Topcon battery and back surface micro texturing process and equipment thereof

Abstract

The invention discloses a Topcon battery and a back micro-texturing process and equipment thereof, and relates to the technical field of solar battery piece manufacturing, and the Topcon battery back micro-texturing process comprises the following steps: micro-texturing: carrying out micro-texturing treatment on a silicon wafer washed for the second time through texturing equipment, and carrying out texturing treatment through the process formula. The change of material physicochemical properties caused by the doping concentration difference caused by single-side boron diffusion on the edge and the middle of the silicon wafer is eliminated, the back surface morphology with the edge and the middle tower footing being consistent in size and uniform in distribution is obtained, hydrogen escape in the technological process is facilitated, the film explosion risk is reduced, and the production efficiency is improved through the alternate texturing process. By reasonably limiting the volume of the reaction solution and quantitatively injecting the reaction solution with the same concentration, the texturing effect can be ensured, the waste of the reaction solution can be reduced, meanwhile, the waste gas can be collected in the reaction process, and the external environment interference can be reduced and the texturing quality can be improved in the liquid operation process.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cell manufacturing, and in particular to a Topcon cell and a back micro-texturing process and equipment thereof. Background Art

[0002] The Topcon cell is a tunneling oxide passivation contact solar cell technology based on the principle of selective carriers. Its cell structure is an N-type silicon substrate cell. An ultra-thin layer of silicon oxide is prepared on the back of the cell, and then a thin layer of doped silicon is deposited. The two together form a passivation contact structure, effectively reducing surface recombination and metal contact recombination.

[0003] In the prior art document, a new method for optimizing the back surface morphology of a TOPCON battery with publication number CN117080311A includes the following steps: S1, preparing battery materials. S2, performing a damage layer etching process to remove the mechanical damage layer. S3, performing double-sided texturing. S4, preparing the back microstructure. S5, obtaining an alkali-polished sample on the back. S6, performing rounding treatment. S7, forming a heavily doped polysilicon passivation contact structure. S8, removing the oxide layer. S9, depositing an aluminum oxide anti-reflection film and a silicon nitride anti-reflection film. S10, metal contact, and performing data testing. This application uses ozone and acid mixed solution technology as a rounding process to round off the pyramid valleys and the concave areas between the towers at the polishing interface of the battery silicon wafer, which not only improves the back micromorphology, effectively improves the passivation effect and the electrical performance of the solar cell, but also significantly reduces the contact resistance, obtains a higher fill factor at the battery electrical performance end, and thus improves the conversion efficiency.

[0004] In the existing technology, the difference in doping concentration between the edge and the middle of the silicon wafer due to single-sided boron diffusion leads to a large difference in the size of the tower base blocks at the edge of the substrate and the center after alkaline polishing. During the texturing process, the concentration of the alkaline solution will change, which is difficult to adjust, affecting the subsequent texturing quality. Moreover, a large amount of waste will be caused by complete replacement due to the large volume capacity of the reaction tank. In addition, waste gas is easily generated during the texturing reaction process. The chain-type texturing structure makes it difficult to collect waste gas and is not conducive to the escape of hydrogen in the process, resulting in easy film explosion of the battery cell. Summary of the Invention

[0005] The purpose of the present invention is to provide a micro-texturing process for the back of a Topcon battery to solve the following technical problems: due to the large volume capacity of the reaction tank, a large amount of waste is caused, and waste gas is easily generated during the texturing reaction process. The chain-type texturing structure makes it difficult to collect the waste gas and is not conducive to the escape of hydrogen during the process, which makes the battery cell prone to film explosion.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A micro-texturing process for the back side of a Topcon battery comprises the following steps:

[0008] S1: Pre-cleaning: Pre-clean the silicon wafer to remove organic dirt and metal impurities on the surface.

[0009] S2: First water washing, washing the pre-cleaned silicon wafer for the first time.

[0010] S3: Alkali polishing, alkali polishing the silicon wafer after the first water washing.

[0011] S4: Second water washing, the alkali polished silicon wafer is washed for the second time.

[0012] S5: Micro-texturing, the silicon wafer after the second water washing is subjected to micro-texturing treatment through the texturing equipment.

[0013] S6: The third water washing is to wash the silicon wafer after micro-texturing for the third time.

[0014] S7: Ozone oxidation, ozone oxidation treatment is performed on the silicon wafer after the third water washing.

[0015] S8: The fourth water washing is to wash the silicon wafer after ozone oxidation for the fourth time.

[0016] S9: Pulling, using cold water pulling.

[0017] S10: Drying: Drying the pulled silicon wafer.

[0018] Preferably, the micro-texturing solution in step S5 has a ratio of 1.5%-1.6% NaOH and 0.09%-0.10% Add1, and the Add1 is Shichuang TS55 type texturing additive.

[0019] Preferably, the pre-cleaning time in step S1 is 110-120s, and the temperature is 60-70°C. The first water washing time in step S2 is 55-65s. The alkali polishing temperature in step S3 is 60-70°C, and the time is 180-200s. The second water washing time in step S4 is 55-65s. The micro-texturing temperature in step S5 is 80±2°C, and the time is 200-300s. The third water washing time in step S6 is 55-65s. The ozone oxidation temperature in step S7 is 20-30°C, and the time is 60-120s. The fourth water washing time in step S8 is 55-65s. The pulling time in step S9 is 15-25s. The drying temperature in step S10 is 90°C±10°C, and the time is 10-14min.

[0020] Another object of the present invention is to provide a Topcon battery, including a Topcon battery back side, wherein the Topcon battery back side is manufactured using a Topcon battery back side micro-texturing process.

[0021] Another object of the present invention is to provide a Topcon battery back micro-texturing device for realizing the Topcon battery back micro-texturing process, comprising a base, a first support plate installed on the top side of the base, a mounting hole opened in the middle of the first support plate, a rotating column rotatably installed in the mounting hole, and the bottom end of the rotating column rotatably installed on the bottom of the base.

[0022] Two supporting guard plates are symmetrically installed on the top side of the first supporting plate. A sliding groove is provided on the top of the rotating column in the vertical direction. A slider is slidingly provided inside the sliding groove. A connecting rod is connected to the slider, and a storage structure is fixed on the connecting rod.

[0023] A water storage tank is installed on the outside of the base, and a protective cover is installed on the water storage tank. A liquid inlet pipe is connected to the protective cover, and a limiting ring is fixed on the inner wall of the bottom end of the liquid inlet pipe. A telescopic column is movably inserted into the bottom port of the liquid inlet pipe, and an L-shaped guide hole is opened on the upper half of the telescopic column. A spring is fixed between the top of the telescopic column and the limiting ring.

[0024] A drainage hole is provided on the bottom side wall of the diversion hole. The drainage hole and the bottom port of the diversion hole are arranged in the same vertical direction. A water pressure gauge is installed on the top of the liquid inlet pipe. As the solution in the carrying bucket is poured, when the poured liquid exceeds the water level line of the connecting hole, the liquid enters the cavity on one side of the water storage tank through the connecting hole. As the liquid level in the cavity rises, the buoyancy guard plate, which is affected by the buoyancy force, gradually rises. After the buoyancy guard plate rises, the connecting hole is blocked, and the carrying bucket for texturing can be fully filled with liquid. Since the reaction space in the carrying bucket is limited, quantitative liquid injection is performed according to the required amount, which can achieve texturing treatment of the battery cell. Quantitative liquid injection can reduce the waste of reaction solution, and at the same time can ensure quantitative texturing, avoiding excessive corrosion of the battery cell caused by excessive solution.

[0025] As a further solution of the present invention: a lifting cylinder is installed on the outside of the water storage tank, and a lifting plate is installed on the active end of the lifting cylinder, and the lifting plate is fixed on one side of the protective cover, and an air pump is installed on the protective cover, the air inlet end of the air pump is connected to the protective cover through an air guide pipe, the exhaust end of the air pump is connected to the exhaust pipe, the exhaust pipe is connected to a connecting head, a one-way valve is installed on the exhaust pipe, a gas tank is rotatably assembled on the connecting head, and a locking valve is installed at the port of the gas tank, and the reaction area is covered by the protective cover. During the reaction process, the exhaust gas is pumped out by the air pump and collected by the gas tank connected to the connecting head. The exhaust gas generated by the reaction is concentrated and transported to the gas tank, and then the exhaust gas in the gas tank is transferred and processed, which can avoid direct discharge of the exhaust gas. At the same time, through the coverage of the protective cover, the reaction environment of the battery cell can be guaranteed to be relatively safe, and at the same time, it can avoid interference from the external environment, thereby achieving better texturing effect.

[0026] As a further solution of the present invention: a limiting plate is fixed on the middle inner wall of the base, a driving motor is installed on the bottom side of the limiting plate, a gear is installed on the output shaft of the driving motor, a gear ring is fixed on the outer side of the bottom end of the rotating column, and the gear ring and the gear are engaged with each other.

[0027] As a further solution of the present invention: the storage structure includes a carrying bucket, the carrying bucket is fixed at one end of the connecting rod, a slide rail is installed on the bottom inner wall of the carrying bucket, a second support plate is slidably installed on the slide rail, a second movable plate is fixed to one side of the bottom of the second support plate, a second magnetic block is installed on one side of the second movable plate, a mounting plate is fixed to the top side of the carrying bucket, a first magnetic block is fixed to one side of the mounting plate, and the first magnetic block and the second magnetic block are opposite magnets.

[0028] As a further embodiment of the present invention, a first movable plate is fixed to the bottom side of the lifting plate, a positioning rod is fixed to the top side of the first movable plate, a buoyancy guard plate is slidably mounted on the positioning rod, and a blocking plate is fixed to one side of the first movable plate. A partition plate is vertically fixed to the middle of the water storage tank, a diversion hole is formed in the interior of the partition plate, and the blocking plate is slidably mounted at the end of the diversion hole.

[0029] As a further embodiment of the present invention, the water storage tank is provided with a drainage hole and a connecting hole on its inner side, a buoyancy guard plate is provided on the outer side of the connecting hole, a sealing gasket is provided on the outer side of the carrying bucket, the drainage hole is lower than the connecting hole, the water storage tank is divided into two parts by a partition plate, wherein the bottom height of the cavity connected to the connecting hole is higher than the bottom height of the cavity connected to the drainage hole, and the cavity connected to the drainage hole is connected to a drainage pipe. During the micro-texturing process, after the texturing is completed, the lifting plate can be pushed upward with the cooperation of the lifting cylinder. After the first movable plate rises, the connecting hole is opened, and most of the liquid in the carrying bucket can be discharged into the cavity on one side of the water storage tank through the connecting hole. At this time, the diversion hole on the partition plate is also opened, and the reaction liquid entering the cavity on one side of the water storage tank is discharged into the cavity on the other side of the water storage tank through the diversion hole. At the same time, the connecting rod is lifted by the support guard plate, so that the bottom end of the placement hole is connected in parallel with the drainage hole, which can ensure that the reaction solution in the carrying bucket is completely emptied, avoid solution residue, and reduce the workload of subsequent operations.

[0030] Beneficial effects of the present invention:

[0031] The texturing treatment is performed through the above-mentioned process formula to eliminate the changes in the physical and chemical properties of the material caused by the difference in doping concentration between the edge and the middle of the silicon wafer due to single-sided boron diffusion, and obtain a back-side morphology with the edge and the middle tower base of the same size and uniform and staggered distribution. This is conducive to the escape of hydrogen during the process, reduces the risk of film explosion, and helps to improve the optical and electrical properties of the battery.

[0032] Through the rotating texturing process, the volume of the reaction liquid can be reasonably limited, and the reaction solution of the same concentration can be quantitatively injected to ensure the texturing effect and reduce the waste of the reaction liquid. At the same time, during the reaction process, the waste gas can be collected, and during the liquid operation process, the external environmental interference can be reduced to improve the texturing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below with reference to the accompanying drawings;

[0034] Figure 1 This is a schematic diagram of the three-dimensional structure of the texturing equipment from the first perspective;

[0035] Figure 2 This is a schematic diagram of the three-dimensional structure of the texturing equipment from the second perspective;

[0036] Figure 3 This is a diagram showing the internal structure of the water storage tank of the cashmere making equipment;

[0037] Figure 4 This is a diagram showing the location of the connecting holes in the water tank;

[0038] Figure 5This is a schematic diagram of the rotary column drive structure in the texturing equipment;

[0039] Figure 6 yes Figure 2 A top view of the structure;

[0040] Figure 7 yes Figure 6 Schematic diagram of the CC section structure along the middle edge;

[0041] Figure 8 This is a schematic diagram of the exhaust structure on the top of the protective cover;

[0042] Figure 9 It is a schematic diagram of the storage structure;

[0043] Figure 10 yes Figure 7 Schematic diagram of the structure of the middle A area;

[0044] Figure 11 yes Figure 7 Schematic diagram of the structure of the middle B area;

[0045] Figure 12 It is a schematic diagram of the velvet making process.

[0046] Figure: 1, base, 2, water storage tank, 3, first support plate, 4, support guard plate, 5, storage structure, 6, connecting rod, 7, slider, 8, rotating column, 9, slide, 10, protective cover, 11, liquid inlet pipe, 12, lifting plate, 13, lifting cylinder, 14, drainage hole, 15, water pressure gauge, 16, partition plate, 17, blocking plate, 18, first movable plate, 19, buoyancy guard plate, 20, positioning rod, 21, limit plate, 22, gear ring, 23, gear, 24, drive Drive motor, 101, air pump, 102, exhaust pipe, 103, connector, 104, one-way valve, 105, air tank, 106, locking valve, 51, carrying bucket, 52, placement hole, 53, second movable plate, 54, second support plate, 55, slide rail, 56, support frame, 57, first magnetic block, 58, second magnetic block, 59, mounting plate, 1101, drainage hole, 1102, spring, 1103, limit ring, 1104, guide hole, 1105, telescopic column. DETAILED DESCRIPTION

[0047] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0048] See also Figure 12As shown, the present invention is a micro-texturing process for the back side of a Topcon battery, comprising the following steps:

[0049] S1: Pre-cleaning: Pre-clean the silicon wafer to remove organic dirt and metal impurities on the surface. The cleaning time is 115 seconds and the temperature is 65°C. In another embodiment, the pre-cleaning time is 110 seconds and the temperature is 70°C. In another embodiment, the pre-cleaning time is 120 seconds and the temperature is 60°C.

[0050] S2: First water wash: The pre-cleaned silicon wafer is subjected to a first water wash for 60 seconds. In another embodiment, the first water wash time is 55 seconds. In yet another embodiment, the first water wash time is 65 seconds.

[0051] S3: Alkali polishing: Alkali polishing is performed on the silicon wafer after the first water wash at a temperature of 64°C for 190 seconds. In another embodiment, the alkaline polishing temperature is 60°C for 200 seconds. In another embodiment, the alkaline polishing temperature is 70°C for 180 seconds.

[0052] S4: Second water washing: The alkali polished silicon wafer is subjected to a second water washing for 60 seconds. In another embodiment, the second water washing time is 55 seconds. In another embodiment, the second water washing time is 65 seconds.

[0053] S5: Micro-texturing: The silicon wafer after the second water wash is subjected to micro-texturing using a texturing device. The micro-texturing solution is a mixture of 1.5%-1.6% NaOH and 0.09%-0.10% Add1. The temperature is 80°C for 250 seconds. Add1 is Shichuang TS55 texturing additive. In another embodiment, the micro-texturing temperature is 82°C for 200 seconds. In yet another embodiment, the micro-texturing temperature is 78°C for 300 seconds.

[0054] S6: Third water washing: The micro-textured silicon wafer is washed for a third time for 60 seconds. In another embodiment, the third water washing time is 55 seconds. In another embodiment, the third water washing time is 65 seconds.

[0055] S7: Ozone oxidation: The silicon wafer after the third water wash is subjected to ozone oxidation treatment at a temperature of 25°C for 90 seconds. In another embodiment, the ozone oxidation temperature is 20°C for 120 seconds. In yet another embodiment, the ozone oxidation temperature is 30°C for 60 seconds.

[0056] S8: Fourth water wash: The ozone-oxidized silicon wafer is washed with water for a fourth time for 60 seconds. In another embodiment, the fourth water wash time is 55 seconds. In another embodiment, the fourth water wash time is 65 seconds.

[0057] S9: Pulling, using cold water pulling, at room temperature for 20 seconds. In another embodiment, the pulling time is 15 seconds. In another embodiment, the pulling time is 25 seconds.

[0058] S10: Drying: Dry the pulled silicon wafer at 90°C for 12 minutes. In another embodiment, the drying temperature is 80°C for 14 minutes. In another embodiment, the drying temperature is 100°C for 10 minutes.

[0059] Before alkaline polishing, the above-mentioned process formula is used for texturing treatment to eliminate the changes in the physical and chemical properties of the material caused by the difference in doping concentration between the edge and the middle of the silicon wafer due to single-sided boron diffusion, so as to obtain a back-side morphology with the edge and the middle tower base of the same size and uniform distribution. This is conducive to the escape of hydrogen during the process and reduces the risk of film explosion.

[0060] In the micro-texturing process on the back of Topcon batteries, the main chemical reaction equations involved are:

[0061] Si+2NaOH+H2O→Na2SiO3+2H2↑.

[0062] This corrosion effect forms a micro-texture structure on the surface of the silicon wafer, which helps to improve the optical and electrical properties of the battery.

[0063] In another embodiment, a Topcon battery is provided, including a Topcon battery back side, wherein the Topcon battery back side is manufactured by a Topcon battery back side micro-texturing process.

[0064] In another embodiment, a Topcon battery back micro-texturing device is provided, such as Figures 1-4 、 Figure 10 As shown, it is used to realize the micro-texturing process on the back of the Topcon battery, including a base 1, a first support plate 3 is installed on the top side of the base 1, a mounting hole is opened in the middle of the first support plate 3, a rotating column 8 is rotatably installed in the mounting hole, and the bottom end of the rotating column 8 is rotatably installed on the bottom of the base 1.

[0065] Two support guard plates 4 are symmetrically installed on the top side of the first support plate 3. A slide groove 9 is provided on the top of the rotating column 8 in the vertical direction. A slider 7 is slidingly provided inside the slide groove 9. A connecting rod 6 is connected to the slider 7, and a storage structure 5 is fixed on the connecting rod 6.

[0066] A water tank 2 is installed on the outside of the base 1, and a protective cover 10 is installed on the water tank 2. A liquid inlet pipe 11 is connected to the protective cover 10, and a limiting ring 1103 is fixed on the inner wall of the bottom end of the liquid inlet pipe 11. A telescopic column 1105 is movably inserted into the bottom port of the liquid inlet pipe 11, and an L-shaped guide hole 1104 is opened on the upper half of the telescopic column 1105. A spring 1102 is fixed between the top of the telescopic column 1105 and the limiting ring 1103.

[0067] A drainage hole 1101 is provided on the bottom side wall of the guide hole 1104 . The drainage hole 1101 and the bottom port of the guide hole 1104 are arranged along the same vertical direction. A water pressure gauge 15 is installed at the top of the liquid inlet pipe 11 .

[0068] See also Figure 1 、 Figure 6-Figure 8 As shown, a lifting cylinder 13 is installed on the outside of the water tank 2, and the lifting cylinder 13 is controlled by a CNC PLC controller. A lifting plate 12 is installed on the active end of the lifting cylinder 13, and the lifting plate 12 is fixed on one side of the protective cover 10. An air pump 101 is installed on the protective cover 10, and the air pump 101 is controlled by a CNC PLC controller. The air inlet end of the air pump 101 is connected to the protective cover 10 through an air guide pipe, and the exhaust end of the air pump 101 is connected to an exhaust pipe 102, and a connector 103 is connected to the exhaust pipe 102. A one-way valve 104 is installed on the exhaust pipe 102, and an air tank 105 is rotatably assembled on the connector 103, and a locking valve 106 is installed at the port of the air tank 105.

[0069] When the battery cells are transported to the coverage area of ​​the water storage tank 2 , the storage structure 5 carrying the battery cells is transported so that the placement holes 52 are aligned with the communication holes on the inner wall of the water storage tank 2 .

[0070] At this time, the lifting cylinder 13 is operated to drive the lifting plate 12 downward, so that the protective cover 10 is vertically pressed on the storage structure 5 carrying the battery cells.

[0071] At this time, the bottom end of the telescopic column 1105 contacts the bottom of the carrying bucket 51. After the protective cover 10 subsequently descends, the liquid inlet pipe 11 descends relative to the telescopic column 1105, and the spring 1102 is compressed, so that the bottom port of the guide hole 1104 is aligned with the spring 1102, so that the reaction solution transported through the liquid inlet pipe 11 is discharged through the drainage hole 1101, thereby realizing the perfusion of the reaction solution into the carrying bucket 51.

[0072] During the synchronous descent of the lifting plate 12 and the protective cover 10, the positioning rod 20 is driven downward, the positioning rod 20 moves downward, the blocking plate 17 blocks the guide hole on the partition plate 16, and the buoyancy guard plate 19 descends to the outer port of the connecting hole.

[0073] As the solution in the carrying bucket 51 is poured, when the poured liquid exceeds the water level line of the connecting hole, the liquid enters the cavity on one side of the water storage tank 2 through the connecting hole. As the liquid level in the cavity rises, the buoyancy guard plate 19, which is affected by the buoyancy, gradually rises. After the buoyancy guard plate 19 rises, the connecting hole is sealed, and the carrying bucket 51 for texturing can be fully filled with liquid. Since the reaction space in the carrying bucket 51 is limited, quantitative liquid injection is performed according to the required amount, which can achieve texturing treatment of the battery cell.

[0074] By quantitatively injecting liquid, the waste of reaction solution can be reduced, and quantitative texturing can be ensured, avoiding excessive corrosion of the battery cell caused by excessive solution.

[0075] During the texturing process, a mixed gas mainly composed of hydrogen will be generated. In order to reduce the direct emission of waste gas, the reaction area is covered by the protective cover 10. During the reaction, the gas can be pressurized and transported to the connector 103 through the exhaust pipe 102 through the extraction of the air pump 101, and collected by the gas tank 105 connected to the connector 103. The waste gas generated by the reaction is concentrated and transported to the gas tank 105, and then the waste gas in the gas tank 105 is transferred and processed, which can avoid the direct emission of waste gas. At the same time, through the coverage of the protective cover 10, the reaction environment of the battery cell can be guaranteed to be relatively safe, and the interference of the external environment can be avoided, so as to achieve a better texturing effect.

[0076] See also Figure 5 As shown, a limit plate 21 is fixed on the middle inner wall of the base 1, and a drive motor 24 is installed on the bottom side of the limit plate 21. The drive motor 24 controls the operation under the CNC PLC controller. A gear 23 is installed on the output shaft of the drive motor 24, and a ring gear 22 is fixed on the outer side of the bottom end of the rotating column 8. The ring gear 22 and the gear 23 are engaged with each other.

[0077] See also Figure 9 、 Figure 11 As shown, the storage structure 5 includes a carrying bucket 51, which is fixed to one end of the connecting rod 6, and a slide rail 55 is installed on the bottom inner wall of the carrying bucket 51. A second support plate 54 is slidably installed on the slide rail 55, and a second movable plate 53 is fixed to one side of the bottom of the second support plate 54. A second magnetic block 58 is installed on one side of the second movable plate 53. A mounting plate 59 is fixed to the top side of the carrying bucket 51, and a first magnetic block 57 is fixed to one side of the mounting plate 59. The first magnetic block 57 and the second magnetic block 58 are opposite magnets.

[0078] When micro-texturing the back of the battery and loading the battery cells, the storage structure 5 is rotated to the loading position and the second movable plate 53 is pulled. Under the action of external tension, the first magnetic block 57 and the second magnetic block 58 attracted together are separated, and the second support plate 54 can be pulled along the slide rail 55 to draw a placement hole 52. The battery cells are placed on the second support plate 54 and supported by the support frame 56 on the top of the second support plate 54. This can reduce the interference of the support on the texturing of the battery cells and improve the texturing effect.

[0079] During loading, the second support plate 54 with the battery cells placed thereon is pushed into the carrying bucket 51. When the second magnetic block 58 and the first magnetic block 57 are fixed to each other by adsorption, the second support plate 54 can be fixed to ensure the stability of the battery cells.

[0080] A first movable plate 18 is fixed to the bottom side of the lifting plate 12 , a positioning rod 20 is fixed to the top side of the first movable plate 18 , a buoyancy guard plate 19 is slidably provided on the positioning rod 20 , and a blocking plate 17 is fixed to one side of the first movable plate 18 .

[0081] A partition plate 16 is vertically fixed to the middle of the water storage tank 2, and a diversion hole is opened inside the partition plate 16. The blocking plate 17 is slidably arranged at the port of the diversion hole. A drainage hole 14 and a connecting hole are opened on the inner side of the water storage tank 2. A buoyancy guard plate 19 is arranged on the outside of the connecting hole. A sealing gasket is provided on the outside of the carrying bucket 51 to ensure that the inner wall of the water storage tank 2 can be leached when the carrying bucket 51 rotates, and the overflow of the reaction solution can be avoided. The horizontal height of the drainage hole 14 is lower than the horizontal height of the connecting hole. The water storage tank 2 is divided into two parts by the partition plate 16, and the bottom height of the cavity connected to the connecting hole is higher than The bottom height of the cavity connected to the drainage hole 14, and the cavity connected to the drainage hole 14 is connected to a drainage pipe. After the texturing is completed, the lifting plate 12 can be pushed upward with the cooperation of the lifting cylinder 13. After the lifting plate 12 rises, it can drive the first movable plate 18 to rise under the drive of the positioning rod 20. After the first movable plate 18 rises, the connecting hole is opened, and most of the liquid in the carrying bucket 51 can be discharged to the cavity on one side of the water tank 2 through the connecting hole. At this time, the diversion hole on the partition plate 16 is also opened, and the reaction liquid entering the cavity on one side of the water tank 2 is discharged to the cavity on the other side of the water tank 2 through the diversion hole.

[0082] At this time, the driving motor 24 operates again, and with the cooperation of the gear 23 and the limiting plate 21 , drives the rotating column 8 to rotate.

[0083] When the rotating column 8 rotates, since the support guard plate 4 is symmetrically installed on the base 1, when the connecting rod 6 rotates, the slider 7 slides along the slide groove 9, and the connecting rod 6 is lifted by the action of the support guard plate 4, so that the bottom port of the placement hole 52 is connected in parallel with the drainage hole 14, which can ensure that the reaction solution in the carrying bucket 51 is completely emptied, avoid solution residue, and reduce the workload of subsequent operations.

[0084] In this embodiment, when performing micro-texturing, the texturing operation on the back of the battery cell is achieved through the contact between the battery cell and the solution.

[0085] When loading the battery cells, the storage structure 5 is rotated to the loading position, and the second movable plate 53 is pulled. Under the action of external tension, the first magnetic block 57 and the second magnetic block 58 attracted together are separated, and the second support plate 54 can be pulled along the slide rail 55 to draw a placement hole 52. The battery cells are placed on the second support plate 54, and the battery cells are supported by the support frame 56 on the top of the second support plate 54. This can reduce the interference of the support on the texturing of the battery cells and improve the texturing effect.

[0086] During loading, the second support plate 54 with the battery cells placed thereon is pushed into the carrying bucket 51. When the second magnetic block 58 and the first magnetic block 57 are attracted and fixed to each other, the second support plate 54 can be fixed to ensure the stability of the battery cells.

[0087] After the loading is completed, the gear 23 is driven to rotate by driving the driving motor 24, and the rotating column 8 can be driven to rotate 90 degrees in a single time with the cooperation of the gear ring 22 to transport the material.

[0088] When the battery cells are transported to the coverage area of ​​the water storage tank 2 , the storage structure 5 carrying the battery cells is transported so that the placement holes 52 are aligned with the communication holes on the inner wall of the water storage tank 2 .

[0089] At this time, the lifting cylinder 13 is operated to drive the lifting plate 12 downward, so that the protective cover 10 is vertically pressed on the storage structure 5 carrying the battery cells.

[0090] At this time, the bottom end of the telescopic column 1105 contacts the bottom of the carrying bucket 51. After the protective cover 10 subsequently descends, the liquid inlet pipe 11 descends relative to the telescopic column 1105, and the spring 1102 is compressed, so that the bottom port of the guide hole 1104 is aligned with the spring 1102, so that the reaction solution transported through the liquid inlet pipe 11 is discharged through the drainage hole 1101, thereby realizing the perfusion of the reaction solution into the carrying bucket 51.

[0091] During the synchronous descent of the lifting plate 12 and the protective cover 10, the positioning rod 20 is driven downward, the positioning rod 20 moves downward, the blocking plate 17 blocks the guide hole on the partition plate 16, and the buoyancy guard plate 19 descends to the outer port of the connecting hole.

[0092] As the solution in the carrying bucket 51 is poured, when the poured liquid exceeds the water level line of the connecting hole, the liquid enters the cavity on one side of the water storage tank 2 through the connecting hole. As the liquid level in the cavity rises, the buoyancy guard plate 19, which is affected by the buoyancy, gradually rises. After the buoyancy guard plate 19 rises, the connecting hole is sealed, and the carrying bucket 51 for texturing can be fully filled with liquid. Since the reaction space in the carrying bucket 51 is limited, quantitative liquid injection is performed according to the required amount, which can achieve texturing treatment of the battery cell.

[0093] By quantitatively injecting liquid, the waste of reaction solution can be reduced, and quantitative texturing can be ensured, avoiding excessive corrosion of the battery cell caused by excessive solution.

[0094] During the texturing process, a mixed gas mainly composed of hydrogen will be generated. In order to reduce the direct emission of waste gas, the reaction area is covered by the protective cover 10. During the reaction, the gas can be pressurized and transported to the connector 103 through the exhaust pipe 102 through the extraction of the air pump 101, and collected by the gas tank 105 connected to the connector 103. The waste gas generated by the reaction is concentrated and transported to the gas tank 105, and then the waste gas in the gas tank 105 is transferred and processed, which can avoid the direct emission of waste gas. At the same time, through the coverage of the protective cover 10, the reaction environment of the battery cell can be guaranteed to be relatively safe, and the interference of the external environment can be avoided, so as to achieve a better texturing effect.

[0095] After the texturing is completed, the lifting plate 12 can be pushed upward with the cooperation of the lifting cylinder 13. After the lifting plate 12 rises, it can drive the first movable plate 18 to rise under the drive of the positioning rod 20. After the first movable plate 18 rises, the connecting hole is opened, and most of the liquid in the carrying bucket 51 can be discharged into the cavity on one side of the water tank 2 through the connecting hole. At this time, the guide hole on the partition plate 16 is also opened, and the reaction liquid entering the cavity on one side of the water tank 2 is discharged into the cavity on the other side of the water tank 2 through the guide hole.

[0096] At this time, the driving motor 24 operates again, and with the cooperation of the gear 23 and the limiting plate 21 , drives the rotating column 8 to rotate.

[0097] When the rotating column 8 rotates, since the support guard plate 4 is symmetrically installed on the base 1, when the connecting rod 6 rotates, the slider 7 slides along the slide groove 9, and the connecting rod 6 is lifted by the action of the support guard plate 4, so that the bottom port of the placement hole 52 is connected in parallel with the drainage hole 14, which can ensure that the reaction solution in the carrying bucket 51 is completely emptied, avoid solution residue, and reduce the workload of subsequent operations.

[0098] Through the rotating texturing process, the volume of the reaction liquid can be reasonably limited to reduce the waste of the reaction liquid. At the same time, during the reaction process, the waste gas can be collected. During the liquid operation process, the external environmental interference can be reduced and the texturing quality can be improved.

[0099] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A micro-texturing process for the back of a Topcon battery, characterized in that: The following steps are involved: S1: Pre-cleaning: Pre-clean the silicon wafer to remove organic dirt and metal impurities on the surface; S2: First water washing, washing the pre-cleaned silicon wafer for the first time; S3: Alkali polishing, alkali polishing the silicon wafer after the first water washing; S4: Second water washing, washing the alkali polished silicon wafer for the second time; S5: Micro-texturing, micro-texturing the silicon wafer after the second water washing by using a texturing device; S6: washing the silicon wafer after micro-texturing for the third time; S7: ozone oxidation, performing ozone oxidation treatment on the silicon wafer after the third water washing; S8: washing the silicon wafer after ozone oxidation for the fourth time; S9: pulling, using cold water pulling; S10: Drying: Drying the pulled silicon wafer.

2. The micro-texturing process for the back side of a Topcon battery according to claim 1, characterized in that: In step S5, the micro-texturing solution has a ratio of 1.5%-1.6% NaOH and 0.09%-0.10% Add1.

3. The micro-texturing process for the back side of a Topcon battery according to claim 2, characterized in that: The pre-cleaning time in step S1 is 110-120s, and the temperature is 60-70℃; the first water washing time in step S2 is 55-65s; the alkali polishing temperature in step S3 is 60-70℃, and the time is 180-200s; the second water washing time in step S4 is 55-65s; the micro-texturing temperature in step S5 is 80±2℃, and the time is 200-300s; the third water washing time in step S6 is 55-65s; the ozone oxidation temperature in step S7 is 20-30℃, and the time is 60-120s; the fourth water washing time in step S8 is 55-65s; the pulling time in step S9 is 15-25s; the drying temperature in step S10 is 90℃±10℃, and the time is 10-14min.

4. A Topcon battery, characterized in that: It comprises a Topcon battery back surface, and the Topcon battery back surface is made by using a Topcon battery back surface micro-texturing process according to any one of claims 1-3.

5. A texturing device based on the Topcon battery back micro-texturing process according to claim 1, characterized in that: The invention comprises a base (1), a first support plate (3) is installed on the top side of the base (1), a mounting hole is opened in the middle of the first support plate (3), a rotating column (8) is rotatably installed in the mounting hole, and the bottom end of the rotating column (8) is rotatably installed on the bottom of the base (1); Two supporting guard plates (4) are symmetrically mounted on the top side of the first supporting plate (3); a sliding groove (9) is provided on the top of the rotating column (8) in a vertical direction; a slider (7) is slidably arranged inside the sliding groove (9); a connecting rod (6) is connected to the slider (7); and a storage structure (5) is fixed to the connecting rod (6); A water storage tank (2) is installed on the outer side of the base (1), a protective cover (10) is installed on the water storage tank (2), a liquid inlet pipe (11) is connected to the protective cover (10), and a limiting ring (1103) is fixed on the inner wall of the bottom end of the liquid inlet pipe (11), a telescopic column (1105) is movably inserted through the bottom end of the liquid inlet pipe (11), an L-shaped guide hole (1104) is opened on the upper half of the telescopic column (1105), and a spring (1102) is fixed between the top end of the telescopic column (1105) and the limiting ring (1103); A drainage hole (1101) is provided on the bottom side wall of the diversion hole (1104). The drainage hole (1101) and the bottom port of the diversion hole (1104) are arranged along the same vertical direction. A water pressure gauge (15) is installed at the top end of the liquid inlet pipe (11).

6. The texturing equipment according to claim 5, characterized in that: A lifting cylinder (13) is installed on the outer side of the water storage tank (2), and a lifting plate (12) is installed on the active end of the lifting cylinder (13). The lifting plate (12) is fixed on one side of the protective cover (10). An air pump (101) is installed on the protective cover (10). The air inlet end of the air pump (101) is connected to the protective cover (10) through an air guide pipe. The exhaust end of the air pump (101) is connected to an exhaust pipe (102). A connector (103) is connected to the exhaust pipe (102). A one-way valve (104) is installed on the exhaust pipe (102). An air tank (105) is rotatably assembled on the connector (103). A locking valve (106) is installed at the port of the air tank (105).

7. The texturing equipment according to claim 6, characterized in that: A limiting plate (21) is fixed on the inner wall of the middle portion of the base (1), a driving motor (24) is installed on the bottom side of the limiting plate (21), a gear (23) is installed on the output shaft of the driving motor (24), and a gear ring (22) is fixed on the outer side of the bottom end of the rotating column (8), and the gear ring (22) and the gear (23) are meshed with each other.

8. The texturing equipment according to claim 7, characterized in that: The storage structure (5) includes a carrying bucket (51), the carrying bucket (51) is fixed to one end of the connecting rod (6), a slide rail (55) is installed on the bottom inner wall of the carrying bucket (51), a second support plate (54) is slidably installed on the slide rail (55), a second movable plate (53) is fixed to the bottom side of the second support plate (54), a second magnetic block (58) is installed on one side of the second movable plate (53), a mounting plate (59) is fixed to the top side of the carrying bucket (51), a first magnetic block (57) is fixed to one side of the mounting plate (59), and the first magnetic block (57) and the second magnetic block (58) are magnets of opposite polarity.

9. The texturing equipment according to claim 8, characterized in that: A first movable plate (18) is fixed to the bottom side of the lifting plate (12), a positioning rod (20) is fixed to the top side of the first movable plate (18), a buoyancy guard plate (19) is slidably provided on the positioning rod (20), and a sealing plate (17) is fixed to one side of the first movable plate (18); a partition plate (16) is vertically fixed to the middle of the water storage tank (2), a guide hole is opened inside the partition plate (16), and the sealing plate (17) is slidably provided at the end of the guide hole.

10. The texturing equipment according to claim 9, characterized in that: A drainage hole (14) and a connecting hole are provided on the inner side of the water storage tank (2), and a buoyancy guard plate (19) is provided on the outer side of the connecting hole; a sealing gasket is provided on the outer side of the carrying bucket (51), and the horizontal height of the drainage hole (14) is lower than the horizontal height of the connecting hole. The water storage tank (2) is divided into two parts by a partition plate (16), wherein the bottom height of the cavity connected to the connecting hole is higher than the bottom height of the cavity connected to the drainage hole (14), and a drainage pipe is connected to the cavity connected to the drainage hole (14).

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