Glass powder for paste and preparation method thereof, conductive paste and preparation method thereof, battery

Abstract

The present invention discloses a glass frit for a conductive paste for the front surface of a TOPCon solar cell, a preparation method thereof, a conductive paste, a preparation method thereof, and a solar cell. The glass frit comprises a main glass frit A and a secondary glass frit B. The main glass frit A comprises the following components by weight: 30-80 wt% B2O3, 10-50 wt% SiO2, 10-50 wt% SeO2, and 0-20 wt% oxide additives; the secondary glass frit B is Pb-Si-Zn-B glass; and the weight ratio of the main glass frit A to the secondary glass frit B is 4:1-1:4. The glass frit provided by the present invention utilizes a high-borosilicate glass system, which is less corrosive and less susceptible to silicon nitride surface reactions. This system can control corrosion depth and reduce recombination, thereby increasing the open-circuit voltage. This solves the problem of open-circuit voltage drop caused by the use of conductive silver-aluminum paste in the P-type emitter of current TOPCon solar cells.

Description

Technical Field

[0001] The present invention belongs to the technical field of TOPCon solar cell conductive paste, and in particular relates to a glass powder for TOPCon solar cell front conductive paste and a preparation method thereof, a conductive paste and a preparation method thereof, and a battery. Background Art

[0002] As a new photovoltaic cell technology, TOPCon (Tunnel Oxide Passivated Contact) cells have a higher theoretical photoelectric conversion efficiency of 28.7% than the current mainstream P-type PERC cells. Currently, small-scale mass production efficiency can reach 24.5%, indicating significant potential for further growth. TOPCon cell technology is also compatible with current mainstream P-type PERC cell production lines. These lines can be upgraded to TOPCon production lines by adding diffusion, etching, and deposition equipment, significantly reducing the investment cost of the new technology. As a result, TOPCon cell technology is gaining favor with leading battery manufacturers, and is expected to experience rapid growth over the next 1-3 years.

[0003] For the front emitter of N-type TOPCon solar cells, the low doping concentration of the p+ region from boron diffusion results in a very large contact resistance with the silver paste, necessitating the introduction of aluminum to form a silicon-aluminum alloy contact. Therefore, the current TOPCon cell P-type emitter uses a conductive silver-aluminum paste; however, during the sintering process, the aluminum-silicon eutectic formed brings about the side effect of a sharp drop in open-circuit voltage, affecting the battery's electrical performance. Summary of the Invention

[0004] Based on the problems of the prior art, the present invention provides a glass powder for a conductive paste on the front side of a TOPCon solar cell, a preparation method, a conductive paste and a preparation method, and a battery. The glass powder provided by the present invention uses high borosilicate glass as glass. The glass system has weak corrosiveness and is not prone to silicon nitride surface reaction. It can control the corrosion depth and reduce recombination, thereby increasing the open circuit voltage, thereby solving the problem of open circuit voltage drop caused by the use of conductive silver-aluminum paste for the P-type emitter of the current TOPCon battery.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] A glass powder for a TOPCon solar cell front conductive paste, comprising a main glass frit A and a secondary glass frit B, wherein the main glass frit A comprises the following components by weight: 30-80 wt% B2O3, 10-50 wt% SiO2, and 10-50 wt% SeO2;

[0007] The glass frit also includes oxide additives to adjust the glass frit properties and the glass melting temperature and time so that B2O3, SiO2 and SeO2 can form a uniform and stable glass. The content of the oxide additives can be 0-20wt%. The oxide additives include any one or a combination of PbO, Bi2O3, Li2O, Na2O, WO3, ZnO, Al2O3, CaO and BaO.

[0008] The secondary glass frit B is Pb-Si-Zn-B glass, and the components of the secondary glass frit B are PbO 40-80wt%, SiO2 5-20wt%, ZnO 5-20wt%, and B2O3 10-20wt%.

[0009] Preferably, the weight ratio of the main glass frit A to the secondary glass frit B is 4:1-1:4.

[0010] Further preferably, the embodiment of the main glass frit A includes 50-80 wt % B2O3, 10-20 wt % SiO2, 10-20 wt % SeO2, or the main glass frit A includes another embodiment 30-50 wt % B2O3, 20-50 wt % SiO2, 20-50 wt % SeO2.

[0011] Based on the same inventive concept, the present invention also provides a method for preparing glass powder for a TOPCon solar cell front conductive paste, comprising the following steps:

[0012] Preparation of main glass frit A: Analytical pure oxides are mixed according to the formula, and then the mixed materials are melted, and finally cooled and ball-milled to obtain main glass frit A;

[0013] Preparation of secondary glass frit B: Analytical pure oxides are taken according to the formula and stirred and mixed, and then the mixed materials are melted, and finally cooled and ball-milled to obtain secondary glass frit B.

[0014] Preferably, when preparing the main glass material A and the secondary glass material B separately, the glass raw materials can be mixed and placed on a double-roll mill for stirring for 4 hours to fully mix the glass raw materials; then the evenly mixed raw materials are placed in a platinum crucible, and the platinum crucible is placed in a high-temperature muffle furnace and fired at 700-1500°C for 30-120 minutes. The crucible is taken out and poured onto a double-roll cold rolling mill for cold rolling to obtain a glass melt, and then the glass melt is placed on a double-roll mill for ball milling for 6-96 hours to obtain the main glass material A and the secondary glass material B.

[0015] Based on the same inventive concept, the present invention also provides a TOPCon solar cell front conductive paste, including the glass powder used for the above-mentioned TOPCon solar cell P-type emitter conductive paste or the glass powder prepared by the above-mentioned method.

[0016] More preferably, the invention comprises the following components by weight: 80-95 wt % of silver powder, 0.5-10 wt % of glass powder, 0-5 wt % of aluminum powder, and 0.1-5 wt % of inorganic telluride.

[0017] The conductive paste contains aluminum powder in its formula, which can be used to make silver-aluminum paste for the P-type emitter on the front of the TOPCon battery, matching the current conventional +SE process of the TOPCon battery; without adding aluminum powder or adding a very small amount of aluminum powder in the formula, a conductive silver (aluminum) paste for the P-type emitter on the front of the TOPCon battery is made, and matched with the laser induced sintering process.

[0018] Furthermore, the conductive paste includes 1.5-6 wt % of the glass powder and 1-5 wt % of inorganic telluride.

[0019] Preferably, the inorganic telluride includes any one or a combination of lead telluride bismuth (PbBi2Te4), lead telluride (PbTe), bismuth telluride (Bi2Te3), antimony telluride (Sb2Te3), tin telluride (SnTe), zinc telluride (ZnTe), aureolite (AuTe2), aureolite (AuAg3Te2), bismuth telluride lead gold sulfide (AuPb2BiTe2S) or bismuth telluride pyroxene (Bi2Te2S).

[0020] Preferably, the particle size D50 is 1-3 μm and the specific surface area is 0.3-0.7 m 2 / g, tap density 4.0-7.0g / cm 3 of silver powder.

[0021] Preferably, the conductive paste further comprises a resin, a solvent and an additive, wherein the resin accounts for 2-10wt% of the conductive paste, the solvent accounts for 0.5-5wt% of the conductive paste, and the additive accounts for 0-5wt% of the conductive paste;

[0022] The resin comprises one or more of ethyl cellulose, rosin resin, acrylic resin, polyvinyl alcohol carboxybutyral, diethylene glycol monobutyl ether, terpineol, diethylene glycol butyl ether acetate, and alcohol ester twelve;

[0023] The solvent comprises one or more of diethylene glycol monobutyl ether, diethylene glycol butyl ether acetate, alcohol ester dodecahydrate, dimethyl adipate, phenyl oxalate acetate, diethylene glycol dibutyl ether, alcohol ester hexadecane, tripropylene glycol butyl ether, and benzyl benzoate;

[0024] The auxiliary agent includes any one or more of a dispersant, a surfactant or a thixotropic agent.

[0025] Based on the same inventive concept, the present invention also provides a method for preparing a conductive paste for the front side of a TOPCon solar cell. According to the formula ratio, the resin, solvent and additive are heated and stirred to obtain an organic carrier; then the silver powder, glass powder, aluminum powder, inorganic telluride and organic carrier are placed in a reactor with a dispersion disk and stirred for 2 hours, and then placed on a three-roller machine for three-rolling to obtain a conductive paste with a fineness of less than 10μm.

[0026] Based on the same inventive concept, the present invention also provides a TOPCon solar cell, which uses the above-mentioned conductive paste or the conductive paste prepared by the above-mentioned method. When the amount of aluminum powder added in the conductive paste is 0wt% or a very small amount, it can be made into pure silver paste, and a solar cell can be obtained by matching the TOPCon technology with the laser induced sintering process. It can also be made into silver-aluminum paste when containing aluminum powder, and a solar cell can be prepared by the TOPCon technology and SE process.

[0027] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art:

[0028] 1. The glass frit provided by the present invention utilizes borosilicate glass containing 30-80 wt% B2O3 and 10-50 wt% SiO2 as the primary glass, while also adding 10-50 wt% SeO2. The borosilicate glass system exhibits low corrosiveness, resulting in poor glass fluidity during high-temperature sintering of the slurry, making it a glass with excellent high-temperature resistance. The introduction of SeO2 can, to a certain extent, offset the poor high-temperature fluidity of the glass network formed by silica. The Se-O bonding energy is smaller than the Si-O bonding energy, thus enabling the controllable Tg point and fluidity of the borosilicate glass during high-temperature sintering. Borosilicate glass contains no or only a small amount of highly corrosive glass elements, making it less likely to react with the SiNx passivation layer on the surface of crystalline silicon solar cells, thereby corroding them. When used in combination with conventional Pb-Si-Zn-B glass, the glass exhibits controllable corrosion depth, reduces minority carrier recombination in crystalline silicon solar cells, and increases minority carrier lifetime, thereby improving the open-circuit voltage and fill factor of solar cells employing the glass frit.

[0029] 2. In one embodiment, the conductive paste provided by the present invention adds inorganic telluride. Telluride exists in a negative valence state. When the paste is printed on the battery substrate and sintered, it will not affect the formation of aluminum-silicon alloy in the silver-aluminum paste. It can also enhance the silver-dissolving ability of the inorganic melt at high temperature, help to create more contact sites between the electrode and the battery substrate interface, form good contact, and thus improve the contact performance of the conductive paste.

[0030] 3. The conductive paste provided by this invention not only eliminates the side effect of aluminum in silver-aluminum paste, which reduces open-circuit voltage, but also introduces inorganic telluride into the paste, improving its contact performance. This allows its application in conventional TOPCon technology, as well as TOPCon technology combined with laser-induced sintering processes. DETAILED DESCRIPTION

[0031] It should be noted that the current N-type TOPCon solar cell front emitter has a low boron-diffused p+ region doping concentration, resulting in a very large contact resistance with ordinary silver paste. It is necessary to introduce aluminum to form a silicon-aluminum alloy contact. Therefore, the current TOPCon cell P-type emitter uses a conductive silver-aluminum paste; however, during the sintering process, the introduction of aluminum into the silver paste brings about the side effect of increased open-circuit voltage. Many solar cell manufacturers are also seeking to innovate the TOPCon process and perform laser-induced sintering on the cell wafers, but this will result in high contact resistance and low cell efficiency.

[0032] Therefore, the present invention improves the glass powder and adopts high borosilicate glass containing boron oxide, silicon oxide and selenium oxide as the main glass to improve the open circuit voltage of the final battery.

[0033] On the other hand, the tellurium element widely used in PERC cells is generally added to the glass material in the form of tellurium oxide. However, due to its high valence in the glass component, it is easily reduced and reacts with aluminum to oxidize the aluminum, thereby inhibiting the formation of the aluminum-silicon alloy and failing to form good contact. The present invention introduces an inorganic telluride into the conductive paste. Tellurium in the telluride exists in a negative valence state, which is different from the tellurium oxide in the glass component. This not only does not affect the formation of the aluminum-silicon alloy, but also enhances the silver-dissolving ability of the inorganic melt at high temperatures, helping the interface layer to form more contact sites and form good contact. As a result, the slurry of the present invention can be applied not only to conventional TOPCon technology, but also to TOPCon technology matching laser-induced sintering technology.

[0034] The following, combined with specific examples, further describes in detail the glass powder for TOPCon solar cell front conductive paste, its preparation method, the conductive paste, its preparation method, and the solar cell proposed in this invention. The advantages and features of the present invention will become more apparent from the following description. The chemical reagents and silver powder used in the examples herein were purchased commercially.

[0035] Main glass frit A

[0036] Example A1: Analytically pure oxides, 30 parts boron oxide, 50 parts silicon oxide, and 20 parts selenium oxide were mixed in a total weight ratio of 100 parts. The mixture was stirred on a double-roll mill for 4 hours to thoroughly mix the raw materials. The mixed powder was placed in a platinum crucible, calcined in a high-temperature muffle furnace at 1200°C for 80 minutes, and then cold-rolled on a double-roll cold mill to obtain a glass frit. The molten glass was then ball-milled on the double-roll mill for 36 hours to obtain main glass frit A1.

[0037] Example A2: Analytical pure oxide, 80 parts of boron oxide, 10 parts of silicon oxide, and 10 parts of selenium oxide were mixed in a total mass ratio of 100 parts, and main glass material A2 was prepared according to the steps of Example A1.

[0038] Example A3: 100 parts by mass of analytically pure oxide, 50 parts of boron oxide, 20 parts of silicon oxide, 20 parts of selenium oxide, 5 parts of magnesium oxide additive, and 5 parts of lithium oxide additive were mixed, and main glass material A3 was prepared according to the steps of Example A1.

[0039] Secondary glass frit B

[0040] Example B1: Analytical-grade oxides, 60 parts lead oxide, 10 parts boron oxide, 15 parts silicon dioxide, and 15 parts zinc oxide were mixed in a total weight ratio of 100 parts by weight. The mixture was stirred on a double-roll mill for 4 hours to thoroughly mix the raw materials. The mixed powder was placed in a platinum crucible, calcined in a high-temperature muffle furnace at 1000°C for 60 minutes, and then cold-rolled on a double-roll cold mill to obtain a glass frit. The molten glass was then ball-milled on the double-roll mill for 20 hours to obtain secondary glass frit B1.

[0041] The TOPCon front conductive paste is prepared based on the glass material prepared above. The following examples are used to illustrate the current application scenarios of TOPCon conventional + SE technology and TOPCon new technology + laser induced sintering.

[0042] Application scenario 1: Preparation of TOPCon front silver aluminum paste to match the current TOPCon conventional + SE technology.

[0043] Example 1: Based on 100 parts of the total mass ratio, 80 parts of silver powder, 1 part of aluminum powder, 6.4 parts of Example A1, 1.6 parts of Example B1, 5 parts of lead antimonide, 3 parts of resin-ethyl cellulose, and 3 parts of solvent-diethylene glycol butyl ether acetate.

[0044] Example 2: Based on a total mass ratio of 100 parts, 95 parts of silver powder, 0.5 parts of aluminum powder, 1 part of Example A2, 0.5 parts of Example B1, 0.1 parts of bismuth telluride, 1.9 parts of resin - polyvinyl butyral, and 2 parts of solvent - alcohol ester twelve.

[0045] Example 3: Based on a total mass ratio of 100 parts, 85 parts of silver powder, 2 parts of aluminum powder, 1.2 parts of Example A3, 4.8 parts of Example B1, 2 parts of antimony telluride, 2 parts of resin-acrylic resin, 2 parts of solvent-diethylene glycol monobutyl ether, and 1 part of auxiliary agent-dimethyl silicone oil.

[0046] Example 4: Based on a total mass ratio of 100 parts, 90 parts of silver powder, 1 part of aluminum powder, 2 parts of Example A3, 1 part of Example B1, 2 parts of resin-acrylic resin, 3 parts of solvent-diethylene glycol monobutyl ether, and 1 part of auxiliary agent-dimethyl silicone oil.

[0047] Comparative Example 1: Based on 100 parts of the total mass ratio, 90 parts of silver powder, 1 part of aluminum powder, 3 parts of Example B1, 3 parts of resin-ethyl cellulose, and 3 parts of solvent-diethylene glycol butyl ether acetate.

[0048] Comparative Example 2: Based on 100 parts of the total mass ratio, 89 parts of silver powder, 1 part of aluminum powder, 2 parts of Example B1, 3 parts of resin-ethyl cellulose, and 3 parts of solvent-diethylene glycol butyl ether acetate.

[0049] The above examples 1-4 and comparative examples 1-2 were prepared using the same conductive paste preparation method, which is as follows:

[0050] First, the resin, solvent, and additives were placed in a constant temperature oil bath at 90°C and heated and stirred for 4 hours to obtain an organic carrier;

[0051] Then, the organic carrier, silver powder, aluminum powder, main glass material A, secondary glass material B, and inorganic telluride are placed in a reactor with a dispersion plate according to the formula and stirred for 2 hours. After stirring, they are placed on a three-roller machine for three-rolling to obtain a conductive slurry with a fineness of less than 10μm.

[0052] The component ratios of Examples 1-4 and Comparative Examples 1-2 are listed in Table 1 below:

[0053] Table 1

[0054]

[0055] The above conductive paste was used to prepare TOPCon solar cells using the current TOPCon+SE technology. The contact performance, open circuit voltage, and conversion efficiency of the cells were then tested. The performance is shown in Table 2 below:

[0056] Table 2

[0057] <![CDATA[Contact resistance Rc (mΩ.cm -2 )]]> Open circuit voltage (mV) Fill factor (%) conversion efficiency Comparative Example 1 1.80 718.3 84.87 25.15％ Comparative Example 2 1.60 719.8 84.99 25.22％ Example 1 1.35 721.1 85.12 25.42％ Example 2 1.39 721.5 85.10 25.40％ Example 3 1.32 721.9 85.20 25.44％ Example 4 1.70 720.7 85.00 25.30％

[0058] The performance data in Table 2 show that, compared with Comparative Example 1, and compared with Example 1, introducing an inorganic telluride into the conductive paste improves contact performance and reduces contact resistance. Compared with Comparative Example 1, and compared with Comparative Example 2, adding Example A2 containing the main glass frit into the conductive paste increases open-circuit voltage. Overall, Examples 1-4 significantly reduce contact resistance, increase open-circuit voltage, and improve fill factor relative to Comparative Examples 1-2, thereby improving photoelectric conversion efficiency. This demonstrates that the conductive paste provided by the present invention can be successfully applied to TOPCon conventional + SE technology to produce TOPCon solar cells, reducing contact resistance and increasing open-circuit voltage.

[0059] Application scenario 2: Preparation of TOPCon front P-type emitter conductive silver paste, matching TOPCon's new technology laser induced sintering (LECO).

[0060] Example 5: Based on 100 parts by total mass, 80 parts of silver powder, 7 parts of Example A1, 3 parts of Example B1, 4 parts of tin telluride, 2 parts of resin-ethyl cellulose, and 3 parts of solvent-alcohol ester dodecyl acrylate.

[0061] Example 6: Take 95 parts of silver powder, 1 part of Example A2, 0.5 part of Example B1, 0.5 part of zinc antimonide, 1 part of resin-acrylate, and 2 parts of solvent-alcohol ester hexadecane according to a total mass ratio of 100 parts.

[0062] Example 7: Based on a total mass ratio of 100 parts, take 85 parts of silver powder, 0.5 parts of aluminum powder, 1 part of Example A2, 2 parts of Example B1, 3 parts of lead antimonide, 5 parts of bismuth telluride, 2.5 parts of resin - polyvinyl butyral, 3 parts of solvent - diethylene glycol monobutyl ether, and 1 part of auxiliary agent - oleic acid.

[0063] Comparative Example 3: Based on 100 parts of the total mass ratio, 92 parts of silver powder, 2 parts of Example B1, 2 parts of resin-ethyl cellulose, 3 parts of solvent-alcohol ester dodecanol, and 1 part of auxiliary agent-oleic acid were taken.

[0064] The above examples 5-7 were prepared according to the same conductive paste preparation method:

[0065] First, the resin, solvent and additive were placed in a constant temperature oil bath at 90°C and heated and stirred for 4 hours to obtain an organic carrier;

[0066] Then, the organic carrier, silver powder, aluminum powder, main glass material A, secondary glass material B, and inorganic telluride are placed in a reactor with a dispersion plate according to the formula and stirred for 2 hours. After stirring, they are placed on a three-roller machine for three-rolling to obtain a conductive slurry with a fineness of less than 10μm.

[0067] The component ratios of Examples 5-7 and Comparative Example 1 are listed in Table 3 below:

[0068] Table 3

[0069]

[0070] The conductive pastes of Examples 5-7 and Comparative Example 3 were sintered using TOPCon technology to produce TOPCon solar cells. The performance of the produced cells was tested and shown in Table 4 below:

[0071] Table 4

[0072] <![CDATA[Contact resistance Rc (mΩ·cm -2 )]]> Open circuit voltage (mV) Fill factor (%) conversion efficiency Comparative Example 3 1.80 735.2 85.24 25.45％ Example 4 1.62 744.5 85.35 25.62％ Example 5 1.59 746.7 85.32 25.68％ Example 6 1.47 750.2 85.38 25.77％

[0073] From the results of Examples 4-6 and Comparative Example 3, it can be seen that in this scenario, the open circuit voltage and fill factor are also improved, the contact resistance is reduced, and the conversion efficiency is improved.

[0074] The embodiments of the present invention have been described in detail above with reference to the embodiments, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the scope of protection of the present invention.

Claims

1. A glass powder for TOPCon solar cell front conductive paste, characterized in that: The invention comprises a main glass frit A and a secondary glass frit B, wherein the main glass frit A comprises the following components by weight: 30-80 wt% B2O3, 10-50 wt% SiO2, 10-50 wt% SeO2, and 0-20 wt% of an oxide additive, wherein the oxide additive comprises any one or a combination of PbO, Bi2O3, Li2O, Na2O, WO3, ZnO, Al2O3, MgO, CaO, and BaO; The secondary glass frit B is Pb-Si-Zn-B glass; The weight ratio of the main glass material A to the secondary glass material B is 4:1-1:

4.

2. The glass powder for TOPCon solar cell front conductive paste according to claim 1, characterized in that: The main glass frit A comprises 50-80 wt% B2O3, 10-20 wt% SiO2, and 10-20 wt% SeO2 by weight; or The main glass frit A comprises 30-50 wt % B2O3, 20-50 wt % SiO2, and 20-50 wt % SeO2 by weight.

3. A method for preparing glass powder for TOPCon solar cell front conductive paste according to claim 1 or 2, characterized in that: The following steps are involved: Preparation of main glass frit A: Analytical pure oxides are mixed according to the formula, and then the mixed materials are melted, and finally cooled and ball-milled to obtain main glass frit A; Preparation of secondary glass frit B: Analytical pure oxides are taken according to the formula and stirred and mixed, and then the mixed materials are melted, and finally cooled and ball-milled to obtain secondary glass frit B.

4. A TOPCon solar cell front conductive paste, characterized in that: The invention comprises the glass powder for the TOPCon solar cell front conductive paste according to claim 1 or 2, or the glass powder prepared by the method according to claim 3.

5. The TOPCon solar cell front conductive paste according to claim 4, characterized in that: The composition includes the following components by weight: 80-95 wt% of silver powder, 0.5-10 wt% of glass powder, 0-5 wt% of aluminum powder, and 0.1-5 wt% of inorganic telluride.

6. The TOPCon solar cell front conductive paste according to claim 5, characterized in that: The conductive paste includes 1.5-3 wt % of the glass powder and 1-5 wt % of an inorganic telluride.

7. The TOPCon solar cell front conductive paste according to claim 5 or 6, characterized in that: The inorganic telluride includes any one or a combination of tellurium-lead-bismuth ore, lead telluride, bismuth telluride, antimony telluride, tin telluride, zinc telluride, tellurium-gold ore, tellurium-gold-silver ore, tellurium-bismuth-lead-gold ore or tellurium-bismuth-pyroxene ore.

8. The TOPCon solar cell front conductive paste according to claim 4 or 5, characterized in that: It also includes resin, solvent and auxiliary agent, wherein the resin includes one or more of ethyl cellulose, rosin resin, acrylic resin, polyvinyl alcohol carboxybutyral, diethylene glycol monobutyl ether, terpineol, diethylene glycol butyl ether acetate, and alcohol ester dodecahydrate; The solvent comprises one or more of diethylene glycol monobutyl ether, diethylene glycol butyl ether acetate, alcohol ester dodecahydrate, dimethyl adipate, phenyl oxalate acetate, diethylene glycol dibutyl ether, alcohol ester hexadecane, tripropylene glycol butyl ether, and benzyl benzoate; The auxiliary agent includes any one or more of a dispersant, a surfactant or a thixotropic agent.

9. A method for preparing the TOPCon solar cell front conductive paste according to claim 8, characterized in that: The resin, solvent and additive are stirred and mixed to obtain an organic carrier; then silver powder, glass powder, aluminum powder, inorganic telluride and the organic carrier are stirred and mixed, and placed on a three-roller machine for three-rolling to obtain a conductive paste with a fineness of less than 10μm.

10. A TOPCon solar cell, characterized in that: The TOPCon solar cell is prepared by using the conductive paste described in any one of claims 4 to 8 or the conductive paste prepared by the method described in claim 9 through TOPCon technology and SE process; or is prepared by combining TOPCon technology with laser induced sintering process.

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