Glass powder silver paste suitable for laser grooving topcon cell and preparation method and application thereof

Abstract

The application belongs to the field of photovoltaic cell electrode materials, and provides a glass powder silver paste suitable for laser grooving TOPCon cells and a preparation method and application thereof. The application prepares a stripping zirconium phosphate nanosheet paste with introduced acrylate functional groups on the surface, and obtains a core-shell dispersion with a sol core and a crosslinked organic shell. Ethyl cellulose is dissolved in an organic solvent to form an organic carrier, and after cooling, a dispersant, a nanosheet paste and a core-shell dispersion are added to obtain a functional carrier. Then, the functional carrier is mixed with customized glass powder, spherical silver powder and titanate interface promoter to obtain a silver paste. The silver paste is used for metalization printing in the grooving area and sintering in an inert atmosphere, and the glass phase reaction and flow can be controlled and adjusted. The nanosheet limits the deep penetration and local over-corrosion of the glass phase, the core-shell structure is stable in the drying stage and forms a network in situ in the sintering stage, and cooperates to promote wetting, densification and interface bonding, so as to improve the line integrity and reduce the contact and series loss.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of photovoltaic cell electrode materials, and relates to a glass powder silver paste suitable for a laser grooving TOPCon cell and a preparation method and application thereof. BACKGROUND

[0002] TOPCon cells (tunnel oxide passivated contact cells) are widely used in high-efficiency cell routes due to their excellent passivation contact structure, but in the process of module interconnection and metallization, in order to obtain lower series resistance and higher current collection capability, the surface passivation layer often needs to be broken or weakened in local areas by means of laser grooving and the like to form a window suitable for electrode penetration. Laser grooving can introduce microstructures, recast layers and defect-rich zones on the silicon surface, and expose more active silicon matrix or thin oxide layer interfaces, so that the wetting, reaction and diffusion behaviors in the subsequent silver paste printing and sintering processes are significantly different from those in the ungrooved areas.

[0003] The existing glass powder silver paste for crystalline silicon cell metallization mainly relies on the softening flow and interfacial reaction of the glass phase during sintering to realize the cleaning of the silicon surface, the removal of residual oxides and the formation of stable electrical contact, but in the laser grooving TOPCon structure, if the reactivity and fluidity of the glass phase are not properly controlled, excessive penetration and local enrichment may occur in the groove, leading to increased corrosion, uneven contact morphology, deformed line boundaries and increased hole defects, thereby causing fluctuations in contact resistance, rising series loss and performance dispersion; on the contrary, if the glass phase is not reactive enough, it may not be fully cleaned, wetted or have poor interfacial connectivity, resulting in unstable contact and decreased reliability. At the same time, the depth variation and edge roughness caused by laser grooving also make the silver paste more prone to problems such as solvent migration, component stratification, sedimentation and mismatch between thixotropic windows during printing and drying, further amplifying the risk of defects after sintering. SUMMARY

[0004] In view of the deficiencies of the prior art, the purpose of the present application is to provide a glass powder silver paste suitable for a laser grooving TOPCon cell and a preparation method and application thereof. A surface-functionalized exfoliated zirconium phosphate nanosheet slurry and a core-shell dispersion with a sol core / organic shell structure are prepared and introduced into an ethyl cellulose organic carrier system, and then matched with a customized glass powder, spherical silver powder and titanate interfacial promoter to prepare the paste. The silver paste is stable and shaped during printing and drying, and realizes the synergistic regulation of the flow and interfacial reaction of the glass phase during sintering, inhibits deep penetration and over-corrosion in the groove, and improves the consistency and reliability of the electrical contact, thereby meeting the needs of actual production.

[0005] To achieve this purpose, the technical scheme adopted by the present application is as follows:

[0006] In a first aspect, the present application provides a preparation method of a glass powder silver paste suitable for a laser grooving TOPCon cell, the preparation method comprising:

[0007] S1, mixing zirconium oxychloride octahydrate and deionized water to obtain a zirconium salt solution, adding a phosphoric acid solution to the zirconium salt solution and stirring and aging, drying to obtain α-ZrP powder, mixing the α-ZrP powder, anhydrous ethanol and n-butylamine to obtain a nanosheet dispersion liquid, mixing methacryloyloxypropyl trimethoxysilane, second deionized water and glacial acetic acid to obtain a pre-hydrolysis solution, adding the pre-hydrolysis solution to the nanosheet dispersion liquid to obtain mZrP-MA dry powder, mixing the mZrP-MA dry powder and diethylene glycol butyl ether acetate to obtain mZrP-MA slurry;

[0008] S2, mixing diethylene glycol butyl ether acetate, tetraethyl orthosilicate, triethyl phosphate, trimethyl borate and anhydrous ethanol to obtain solution A, adding an aqueous acetic acid solution to solution A to obtain a sol nucleus, mixing isododecane and Span 80 with the sol nucleus and dispersing to obtain a W / O dispersion system, mixing methyl methacrylate, glycidyl methacrylate and ethylene glycol dimethacrylate with azobisisobutyronitrile to obtain a shell monomer liquid, adding the shell monomer liquid to the W / O dispersion system and reacting, adding diethylene glycol butyl ether acetate and stirring and standing to obtain a dispersion;

[0009] S3, mixing ethyl cellulose and diethylene glycol butyl ether acetate, sequentially adding polymethyl lauryl methacrylate, mZrP-MA slurry and the dispersion to obtain an organic carrier, mixing glass powder, spherical silver powder and tetrabutyl titanate with the organic carrier to obtain a glass powder silver paste suitable for a laser grooving TOPCon cell.

[0010] Specifically comprising:

[0011] S1, mixing zirconium oxychloride octahydrate and deionized water to obtain a zirconium salt solution, heating to a first temperature under a nitrogen atmosphere, adding a phosphoric acid solution to the zirconium salt solution while stirring, then heating to a second temperature to obtain an α-ZrP precipitate slurry, centrifuging, washing and drying to obtain α-ZrP powder, mixing the α-ZrP powder, anhydrous ethanol and n-butylamine, stirring at a third temperature to obtain an intercalation slurry, shearing and dispersing the intercalation slurry to obtain a nanosheet dispersion liquid, mixing methacryloyloxypropyl trimethoxysilane, second deionized water and glacial acetic acid to obtain a pre-hydrolysis solution, adding the pre-hydrolysis solution to the nanosheet dispersion liquid, stirring and reacting at a fourth temperature, centrifuging, washing and drying to obtain mZrP-MA dry powder, mixing the mZrP-MA dry powder and diethylene glycol butyl ether acetate to obtain mZrP-MA slurry;

[0012] S2, mixing diethylene glycol butyl ether acetate, tetraethyl orthosilicate, triethyl phosphate, trimethyl borate with anhydrous ethanol to obtain solution A, adding aqueous acetic acid dropwise to solution A under room temperature and continuing to stir, then sealing and aging to obtain sol-gel nucleus, mixing isododecane, Span 80 with the sol-gel nucleus and dispersing to obtain a W / O dispersion system, mixing methyl methacrylate, glycidyl methacrylate, ethylene glycol dimethacrylate with azobisisobutyronitrile to obtain a shell monomer liquid, adding the shell monomer liquid to the W / O dispersion system, reacting under nitrogen atmosphere at a fifth temperature to obtain a hydrocarbon phase dispersion liquid, adding diethylene glycol butyl ether acetate to the hydrocarbon phase dispersion liquid, discarding the upper layer after stirring and standing, and continuing to add diethylene glycol butyl ether acetate to the lower layer dispersion phase and stirring and standing, repeating 2-3 times to obtain a dispersion;

[0013] S3, mixing ethyl cellulose with diethylene glycol butyl ether acetate and mixing uniformly at a fifth temperature, adding poly lauryl methacrylate, mZrP-MA slurry and the dispersion in sequence after cooling to obtain an organic carrier, mixing glass powder, spherical silver powder and tetrabutyl titanate with the organic carrier, vacuum defoaming and three-roll grinding to obtain a glass powder silver paste suitable for a laser grooving TOPCon cell.

[0014] In step S1, zirconium oxychloride octahydrate exists in the form of zirconium-containing complex ions after being dissolved in water, and coordination substitution and polycondensation precipitation occur after adding phosphoric acid, the zirconium center is connected with the phosphate group through bonding to form a layered zirconium phosphate skeleton, and the layered structure is further ordered and the defect density is reduced during subsequent constant temperature aging, thereby obtaining α-type zirconium phosphate. The layered material has exchangeable proton sites between the layers, and after the addition of n-butylamine, the n-butylamine is protonated by acid-base reaction and enters the interlayer to form ion pairs and hydrogen bond networks with the interlayer acidic sites, thereby increasing the interlayer spacing and weakening the interlayer electrostatic coupling, and the nanosheets are dispersed in the form of nanosheets. Methyl methacryloyloxypropyl trimethoxysilane is hydrolyzed to generate silanol in the presence of water and acetic acid, and the silanol reacts with the surface hydroxyl groups or P-OH sites of the nanosheets to form a local silicon-oxygen network through condensation. Finally, an organic silicon layer containing a methacryloyl group is introduced on the surface of the nanosheet, which reduces the driving force for restacking of the layers on one hand, and on the other hand, the nanosheets obtain solvation and interfacial compatibility in the subsequent organic carrier.

[0015] In step S2, tetraethyl orthosilicate hydrolyzes to form silanol units after introduced into the acidic aqueous phase, followed by condensation between silanols and gradual evolution of sol-gel nuclei. Triethyl phosphate hydrolyzes to form phosphate species containing P-O bonds under acidic conditions, which can condense with silanols or embed into the silica condensation network through coordination and hydrogen bonding, resulting in the inclusion of Si-O-P structural units in the sol-gel nuclei. Trimethyl borate hydrolyzes to form boric acid / boronic acid species in the aqueous environment, which can condense with silanols and enter the sol structure as glass network modifier units. The sealing and aging stage is dominated by condensation, and the sol-gel nuclei transition from small molecular clusters to higher connectivity inorganic networks, while the surface still maintains a certain density of reactive hydroxyl sites. The sol-gel nuclei are dispersed into the isomeric hydrocarbon phase and form an oil-in-water dispersion system under the action of Span 80. After the addition of shell monomer liquid, free radical polymerization occurs under the action of initiator. Methyl methacrylate provides the polymer backbone, glycidyl methacrylate provides epoxy functional groups as subsequent interfacial reaction sites, and ethylene glycol dimethacrylate provides crosslinking points to form a three-dimensional network shell.

[0016] In step S3, ethyl cellulose is dissolved in an ester solvent, and after cooling, poly(lauryl methacrylate) is added. The dispersant is compatible with the organic phase through its hydrophobic segment and interacts with the surface of inorganic particles through polar groups, thereby reducing the flocculation tendency of silver powder and glass powder in the organic phase. The mZrP-MA slurry and core-shell dispersion are added to the polymer carrier, and the mZrP-MA nanosheets form a sheet network through the solvation interaction of the surface organic silicon layer with the carrier solvent, and the core-shell particles provide additional inter-particle volume fraction effects and interfacial friction effects as discrete micro-phase fillers in the polymer solution, thereby affecting the thixotropic recovery and anti-settling behavior.

[0017] During subsequent printing, drying, and sintering processes, the organic carrier gradually volatilizes and undergoes thermal cracking, and the silver powder particles form necks at contact points and sinter to become densified; the glass powder transitions to a viscous liquid phase after reaching the softening and melting interval and migrates along the inter-particle gaps, and the liquid phase chemically interacts with the native oxide layer or the grooved exposed interface of the silicon surface, typical processes include rearrangement of the silicon-oxygen bond environment and formation of silicate / borosilicate interface layers, thereby establishing an electrical contact channel between the silver electrode and the silicon. The mZrP-MA nanosheets form a geometric barrier in the liquid phase migration path and increase the diffusion tortuosity; the core-shell dispersion relies on the cross-linked shell layer to maintain its shape during the drying stage, and the sol-gel nuclei are exposed after the shell layer thermally cracks upon heating, and the sol-gel nuclei further condense and convert to inorganic networks as the temperature rises, which enter the glass phase or are distributed near the interface, changing the structural connectivity and local fluidity of the glass phase, thereby restricting the spreading, penetration, and reaction range of the liquid phase.

[0018] As a preferred technical solution of the present application, in S1, the mass ratio of the zirconium oxychloride octahydrate, the deionized water and the phosphoric acid solution is (30-34):(300-340):(70-105), for example, it can be (30, 30.4, 30.8, 31.2, 31.6, 32.0, 32.4, 32.8, 33.2, 33.6 or 34):(300, 304, 308, 312, 316, 320, 324, 328, 332, 336 or 340):(70, 73.5, 77, 80.5, 84, 87.5, 91, 94.5, 98, 101.5 or 105), but is not limited to the listed values, and other values not listed in the range are also applicable.

[0019] In some optional embodiments, the first temperature is 80-85℃, for example, it can be 80℃, 80.5℃, 81℃, 81.5℃, 82℃, 82.5℃, 83℃, 83.5℃, 84℃, 84.5℃ or 85℃, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0020] In some optional embodiments, the mass fraction of the phosphoric acid solution is 15-20wt.%, for example, it can be 15wt.%, 15.5wt.%, 16wt.%, 16.5wt.%, 17wt.%, 17.5wt.%, 18wt.%, 18.5wt.%, 19wt.%, 19.5wt.% or 20wt.%, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0021] In some optional embodiments, the dropping time is 50-70min, for example, it can be 50min, 52min, 54min, 56min, 58min, 60min, 62min, 64min, 66min, 68min or 70min, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0022] In some optional embodiments, the second temperature is 88-92℃, for example, it can be 88℃, 88.4℃, 88.8℃, 89.2℃, 89.6℃, 90.0℃, 90.4℃, 90.8℃, 91.2℃, 91.6℃ or 92℃, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0023] In some optional embodiments, the aging time is 20-28 hours, for example, 20.0 hours, 20.8 hours, 21.6 hours, 22.4 hours, 23.2 hours, 24.0 hours, 24.8 hours, 25.6 hours, 26.4 hours, 27.2 hours, or 28.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0024] In some optional embodiments, the mass ratio of α-ZrP powder, anhydrous ethanol, n-butylamine, methacryloxypropyltrimethoxysilane, second deionized water, and glacial acetic acid is (9-11):(170-210):(10-14):(1.2-1.8):(0.8-1.2):(0.15-0.3), for example, it can be (9, 9.2, 9.4, 9.6, 9.8, 10.0, 10.2, 10.4, 10.6, 10.8, or 11):(170, 174, 178, 182, 186, 190, 194, 198, 202, 206, or 210):(10, 10.4, 10.8, 11.2,... 11.6, 12.0, 12.4, 12.8, 13.2, 13.6 or 14: (1.2, 1.26, 1.32, 1.38, 1.44, 1.5, 1.56, 1.62, 1.68, 1.74 or 1.8): (0.8, 0.84, 0.88, 0.92, 0.96, 1.0, 1.04, 1.08, 1.12, 1.16 or 1.2): (0.15, 0.165, 0.18, 0.195, 0.21, 0.225, 0.24, 0.255, 0.27, 0.285 or 0.3), but not limited to the listed values; other unlisted values ​​within this range also apply.

[0025] In some alternative embodiments, the third temperature is 35-45°C, for example, it can be 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, 41°C, 42°C, 43°C, 44°C or 45°C, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0026] In some optional embodiments, the stirring time at the third temperature is 10-14 hours, for example, 10.0 hours, 10.4 hours, 10.8 hours, 11.2 hours, 11.6 hours, 12.0 hours, 12.4 hours, 12.8 hours, 13.2 hours, 13.6 hours, or 14.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0027] In some optional embodiments, the mass ratio of the mZrP-MA dry powder to diethylene glycol butyl ether acetate is (8-10):(18-25), for example, it can be (8.0, 8.2, 8.4, 8.6, 8.8, 9.0, 9.2, 9.4, 9.6, 9.8 or 10.0):(18, 18.7, 19.4, 20.1, 20.8, 21.5, 22.2, 22.9, 23.6, 24.3 or 25), but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0028] In some optional embodiments, the solid content of the mZrP-MA slurry is 25-35 wt.%, for example, it can be 25 wt.%, 26 wt.%, 27 wt.%, 28 wt.%, 29 wt.%, 30 wt.%, 31 wt.%, 32 wt.%, 33 wt.%, 34 wt.%, or 35 wt.%, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0029] In some alternative embodiments, the fourth temperature is 50-60°C, for example, it can be 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C or 60°C, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0030] In some optional embodiments, the stirring reaction time at the fourth temperature is 3-5 hours, for example, 3 hours, 3.2 hours, 3.4 hours, 3.6 hours, 3.8 hours, 4.0 hours, 4.2 hours, 4.4 hours, 4.6 hours, 4.8 hours, or 5.0 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0031] As a preferred embodiment of the present invention, in S2, the mass ratio of diethylene glycol butyl ether acetate, tetraethyl orthosilicate, triethyl phosphate, trimethylborate, anhydrous ethanol, and aqueous acetic acid is (45-55):(9-11):(4-6):(2.5-3.5):(4-6):(1.2-1.8), for example, it can be (45, 46, 47, 48, 49, 50, 51, 52, 53, 54 or 55):(9, 9.2, 9.4, 9.6, 9.8, 10.0, 10.2, 10.4, 10.6, 10.8 or 11):(4, 4.2, 4.4, 4.6, 4.8, 5.0, 5.2, 5.4, 5.6, 5.8 or 6: (2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4 or 3.5): (4, 4.2, 4.4, 4.6, 4.8, 5.0, 5.2, 5.4, 5.6, 5.8 or 6): (1.2, 1.26, 1.32, 1.38, 1.44, 1.5, 1.56, 1.62, 1.68, 1.74 or 1.8), but not limited to the listed values; other unlisted values ​​within this range also apply.

[0032] In some optional embodiments, the mass fraction of the acetic acid aqueous solution is 12-27 wt.%, for example, it can be 12 wt.%, 13.5 wt.%, 15 wt.%, 16.5 wt.%, 18 wt.%, 19.5 wt.%, 21 wt.%, 22.5 wt.%, 24 wt.%, 25.5 wt.%, or 27 wt.%, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0033] In some optional embodiments, the continued stirring time is 1.5-2.5h, for example, it can be 1.5h, 1.6h, 1.7h, 1.8h, 1.9h, 2.0h, 2.1h, 2.2h, 2.3h, 2.4h or 2.5h, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0034] In some optional embodiments, the aging temperature is 20-30°C and the time is 10-14 hours. For example, the temperature can be (20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30)°C and the time can be (10.0, 10.4, 10.8, 11.2, 11.6, 12.0, 12.4, 12.8, 13.2, 13.6 or 14.0) hours, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0035] In some optional embodiments, the mass ratio of isododecane, Span 80, sol core, methyl methacrylate, glycidyl methacrylate, ethylene glycol dimethacrylate, and azobisisobutyronitrile is (200-240):(5-7):(65-75):(16-20):(1.5-2.5):(1.5-2.5):(0.3-0.5), for example, it can be (200, 204, 208, 212, 216, 220, 224, 228, 232, 236 or 240):(5.0, 5.2, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8 or 7.0):(65, 66, 67, 68, 69, 70, 71, 72, 73, 7 4 or 75): (16, 16.4, 16.8, 17.2, 17.6, 18.0, 18.4, 18.8, 19.2, 19.6 or 20): (1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4 or 2.5): (1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4 or 2.5): (0.3, 0.32, 0.34, 0.36, 0.38, 0.4, 0.42, 0.44, 0.46, 0.48 or 0.5), but not limited to the listed values; other unlisted values ​​within this range also apply.

[0036] In some alternative embodiments, the fifth temperature is 68-72°C, for example, it can be 68°C, 68.4°C, 68.8°C, 69.2°C, 69.6°C, 70.0°C, 70.4°C, 70.8°C, 71.2°C, 71.6°C, or 72°C, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0037] In some optional embodiments, the reaction time at the fifth temperature is 6-7 hours, for example, 6.0 hours, 6.1 hours, 6.2 hours, 6.3 hours, 6.4 hours, 6.5 hours, 6.6 hours, 6.7 hours, 6.8 hours, 6.9 hours, or 7.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0038] In some optional embodiments, the solid content of the dispersion is 25-35 wt.%, for example, it can be 25 wt.%, 26 wt.%, 27 wt.%, 28 wt.%, 29 wt.%, 30 wt.%, 31 wt.%, 32 wt.%, 33 wt.%, 34 wt.%, or 35 wt.%, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0039] As a preferred embodiment of the present invention, in S3, the mass ratio of ethyl cellulose, diethylene glycol butyl ether acetate, polymethyl methacrylate, mZrP-MA slurry, dispersion, glass powder, spherical silver powder, and tetrabutyl titanate is (12-25):(135-230):(3-10):(3-40):(6-40):(20-50):(700-800):(1-5), for example, it can be (12, 13.3, 14.6, 15.9, 17.2, 18.5, 19.8, 21.1, 22.4, 23.7 or 25):(135, 144.5, 154, 163.5, 173, 182.5, 192, 201.5, 211, 220.5 or 230):(3, 3.7, 4.4, 5.1, 5.8, 6.5). 7.2, 7.9, 8.6, 9.3 or 10: (3, 6.7, 10.4, 14.1, 17.8, 21.5, 25.2, 28.9, 32.6, 36.3 or 40): (6, 9.4, 12.8, 16.2, 19.6, 23, 26.4, 29.8, 33.2, 36.6 or 40): (20, 23, 26, 29, 32, 35, 38, 41, 44, 47 or 50: (700, 710, 720, 730, 740, 750, 760, 770, 780, 790 or 800): (1.0, 1.4, 1.8, 2.2, 2.6, 3.0, 3.4, 3.8, 4.2, 4.6 or 5.0), but not limited to the listed values, other unlisted values ​​within this range also apply.

[0040] In some optional embodiments, the degree of polymerization of the ethyl cellulose is 450.

[0041] In some optional embodiments, the glass powder is composed of the following molar percentage components: SiO2 35-45%, B2O3 15-25%, ZnO 10-20%, Li2O 5-10%, ZrO2 3-8%, Al2O3 2-5%. After mixing the components, the mixture is kept at 1200-1300℃ for 2-3 hours, water-quenched into glass blocks, ball-milled to a D50 of 1-3 μm, and dried at 120-130℃ for 2-3 hours. For example, it could be composed of the following molar percentages: SiO2 (35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, or 45%), B2O3 (15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, or 25%), and ZnO (10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, or 18%). 19% or 20% of Li₂O, (5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5% or 10%) of ZrO₂, (3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, 6.0%, 6.5%, 7.0%, 7.5% or 8.0%) of Al₂O₃, and (2.0%, 2.3%, 2.6%, 2.9%, 3.2%, 3.5%, 3.8%) of Al₂O₃. 4.1%, 4.4%, 4.7% or 5.0%, each component is mixed and then held at (1200, 1210, 1220, 1230, 1240, 1250, 1260, 1270, 1280, 1290 or 1300)℃ for (2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9 or 3.0) hours, water-quenched into glass blocks, and ball-milled to a D50 of (1.0, 1.2, 1.4, ...). Dry at (120, 121, 122, 123, 124, 125, 126, 127, 128, 129, or 130) °C for (2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0) h, but not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0042] In some optional embodiments, the spherical silver powder has a D50 of 1-2 μm and a tap density ≥4.0 g / cm³. 3 For example, it could have a D50 of (1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.0) μm and a tap density ≥ 4.0 g / cm³. 3 However, this does not apply to all values ​​listed; other unlisted values ​​within the same range also apply.

[0043] In some optional embodiments, the viscosity of the glass powder silver paste adapted for laser-grooved TOPCon cells is 30,000-40,000 mPa·s.

[0044] In a second aspect, the present invention provides a glass powder silver paste adapted for laser-grooved TOPCon cells, prepared by the preparation method described in the first aspect.

[0045] Thirdly, the present invention provides a glass powder silver paste adapted for laser-grooved TOPCon batteries, which is used in the preparation of electrodes in the laser-grooved area of ​​TOPCon batteries. After printing, the glass powder silver paste is dried in stages to remove volatile components, and then sintered in a nitrogen atmosphere at 650-700℃.

[0046] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention introduces surface-functionalized exfoliated zirconium phosphate nanosheet slurry and sol core / crosslinked shell core-shell dispersion into the glass powder silver paste, so that the organic carrier forms a stable dispersion system and maintains controllable rheology, reduces agglomeration and sedimentation, and improves the continuity and consistency of printed lines; during the drying stage, the core-shell structure provides transient support, inhibiting component stratification and cell enrichment caused by solvent migration; during the sintering stage, the nanosheet confinement inhibits the deep penetration of the glass phase, and the thermal conversion of the sol core generates an inorganic network that couples with the glass phase, synergistically regulating the flow, wetting and interfacial reaction range of the glass phase, reducing the risk of over-corrosion in the cell opening area and ensuring the formation of electrical contact. Detailed Implementation

[0047] The technical solution of the present invention will be described in detail below with reference to specific embodiments. The embodiments described herein are specific implementations of the present invention and are used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary and should not be construed as limiting the implementation of the present invention or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can also adopt other obvious technical solutions based on the content disclosed in the claims and the specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0048] The chemical reagents used in the embodiments and comparative examples of this invention are all commercially available products and have not undergone any further purification treatment.

[0049] Example 1

[0050] This embodiment provides a glass powder silver paste adapted for laser-grooved TOPCon cells and its preparation method. The preparation method specifically includes the following steps:

[0051] S1, 30g of zirconium oxychloride octahydrate was mixed with 340g of deionized water to obtain a zirconium salt solution. Under a nitrogen atmosphere, the temperature was raised to 80℃. 105g of 15wt.% phosphoric acid solution was added dropwise to the zirconium salt solution while stirring for 70min. Then, the temperature was raised to 88℃ and aged for 28h to obtain α-ZrP precipitate slurry. After centrifugation, washing, and drying, α-ZrP powder was obtained. 11g of α-ZrP powder, 170g of anhydrous ethanol, and 14g of n-butylamine were mixed and stirred at 45℃ for 10h to obtain an intercalation slurry. The intercalation slurry was sheared and dispersed to obtain a nanosheet dispersion. 1.8g of methacryloyloxypropyltrimethoxysilane, 0.8g of deionized water, and 0.30g of glacial acetic acid were mixed to obtain a pre-hydrolyzed solution. The pre-hydrolyzed solution was added to the nanosheet dispersion and stirred at 60℃ for 3h. After centrifugation, washing, and drying, mZrP-MA dry powder was obtained. 8g of... mZrP-MA dry powder was mixed and dispersed with 25g of diethylene glycol butyl ether acetate to obtain mZrP-MA slurry, wherein the solid content of the mZrP-MA slurry was 25wt.%.

[0052] S2, 55g of diethylene glycol butyl ether acetate, 9g of tetraethyl orthosilicate, 6g of triethyl phosphate, 2.5g of trimethylboronic acid ester, and 6g of anhydrous ethanol were mixed to obtain solution A. At room temperature, 1.2g of a 27wt.% aqueous acetic acid solution was added dropwise to solution A and stirring continued for 2.5h. The solution was then sealed and aged at 20℃ for 14h to obtain the sol core. 240g of isododecane and 5g of... Span80 was mixed and dispersed with 75g of sol core to obtain a W / O dispersion system. 20g of methyl methacrylate, 1.5g of glycidyl methacrylate, 2.5g of ethylene glycol dimethacrylate, and 0.30g of azobisisobutyronitrile were mixed to obtain a shell monomer liquid. This shell monomer liquid was added to the W / O dispersion system, and the mixture was reacted at 72°C for 6 hours under a nitrogen atmosphere to obtain a hydrocarbon phase dispersion. Diethylene glycol butyl ether acetate was added to the hydrocarbon phase dispersion, and after stirring and settling, the upper layer was discarded. Diethylene glycol butyl ether acetate was then added to the lower dispersed phase, and the mixture was stirred and settling. This process was repeated three times to obtain a dispersion with a solid content of 25 wt.%.

[0053] S3. 25g of ethyl cellulose with a degree of polymerization of 450 and 135g of diethylene glycol butyl ether acetate were mixed and homogenized at 72℃. After cooling, 3g of polymethyl methacrylate lauryl ester, 40g of 25wt.% mZrP-MA slurry, and 6g of 25wt.% dispersion were added sequentially to obtain an organic carrier. 50g of glass powder, 700g of spherical silver powder, and 1g of tetrabutyl titanate were mixed with the organic carrier. The glass powder consisted of the following molar percentages: SiO2 35%, B2O3 25%, ZnO 10%, Li2O 10%, ZrO2 3%, and Al2O3 2%. After mixing, the mixture was kept at 1300℃ for 2h, water-quenched to form glass blocks, ball-milled to a D50 of 3μm, and dried at 130℃ for 2h. The spherical silver powder had a D50 of 1μm and a tap density ≥4.0g / cm³. 3 Vacuum degassing and three-roll milling are used to obtain a glass powder silver paste suitable for laser-grooved TOPCon batteries. The viscosity of the glass powder silver paste suitable for laser-grooved TOPCon batteries is 30000 mPa·s.

[0054] Example 2

[0055] This embodiment provides a glass powder silver paste adapted for laser-grooved TOPCon cells and its preparation method. The preparation method specifically includes the following steps:

[0056] S1, 34g of zirconium oxychloride octahydrate was mixed with 300g of deionized water to obtain a zirconium salt solution. Under a nitrogen atmosphere, the temperature was raised to 85℃. 70g of 20wt.% phosphoric acid solution was added dropwise to the zirconium salt solution while stirring for 50min. Then, the temperature was raised to 92℃ and aged for 20h to obtain α-ZrP precipitate slurry. After centrifugation, washing, and drying, α-ZrP powder was obtained. 9g of α-ZrP powder, 210g of anhydrous ethanol, and 10g of n-butylamine were mixed and stirred at 35℃ for 14h to obtain an intercalation slurry. The intercalation slurry was sheared and dispersed to obtain a nanosheet dispersion. 1.2g of methacryloyloxypropyltrimethoxysilane, 1.2g of deionized water, and 0.15g of glacial acetic acid were mixed to obtain a pre-hydrolyzed solution. The pre-hydrolyzed solution was added to the nanosheet dispersion and stirred at 50℃ for 5h. After centrifugation, washing, and drying, mZrP-MA dry powder was obtained. 10g of... mZrP-MA dry powder was mixed and dispersed with 18g of diethylene glycol butyl ether acetate to obtain mZrP-MA slurry, wherein the solid content of the mZrP-MA slurry was 35 wt.%.

[0057] S2, 45g of diethylene glycol butyl ether acetate, 11g of tetraethyl orthosilicate, 4g of triethyl phosphate, 3.5g of trimethylboronic acid ester, and 4g of anhydrous ethanol were mixed to obtain solution A. At room temperature, 1.8g of a 12wt.% aqueous acetic acid solution was added dropwise to solution A and stirring was continued for 1.5h. The solution was then sealed and aged at 30℃ for 10h to obtain the sol core. 200g of isododecane and 7g of Span were then added... 80g of sol core and 65g of diethylene glycol dimethacrylate were mixed and dispersed to obtain a W / O dispersion system. 16g of methyl methacrylate, 2.5g of glycidyl methacrylate, 1.5g of ethylene glycol dimethacrylate, and 0.50g of azobisisobutyronitrile were mixed to obtain a shell monomer liquid. This shell monomer liquid was added to the W / O dispersion system, and the mixture was reacted at 68°C for 7 hours under a nitrogen atmosphere to obtain a hydrocarbon phase dispersion. Diethylene glycol butyl ether acetate was added to the hydrocarbon phase dispersion, and after stirring and settling, the upper layer was discarded. Diethylene glycol butyl ether acetate was then added to the lower dispersed phase, and the mixture was stirred and settling. This process was repeated twice to obtain a dispersion with a solid content of 35 wt.%.

[0058] S3. 12g of ethyl cellulose with a degree of polymerization of 450 and 230g of diethylene glycol butyl ether acetate were mixed and homogenized at 68℃. After cooling, 10g of polymethyl methacrylate lauryl ester, 3g of 35wt.% mZrP-MA slurry, and 40g of 35wt.% dispersion were added sequentially to obtain an organic carrier. 20g of glass powder, 800g of spherical silver powder, and 5g of tetrabutyl titanate were mixed with the organic carrier. The glass powder consisted of the following molar percentages: SiO2 45%, B2O3 15%, ZnO 20%, Li2O 5%, ZrO2 8%, and Al2O3 5%. After mixing, the mixture was kept at 1200℃ for 3h, water-quenched to form glass blocks, ball-milled to a D50 of 1μm, and dried at 120℃ for 3h. The spherical silver powder had a D50 of 2μm and a tap density ≥4.0g / cm³. 3 Vacuum degassing and three-roll milling are used to obtain a glass powder silver paste suitable for laser-grooved TOPCon batteries. The viscosity of the glass powder silver paste suitable for laser-grooved TOPCon batteries is 40000 mPa·s.

[0059] Example 3

[0060] This embodiment provides a glass powder silver paste adapted for laser-grooved TOPCon cells and its preparation method. The preparation method specifically includes the following steps:

[0061] S1, 32g of zirconium oxychloride octahydrate was mixed with 320g of deionized water to obtain a zirconium salt solution. Under a nitrogen atmosphere, the temperature was raised to 82℃. 85g of 18wt.% phosphoric acid solution was added dropwise to the zirconium salt solution while stirring for 60min. Then, the temperature was raised to 90℃ and aged for 24h to obtain α-ZrP precipitate slurry. After centrifugation, washing, and drying, α-ZrP powder was obtained. 10g of α-ZrP powder, 190g of anhydrous ethanol, and 12g of n-butylamine were mixed and stirred at 40℃ for 12h to obtain an intercalation slurry. The intercalation slurry was sheared and dispersed to obtain a nanosheet dispersion. 1.5g of methacryloyloxypropyltrimethoxysilane, 1.0g of deionized water, and 0.22g of glacial acetic acid were mixed to obtain a pre-hydrolyzed solution. The pre-hydrolyzed solution was added to the nanosheet dispersion and stirred at 55℃ for 4h. After centrifugation, washing, and drying, mZrP-MA dry powder was obtained. 9g of... mZrP-MA dry powder was mixed and dispersed with 22g of diethylene glycol butyl ether acetate to obtain mZrP-MA slurry, wherein the solid content of the mZrP-MA slurry was 30 wt.%.

[0062] S2, 50g of diethylene glycol butyl ether acetate, 10g of tetraethyl orthosilicate, 5g of triethyl phosphate, 3.0g of trimethylboronic acid ester, and 5g of anhydrous ethanol were mixed to obtain solution A. At room temperature, 1.5g of a 20wt.% aqueous acetic acid solution was added dropwise to solution A and stirring was continued for 2.0h. The solution was then sealed and aged at 25℃ for 12h to obtain the sol core. 220g of isododecane and 6g of Span... 80g of sol core and 70g of sol core were mixed and dispersed to obtain a W / O dispersion system. 18g of methyl methacrylate, 2.0g of glycidyl methacrylate, 2.0g of ethylene glycol dimethacrylate, and 0.40g of azobisisobutyronitrile were mixed to obtain a shell monomer liquid. This shell monomer liquid was added to the W / O dispersion system, and the mixture was reacted at 70°C for 6.5h under a nitrogen atmosphere to obtain a hydrocarbon phase dispersion. Diethylene glycol butyl ether acetate was added to the hydrocarbon phase dispersion, and after stirring and settling, the upper layer was discarded. Diethylene glycol butyl ether acetate was then added to the lower dispersed phase, and the mixture was stirred and settling. This process was repeated twice to obtain a dispersion with a solid content of 30 wt.%.

[0063] S3. 18g of ethyl cellulose with a degree of polymerization of 450 and 180g of diethylene glycol butyl ether acetate were mixed and homogenized at 70℃. After cooling, 6g of polymethyl methacrylate lauryl ester, 20g of 30wt.% mZrP-MA slurry, and 25g of 30wt.% dispersion were added sequentially to obtain an organic carrier. 35g of glass powder, 750g of spherical silver powder, and 3g of tetrabutyl titanate were mixed with the organic carrier. The glass powder consisted of the following molar percentages: SiO2 40%, B2O3 20%, ZnO 15%, Li2O 8%, ZrO2 6%, and Al2O3 4%. After mixing, the mixture was kept at 1250℃ for 2.5h, water-quenched to form a glass block, ball-milled to a D50 of 2μm, and dried at 125℃ for 2.5h. The spherical silver powder had a D50 of 1.5μm and a tap density ≥4.0g / cm³. 3 Vacuum degassing and three-roll milling are used to obtain a glass powder silver paste suitable for laser-grooved TOPCon batteries. The viscosity of the glass powder silver paste suitable for laser-grooved TOPCon batteries is 33000 mPa·s.

[0064] Example 4

[0065] This embodiment provides a glass powder silver paste adapted for laser-grooved TOPCon cells and its preparation method. The preparation method specifically includes the following steps:

[0066] S1, 33g of zirconium oxychloride octahydrate was mixed with 310g of deionized water to obtain a zirconium salt solution. Under a nitrogen atmosphere, the solution was heated to 84℃. 90g of a 16wt.% phosphoric acid solution was added dropwise to the zirconium salt solution while stirring for 55 minutes. The solution was then heated to 91℃ and aged for 22 hours to obtain an α-ZrP precipitate. After centrifugation, washing, and drying, α-ZrP powder was obtained. 10.5g of… α-ZrP powder, 200g anhydrous ethanol, and 11g n-butylamine were mixed and stirred at 42℃ for 11h to obtain an intercalation slurry. The intercalation slurry was sheared and dispersed to obtain a nanosheet dispersion. 1.6g methacryloxypropyltrimethoxysilane, 1.1g deionized water, and 0.25g glacial acetic acid were mixed to obtain a pre-hydrolyzed solution. The pre-hydrolyzed solution was added to the nanosheet dispersion, and the mixture was stirred at 58℃ for 4.5h. After centrifugation, washing, and drying, mZrP-MA dry powder was obtained. 9.5g of mZrP-MA dry powder was mixed and dispersed with 20g diethylene glycol butyl ether acetate to obtain an mZrP-MA slurry. The solid content of the mZrP-MA slurry was 32wt.%.

[0067] S2, 48g of diethylene glycol butyl ether acetate, 10.5g of tetraethyl orthosilicate, 5.5g of triethyl phosphate, 3.2g of trimethylboronic acid ester, and 5.5g of anhydrous ethanol were mixed to obtain solution A. At room temperature, 1.6g of a 25wt.% aqueous acetic acid solution was added dropwise to solution A and stirring continued for 2.2h. The solution was then sealed and aged at 28℃ for 11h to obtain the sol core. 210g of isododecane and 6.5g of Span... 80g of sol core and 68g of diethylene glycol dimethacrylate were mixed and dispersed to obtain a W / O dispersion system. 17g of methyl methacrylate, 2.2g of glycidyl methacrylate, 2.2g of ethylene glycol dimethacrylate, and 0.45g of azobisisobutyronitrile were mixed to obtain a shell monomer liquid. This shell monomer liquid was added to the W / O dispersion system, and the mixture was reacted at 69°C for 6.2h under a nitrogen atmosphere to obtain a hydrocarbon phase dispersion. Diethylene glycol butyl ether acetate was added to the hydrocarbon phase dispersion, and after stirring and settling, the upper layer was discarded. Diethylene glycol butyl ether acetate was then added to the lower dispersed phase, and the mixture was stirred and settling. This process was repeated three times to obtain a dispersion with a solid content of 32 wt.%.

[0068] S3. 20g of ethyl cellulose with a polymerization degree of 450 and 200g of diethylene glycol butyl ether acetate were mixed and homogenized at 71℃. After cooling, 8g of polymethyl methacrylate lauryl ester, 30g of 32wt.% mZrP-MA slurry, and 30g of 32wt.% dispersion were added sequentially to obtain an organic carrier. 40g of glass powder, 720g of spherical silver powder, and 4g of tetrabutyl titanate were mixed with the organic carrier. The glass powder consisted of the following molar percentages: SiO2 42%, B2O3 18%, ZnO 18%, Li2O 6%, ZrO2 7%, and Al2O3 3%. After mixing, the mixture was kept at 1280℃ for 2.2h, water-quenched to form a glass block, ball-milled to a D50 of 1.5μm, and dried at 128℃ for 2.2h. The spherical silver powder had a D50 of 1.8μm and a tap density ≥4.0g / cm³. 3 Vacuum degassing and three-roll milling were performed to obtain a glass powder silver paste suitable for laser-grooved TOPCon batteries. The viscosity of the glass powder silver paste suitable for laser-grooved TOPCon batteries was 37000 mPa·s.

[0069] Comparative Example 1

[0070] This comparative example provides a glass powder silver paste adapted for laser-grooved TOPCon cells and its preparation method. The difference between this example and Example 1 is that the mass of mZrP-MA paste and dispersion in S3 is 0, and lead-containing glass powder is used as a mass substitute for the glass powder. Other process parameters and operating conditions are exactly the same as in Example 1.

[0071] Comparative Example 2

[0072] This comparative example provides a glass powder silver paste adapted for laser-grooved TOPCon cells and its preparation method. The difference between this example and Example 1 is that the mass of mZrP-MA paste in S3 is 0, and the reduced mass of mZrP-MA paste is made up with an equal mass of diethylene glycol butyl ether acetate. Other process parameters and operating conditions are exactly the same as in Example 1.

[0073] Comparative Example 3

[0074] This comparative example provides a glass powder silver paste adapted for laser-grooved TOPCon cells and its preparation method. The difference between this example and Example 1 is that the mass of the dispersion in S3 is 0, and the reduced mass of the dispersion is made up with an equal mass of diethylene glycol butyl ether acetate. Other process parameters and operating conditions are exactly the same as in Example 1.

[0075] The complete melting temperature of glass powder was determined by differential scanning calorimetry: dried glass powder was placed in a crucible and heated according to a fixed heating program under a specified atmosphere. The heat flow curve was recorded, and the endothermic peak characteristic temperature at which the glass powder transitioned from softening to melting was taken as the complete melting temperature. The average value of parallel tests was taken.

[0076] The tunneling oxide layer corrosion depth was determined using a cross-sectional morphology and thickness comparison method: After printing and sintering the laser-grooved TOPCon sample, a cross-sectional sample was prepared from the area covered by the finger grid. The difference in tunneling oxide layer thickness before and after sintering was measured using SEM or TEM, and the average value was calculated from multiple points along the finger grid direction.

[0077] Contact resistance was determined using the transmission line method: parallel silver bars with different spacings were printed on test pieces of the same structure and sintered using the same process. The total resistance was measured using a four-probe / micro-ohmmeter and linearly fitted to calculate the contact resistance.

[0078] The open-circuit voltage and conversion efficiency of the battery were tested using an I-V test under a solar simulator: the battery cells were fixed with standardized fixtures and a temperature control platform, and the I-V curves were measured under specified irradiation and spectral matching conditions. The Voc and efficiency were obtained from the curves, and the consistency was evaluated by repeated tests.

[0079] Table 1. Test results of glass powder silver paste in Examples 1-4 and Comparative Examples 1-3

[0080]

[0081] As shown in Table 1, compared with Example 1, Comparative Example 1 showed a decrease in glass powder melting temperature, an increase in corrosion depth, an increase in contact resistance, an increase in open-circuit voltage, and a decrease in conversion efficiency; Comparative Example 2 showed a decrease in glass powder melting temperature, an increase in corrosion depth, an increase in contact resistance, a decrease in open-circuit voltage, and a decrease in conversion efficiency; and Comparative Example 3 showed a decrease in glass powder melting temperature, an increase in corrosion depth, an increase in contact resistance, an increase in open-circuit voltage, and a decrease in conversion efficiency.

[0082] This is because, in Comparative Example 1, the lead-containing glass powder softens earlier, and the liquid phase rapidly penetrates the groove and expands the reaction zone during the initial sintering stage, leading to excessive corrosion of the tunneling oxide layer. Simultaneously, the lack of mZrP-MA confinement and core-shell stability results in uncontrolled glass phase flow and distribution, uneven interfacial contact, increased contact resistance, and decreased Voc and efficiency. In Comparative Example 2, the removal of mZrP-MA eliminates the lamellar barrier, allowing the glass phase to penetrate deeper along the groove wall and expand the reaction range, deepening oxide layer corrosion. Although retaining the core-shell dispersion can suppress some stratification and participate in network formation during sintering, it provides insufficient constraint on liquid phase penetration, leading to increased contact resistance and decreased Voc and efficiency. In Comparative Example 3, the removal of the core-shell dispersion weakens the carrier support during the drying stage. Solvent migration and component stratification cause uneven distribution of the glass phase in the grooved area. mZrP-MA still provides some confinement, limiting the increase in corrosion, but interfacial connectivity and densification stability deteriorate, resulting in a slight increase in contact resistance and a decrease in efficiency.

[0083] Table 2. Test results of the glass powder silver paste prepared in Example 1 and Comparative Example 1 at different sintering temperatures.

[0084]

[0085] As shown in Table 2, the contact resistance, open-circuit voltage, and efficiency of Example 1 showed small changes at different sintering temperatures, indicating that it has stronger adaptability and stability to the sintering window. In contrast, the contact resistance of Comparative Example 1 deteriorated significantly with increasing temperature, and Voc and efficiency decreased simultaneously, reflecting uncontrolled glass phase reaction and infiltration, and increased interface damage. This proves that the present invention can achieve controllable contact formation over a wide temperature range.

[0086] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for preparing glass powder silver paste adapted for laser-grooved TOPCon solar cells, characterized in that, The preparation method includes: S1, zirconium oxychloride octahydrate is mixed with first deionized water to obtain zirconium salt solution, phosphoric acid solution is added to zirconium salt solution and stirred and aged, dried to obtain α-ZrP powder, α-ZrP powder, anhydrous ethanol and n-butylamine are mixed to obtain nanosheet dispersion, methacryloyloxypropyltrimethoxysilane, second deionized water and glacial acetic acid are mixed to obtain pre-hydrolyzed solution, pre-hydrolyzed solution is added to nanosheet dispersion to react and obtain mZrP-MA dry powder, mZrP-MA dry powder is mixed and dispersed with diethylene glycol butyl ether acetate to obtain mZrP-MA slurry; S2, diethylene glycol butyl ether acetate, tetraethyl orthosilicate, triethyl phosphate, trimethylborate and anhydrous ethanol are mixed to obtain solution A. An aqueous acetic acid solution is added dropwise to solution A and aged to obtain a sol core. Isododecane and Span 80 are mixed with the sol core and dispersed to obtain a W / O dispersion system. Methyl methacrylate, glycidyl methacrylate, ethylene glycol dimethacrylate and azobisisobutyronitrile are mixed to obtain a shell monomer liquid. The shell monomer liquid is added to the W / O dispersion system for reaction, and diethylene glycol butyl ether acetate is added and stirred and allowed to stand to obtain a dispersion. S3, Ethyl cellulose and diethylene glycol butyl ether acetate are mixed, and polymethyl methacrylate, mZrP-MA slurry and dispersion are added in sequence to obtain an organic carrier. Glass powder, spherical silver powder, tetrabutyl titanate are mixed with the organic carrier to obtain a glass powder silver paste adapted to laser-grooved TOPCon batteries. The glass powder is composed of the following molar percentage components: SiO2 35-45%, B2O3 15-25%, ZnO 10-20%, Li2O 5-10%, ZrO2 3-8%, Al2O3 2-5%. After mixing the components, the mixture is kept at 1200-1300℃ for 2-3 hours, water-quenched into glass blocks, ball-milled to a D50 of 1-3μm, and dried at 120-130℃ for 2-3 hours. The spherical silver powder has a D50 of 1-2 μm and a tap density ≥4.0 g / cm³. 3 .

2. The method for preparing glass powder silver paste adapted for laser-grooved TOPCon cells according to claim 1, characterized in that, In S1: The mass ratio of zirconium oxychloride octahydrate, first deionized water and phosphoric acid solution is (30-34):(300-340):(70-105).

3. The method for preparing glass powder silver paste adapted for laser-grooved TOPCon cells according to claim 1, characterized in that, In S1: The mass ratio of α-ZrP powder, anhydrous ethanol, n-butylamine, methacryloyloxypropyltrimethoxysilane, second deionized water and glacial acetic acid is (9-11):(170-210):(10-14):(1.2-1.8):(0.8-1.2):(0.15-0.3).

4. The method for preparing glass powder silver paste adapted for laser-grooved TOPCon cells according to claim 1, characterized in that, In S1: The mass ratio of the mZrP-MA dry powder to diethylene glycol butyl ether acetate is (8-10):(18-25). The solid content of the mZrP-MA slurry is 25-35 wt.%.

5. The method for preparing glass powder silver paste adapted for laser-grooved TOPCon cells according to claim 1, characterized in that, In S2: The mass ratio of diethylene glycol butyl ether acetate, tetraethyl orthosilicate, triethyl phosphate, trimethylborate, anhydrous ethanol and acetic acid aqueous solution is (45-55):(9-11):(4-6):(2.5-3.5):(4-6):(1.2-1.8).

6. The method for preparing glass powder silver paste adapted for laser-grooved TOPCon cells according to claim 1, characterized in that, In S2: The mass ratio of isododecane, Span 80, sol core, methyl methacrylate, glycidyl methacrylate, ethylene glycol dimethacrylate, and azobisisobutyronitrile is (200-240):(5-7):(65-75):(16-20):(1.5-2.5):(1.5-2.5):(0.3-0.5). The solid content of the dispersion is 25-35 wt.

7. The method for preparing glass powder silver paste adapted for laser-grooved TOPCon cells according to claim 1, characterized in that, In S3: The mass ratio of ethyl cellulose, diethylene glycol butyl ether acetate, polymethyl methacrylate lauryl ester, mZrP-MA slurry, dispersion, glass powder, spherical silver powder and tetrabutyl titanate is (12-25):(135-230):(3-10):(3-40):(6-40):(20-50):(700-800):(1-5).

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