Coating equipment

Abstract

The utility model relates to coating equipment. The coating equipment comprises a body part, an air inlet part, a carrier and a heating part, the body part comprises an inner shell and an outer shell, the inner shell is located in the outer shell, an inner cavity of the inner shell forms an inner cavity, and an outer cavity is formed between the inner shell and the outer shell; the gas inlet part is used for introducing process gas into the inner cavity, and the heating part is used for heating the inner cavity; the carrier is arranged in the inner cavity, the carrier is provided with a mounting cavity and a first opening, the mounting cavity is used for mounting stacked substrates, the to-be-coated surface of each substrate can be exposed from the first opening, and the heating part comprises a plurality of heating units arranged on the peripheral side of the first opening. The coating equipment can be used for coating and passivating the cutting surface of a substrate such as a battery piece, and can also be used for annealing the cutting surface, so that the passivation effect is ensured, the overall structure is simplified, the cost is reduced, and the production efficiency can be effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of solar cell processing, and in particular to a coating device. Background Art

[0002] It is a very common method to cut a whole battery into small pieces. Generally, laser non-destructive cutting is used to cut a whole finished battery into small pieces. The cut surface forms a non-passivated surface. The non-passivated surface has many defects and the surface charge recombination is very serious, which affects the life of minority carriers and thus affects the efficiency of the battery, and then affects the power generation of the component.

[0003] To solve the problem of defects in cutting battery cells, the main method at present is to passivate the cut surface of the battery cell by coating. After coating, in order to ensure the passivation effect, the edge of the battery cell must be further annealed and the substrate is moved to an annealing furnace for annealing. The operation is relatively cumbersome and seriously affects production efficiency. Utility Model Content

[0004] The purpose of this application is to provide a coating device that can be used to perform coating and passivation on the cut surfaces of substrates such as battery cells, and can also perform annealing treatment on them to ensure the passivation effect, simplify the overall structure, reduce costs and effectively improve production efficiency.

[0005] In order to solve the above technical problems, the present application provides a coating device, including a main body, an air inlet, a carrier and a heating part; the main body includes an inner shell and an outer shell, the inner shell is located in the outer shell, the inner cavity of the inner shell forms an inner cavity, and an outer cavity is formed between the inner shell and the outer shell; the air inlet is used to introduce process gas into the inner cavity, and the heating part is used to heat the inner cavity; the carrier is arranged in the inner cavity, and the carrier is provided with an installation cavity and a first opening, the installation cavity is used to install stacked substrates, and the surface to be coated of each substrate can be exposed by the first opening, and the heating part includes a plurality of heating units arranged around the first opening.

[0006] Optionally, the heating portion further includes a heating plate arranged along the circumference of the inner shell.

[0007] Optionally, the heating plate is arranged in the outer cavity.

[0008] Optionally, the heating portion further comprises heating elements arranged at the air inlet end and the air outlet end of the main body portion.

[0009] Optionally, at most two of the carriers are arranged in the inner cavity along the airflow direction.

[0010] Optionally, the carrier is further provided with a pressing portion, and the pressing portion can press each of the substrates along the stacking direction.

[0011] Optionally, a second opening is formed on a side wall of the installation cavity facing the stacking direction; the carrier further comprises a pressure cover, which is disposed at the second opening and fits and presses the substrate, and the pressure cover forms the pressing portion.

[0012] Optionally, the stacking direction is a height direction, the second opening is opened on a top wall of the mounting cavity, and the pressure cover can press the substrate downward under the action of gravity.

[0013] Optionally, gaskets are provided between the pressure cover and the substrate, and between a side wall of the installation cavity away from the second opening and the substrate, respectively, and the gaskets can cover the surface of the substrate.

[0014] Optionally, the circumferential side wall of the installation cavity can fit with the circumferential surface of the substrate to shield the circumferential surface of the substrate.

[0015] Optionally, it also includes a furnace door and a pump body; the main body is provided with an air inlet end and an air outlet end, the furnace door is arranged at the air inlet end, and can seal the outer cavity, and form a vacuum chamber together with the outer cavity; the air inlet part includes a spray plate, the spray plate can be sealed with the air inlet end of the inner cavity, and is used to introduce process gas into the inner cavity; the pump body is arranged at the air outlet end, and is used to provide power for the gas circulation in the inner cavity.

[0016] Optionally, a telescopic mechanism is further provided between the spray plate and the furnace door, and when the furnace door blocks the outer cavity, the telescopic mechanism can be deformed to allow the spray plate to block the air inlet end of the inner cavity.

[0017] Optionally, the distance between the first opening and the spray plate is 6 mm-30 mm.

[0018] Compared with the prior art, the coating equipment provided by the present application has the following technical effects:

[0019] The heating part includes a plurality of heating units arranged in the inner cavity, each heating unit is arranged close to the first opening and arranged on the peripheral side of the first opening, the distance between the heating unit and the surface to be coated of the substrate (or the surface to be coated formed after cutting) is relatively close, and the heating unit is used to quickly heat the substrate from the first opening.

[0020] After the coating passivation is completed, in order to achieve a better passivation effect on the edge of the battery cell, the substrate can be annealed. The annealing process requires a relatively high temperature. At this time, the coating surface of the substrate can be auxiliary heated by multiple heating units close to the first opening. Since the distance between the heating unit and the coating surface of the substrate is relatively close, the heat transfer rate is relatively fast, and only the area near the coating surface can be heated. There is no need to heat all the spaces inside the inner cavity, which reduces the heating range, has a fast heating rate and a good heating effect. While meeting the annealing temperature requirements of the coating surface, it can reduce power loss and improve economic efficiency. At the same time, it can also avoid the situation where the life of the inner shell is reduced due to the overall temperature in the inner cavity rising to the annealing process temperature.

[0021] The heating unit can locally and quickly perform auxiliary heating on the coating surface to ensure that the coating surface can reach the annealing process temperature. Therefore, the coating equipment can directly carry out the annealing process after the substrate completes the passivation process in the same cavity, without the need for additional annealing or heating furnaces, thereby further simplifying the process and equipment, effectively improving production progress and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of a coating device provided in an embodiment of the present application;

[0023] Figure 2 yes Figure 1 A schematic diagram of the internal structure of the main body portion facing the air inlet end;

[0024] Figure 3 yes Figure 1 Schematic diagram of the structure of the medium vehicle;

[0025] Figure 4 It is a schematic diagram of the structure when a carrier is arranged in the axial direction in the inner cavity;

[0026] Figure 5 yes Figure 4 Left view of

[0027] Figure 6 It is a schematic diagram of the structure when two carriers are arranged axially in the inner cavity;

[0028] Figure 7 It is a schematic diagram of the structure when two rows of carriers are arranged in the inner cavity along the axial direction and the height direction respectively;

[0029] Figure 8 yes Figure 7 Left view of .

[0030] Attached Figure 1-Figure 8 In the figure, the reference numerals are described as follows:

[0031] 1 main body, 11 outer shell, 12 inner shell, 13 outer cavity, 14 inner cavity, 15 air inlet end, 16 air outlet end;

[0032] 2 air intake part, 21 gas cabinet, 22 spray plate;

[0033] 3 carrier, 31 gland, 32 gasket;

[0034] 4 Heating unit;

[0035] 5 second heating unit;

[0036] 6 furnace door;

[0037] 7. Heating element;

[0038] 8 telescopic mechanism;

[0039] 9 substrates. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the technical solution of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0041] The embodiment of the present application provides a coating device that can be used to perform coating passivation on the cut surface of a battery cell, so as to passivate the edge of the battery cell.

[0042] like Figure 1 As shown, the coating equipment includes a main body 1, a furnace door 6, an air intake part 2, a carrier 3, a heating part, a pump body (not shown in the figure), etc.

[0043] Among them, Figure 1 As shown, the main body 1 includes an outer shell 11 and an inner shell 12 . The inner shell 12 is located inside the outer shell 11 and forms an inner cavity 14 inside the inner shell 12 . An outer cavity 13 is formed between the inner shell 12 and the outer shell 11 .

[0044] The carrier 3 is located in the inner cavity 14, and the carrier 3 is provided with an installation cavity, and the side wall of the installation cavity is provided with a first opening. There are multiple substrates 9 (such as solar cells) stacked in the installation cavity, and the surface to be coated (such as the cutting surface) of each substrate 9 can be exposed from the first opening, and the rest of the surface of the substrate 9 is blocked.

[0045] The main body 1 includes an air inlet end 15 and an air outlet end 16. The furnace door 6 and the air inlet 2 are arranged at the air inlet end 15 of the main body 1. The furnace door 6 can block the end of the outer cavity 13. The air inlet 2 includes a gas cabinet 21 and a spray plate 22. The spray plate 22 is arranged on the side of the furnace door 6 facing the main body 1. A telescopic mechanism 8 is also arranged between the air inlet 2 and the furnace door 6. When the furnace door 6 blocks the outer cavity 13, the telescopic mechanism 8 can be deformed to make the spray plate 22 block the end of the inner cavity 14.

[0046] During the coating process, the heating unit heats the inner cavity 14, and the outer cavity 13 is first evacuated and then filled with nitrogen. The gas cabinet 21 can spray process gas into the inner cavity 14 through the spray plate 22. The process gas coats the surface of the substrate 9 to be coated when passing through the carrier 3, and then the excess process gas and reaction products are discharged from the exhaust end under the power provided by the pump body. The direction of the airflow in the inner cavity 14 is Figure 1 As shown by the middle arrow, the air flows from the air inlet end 15 to the air outlet end 16 .

[0047] The process gas introduced into the inner cavity 14 by the gas cabinet 21 through the spray plate 22 may include two gases, such as carrier gas nitrogen and reaction gas oxygen. After being introduced into the inner cavity 14 at the same time, the nitrogen and oxygen are fully mixed in the inner cavity 14 to dilute the oxygen to the required concentration. Therefore, in this embodiment, the distance between the first opening of the carrier and the spray plate 22 is preferably set to 6mm-30mm. Such a setting can avoid the distance between the surface to be plated and the spray plate 22 being too small, resulting in uneven mixing of the carrier gas and the reaction gas in the process gas, affecting the uniformity of the coating. At the same time, it can also avoid the situation where the length of the main body 1 is too long due to the large distance between the surface to be plated and the spray plate 22, which is conducive to miniaturization of the equipment.

[0048] The heating part specifically includes a first heating part and a second heating part, wherein the first heating part is arranged in the inner cavity 14, and includes a plurality of heating units 4, each of which is arranged near the first opening and arranged on the peripheral side of the first opening (such as Figure 2 As shown in FIG. 1 , the distance between the heating unit 4 and the surface to be coated (or the coated surface formed after coating) of the substrate 9 is relatively close, and the heating unit 4 is used to quickly heat the substrate 9. Specifically, the heating unit 4 can use a heating element with a high temperature response speed and temperature control accuracy, such as an infrared lamp, and is not specifically limited here. The second heating part 5 includes a heating plate arranged along the circumference of the inner shell 12.

[0049] Specifically, during the coating process, the inner cavity 14 can be heated only by the heating plate of the second heating unit 5 , so that the inner cavity 14 has good temperature uniformity to ensure the coating effect.

[0050] After the coating passivation is completed, in order to achieve a better passivation effect on the edge of the battery cell, the coated surface of the substrate 9 can be annealed. The temperature required for the annealing treatment is relatively high. At this time, the coated surface of the substrate 9 can be auxiliary heated by multiple heating units 4 close to the first opening. Since the distance between the heating unit 4 and the coated surface of the substrate 9 is relatively close, the heat transfer rate is relatively fast, and only the area near the coated surface can be heated. There is no need to heat all the spaces inside the inner cavity 14, which reduces the heating range, has a fast heating rate and a good heating effect. While meeting the annealing temperature requirements of the coated surface, it can reduce power loss and improve economy. At the same time, it can also avoid the situation where the temperature in the inner cavity 14 rises to the annealing process temperature as a whole, resulting in a reduction in the life of the inner shell 12.

[0051] By heating the heating plate of the second heating unit 5, a uniform temperature field can be formed in the inner cavity 14 to ensure the uniformity of the coating. The first heating unit can quickly and locally perform auxiliary heating on the coating surface to ensure that the coating surface can reach the annealing process temperature. Therefore, the coating equipment can realize the passivation process and annealing process of the substrate 9 in the same cavity without the need for an additional annealing or heating furnace, thereby further simplifying the process and equipment, effectively improving production progress and reducing costs.

[0052] Of course, in this embodiment, the second heating unit 5 may not be provided, and the substrate 9 may be heated by the heating units 4 of the first heating unit during the coating process and the subsequent annealing process. The provision of the second heating unit 5 can form a temperature field with good uniformity in the inner cavity 14 to ensure the coating effect.

[0053] like Figure 1 As shown, the heating portion further includes heating elements 7 (specifically, heating plates) disposed at both axial ends of the main body 1 . Such an arrangement can further ensure the uniformity of the temperature field in the inner cavity 14 .

[0054] In this embodiment, the second heating unit 5 can be as follows Figure 1 and Figure 2 As shown, the second heating unit 5 can be arranged in the outer cavity 13, or the second heating unit 5 can be arranged in the inner cavity. When the second heating unit 5 is arranged in the outer cavity 13, it can reduce the space occupied in the inner cavity 14, so that when the space in the inner cavity 14 is fixed, more carriers 3 can be arranged as much as possible, which is conducive to increasing the processing volume and thus improving the production capacity when the overall volume of the coating equipment is fixed.

[0055] Furthermore, when the second heating part 5 is disposed in the outer cavity 13, it is also disposed close to one side of the inner shell 12 to ensure heat transfer efficiency.

[0056] There are at most two carriers 3 arranged in the inner cavity 14 along the airflow direction, which may be as follows: Figure 4A carrier 3 shown in FIG. 1 may also be Figure 6 and Figure 7 The two vehicles 3 shown, Figure 4 and Figure 5 In the embodiment, only one carrier 3 is arranged in the inner cavity 14. Figure 6 In the embodiment, only two carriers 3 are arranged in the inner cavity 14, and the two carriers 3 are arranged side by side along the airflow direction, or the two carriers 3 can also be arranged side by side along the lateral direction or the height direction, wherein the lateral direction refers to the direction of the airflow. Figure 5 and Figure 8 The left and right directions in the figure are as follows: Figure 5 and Figure 8 The up and down directions in . Figure 7 and Figure 8 As shown, eight carriers 3 are arranged in the inner cavity 14 .

[0057] There may or may not be a gap between two adjacent carriers 3, as long as the surface of the substrate 9 to be coated is not blocked by other carriers 3. In this embodiment, there is no restriction on the number of carriers 3 arranged in the lateral and height directions. When the number of carriers 3 arranged in the airflow direction does not exceed two, the overall length of the main body 1 can be reduced.

[0058] The main body 1 adopts a tubular furnace, and at most two carriers 3 are arranged inside the furnace body along the airflow direction, so that the volume of the tubular furnace in the length direction is small, the space occupied is small, and the cost is low. In addition, the small space inside the furnace allows the internal flow field and temperature field to be better controlled, which can effectively improve the uniformity of film thickness.

[0059] Furthermore, since the space inside the inner cavity 14 is relatively small, the temperature inside the inner cavity 14 can be quickly increased, thereby improving the heating efficiency and further increasing the production capacity.

[0060] Each mounting cavity of the carrier 3 can be equipped with 500-1000 stacked substrates 9. The number of substrates 9 in each carrier 3 can be determined according to the size of the mounting cavity and the thickness of the substrate 9. Figure 8 As shown, when eight carriers 3 are arranged in the inner cavity 14, the coating equipment can achieve a single-tube production capacity of 4000-8000 pieces, with a large number of wafers. Moreover, compared with the complex structure of existing plate-type equipment, this solution has a greater cost advantage and is more suitable for photovoltaic industrialization.

[0061] In this embodiment, there is no restriction on the arrangement of the carrier 3 in the inner cavity 14. The axis of the first opening of the carrier 3 can be arranged perpendicular to the spray plate 22. At this time, the surface of the substrate 9 to be coated is arranged parallel to the spray plate 22. At this time, the first opening can be set toward the spray plate 22 or away from the side of the spray plate 22. Alternatively, the axis of the first opening can be arranged parallel to the spray plate 22. At this time, the surface of the substrate 9 to be coated is parallel to the airflow direction.

[0062] Preferably, the first opening is directed toward the air inlet 15, the air outlet 16, upward, or toward both lateral sides of the carrier 3. That is, the first outlet of the carrier 3 is preferably not set to face downward to avoid the substrate 9 from falling.

[0063] The substrates 9 are stacked in sequence in the mounting cavity of the carrier 3. The carrier 3 also includes a clamping portion, which can clamp the substrates 9 along the stacking direction of the substrates 9 to ensure that the substrates 9 are tightly fitted to each other and reduce the gaps between the substrates 9 for gas to enter to improve the winding degree.

[0064] The mounting cavity of the carrier 3 is also provided with a second opening, and the second opening is used for mounting the substrate 9. Figure 3 As shown, the carrier 3 also includes a pressure cover 31, which is arranged at the second opening and can fit and press the adjacent substrates 9, so that each substrate 9 is pressed toward the side wall of the installation cavity away from the second opening in the stacking direction, ensuring the fit between two adjacent substrates 9, and the pressure cover 31 forms the above-mentioned pressing portion.

[0065] Of course, in this embodiment, the specific structure of the pressing part is not limited. For example, the pressing part can also be set to include two pressing members, both of which are arranged in the installation cavity and can press the stacked substrates 9 from both sides along the stacking direction. The pressing part is formed by the pressure cover 31, which can simplify the specific structure of the pressing part and facilitate the installation operation.

[0066] Further, such as Figure 3 As shown, a gasket 32 ​​is provided between the pressure cover 31 and the substrate 9, and a gasket 32 ​​is also provided between the side wall of the mounting cavity away from the second opening and the substrate 9. The gasket 32 ​​can cover the surface of the substrate 9 to prevent the deformation of the substrate 9 during compression, and at the same time, can also shield the surface of the substrate 9 to prevent the surface from being coated. The gasket 32 ​​requires a material with a smooth surface that can fit well with the substrate 9, and there is no specific limitation.

[0067] When the stacking direction is along the height direction and the second opening is arranged at the top of the carrier 3, the pressure cover 31 can squeeze the substrate 9 from the top. At this time, the pressure cover 31 can squeeze the substrate 9 by its own gravity or by an external force such as a spring.

[0068] The side wall of the mounting cavity is only provided with a first opening and a second opening, wherein the first opening is used to expose the surface to be coated of the substrate 9 to facilitate coating and annealing, and the second opening is used to mount the substrate 9. The remaining side walls of the mounting cavity are blocked to prevent the remaining surfaces of the substrate 9 from being exposed, thereby preventing the remaining surfaces of the substrate 9 from being coated.

[0069] That is to say, the circumferential side wall of the mounting cavity (a first opening is provided on one side of the circumferential side wall) can fit with the circumferential surface of the substrate 9 and shield the circumferential surface of the substrate 9 to prevent the circumferential surface of the substrate 9 other than the surface to be coated from being coated.

[0070] Of course, in this embodiment, the other five sides of the substrate 9 except the surface to be coated can also be shielded by an additional shielding member. When the surface of the substrate 9 is shielded by the inner wall of the mounting cavity of the carrier 3 and the gasket 32, the overall structure can be simplified and the installation operation can be facilitated.

[0071] When using the atomic layer deposition process (ALD) for deposition, the pulse gas intake mode is A / B / A / B. Taking the preparation of Al2O3 coating as an example, the A process gas is trimethylaluminum, the B process gas is H2O, the A pulse intake time is 1s-10s, the B pulse intake time is 1s-10s, and the A and B process gases are switched between using an inert gas such as nitrogen for purging, and the purging time is 8s-12s. In the above manner, the winding degree of the substrate 9 can be controlled within 0-2mm at the edge.

[0072] The structure and arrangement of the carrier 3 provided in the embodiment of the present application, in combination with appropriate pulse time of process gas and the position of the carrier 3 relative to the shower plate 22 , can effectively improve the winding problem of the substrate 9 .

[0073] The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A coating device, characterized in that: It comprises a main body (1), an air intake portion (2), a carrier (3) and a heating portion; The main body (1) comprises an inner shell (12) and an outer shell (11), the inner shell (12) is located inside the outer shell (11), the inner cavity of the inner shell (12) forms an inner cavity (14), and an outer cavity (13) is formed between the inner shell (12) and the outer shell (11); The gas inlet portion (2) is used to introduce process gas into the inner cavity (14), and the heating portion is used to heat the inner cavity (14); The carrier (3) is arranged in the inner cavity (14), and is provided with a mounting cavity and a first opening. The mounting cavity is used to mount the stacked substrates (9), and the surface to be coated of each substrate (9) can be exposed through the first opening. The heating portion comprises a plurality of heating units (4) arranged around the first opening.

2. The coating device according to claim 1, characterized in that: The heating portion further comprises a heating plate arranged along the circumference of the inner shell (12).

3. The coating device according to claim 2, characterized in that: The heating plate is arranged in the outer cavity (13).

4. The coating device according to claim 2, characterized in that: The heating portion further comprises a heating element (7) arranged at an air inlet end (15) and an air outlet end (16) of the main body portion (1).

5. The coating device according to any one of claims 1 to 4, characterized in that: In the inner cavity (14), at most two carriers (3) are arranged along the airflow direction.

6. The coating device according to any one of claims 1 to 4, characterized in that: The carrier (3) is also provided with a pressing portion, and the pressing portion is capable of pressing each substrate (9) along the stacking direction.

7. The coating device according to claim 6, characterized in that: A second opening is formed on a side wall of the installation cavity facing the stacking direction; The carrier (3) further comprises a pressure cover (31), wherein the pressure cover (31) is arranged at the second opening and fits and presses the substrate (9), and the pressure cover (31) forms the pressing portion.

8. The coating device according to claim 7, characterized in that: The stacking direction is the height direction, the second opening is opened on the top wall of the installation cavity, and the pressing cover (31) can press the substrate (9) downwards under the action of gravity.

9. The coating device according to claim 7, characterized in that: Gaskets (32) are provided between the pressure cover (31) and the substrate (9), and between a side wall of the installation cavity away from the second opening and the substrate (9), respectively, and the gaskets (32) are capable of covering the surface of the substrate (9).

10. The coating device according to claim 9, characterized in that: The circumferential side wall of the installation cavity can fit with the circumferential surface of the substrate (9) to shield the circumferential surface of the substrate (9).

11. The coating device according to any one of claims 1 to 4, characterized in that: It also includes a furnace door (6) and a pump body; The main body (1) is provided with an air inlet end (15) and an air outlet end (16); the furnace door (6) is provided at the air inlet end (15) and is capable of sealing the outer cavity (13) and enclosing the outer cavity (13) to form a vacuum chamber; The air inlet portion (2) comprises a spray plate (22), the spray plate (22) being capable of sealing with the air inlet end (15) of the inner cavity (14) and being used for introducing process gas into the inner cavity (14); The pump body is arranged at the gas outlet end (16) and is used to provide power for the gas circulation in the inner cavity (14).

12. The coating device according to claim 11, characterized in that: A telescopic mechanism (8) is also provided between the spray plate (22) and the furnace door (6); when the furnace door (6) is in a state of sealing the outer cavity (13), the telescopic mechanism (8) can be deformed to allow the spray plate (22) to seal the air inlet end (15) of the inner cavity (14).

13. The coating device according to claim 11, characterized in that: The distance between the first opening and the spray plate (22) is 6 mm to 30 mm.

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