Battery piece grid line developing preparation process and production equipment

Abstract

The invention provides a battery piece grid line developing preparation process which comprises the following steps: sequentially performing developing operation on an exposed battery piece in different developing tanks, and washing off unexposed parts to obtain an opening area where a thin grid line in the battery piece is located; and cleaning the developed battery piece, and exposing the to-be-metalized region. The battery piece grid line developing preparation technology is mainly used for carrying out combined type developing operation on a horizontally-placed battery piece, developing cleaning in different control modes can be selected based on the requirements of different battery pieces, the technical problem that imaging obstacles are likely to occur in the developing technology can be effectively solved, and the developing efficiency is improved. The fine grid lines with clear patterns and accurate lines can be obtained, the bottoms of the fine grid lines are developed cleanly, and the overall consistency is good; the preparation process not only can ensure the developing quality and improve the developing effect, but also can ensure the photoelectric conversion rate and the output power of the battery piece. The invention also provides production equipment adapted to the development preparation process.

Description

Technical Field

[0001] This application belongs to the technical field of solar cell grid line processing, and in particular relates to a developing preparation process for cell grid lines and a production device adapted to the developing preparation process. Background Art

[0002] The grid lines of solar cells are an important part of the front metal electrodes of solar cells. Their main function is to collect and transport photo-generated carriers, thereby realizing the conversion of solar energy into electrical energy. As a key material affecting the conductivity of solar cells, they directly determine the photoelectric conversion efficiency of solar cells. Among them, the grid lines include main grid lines and fine grid lines. The fine grid lines are mainly used to increase the surface area of the battery to improve the light absorption capacity and conversion efficiency of the battery. In this way, more solar energy is converted into electrical energy, and since the current output capacity of the battery is increased, the power generation efficiency of the battery is also correspondingly improved.

[0003] The smaller the width of the fine grid line, the more it can increase the surface area of the battery. However, in the developing process for preparing it, patterning obstacles are likely to occur. Existing developing processes are mostly spray-type, which can only spray the developing solution on the photosensitive layer, that is, the oil film surface, so that the developing solution decomposes the unexposed area from the oil film surface to the bottom of the oil film. However, when the opening line width is less than 20 um or below, a large amount and sufficient decomposition time are required to allow the developing solution to contact the entire oil film for decomposition. Due to the extremely small line width, the existing spray-type developing process cannot provide sufficient developing solution, and thus cannot completely decompose the unexposed area from the oil film surface, sidewalls to the bottom, which will interrupt the reaction effect of the oil film decomposition, resulting in poor developing effect, making it impossible to form a broken grid by copper plating subsequently, and the quality of the fine grid lines is unstable, directly affecting the photoelectric conversion efficiency and output power of the solar cells. Summary of the Invention

[0004] This application provides a developing preparation process for cell grid lines and a production device adapted to the developing preparation process, which is particularly suitable for performing a combined developing operation on horizontally placed solar cells to solve the technical problem in the prior art that due to patterning obstacles easily occurring in the developing process, the developing solution cannot completely contact the oil film on the surface of the solar cell during development, resulting in the interruption of the reaction effect of the oil film decomposition, thus leading to poor developing effect and unstable quality of the fine grid lines.

[0005] To solve at least one of the above technical problems, the technical solution adopted in this application is:

[0006] A developing preparation process for cell grid lines, the steps including:

[0007] Performing an immersion and / or open developing operation on the exposed solar cell to wash away the unexposed part to obtain the opening area where the fine grid lines in the solar cell are located;

[0008] The developed solar cell is cleaned to expose the metallization area to be processed.

[0009] Furthermore, the immersion and / or open development operations are performed on the horizontally placed solar cell.

[0010] Preferably, when performing the immersion development operation on the solar cell, the solar cell is controlled to be immersed in the developer solution on one side or both sides to perform the development process on one side or both sides of the solar cell.

[0011] Preferably, when performing the open development operation on the solar cell, the developer solution is sprayed on both sides of the solar cell, wherein the spraying pressure of the developer solution is controlled within the range of 0.5 - 3.5 kg / cm 2 .

[0012] Furthermore, the developer solution in all the development tanks is an alkaline chemical solution.

[0013] Preferably, the alkaline chemical solution is sodium hydroxide or potassium hydroxide.

[0014] Furthermore, when the alkaline chemical solution is sodium hydroxide or potassium hydroxide, its volume concentration ranges from 0.01% to 5%.

[0015] Furthermore, the temperature range of all the developer solutions is 10 - 50°C.

[0016] Furthermore, the cleaning of the developed solar cell includes pure water cleaning of the surface of the solar cell, and then drying the cleaned solar cell.

[0017] Preferably, before performing the immersion and / or open development operations on the exposed solar cell, the step of obtaining the exposed solar cell is further included.

[0018] A solar cell grid line development production device, applicable to the preparation process as described above, has a development unit and a cleaning unit. Among them, the development unit is equipped with a development tank, and the development unit is arranged on the side close to the solar cell feeding port; the cleaning unit is arranged on the side close to the solar cell discharging port.

[0019] Furthermore, the development unit includes an immersion development tank and / or an open development tank, and a transmission line for driving the horizontal movement of the solar cell is provided in all the development tanks.

[0020] Preferably, in the development unit, at least one immersion development tank is provided.

[0021] Preferably, at least one open development tank is further included in the immersion development tank.

[0022] Preferably, in the immersion developing tank, both sides of the cell are completely immersed in the developing solution in the tank or one side of the cell is immersed in the developing solution in the tank.

[0023] Furthermore, a transmission line for transporting the cell is also provided in the developing unit, which is horizontally arranged in the developing unit and the cleaning unit;

[0024] Preferably, the transmission line includes a number of rollers arranged in pairs, and the rollers clamp the cell and drive the cell to move forward.

[0025] Furthermore, a number of spray heads for spraying the liquid medicine are also provided in the developing unit. The spray heads are respectively arranged on the upper and lower sides of the cell and spray towards the surface of the cell;

[0026] The spray head is configured as a fixed structure or a swinging structure;

[0027] Preferably, the cleaning unit further includes a cleaning tank; a drying oven is further provided after the cleaning tank;

[0028] Preferably, an ultrasonic device is also provided in the immersion developing tank.

[0029] A cell grid line developing preparation process designed by the present application is mainly used for performing a composite developing operation on a horizontally placed cell. Different control methods of developing and cleaning can be selected based on the requirements of different cells, which can effectively solve the technical problem of easy occurrence of patterning obstacles in the developing process. Not only can fine grid lines with clear graphics and precise lines be obtained, but also the bottom of the fine grid lines is developed cleanly and the overall consistency is good; this preparation process can not only ensure the developing quality and improve the developing effect, but also ensure the photoelectric conversion efficiency and output power of the cell. The present application also proposes a production device adapted to this developing preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a flowchart of a cell grid line developing preparation process according to an embodiment of the present application;

[0031] Figure 2 is a schematic diagram of a production device for double-sided immersion developing according to an embodiment of the present application;

[0032] Figure 3 is a schematic diagram of the structure of one of the developing tanks according to an embodiment of the present application;

[0033] Figure 4 is a schematic diagram of a double-sided immersion developing tank according to an embodiment of the present application;

[0034] Figure 5 is a simplified diagram of a composite developing tank according to an embodiment of the present application;

[0035] Figure 6 It is a schematic structural diagram of a solar cell after double-sided development according to an embodiment of the present application;

[0036] Figure 7 It is a schematic structural diagram of a solar cell after single-sided development according to an embodiment of the present application.

[0037] In the figure:

[0038] 10. Development unit 11. Immersion development tank 12. Open development tank

[0039] 20. Cleaning unit 21. Cleaning tank 22. Drying oven

[0040] 30. Solar cell 31. Opening area 32. Metallization area

[0041] 40. Transmission line 50. Sprayer Specific embodiments

[0042] The present application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] This embodiment provides a preparation process for developing grid lines of a solar cell. As Figure 1 shown, the main development operation is performed on a horizontally placed solar cell, and the steps include:

[0044] S1: Obtain an exposed solar cell.

[0045] Before development, the solar cell needs to be exposed. Specifically, after nitriding the silicon wafer, the metal part needs to be exposed. First, a mask is prepared by photolithography. Then, a photosensitive adhesive layer, i.e., an oil film layer, is coated on the solar cell, and exposure is performed through the corresponding mask to obtain a solar cell with a certain pattern shape (this is common knowledge in the art).

[0046] S2: Perform immersion and / or open development operations on the exposed solar cell to wash away the unexposed part to obtain the opening area where the fine grid lines in the solar cell are located.

[0047] After exposure, the solar cell is placed in the developer to wash away the unexposed part, that is, to remove the photosensitive adhesive layer on the part not irradiated by the exposure light. At the same time, the developer remaining on the surface of the solar cell is cleaned, and only the area covered by the photolithography pattern is retained to obtain a solar cell 30 with an opening area 31 as shown in Figure 6 or Figure 7 in the figure.

[0048] As Figure 2As shown, specifically, during the development process, based on the development sequence of the solar cells, the exposed solar cells 30 placed horizontally are successively subjected to immersion development operations and / or open development operations. That is, for different solar cells 30, a development process suitable for them can be selected.

[0049] As Figure 3 shown, is a schematic structural diagram of one of the development tanks in the development process. It can be seen from the figure that there is a transmission line 40 for clamping and driving the forward movement of the solar cells 30, and spray heads 50 are arranged on the upper and lower sides of the transmission line 40. Among them, along the direction of the transmission line 40, several spray heads 50 are arranged on the moving route of each solar cell 30.

[0050] For solar cells 30 with a fine grid line width not greater than 20 μm, they require immersion development operations. That is, only by controlling the height of the developer in the above-mentioned development tank to completely immerse the surface of the solar cell 30 that needs to be developed and etched in the developer can the development operation of the solar cell 30 be completed. During the immersion development process, there is no need to open the spray heads 50.

[0051] For solar cells 30 with a fine grid line width greater than 20 μm, they can be subjected to open development operations on the solar cells using a development tank as Figure 2 shown, that is, by controlling the spray heads 50 to perform a spraying and wetting operation on the surface of the solar cell 30 to be developed and etched, so as to develop and etch the surface of the solar cell. At this time, the height of the developer in the development tank is lower than the position height of the transmission line 40 or no developer is placed, and the development and wetting of the surface of the solar cell are completed by spraying with the spray heads.

[0052] For solar cells 30 with a fine grid line width greater than 20 μm, a combined development operation can also be performed on the solar cells 30, that is, first perform an immersion development operation and then an open development operation. In the combined development tank, the solar cells 30 are first subjected to an immersion development operation and then an open spraying development operation to complete the development of the solar cells 30.

[0053] In the above-mentioned development operations, whether only performing an immersion development operation on the solar cells 30 in the development tank, or only performing a spraying development operation on the solar cells 30 in the development tank, or performing immersion and spraying development operations on the solar cells successively in two development tanks, the development treatment of the solar cells 30 can be completed. A development operation method suitable for different requirements can be selected. The ultimate goal is to wash away the unexposed parts in the exposed solar cells 30, and finally obtain a fine grid line structure with an opening area 31 in the solar cells 30.

[0054] As Figure 2As shown, for horizontal development, it is necessary to first add the developer into the developing tank and heat the developer so that the developer is kept within a preset temperature range. In this embodiment, the temperature of all developers is 10-50°C. Then, the exposed cell 30 is placed on the transmission line 40 built into the developing tank, and then the cell 30 is subjected to immersion and / or spray development. Driven by the transmission line 40, the cell 30 can be mobile immersed and / or sprayed in the developer, and during the development process, the transmission speed of the transmission line 40 is controlled within the range of 0.5 to 6 m / min.

[0055] In the immersion development operation, the liquid level of the developer is controlled to immerse one or both sides of the battery cell 30 in the developer to perform a development operation on the battery cell.

[0056] The following is an example of immersion development of the surface of a double-sided cell:

[0057] like Figure 4 As shown, both sides of the battery cell 30 are controlled to be immersed in the developer in the developing tank, so that the battery cell 30 is completely immersed in the developer, so that the developer can completely contact the photosensitive layer on the surface of the battery cell 30, that is, the oil film, so that the developer decomposes the unexposed area from the surface of the oil film to the bottom of the oil film. After the battery cell 30 is completely immersed in the developer, the developer completely surrounds the oil film, and there is also enough time for the reaction decomposition, so that the unexposed area can be completely decomposed from the surface of the oil film, the side wall to the bottom, and the fine grid line groove with a precise and clear opening line width of no more than 20um is obtained. Thereby, the risk of interrupting the oil film decomposition reaction caused by the first development operation can be avoided, so that the initial development effect can be guaranteed, and it can also be ensured that copper is easily plated in the opening area 31 later to form a complete fine grid line, which makes the quality of the fine grid line unstable, directly affecting the photoelectric conversion rate and output power of the battery cell. Correspondingly, the structure of the obtained battery cell 30 is as follows Figure 6 shown.

[0058] Another method of performing immersion development on the surface of a single-sided cell (illustration omitted) is as follows: Figure 4 The biggest difference is that the side to be developed and etched is immersed in the developer in the tank facing downward, and the side not to be developed and etched is set upward, and only the single side of the battery cell 30 that needs to be developed is controlled to be immersed in the developer in the developing tank. That is, the battery cell 30 to be developed is placed face down on the transmission line 40 in the developing tank, and at the same time, it is ensured that the upper end surface of the battery cell 30 is not immersed in the developer, and only the lower end surface is immersed in the developer. Then control the transmission line 40 to drive the battery cell 30 to perform mobile immersion development treatment in the developer at a speed of 0.5 to 6 m / min, wherein the temperature of the developer is still 20 to 40°C. Correspondingly, the structure of the obtained battery cell 30 is as followsFigure 7 as shown

[0059] In this embodiment, a spray head 50 for spraying is provided in all the developing tanks. However, in the immersion developing tank, the spray head 50 stops working, and the position height of the developing solution in the tank needs to be controlled to adjust its position relative to the etched surface of the battery cell 30, so as to ensure that the surface to be etched can be completely immersed in the developing solution to achieve the etching of the opening area 31 on the surface of the battery cell 30.

[0060] In the open developing operation, as Figure 3 shown, spray heads 50 are arranged above and below the developing tank. By controlling the spraying pressure of the spray heads 50, the developing solution is sprayed onto one or both sides of the battery cell 30 for developing. Among them, the spraying mode of the spray heads 50 can be intermittent spraying or continuous spraying to adjust the wetting effect on the surface of the battery cell 30; the shape of the developing solution sprayed by the spray heads 50 can be water curtain type, water mist type or fan type to adjust the spraying range on the surface of the battery cell 30.

[0061] The spraying of the spray head 50 can be set to swing spraying at an angle, which can swing along the dimension of the battery cell 30 in the transmission direction or along the dimension perpendicular to the transmission direction of the battery cell 30; the range of its swing angle is 5-75°. The swing of the spray head 50 enables the spraying range on the battery cell 30 to fully cover the surface of the battery cell 30 or partially cover the surface of the battery cell 30.

[0062] When performing open developing etching on both sides of the battery cell 30, it is necessary to control the spray heads 50 on the upper and lower sides of the transmission line 40 to spray and wet the upper and lower surfaces of the battery cell 30, and no developing solution is retained in the tank. The sprayed developing solution directly flows away from the bottom of the tank.

[0063] When performing open developing etching on one side of the battery cell 30, if the side to be etched on the battery cell 30 is set upward on the transmission line 40, it is necessary to control the upper spray head 50 to spray the developing solution, while the lower spray head 50 is in the closed state. If the side to be etched on the battery cell 30 is set downward on the transmission line 40, it is necessary to control the lower spray head 50 to spray the developing solution, while the upper spray head 50 is in the closed state.

[0064] For open developing spray etching, regardless of the spraying mode or spraying shape, a battery cell 30 with a fine grid line structure having an opening area 31 as shown in Figure 6 or Figure 7 can be obtained. This is a conventional structure in the art, and the drawings are omitted here. Preferably, when performing open developing operation on the battery cell 30, the spraying pressure range of the spray head for spraying the developing solution is 0.5-3.5 kg / cm 2 .

[0065] Further, in order to improve the development effect, an ultrasonic device is also provided in all immersion development tanks.

[0066] As Figure 5 shown, along the transmission direction, a compound development operation is sequentially performed on the battery cell 30, that is, both the upper and lower surfaces of the battery cell 30 are subjected to double-sided immersion development and double-sided open development. This compound development method is more suitable for the operation of battery cells 30 with diverse photosensitive layers. Or, when the batch production is relatively large and the production capacity of single immersion development or single spray development is insufficient, the compound development treatment process can be selected to jointly complete the development operation of the battery cell 30. Of course, along the transmission direction, the compound development operation can be sequentially performed on one side of the battery cell 30, that is, immersion development and open spray development are performed, and the attached drawings are omitted.

[0067] Whether it is immersion development operation, open development operation or compound development operation, the developer in all development tanks is an alkaline chemical solution. The alkaline chemical solution is sodium hydroxide or potassium hydroxide.

[0068] Further, when the alkaline chemical solution is sodium hydroxide or potassium hydroxide, its volume concentration range is 0.01 - 5%.

[0069] Regardless of the type of alkaline chemical solution, the temperature range in all development tanks is 10 - 50 °C.

[0070] S3: Clean the developed battery cell to expose the metallization area to be performed.

[0071] Clean the developed battery cell 30 in the cleaning tank. During the cleaning process, both sides of the battery cell 30 need to be cleaned, which can not only expose the metallization area 32 to be performed, but also remove the residual developer on the surface of the battery cell 30. Among them, the cleaning solution is pure water, and the double sides of the battery cell are spray-cleaned. After cleaning, the water droplets on the surface of the battery cell 30 are dried to obtain a clean and tidy battery cell 30 with fine grid lines of a certain shape.

[0072] A production device for developing grid lines of a battery cell, as Figure 2 shown, is applicable to the above-mentioned preparation process, and has a development unit 10 and a cleaning unit 20. Among them, the development unit 10 is equipped with a development tank, and the development unit 10 is arranged on the side close to the inlet of the battery cell 30; the cleaning unit 20 is arranged on the side close to the outlet of the battery cell 30.

[0073] As Figure 3As shown in the figure, the developing unit 10 includes an immersion developing tank 21 and / or an open developing tank 22, and a transmission line 40 for driving the horizontal movement of the solar cell 30 and a nozzle 50 for spraying liquid medicine are provided in all the developing tanks. Among them, the transmission line 40 is controlled by rollers arranged in alignment, which can clamp the solar cell 30 and drive the solar cell 30 to move forward. Of course, other types of transmission tracks can also be used for control, which is not specifically limited here. The nozzles 50 are arranged corresponding to the upper and lower sides of the solar cell 30 and are all arranged to spray onto the surface of the solar cell 30.

[0074] As Figure 2 shown in the figure, the developing unit 10 includes at least one immersion developing tank 21. For the solar cell 30 with a fine grid line width not greater than 20 μm, only the immersion developing tank 21 is required to perform the developing operation on the solar cell 30. At this time, a certain amount of developing solution is stored in the tank body of all the developing tanks, and by controlling the height of the developing solution in the tank, the surface of the solar cell 30 that needs to be developed and etched is completely immersed in the developing solution. At this time, it is not necessary to turn on the nozzle 50 to work. Only by immersing the horizontally arranged solar cell 30 with the developing solution can the developing operation on the solar cell 30 be completed.

[0075] Furthermore, the developing unit 10 may also include at least one open developing tank 22. For the solar cell 30 with a fine grid line width greater than 20 μm, only the open developing tank 22 is required to perform the developing operation on the solar cell 30. At this time, the developing equipment includes an open developing operation on the solar cell in the developing tank as Figure 3 shown in the figure, that is, only by controlling the nozzle 50 to perform a spraying and wetting operation on the surface of the solar cell 30 to be developed and etched, so as to perform developing and etching on the surface of the solar cell 30. At this time, the height of the developing solution in the developing tank is lower than the position height of the transmission line 40 or no developing solution is placed, and only the surface of the solar cell 30 is developed and wetted by spraying.

[0076] Furthermore, the developing unit 10 includes at least one immersion developing tank 21 and one open developing tank 22, that is, a composite developing device. This composite developing device is mainly applicable to the solar cell 30 with a fine grid line width greater than 20 μm, that is, first perform an immersion developing operation, and then perform an open developing operation. In the composite developing tank, the solar cell 30 is first subjected to an immersion developing operation, and then an open spraying operation is performed on it to complete the developing of the solar cell 30.

[0077] In the developing device of the present application, in all the developing units 10 and the cleaning units 20, the transfer control of the solar cells 30 is carried out through the horizontally arranged transfer line 40. The transfer line 40 is provided with rollers arranged in alignment, and the solar cells 3.0 are clamped by the rollers and driven forward by them. This horizontally arranged structure can avoid the turbulent flow problem that easily occurs when the solar cells need to be carried by a wafer basket in the existing vertical development. Moreover, for the horizontally arranged solar cells, whether in the immersion developing tank 21 or in the open developing tank 22, they are easily completely wetted and covered by the developing solution, so as to quickly and completely remove the etched areas in the solar cells 30.

[0078] For the immersion developing tank 21, the developing tank can perform immersion development on both sides of the solar cell 30, or perform immersion development on one side of the solar cell 30. In the immersion developing tank 21, by controlling the liquid level height of the developing solution, one side or both sides of the solar cell 30 are immersed in the developing solution to perform a developing operation on the solar cell. At this time, the spray head 50 in the tank does not spray the liquid medicine. Control both sides of the solar cell 30 to be immersed in the developing solution in the developing tank, so that the solar cell 30 is completely immersed in the developing solution, so that the developing solution can completely contact the photosensitive layer, that is, the oil film, on the surface of the solar cell 30, and the developing solution decomposes the unexposed area from the surface of the oil film to the bottom of the oil film. After the solar cell 30 is completely immersed in the developing solution, the developing solution completely surrounds the oil film, and there is also enough reaction decomposition time, so that the unexposed area can be completely decomposed from the surface, side wall to the bottom of the oil film, and a fine grid line groove with an opening line width not greater than 20 μm and accurate and clear lines can be obtained. Thus, the risk of interrupting the oil film decomposition reaction during the first developing operation can be avoided, so that the primary developing effect can be ensured, and it can also ensure that copper plating is easy in the opening area 31 subsequently to form a complete fine grid line, making the quality of the fine grid line unstable and directly affecting the photoelectric conversion efficiency and output power of the solar cell. Correspondingly, the structure of the obtained solar cell 30 is as Figure 6 shown

[0079] For the solar cell 30 that needs to be etched on one side, in the immersion developing tank 21, the side that does not need to be developed is set upward, and only the side of the solar cell 30 that needs to be developed is controlled to be immersed in the developing solution in the developing tank (the attached drawing is omitted). That is, the solar cell 30 to be developed is placed face down on the transfer line 40 in the developing tank, and at the same time, it is ensured that the upper end surface of the solar cell 30 is not immersed in the developing solution, and only the lower end surface is immersed in the developing solution. Then control the transfer line 40 to drive the solar cell 30 to perform a mobile immersion developing process in the developing solution at a speed of 0.5 - 6 m / min, where the temperature of the developing solution is still 20 - 40 °C. Correspondingly, the structure of the obtained solar cell 30 is as Figure 7 shown

[0080] In all developing tanks, a spray head 50 for spraying is provided in the inner hopper. However, in an immersion developing tank, the spray head 50 stops working, and it is also necessary to control the position height of the developing solution in the tank to adjust its position relative to the etched surface of the battery cell 30, so as to ensure that the surface to be etched can be completely immersed in the developing solution to achieve the etching of the opening area 31 on the surface of the battery cell 30.

[0081] In an open developing operation, as Figure 3 shown, spray heads 50 are arranged above and below the developing tank. By controlling the spraying pressure of the spray heads 50, the developing solution is sprayed onto one or both sides of the battery cell 30 for developing. Among them, the spraying mode of the spray head 50 can be intermittent spraying or continuous spraying to adjust the wetting effect on the surface of the battery cell 30; the shape of the developing solution sprayed by the spray head 50 can be a water curtain type, a water mist type or a fan type to adjust the spraying range on the surface of the battery cell 30.

[0082] The spraying of the spray head 50 can be set to swing spraying at an angle, which swings along the dimension of the battery cell 30 in the transmission direction or can also swing along the dimension perpendicular to the transmission direction of the battery cell 30; the range of its swinging angle is 5 - 75°. The swinging of the spray head 50 enables the spraying range on the battery cell 30 to fully cover the surface of the battery cell 30 or partially cover the surface of the battery cell 30.

[0083] When performing open developing etching on both sides of the battery cell 30, it is necessary to control the spray heads 50 on the upper and lower sides of the transmission line 40 to spray and wet the upper and lower surfaces of the battery cell 30, and no developing solution is retained in the tank. The sprayed developing solution directly flows away from the bottom of the tank.

[0084] When performing open developing etching on one side of the battery cell 30, if the side to be etched on the battery cell 30 is set upward on the transmission line 40, it is necessary to control the upper spray head 50 to spray the developing solution, while the lower spray head 50 is in a closed state. If the side to be etched on the battery cell 30 is set downward on the transmission line 40, it is necessary to control the lower spray head 50 to spray the developing solution, while the upper spray head 50 is in a closed state.

[0085] For open developing spray etching, no matter what kind of spraying mode or spraying shape, a battery cell 30 with a fine grid line structure having an opening area 31 as Figure 6 or Figure 7 shown can be obtained. This is a conventional structure in the art, and the drawings are omitted here. Preferably, when operating in an open developing tank, the spray pressure range for spraying the developing solution on the surface of the battery cell 30 is 0.5 - 3.5 kg / cm 2 .

[0086] Furthermore, in order to improve the developing effect, an ultrasonic device is also provided in all immersion developing tanks.

[0087] As Figure 5 shown, the developing unit 10 performs composite developing, including at least two developing tanks, one is an immersion developing tank 21 and the other is an open developing tank 22. That is, both the upper and lower surfaces of the cell 30 are subjected to double-sided immersion developing and double-sided open developing. These two composite developing methods are more suitable for the operation of cells 30 with diverse photosensitive layers, or, when the batch production is large and the production capacity of a single immersion developing or a single spray developing is insufficient, the composite developing process can be selected to jointly complete the developing operation of the cell 30. Of course, along the transmission direction, the single-sided composite developing operation of the cell 30 can be sequentially performed, that is, immersion developing and open spray developing are carried out, and the attached drawings are omitted.

[0088] Certainly, along the transmission direction, the single-sided immersion developing of the cell 30 can also be sequentially performed in the first tube developing tank and the single-sided spray developing in the second developing tank (the attached drawings are omitted). For these two composite developing units 10, they are more suitable for the operation of cells 30 with diverse photosensitive layers, or, when the batch production is large and the production capacity of a single immersion developing or a single spray developing is insufficient, the composite developing process can be selected to jointly complete the developing operation of the cell 30 and obtain a cell 30 as Figure 6 or Figure 7 shown.

[0089] Whether it is an immersion developing operation, an open developing operation or a composite developing operation, the developing solution in all developing tanks is an alkaline chemical solution. The alkaline chemical solution is sodium hydroxide or potassium hydroxide. Among them, when the alkaline chemical solution is sodium hydroxide or potassium hydroxide, its volume concentration range is 0.01 - 5%. Regardless of the alkaline chemical solution, the temperature range in all developing tanks is 10 - 50 °C.

[0090] A cleaning tank 21 is provided in the cleaning unit 20, and a drying oven 22 is also provided after the cleaning tank 21, and there is at least one cleaning tank 21 and one drying oven 22 in the cleaning unit 20. The cell 30 in the cleaning tank 21 and the drying oven 22 is still clamped by the transmission line 40 to drive the cell 30 to continue moving forward, and nozzles are provided on both the upper and lower sides of the cell 30. The solution sprayed in the cleaning tank 21 is pure water, mainly used to clean the upper and lower surfaces of the developed cell 30 to remove the residual chemical solution and the unetched film layer on the surface of the cell 30.

[0091] During the cleaning process, it is necessary to clean both sides of the battery cell 30, which can not only expose the metallization area 32 to be processed, but also remove the residual developer solution on the surface of the battery cell 30. By controlling the spraying pressure of the spray heads 50 on both sides, the spraying area and spraying method can be controlled to completely clean the upper and lower surfaces of the battery cell 30.

[0092] After the cleaning is completed, the battery cell 30 is then driven to move forward along the transmission line 40 into the drying oven 22, and the cold air for jet drying is controlled by the upper and lower spray heads 50 to blow dry the water droplets on the surface of the battery cell 30, so as to obtain a clean and tidy battery cell 30 with fine grid lines of a certain shape.

[0093] A battery cell grid line development preparation process designed by the present application is mainly used for performing a composite development operation on a horizontally placed battery cell. Different control methods of development cleaning can be selected based on the requirements of different battery cells, which can effectively solve the technical problem of easy occurrence of patterning obstacles in the development process. Not only can fine grid lines with clear patterns and precise lines be obtained, but also the bottom of the fine grid lines is developed cleanly and the overall consistency is good; this preparation process can not only ensure the development quality and improve the development effect, but also ensure the photoelectric conversion efficiency and output power of the battery cell. The present application also proposes a production device adapted to this development preparation process.

[0094] The above has described the embodiments of the present application in detail. The above content is only the preferred embodiments of the present application and cannot be considered as limiting the scope of implementation of the present application. All equivalent changes and improvements made within the scope of the present application should still fall within the scope covered by the patent of the present application.

Claims

1. A preparation process for battery cell grid line development, characterized in that the steps Comprising: Performing an immersion and / or open development operation on the exposed solar cell to wash away the unexposed part, so as to obtain the opening area where the fine grid lines are located in the solar cell; Washing the developed solar cell to expose the metallization area to be processed.

2. The preparation process of the grid line development of a battery chip according to claim 1, characterized in that The immersion and / or open development operation is to develop the horizontally placed solar cell; Preferably, when performing the immersion development operation on the solar cell, control the single-sided or double-sided immersion of the solar cell in the developer to perform single-sided or double-sided development on the solar cell; Preferably, when performing an open development operation on the battery cell, the developer is sprayed on both sides of the battery cell, wherein the spray pressure of the developer is controlled within a range of 0.5 - 3.5 kg / cm 2 .

3. A preparation process for developing battery cell grid lines according to claim 1 or 2, characterized in that The developer in all the development tanks is an alkaline liquid medicine; Preferably, the alkaline liquid medicine is sodium hydroxide or potassium hydroxide.

4. The manufacturing process for developing the grid lines of a battery cell according to claim 3, characterized in that, When the alkaline liquid medicine is sodium hydroxide or potassium hydroxide, its volume concentration range is 0.01-5%.

5. A preparation process for developing the grid lines of a battery cell according to claim 4, characterized in that, The temperature range of all the developers is 10-50°C.

6. The preparation process of the grid line development of the battery chip according to claim 1, characterized in that, The washing of the developed solar cell includes washing the surface of the solar cell with pure water and then drying the washed solar cell; Preferably, before performing the immersion and / or open development operation on the exposed solar cell, the step of obtaining the exposed solar cell is further included.

7. A battery cell grid line development production device, characterized in that, Applicable to the preparation process as described in any one of claims 1-6, having a development unit and a washing unit, wherein the development unit is equipped with a development tank, and the development unit is arranged on the side close to the solar cell feeding port; the washing unit is arranged on the side close to the solar cell discharging port.

8. A battery cell grid line development production device according to claim 7, characterized in that, The development unit includes an immersion development tank and / or an open development tank, and a transmission line for driving the horizontal movement of the solar cell is provided in all the development tanks; Preferably, in the development unit, at least one immersion development tank is provided; Preferably, at least one open development tank is further included in the immersion development tank; Preferably, in the immersion development tank, both sides of the solar cell are completely immersed in the developer in the tank or its single side is immersed in the developer in the tank.

9. A battery cell grid line development production device according to claim 7 or 8, characterized in that, A transmission line for transmitting the solar cell is further provided in the development unit, which is horizontally configured in the development unit and the washing unit; Preferably, the transmission line includes a plurality of rollers arranged in pairs, and the rollers clamp the solar cell and drive the solar cell to move forward.

10. A battery cell grid line development production device according to claim 7, characterized in that, A plurality of spray nozzles for spraying the liquid medicine are further provided in the development unit, and the spray nozzles are respectively arranged on the upper and lower sides of the solar cell and spray towards the surface of the solar cell; The spray nozzle is configured as a fixed structure or a swing structure; Preferably, the washing unit further includes a washing tank; a drying oven is further provided after the washing tank; Preferably, an ultrasonic device is further provided in the immersion development tank.

Images