Novel TOPCon battery preparation process and device

Abstract

The invention discloses a novel TOPCon battery preparation process and device, and relates to the technical field of battery processing, and the novel TOPCon battery preparation process comprises the following steps: S1, preparing a sheet; s2, scribing: segmenting the whole cell by using laser; s3, side face polishing is conducted, specifically, chain type etching and alkali washing are conducted on the cutting face, and the cutting face is corroded at the temperature of 30-60 DEG C through 10-30% of TMAH and 5-20% of IPA aqueous solution; s4, edge passivation is conducted, specifically, an aluminum oxide passivation film of 20-50 nm is deposited in an atomic layer deposition mode, and annealing is conducted for 30-60 min at the temperature of 250-300 DEG C; and S5, IV testing: testing the appearance, IV and EL performance of the battery piece, and then grading. Preferably, the flaking process comprises the steps of texturing and boron diffusion. According to the invention, a battery panel is driven to move in a manner of carrying liquid through a roller, and silicon, silicon nitride and silicon oxide on a cut surface of the battery can be corroded and polished by using a TMAH + IPA solution and an HF solution.

Description

Technical Field

[0001] This invention relates to the field of battery processing technology, specifically to a novel TOPCon battery manufacturing process and apparatus. Background Technology

[0002] With the rapid development of photovoltaic technology, various high-efficiency batteries have been developed. TOPCon battery is a tunnel oxide passivated contact solar cell based on N-type silicon wafer. In the production process, it usually needs to be divided into two or more pieces by laser cutting.

[0003] Existing TOPCon batteries are typically laser-scribed and then passivated films are deposited on the cut surfaces to mitigate the efficiency loss caused by the scriber. However, after laser scribes the battery, the cut surfaces are not smooth, and the thermal damage caused by the laser at the front and rear guide slots is also severe, which can easily affect the battery quality and efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a novel TOPCon battery manufacturing process and apparatus to overcome the aforementioned shortcomings in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a novel TOPCon battery manufacturing process, comprising the following steps:

[0006] S1, Production;

[0007] S2, Segmentation: Using a laser to divide the entire cell into sections;

[0008] S3. Side polishing: Chain etching of alkaline washing of the cut surface, using 10-30% TMAH and 5-20% IPA aqueous solution, etching the cut surface at 30-60℃.

[0009] S4. Edge passivation: Deposit a 20-50 nm aluminum oxide passivation film using atomic layer deposition, and anneal at 250-300℃ for 30-60 min.

[0010] S5 and IV tests: The cells are graded after testing their appearance, IV and EL performance.

[0011] Preferably, the wafer fabrication process includes texturing and boron diffusion. The texturing uses an N-type monocrystalline silicon wafer as the substrate and uses acid and alkali chemicals to texturize both sides of the monocrystalline silicon wafer to form a pyramid structure on the surface of the monocrystalline silicon wafer. In the boron diffusion, the boron source is BCl3.

[0012] Preferably, the side polishing step also includes a deionized water rinsing process, in which the cut surface is rinsed with deionized water after etching the cut surface with TMAH and IPA aqueous solutions.

[0013] Preferably, the side polishing step also includes hydrofluoric acid treatment. After the cut surface is cleaned with deionized water, a roller drives the battery panel into the hydrofluoric acid bath to remove the silicon oxide from the cut surface of the battery.

[0014] A novel TOPCon battery polishing device includes a base and a partition and a guide block fixedly mounted thereon, and further includes:

[0015] The rotating frame is rotatably mounted at the top center of the base;

[0016] The partitions are located on both sides of the rotating frame;

[0017] Guide blocks are set on both sides of the base, and the two guide blocks are combined with the two partitions in a one-to-one correspondence to form a guide groove;

[0018] A roller is rotatably mounted in a base, and a solution tank is provided on the base, with the roller disposed in the solution tank;

[0019] The drive mechanism drives the rollers to rotate to convey and polish the solar panels. While the rollers are rotating, they also cause the rotating frame to swing back and forth so that the solar panels above the rotating frame can be polished on both sides.

[0020] Preferably, an arc-shaped rod is fixedly installed at the bottom end of the rotating frame, and a connecting rod is fixedly installed on the arc-shaped rod;

[0021] A connecting shaft is fixedly mounted on one of the rollers. A sliding frame is threaded onto the connecting shaft. A sliding groove adapted to the size of the connecting rod is opened on the sliding frame, and the connecting rod is inserted into the sliding groove.

[0022] Preferably, the rotating frame consists of an outer frame and an intermediate rod, with a rotating shaft fixedly installed on the outer frame and a round rod fixedly installed between the intermediate rod and the outer frame.

[0023] Preferably, a slanted wheel is fixedly installed on one side of the roller.

[0024] Preferably, a long shaft is rotatably mounted on the base, and the shaft is rotatably mounted on the base, with a belt connecting the long shaft and the shaft for transmission.

[0025] A sliding rod is horizontally slidably mounted on the base, the long shaft and the sliding rod are in contact with each other, a rotating bar is rotatably mounted on the base, and a friction rod is fixedly mounted on the rotating bar, and the friction rod and the sliding rod are in contact with each other.

[0026] Preferably, the guide block includes an arc-shaped block and a long plate, with a conveying channel formed between the long plate and the partition.

[0027] Preferably, the surface of the rotating frame is chamfered.

[0028] Preferably, a friction wheel and a rotating wheel are rotatably mounted on the arc-shaped rod, wherein the friction wheel extends from the bottom end of the arc-shaped rod, and a transmission belt is provided between the friction wheel and the rotating wheel;

[0029] A rotating rod is rotatably mounted on the arc-shaped rod, and a first bevel gear is fixedly mounted on both ends of the rotating rod. A round bar is rotatably mounted inside the middle rod, a second bevel gear is fixedly mounted on the round bar, and a fan blade is fixedly mounted on the round bar.

[0030] The round rod is hollow, and several through holes are provided on the outer frame.

[0031] In the above technical solution, the present invention provides a novel TOPCon battery manufacturing process and apparatus, which has the following beneficial effects: while driving the battery panel to move by means of a roller carrying liquid, TMAH+IPA solution and HF solution can also be used to etch and polish the silicon, silicon nitride and silicon oxide on the battery cutting surface. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0033] Figure 1 A flowchart provided for an embodiment of the present invention

[0034] Figure 2 This is a three-dimensional structural schematic diagram provided for an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the side portion structure provided in an embodiment of the present invention;

[0036] Figure 4 Provided for embodiments of the present invention Figure 1 Top view;

[0037] Figure 5 This is a partial structural schematic diagram of the base provided in an embodiment of the present invention;

[0038] Figure 6 This is a partial structural diagram of the roller provided in an embodiment of the present invention;

[0039] Figure 7 This is a partial structural diagram of the slide bar provided in an embodiment of the present invention;

[0040] Figure 8 This is a partial structural diagram of the frame-turning mechanism provided in an embodiment of the present invention;

[0041] Figure 9 This is a partial structural schematic diagram of the arc-shaped rod provided in an embodiment of the present invention;

[0042] Figure 10 This is a partial structural diagram of the round rod provided in an embodiment of the present invention;

[0043] Figure 11 This is a partial structural diagram of the frame-turning mechanism provided in an embodiment of the present invention;

[0044] Figure 12 This is a partial structural diagram of the inclined wheel provided in an embodiment of the present invention.

[0045] Explanation of reference numerals in the attached figures:

[0046] 1. Base; 2. Inner block; 2.1. Solution tank; 3. Partition; 3.1. Conveying channel; 4. Guide block; 4.1. Long plate; 5. Battery panel; 61. Roller; 61.1. Inclined wheel; 62. Connecting shaft; 63. Sliding frame; 63.1. Sliding groove; 64. Connecting rod; 65. Arc rod; 66. Rotating frame; 66.1. Intermediate rod; 66.2. Chamfer; 67. Round rod; 71. Friction wheel; 72. Transmission belt; 73. Rotating wheel; 74. Rotating rod; 75. First bevel gear; 76. Round bar; 77. Second bevel gear; 78. Fan blade; 81. Rotating shaft; 82. Belt; 83. Long shaft; 84. Sliding rod; 85. Rotating bar. Detailed Implementation

[0047] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0048] Please see Figure 1-12 A novel TOPCon battery fabrication process includes the following steps:

[0049] S1, Production;

[0050] S2, Segmentation: Using a laser to divide the entire cell into sections;

[0051] S3. Side polishing: Chain etching of alkaline washing of the cut surface, using 10-30% TMAH and 5-20% IPA aqueous solution, etching the cut surface at 30-60℃.

[0052] S4. Edge passivation: Deposit a 20-50 nm aluminum oxide passivation film using atomic layer deposition, and anneal at 250-300℃ for 30-60 min.

[0053] S5 and IV tests: The cells are graded after testing their appearance, IV and EL performance.

[0054] In another embodiment of the present invention: the wafer fabrication process includes texturing and boron diffusion, wherein the texturing uses an N-type monocrystalline silicon wafer as the substrate, and acid and alkali chemicals are used to texture both sides of the monocrystalline silicon wafer to form a pyramid structure on the surface of the monocrystalline silicon wafer, and in the boron diffusion, the boron source is BCl3;

[0055] The film-making process also includes oxidation, BSG removal and alkali polishing, PE-poly process, annealing, RCA process, ALD process, coating, printing, and laser-assisted sintering.

[0056] In boron diffusion, the boron source is BCl3, and the diffusion sheet resistance is 100-150 Ω / □;

[0057] Next, an oxidation process is used to form BSG on the silicon wafer surface, with a thickness of 80-120nm and a sheet resistance of 250-350Ω / □.

[0058] The BSG removal and alkaline polishing process uses a chain machine. Under the protection of a water film, the front surface of the silicon wafer is cleaned by using a 28%-35% HF solution and rollers 61 to remove the borosilicate glass (BSG) from the back and four sides of the silicon wafer. After BSG removal, a tank machine is used to perform alkaline polishing on the back surface of the silicon wafer. The reaction solution is an alkali (KOH or NaOH or organic alkali) and a polishing agent, which react at 60-70℃ for 200 seconds to obtain a back surface with a reflectivity greater than 40% and a base thickness greater than 6µm. The front BSG is retained.

[0059] Next, a PE-poly (plasma-enhanced polycrystalline silicon deposition) process is performed. On the back side, a tunnel oxide layer and doped amorphous silicon are deposited using PECVD (chemical vapor deposition). The thickness of the ultrathin oxide layer is 1-1.8 nm, the thickness of the doped amorphous silicon layer is 80-130 nm, and the thickness of the outer mask layer silicon oxide is 10-50 nm.

[0060] Then, the doped sheet resistance is 30-80Ω / sq, and after annealing at 650-950℃, the doped amorphous silicon is crystallized into a doped polycrystalline silicon film.

[0061] Then, through the RCA process, the front side of the silicon wafer is etched and acid-washed in a chain, and the poly silicon winding plating on the edge and front side is removed by the tank RCA cleaning. The BSG layer on the front side is then removed by the HF acid tank cleaning.

[0062] A thin film of AlOx (aluminum oxide) with a thickness of 3-8 nm is deposited on the front surface using ALD (atomic layer deposition) technology;

[0063] Silicon nitride layers are deposited on both the front and back sides using a coating process. The thickness of the silicon nitride film on the front side is 60-90 nm, and the refractive index is 2.0-2.10. The thickness of the silicon nitride film on the back side is 70-90 nm, and the refractive index is 2.05-2.15.

[0064] Finally, silver paste is printed on both the front and back sides, and then laser-assisted sintering is used.

[0065] In another embodiment of the present invention, the side polishing step further includes a deionized water rinsing process, wherein after etching the cut surface with TMAH and IPA aqueous solutions, the cut surface is rinsed with deionized water.

[0066] In another embodiment of the present invention: the side polishing step further includes hydrofluoric acid treatment. After the cut surface is cleaned with deionized water, the roller 61 drives the battery panel 5 into the hydrofluoric acid bath to remove the silicon oxide from the cut surface of the battery.

[0067] The specific steps for side polishing are as follows: The battery is conveyed forward into the polishing tank in solution tank 2.1. Roller 61 drives the TMAH (tetramethylammonium hydroxide) + IPA (isopropanol) solution in the polishing tank to contact the bottom cut surface of the upright battery panel 5. The TMAH + IPA solution is used to etch and polish the silicon on the cut surface by utilizing its highly selective etching characteristics on silicon and silicon nitride. The mass fraction of the TMAH + IPA solution is 10-30% TMAH and 5-20% IPA, and the temperature of the TMAH + IPA solution is 30-60℃. At the same time, the middle battery panel 5 is etched and polished using inclined roller 61.1.

[0068] Next, rinse the cut surface of the battery with deionized water;

[0069] Roller 61 continues to convey the battery panel 5 forward to the HF tank (hydrofluoric acid tank). During the rotation of the roller 61 with liquid, the cut surface of the battery comes into contact with the HF solution on the roller 61 to remove the silicon oxide from the cut surface of the battery panel 5. The HF solution has a mass fraction of 5%-35% and a temperature of 20-30℃.

[0070] Finally, the lower surface of the battery is rinsed with deionized water, and the battery panel 5 is transported to a drying device for drying.

[0071] The electrical performance data of the solar cells with and without side polishing are as follows:

[0072] category Eta Uoc Isc FF IRev2 No side polishing 26.601 0.7320 7.1338 85.249 0.035 Side polishing 26.647 0.7332 7.1336 85.263 0.026

[0073] Notes: Battery conversion efficiency (Eta), open circuit voltage (Uoc), short circuit current (Isc), fill factor (FF), and reverse leakage current (IRev2);

[0074] A novel TOPCon battery polishing device includes a base 1 and a partition 3 and a guide block 4 fixedly mounted thereon, and further includes:

[0075] The rotating frame 66 is rotatably mounted at the upper middle position of the base 1;

[0076] Partition 3 is provided on both sides of the rotating frame 66;

[0077] Guide blocks 4 are disposed on both sides of the base 1, and the two guide blocks 4 are combined with the two partitions 3 in a one-to-one correspondence to form a guide groove;

[0078] Roller 61 is rotatably mounted in base 1, and solution tank 2.1 is provided on base 1, with roller 61 disposed in solution tank 2.1;

[0079] The drive mechanism drives the roller 61 to rotate to convey and polish the battery panel 5. While the roller 61 is rotating, it will drive the rotating frame 66 to swing back and forth so that the battery panel 5 above the rotating frame 66 can be polished on both sides.

[0080] The rollers 61 are provided in a plurality of manner, and each pair of adjacent rollers 61 is connected by a sprocket drive, so that when the drive mechanism drives one roller 61 to rotate, that roller 61 can drive another roller 61 to rotate via the sprocket, and the other roller in turn drives the next roller 61 to rotate, so that all rollers 61 can be driven. The drive mechanism is preferably a servo motor, which can drive one of the rollers 61 to rotate.

[0081] Furthermore, an inner block 2 is fixedly installed inside the base 1, and the inner wall of the base 1 is divided into two solution tanks 2.1 on the left and right sides by the inner block 2.

[0082] In another embodiment of the present invention: an arc-shaped rod 65 is fixedly installed at the bottom end of the rotating frame 66, and a connecting rod 64 is fixedly installed on the arc-shaped rod 65;

[0083] A connecting shaft 62 is fixedly installed on one of the rollers 61. A sliding frame 63 is threaded onto the connecting shaft 62. A groove 63.1 that matches the size of the connecting rod 64 is opened on the sliding frame 63. The connecting rod 64 is inserted into the groove 63.1.

[0084] The connecting shaft 62 has a bidirectional threaded groove, so that when the connecting shaft 62 rotates in only one direction, it can drive the sliding frame 63 on it to move back and forth. When the sliding frame 63 moves back and forth, it can drive the connecting rod 64 inside it to move. Since the connecting rod 64 is fixedly installed on the arc-shaped rod 65, it can drive the arc-shaped rod 65 to move.

[0085] In another embodiment of the present invention: the rotating frame 66 is composed of an outer frame and an intermediate rod 66.1. A rotating shaft 81 is fixedly installed on the outer frame, and a round rod 67 is fixedly installed between the intermediate rod 66.1 and the outer frame.

[0086] The rotating shaft 81 and the arc-shaped rod 65 are coaxially arranged. When the sliding frame 63 drives the connecting rod 64 to move, since the connecting rod 64 is fixed on the arc-shaped rod 65, the arc-shaped rod 65 will drive the rotating frame 66 to rotate through the rotating shaft 81, thereby realizing the left and right reciprocating swing.

[0087] Furthermore, the rotating frame 66 can be set into a plate shape so as not to leave a gap in the middle, so as to facilitate the sliding of the battery panel 5 on it.

[0088] In another embodiment of the present invention: a slanted wheel 61.1 is fixedly installed on one side of the roller 61;

[0089] The cross-section of the inclined wheel 61.1 is frustum-shaped;

[0090] When the servo motor drives the roller 61 to rotate, refer to Figure 5 The rotation of roller 61 will drive the connecting shaft 62 to rotate, and the connecting shaft 62 will drive the sliding frame 63 to move back and forth until it moves to the middle position. When the connecting rod 64 is at the bottom, the arc rod 65 will drive the rotating frame 66 to rotate to the horizontal position. The horizontally set rotating frame 66 allows the subsequent solar panel 5 to enter the rotating frame 66. After the solar panel 5 enters the rotating frame 66, the sliding frame 63 continues to move horizontally. At this time, the sliding frame 63 drives the connecting rod 64 to move to the left. The connecting rod 64 will drive the arc rod 65 to rotate clockwise to the left, so that the rotating frame 66 will be driven to rotate clockwise and tilt to the lower right. At this time, the solar panel 5 will slide to the lower right and contact the inclined wheel 61.1 on the right roller 61. At this time, as the roller 61 rotates, the inclined wheel 61.1 will also rotate and push the solar panel 5 to move forward.

[0091] refer to Figure 11 When the battery panel 5 slides down at an angle and comes into contact with the inclined side of the inclined wheel 61.1, the rotation of the inclined wheel 61.1 will push the battery panel 5 forward on the rotating frame 66.

[0092] The solution tank 2.1 is divided into a polishing tank and an HF tank (hydrofluoric acid tank). The polishing tank contains 10-30% TMAH and 5-20% IPA aqueous solution, while the HF tank contains 5%-35% HF solution. Two-thirds of the rollers 61 and slanted rollers 61.1 are located in the solution. When the rollers 61 rotate, their surfaces will carry the solution to corrode and polish the cut surface of the solar panel 5. At the same time, a deionized water tank is set between the polishing tank and the HF tank. The deionized water tank is equipped with nozzles to spray deionized water onto the surface of the solar panel 5 for cleaning.

[0093] In another embodiment of the present invention: a long shaft 83 is rotatably mounted on the base 1, and a rotating shaft 81 is rotatably mounted on the base 1, and a belt 82 is connected between the long shaft 83 and the rotating shaft 81 for transmission.

[0094] A slide rod 84 is horizontally slidably mounted on the base 1, with the long shaft 83 and the slide rod 84 in contact. A rotating bar 85 is rotatably mounted on the base 1, and a friction rod is fixedly mounted on the rotating bar 85, with the friction rod and the slide rod 84 in contact.

[0095] When the rotating frame 66 rotates, it drives the rotating shaft 81 to rotate. As the rotating shaft 81 rotates, it drives the sliding rod 84 to translate via the belt 82. When the sliding rod 84 translates, it drives the rotating bar 85 to rotate via the friction rod. (See reference...) Figure 5-6 The conveyor belt transports the battery to the front end of the base 1. When the battery panel 5 is in contact with the guide block 4, its movement will be restricted. At this time, as the rotating frame 66 continues to rotate, if it rotates clockwise, the slide bar 84 will move to the left. At this time, the left rotating bar 85 will be driven to rise. At this time, the left rotating bar 85 is located below the battery panel 5. As the left rotating bar 85 rises, it will drive the left side of the battery panel 5 to lift up. When the battery panel 5 is lifted up, it will enter the conveying channel 3.1 through the guide block 4 and be transported by the roller 61.

[0096] Furthermore, the long shaft 83 and the slide bar 84, as well as the friction bar and the slide bar 84, can be meshed together.

[0097] In another embodiment of the present invention: the guide block 4 includes an arc-shaped block and a long plate 4.1, and a conveying channel 3.1 is formed between the long plate 4.1 and the partition 3;

[0098] When the battery is laser-cut into three parts by a conveyor belt, the left and right side panels 5 have only one cut surface, while the middle panel 5 has two cut surfaces. During etching and polishing, to avoid significant impact of the solution on the surface of the panel 5, the cut surfaces are usually placed downwards. However, with two cut surfaces, conventional etching and polishing of the middle panel 5 requires operating on only one surface first, then returning it to the other side after the entire process is complete. This prolongs the polishing process and also makes it easy to miss some panels 5 that have only one side polished. In this application, after the slicing operation, the middle panel 5 with two cut surfaces can be etched and polished by swinging it left and right, allowing one cut surface to face downwards first, and then the other side to face downwards. This polishing process is simple and can be performed continuously. Furthermore, during the tilting of the middle panel 5, the rotation of the rotating frame 66 drives the two rotating bars 85 to rotate, lifting the side panels 5 and passively allowing them to stand upright for etching. (See reference...) Figure 5When the left rotating bar 85 lifts the left battery panel 5, the arc-shaped block in the guide block 4 guides the tilted and standing left battery panel 5 into the conveying channel 3.1 and makes it stand up completely so that the cut surface faces down.

[0099] In another embodiment of the present invention: the surface of the rotating frame 66 is provided with a chamfer 66.2;

[0100] When the rotating frame 66 is in a horizontal state, the chamfer 66.2 makes it easier for the middle battery panel 5 to enter the top of the rotating frame 66.

[0101] In another embodiment of the present invention: a friction wheel 71 and a rotating wheel 73 are rotatably mounted on the arc-shaped rod 65, wherein the friction wheel 71 extends from the bottom end of the arc-shaped rod 65, and a transmission belt 72 is provided between the friction wheel 71 and the rotating wheel 73;

[0102] A rotating rod 74 is rotatably mounted on the arc rod 65, and a first bevel gear 75 is fixedly mounted on both ends of the rotating rod 74. A round bar 76 is rotatably mounted inside the middle rod 66.1. A second bevel gear 77 is fixedly mounted on the round bar 76, and a fan blade 78 is fixedly mounted on the round bar 76.

[0103] The round rod 67 is hollow, and several through holes are provided on the outer frame;

[0104] The inner block 2 is provided with an arc-shaped groove to facilitate the rotation of the arc-shaped rod 65. When the arc-shaped rod 65 rotates, the friction wheel 71 extends from its surface and can rotate by friction with the arc-shaped groove on the inner block 2. At this time, the friction wheel 71 will drive the rotating wheel 73 to rotate through the transmission belt 72. The rotating wheel 73 will drive the rotating rod 74 to rotate through the first bevel gear 75 below the rotating rod 74. The first bevel gear 75 and the second bevel gear 77 at the upper end of the rotating rod 74 will drive the round bar 76 to rotate. The rotating wheel 73 is also equipped with a connecting bevel gear to mesh with the first bevel gear 75 below the rotating rod 74. When the round bar 76 rotates, it will drive the fan blade 78 to rotate. At this time, the fan blade 78 will blow air through the hollow round rod 67 and the through hole on the outer frame.

[0105] Several through holes are connected to the round rod 67 in a one-to-one correspondence. When the rotating frame 66 tilts so that the solar panel 5 on it contacts the inclined wheel 61.1, as the rotating frame 66 rotates upward to drive the corroded end of the solar panel 5 to rise, the corroded liquid on it is easily carried up and flows on the surface of the solar panel 5 as the other end of the solar panel 5 tilts. (Reference) Figure 5 If the solar panel 5 tilts to the lower left as the rotating frame 66 rotates, the right side will lift up. At this time, the fan blade 78 on the right side will blow air towards the right side of the rotating frame 66, thereby blowing away the corrosive liquid at the bottom right side of the solar panel 5, and working with the rotating frame 66 itself to greatly reduce the residue of the corrosive liquid.

[0106] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A novel TOPCon battery fabrication process, characterized in that, Includes the following steps: S1, Production; S2, Segmentation: Using a laser to divide the entire cell into sections; S3. Side polishing: Chain etching of alkaline washing of the cut surface, using 10-30% TMAH and 5-20% IPA aqueous solution, etching the cut surface at 30-60℃. S4. Edge passivation: Deposit a 20-50 nm aluminum oxide passivation film using atomic layer deposition, and anneal at 250-300℃ for 30-60 min. S5 and IV tests: The cells are graded after testing their appearance, IV and EL performance.

2. The novel TOPCon battery fabrication process according to claim 1, characterized in that, The wafer fabrication process includes texturing and boron diffusion. The texturing process uses an N-type monocrystalline silicon wafer as the substrate and uses acid and alkali chemicals to texturize both sides of the monocrystalline silicon wafer to form a pyramid structure on the surface of the monocrystalline silicon wafer. In the boron diffusion process, the boron source is BCl3.

3. The novel TOPCon battery fabrication process according to claim 1, characterized in that, The side polishing step also includes a deionized water rinsing process, in which the cut surface is rinsed with deionized water after etching the cut surface with TMAH and IPA aqueous solutions.

4. The novel TOPCon battery fabrication process according to claim 1, characterized in that, The side polishing step also includes hydrofluoric acid treatment. After the cut surface is cleaned with deionized water, the roller (61) drives the battery panel (5) into the hydrofluoric acid bath to remove the silicon oxide from the cut surface of the battery.

5. A novel TOPCon battery polishing device, applicable to the battery manufacturing process according to any one of claims 1-4, comprising a base (1) and a separator (3) and a guide block (4) fixedly mounted thereon, characterized in that, Also includes: The rotating frame (66) is rotatably mounted at the middle position above the base (1); Partition (3) is set on both sides of the rotating frame (66); Guide blocks (4) are set on both sides of the base (1), and the two guide blocks (4) are combined with the two partitions (3) respectively to form a guide groove; A roller (61) is rotatably mounted in a base (1), and a solution tank (2.1) is provided on the base (1). The roller (61) is located in the solution tank (2.1). The drive mechanism drives the roller (61) to rotate to convey and polish the battery panel (5), and while the roller (61) rotates, it drives the rotating frame (66) to swing back and forth so that the battery panel (5) above the rotating frame (66) can be polished on both sides.

6. The novel TOPCon battery polishing device according to claim 5, characterized in that, An arc-shaped rod (65) is fixedly installed at the bottom of the rotating frame (66), and a connecting rod (64) is fixedly installed on the arc-shaped rod (65). A connecting shaft (62) is fixedly installed on one of the rollers (61). A sliding frame (63) is threaded onto the connecting shaft (62). A sliding groove (63.1) adapted to the size of the connecting rod (64) is opened on the sliding frame (63). The connecting rod (64) is inserted into the sliding groove (63.1).

7. A novel TOPCon battery polishing device according to claim 5, characterized in that, The rotating frame (66) consists of an outer frame and an intermediate rod (66.1). A rotating shaft (81) is fixedly installed on the outer frame, and a round rod (67) is fixedly installed between the intermediate rod (66.1) and the outer frame.

8. A novel TOPCon battery polishing device according to claim 5, characterized in that, A slant wheel (61.1) is fixedly installed on one side of the roller (61).

9. A novel TOPCon battery polishing device according to claim 5, characterized in that, A long shaft (83) is rotatably mounted on the base (1), and a rotating shaft (81) is rotatably mounted on the base (1), and a belt (82) is connected between the long shaft (83) and the rotating shaft (81). A slide rod (84) is horizontally slidably mounted on the base (1). The long shaft (83) and the slide rod (84) are in contact with each other. A rotating bar (85) is rotatably mounted on the base (1). A friction rod is fixedly mounted on the rotating bar (85), and the friction rod and the slide rod (84) are in contact with each other.

10. A novel TOPCon battery polishing device according to claim 5, characterized in that, The guide block (4) includes an arc-shaped block and a long plate (4.1), and a conveying channel (3.1) is formed between the long plate (4.1) and the partition (3).

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