A process using peelable blue glue as electroplating seed layer

Abstract

The present invention relates to the field of photovoltaic cell manufacturing, specifically a process using a strippable blue glue as an electroplating seed layer, the present invention includes uniformly coating a 5-50 micron strippable blue glue on the surface of an HJT cell and curing it to form a seed layer, placing it in a copper electroplating solution, optimizing electroplating parameters according to cell characteristics to deposit copper ions to form grid lines, stripping the blue glue by physical or chemical methods after electroplating without residue and recyclable, and finally cleaning and drying the cell surface and performing electrical and reliability tests. This process has many advantages, compared with the traditional silver electrode process, the cost is reduced, the blue glue allows the copper grid line to be quickly formed to improve production efficiency, it is easy to strip to ensure cell performance, and the recyclability of the blue glue reflects environmental protection, and has good application prospects in the field of photovoltaic cell manufacturing.

Description

Technical Field

[0001] The invention relates to the field of photovoltaic cell manufacturing, in particular to a process using a strippable blue glue as an electroplating seed layer. Background Art

[0002] HJT solar cells have gradually become an important research direction in the field of solar cells due to their high efficiency and low temperature process. The production of HJT cells usually involves forming a thin film structure on the surface of a silicon wafer and depositing metallized grid lines on it. Traditional methods for preparing metallized grid lines usually include steps such as photolithography, screen printing and electroplating. Among these steps, electroplating technology has attracted widespread attention due to its low cost, high precision and little impact on cell performance.

[0003] However, in the electroplating process, a mask is usually needed to define the position of the metallized gate line. The traditional photolithography mask process is complex and costly, so finding a simple and effective mask material has become an important research direction. Summary of the invention

[0004] The object of the present invention is to provide a process using a strippable blue glue as an electroplating seed layer to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a process using a strippable blue glue as an electroplating seed layer, comprising the following steps:

[0006] Step 1, seed layer preparation: a layer of peelable blue glue is evenly coated on the surface of the HJT cell and cured by ultraviolet light. The coating thickness of the blue glue is 5-50 microns;

[0007] Step 2, copper electroplating process: Place the HJT battery coated with blue glue in the copper electroplating solution. During the electroplating process, copper ions are deposited on the battery surface outside the blue glue protection area to form metallized grid lines. The electroplating parameters include current density, time and temperature. The electroplating parameters are optimized according to the characteristics of the HJT battery to ensure the thickness and uniformity of the copper grid lines.

[0008] Step 3, blue glue stripping: After the electroplating is completed, the blue glue is stripped by physical methods. The stripped blue glue will not leave residue on the surface of the battery, ensuring that the photoelectric conversion efficiency of the HJT battery is not affected, and the stripped blue glue is used for recycling;

[0009] Step 4, post-processing: After the blue glue is peeled off, the battery surface is cleaned and dried to ensure the stability and conductivity of the copper grid line. Finally, performance testing is carried out, specifically electrical testing and reliability testing, to ensure that the quality of the copper grid line meets the requirements.

[0010] Preferably, when the blue glue is coated on the surface of the HJT battery in step 1, the silk screen printing edge is ensured to be smooth, the hole covering force is strong and the flow is very long, wherein the strippable blue glue is solvent-free, volatile, environmentally friendly and safe, does not contain any metal and non-metal monomers, and will not dissolve any substance during the anti-corrosion process.

[0011] Preferably, the current density in the electroplating parameters in step 2 is monitored by an electrochemical sensor to monitor the concentration change of copper ions in the electroplating solution, wherein the electrochemical sensor feeds back the content of copper ions in the electroplating solution in real time, and the deposition rate of copper ions is obtained according to the detection data to adjust the electroplating parameters; the temperature in the electroplating parameters is monitored by installing a temperature sensor in the electroplating equipment to monitor the temperature of the electroplating solution, and the temperature data fed back by the temperature sensor is used to timely adjust the heating or cooling device to keep the temperature of the electroplating solution within an appropriate range.

[0012] Preferably, the specific steps of peeling off the blue glue by physical method in step 3 are as follows:

[0013] Step 31, equipment selection: select appropriate mechanical stripping equipment, specifically use an automatic stripping machine with fine operation function;

[0014] Step 32, environmental control: ensure the cleanliness and stability of the peeling environment, and keep the ambient temperature and humidity within a suitable range, specifically, the temperature is controlled at 20°C-25°C, and the relative humidity is 40%-60%, to prevent the blue glue from changing abnormally due to environmental factors;

[0015] Step 33, battery appearance inspection: Before mechanical stripping, perform an appearance inspection on the battery after electroplating to observe the coverage of the blue glue on the battery surface, whether there is any local lifting, falling off or separation from the battery surface, and check whether there are any obvious defects or damages on the battery surface;

[0016] Step 34, blue glue status assessment: by gently touching the surface of the blue glue, feel its hardness and stickiness, preliminarily judge the ease of peeling, and assess the curing degree and hardness of the blue glue;

[0017] Step 35, fix the battery: fix the battery with blue glue to be peeled on the workbench of the peeling equipment to ensure that the battery is in a stable position and will not move during the peeling process;

[0018] Step 36, setting peeling parameters: using an automatic peeling machine, set the appropriate peeling force and angle according to the thickness and hardness of the blue glue and the size and material of the battery. The peeling angle is usually between 30° and 60°. This peeling angle range allows the peeling force to better act on the separation interface between the blue glue and the battery surface.

[0019] Step 37, start stripping: start the stripping device or start the manual stripping operation. During the stripping process, check in real time through the camera or observation window on the device. If you find that there is any blue glue residue or the battery surface shows signs of damage, stop the stripping operation immediately, adjust the stripping parameters and start again;

[0020] Step 38, inspection after stripping: After stripping, carefully inspect the battery surface to see if there is any blue glue residue. Use a magnifying glass or microscope to assist in the inspection to ensure that the battery surface is clean and free of any blue glue residue. If any residue is found, use a local cleaning method and use a clean cotton swab dipped in a small amount of organic solvent to gently wipe the remaining area.

[0021] Preferably, the electrical test and reliability test in step 4 specifically include the following contents:

[0022] Electrical test: Evaluate the conductivity of the copper grid and its electrical connection with other parts of the battery. Through electrical testing, determine whether the copper grid meets the conductivity requirements of the design and whether there are electrical defects. Specifically, use a four-probe tester to measure the resistivity of the copper grid. The design requires that the resistivity of the copper grid is not higher than a certain value. The resistivity value obtained by measurement is compared with the design requirement. When the measured value is higher than the design requirement, the copper grid has defects. At the same time, an oscilloscope is used to observe the electrical connection between the copper grid and other parts of the battery.

[0023] Reliability test: Evaluate the stability and reliability of the copper grid under different environmental conditions and usage scenarios. Through reliability testing, predict whether the copper grid will experience performance degradation or failure during long-term use, thereby ensuring the quality and service life of the battery; Specifically:

[0024] a. Temperature cycle test: Place the HJT battery in an environmental test chamber, set the temperature cycle range from -40℃ to 80℃, perform multiple cycles within this temperature range, and observe the performance changes of the copper grid during the temperature change process, including whether the resistivity of the copper grid changes significantly with the temperature change, and whether there is a poor electrical connection caused by temperature change. Through the temperature cycle test, the adaptability and stability of the copper grid in different temperature environments are evaluated;

[0025] b. Humidity cycle test: Use an environmental test chamber and set the humidity cycle range to 10% to 90% relative humidity. During the humidity cycle, observe the performance changes of the copper grid. High humidity environment will cause oxidation or corrosion of the copper grid, and low humidity environment will affect the electrical performance of the copper grid. Through humidity cycle test, evaluate the adaptability and stability of the copper grid in different humidity environments;

[0026] c. Long-term stability test: The long-term stability of the copper grid line is tested through an accelerated life test model. According to the actual use and design requirements of the HJT battery, the performance changes of the copper grid line in a certain period of time in the future are predicted.

[0027] Compared with the prior art, the beneficial effects of the present invention are: compared with the traditional silver electrode process, the use of copper electroplating in the present invention greatly reduces the material cost, and the use of strippable blue glue as a seed layer reduces the process steps and time, further reducing the overall production cost; the good adhesion and electroplating performance of the blue glue enable the copper grid lines to be formed quickly, shortening the manufacturing cycle of the battery; the blue glue after electroplating can be easily peeled off and will not leave residue on the surface of the HJT battery, ensuring the final performance of the battery; the recyclability of the strippable blue glue makes the process more environmentally friendly and conducive to sustainable production. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the process flow of the present invention. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0030] See also Figure 1 The present invention provides a technical solution: a process using a strippable blue glue as an electroplating seed layer, comprising the following steps:

[0031] Step 1: Seed layer preparation: a layer of peelable blue glue is evenly coated on the surface of the HJT cell and cured by ultraviolet light. The thickness of the blue glue coating is 5-50 microns.

[0032] Step 2, copper electroplating process: Place the HJT battery coated with blue glue in the copper electroplating solution. During the electroplating process, copper ions are deposited on the battery surface outside the blue glue protection area to form metallized grid lines. The electroplating parameters include current density, time and temperature. The electroplating parameters are optimized according to the characteristics of the HJT battery to ensure the thickness and uniformity of the copper grid lines.

[0033] Step 3, blue glue stripping: After the electroplating is completed, the blue glue is stripped by physical methods. The stripped blue glue will not leave residue on the surface of the battery, ensuring that the photoelectric conversion efficiency of the HJT battery is not affected, and the stripped blue glue is used for recycling;

[0034] Step 4, post-processing: After the blue glue is peeled off, the battery surface is cleaned and dried to ensure the stability and conductivity of the copper grid line. Finally, performance testing is carried out, specifically electrical testing and reliability testing, to ensure that the quality of the copper grid line meets the requirements.

[0035] Furthermore, in step 1, when the blue glue is coated on the surface of the HJT battery, the silk screen printing edge is ensured to be smooth, the hole covering force is strong and the flow is very long. The strippable blue glue is solvent-free, environmentally friendly and safe, and does not contain any metal or non-metal monomers. No substance will be dissolved during the anti-corrosion process.

[0036] Furthermore, in step 2, the current density in the electroplating parameters is monitored by an electrochemical sensor to monitor the concentration change of copper ions in the electroplating solution, wherein the electrochemical sensor feeds back the content of copper ions in the electroplating solution in real time, obtains the deposition rate of copper ions according to the detection data, and adjusts the electroplating parameters; the temperature in the electroplating parameters is monitored by installing a temperature sensor in the electroplating equipment to monitor the temperature of the electroplating solution, and the temperature data fed back by the temperature sensor is used to timely adjust the heating or cooling device to keep the temperature of the electroplating solution within an appropriate range.

[0037] Furthermore, the specific steps of removing the blue glue by physical method in step 3 are as follows:

[0038] Step 31, equipment selection: select appropriate mechanical stripping equipment, specifically use an automatic stripping machine with fine operation function;

[0039] Step 32, environmental control: ensure the cleanliness and stability of the peeling environment, and keep the ambient temperature and humidity within a suitable range, specifically, the temperature is controlled at 20°C-25°C, and the relative humidity is 40%-60%, to prevent the blue glue from changing abnormally due to environmental factors;

[0040] Step 33, battery appearance inspection: Before mechanical stripping, perform an appearance inspection on the battery after electroplating to observe the coverage of the blue glue on the battery surface, whether there is any local lifting, falling off or separation from the battery surface, and check whether there are any obvious defects or damages on the battery surface;

[0041] Step 34, blue glue status assessment: by gently touching the surface of the blue glue, feel its hardness and stickiness, preliminarily judge the ease of peeling, and assess the curing degree and hardness of the blue glue;

[0042] Step 35, fix the battery: fix the battery with blue glue to be peeled on the workbench of the peeling equipment to ensure that the battery is in a stable position and will not move during the peeling process;

[0043] Step 36, setting peeling parameters: using an automatic peeling machine, set the appropriate peeling force and angle according to the thickness and hardness of the blue glue and the size and material of the battery. The peeling angle is usually between 30° and 60°. This peeling angle range allows the peeling force to better act on the separation interface between the blue glue and the battery surface.

[0044] Step 37, start stripping: start the stripping device or start the manual stripping operation. During the stripping process, check in real time through the camera or observation window on the device. If you find that there is any blue glue residue or the battery surface shows signs of damage, stop the stripping operation immediately, adjust the stripping parameters and start again;

[0045] Step 38, inspection after stripping: After stripping, carefully inspect the battery surface to see if there is any blue glue residue. Use a magnifying glass or microscope to assist in the inspection to ensure that the battery surface is clean and free of any blue glue residue. If any residue is found, use a local cleaning method and use a clean cotton swab dipped in a small amount of organic solvent to gently wipe the remaining area.

[0046] Furthermore, the electrical test and reliability test in step 4 specifically include the following contents:

[0047] Electrical test: Evaluate the conductivity of the copper grid and its electrical connection with other parts of the battery. Through electrical testing, determine whether the copper grid meets the conductivity requirements of the design and whether there are electrical defects. Specifically, use a four-probe tester to measure the resistivity of the copper grid. The design requires that the resistivity of the copper grid is not higher than a certain value. The resistivity value obtained by measurement is compared with the design requirement. When the measured value is higher than the design requirement, the copper grid has defects. At the same time, an oscilloscope is used to observe the electrical connection between the copper grid and other parts of the battery.

[0048] Reliability test: Evaluate the stability and reliability of the copper grid under different environmental conditions and usage scenarios. Through reliability testing, predict whether the copper grid will experience performance degradation or failure during long-term use, thereby ensuring the quality and service life of the battery; Specifically:

[0049] a. Temperature cycle test: Place the HJT battery in an environmental test chamber, set the temperature cycle range from -40℃ to 80℃, perform multiple cycles within this temperature range, and observe the performance changes of the copper grid during the temperature change process, including whether the resistivity of the copper grid changes significantly with the temperature change, and whether there is a poor electrical connection caused by temperature change. Through the temperature cycle test, the adaptability and stability of the copper grid in different temperature environments are evaluated;

[0050] b. Humidity cycle test: Use an environmental test chamber and set the humidity cycle range to 10% to 90% relative humidity. During the humidity cycle, observe the performance changes of the copper grid. High humidity environment will cause oxidation or corrosion of the copper grid, and low humidity environment will affect the electrical performance of the copper grid. Through humidity cycle test, evaluate the adaptability and stability of the copper grid in different humidity environments;

[0051] c. Long-term stability test: The long-term stability of the copper grid line is tested through an accelerated life test model. According to the actual use and design requirements of the HJT battery, the performance changes of the copper grid line in a certain period of time in the future are predicted.

[0052] Compared with the traditional silver electrode process, the present invention uses copper electroplating to reduce material costs, and the strippable blue glue as a seed layer reduces process steps and time, further reducing the overall production cost. The recyclability of the blue glue also helps to continuously reduce costs; the good adhesion and electroplating performance of the blue glue enable the copper grid lines to be formed quickly, significantly shortening the battery manufacturing cycle; the electroplated blue glue is easy to peel off and has no residue, ensuring the final performance of the battery. Strict post-processing and performance testing measures ensure the high quality of the copper grid lines and meet electrical and reliability requirements; the recyclability of the strippable blue glue makes the process more environmentally friendly, in line with the concept of sustainable production, and reduces the impact on the environment; the process provided by the present invention has broad application prospects in the field of photovoltaic cell manufacturing, and is expected to promote the development of HJT battery manufacturing technology, improve the production efficiency and quality of photovoltaic cells, while reducing production costs and environmental impacts, and contributing to the development of the renewable energy industry.

[0053] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process using a strippable blue glue as an electroplating seed layer, characterized in that: The following steps are involved: Step 1, seed layer preparation: a layer of peelable blue glue is evenly coated on the surface of the HJT cell and cured by ultraviolet light. The coating thickness of the blue glue is 5-50 microns; Step 2, copper electroplating process: Place the HJT battery coated with blue glue in the copper electroplating solution. During the electroplating process, copper ions are deposited on the battery surface outside the blue glue protection area to form metallized grid lines. The electroplating parameters include current density, time and temperature. The electroplating parameters are optimized according to the characteristics of the HJT battery to ensure the thickness and uniformity of the copper grid lines. Step 3, blue glue stripping: After the electroplating is completed, the blue glue is stripped by physical methods. The stripped blue glue will not leave residue on the surface of the battery, ensuring that the photoelectric conversion efficiency of the HJT battery is not affected, and the stripped blue glue is used for recycling; Step 4, post-processing: After the blue glue is peeled off, the battery surface is cleaned and dried to ensure the stability and conductivity of the copper grid line. Finally, performance testing is carried out, specifically electrical testing and reliability testing, to ensure that the quality of the copper grid line meets the requirements.

2. The process of using a strippable blue glue as an electroplating seed layer according to claim 1, characterized in that: In the step 1, when the blue glue is coated on the surface of the HJT battery, the silk screen printing edge is ensured to be smooth, the hole covering force is strong and the flow is very long. The strippable blue glue is solvent-free, environmentally friendly and safe, does not contain any metal or non-metal monomers, and will not dissolve any substance during the anti-corrosion process.

3. The process of using a strippable blue glue as an electroplating seed layer according to claim 1, characterized in that: In the step 2, the current density in the electroplating parameters is monitored by an electrochemical sensor to monitor the concentration change of copper ions in the electroplating solution, wherein the electrochemical sensor feeds back the content of copper ions in the electroplating solution in real time, and the deposition rate of copper ions is obtained according to the detection data to adjust the electroplating parameters; the temperature in the electroplating parameters is monitored by installing a temperature sensor in the electroplating equipment to monitor the temperature of the electroplating solution, and the temperature data fed back by the temperature sensor is used to timely adjust the heating or cooling device to keep the temperature of the electroplating solution within an appropriate range.

4. The process of using a strippable blue glue as an electroplating seed layer according to claim 1, characterized in that: The specific steps of peeling off the blue glue by physical method in step 3 are as follows: Step 31, equipment selection: select appropriate mechanical stripping equipment, specifically use an automatic stripping machine with fine operation function; Step 32, environmental control: ensure the cleanliness and stability of the peeling environment, and keep the ambient temperature and humidity within a suitable range, specifically, the temperature is controlled at 20°C-25°C, and the relative humidity is 40%-60%, to prevent the blue glue from changing abnormally due to environmental factors; Step 33, battery appearance inspection: Before mechanical stripping, perform an appearance inspection on the battery after electroplating to observe the coverage of the blue glue on the battery surface, whether there is any local lifting, falling off or separation from the battery surface, and check whether there are any obvious defects or damages on the battery surface; Step 34, blue glue status assessment: by gently touching the surface of the blue glue, feel its hardness and stickiness, preliminarily judge the ease of peeling, and assess the curing degree and hardness of the blue glue; Step 35, fix the battery: fix the battery with blue glue to be peeled on the workbench of the peeling equipment to ensure that the battery is in a stable position and will not move during the peeling process; Step 36, setting peeling parameters: using an automatic peeling machine, set the appropriate peeling force and angle according to the thickness and hardness of the blue glue and the size and material of the battery. The peeling angle is usually between 30° and 60°. This peeling angle range allows the peeling force to better act on the separation interface between the blue glue and the battery surface. Step 37, start stripping: start the stripping device or start the manual stripping operation. During the stripping process, check in real time through the camera or observation window on the device. If you find that there is any blue glue residue or the battery surface shows signs of damage, stop the stripping operation immediately, adjust the stripping parameters and start again; Step 38, inspection after stripping: After stripping, carefully inspect the battery surface to see if there is any blue glue residue. Use a magnifying glass or microscope to assist in the inspection to ensure that the battery surface is clean and free of any blue glue residue. If any residue is found, use a local cleaning method and use a clean cotton swab dipped in a small amount of organic solvent to gently wipe the remaining area.

5. The process of using a strippable blue glue as an electroplating seed layer according to claim 1, characterized in that: The electrical test and reliability test in step 4 specifically include the following contents: Electrical test: Evaluate the conductivity of the copper grid and its electrical connection with other parts of the battery. Through electrical testing, determine whether the copper grid meets the conductivity requirements of the design and whether there are electrical defects. Specifically, use a four-probe tester to measure the resistivity of the copper grid. The design requires that the resistivity of the copper grid is not higher than a certain value. The resistivity value obtained by measurement is compared with the design requirement. When the measured value is higher than the design requirement, the copper grid has defects. At the same time, an oscilloscope is used to observe the electrical connection between the copper grid and other parts of the battery. Reliability test: Evaluate the stability and reliability of the copper grid under different environmental conditions and usage scenarios. Through reliability testing, predict whether the copper grid will experience performance degradation or failure during long-term use, thereby ensuring the quality and service life of the battery; Specifically: a. Temperature cycle test: Place the HJT battery in an environmental test chamber, set the temperature cycle range from -40℃ to 80℃, perform multiple cycles within this temperature range, and observe the performance changes of the copper grid during the temperature change process, including whether the resistivity of the copper grid changes significantly with the temperature change, and whether there is a poor electrical connection caused by temperature change. Through the temperature cycle test, the adaptability and stability of the copper grid in different temperature environments are evaluated; b. Humidity cycle test: Use an environmental test chamber and set the humidity cycle range to 10% to 90% relative humidity. During the humidity cycle, observe the performance changes of the copper grid. High humidity environment will cause oxidation or corrosion of the copper grid, and low humidity environment will affect the electrical performance of the copper grid. Through humidity cycle test, evaluate the adaptability and stability of the copper grid in different humidity environments; c. Long-term stability test: The long-term stability of the copper grid line is tested through an accelerated life test model. According to the actual use and design requirements of the HJT battery, the performance changes of the copper grid line in a certain period of time in the future are predicted.

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