, characterized in that: The cross section of the scraping block is consistent with the cross section of the scraping groove.

12. A method for preparing a busbar-free battery assembly, characterized in that: The glue dispensing assembly described in any one of claims 5 to 11 is used to form glue dots on the surface of the busbar-free battery cell.

13. The method for preparing a busbar-free battery assembly according to claim 12, characterized in that: The steps include: The screen is laid on the surface of the busbar-free solar cell, the scraping groove extends along the arrangement direction of a plurality of sub-grids of the busbar-free solar cell, and the glue dispensing holes are staggered with the sub-grids; Applying glue in the scraping groove; The glue applied in the scraping groove is scraped off by a scraper to form glue dots at the glue dispensing holes.

14. The method for preparing a busbar-free battery assembly according to claim 13, characterized in that: The glue dispensing hole is located between two adjacent secondary grid lines, and the glue dispensing hole is arranged close to one of the secondary grid lines.

15. The method for preparing a busbar-free battery assembly according to claim 13, characterized in that: The scraper comprises a scraper plate and a scraper block located at the bottom of the scraper plate and extending into the scraper groove. The scraper block moves along the extending direction of the scraper groove to scrape off the glue.

16. The method for preparing a busbar-free battery assembly according to claim 12, characterized in that: The process of forming a glue point thickness on the surface of the busbar-free solar cell also includes the following steps: Fixing the welding strip on the busbar-free solar cell through the glue point, the welding strip connecting the front side of a busbar-free solar cell with the back side of an adjacent busbar-free solar cell; Applying pressure, the welding strip contacts the secondary grid of the battery cell without main grid; Heat treatment, the heat treatment temperature is 5°C to 30°C higher than the melting point of the welding strip, the time is 10s to 40s, so that an alloy is formed between the welding strip and the auxiliary grid.

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