Solar cell and preparation method thereof, laminated cell and photovoltaic module

Abstract

The invention relates to the technical field of photovoltaic modules, in particular to a solar cell and a preparation method thereof, a laminated cell and a photovoltaic module. The preparation method of the solar cell comprises the following steps: providing a cell intermediate; coating a conductive material on the surface of the battery intermediate; sintering and curing the conductive material to form a preformed grid line; and performing laser processing on the preformed grid line to prepare the solar cell. Wherein the conductive material comprises metal powder, glass powder, organic resin, zirconium phosphate, aluminum phosphate, titanium phosphate and cerium oxide; the metal powder comprises one or more of silver powder, nickel powder, copper powder, aluminum powder, tin powder, silver-coated copper powder and silver-coated nickel powder. According to the conductive material provided by the invention, the proportion and the type of each component are finely controlled, and the conductive material cooperates with the steps of sintering curing and laser treatment, so that the prepared electrode has excellent chemical stability, and the power loss caused by potential-induced degradation can be greatly reduced.

Description

Technical Field

[0001] This application relates to the field of photovoltaic module technology, specifically to solar cells and their preparation methods, tandem cells, and photovoltaic modules. Background Technology

[0002] Photovoltaic modules convert solar energy into electrical energy by absorbing sunlight. Potential-induced degradation (PID) refers to the phenomenon in which photovoltaic modules, under the influence of complex environments such as high voltage bias, high temperature and high humidity, experience ion migration, interface charge accumulation, or passivation layer damage during actual operation, leading to an irreversible decrease in the photoelectric conversion efficiency of the cells.

[0003] Electrodes play a positive role in homogenizing the internal electric field distribution of photovoltaic modules. Electrodes are generally obtained through coating, sintering, and laser processing of conductive materials. However, traditional electrode preparation methods are not compatible with conductive materials, resulting in insufficient interfacial contact between the electrode and the battery substrate. Under long-term high-voltage bias and humid and hot environments, they cannot effectively suppress the migration of harmful ions and the accumulation of interfacial charges, making it difficult to significantly improve the PID phenomenon of photovoltaic modules and limiting the service life of photovoltaic modules under complex operating conditions. Summary of the Invention

[0004] Based on this, this application provides solar cells and their preparation methods, tandem cells, and photovoltaic modules.

[0005] A first aspect of this application provides a method for preparing a solar cell, comprising the following steps:

[0006] Provide battery intermediates;

[0007] A conductive material is coated on the surface of the battery intermediate.

[0008] The conductive material is sintered and solidified to form a pre-formed grid line;

[0009] The preformed grid lines are laser-processed to prepare the solar cell.

[0010] The conductive material includes metal powder, glass powder, organic resin, zirconium phosphate, aluminum phosphate, titanium phosphate, and cerium oxide. The metal powder includes one or more of silver powder, nickel powder, copper powder, aluminum powder, tin powder, silver-coated copper powder, and silver-coated nickel powder.

[0011] In some embodiments, the conductive material comprises, by mass fraction, the following components: 70% to 80% of the metal powder, 7% to 12% of the glass powder, 2% to 10% of the organic resin, 0.1% to 0.75% of the zirconium phosphate, 0.1% to 0.75% of the aluminum phosphate, 0.1% to 0.5% of the titanium phosphate, 0.1% to 1% of the cerium oxide, and 1% to 5% of the solvent.

[0012] In some embodiments, the D50 particle size of the zirconium phosphate, the aluminum phosphate, and the titanium phosphate is each independently 50 nm to 5 μm.

[0013] In some embodiments, the D50 particle size of the cerium oxide is 30 nm to 80 nm.

[0014] In some embodiments, the glass powder comprises the following components, with a total mass fraction of 100%: 35%~48% PbO, 12%~18% SiO2, 12%~28% B2O3, 1%~8% Al2O3 and 5%~14% ZnO.

[0015] In some embodiments, the D50 particle size of the glass powder is 1 μm to 5 μm.

[0016] In some embodiments, the fineness of the conductive material is 3μm to 5μm.

[0017] In some embodiments, the step of laser processing the preformed gate line includes: scanning the preformed gate line with a pulsed laser and applying a bias voltage to the preformed gate line.

[0018] In some embodiments, the pulse width of the pulsed laser is 10ns to 100ns, the frequency of the pulsed laser is 20kHz to 200kHz, the power of the pulsed laser is 10W to 50W, and the spot diameter of the pulsed laser is 20μm to 100μm.

[0019] In some embodiments, the scanning speed of the scanning process is 100 mm / s to 500 mm / s.

[0020] In some embodiments, the bias applied to the preformed gate line is a reverse bias voltage, wherein the reverse bias voltage is 5V to 20V.

[0021] A second aspect of this application provides a solar cell prepared by any of the preparation methods described in the first aspect of this application.

[0022] A third aspect of this application provides a tandem solar cell, including a top cell and a bottom cell, wherein at least one of the top cell and the bottom cell is a solar cell as described in the second aspect of this application.

[0023] A fourth aspect of this application provides a photovoltaic module, comprising: at least one battery string, the battery string comprising the solar cells described in the second aspect of this application or the tandem cells described in the third aspect of this application.

[0024] The method for preparing solar cells provided in this application has at least the following beneficial effects:

[0025] The preparation method provided in this application involves coating a conductive material onto the surface of a battery intermediate, then sintering and solidifying the conductive material, followed by laser processing to obtain the corresponding electrode. In this process, the conductive material, with its specific mass fraction composition, particularly through the synergistic effect of a three-component metal phosphate layered compound of zirconium phosphate, aluminum phosphate, and titanium phosphate, and cerium oxide, can improve the chemical stability and conductive durability of the conductive material and the prepared electrode under high temperature and high humidity conditions. Simultaneously, it enhances the interfacial bonding strength between the conductive material and the battery intermediate, thereby improving the solar cell's resistance to potential-induced degradation.

[0026] Specifically, certain types of three-component metal phosphate layered compounds and cerium oxide can achieve uniform dispersion and intercalation in conductive material systems. The metal phosphate layered compounds formed by the combination of zirconium phosphate, aluminum phosphate, and titanium phosphate, with their layered crystal structure, can be uniformly dispersed in the slurry system during the sintering of conductive materials, forming a dense and continuous layered protective barrier at the electrode film layer and the electrode-cell intermediate interface. This lays the foundation for physical protection and ion barrier protection to improve the anti-PID performance of solar cells. Simultaneously, the aforementioned metal phosphate layered compounds can also provide a stable dispersion carrier for cerium oxide, effectively preventing the failure of active sites caused by cerium oxide agglomeration. Furthermore, cerium oxide dispersed between the layers of the metal phosphate layered compounds or on the surface of the metal phosphate layered compounds can supplement the protective barrier formed by the layered compounds, further capturing and fixing active metal ions, and precisely suppressing trace ions penetrating the barrier and localized interfacial reactions. Metal phosphate layered compounds and cerium oxide, through structural intercalation and functional synergy, and with the cooperation of other components, can construct a highly efficient anti-PID protection system from two dimensions: physical barrier and ion capture. This not only enhances the structural stability of the electrode and interface, but also improves the chemical stability and corrosion resistance of conductive materials under harsh working conditions, and significantly reduces ion migration and interface leakage current problems under high pressure, high temperature and high humidity environments.

[0027] Therefore, the solar cell preparation method provided in this application, by precisely controlling the proportion and type of each component in the conductive material and adapting it to the steps of sintering and solidification and laser treatment, enables the electrode formed to have excellent chemical stability, thereby improving the stability of the solar cell under harsh conditions of high pressure, high temperature and high humidity for long-term operation and significantly reducing the power loss caused by potential-induced decay. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a flowchart of the fabrication process of a solar cell provided in one embodiment of this application.

[0030] Figure 2 This is a schematic diagram of the structure of a battery intermediate provided in one embodiment of this application.

[0031] Figure 3 This is a schematic diagram of the structure of the solar cell provided in one embodiment of this application.

[0032] Explanation of reference numerals in the attached figures

[0033] 10. TOPCon cell intermediate; 100. N-type silicon substrate; 110. First surface; 120. Second surface; 200. First doped layer; 300. Alumina layer; 400. First antireflection layer; 500. Tunneling layer; 600. Doped polycrystalline silicon layer; 700. Second antireflection layer; 20. Solar cell; 800. Front electrode; 900. Back electrode. Detailed Implementation

[0034] The following detailed description, in conjunction with specific embodiments, provides a more complete and clear account of the solar cells and their fabrication methods, tandem cells, and photovoltaic modules of this application. This application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0035] In the accompanying drawings of this application, the thicknesses of layers, films, regions, substrates, etc., are exaggerated for clarity. Throughout the specification, the same reference numerals refer to the same elements. It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it may be directly on the other element or there may be intervening elements. Conversely, when an element is referred to as being "directly on" another element, there are no intervening elements.

[0036] In the field of solar cells, PID (Power Degradation Ingress) easily causes power loss during long-term operation, which is a key issue restricting their service stability. Traditional technologies often employ low-sodium solutions to suppress PID degradation; for example, reducing the sodium content in conductive materials. +Content, etc. Although the above-mentioned traditional technologies can reduce the performance degradation caused by the migration of active ions, they will significantly affect the photoelectric conversion efficiency of the battery, making it difficult to balance anti-PID durability and high conversion efficiency.

[0037] Based on this, see Figure 1 The first aspect of this application provides a method for preparing a solar cell, comprising the following steps:

[0038] S1: Provides battery intermediates.

[0039] S2: Coating the surface of the battery intermediate with conductive material.

[0040] S3: Sinter and solidify the conductive material to form a pre-formed grid line.

[0041] S4: Laser treatment is performed on the pre-formed grid lines to prepare solar cells.

[0042] The conductive materials include metal powder, glass powder, organic resin, zirconium phosphate, aluminum phosphate, titanium phosphate, and cerium oxide. The metal powders include one or more of the following: silver powder, nickel powder, copper powder, aluminum powder, tin powder, silver-coated copper powder, and silver-coated nickel powder.

[0043] The preparation method of this application involves coating a conductive material onto the surface of a battery intermediate, sintering and solidifying the conductive material, and then laser-processing it to obtain the corresponding electrode. Here, the conductive material, relying on the synergistic effect of a layered metal phosphate compound composed of zirconium phosphate, aluminum phosphate, and titanium phosphate, and cerium oxide, not only significantly improves the chemical stability and conductivity durability of the electrode prepared from the conductive material under high temperature and high humidity conditions, strengthens the interfacial bonding strength with the battery intermediate, reduces interfacial contact resistance, and effectively improves the anti-potential-induced degradation (PID) performance of the solar cell, but also simultaneously optimizes the conductive transport efficiency of the electrode, thereby improving the photoelectric conversion efficiency.

[0044] Specifically, specific types and mass fractions of layered metal phosphate compounds and cerium oxide can achieve uniform dispersion and intercalation in conductive material systems. The layered crystal structure of the layered metal phosphate compounds allows for uniform dispersion within the system during slurry sintering, forming a dense and continuous layered protective barrier at the electrode film layer and the electrode-cell interface. This provides physical protection and ion barrier against PID degradation and optimizes the structural density of the electrode film. Simultaneously, the layered compound provides a stable dispersion carrier for cerium oxide, effectively preventing active site failure and conduction pathway obstruction caused by cerium oxide agglomeration. Cerium oxide dispersed between or on the surface of the layered metal phosphate compounds provides supplementary protection to the layered barrier, precisely capturing and fixing trace amounts of active metal ions that penetrate the barrier, suppressing localized adverse reactions at the interface, and further blocking PID degradation paths. Furthermore, its excellent dispersibility synergistically optimizes the conductive network of the electrode, reducing carrier transport losses. Through structural integration and functional synergy, combined with the compatibility of other components in the slurry, the two components construct an efficient system from multiple dimensions, including physical barrier, ion capture, and conductivity optimization. This not only enhances the structural and chemical stability of the electrodes and interfaces but also improves the conductivity durability of the slurry under harsh operating conditions, significantly reducing ion migration, interface leakage current, and carrier loss under high pressure, high temperature, and high humidity environments.

[0045] Therefore, the conductive material of this application, through precise control of the ratio and type of each component, enables the electrode to be prepared to have excellent chemical stability, low contact resistance and high conductivity. This can effectively improve the long-term operational stability of solar cells under harsh conditions of high pressure, high temperature and high humidity, significantly reduce the power loss caused by PID attenuation, and significantly improve the photoelectric conversion efficiency of the cell by optimizing the electrode conductivity and interface transport characteristics, thus achieving a dual improvement in anti-PID performance and conversion efficiency.

[0046] In some of these examples, the conductive material comprises the following components by mass fraction: 70%–80% metal powder, 7%–12% glass powder, 2%–10% organic resin, 0.1%–0.75% zirconium phosphate, 0.1%–0.75% aluminum phosphate, 0.1%–0.5% titanium phosphate, 0.1%–1% cerium oxide, and 1%–5% solvent.

[0047] This application discovers that the use of zirconium phosphate, aluminum phosphate, and titanium phosphate in layered metal phosphate compounds, with their complementary layered structures and synergistic cation interactions, can synergistically enhance the density, ion blocking ability, and interfacial compatibility of the layered protective barrier, significantly improving the physical barrier effect against active metal ions. As an example, the mass fraction of zirconium phosphate includes, but is not limited to, 0.1%, 0.13%, 0.15%, 0.18%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, or 0.75%, or any two of the above values ​​as endpoints. As an example, the mass fraction of aluminum phosphate includes, but is not limited to, 0.1%, 0.13%, 0.15%, 0.18%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, or 0.75%, or any two of the above values ​​as endpoints. As an example, the mass fraction of titanium phosphate includes, but is not limited to, 0.1%, 0.13%, 0.14%, 0.15%, 0.18%, 0.2%, 0.22%, 0.25%, 0.3%, 0.4%, or 0.5%, or any two of the above point values ​​as endpoints.

[0048] In some of these examples, the D50 particle size of zirconium phosphate, aluminum phosphate, and titanium phosphate is independently 50 nm to 5 μm.

[0049] In this application, "D50 particle size" refers to the median particle size, also known as the median particle size. It represents the particle size that corresponds to 50% of the cumulative particle size distribution. As an example, the testing methods for "D50 particle size" include, but are not limited to, laser diffraction.

[0050] In some examples, the D50 particle size of cerium oxide is 30 nm to 80 nm. The synergistic particle size distribution between the metal phosphate layered compound and cerium oxide allows cerium oxide to be uniformly dispersed on the carrier surface and in the interlayer spaces of the metal phosphate layered compound, fully leveraging its ion-trapping activity and forming a highly efficient and complementary anti-PID protection system with the layered protective barrier. Furthermore, the "cerium oxide" mentioned in this application refers to cerium dioxide.

[0051] In some examples, the conductive material further includes, by mass fraction, the following components: 1% to 5% thixotropic agent and 3% to 6% dispersant. As an example, the conductive material includes, by mass fraction, the following components: 70% to 80% metal powder, 7% to 12% glass powder, 2% to 10% organic resin, 0.1% to 0.75% zirconium phosphate, 0.1% to 0.75% aluminum phosphate, 0.1% to 0.5% titanium phosphate, 0.1% to 1% cerium oxide, 1% to 5% solvent, 1% to 5% thixotropic agent, and 3% to 6% dispersant.

[0052] Dispersants and thixotropic agents are added at specific mass fractions to synergistically optimize the dispersion stability, rheological properties and film-forming properties of the slurry, ensuring uniform dispersion of each functional component and adaptability of the slurry to the sintering process, while taking into account both the density of the electrode structure and the interfacial bonding effect.

[0053] The following examples further illustrate the properties of metal powder, glass powder, organic resin, thixotropic agent, dispersant, and solvent in conductive materials.

[0054] In some examples, the metal powder includes one or more of silver powder, nickel powder, copper powder, aluminum powder, tin powder, silver-coated copper powder, and silver-coated nickel powder. Further, the D50 particle size of the metal powder is 0.8 μm to 1.5 μm. Metal powder within this particle size range is beneficial for constructing the conductive network in the resulting electrode, thereby improving the conductivity of the solar cell. Simultaneously, the metal powder can also provide a dispersion substrate for layered metal phosphate compounds and cerium oxide, allowing them to be uniformly distributed in the conductive network, thus fully leveraging the synergistic anti-PID effect while ensuring efficient carrier transport and improving photoelectric conversion efficiency. Even further, the metal powder is one or more of spherical silver powder, spherical nickel powder, and spherical copper powder with a D50 particle size of 0.8 μm to 1.5 μm. In this application, "spherical" refers to powder with a spherical or near-spherical morphology. "Spherical" metal powder has high sphericity and its structural morphology differs significantly from that of flake-shaped metal powder. This application discovers that the metal powder has a spherical morphology and high compatibility with layered metal phosphate compounds and cerium oxide. After sintering, solidification, and laser treatment, a stable structure with strong bonding and excellent ion blocking ability can be formed at the electrode interface. This effectively suppresses corrosive ion penetration and interfacial leakage current, thereby improving the anti-PID performance of the solar cell. As mentioned above, the mass fraction of the metal powder is 70% to 80%. As an example, the mass fraction of the metal powder includes, but is not limited to, 70%, 72%, 74%, 75%, 76%, 78%, or 80%, or any two of the above values ​​as endpoints.

[0055] In some of these examples, the glass powder comprises, by mass fraction, 35%–48% PbO, 12%–18% SiO2, 12%–28% B2O3, 1%–8% Al2O3, and 5%–14% ZnO, with a total mass fraction of 100%.

[0056] This application discovers that the glass powder selected is a Pb-Si-B-Al-Zn system glass powder. This system of glass powder can form a highly efficient synergy with components such as metal powder, layered metal phosphate compounds, and cerium oxide in conductive materials. This synergistically optimizes the interface contact between the electrode conductive network and the intermediate layer of the solar cell, improving photoelectric conversion performance. It also synergistically constructs a dense ion-barrier layer, strengthening the suppression effect on alkali metal ion migration, significantly enhancing the anti-PID performance of the solar cell, and balancing photoelectric conversion efficiency and long-term operational reliability. As mentioned above, the mass fraction of the glass powder can be selected from any value between 7% and 12%. As an example, the mass fraction of the glass powder includes, but is not limited to, 7%, 8%, 9%, 10%, 11%, or 12%, or any two of the above values ​​as endpoints within a range.

[0057] In some of these examples, the D50 particle size of the glass powder is 1 μm to 5 μm.

[0058] In some of these examples, the organic resin includes one or more of linear triblock copolymers, polyvinyl butyral, and cellulose acetate butyrate.

[0059] In this application, "linear triblock copolymer" refers to a block copolymer formed by three monomer segments with different structures connected in a linear series, with a linear molecular chain structure, unbranched and uncrosslinked, and each monomer segment being a continuous homopolymer segment. The organic resin is selected from one or more of linear triblock copolymers, polyvinyl butyral, and cellulose acetate butyrate, exhibiting good compatibility with components such as metal powder, glass powder, layered metal phosphate compounds, and cerium oxide. It can synergistically improve the dispersion uniformity and system stability of the components in the conductive material, and optimize electrode film formation and interfacial adhesion. As mentioned above, the mass fraction of the organic resin in the conductive material is 2% to 10%. As an example, the mass fraction of the organic resin includes, but is not limited to, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10%, or any two of the above values ​​as endpoints.

[0060] The type of thixotropic agent plays a crucial role in controlling the coatability and molding stability of conductive materials. In some examples, the thixotropic agent includes one or more of polyethylene wax and hydrogenated castor oil. Furthermore, the aforementioned thixotropic agent is compatible with the components in the conductive material. As mentioned earlier, the mass fraction of the thixotropic agent in the conductive material is 1% to 5%. As an example, the mass fraction of the thixotropic agent in the conductive material includes, but is not limited to, 1%, 2%, 3%, 4%, or 5%, or any two of the above values ​​as endpoints.

[0061] In some examples, the dispersant includes one or more of phosphate ester dispersants and polyvinylpyrrolidone. For example, the types of phosphate ester dispersants include, but are not limited to, one or more of dodecyl phosphate, octadecyl phosphate, and isooctyl phosphate. As previously stated, the mass fraction of the dispersant can be selected from any value between 3% and 6%. As an example, the mass fraction of the dispersant includes, but is not limited to, 3%, 4%, 5%, or 6%, or a range formed by any two of the above points as endpoints.

[0062] The type of solvent plays a crucial role in dispersing the components in a conductive material. In some examples, the solvent includes one or more of butyl ether, methyl ester, and acetate. As previously mentioned, the mass fraction of the solvent is 1% to 5%. As an example, the mass fraction of the solvent includes, but is not limited to, 1%, 2%, 3%, 4%, or 5%, or any two of the above values ​​as endpoints.

[0063] This application also provides a method for preparing the conductive material according to the first aspect of this application, comprising the following steps:

[0064] Conductive materials are prepared by mixing metal powder, glass powder, organic resin, zirconium phosphate, aluminum phosphate, titanium phosphate, cerium oxide, and solvent according to the specified mass fractions.

[0065] In some of these examples, the steps of mixing metal powder, glass powder, organic resin, zirconium phosphate, aluminum phosphate, titanium phosphate, cerium oxide, and solvent in mass fractions include:

[0066] S10: Prepare a mixture by mixing zirconium phosphate, aluminum phosphate, titanium phosphate and cerium oxide;

[0067] S20: The mixture is sheared and dispersed with metal powder and glass powder under an inert atmosphere to prepare an intermediate material;

[0068] S30: Organic resin and solvent are added to intermediate materials, and the materials are ground to prepare conductive materials.

[0069] As an example, in step S10, this application does not limit the mixing method; mixing methods such as stirring and grinding can be used. In step S20, the inert gas includes, but is not limited to, nitrogen and argon. In step S30, the fineness of the conductive material after grinding is 2μm to 5μm.

[0070] In this application, "fineness" is a quantitative indicator of the degree of dispersion of solid particles in a conductive material, specifically representing the size of the largest detectable solid particle or hard agglomerate in the conductive material under specified test conditions. Fineness can be measured using a scraper fineness gauge.

[0071] As an example, the conductive material includes a thixotropic agent and a dispersant, which can be added in step S30.

[0072] In some examples, in step S2, the method of coating the conductive material includes, but is not limited to, printing. Further examples include, the coating process parameters including, but are not limited to: a gate opening width of 20 μm to 30 μm, a film thickness of 10 μm to 15 μm, a squeegee pressure of 40 N to 50 N, and a printing speed of 400 mm / s to 600 mm / s.

[0073] In some examples, step S3, the step of sintering and solidifying the conductive material to form a pre-formed grid line, includes heating to 650℃~750℃ at a heating rate of 5℃ / s~15℃ / s and holding at that temperature for 15s~60s. This application has found that the heating rate, peak temperature, and holding time are coordinated to ensure that the conductive material is fully melted and solidified to form a pre-formed grid line with a uniform structure, while avoiding grid line deformation, cracking, and damage to the battery intermediates caused by excessively rapid heating or excessively high temperatures. As examples, the heating rate includes, but is not limited to, 5℃ / s, 8℃ / s, 10℃ / s, 12℃ / s, 14℃ / s, or 15℃ / s. The peak temperature includes, but is not limited to, 650℃, 660℃, 680℃, 700℃, 720℃, 730℃, or 750℃, or any two of the above values ​​as endpoints.

[0074] In some examples, step S4, the step of laser processing the preformed electrode includes: scanning the preformed gate line with a pulsed laser and applying a bias voltage to the preformed gate line.

[0075] Furthermore, the pulse width of the pulsed laser is 10ns~100ns, the frequency of the pulsed laser is 20kHz~200kHz, the power of the pulsed laser is 10W~50W, and the spot diameter of the pulsed laser is 20μm~100μm.

[0076] As a further example, the scanning speed of the scanning process is 100 mm / s to 500 mm / s. The bias voltage applied to the preformed gate lines is a reverse bias voltage, and the reverse bias voltage is 5V to 20V.

[0077] These specific pulsed laser parameters can optimize the interface between the electrode and the solar cell intermediate without damaging the intermediate material, reducing defects and porosity. They can synergistically improve structural stability with conductive materials and suppress interfacial corrosion and performance degradation under humid and hot environments. For example, the pulse width of the pulsed laser includes, but is not limited to, 10ns, 20ns, 30ns, 40ns, 50ns, 80ns, or 100ns. The power of the pulsed laser includes, but is not limited to, 10W, 20W, 30W, 40W, or 50W. The spot diameter of the laser treatment includes, but is not limited to, 20μm, 40μm, 60μm, 80μm, or 100μm. The scanning speed includes, but is not limited to, 100mm / s, 200mm / s, 300mm / s, 400mm / s, or 500mm / s. The reverse bias voltage includes, but is not limited to, 5V, 8V, 10V, 12V, 15V, 18V, or 30V.

[0078] This application discovers that during laser processing, the pulse width, frequency, spot diameter, and reverse bias voltage of the pulsed laser are suitable for the aforementioned metal powders. Within these ranges, all parameters exhibit good compatibility with various metal powders, and no process conflicts or processing failures occur due to different types of metal powders. However, the power of the pulsed laser and the scanning speed of the scanning process need to be adaptively adjusted according to the different types of metal powders to ensure that all types of metal powders can achieve sufficient densification, good interface bonding, and avoid overheating or oxidation, thereby obtaining stable and excellent electrode performance. For example, when the metal powder is silver powder, the laser power is 10W~30W, and the scanning speed is 200mm / s~500mm / s. For example, when the metal powder is nickel powder, the laser power is 35W~50W, and the scanning speed is 100mm / s~250mm / s. For example, when the metal powder is copper powder, the laser power is 30W~50W, and the scanning speed is 100mm / s~300mm / s. For example, the metal powder is aluminum powder, the laser power is 15W~40W, and the scanning speed is 150mm / s~400mm / s. For example, the metal powder is tin powder, the laser power is 5W~15W, and the scanning speed is 300mm / s~500mm / s. For example, the metal powder is silver-coated copper powder, the laser power is 20W~40W, and the scanning speed is 150mm / s~400mm / s. For example, the metal powder is silver-coated nickel powder, the laser power is 25W~45W, and the scanning speed is 120mm / s~350mm / s.

[0079] A second aspect of this application provides a solar cell prepared by the method described in the first aspect of this application. For example, the solar cell includes a cell intermediate and an electrode disposed on the surface of the cell intermediate. The electrode is prepared by sintering and solidifying a conductive material and then laser processing. Further, the solar cell includes a cell intermediate and a front electrode disposed on the surface of the cell intermediate. The front electrode is prepared by sintering and solidifying a conductive material and then laser processing.

[0080] Understandably, the front side of the solar cell is the light-receiving surface. For example, the electrode and / or the front electrode comprises, by mass parts, the following components: 70 to 80 parts of metal powder, 7 to 12 parts of glass powder, 2 to 10 parts of organic resin, 0.1 to 0.75 parts of zirconium phosphate, 0.1 to 0.75 parts of aluminum phosphate, 0.1 to 0.5 parts of titanium phosphate, and 0.1 to 1 part of cerium oxide.

[0081] In some examples, the battery intermediate is a TOPCon battery intermediate. The aforementioned conductive material or the electrode made of the conductive material can form a low-resistance, dense and stable ohmic contact with silicon. It is compatible with the passivation contact structure of TOPCon batteries, does not damage the passivation performance of its tunneling oxide layer and polycrystalline silicon layer, and at the same time can enhance the interface's resistance to ion migration, so that the solar cell has both good anti-PID performance and good photoelectric conversion efficiency.

[0082] As an example, see Figure 2 The TOPCon cell intermediate 10 includes: an N-type silicon substrate 100 having a first surface 110 and a second surface 120 disposed opposite to each other. A first doped layer 200, an aluminum oxide layer 300, and a first antireflection layer 400 are sequentially disposed on the first surface 110. A tunneling layer 500, a doped polycrystalline silicon layer 600, and a second antireflection layer 700 are sequentially disposed on the second surface 120. Using the fabrication method provided in the first aspect of this application, a front electrode and a back electrode are formed on the TOPCon cell intermediate 10, and a schematic diagram of the structure of the resulting solar cell 20 is shown below. Figure 3 As shown. Figure 3 In the first antireflection layer 400, the front electrode 800 is disposed on the surface of the first antireflection layer 400 facing away from the alumina layer 300. The back electrode 900 is disposed on the surface of the second antireflection layer 700 facing away from the doped polysilicon layer 600.

[0083] A third aspect of this application provides a tandem solar cell. The tandem solar cell includes a top cell and a bottom cell. At least one of the top cell and the bottom cell is a solar cell as described in the second aspect of this application. Further, the cell intermediate is a TOPCon cell intermediate, which serves as the bottom cell in the tandem solar cell. Further, the top cell can be a perovskite solar cell. As an example, a perovskite solar cell includes: a first transport layer, a perovskite substrate, a second transport layer, a transparent conductive layer, and an antireflection layer stacked together. The first transport layer is directly opposite the bottom cell. The first transport layer can be either an electron transport layer or a hole transport layer, and the second transport layer can be either an electron transport layer or a hole transport layer.

[0084] A fourth aspect of this application provides a photovoltaic module, comprising: at least one cell string, the cell string including solar cells or tandem cells as described in the third aspect of this application. Further, the photovoltaic module further includes: an encapsulating film for covering the surface of the cell string; and a cover plate for covering the surface of the encapsulating film facing away from the cell string.

[0085] Photovoltaic modules, including the aforementioned solar cells, have high anti-PID performance and high photoelectric conversion efficiency. They can effectively suppress performance degradation under complex operating conditions, which is beneficial to improving the long-term operational stability of photovoltaic modules.

[0086] The following detailed embodiments illustrate this application in more detail. It should also be understood that the following embodiments are for further explanation only and should not be construed as limiting the scope of protection of this application. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of this application fall within the scope of protection of this application. The specific process parameters, etc., in the following embodiments are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the range based on the description herein, and are not necessarily limited to the specific values ​​in the embodiments below.

[0087] Example 1

[0088] Conductive material: comprising the following components by mass fraction: 75% metal powder, 10% glass powder, 4% organic resin, 0.8% metal phosphate layered compound, 0.2% cerium oxide, 3% thixotropic agent, 4% dispersant and 3% solvent. The metal powder is spherical silver powder with a D50 particle size of 1 μm; the glass powder is Pb-Si-B-Al-Zn glass powder with a D50 particle size of 3 μm, comprising the following components by mass fraction: 42% PbO, 17% SiO2, 22% B2O3, 7% Al2O3 and 12% ZnO; the organic resin is polyvinyl butyral; the metal phosphate layered compound comprises 0.3% zirconium phosphate, 0.3% aluminum phosphate and 0.2% titanium phosphate by mass fraction; the D50 particle size of zirconium phosphate is 1 μm; the D50 particle size of aluminum phosphate is 1 μm; the D50 particle size of titanium phosphate is 1 μm; the cerium oxide is cerium dioxide with a D50 particle size of 50 nm; the thixotropic agent is polyethylene wax; the dispersant is polyvinylpyrrolidone; and the solvent is diethylene glycol butyl ether acetate.

[0089] Preparation of conductive materials:

[0090] A metal phosphate layered compound and cerium oxide were mixed, and then silver powder and glass powder were added and sheared and dispersed under nitrogen to prepare an intermediate material. Organic resin, thixotropic agent, dispersant and solvent were added to the intermediate material, and then the mixture was ground to prepare a conductive material.

[0091] Fabrication of solar cells:

[0092] The above conductive material was used as the fine grid paste to fabricate a fine grid on the front side of the N-type TOPCon battery intermediate. The fine grid opening width was 25 μm, the film thickness was 12 μm, the scraper pressure was 45 N, and the printing speed was 500 mm / s. After printing, the pre-formed grid lines were sintered and cured at 700 °C in a chain sintering furnace to obtain pre-formed grid lines. A pulsed laser was used to scan the pre-formed grid lines, and a bias voltage was applied to the pre-formed grid lines to fabricate electrodes. The pulse width of the pulsed laser was 50 ns, the frequency was 100 kHz, the power was 30 W, the spot diameter was 50 μm, the scanning speed was 200 mm / s, and the bias voltage applied to the pre-formed grid lines was a reverse bias voltage of 10 V.

[0093] Example 2

[0094] Example 2 is essentially the same as Example 1, the main difference being that this example uses 0.1% zirconium phosphate, 0.5% aluminum phosphate, and 0.2% titanium phosphate as a layered metal phosphate compound. The D50 particle size of zirconium phosphate is 1 μm; the D50 particle size of aluminum phosphate is 1 μm; and the D50 particle size of titanium phosphate is 1 μm.

[0095] Example 3

[0096] Example 3 is basically the same as Example 1, the main difference being that this example uses zirconium phosphate (0.6% by mass), aluminum phosphate (0.6% by mass), and titanium phosphate (0.4% by mass) as a metal phosphate layered compound, and the mass fraction of the metal powder is changed to 74.2%. The D50 particle size of zirconium phosphate is 1 μm; the D50 particle size of aluminum phosphate is 1 μm; and the D50 particle size of titanium phosphate is 1 μm.

[0097] Example 4

[0098] Example 4 is basically the same as Example 1, the main difference being that this example uses Pb-Si-B system glass powder. The Pb-Si-B system glass powder includes the following components by mass fraction: 50% PbO, 7% SiO2, 5% B2O3, 5% Al2O3, 30% BaO and 3% Bi2O3.

[0099] Example 5

[0100] Example 5 is basically the same as Example 1, the main difference being that cellulose acetate butyrate is used as the organic resin in this example.

[0101] Example 6

[0102] Example 6 is basically the same as Example 1, the main difference being that hydrogenated castor oil is used as a thixotropic agent in this example.

[0103] Example 7

[0104] Example 7 is basically the same as Example 1, the main difference being that lauryl alcohol polyoxyethylene ether phosphate is used as a dispersant in this example.

[0105] Example 8

[0106] Example 8 is basically the same as Example 1, the main difference being that the conductive material in this example includes the following components by mass fraction: 70% metal powder, 10% glass powder, 8% organic resin, 0.8% metal phosphate layered compound, 0.2% cerium oxide, 4% thixotropic agent, 5% dispersant and 2% solvent. The metal powder is spherical silver powder with a D50 particle size of 1 μm; the glass powder is Pb-Si-B-Al-Zn glass powder with a D50 particle size of 3 μm, comprising the following components by mass fraction: 42% PbO, 17% SiO2, 22% B2O3, 7% Al2O3 and 12% ZnO; the organic resin is polyvinyl butyral; the metal phosphate layered compound comprises 0.3% zirconium phosphate, 0.3% aluminum phosphate and 0.2% titanium phosphate by mass fraction; the D50 particle size of zirconium phosphate is 1 μm; the D50 particle size of aluminum phosphate is 1 μm; the D50 particle size of titanium phosphate is 1 μm; the cerium oxide is cerium dioxide with a D50 particle size of 50 nm; the thixotropic agent is polyethylene wax; the dispersant is polyvinylpyrrolidone; and the solvent is diethylene glycol butyl ether acetate.

[0107] Example 9

[0108] Example 9 is basically the same as Example 1, the main difference being that the conductive material in this example includes the following components by mass fraction: 80% metal powder, 7% glass powder, 3% organic resin, 0.8% metal phosphate layered compound, 0.2% cerium oxide, 1% thixotropic agent, 3% dispersant and 5% solvent. The metal powder is spherical silver powder with a D50 particle size of 1 μm; the glass powder is Pb-Si-B-Al-Zn glass powder with a D50 particle size of 3 μm, comprising the following components by mass fraction: 42% PbO, 17% SiO2, 22% B2O3, 7% Al2O3 and 12% ZnO; the organic resin is polyvinyl butyral; the metal phosphate layered compound comprises 0.3% zirconium phosphate, 0.3% aluminum phosphate and 0.2% titanium phosphate by mass fraction; the D50 particle size of zirconium phosphate is 1 μm; the D50 particle size of aluminum phosphate is 1 μm; the D50 particle size of titanium phosphate is 1 μm; the cerium oxide is cerium dioxide with a D50 particle size of 50 nm; the thixotropic agent is polyethylene wax; the dispersant is polyvinylpyrrolidone; and the solvent is diethylene glycol butyl ether acetate.

[0109] Comparative Example 1

[0110] Comparative Example 1 is basically the same as Example 1, except that the conductive material in Comparative Example 1 does not include metal phosphate layered compounds and cerium oxide, and the mass fraction of metal powder in Comparative Example 1 is 76%.

[0111] Comparative Example 2

[0112] Comparative Example 2 is basically the same as Example 1, except that the conductive material in Comparative Example 2 does not include metal phosphate layered compounds, and the mass fraction of cerium oxide in Comparative Example 2 is 1%.

[0113] Comparative Example 3

[0114] Comparative Example 3 is basically the same as Example 1, the main difference being that the conductive material in Comparative Example 3 does not include cerium oxide, and the mass fraction of the metal phosphate layered compound is 1%. The metal phosphate layered compound in Comparative Example 3 is zirconium phosphate with a D50 particle size of 1 μm.

[0115] Comparative Example 4

[0116] Comparative Example 4 is essentially the same as Example 1, the main difference being the mass fraction of each component in the conductive material of Comparative Example 4, which differs from that of Example 1. The conductive material of Comparative Example 4 comprises the following components by mass fraction: 90% metal powder, 2% glass powder, 2% organic resin, 3% thixotropic agent, 2% dispersant, and 1% solvent. The metal powder is spherical silver powder with a D50 particle size of 1 μm; the glass powder is Pb-Si-B-Al-Zn glass powder with a D50 particle size of 3 μm, comprising the following components by mass fraction: 42% PbO, 17% SiO2, 22% B2O3, 7% Al2O3, and 12% ZnO; the organic resin is polyvinyl butyral; the thixotropic agent is polyethylene wax; the dispersant is polyvinylpyrrolidone; and the solvent is diethylene glycol butyl ether acetate.

[0117] Comparative Example 5

[0118] Conductive materials:

[0119] The conductive material comprises the following components by mass fraction: 70% metal powder, 12% glass powder, 8% organic resin, 1.5% metal phosphate layered compound, 0.7% cerium oxide, 2% thixotropic agent, 3% dispersant, and 2.8% solvent. The metal powder is spherical silver powder with a D50 particle size of 1 μm; the glass powder is Pb-Si-B-Al-Zn based glass powder with a D50 particle size of 3 μm, comprising the following components by mass fraction: 42% PbO, 17% SiO2, 22% B2O3, 7% Al2O3, and 12% ZnO; the organic resin is polyvinyl butyral; the metal phosphate layered compound is zirconium phosphate with a D50 particle size of 1 μm; the cerium oxide is cerium dioxide with a D50 particle size of 50 nm; the thixotropic agent is polyethylene wax; the dispersant is polyvinylpyrrolidone; and the solvent is diethylene glycol butyl ether acetate.

[0120] Preparation of conductive materials:

[0121] A metal phosphate layered compound and cerium oxide were mixed, and then silver powder and glass powder were added and sheared and dispersed under nitrogen to prepare an intermediate material. Organic resin, thixotropic agent, dispersant and solvent were added to the intermediate material, and then the mixture was ground to prepare a conductive material.

[0122] Preparation of solar cells: Same as in Example 1.

[0123] Comparative Example 6

[0124] Comparative Example 6 is essentially the same as Comparative Example 5, the main difference being that the mass fraction of each component of the conductive material in Comparative Example 6 differs from that in Comparative Example 5. The conductive material in this comparative example comprises the following components by mass fraction: 75% metal powder, 10% glass powder, 4% organic resin, 0.8% metal phosphate layered compound, 0.2% cerium oxide, 3% thixotropic agent, 4% dispersant, and 3% solvent. The metal powder is spherical silver powder with a D50 particle size of 1 μm; the glass powder is Pb-Si-B-Al-Zn glass powder with a D50 particle size of 3 μm, and the glass powder includes the following components by mass fraction: 42% PbO, 17% SiO2, 22% B2O3, 7% Al2O3 and 12% ZnO; the organic resin is polyvinyl butyral; the metal phosphate layered compound is zirconium phosphate with a D50 particle size of 1 μm; the cerium oxide is cerium dioxide with a D50 particle size of 50 nm; the thixotropic agent is polyethylene wax; the dispersant is polyvinylpyrrolidone; and the solvent is diethylene glycol butyl ether acetate.

[0125] Comparative Example 7

[0126] Comparative Example 7 is basically the same as Comparative Example 5, the main difference being that the mass fraction of each component of the conductive material in this comparative example is different from that in Comparative Example 5. The conductive material in this comparative example includes the following components by mass fraction: 80% metal powder, 7% glass powder, 2% organic resin, 0.5% metal phosphate layered compound, 0.1% cerium oxide, 5% thixotropic agent, 4% dispersant, and 1.4% solvent. The metal powder is spherical silver powder with a D50 particle size of 1 μm; the glass powder is Pb-Si-B-Al-Zn glass powder with a D50 particle size of 3 μm, and the glass powder includes the following components by mass fraction: 42% PbO, 17% SiO2, 22% B2O3, 7% Al2O3 and 12% ZnO; the organic resin is polyvinyl butyral; the metal phosphate layered compound is zirconium phosphate with a D50 particle size of 1 μm; the cerium oxide is cerium dioxide with a D50 particle size of 50 nm; the thixotropic agent is polyethylene wax; the dispersant is polyvinylpyrrolidone; and the solvent is diethylene glycol butyl ether acetate.

[0127] Comparative Example 8

[0128] Comparative Example 8 is essentially the same as Example 1, the main difference being that it uses 0.6% zirconium phosphate and 0.2% titanium phosphate by mass as a layered metal phosphate compound. The D50 particle size of zirconium phosphate is 1 μm; the D50 particle size of titanium phosphate is 1 μm.

[0129] Comparative Example 9

[0130] Comparative Example 9 is essentially the same as Example 1, the main difference being that it uses aluminum phosphate (0.6% by mass) and titanium phosphate (0.2% by mass) as a layered metal phosphate compound. The D50 particle size of aluminum phosphate is 1 μm; the D50 particle size of titanium phosphate is 1 μm.

[0131] The composition of the conductive materials in the above embodiments and comparative examples is shown in Tables 1 and 2.

[0132] Table 1

[0133]

[0134] Table 2

[0135]

[0136] Photovoltaic conversion efficiency: The solar cells prepared in the above examples and comparative examples were tested under standard test conditions (AM1.5, 25C, 1000W / m²). 2 ), to test photoelectric conversion efficiency.

[0137] PID testing: PID testing was conducted for 192 hours at 85% humidity, 85℃, and a system bias of -1000V, and the attenuation rate was recorded. The corresponding test results are shown in Table 3.

[0138] Table 3

[0139]

[0140] Comparing the test results of Examples 1-9 and Comparative Examples 1-9, it can be seen that Comparative Example 1 did not include either a metal phosphate layered compound or cerium oxide; Comparative Example 2 did not include a metal phosphate layered compound; Comparative Example 3 did not include cerium oxide; and the composition of Comparative Example 4 was unreasonable, and it was incompatible with the sintering, curing, and laser treatment steps of the conductive material of this application, thus failing to achieve a dual improvement in anti-PID performance and photoelectric conversion efficiency. Comparative Examples 5-7 used only a single metal phosphate layered compound, and Comparative Examples 8-9 used a combination of two metal phosphate layered compounds, and their anti-PID performance was also weaker than that of Examples 1-9. In Examples 1 to 9 of this application, the various components of the conductive material, the three-component metal phosphate layered compound, and the synergistic effect of cerium oxide, along with the sintering, curing, and laser treatment steps of the conductive material, enable the electrode to have good chemical stability and low contact resistance and high conductivity between the electrode and the battery intermediate. This results in the solar cell having both good photoelectric conversion efficiency and high anti-PID performance.

[0141] Examples 1, 2, 6, 8, and 9 are essentially the same, with the main difference being that Examples 1 and 2 use zirconium phosphate, aluminum phosphate, and titanium phosphate as a three-component composite metal phosphate layered compound, Comparative Example 6 uses a single-component metal phosphate layered compound, Comparative Example 8 uses zirconium phosphate and titanium phosphate as a two-component composite metal phosphate layered compound, and Comparative Example 9 uses aluminum phosphate and titanium phosphate as a two-component composite metal phosphate layered compound. As can be seen from the comparison of Examples 1, 2, 6, 8, and 9, Examples 1 and 2 use a three-component composite metal acid salt layered compound, which, in conjunction with the sintering, curing, and laser treatment processes, enables more sufficient interfacial contact between the electrode and the battery substrate. This effectively suppresses the migration of harmful ions and the accumulation of interfacial charge under long-term high-voltage bias and humid heat environments, resulting in improved anti-PID performance of the solar cells compared to Comparative Examples 6, 8, and 9.

[0142] Examples 1 and 3 are essentially the same, the main difference being the different mass fractions of the three-component compounded metal acid salt layered compound. A comparison of Examples 1 and 3 shows that both improve the anti-PID performance of the solar cell compared to Comparative Example 6. This indicates that the three-component compounded metal acid salt layered compound of this application is suitable for sintering, curing, and laser processing steps. The two components work synergistically to construct a stable interface structure with strong ion-blocking capabilities at the interface between the battery electrode and the battery intermediate, effectively suppressing the penetration of corrosive ions and the generation of interface leakage current, thereby improving the anti-PID performance.

[0143] Examples 1 and 4 are essentially the same, the main difference being the different glass powders used. As can be seen from the comparison, the Pb-Si-B-Al-Zn glass powder used in Example 1, in synergy with the three-component composite metal acid salt layered compound and the sintering and laser treatment processes, is more conducive to improving the anti-PID performance of solar cells. Therefore, it can be inferred that the specific composition of the Pb-Si-B-Al-Zn glass powder can form a better interfacial bonding state and phase structure with the three-component composite metal acid salt layered compound during sintering and solidification. Simultaneously, it effectively controls the interfacial stress and component distribution during subsequent laser treatment, thereby constructing a denser, more stable interfacial layer with stronger ion-blocking capabilities, ultimately improving the anti-PID performance of solar cells.

[0144] Examples 1 and 5 are essentially the same, the main difference being the different organic resins used. Examples 1 and 6 are essentially the same, the main difference being the different types of thixotropic agents used. Examples 1 and 7 are essentially the same, the main difference being the different types of dispersants used. Comparison revealed that the type of organic resin, thixotropic agent, and dispersant also slightly affects the anti-PID performance of the solar cell. Therefore, while the selection of organic resin, thixotropic agent, and dispersant in the conductive material has a less significant impact on the anti-PID performance of the battery than the synergistic effect of glass powder and the three-component compounded metal acid salt layered compound, it can still fine-tune the density and stability of the final interface layer by controlling the rheological properties, printability, and interfacial compatibility of the slurry, thus affecting the anti-PID performance of the battery to some extent.

[0145] Examples 1, 8, and 9 are essentially the same, with the main difference being the content of each component. A comparison of Examples 1, 8, and 9 shows that within the component range provided in this application, all components can improve the anti-PID performance of solar cells. This indicates that the conductive material provided in this application has good component compatibility with sintering, curing, and laser processing processes. With the adjustability of each component in the conductive material of this application, its combination with sintering, curing, and laser processing processes can achieve stable interfacial film formation and ion blocking effects, ensuring a reliable improvement in the anti-PID performance of solar cells.

[0146] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0147] The embodiments described above are merely illustrative of several implementation methods of this application, intended to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. It should be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. A method for preparing a solar cell, characterized in that, Includes the following steps: Provide battery intermediates; A conductive material is coated on the surface of the battery intermediate. The conductive material is sintered and solidified to form a pre-formed grid line; The preformed grid lines are laser-processed to fabricate the solar cell; The conductive material includes metal powder, glass powder, organic resin, zirconium phosphate, aluminum phosphate, titanium phosphate, and cerium oxide. The metal powder includes one or more of the following: silver powder, nickel powder, copper powder, aluminum powder, tin powder, silver-coated copper powder, and silver-coated nickel powder.

2. The method for preparing a solar cell according to claim 1, characterized in that, The conductive material comprises the following components by mass fraction: 70% to 80% of the metal powder, 7% to 12% of the glass powder, 2% to 10% of the organic resin, 0.1% to 0.75% of the zirconium phosphate, 0.1% to 0.75% of the aluminum phosphate, 0.1% to 0.5% of the titanium phosphate, 0.1% to 1% of the cerium oxide, and 1% to 5% of the solvent.

3. The method for preparing a solar cell according to claim 1, characterized in that, The D50 particle size of the zirconium phosphate, the aluminum phosphate, and the titanium phosphate is independently 50 nm to 5 μm.

4. The method for preparing a solar cell according to claim 1, characterized in that, The D50 particle size of the cerium oxide is 30nm~80nm.

5. The method for preparing a solar cell according to claim 1, characterized in that, Based on a total mass fraction of 100%, the glass powder comprises the following components: 35%~48% PbO, 12%~18% SiO2, 12%~28% B2O3, 1%~8% Al2O3 and 5%~14% ZnO.

6. The method for preparing a solar cell according to claim 5, characterized in that, The D50 particle size of the glass powder is 1μm~5μm.

7. The method for preparing a solar cell according to any one of claims 1 to 6, characterized in that, The fineness of the conductive material is 3μm~5μm.

8. The method for preparing a solar cell according to any one of claims 1 to 6, characterized in that, The step of sintering and solidifying the conductive material to form a preformed grid line includes: heating to 650℃~750℃ at a heating rate of 5℃ / s~15℃ / s and holding at that temperature for 15s~60s.

9. The method for preparing a solar cell according to any one of claims 1 to 6, characterized in that, The step of laser processing the preformed gate line includes: scanning the preformed gate line with a pulsed laser and applying a bias voltage to the preformed gate line.

10. The method for preparing a solar cell according to claim 9, characterized in that, The pulse width of the pulsed laser is 10ns to 100ns, the frequency of the pulsed laser is 20kHz to 200kHz, the power of the pulsed laser is 10W to 50W, and the spot diameter of the pulsed laser is 20μm to 100μm.

11. The method for preparing a solar cell according to claim 9, characterized in that, The scanning speed of the scanning process is 100mm / s to 500mm / s.

12. The method for preparing a solar cell according to claim 9, characterized in that, The bias voltage applied to the preformed gate line is a reverse bias voltage, and the reverse bias voltage is 5V~20V.

13. A solar cell, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 12.

14. A stacked battery, characterized in that, It includes a top cell and a bottom cell, at least one of which is the solar cell of claim 13.

15. A photovoltaic module, characterized in that, It includes: at least one battery string, the battery string including the solar cell of claim 13 or including the tandem battery of claim 14.

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