Glass frit for solar cell front paste and paste, monocrystalline silicon solar cell

Abstract

The application discloses a glass frit for a single-crystal silicon solar cell front paste, a paste, and a single-crystal silicon solar cell. The glass frit comprises 1-30 mol% of lithium oxide, 5-40 mol% of bismuth oxide, 5-40 mol% of lead oxide, 1-40 mol% of silicon oxide, and X, wherein X is any one or a mixture of several of copper oxide, cesium oxide, rubidium oxide, sodium oxide, potassium oxide, aluminum oxide, magnesium oxide, strontium oxide, tin oxide, zinc oxide, or tungsten oxide, and the molar content of any one of the oxides in X is 1-10 mol%, and the content of X is not more than 50 mol%. The conductive paste prepared by using the glass frit contains a lead-bismuth-silicon oxide glass system, the system has enhanced resistance to acetic acid attenuation, ensures a sintering window at a high-temperature fast-firing sintering temperature, and X has strong corrosiveness, so that a lower contact area can be obtained. The conductive paste has high resistance to acetic acid in a wide sintering window.

Description

Technical Field

[0001] This invention belongs to the field of solar cell paste technology, and particularly relates to a glass material and paste for the front side paste of a monocrystalline silicon solar cell, and a monocrystalline silicon solar cell. Background Technology

[0002] Photovoltaics, short for solar photovoltaic power generation system, is a new type of power generation system that uses the photovoltaic effect of solar cell semiconductor materials to directly convert solar radiation energy into electrical energy. It can operate independently or be connected to the grid. Solar photovoltaic power generation systems are divided into two categories: centralized systems, such as large-scale ground-mounted photovoltaic power generation systems in Northwest China; and distributed systems, such as rooftop photovoltaic power generation systems for industrial and commercial enterprises and residential buildings.

[0003] A photovoltaic (PV) module is a smallest, indivisible assembly of photovoltaic cells that is encapsulated and internally interconnected, and capable of individually providing direct current (DC) output. PV modules are the core and most important component of a solar power generation system.

[0004] Photovoltaic modules, which perform photoelectric conversion, need to be used outdoors for 25 to 30 years, constantly exposed to complex environments such as light, heat, oxygen, and water. This requires the module materials to have good weather resistance. Among the various materials in the module, the encapsulation material, which plays a role in encapsulation, is currently the most commonly used encapsulation material on the market. EVA (Ethylene-vinyl acetate) film is a polymer of ethylene and vinyl acetate. However, the chemical structure of this material itself is not stable. During long-term use, it will undergo a hydrolysis reaction to produce acetic acid. Acetic acid will come into contact with the inorganic substances on the electrodes, causing the internal resistance of the electrodes to increase and thus reducing efficiency.

[0005] Therefore, in response to the problem of acetic acid corrosion resistance in photovoltaic cells, solar cell manufacturers require front-side silver paste to have higher resistance to acetic acid degradation, while ensuring a better sintering window for the front-side silver paste. This has been a long-term goal for industry professionals. Summary of the Invention

[0006] To address the above technical problems, this invention provides a glass material and paste for the front-side paste of a monocrystalline silicon solar cell, as well as a monocrystalline silicon solar cell, which improves the solar cell's resistance to acetic acid degradation.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] A glass frit for the front-side paste of a monocrystalline silicon solar cell, calculated by molar percentage, comprises: 1-30 mol% lithium oxide, 4-40 mol% bismuth oxide, 5-40 mol% lead oxide, 1-40 mol% silicon oxide, and X, wherein X is any one or a mixture of several of copper oxide, cesium oxide, rubidium oxide, sodium oxide, potassium oxide, aluminum oxide, magnesium oxide, strontium oxide, tin oxide, zinc oxide, or tungsten oxide, and the molar content of any oxide in X is 1-10 mol%, and the content of X does not exceed 50 mol%.

[0009] More preferably, the glass material comprises: 4-30 mol% lithium oxide, 4-30 mol% bismuth oxide, 10-30 mol% lead oxide, 1-40 mol% silicon oxide, and X content not exceeding 36 mol%.

[0010] Using the same inventive concept, this invention also provides a method for preparing glass frit for the front-side paste of monocrystalline silicon solar cells, including a high-temperature melt-cooling method, wherein the high-temperature melt-cooling method specifically includes:

[0011] Step 1: Mix the raw materials of the glass according to the composition ratio of the glass, and then melt them at 1000-1400℃ for 90 minutes to form a liquid glass mixture;

[0012] Step 2: Cool, grind, dry, and sieve the liquid glass mixture to obtain glass material.

[0013] Preferably, in step one, a double-roller or uniform speed mixer is used to mix the glass raw materials evenly; and / or in step two, the cooling treatment is carried out using pure water cooling or stainless steel plate cooling; and / or the grinding is carried out using a wet ball mill.

[0014] Based on the same inventive purpose, the present invention also provides a front-side paste for monocrystalline silicon solar cells, including glass frit for front-side paste of monocrystalline silicon solar cells or glass frit obtained by the above preparation method;

[0015] Preferably, the front-side paste of the monocrystalline silicon solar cell also includes conductive powder and an organic carrier.

[0016] The composition, by mass percentage, is 1.1-6 wt% glass, 86-91 wt% conductive powder, and 6-12 wt% organic carrier.

[0017] Preferably, the conductive powder is silver powder.

[0018] Preferably, the organic carrier comprises an organic resin and additives.

[0019] Preferably, the additives include dispersants, surfactants, and thixotropic agents.

[0020] Preferably, the resin is any one or a combination of two or more of diethylene glycol butyl ether acetate, dimethyl adipate, ethyl cellulose, and acrylic modified resin.

[0021] The dispersant is selected from any one or more of the following: 12-hydroxystearic acid, oleamide, erucamide, sodium tripolyphosphate, sodium pyrophosphate, alkylbenzene sulfonate, dialkyl sulfosuccinate, polyoxyethylene alkylphenol ether, and vinyl bis-stearamide.

[0022] The surfactant is selected from any one or more of the following: polyethylene glycol, sodium linear alkylbenzene sulfonate, sodium lauryl sulfate, lauroyl glutamic acid, nonylphenol polyoxyethylene ether, lignin sulfonate, alkyl sulfonate, fatty alcohol polyoxyethylene ether, and sodium fatty alcohol polyoxyethylene ether sulfate.

[0023] The thixotropic agent is selected from any one or more of the following: organobentonite, polyamide wax, modified hydrogenated castor oil, fumed silica, and polyethylene wax.

[0024] A method for preparing a front-side paste for monocrystalline silicon solar cells involves uniformly mixing organic resin, additives, glass frit, and conductive powder, and then uniformly dispersing the mixture using a two-roll mill to obtain a solar cell front-side paste with a fineness of less than 7 micrometers.

[0025] A monocrystalline silicon solar cell includes electrodes or grid lines made from a paste on the front side of the monocrystalline silicon solar cell, wherein the monocrystalline silicon solar cell can be a PERC cell.

[0026] Because the present invention adopts the above technical solution, it has the following advantages and positive effects compared with the prior art:

[0027] The glass frit for front-side silver paste of monocrystalline silicon solar cells provided by this invention comprises a lead-bismuth-silicon oxide system containing silicon oxide, lead oxide, and bismuth oxide. This system enhances resistance to corrosion by acetic acid solution while ensuring a sintering window under high-temperature rapid sintering conditions. Furthermore, the glass contains lithium oxide and X, where X is any one or more combinations of copper oxide, cesium oxide, rubidium oxide, sodium oxide, potassium oxide, aluminum oxide, magnesium oxide, strontium oxide, tin oxide, zinc oxide, or tungsten oxide. These oxides have low glass transition and softening temperatures, exhibit strong corrosivity to the silicon nitride passivation layer, and maintain fluidity, thus achieving a wide contact area and good contact performance. Lithium oxide also exhibits strong corrosivity to the passivation layer, resulting in good contact performance between the paste and the battery substrate. Therefore, the glass frit of this invention exhibits a more stable sintering window to sintering temperature variations, along with excellent contact performance and improved resistance to acetic acid solution degradation. Therefore, the silver paste of the present invention can be used to fabricate fine grids in a single printing process or in a distributed printing process, and can also be applied to monocrystalline PERC silicon wafers. Detailed Implementation

[0028] This invention addresses the problem of improving the resistance of solar cells to acetic acid degradation by proposing a glass material for the front-side paste of solar cells, as well as the front-side paste and solar cell wafers. The glass material proposed in this invention can not only be applied to the solar cell paste to improve the cell's resistance to acetic acid degradation, but also corrode the cell passivation film, increasing the contact area between the paste and the cell substrate, thereby obtaining a lower contact area, and can be applied to monocrystalline silicon solar cells.

[0029] A glass frit for the front-side paste of a monocrystalline silicon solar cell, calculated by molar percentage, comprises: 1-30 mol% lithium oxide, 4-40 mol% bismuth oxide, 5-40 mol% lead oxide, 1-40 mol% silicon oxide, and X, wherein X is any one or a mixture of several of copper oxide, cesium oxide, rubidium oxide, sodium oxide, potassium oxide, aluminum oxide, magnesium oxide, strontium oxide, tin oxide, zinc oxide, or tungsten oxide, and the molar content of any oxide in X is 1-10 mol%. For example, if X is a mixture of copper oxide, cesium oxide, and potassium oxide, then the molar content of copper oxide is 1-10 mol%, the molar content of cesium oxide is also 1-10 mol%, and the molar content of potassium oxide is also 1-10 mol%, but the content of X in the glass frit does not exceed 50%.

[0030] The glass system employed contains a lead-bismuth-silicon oxide system, which enhances resistance to acetic acid degradation while ensuring a suitable sintering window at high-temperature, rapid sintering temperatures. The X oxide in the glass frit exhibits low glass transition and softening temperatures, providing good fluidity to the substrate during high-temperature sintering, thus achieving a wide contact area. Simultaneously, both X and lithium oxide exhibit strong corrosiveness to the passivation layer silicon nitride, resulting in a smaller contact area.

[0031] The above-mentioned method for preparing glass frit for the front-side paste of monocrystalline silicon solar cells includes a high-temperature melt-cooling method, which specifically includes:

[0032] Step 1: According to the composition ratio of the glass material, mix the raw materials of the glass material evenly using a double roller or uniform speed mixer, and then melt them at 1000-1400℃ for 90 minutes to form a liquid glass mixture;

[0033] Step 2: Cool the liquid glass mixture with cooling water or stainless steel plates. For example, the liquid glass mixture is treated with cooling water or cooled with stainless steel plates. Then, it is ground, dried and sieved to obtain the main glass material and the secondary glass material.

[0034] The grinding can be performed using a wet ball mill.

[0035] The present invention also provides a front-side paste for monocrystalline silicon solar cells, comprising a glass frit for the front-side paste of monocrystalline silicon solar cells or a glass frit obtained by the above preparation method, as well as conductive powder and an organic carrier.

[0036] The composition, by mass percentage, is 1.1-6 wt% glass, 86-91 wt% conductive powder, and 6-12 wt% organic carrier.

[0037] Preferably, the conductive powder is entirely silver powder, and the shape of the silver powder can be spherical granular silver powder, or rod-shaped or flake-shaped granular silver powder, or any combination of the above shapes.

[0038] Preferably, the organic carrier comprises an organic resin and additives, wherein the additives include dispersants, surfactants, and thixotropic agents;

[0039] The resin is any one or a combination of two or more of diethylene glycol butyl ether acetate, dimethyl adipate, ethyl cellulose, and acrylic modified resin.

[0040] The dispersant is selected from any one or a combination of several of the following: 12-hydroxystearic acid, oleamide, erucamide, sodium tripolyphosphate, sodium pyrophosphate, alkylbenzene sulfonate, dialkyl sulfosuccinate, polyoxyethylene alkylphenol ether, and vinyl bis-stearamide.

[0041] The surfactant is selected from any one or a combination of several of the following: polyethylene glycol, sodium linear alkylbenzene sulfonate, sodium lauryl sulfate, lauroyl glutamic acid, nonylphenol polyoxyethylene ether, lignin sulfonate, alkyl sulfonate, fatty alcohol polyoxyethylene ether, and sodium fatty alcohol polyoxyethylene ether sulfate.

[0042] The thixotropic agent is selected from any one or more of the following: organobentonite, polyamide wax, modified hydrogenated castor oil, fumed silica, and polyethylene wax.

[0043] The above-described method for preparing the front-side paste for monocrystalline silicon solar cells involves uniformly mixing organic resin, additives, glass frit, and conductive powder, and then uniformly dispersing the mixture using a two-roll mill to obtain a solar cell front-side paste with a fineness of less than 7 micrometers. During paste preparation, the main and secondary glass frits, conductive powder, and organic carrier are all uniformly mixed. Finally, the mixture is screen-printed onto the monocrystalline silicon solar cell wafer and sintered to form a lead-bismuth-silicon oxide system containing lithium oxide and X. The lead-bismuth-silicon oxide system enhances resistance to acetic acid solution corrosion while ensuring a suitable sintering window under high-temperature rapid firing conditions. Other oxides have low glass transition and softening temperatures, exhibiting strong corrosiveness to the substrate while maintaining fluidity, thus achieving a wide contact area and good contact performance.

[0044] A monocrystalline silicon solar cell includes electrodes or grid lines fabricated from a front-side paste for the monocrystalline silicon solar cell, and the monocrystalline silicon solar pad can be a PERC cell. Generally, the front-side paste for a solar cell is screen-printed onto a monocrystalline silicon wafer, and then sintered at high temperature (typically 400-900℃). This process causes the organic carrier to volatilize, increasing the glass activity and allowing it to corrode the passivation film on the monocrystalline silicon solar cell. If the sintering temperature is too high or the sintering time is too long, the glass continues to corrode, the sintering window is over-burned, resulting in low on-voltage and low efficiency in electrical performance. Therefore, a glass frit containing a mixture of lead oxide, bismuth oxide, silicon oxide, and X can control the temperature of the passivation film reaction, thereby ensuring the sintering window is within the high-temperature, rapid sintering temperature range.

[0045] The following detailed description, in conjunction with specific embodiments, provides a glass frit and paste for the front-side paste of a monocrystalline silicon solar cell, and the monocrystalline silicon solar cell itself, as proposed in this invention. The advantages and features of this invention will become clearer from the following description.

[0046] glass material

[0047] Example A1

[0048] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 5 mol% lead oxide, 40 mol% bismuth oxide, 40% silicon oxide, 10 mol% lithium oxide and 5 mol% X, wherein X comprises 1 mol% copper oxide, 1 mol% cesium oxide, 1 mol% aluminum oxide, 1 mol% sodium oxide and 1 mol% magnesium oxide.

[0049] Example A2

[0050] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 40 mol% lead oxide, 5 mol% bismuth oxide, 1 mol% silicon oxide, 4 mol% lithium oxide, and 50 mol% X, wherein X comprises 10 mol% copper oxide, 10 mol% cesium oxide, 10 mol% aluminum oxide, 10 mol% sodium oxide, and 10 mol% magnesium oxide.

[0051] Example A3

[0052] A glass frit for the front-side paste of a monocrystalline silicon solar cell, comprising, by molar percentage: 30 mol% lead oxide, 5 mol% bismuth oxide, 20 mol% silicon oxide, 20 mol% lithium oxide and 25 mol% X, wherein X comprises 5 mol% copper oxide, 5 mol% cesium oxide, 5 mol% aluminum oxide, 5 mol% sodium oxide and 5 mol% magnesium oxide.

[0053] Example A4

[0054] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 5 mol% lead oxide, 30 mol% bismuth oxide, 28 mol% silicon oxide, 10 mol% lithium oxide and 27 mol% X, wherein X comprises 1 mol% copper oxide, 10 mol% cesium oxide, 10 mol% aluminum oxide, 1 mol% sodium oxide and 5 mol% magnesium oxide.

[0055] Example A5

[0056] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 25 mol% lead oxide, 25 mol% bismuth oxide, 1 mol% silicon oxide, 13 mol% lithium oxide and 36 mol% X, wherein X comprises 10 mol% copper oxide, 1 mol% cesium oxide, 5 mol% aluminum oxide, 10 mol% sodium oxide and 10 mol% magnesium oxide.

[0057] Example A6

[0058] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 30 mol% lead oxide, 4 mol% bismuth oxide, 40 mol% silicon oxide, 4 mol% lithium oxide, and 22 mol% X, wherein X comprises 5 mol% copper oxide, 10 mol% cesium oxide, 1 mol% aluminum oxide, 5 mol% sodium oxide, and 1 mol% magnesium oxide.

[0059] Example A7

[0060] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 25 mol% lead oxide, 30 mol% bismuth oxide, 17 mol% silicon oxide, 1 mol% lithium oxide and 27 mol% X, wherein X comprises 1 mol% copper oxide, 5 mol% cesium oxide, 10 mol% aluminum oxide, 10 mol% sodium oxide and 1 mol% magnesium oxide.

[0061] Example A8

[0062] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 15 mol% lead oxide, 8 mol% bismuth oxide, 20 mol% silicon oxide, 30 mol% lithium oxide and 27 mol% X, wherein X comprises 10 mol% copper oxide, 1 mol% cesium oxide, 1 mol% aluminum oxide, 10 mol% sodium oxide and 5 mol% magnesium oxide.

[0063] Example A9

[0064] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 10 mol% lead oxide, 29 mol% bismuth oxide, 10 mol% silicon oxide, 20 mol% lithium oxide and 31 mol% X, wherein X comprises 5 mol% copper oxide, 10 mol% cesium oxide, 5 mol% aluminum oxide, 1 mol% sodium oxide and 10 mol% magnesium oxide.

[0065] Comparative Example B1

[0066] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 40 mol% lead oxide, 5 mol% bismuth oxide, 40 mol% silicon oxide, and 15 mol% lithium oxide.

[0067] Comparative Example B2

[0068] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 1 mol% lead oxide, 40 mol% bismuth oxide, 30 mol% silicon oxide, 15 mol% lithium oxide and 14 mol% X, wherein X comprises 5 mol% copper oxide, 3 mol% cesium oxide, 2 mol% aluminum oxide, 2 mol% sodium oxide and 2 mol% magnesium oxide.

[0069] Comparative Example B3

[0070] A glass frit for the front-side paste of a monocrystalline silicon solar cell comprises, by molar percentage: 40 mol% lead oxide, 15 mol% bismuth oxide, 30 mol% lithium oxide and 15 mol% X, wherein X comprises 2 mol% copper oxide, 3 mol% cesium oxide, 3 mol% aluminum oxide, 4 mol% sodium oxide and 3 mol% magnesium oxide.

[0071] The specific components and contents of the glass raw materials used are detailed in Table 1 below (unit: mole percentage, mol%).

[0072] Table 1

[0073]

[0074] The raw materials were obtained according to the proportions in Table 1. Then the raw materials of the glass were mixed separately and melted at 1000℃ for 60 minutes to obtain liquid glass mixture.

[0075] The liquid glass mixture is then cooled by a stainless steel plate, followed by planetary ball milling, drying, and sieving to obtain glass material with a particle size of 1.4-2.4μm.

[0076] front slurry

[0077] The conductive silver powder and organic carrier used in the following embodiments are the same. The conductive silver powder is commercially available spherical silver powder, and the organic carrier is shown in Table 2. All of these experiments were conducted using commercially available materials.

[0078] Table 2

[0079]

[0080] Then, the glass frits of Examples 1-9 and Comparative Examples 1-3 were mixed with the organic carrier, silver powder and organic carrier in Table 2 according to Table 3, and ground using a double roller milling method to obtain a slurry with a fineness of less than 7 micrometers.

[0081] Table 3

[0082]

[0083] The paste prepared according to the front paste formulation listed in Table 3 was screen-printed onto a monocrystalline silicon substrate under the same conditions, and then sintered at 800°C for 1 minute to form a monocrystalline silicon solar cell. The conversion efficiency of Examples A1-A9 and Comparative Examples B1-B3 was tested using an IV meter under the same testing standard, and the EI (electroluminescence) of Examples A1-A9 and Comparative Examples B1-B3 was tested using an EL meter under the same testing standard. The results are detailed in Table 4.

[0084] Table 4

[0085]

[0086]

[0087] Where Voc is the open-circuit voltage, Isc is the short-circuit current, Rs is the series resistance, Rsh is the parallel resistance, FF is the fill factor, and Ncell is the conversion efficiency.

[0088] The results in Table 4 show that the series resistance Rs of the embodiments is lower than that of Comparative Example B1, and the parallel resistance Rsh of the embodiments is higher than that of Comparative Example B1, indicating that the addition of oxide mixture X improves the contact performance of the conductive paste. The normal EL values ​​in the embodiments indicate that the embodiments have a better sintering window. With a better sintering window, the open-circuit voltage of the solar cell is relatively lower. The slightly lower open-circuit voltages of embodiments A1-A9 compared to Comparative Examples B2 and B3 also indirectly demonstrate that the glass system of this invention can guarantee a better sintering window.

[0089] To further illustrate the acetic acid degradation resistance of the fabricated monocrystalline silicon solar cell, the cell was simulated to be exposed to a complex environment including light, heat, oxygen, and water over a long period. Specific settings:

[0090] Solution preparation: Add 125g of potassium chloride and 194g of purified water to a 20-liter sealed container and mix, then add 6.3g of acetic acid solution;

[0091] Prepare a basket suitable for the size of the silicon wafers. According to the requirements for placing the wafers, all wafers should be aligned with the same front and back orientation and with the main grid line perpendicular to the bottom. Using the bottom of the basket as a reference, the height from the bottom of the wafer to the bottom of the wafer should be 1.7cm. The spacing between the grids should be about 2mm wide. The order of placing the wafers is blank wafer-dummy wafer-blank wafer-experiment wafer-blank wafer-standard wafer, repeating the pattern. Place the basket with the wafers in the middle of the sealed box, with the liquid level about 1.7cm away from the wafers. Gently transfer the sealed box into the oven and use a constant current source to supply the fan inside the sealed box. Place the box at 90℃ for 15 hours.

[0092] Then, the battery cells were removed, and their performance data and acetic acid degradation values ​​were tested after the acetic acid test. See Table 5 for details.

[0093] Table 5

[0094]

[0095]

[0096] Table 5 shows that the acetic acid degradation resistance of Comparative Example B1 is slightly lower than that of Comparative Examples B2-B3. However, the acetic acid degradation resistance of Examples A1-A9 is lower than that of Comparative Examples B1-B3, and meets the battery manufacturer's requirement that the acetic acid degradation resistance of the cells be within 15-20%. The open-circuit voltage Voc of the cells before and after immersion in acetic acid remains basically unchanged, while the short-circuit current Isc, fill factor FF, and conversion efficiency decrease. Table 6 shows the changes in short-circuit current Isc, fill factor FF, and conversion efficiency Ncell before and after immersion in acetic acid. The results in Table 6 show that the changes in short-circuit current, fill factor, and conversion efficiency of the examples are all smaller than those of the comparative examples, further demonstrating that the examples have excellent resistance to acetic acid degradation and low acetic acid degradation resistance.

[0097] Table 6

[0098]

[0099] The embodiments of the present invention have been described in detail above with reference to the examples, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they shall still fall within the protection scope of the present invention.

Claims

1. A glass frit for the front-side paste of a monocrystalline silicon solar cell, characterized in that, The glass material, calculated by molar percentage, comprises: 1-13 mol% lithium oxide, 4-30 mol% bismuth oxide, 10-30 mol% lead oxide, 1-40 mol% silicon oxide, and 22-36 mol% X, wherein X is a mixture of copper oxide, cesium oxide, sodium oxide, aluminum oxide, and magnesium oxide, and the molar content of any one oxide in X is 1-10 mol.

2. A method for preparing glass frit for the front-side paste of a monocrystalline silicon solar cell as described in claim 1, characterized in that, This includes a high-temperature melting and cooling method, specifically comprising: Step 1: Mix the raw materials of the glass according to the composition ratio of the glass, and then melt them at 1000-1400°C for 90 minutes to form a liquid glass mixture; Step 2: Cool, grind, dry, and sieve the liquid glass mixture to obtain glass material.

3. The method for preparing glass frit for the front-side paste of monocrystalline silicon solar cells according to claim 2, characterized in that, In step one, a double roller or uniform speed mixer is used to mix the glass raw materials evenly; and / or in step two, the cooling process is carried out using pure water cooling or stainless steel plate cooling; and / or the grinding is carried out using a wet ball mill.

4. A paste for the front side of a monocrystalline silicon solar cell, characterized in that, This includes the glass frit for the front paste of a monocrystalline silicon solar cell as described in claim 1, or the glass frit obtained by the preparation method described in claim 2 or 3.

5. The front-side paste for monocrystalline silicon solar cells according to claim 4, characterized in that, The front paste of the monocrystalline silicon solar cell also includes conductive silver powder and an organic carrier.

6. The front-side paste for monocrystalline silicon solar cells according to claim 5, characterized in that, The organic carrier includes an organic resin and an additive, wherein the additive includes any one or a mixture of several of a dispersant, a surfactant, and a thixotropic agent.

7. A method for preparing the front-side paste of a monocrystalline silicon solar cell as described in claim 6, characterized in that, Organic resin, additives, glass frit, and conductive silver powder are mixed evenly and then dispersed evenly using a two-roll mill to obtain a front-side paste for monocrystalline silicon solar cells with a fineness of less than 7 micrometers.

8. A monocrystalline silicon solar cell, characterized in that, Electrodes made from the front paste of a monocrystalline silicon solar cell as described in any one of claims 4-6 or the front paste of a monocrystalline silicon solar cell obtained by the preparation method described in claim 7.

9. A monocrystalline silicon solar cell, characterized in that, The grid lines are made from the front-side paste of a monocrystalline silicon solar cell as described in any one of claims 4-6 or from the front-side paste of a monocrystalline silicon solar cell obtained by the preparation method described in claim 7.

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