Electroplating method of TBC battery
The electrode pattern on the back of the TBC battery is formed by laser groove and activator treatment, and combined with nickel and copper plating, the problem of large material loss in traditional electroplating methods is solved, and a low-cost electroplating process is realized.
Patent Information
- Application Number
- CN202311784621.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-23
- Publication Date
- 2025-07-04
AI Technical Summary
The electroplating method of traditional TBC batteries has led to an increase in silver consumption and high cost, which makes it impossible to achieve large-scale mass production. The existing electroplating process materials are large and the manufacturing cost is high.
Laser grooves are used to form the back electrode pattern, and the grooved area is activated with an activator. After forming a nickel layer, the sintering process is carried out to form ohmic contacts. Then copper plating is performed to reduce copper loss and avoid the use of masks and acid corrosion steps.
Reduces material and environmental protection costs, simplifies process steps, reduces copper losses, reduces manufacturing costs, and realizes a simpler electroplating process.
Smart Images
Figure CN120250105A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of solar cells, and in particular relates to a plating method for TBC cells. Background Art
[0002] The TBC cell is a photovoltaic cell based on organic semiconductor materials, with characteristics such as high conversion efficiency, low manufacturing cost, light weight, thinness, and flexibility, and is regarded as one of the important development directions of the future photovoltaic industry.
[0003] Since the metallization area on the back of the TBC cell is very high, accounting for about 30% of the area, if the traditional method of printing silver paste is used, it will lead to an increase in silver consumption and a significant increase in the cost of the cell, making large-scale mass production impossible.
[0004] Currently, the traditional plating method for TBC cells is to first deposit a thin nickel layer on the entire surface by PVD, then deposit a thin copper layer on the entire surface by PVD, and then thicken the metal electrodes on the entire surface to 8 - 10 μm by electroplating. Then, an acid-resistant mask is printed, and the area not covered by the mask is washed away with acid. After removing the mask, the metal electrodes required for the pattern are retained, resulting in a large amount of material loss and high manufacturing cost. Summary of the Invention
[0005] In view of the above problems, the present invention provides a plating method for TBC cells to solve the above or other previous problems existing in the prior art.
[0006] To solve the above technical problems, the technical solution adopted by the present invention is: a plating method for TBC cells, comprising the following steps:
[0007] Grooves are formed on the back of the TBC cell to form a back electrode pattern;
[0008] The grooved area of the cell is activated;
[0009] Nickel treatment is performed on the activated grooved area to form a nickel layer in the grooved area;
[0010] The cell after nickel treatment is sintered to make silicon and nickel form an ohmic contact;
[0011] The sintered cell is electroplated to increase the thickness of the metal electrodes.
[0012] Further, in the step of activating the grooved area of the cell, an activator is used to activate the grooved area of the cell, and the activator includes, but is not limited to, a palladium-containing activator, a gold-containing activator, a silver-containing activator, or a silicon-containing activator.
[0013] Further, in the step of nickel-treating the activated grooved area to form a nickel layer in the grooved area, the grooved area of the battery is nickel-treated with a nickel solution, which includes nickel sulfate, sulfuric acid, ammonia water, hydroxycarboxylic acid, sodium hypophosphite, and sodium hydroxide. The mass percentages of nickel sulfate, sulfuric acid, ammonia water, hydroxycarboxylic acid, sodium hypophosphite, and sodium hydroxide are 30-70:10-30:3-15:3-15:1-10:1-15.
[0014] Further, before activating the grooved area of the battery wafer, the grooved area of the battery wafer is pickled to remove the oxide layer in the grooved area.
[0015] Further, when pickling the grooved area, the battery wafer is cleaned with an acid solution. The concentration of the acid solution is 1-10%, and the acid solution is an inorganic acid, which includes but is not limited to hydrofluoric acid, hydrochloric acid, sulfuric acid, nitric acid, or phosphoric acid.
[0016] Further, in the step of forming the back electrode pattern by grooving on the back of the TBC battery wafer, a laser is used for grooving to expose the POLY in the electroplating area on the back of the battery.
[0017] Further, in the step of sintering the nickel-treated battery wafer to form an ohmic contact between silicon and nickel, the nickel-treated battery wafer is sintered in an oxygen-free environment, and the sintering temperature is 300-500 °C.
[0018] Further, in the step of electroplating the sintered battery wafer to increase the thickness of the metal electrode, the battery wafer is copper electroplated.
[0019] Further, it also includes performing an antioxidant treatment on the electroplated battery wafer.
[0020] Further, when performing the antioxidant treatment on the electroplated battery wafer, a copper antioxidant is used for the treatment.
[0021] Due to the adoption of the above technical solution, laser grooving is performed on the back of the TBC battery wafer to form an electrode pattern, eliminating the need for a mask, reducing material and environmental protection costs. The battery wafer is placed in an activator to activate the grooved area, and the activated battery wafer is nickel-treated to form a nickel layer on the exposed POLY part in the grooved area. The process is simpler than PVD nickel in the prior art. After sintering the nickel-treated battery wafer, copper electroplating is carried out, eliminating the need for acid etching back, reducing copper loss, and lowering the process cost. The overall process steps are simpler. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 is a flowchart of an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0023] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.
[0024] Figure 1 The flowchart of an embodiment of the present invention is shown. This embodiment relates to a plating method for a TBC battery, which is used for plating a TBC battery wafer, especially for plating the back surface of the TBC battery wafer. After grooving the battery wafer, activation, nickel treatment, and plating are carried out, so that the plating process steps of the TBC battery are reduced, the material loss is reduced, and the manufacturing cost is lowered.
[0025] A plating method for a TBC battery, as Figure 1 shown, includes the following steps:
[0026] Grooving is carried out on the back surface of the TBC battery wafer to form a back electrode pattern: In this step, a laser is used for grooving, and the silicon nitride on the back surface of the TBC battery wafer is grooved. During the grooving process, grooving is carried out according to the back electrode pattern of the battery wafer, so that after grooving, a back electrode pattern of the battery wafer is formed, and POLY in the area to be plated on the battery back is exposed during the process of completing the back electrode pattern of the battery wafer; in this embodiment, the picosecond laser. When performing laser grooving, the single-pulse energy of the laser is 10 uj - 10 mj.
[0027] The grooved battery is pickled to remove the oxide layer in the grooved area: After the battery wafer is grooved, the battery wafer is cleaned, mainly the grooved area on the battery wafer. When cleaning the grooved area, the battery wafer is cleaned with an acid solution to clean the oxide layer in the grooved area. This oxide layer is silicon oxide. Therefore, in this embodiment, preferably, the concentration of the acid solution is 1 - 10%, the acid solution is an inorganic acid, and the inorganic acid can be hydrofluoric acid, hydrochloric acid, sulfuric acid, nitric acid, or phosphoric acid. The pickling time is 30 - 120 s;
[0028] The grooved area with the oxide layer removed is activated: Organic polymer PdS adsorbs on silicon nitride and then displaces with nickel. After pickling the grooved area of the battery wafer, the grooved area is activated. An activator is used to activate the grooved area of the battery. When activating, the whole battery wafer is immersed in the activator so that the grooved area is fully in contact with the activator to activate the grooved area. In this embodiment, the activator can be a palladium-containing activator, such as palladium sulfate, or a gold-containing activator, a silver-containing activator, or a silicon-containing activator. The activation time is 30 - 120 s;
[0029] Perform nickel treatment on the activated grooved area to form a nickel layer in the grooved area: Use a nickel solution to perform nickel treatment on the grooved area of the battery. When performing nickel treatment, immerse the activated battery wafer in the nickel solution. Utilizing the selectivity of nickel, a layer of nickel is plated on the exposed POLY part in the grooved area to form a nickel layer, and no nickel will grow in other areas, so as to ensure that a nickel layer is formed in the grooved area during the nickel treatment process. In this embodiment, preferably, the nickel solution includes nickel sulfate, sulfuric acid, ammonia water, hydroxycarboxylic acid, sodium hypophosphite, and sodium hydroxide, and the mass percentages of nickel sulfate, sulfuric acid, ammonia water, hydroxycarboxylic acid, sodium hypophosphite, and sodium hydroxide are 30 - 70:10 - 30:3 - 15:3 - 15:1 - 10:1 - 15, and the nickel treatment time is 2 - 4 min;
[0030] Perform sintering treatment on the battery wafer after nickel treatment to make silicon and nickel form an ohmic contact: Perform nickel treatment on the battery wafer after nickel treatment in an anaerobic sintering furnace. Place the battery wafer after nickel treatment in the anaerobic sintering furnace and perform anaerobic sintering on the battery wafer after nickel treatment to make silicon and nickel form an ohmic contact. In this embodiment, the sintering temperature is 300 - 500 °C, and the sintering temperature can be 300 °C, 400 °C, 500 °C, or any sintering temperature between 300 - 500 °C, which is selected according to actual needs and no specific requirements are made here, and the sintering time is 1 - 6 min;
[0031] Perform electroplating on the sintered battery wafer to increase the thickness of the metal electrode: When performing electroplating on the battery wafer, perform copper electroplating on the battery wafer to thicken the metal electrode on the entire surface of the battery wafer to the required thickness, and the thickness of the metal electrode is selected according to actual needs and no specific requirements are made here;
[0032] Perform antioxidant treatment on the electroplated battery wafer: Immerse the electroplated battery wafer in a copper antioxidant for antioxidant treatment. The copper antioxidant is a copper protection agent, which can react with copper to form a protective film to prevent copper from being oxidized, and the antioxidant treatment time is 2 - 4 min.
[0033] Due to adopting the above technical solution, laser grooving is performed on the back of the TBC battery wafer to form an electrode pattern without the need to use a mask, reducing material and environmental protection costs. Place the battery wafer in an activator to activate the grooved area, and perform nickel treatment on the activated battery wafer to form a layer of nickel on the exposed POLY part in the grooved area. The process is simpler than PVD nickel in the prior art. After the battery wafer after nickel treatment is sintered, copper electroplating is performed without the need for acid etching, reducing copper loss and lowering the process cost, and the overall process steps are simpler.
[0034] The above has described the embodiments of the present invention in detail, but the above content is only the preferred embodiments of the present invention and cannot be considered as defining the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of the application of the present invention shall still fall within the scope covered by the patent of the present invention.
Claims
1. An electroplating method for a TBC battery, characterized in that: It includes the following steps: Grooves are formed on the back of the TBC cell to form a back electrode pattern; The grooved area of the cell is activated; Nickel treatment is performed on the activated grooved area to form a nickel layer in the grooved area; The cell after nickel treatment is sintered so that silicon and nickel form an ohmic contact; The sintered cell is electroplated to increase the thickness of the metal electrode.
2. The electroplating method of the TBC battery according to claim 1, characterized in that: In the step of activating the grooved area of the cell, an activator is used to activate the grooved area of the cell, and the activator includes but is not limited to a palladium-containing activator, a gold-containing activator, a silver-containing activator, or a silicon-containing activator.
3. The electroplating method of the TBC battery according to claim 1 or 2, characterized in that: In the step of performing nickel treatment on the activated grooved area to form a nickel layer in the grooved area, a nickel solution is used to perform nickel treatment on the grooved area of the cell. The nickel solution includes nickel sulfate, sulfuric acid, ammonia water, hydroxycarboxylic acid, sodium hypophosphite, and sodium hydroxide. The mass percentages of nickel sulfate, sulfuric acid, ammonia water, hydroxycarboxylic acid, sodium hypophosphite, and sodium hydroxide are 30-70:10-30:3-15:3-15:1-10:1-15.
4. The electroplating method of the TBC battery according to claim 3, characterized in that: Before activating the grooved area of the cell, pickling is performed on the grooved area of the cell to remove the oxide layer in the grooved area.
5. The electroplating method of the TBC battery according to claim 4, characterized in that: When pickling the grooved area, the cell is cleaned with an acid solution. The concentration of the acid solution is 1-10%, and the acid solution is an inorganic acid. The inorganic acid includes but is not limited to hydrofluoric acid, hydrochloric acid, sulfuric acid, nitric acid, or phosphoric acid.
6. The electroplating method of the TBC battery according to claim 1 or 2 or 4 or 5, characterized in that: In the step of forming grooves on the back of the TBC cell to form a back electrode pattern, a laser is used for grooving so that the POLY in the electroplated area on the back of the cell is exposed.
7. The electroplating method of the TBC battery according to claim 6, wherein: In the step of sintering the cell after nickel treatment so that silicon and nickel form an ohmic contact, the cell after nickel treatment is sintered in an oxygen-free environment, and the sintering temperature is 300-500 °C.
8. The electroplating method of the TBC battery according to any one of claims 1-2, 4-5 and 7, characterized in that: In the step of electroplating the sintered cell to increase the thickness of the metal electrode, copper electroplating is performed on the cell.
9. The electroplating method of the TBC battery according to claim 1, characterized in that: It also includes performing an antioxidant treatment on the electroplated cell.
10. The electroplating method of the TBC battery according to claim 9, characterized in that: When performing an antioxidant treatment on the electroplated cell, a copper antioxidant is used for treatment.