Anti-aging silver-coated copper conductive powder and preparation method thereof
By optimizing raw materials and processes, silver-clad copper conductive powder with anti-aging properties is prepared, which solves the problems of expensive and unstable quality of silver-clad copper powder in the prior art, and achieves good aging performance of HJT solar cells in high temperature and high humidity environments.
Patent Information
- Application Number
- CN202510257706.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-05
- Publication Date
- 2025-05-30
AI Technical Summary
In the prior art, the price of the bank-clad copper powder is expensive and the quality is unstable, resulting in poor electrical performance and poor aging performance of HJT solar cells.
By optimizing key raw materials and process processes, a silver-clad copper conductive powder with anti-aging properties was prepared. The particle size distribution and tap density were improved, and it showed good aging performance in high temperature and high humidity environments.
The batch consistency and electrical performance stability of silver-clad copper conductive powder are achieved, and the aging performance requirements of HJT solar cells in high temperature and high humidity environments are met.
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Figure CN120055261A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of the production of metal powders, and particularly relates to a silver-coated copper conductive powder with anti-aging performance and a preparation method thereof. Background Art
[0002] With the development of solar power generation battery technology, heterojunction (HJT) batteries, which adopt a low-temperature manufacturing process and have a high photoelectric conversion rate, have received extensive favor in the market. HJT batteries are a new type of photovoltaic battery technology with advantages such as high efficiency, low attenuation, and good stability. In HJT batteries, silver-coated copper powder, as a substitute material for silver powder, can further improve the conductivity and stability of the battery and reduce the manufacturing cost.
[0003] However, heterojunction batteries made of silver-coated copper powder HJT solar pastes have the following problems: First, the silver-coated copper powder used by most low-temperature curing HJT solar cell paste manufacturers in the industry is expensive; Second, the performance fluctuations between batches of silver-coated copper powder produced by different manufacturers are large. Especially when the silver-coated copper powder is made into a paste and subjected to an anti-aging test, the performance cannot meet the requirements of the production line. Summary of the Invention
[0004] Aiming at the problems in the prior art that the silver-coated copper powder is expensive, the compactness and consistency of the surface of the copper powder coated with a silver layer are unstable, and the electrical performance of the made HJT battery is poor, and the performance drops significantly during the electrical performance aging test, the present invention provides a silver-coated copper conductive powder with anti-aging performance and a preparation method thereof. Careful optimization has been carried out on the key raw materials and manufacturing processes. The produced silver-coated copper powder (silver-coated copper conductive powder) has stable batch consistency. When it is applied to a temperature-curing HJT solar cell paste, it has excellent photoelectric conversion efficiency. Finally, the made heterojunction solar cell has good effects in the high-temperature and high-humidity test (double 85 experiment) after being encapsulated into a module, meeting the requirements of the production line.
[0005] The object of the present invention is achieved by the following technical solutions: A preparation method of a silver-coated copper conductive powder with anti-aging performance, comprising the following steps: S1. Mix copper powder and an anhydrous ethanol solvent with a volume concentration of 99% according to a mass ratio of 1:(1 - 2), then add an alkanolamine compound solution with a volume concentration of 99%. The addition amount of the alkanolamine compound solution is 0.2% - 0.5% of the mass of the copper powder. Stir while heating to 35°C - 40°C, and then stir for 10 min; Then, ultrasonic cleaning is carried out for 3 min - 5 min to separate the copper powder from the solution, and then the same proportion of anhydrous ethanol with a volume concentration of 99% is added and stirred; after repeating the operations of ultrasonic cleaning and copper powder separation three times, the coating agent and impurities on the surface of the copper powder are cleaned, and finally separated from the anhydrous ethanol; The copper powder is a round solid single - particle dispersed high - crystalline powder, and its particle size distribution is D 10 is 2.0 - 3.0, D 50 is 3.0 - 4.0, D 90 is 6.0 - 8.5, and the tapped density is 5.5 - 6.5; The alkanolamine compound is selected from triethanolamine or diethanolamine, or any proportion mixture of the two; S2. Deionized water is added to the copper powder obtained in the previous step. The copper powder and deionized water are mixed at a mass ratio of 1:(5 - 10), and while stirring, the overall solution temperature is controlled at 35°C - 40°C. Subsequently, a modified polyether dispersant is added, and the addition amount of the modified polyether dispersant is 0.3% - 2% of the mass of the copper powder; the modified polyether dispersant is selected from polyether modified by hydroxyacrylic acid; A water - soluble porphyrin compound is added, and the addition amount of the water - soluble porphyrin compound is 0.1% - 0.8% of the mass of the copper powder; After adding the water - soluble porphyrin compound and stirring for 5 min, a stannous chloride solution is added to the solution. The addition amount of stannous chloride is 0.03% - 0.1% of the mass of the copper powder, and stirred for 10 min; the water - soluble porphyrin compound is selected from aminotetraphenylporphyrin (TAPP), or derivatives with a similar structure to TAPP, or any proportion mixture of the two; A thiophene compound is added, and the addition amount of the thiophene compound is 0.1% - 0.5% of the mass of the copper powder; the thiophene compound is selected from 2 - thiopheneacetic acid or thiophene chemical derivatives with a similar structure; An organic acid compound is added, and the addition amount of the organic acid compound is 1% - 3% of the mass of the copper powder. The organic acid compound is selected from one or several of citric acid, oxalic acid, succinic acid, tartaric acid in any proportion mixture; Finally, a 99% volume - concentration alkanolamine compound solution is added. The addition amount of the alkanolamine compound solution is 2% - 5% of the mass of the copper powder, and while stirring, it is kept at a constant temperature of 35°C - 40°C and stirred for 10 min; S3. Silver nitrate is dissolved in deionized water. The mass ratio of silver nitrate to deionized water is 1:(5 - 10), and the mass ratio of silver nitrate to copper powder is 1:(1.0 - 3.5). While stirring, it is heated to 35°C - 40°C; S4. Slowly add the solution in S3 to the solution in S2, controlling the whole process within 15 - 20 minutes and the temperature at 35°C - 40°C to obtain silver-coated copper powder; S5. Filter the silver-coated copper powder and wash it 3 times with deionized water, with the conductivity ≤ 30. Obtain wet silver-coated copper powder; S6. Dissolve the coating agent in absolute ethanol. The addition amount of the coating agent is 0.03% - 0.1% of the mass of the copper powder, and the addition amount of alcohol is 3 - 20 times the mass of the coating agent; then add it to the wet silver-coated copper powder and stir, then separate; The coating agent is selected from one of oleic acid, stearic acid, lauric acid, or any mixture in any proportion; S7. Dry the wet silver-coated copper powder separated in the above step at a temperature of 60°C for 12 hours to obtain a silver-coated copper conductive powder with anti-aging performance (highly vibration-compacted single-particle dispersed silver-coated copper powder). The particle size distribution of this silver-coated copper conductive powder is D 10 is 2.0 - 3.3, D 50 is 3.5 - 5.5, D 90 is 6.0 - 9.0, the tap density is 4.5 - 6.5, and the silver content is 20% - 35%. For the HJT paste prepared using this silver-coated copper conductive powder with anti-aging performance, Voc (open voltage) is 740.3 mV - 740.8 mV, Jsc (current) is 38.69 mA / cm 2 - 39.56 mA / cm 2 , FF (fill factor) is 82.66% - 82.87%, Eta (efficiency) is 23.82% - 23.87%, the efficiency before the aging experiment is 23.82% - 23.87%, and the efficiency after the aging experiment is 23.77% - 23.81%.
[0006] In the present invention: Further, the copper powder described in S1 is round solid single-particle dispersed high-crystalline powder, and its particle size distribution is D 10 is 2.0 - 3.0, D 50 is 3.5, D 90 is 6.0 - 8.5, the tap density is 5.5 - 6.5, and the silver content is 20% - 35%.
[0007] The modified polyether dispersant described in S2 is hydroxyl acrylic acid modified polyether. The function of this kind of dispersant is to keep the generated copper powder particles in a single-particle dispersed state in the deionized water solution and not cause hard agglomeration during the subsequent silver layer coating reaction process.
[0008] The function of adding stannous chloride solution, water-soluble porphyrin compounds and thiophene compounds in S2 is that when silver is plated on the surface of copper powder, it can affect the bonding strength between the copper layer and the silver layer, as well as the wrapping bonding rate of silver plating on the surface of copper powder. Specifically, after adding such substances, the aging performance of the silver-coated copper paste in a high-temperature and high-humidity environment will be significantly improved.
[0009] The present invention also relates to a silver-coated copper conductive powder with anti-aging performance, which is obtained according to the preparation method of the above silver-coated copper conductive powder with anti-aging performance. The particle size distribution of the silver-coated copper conductive powder is D 10 of 2.0 - 3.3, D 50 of 3.5 - 5.5, D 90 of 6.0 - 9.0, the tapped density is 4.5 - 6.5, the silver content therein is 20% - 35%. For the HJT paste prepared using the silver-coated copper conductive powder with anti-aging performance, Voc (open voltage) is 740.3 mV - 740.8 mV, Jsc (current) is 38.69 mA / cm 2 - 39.56 mA / cm 2 , FF (fill factor) is 82.66% - 82.87%, Eta (efficiency) is 23.82% - 23.87%, the efficiency before the aging experiment is 23.82% - 23.87%, and the efficiency after the aging experiment is 23.77% - 23.81%.
[0010] Compared with the prior art, the present invention has the following beneficial effects: 1. The preparation method of the silver-coated copper conductive powder with anti-aging performance according to the present invention has good batch stability of the prepared silver-coated copper conductive powder with anti-aging performance, and can meet the technical requirements and production design of silver-coated copper conductive powders with different silver contents.
[0011] 2. Currently, in the replacement of pure silver powder paste for HJT conductive powder, a silver-coated copper conductive powder designed with a silver content of 30% can be used for replacement, which meets the requirements in the production line test. The HJT paste prepared using the silver-coated copper conductive powder with anti-aging performance according to the present invention has the same data as the silver-coated copper conductive powder designed with a silver content of 30% used in the existing production line in the production line electrical performance test and subsequent aging test. Moreover, through the comparison of comparative experiments, the silver-coated copper conductive powder with anti-aging performance prepared by the present invention has obvious advantages in the electrical performance attenuation after aging, and the bonding force between the silver layer and the copper layer of the silver-coated copper conductive powder prepared by the present invention has obvious advantages. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The drawings are used to provide further understanding of the present invention, and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention.
[0013] Figure 1 SEM image of the silver-coated copper conductive powder with anti-aging performance prepared in Example 1 of the present invention. Detailed implementation manner
[0014] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.
[0015] Example 1: A preparation method of silver-coated copper conductive powder with anti-aging performance, comprising the following steps: Add 1 kg of round solid single-particle dispersed highly crystalline copper powder with a particle size distribution of D 10 being 2.3, D 50 being 3.5, D 90 being 7.2 and a tapped density of 6.5; add the copper powder to 1 kg of anhydrous ethanol solvent with a volume concentration of 99%, then add 3 g of triethanolamine solution with a volume concentration of 99%, heat to 35°C - 40°C while stirring, stir for another 10 min, then perform ultrasonic cleaning for 3 - 5 min, then separate the copper powder and anhydrous ethanol, and continue to add 1 kg of anhydrous ethanol with a volume concentration of 99% for mixing and stirring; after repeating this operation three times, clean the coating agent and other impurities on the surface of the copper powder, and finally separate it from the anhydrous ethanol; Add 5 liters of deionized water to the copper powder, start stirring, and control the overall solution temperature at 35°C - 40°C while stirring; subsequently, add 5 g of modified polyether dispersant, add 1.2 g of tetracarboxyphenyl porphyrin (TCPP), stir for 5 min, then add 0.5 g of tin chloride solution to the solution, stir for 10 min, then add 3 g of thiophene-3-carboxylic acid, then add 12 g of tartaric acid, and finally add 23 g of triethanolamine solution with a volume concentration of 99%, heat to 35°C - 40°C while stirring, and stir for 10 min; Dissolve 472 g of silver nitrate in 4 liters of deionized water, heat to 35°C - 40°C while stirring; Slowly add the silver nitrate solution to the copper powder solution, control the whole process within 15 min, and control the temperature at 35°C - 40°C; Then silver-coated copper powder is obtained; filter out the silver-coated copper powder and wash it with deionized water 3 times, and the conductivity reaches below 30; Dissolve 0.3 g of coating agent oleic acid in 5 g of alcohol with a volume concentration of 99%, and then add it to the wet silver-coated copper powder for stirring; The wet silver-coated copper powder obtained from the above separation step is dried at 60 °C for 12 h to finally obtain silver-coated copper conductive powder with anti-aging performance (silver-coated copper powder with high tap density and single-particle dispersion). As Figure 1 shown is the SEM image of the silver-coated copper conductive powder with anti-aging performance prepared in Example 1. The particle size distribution of this silver-coated copper conductive powder is D 10 of 2.6, D 50 of 4.3, D 90 of 7.9, the tap density is 5.9, and the silver content tested is 30%.
[0016] Example 2: Preparation of silver-coated copper conductive powder with anti-aging performance, including the following steps: 1 kg of round solid single-particle dispersed high-crystallinity copper powder with a particle size distribution of D 10 of 3.0, D 50 of 4.0, D 90 of 8.3, and the tap density of 6.0; this copper powder is added to 1.5 kg of anhydrous ethanol solvent with a volume concentration of 99%, then 5 g of diethanolamine solution with a volume concentration of 99% is added, and it is heated to 35 °C - 40 °C while stirring, then stirred for 10 min, then ultrasonically cleaned for 3 - 5 min, then the copper powder and anhydrous ethanol are separated, and then 1.5 kg of anhydrous ethanol with a volume concentration of 99% is added and stirred; after repeating this operation three times, the coating agent and other impurities on the surface of the copper powder are cleaned, and finally separated from the anhydrous ethanol; 10 L of deionized water is added to the copper powder, stirring is started, and the overall solution temperature is controlled at 35 °C - 40 °C while stirring; subsequently, 20 g of modified polyether dispersant is added, after adding 8.0 g of tetracarboxyphenyl porphyrin (TCPP) and stirring for 5 min, then 1.0 g of tin chloride solution is added to the solution, after stirring for 10 min, 5 g of thiophene-3-carboxylic acid is added, then 30 g of citric acid is added, and finally 50 g of diethanolamine solution with a volume concentration of 99% is added, and it is kept at a constant temperature of 35 °C - 40 °C while stirring, and stirred for 10 min; 315 g of silver nitrate is dissolved in 3 L of deionized water and heated to 35 °C - 40 °C while stirring; The silver nitrate solution is slowly added to the copper powder solution, and the whole process is controlled within 15 min, and the temperature is controlled at 35 °C - 40 °C; Then silver-coated copper powder is obtained; the silver-coated copper powder is filtered out and washed 3 times with deionized water, and the conductivity reaches below 30; 0.3 g of coating agent oleic acid and 0.3 g of coating agent lauric acid are dissolved in 5 g of alcohol with a volume concentration of 99%, and then added to the wet silver-coated copper powder and stirred; The wet silver-coated copper powder obtained by the above separation step is dried at 60 °C for 12 h, and finally silver-coated copper conductive powder with anti-aging performance (silver-coated copper powder with high tap density and single-particle dispersion) is obtained. The particle size distribution of the silver-coated copper conductive powder is D 10 is 3.2, D 50 is 5.3, D 90 is 8.6, the tap density is 5.5, and the measured silver content is 20%.
[0017] Example 3: Preparation of silver-coated copper conductive powder with anti-aging performance, including the following steps: 1 kg of round solid single-particle dispersed high-crystalline copper powder with a particle size distribution of D 10 is 2.3, D 50 is 3.5, D 90 is 7.2, and the tap density is 6.5; this copper powder is added to 1.5 kg of anhydrous ethanol solvent with a volume concentration of 99%, and then 5 g of diethanolamine solution with a volume concentration of 99% is added. While stirring, it is heated to 35 °C - 40 °C, and then stirred for 10 min, then ultrasonically cleaned for 3 - 5 min, and then the copper powder and anhydrous ethanol are separated, and then 1.5 kg of anhydrous ethanol with a volume concentration of 99% is added and stirred; after repeating this operation three times, the coating agent and other impurities on the surface of the copper powder are cleaned, and finally separated from the anhydrous ethanol; 10 L of deionized water is added to the copper powder, and stirring is started. While stirring, the overall solution temperature is controlled at 35 °C - 40 °C; subsequently, 20 g of modified polyether dispersant is added, after adding 8.0 g of tetracarboxyphenyl porphyrin (TCPP) and stirring for 5 min, then 1.0 g of tin chloride solution is added to the solution, after stirring for 10 min, 5 g of thiophene-3-carboxylic acid is added, then 30 g of tartaric acid is added, and finally 50 g of diethanolamine solution with a volume concentration of 99% is added. While stirring, it is heated to 35 °C - 40 °C and stirred for 10 min; 551 g of silver nitrate is dissolved in 5 L of deionized water, and while stirring, it is heated to 35 °C - 40 °C; The silver nitrate solution is slowly added to the copper powder solution, and the whole process is controlled within 15 min, and the temperature is controlled at 35 °C - 40 °C; Then silver-coated copper powder is obtained; the silver-coated copper powder is filtered out and washed with deionized water 3 times, and the conductivity reaches below 30; 0.3 g of coating agent lauric acid is dissolved in 3 g of alcohol with a volume concentration of 99%, and then added to the wet silver-coated copper powder and stirred; The wet silver-coated copper powder obtained by the above separation steps is dried at 60 °C for 12 h, and finally silver-coated copper conductive powder with anti-aging performance (silver-coated copper powder with high tap density and single-particle dispersion) is obtained. The particle size distribution of the silver-coated copper conductive powder is D 10 is 2.9, D 50 is 4.8, D 90 is 8.3, the tap density is 5.7, and the measured silver content is 35%.
[0018] Comparative Example 1: Compared with Example 1, the addition amount of silver nitrate is reduced to 160 g, and the others remain unchanged.
[0019] It includes the following steps: 1 kg of round solid single-particle dispersed high-crystallinity copper powder, the particle size distribution of which is D 10 is 2.3, D 50 is 3.5, D 90 is 7.2, and the tap density is 6.5; this copper powder is added to 1 kg of anhydrous ethanol solvent with a volume concentration of 99%, then 3 g of triethanolamine solution with a volume concentration of 99% is added, and it is heated to 35 °C - 40 °C while stirring, and then stirred for 10 min, then ultrasonically cleaned for 3 - 5 min, then the copper powder and anhydrous ethanol are separated, and then 1 kg of anhydrous ethanol with a volume concentration of 99% is added and stirred; after repeating this operation three times, the coating agent and other impurities on the surface of the copper powder are cleaned, and finally separated from the anhydrous ethanol; 5 liters of deionized water is added to the copper powder, stirring is started, and the overall solution temperature is controlled at 35 °C - 40 °C while stirring; subsequently, 5 g of modified polyether dispersant is added, after adding 1.2 g of tetracarboxyphenyl porphyrin (TCPP) and stirring for 5 min, then 0.5 g of tin chloride solution is added to the solution, after stirring for 10 min, 3 g of thiophene-3-carboxylic acid is added, then 12 g of tartaric acid is added, and finally 23 g of triethanolamine solution with a volume concentration of 99% is added, and it is kept at a constant temperature of 35 °C - 40 °C while stirring, and stirred for 10 min; 160 g of silver nitrate is dissolved in 4 liters of deionized water, and it is heated to 35 °C - 40 °C while stirring; The silver nitrate solution is slowly added to the copper powder solution, and the whole process is controlled within 15 min, and the temperature is controlled at 35 °C - 40 °C; Then silver-coated copper powder is obtained; the silver-coated copper powder is filtered out and washed with deionized water 3 times, and the conductivity reaches below 30; 0.3 g of coating agent oleic acid is dissolved in 5 g of anhydrous ethanol with a volume concentration of 99%, and then added to the wet silver-coated copper powder and stirred; The wet silver-coated copper powder obtained by the above separation step is dried at 60°C for 12 hours to finally obtain silver-coated copper conductive powder with anti-aging performance (silver-coated copper powder with high tap density and single-particle dispersion). The particle size distribution of this silver-coated copper conductive powder is D 10 is 2.6, D 50 is 4.3, D 90 is 7.9, the tap density is 5.9, and the silver content tested is 10%.
[0020] Comparative Example 2: Compared with Example 1, the addition of the polyether dispersant was removed, and the others remained unchanged; It includes the following steps: 1 kg of round solid single-particle dispersed high-crystallinity copper powder, with a particle size distribution of D 10 being 2.3, D 50 being 3.5, D 90 being 7.2, and the tap density being 6.5; this copper powder is added to 1 kg of anhydrous ethanol solvent with a volume concentration of 99%, then 3 g of triethanolamine solution with a volume concentration of 99% is added, heated to 35°C - 40°C while stirring, stirred for 10 min, then ultrasonically cleaned for 3 - 5 min, then the copper powder and anhydrous ethanol are separated, and then 1 kg of anhydrous ethanol with a volume concentration of 99% is added and stirred; after repeating this operation three times, the coating agent and other impurities on the surface of the copper powder are all cleaned, and finally separated from the anhydrous ethanol; 5 liters of deionized water is added to the copper powder, stirring is started, and the overall solution temperature is controlled at 35°C - 40°C while stirring; after adding 1.2 g of tetracarboxyphenyl porphyrin (TCPP) and stirring for 5 min, 0.5 g of tin chloride solution is added to the solution, stirred for 10 min, then 3 g of thiophene-3-carboxylic acid is added, then 12 g of tartaric acid is added, and finally 23 g of triethanolamine solution with a volume concentration of 99% is added, and the temperature is kept at 35°C - 40°C while stirring, and stirred for 10 min; 472 g of silver nitrate is dissolved in 4 liters of deionized water, and heated to 35°C - 40°C while stirring; The silver nitrate solution is slowly added to the copper powder solution, and the whole process is controlled within 15 min, and the temperature is controlled at 35°C - 40°C; Then silver-coated copper powder is obtained; the silver-coated copper powder is filtered out and washed with deionized water 3 times, and the conductivity reaches below 30.
[0021] 0.3 g of the coating agent oleic acid is dissolved in 5 g of anhydrous ethanol with a volume concentration of 99%, and then added to the wet silver-coated copper powder and stirred; The wet silver-coated copper powder obtained from the above separation step is dried at 60°C for 12 hours to finally obtain silver-coated copper conductive powder with anti-aging performance (high tap density single-particle dispersed silver-coated copper powder). The particle size distribution of this silver-coated copper conductive powder is D 10 is 4.1, D 50 is 6.2, D 90 is 10.3, the tap density is 4.7, and the measured silver content is 30%.
[0022] Comparative Example 3: Compared with Example 1, the addition of porphyrin, tin chloride, thiophene, and organic acid was removed, and the others remained unchanged; It includes the following steps: 1 kg of round solid single-particle dispersed highly crystalline copper powder with a particle size distribution of D 10 being 2.3, D50 being 3.5, D 90 being 7.2, and the tap density being 6.5; this copper powder is added to 1 kg of anhydrous ethanol solvent with a volume concentration of 99%, then 3 g of triethanolamine solution with a volume concentration of 99% is added, heated to 35°C - 40°C while stirring, stirred for 10 min, then ultrasonically cleaned for 3 - 5 min, then the copper powder and anhydrous ethanol are separated, and then 1 kg of anhydrous ethanol with a volume concentration of 99% is added and stirred; after repeating this operation three times, the coating agent and other impurities on the surface of the copper powder are cleaned, and finally separated from the anhydrous ethanol; 5 liters of deionized water is added to the copper powder, stirring is started, and the overall solution temperature is controlled at 35°C - 40°C while stirring; subsequently, 5 g of modified polyether dispersant is added, and finally 23 g of triethanolamine solution with a volume concentration of 99% is added, and the temperature is kept constant at 35°C - 40°C while stirring, and stirred for 10 min; 472 g of silver nitrate is dissolved in 4 liters of deionized water, and heated to 35°C - 40°C while stirring; The silver nitrate solution is slowly added to the copper powder solution, and the whole process is controlled within 15 min, and the temperature is controlled at 35°C - 40°C; Then silver-coated copper powder is obtained; the silver-coated copper powder is filtered out and washed 3 times with deionized water, and the conductivity reaches below 30; 0.3 g of coating agent oleic acid is dissolved in 5 g of alcohol with a volume concentration of 99%, and then added to the wet silver-coated copper powder and stirred; The wet silver-coated copper powder obtained from the above separation step is dried at 60°C for 12 hours to finally obtain silver-coated copper conductive powder with anti-aging performance (high tap density single-particle dispersed silver-coated copper powder). The particle size distribution of this silver-coated copper conductive powder is D 10 is 2.5, D 50 is 4.0, D 90The tap density is 6.9 and the apparent density is 6.3. The silver content tested is 25%.
[0023] Comparative Example 4: Compared with Example 1, other types of copper powder were replaced while others remained unchanged; It includes the following steps: 1 kg of high-temperature pressure-sensitive sintered copper powder with a particle size distribution of D 10 being 0.8, D 50 being 2.0, D 90 being 5.1 and an apparent density of 5.2; this copper powder was added to 1 kg of anhydrous ethanol solvent with a volume concentration of 99% and mixed, then 3 g of triethanolamine solution with a volume concentration of 99% was added. While stirring, it was heated to 35°C - 40°C, stirred for 10 min, then ultrasonically cleaned for 3 - 5 min, then the copper powder and anhydrous ethanol were separated, and then 1 kg of anhydrous ethanol with a volume concentration of 99% was added and mixed and stirred again; after repeating this operation three times, the coating agent and other impurities on the surface of the copper powder were all cleaned, and finally separated from the anhydrous ethanol; 5 L of deionized water was added to the copper powder, stirring was started, and while stirring, the overall solution temperature was controlled at 35°C - 40°C; subsequently, 5 g of modified polyether dispersant was added, after adding 1.2 g of tetracarboxyphenyl porphyrin (TCPP) and stirring for 5 min, 0.5 g of tin chloride solution was added to the solution, after stirring for 10 min, 3 g of thiophene-3-carboxylic acid was added, then 12 g of tartaric acid was added, and finally 23 g of triethanolamine solution with a volume concentration of 99% was added. While stirring, it was kept at a constant temperature of 35°C - 40°C and stirred for 10 min; 472 g of silver nitrate was dissolved in 4 L of deionized water, while stirring, it was heated to 35°C - 40°C; The silver nitrate solution was slowly added to the copper powder solution, and the whole process was controlled within 15 min, and the temperature was controlled at 35°C - 40°C; Then silver-coated copper powder was obtained; the silver-coated copper powder was filtered out and washed with deionized water 3 times, and the conductivity reached below 30; 0.3 g of coating agent oleic acid was dissolved in 5 g of alcohol with a volume concentration of 99%, and then added to the wet silver-coated copper powder and stirred; The wet silver-coated copper powder separated in the above step was dried at 60°C for 12 h, and finally silver-coated copper conductive powder with anti-aging performance (silver-coated copper powder with high apparent density and single-particle dispersion) was obtained. The particle size distribution of this silver-coated copper conductive powder was D 10 being 1.2, D 50 being 2.5, D 90 being 5.9 and the apparent density is 4.5. The silver content tested is 30%.
[0024] Performance test: The silver-coated copper conductive powders obtained in Example 1 and Comparative Examples 1, 2, 3, and 4 were made into HJT pastes, and compared with the paste data on the experimental production line. The effects are shown in Table 1 below: Table 1: Electrical performance data of the battery prepared from the powder involved in the present invention into HJT paste
[0025] Table 2: Comparison of the efficiency before and after the aging test of the HJT battery encapsulated into a module made of the powder involved in the present invention under the 500h high-temperature and high-humidity test (double 85 experiment)
[0026] It can be seen from the data in Tables 1-2 that compared with the production line data, the electrical performance of the HJT battery made in Example 1 and the subsequent double 85 aging test data are both on a par with the performance of the production line paste and can meet the performance requirements.
[0027] In Comparative Example 1, since less silver nitrate was added, the silver content of the silver-coated copper decreased, and finally the electrical performance of the HJT battery made was slightly worse. In addition, in the subsequent electrical performance aging test, the performance also decreased significantly and could not meet the production line requirements.
[0028] In Comparative Example 2, since the key dispersant was removed, the overall particle size distribution and tapped density of the silver-coated copper did not reach the ideal state, and finally problems such as wire breakage and ghost printing occurred in the later printing of the prepared paste, which could not meet the production line requirements.
[0029] In Comparative Example 3, since the key silver layer binder was removed, the silver-coated copper powder prepared had a slightly lower silver content, and the bonding effect between the silver layer and copper was not good. The electrical performance of the prepared HJT paste was also low. Moreover, due to the poor bonding strength between the silver layer and copper, there was a sharp drop in the subsequent double 85 aging test data.
[0030] In Comparative Example 4, since the copper powder was replaced, the finally prepared silver-coated copper powder was in an agglomerated state, and the particle size distribution and tapped density of the silver-coated copper did not reach the ideal state. Finally, problems such as wire breakage and ghost printing occurred in the later printing of the prepared paste, which could not meet the production line requirements.
[0031] The above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.
Claims
1. A method for preparing silver-coated copper conductive powder with anti-aging performance, characterized in that: The following steps are involved: S1. Mix copper powder and anhydrous ethanol solvent with a volume concentration of 99% in a mass ratio of 1:(1-2), then add an alcohol amine compound solution with a volume concentration of 99%, wherein the amount of the alcohol amine compound solution added is 0.2%-0.5% of the mass of the copper powder, and heat to 35°C-40°C while stirring, and stir for 10 minutes; Then, ultrasonic cleaning is performed for 3-5 minutes to separate the copper powder and the solution, and then anhydrous ethanol with a volume concentration of 99% is added in the same proportion and mixed and stirred; after repeating the ultrasonic cleaning and copper powder separation three times, the coating agent and impurities on the surface of the copper powder are cleaned, and finally separated from the anhydrous ethanol; The copper powder is a round solid single particle dispersed high crystalline powder with a particle size distribution of D 10 2.0-3.0, D 50 3.0-4.0, D 90 is 6.0-8.5, and the tap density is 5.5-6.5; The alcoholamine compound is selected from triethanolamine or diethanolamine, or a mixture of the two in any proportion; S2, adding deionized water to the copper powder obtained in the above step, the copper powder and the deionized water are mixed in a mass ratio of 1: (5-10), and the overall solution temperature is controlled at 35°C-40°C while stirring, and then adding a modified polyether dispersant, wherein the amount of the modified polyether dispersant added is 0.3%-2% of the mass of the copper powder; the modified polyether dispersant is selected from hydroxy acrylic acid modified polyether; Adding a water-soluble porphyrin compound, wherein the amount of the water-soluble porphyrin compound added is 0.1%-0.8% of the mass of the copper powder; After adding the water-soluble porphyrin compound and stirring for 5 minutes, a tin chloride solution is added to the solution, wherein the amount of tin chloride added is 0.03%-0.1% of the mass of the copper powder, and stirring is performed for 10 minutes; the water-soluble porphyrin compound is selected from aminotetraphenylporphyrin, or a derivative with a similar structure to aminotetraphenylporphyrin, or a mixture of the two in any proportion; Adding a thiophene compound, wherein the amount of the thiophene compound added is 0.1%-0.5% of the mass of the copper powder; the thiophene compound is selected from 2-thiopheneacetic acid or a thiophene chemical derivative with a similar structure; Adding an organic acid compound, wherein the amount of the organic acid compound added is 1%-3% of the mass of the copper powder, and the organic acid compound is selected from one of citric acid, oxalic acid, succinic acid, and tartaric acid or a mixture of several of them in any proportion; Finally, add 99% volume concentration of alcohol amine compound solution, the amount of alcohol amine compound solution added is 2%-5% of the mass of copper powder, stir while keeping the temperature at 35℃-40℃, stir for 10 minutes; S3, dissolving silver nitrate in deionized water, the mass ratio of silver nitrate to deionized water is 1: (5-10), the mass ratio of silver nitrate to copper powder is 1: (1.0-3.5), and heating to 35°C-40°C while stirring; S4, slowly adding the solution in S3 to the solution in S2, the whole process is controlled within 15-20 minutes, the temperature is controlled at 35°C-40°C, to obtain silver-coated copper powder; S5, filter the silver-coated copper powder and wash it with deionized water for 3 times, and the conductivity is ≤30. Wet silver-coated copper powder is obtained; S6, dissolving the coating agent in anhydrous ethanol, wherein the amount of the coating agent added is 0.03%-0.1% of the mass of the copper powder, and the amount of alcohol added is 3 times-20 times of the mass of the coating agent; then adding the coating agent to the wet silver-coated copper powder, stirring, and separating; The coating agent is selected from one of oleic acid, stearic acid, lauric acid, or a mixture of any proportion; S7, drying the wet silver-coated copper powder separated in the previous step at 60°C for 12 hours to obtain a silver-coated copper conductive powder with anti-aging performance. The particle size distribution of the silver-coated copper conductive powder is D 10 2.0-3.3, D 50 3.5-5.5, D 90 The tap density is 6.0-9.0, the tap density is 4.5-6.5, and the silver content is 20%-35%. The HJT slurry prepared using the silver-coated copper conductive powder with anti-aging performance has a Voc of 740.3 mV-740.8 mV and a Jsc of 38.69 mA / cm 2 -39.56 mA / cm 2 , FF is 82.66%-82.87%, Eta is 23.82%-23.87%, and the efficiency after aging experiment is 23.77%-23.81%.
2. The method for preparing a silver-coated copper conductive powder with anti-aging performance according to claim 1, characterized in that: The copper powder described in S1 is a round solid single-particle dispersed high-crystalline powder with a particle size distribution of D 10 2.0-3.0, D 50 is 3.5, D 90 The viscosity is 6.0-8.5, the tap density is 5.5-6.5, and the silver content is 20%-35%.
3. A silver-coated copper conductive powder with anti-aging performance, characterized in that: According to the method for preparing a silver-coated copper conductive powder with anti-aging performance according to claim 1 or 2, the particle size distribution of the silver-coated copper conductive powder is D 10 2.0-3.3, D 50 3.5-5.5, D 90 The tap density is 6.0-9.0, the tap density is 4.5-6.5, and the silver content is 20%-35%. The HJT slurry prepared using the silver-coated copper conductive powder with anti-aging performance has a Voc of 740.3 mV-740.8 mV and a Jsc of 38.69 mA / cm 2 -39.56mA / cm 2 , FF is 82.66%-82.87%, Eta is 23.82%-23.87%, and the efficiency after aging experiment is 23.77%-23.81%.