A discharge structure for an edge passivation reactor

Abstract

The utility model discloses a kind of discharge structures of edge passivation reaction equipment, the edge passivation reaction equipment includes the furnace body with reaction furnace tube being internally equipped, and the both ends of reaction furnace tube are equipped with gas inlet and air outlet respectively, the discharge structure is arranged in reaction furnace tube, the discharge structure includes mutually insulated and opposite potential first electrode plate assembly and second electrode plate assembly, battery piece is placed on first electrode plate assembly;When power is turned on, alternating electric field is formed between the cutting surface of battery piece and second electrode plate assembly, so that process gas in reaction furnace tube ionizes to form plasma, realize the edge passivation of battery piece.The utility model has the characteristics of compact structure, high safety and high reliability, improves the efficiency of the edge passivation of battery piece, and can take into account the edge passivation demand of half piece and multiple piece.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic cell manufacturing technology, specifically to a discharge structure for an edge passivation reaction device. Background Technology

[0002] The use of half-cell modules for module encapsulation has become mainstream in the photovoltaic industry. Manufacturing modules with half-cells offers numerous advantages, including reduced module current, lower resistance losses, higher module voltage, and increased module output power. As the power requirements for modules become increasingly stringent, three-cell and four-cell technologies have emerged based on half-cell technology. Current multi-cell technologies mainly fall into two categories: one involves slicing the silicon wafer at the wafer end, with subsequent processes using half-cell or multi-cell production. This approach, limited by automation and screen printing, has a relatively large impact on production capacity. The other involves producing the entire wafer first, followed by laser slicing after cell fabrication, which has a relatively smaller impact on production capacity. Because the second half-cell technology requires slicing the entire cell, the cutting process can damage the edges, leading to increased edge recombination. This affects parameters such as open-circuit voltage (Voc) and fill factor (FF), ultimately reducing cell efficiency. Edge passivation technology was developed to address this issue by passivating the cut edges, repairing damage, and restoring the cell's performance.

[0003] Currently, edge passivation technology for half-cell batteries is relatively mature. The mainstream approach for half-cell passivation technology in the market is to use ALD (Alternating Deposition) to deposit alumina to passivate the cut surface. There are also PECVD (Pure Chemical Vapor Deposition) and HWCVD (Hot Wire Vapor Deposition) technologies for edge passivation.

[0004] The temperature range for ALD (Atomic Layer Deposition) alumina deposition is typically 150-300℃. The alumina then requires annealing to achieve optimal passivation. If the annealing temperature is too low, the passivation effect will be weakened; if the annealing temperature is too high, it will affect other aspects of battery performance. Furthermore, the thicker the alumina layer, the higher the annealing temperature and time need to be. Secondly, because ALD technology is an atomic layer deposition technique, deposition is self-limiting, resulting in a relatively slow deposition rate. ALD processes are also time-consuming, and gas consumption costs are higher than PECVD. PECVD technology offers shorter processing times and lower gas consumption, resulting in slightly lower overall operating costs compared to ALD. However, existing PECVD technologies require consideration of discharge, making the process more complex than ALD.

[0005] In addition, existing ALD and PECVD technologies are mostly designed for the edge passivation of half a cell (one cut edge). If the existing technology is used, one side needs to be passivated first, and then the cell direction needs to be turned over to passivate the other side. This requires increased automation and has a long process time, which has a certain impact on production capacity, cell efficiency and yield. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a discharge structure for an edge passivation reaction device that is compact, easy to operate, highly stable, and conducive to improving production capacity, in order to address the shortcomings of the existing technology.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: A discharge structure for an edge passivation reaction device is disclosed. The edge passivation reaction device includes a furnace body with an internal reaction furnace tube. The two ends of the reaction furnace tube are respectively provided with an air inlet and an air outlet. The discharge structure is disposed inside the reaction furnace tube and includes a first electrode plate assembly and a second electrode plate assembly that are mutually insulated and have opposite potentials. A solar cell is placed on the first electrode plate assembly. When the power is turned on, an alternating electric field is formed between the cut surface of the solar cell and the second electrode plate assembly, causing the process gas inside the reaction furnace tube to ionize and form plasma, thereby achieving edge passivation of the solar cell.

[0008] As a further improvement of this utility model, the first electrode plate assembly includes a material box and an electrode rod, the battery cell is placed in the material box, and the electrode rod is used to connect the material box to an external power source.

[0009] As a further improvement of this utility model, the second electrode plate assembly includes a boat support and a seat electrode, wherein the seat electrode is used to connect the boat support to an external power source; a plurality of the material boxes are placed side by side inside the boat support, with the cut surface of the battery cell facing the inner wall of the boat support.

[0010] As a further improvement of this utility model, an insulating plate is provided between the material box and the boat support.

[0011] As a further improvement of this utility model, a conductive connector is provided between two adjacent material boxes for electrical connection.

[0012] As a further improvement of this utility model, the bottom of the boat support is provided with a through hole to allow the process gas in the reactor tube to flow upward and downward within the boat support.

[0013] As a further improvement of this utility model, a support rod is provided inside the reactor tube, and the boat support is placed on the support rod.

[0014] As a further improvement of this utility model, the seat electrode is nested on the support rod and makes conductive contact with the bottom of the boat support.

[0015] As a further improvement of this utility model, the front and rear sides of the material box are through structures so that the cut surface of the battery cell faces the inner wall of the boat support. The left and right sides and the top and bottom sides of the material box are provided with cover plates.

[0016] As a further improvement of this utility model, the interior of the boat support is divided into two identical placement slots.

[0017] Compared with the prior art, the advantages of this utility model are: The discharge structure of the edge passivation reaction device of this utility model uses the material box and the boat support as two discharge electrode plates respectively, and places the battery cell between the two discharge electrode plates with the cut edge of the battery cell facing the inner side wall of the boat support. The battery cell also serves as an electrode. Combined with the structural design of the material box, it achieves uniform coating on both sides of the cut edge of the battery cell at the same time, which greatly improves the production capacity and reduces the cost. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the main structural principle of the discharge structure of the edge passivation reaction device in a specific embodiment of this utility model; Figure 2 This is a top view schematic diagram of the discharge structure of the edge passivation reaction device in a specific embodiment of this utility model; Figure 3 This is a schematic diagram of the airflow inside the discharge structure of the edge passivation reaction device in a specific embodiment of this utility model; Figure 4 This is a schematic diagram of the discharge structure in a specific embodiment of the present invention; Figure 5 This is a schematic diagram of the discharge structure from another perspective in a specific embodiment of this utility model; Figure 6 This is a schematic diagram of the discharge structure installed inside the reactor tube in a specific embodiment of the present invention; Legend: 1. Furnace door; 2. Furnace body; 3. Heater; 4. Furnace tube; 5. Spray plate; 6. Material box; 7. Boat support; 71. Through hole; 8. Furnace tail flange; 9. Electrode rod; 10. Baffle; 11. Support rod; 12. Insulating plate; 13. Conductive connector; 14. Base electrode; 100. Battery cell. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0020] In the description of this utility model, it should be understood that the terms "side", "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0022] Example like Figure 1 and Figure 2 As shown, the discharge structure of this utility model is installed inside an edge passivation reaction device. The edge passivation reaction device includes a furnace body 2 with a reaction furnace tube 4 inside. A heater 3 is arranged around the outer wall of the reaction furnace tube 4 to heat the reaction furnace tube 4 and maintain the temperature required for the process. A furnace door 1 and a furnace tail flange 8 are respectively provided at both ends of the furnace body 2. The furnace door 1 isolates the reaction furnace tube 4 from the external environment. The air inlet is located at the furnace opening of the reaction furnace tube 4, and the air extraction port of the reaction furnace tube 4 is located on the furnace tail flange 8. The air extraction port is connected to a vacuum pump through a pipeline to evacuate the reaction furnace tube 4 and maintain stable process pressure. A spray plate 5 is provided above the reaction furnace tube 4, and the spray plate 5 is connected to the air inlet to achieve uniform diffusion of the process gas through the spray plate 5 before it is distributed from top to bottom into the reaction furnace tube 4, extending the flow path of the process gas and further improving the uniformity of process gas distribution. Meanwhile, a solid baffle 10 is provided at the end of the reactor tube 4, and the baffle 10 is located at the front end of the exhaust port and the tail flange 8. The bottom of the baffle 10 has a notch to improve the flow direction of the process gas, so that the process gas is sprayed in from above the reactor tube 4 and drawn out from below the cavity of the reactor tube 4 towards the tail, thus extending the flow path of the process gas in the reactor tube 4 and increasing the uniformity of the process gas distribution. In this embodiment, the spray plate 5 can adopt a conventional configuration in the art. For example, the spray plate 5 can be a hollow cavity with multiple spray holes at the bottom, fixed above the reactor tube 4 by a bracket. One end of the cavity is connected to the exhaust port, and the process gas flows into the hollow cavity and then diffuses into the reactor tube 4 through the spray holes.

[0023] In this embodiment, the discharge structure is disposed inside the reactor tube 4. The discharge structure includes a first electrode plate assembly and a second electrode plate assembly that are insulated from each other and have opposite potentials. The battery cell 100 is placed on the first electrode plate assembly, and together with the first electrode plate assembly, they form a discharge electrode plate. When the power is turned on, the battery cell 100 and the first electrode plate assembly have the same potential. An alternating electric field is formed between the cut surface of the battery cell 100 and the second electrode plate assembly, causing the process gas inside the reactor tube 4 to ionize and form plasma, thereby achieving edge passivation of the battery cell 100.

[0024] like Figure 1 and Figure 3 As shown, the first electrode plate assembly includes a material box 6 and an electrode rod 9. The cut battery cells 100 are stacked in the material box 6, and the electrode rod 9 is installed through the furnace tail flange 8 to enable the material box 6 to be connected to an external power source.

[0025] like Figure 1 and Figure 3 As shown, the second electrode plate assembly includes a boat support 7 and a seat electrode 14. The seat electrode 14 is connected to the outside of the reactor tube 4 via a conductive cable to enable the boat support 7 to be connected to an external power source. Multiple material boxes 6 are placed side by side inside the boat support 7, and the cut surface of the battery cell 100 faces the inner wall of the boat support 7 to discharge and form plasma.

[0026] Furthermore, the front and rear sides of the material box 6 facing the boat support 7 have an unobstructed through-structure to ensure that the cut surface of the battery cell 100 discharges with the inner wall of the boat support 7; while the left and right sides and the top and bottom sides of the material box 6 have shielding plates, and a cover plate is provided above the battery cell 100 to prevent plating from appearing on the front side of the battery cell 100. Figure 4 , Figure 5 and Figure 6 As shown, the interior of the boat support 7 is divided into two identical placement slots. Multiple material boxes 6 can be placed side by side in both slots, which can accommodate more solar cells 100 for edge passivation, significantly improving the production efficiency of solar cells 100.

[0027] like Figure 1 As shown, an insulating plate 12 made of alumina ceramic is provided between the material box 6 and the boat support 7 to prevent the battery cell 100 from contacting the boat support 7 and causing conductivity. A conductive connector 13 is provided between two adjacent material boxes 6 for electrical connection. The conductive connector 13 can be a conductive rod or a conductive wire, as long as it can achieve electrical connection between two adjacent material boxes 6 and have the same potential.

[0028] like Figure 4 As shown, the bottom of the boat support 7 is provided with a through hole 71. The process gas sprayed in by the spray plate 5 flows into the boat support 7, is ionized, and then flows through the through hole 71 to the exhaust port and is then discharged from the reactor tube 4.

[0029] In this embodiment, the material box 6 and the boat support 7 serve as two discharge electrode plates, respectively. The battery cell 100 is placed inside the material box 6, positioned between the two discharge electrode plates, with the cut edges of the battery cell 100 facing the inner wall of the boat support 7. The battery cell 100 also serves as an electrode. Gas is sprayed in from above the reactor tube 4 and drawn out from below, allowing the process gas to flow evenly into the boat support 7. Combined with the structural design of the material box 6, this achieves simultaneous and uniform coating of the cut edges on both sides of the battery cell 100, significantly improving production capacity and reducing costs. By using a spray-in method from above the reactor tube 4, and since the spray plate 5 does not participate in the discharge, clogging of the spray plate 5 is avoided, eliminating the need for frequent cleaning and maintenance of the air inlet.

[0030] like Figure 1 As shown, a support rod 11 is provided inside the reactor tube 4, and the boat support 7 is placed on the support rod 11. Multiple seat electrodes 14 are nested on the support rod 11 and are in conductive contact with the bottom of the boat support 7, and adjacent seat electrodes 14 are electrically connected by conductive components.

[0031] In this embodiment, the technical route of depositing a passivation layer on the side of stacked solar cells using PECVD can be directly modified based on existing coating equipment. By optimizing the discharge structure inside the reactor tube 4, passivation layer coating can be applied to the edges of single / double-cut solar cells, achieving better passivation. Furthermore, by simply changing the process gas source, it can simultaneously accommodate PECVD deposition of passivation films such as silicon nitride, silicon oxide, and amorphous silicon, as well as PEALD deposition of alumina, thus effectively meeting the passivation requirements of half-cell or multi-cell solar cells.

[0032] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A discharge structure for an edge passivation reaction device, characterized in that, The edge passivation reaction equipment includes a furnace body (2) with a reaction furnace tube (4) inside, and the two ends of the reaction furnace tube (4) are respectively provided with an air inlet and an air outlet. The discharge structure is set inside the reaction furnace tube (4). The discharge structure includes a first electrode plate assembly and a second electrode plate assembly that are mutually insulated and have opposite potentials. The battery cell (100) is placed on the first electrode plate assembly. When the power is turned on, an alternating electric field is formed between the cut surface of the battery cell (100) and the second electrode plate assembly, which ionizes the process gas in the reaction furnace tube (4) to form plasma, thereby achieving edge passivation of the battery cell (100).

2. The discharge structure of the edge passivation reaction device according to claim 1, characterized in that, The first electrode plate assembly includes a material box (6) and an electrode rod (9). The battery cell (100) is placed inside the material box (6), and the electrode rod (9) is used to connect the material box (6) to an external power source.

3. The discharge structure of the edge passivation reaction device according to claim 2, characterized in that, The second electrode plate assembly includes a boat support (7) and a seat electrode (14), the seat electrode (14) being used to connect the boat support (7) to an external power source; a plurality of the material boxes (6) are placed side by side inside the boat support (7), with the cut surface of the battery cell (100) facing the inner wall of the boat support (7).

4. The discharge structure of the edge passivation reaction device according to claim 3, characterized in that, An insulating plate (12) is provided between the material box (6) and the boat support (7).

5. The discharge structure of the edge passivation reaction device according to claim 3, characterized in that, A conductive connector (13) is provided between two adjacent material boxes (6) for electrical connection.

6. The discharge structure of the edge passivation reaction device according to claim 3, characterized in that, The bottom of the boat support (7) is provided with a through hole (71) to allow the process gas in the reactor tube (4) to flow in and out of the boat support (7).

7. The discharge structure of the edge passivation reaction device according to any one of claims 3 to 6, characterized in that, The reactor tube (4) is provided with a support rod (11), and the boat support (7) is placed on the support rod (11).

8. The discharge structure of the edge passivation reaction device according to claim 7, characterized in that, The seat electrode (14) is nested on the support rod (11) and makes conductive contact with the bottom of the boat support (7).

9. The discharge structure of the edge passivation reaction device according to any one of claims 3 to 6, characterized in that, The front and rear sides of the material box (6) are through structures so that the cut surface of the battery cell (100) faces the inner wall of the boat support (7). The left and right sides and the top and bottom sides of the material box (6) are provided with cover plates.

10. The discharge structure of the edge passivation reaction device according to any one of claims 3 to 6, characterized in that, The boat support (7) is internally divided into two identical placement slots.

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